Thèses sur le sujet « Fillets quality »

This study is aimed at evaluating the safety and quality of pressure treated fish. In order to assess safety of refrigerated fish, the sensitivity of key pathogens like Escherichia coli O157:H7 and Listeria monocytogenes Scott A, which thrive under refrigerated storage conditions, needs to be assessed.
In the first part of the study, the pressure destruction kinetics of E. coli and L. monocytogenes in fish were evaluated at 250 to 400 MPa with a holding time ranging from 0-60 min. A slurry was prepared by blending 20 g filleted fish and 80 ml sterile peptone water (0.1%) in a stomacher. To the slurry, stock cultures of E. coli O157:H7 and L. monocytogenes were added separately and final counts of 107 and 106 CFU/ml were achieved, respectively. Due to the higher overall pressure resistance at 400 MPa, E. coli was selected as the target microorganism in this study for pressure destruction.
The second part of the study focused on storage studies. The first phase of the storage study was a repeat of previous set of experiments with fish slurry inoculated with only E. coli O157:H7 which was more resistant to pressure destruction (challenge study).
The second phase of storage studies evaluated the quality changes associated with pressure treated fish. (Abstract shortened by UMI.)

The spoilage pattern of carp (Cyprinus carpio) fillets was investigated. The studies were aimed at evaluating the potential use of pressure-shift freezing to reduce quality deterioration during frozen storage. The effects of pressure treatment at low temperature on fish carp fillets were evaluated and conditions were chosen to reduce any adverse effect on the quality of fish fillet. Pressure-shift freezing treatment was applied to carp fillets and biochemical properties were evaluated and correlated with objective measurement of texture, drip loss and the size of ice crystals formed. Changes in these properties were monitored during frozen storage for a period of 75 days.
Results indicated that proteolityc changes due to endogenous enzymes in fish muscle play an important role in quality deterioration of carp fillets during ice storage. No changes were observed in Ca2+-ATPase, Mg2+-ATPase or Mg2+-EGTA-ATPase activity of actomyosin from carp fillets during iced storage (p > 0.05). In contrast, Mg2+-Ca2+-ATPase and Ca2+ sensitivity of actomyosin decreased during ice storage of fish fillets. No changes were found in the SH content of actomyosin throughout the ice storage of carp fillets (p > 0.05). The surface hydrophobicity of actomyosin and auto-degradation products increased during the storage period (p < 0.05).
Response surface methodology (RSM) was used to study the effect of high-pressure treatment on some physico-chemical properties (actomyosin extractability, Ca2+-ATPase activity, surface hydrophobicity, TBA value, liquid loss and firmness) of intact fish fillets. Balancing the benefits of low temperature pressurization with the denaturing effects of pressure on fish proteins, it is evident that there is a region in which the responses of the factors (protein extractability, Ca2+-ATPase activity and protein hydrophobicity) to the processing variables (time and pressure) seemed to be adequate to keep protein denaturation to a minimum. This region lies between 140--175 MPa and 16--18 min. However, it was observed that high-pressure treatment induced changes in colour on fish fillets. The L*, a* and b* values increased as pressure and time treatment increased.
The application of pressure-shift freezing or air-blast freezing resulted in decrease in myofibrillar and sarcoplasmic protein extractability, and reduced actomyosin Ca2+-ATPase activity during frozen storage. However, actomyosin Ca2+-ATPase activity in pressure-shift frozen samples remained relatively higher than that of air-blast frozen samples. On the other hand, levels of thiobarbituric acid and free fatty acids were relatively lower in samples frozen by PSF. The freezing procedure did not seem to have a significant effect (p > 0.05) on the texture of carp fillets. The ice crystals found in PSF fish samples were mainly intracellular, smaller and more regular shaped than those found in the ABF samples, which were mainly extracellular. Differential scanning calorimetry showed that PSF treatment appeared to be more effective in preventing protein denaturation in post-rigor fish fillets than in the pre-rigor fish fillets.

Thesis (MScFoodSc)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: Fresh ready-to-cook fish fillets are prone to rapid loss of freshness and other quality attributes, as well as accelerated growth of spoilage micro-organisms under sub-optimal storage conditions. Cape hake (Merluccius capensis) is an important seafood in South Africa; however, rapid loss of quality and eventual spoilage is a problem limiting the economic potential. Thus, the aim of this study was to investigate the effects of active (40% CO2 + 30% O2 + 30% N2) and passive (0.039% CO2 + 20.95% O2 + 78% N2) modified atmosphere packaging (MAP) under different storage temperatures (0°C, 4°C, and 8°C) on the quality attributes of Cape hake (Merluccius capensis) fish fillets. This was achieved by investigating the effects of MAP (with or without absorbent pads) and storage temperature on quality attributes (microbial, physicochemical and sensory), changes in composition and concentration of volatile compounds (VOCs) and shelf life of Cape hake fillets. Modified atmosphere packaging, storage temperature and the use of absorbent pads had a significant (p < 0.05) impacts on physicochemical properties of Cape hake fillets during refrigerated storage. Highest storage temperature (8°C) led to accelerated deterioration of packaged Cape hake fillets. Generally, active MAP better maintained the quality attributes of Cape hake than passive MAP at 0°C and 4°C. Headspace gas composition of O2 and CO2 were significantly influenced by the storage time, temperature, MAP conditions and their interactions (p < 0.05). Irrespective of storage temperature, active-MA packaged fillets had lower pH values in comparison to fillets stored under passive-MAP. Drip loss was higher in active-MA fillets packaged without absorbent pad. Passive-MAP fillets did not show any drip loss. Absorbent pad was used to add value to MAP storage as MAP resulted in drip. The use of absorbent pad combined with low storage temperature maintained the firmness of hake fillets, across all temperatures. The interaction of MAP, absorbent pad and storage temperature had a significant effect on the aerobic mesophillic bacteria counts. Based on the aerobic mesophillic bacteria count fillets stored under active-MAP at 0°C (5.2 log cfu/g) was limited to day 12, while the fillet stored under passive-MAP at 0°C (log cfu/g) was limited to greater than day 3. Overall sensory acceptability of fillets decreased with increase in storage temperature across all treatments. Additionally, MAP had a significant (p < 0.05) impact on sensory attributes such as appearance and odour acceptability, with active-MA packaged fillets stored at 0°C having highest overall acceptability. A total of 16 volatiles were identified in Cape hake fillets, including 4 primary VOCs and 12 secondary VOCs. The VOCs associated with spoilage include tri-methylamine (TMA) (ammonia like), esters (sickeningly sweet) and sulphur group (putrid). MAP had a significant (p< 0.05) influence on volatile composition and concentration. Active-MA packaged fillets performed better during storage and had lower TMA value of 0.85% on day 12 in comparison with 7.22% under passive-MAP on day 6 at 0°C. The results obtained demonstrated that changes in volatile compounds were significantly (p< 0.05) influenced by storage duration, temperature and MAP. The development of high levels of VOCs and off-odour corresponded with high aerobic mesophillic bacteria count (≥ 5.5 log cfu/g). Based on these developments the storage life of Cape hake fillets packaged under active-MAP with absorbent pad and stored at 0°C was limited to 12 d, while the passive-MAP (control) fillets stored at 0°C was limited to 3 d. The use of active-MAP, in combination with absorbent pads and 0°C storage in addition to good hygienic practices, was effective in maintaining the postharvest quality of Cape hake fish fillets and led to higher shelf life.
AFRIKAANSE OPSOMMING: Vars, gereed-vir-kook vis filette is geneig om gou hulle varsheid en ander gehalte kenmerke te verloor en die vervoegde groei van mikro-organismes wat bederf tydens stoor veroorsaak, vind plaas. Kaapse stokvis (Merluccius capensis) is in Suid-Afrika ‘n gewilde seekos maar die ekonomiese potensiaal daarvan word deur die feit dat dit so gou in gehalte afneem en bederf, beperk. Dus word daar met hierdie studie gepoog om die effek van aktiewe (40% CO2 + 30% O2 + 30% N2) en passiewe (0.039% CO2 + 20.95% O2 + 78% N2) aangepasde verpakking (MAP) onder verskillende stoortemperature (0°C, 4°C, en 8°C) op die gehalte kenmerke van Kaapse stokvis (Merluccius capensis) filette te ondersoek. Dit is gedoen deur om die effek van MAP (met of sonder kussinkies) en stoortemperatuur op die gehalte kenmerke (mikrobies, fisiochemies en sensories) asook veranderinge in komposisie en konsentrasie van vlugtige samestellings (VOCs) en die raklewe van Kaapse stokvis filette te ondersoek. Aangepasde atmosfeer verpakking, stoortemperatuur en die gebruik van absorberende kussinkies het ‘n groot impak (p < 0.05) op die fisiochemiese kenmerke van Kaapse stokvis tydens stoor in yskaste gehad. Hoë stoortemperature (8°C) het aanleiding gegee tot die vinnige bederf van verpakte Kaapse stokvis filette. Oor die algemeen het aktiewe MAP die gehalte van die Kaapse stokvis filette teen 0°C and 4°C beter bewaar. Die komposisie van O2 en CO2 is heelwat deur stoortyd, temperatuur, MA toestande en die interaksies tussen bogenoemde, beïnvloed (p< 0.05). By alle temperature het aktiewe MA verpakte filette laer pH waardes getoon in vergeleke met filette wat in onder passiewe MA verpak is. Die drupverlies was hoër in aktiewe MA filette verpak sonder absorberende kussinkies. Passiewe MAP filette het nie enige drupverlies getoon nie. Absorberende kussinkies is gebruik om waarde by te voeg tot MAP stoor aaangesien MAP gelei het tot drup. By alle temperature het die gebruik van absorberende kussinkies tesame met lae stoortemperature bygedra tot die behoud van fermheid. Die interaksie van MAP, absorberende kussinkies, en stoortemperatuur het ‘n groot effek gehad op die aerobiese mesofiliese bakterië telling. Weens die aerobiese mesofiliese bakterië telling is stoor van filette onder aktiewe MAP teen 0°C (5.2 log cfu/g) beperk tot dag 12, terwyl filette gestoor onder passiewe MAP teen 0°C ( log cfu/g) beperk is tot dag 3. Oor die algemeen het die sensoriese aanneemlikheid van filette sonder inasgneming van die behandeling, verklein met ‘n toename in stoortemperature. MAP het ook ‘n groot impak op die sensoriese kenmerke soos voorkoms, reuk, en aktiewe MA verpakte fillets gestoor teen 0°C is oor die algemeen die aanneemlikste. ‘n Totaal van 16 vlugtige substanse is in Kaapse stokvis identifiseer. Dit het vier primêre VOCs en 12 sekondêre VOCs ingesluit. Die VOCs wat met bederf assosieer word, sluit tri-metilamien (TMA) (soos ammoniak), esters (soet) en die swael groep (smetterig) in. MAP het ‘n groot (p < 0.05) invloed op die vlugtige komposisie en konsentrasie. Aktiewe MA verpakte filette het beter tydens stoor presteer en het ‘n laer TMA waarde van 0.85% op dag 12 gehad, in vergelyking met 7.22 % onder passiewe MAP op dag 6 teen 0°C. Die resultate toon dat veranderinge in vlugtige samestellings grootliks beïnvloed word (p < 0.05) deur stoortyd, temperature en MAP. Die ontwikkeling van hoë vlakke van VOCs, slegte reuke en verlies aan varsheid gaan tesame met hoë aerobiese mesofiliese bakterië telling (≥ 5.5 log cfu/g). Gegrond op hierdie tellings is die stoorleeftyd van Kaapse stokvis filette beperk tot dag 12, terwyl passiewe MAP (die kontrole) filette gestoor teen 0°C, beperk is tot dag 3. Om op te som, die gebruik van aktiewe MAP tesame met absorberende kussinkies en 0°C stoor asook goeie higiëniese praktyk, kon die na-oes gehalte van Kaapse stokvis filette behou en het gelei tot ‘n langer rakleeftyd.

In the present study the effects of characteristic freezing times and storage time at -22°C on the quality of the adductor muscle of post-rigor scallops (Pecten maximus)and gilthead seabream fillets (Sparusa urata) were studied in regard to the integrity of muscle structure, myofibrillar protein denaturation and aggregation, lipid degradation, texture and sensory changes. This information would be useful for achieving optimal conditions for freezing these species and assessing their quality during frozen storage for commercial purposes. Scallop muscles and gilthead seabream fillets were frozen individually with characteristic freezing times that can be met in commercial practice of freezing seafoods. After freezing, the samples were thawed and their quality was evaluated. Fresh samples were analyzed as controls. Intermediate characteristic freezing times (i. e. 89 and 49 minutes for scallop muscles and 74 minutes for gilthead seabream fillets) caused more damage to cell structure of both species than the shorter and longer characteristic freezing times tested. Short characteristic freezing times (i. e. 19 minutes for scallop muscles, and 2 and 18 minutes for gilthead seabream fillets) reduced the thawing losses of both species compared to the longer characteristic freezing times (. e. 235 to 1000 minutes for scallop muscles, and 640 minutes for gilthead seabream fillets) tested. Freezing at short characteristic freezing times produced raw fillets similar in texture to the fresh fillets. Therefore, short characteristic freezing times (equal to or less than 19 minutes) are beneficial for freezing both species. Scallop muscles and gilthead seabream fillets were kept frozen for up to 301 and 340 days, respectively. Sampling was carried out at regular intervals on fresh and stored frozen samples. Storage time affected the integrity of infra-cellular organelles, reduced the water holding capacity, caused structural changes to myofibrillar proteins and affected the sensory attributes of both species. Frozen scallop muscles were in acceptable eating condition after a storage period of ten months, with most of the changes in bio-chemical and physical properties being pronounced after three months of storage. Based on the changes in taste scores versus storage time, it was assessed that the practical storage life of frozen gilthead seabream fillets was circa 5 to 6 months Cat+-ATPase activities for scallop muscles and a linear model that combines free fatty acids, peroxide values and protein content in centrifugal tissue fluids for gilthead seabream fillets, may be reliable methods for industry to use for assessing their quality during long term storage at -22°C.

The application of high pressure (HP) processing on trout and shrimps was investigated in order to study its effect on their quality attributes. Five levels of pressure, holding time and temperature were selected using a central composite rotatable design (CCRD), the central point being. 200 MPa, 30 min and 10°C. This design was used in order to permit the measurement and modeling of changes in various quality parameters as a result of changes in the process variables. The color parameters (L*, a*, and b* values), physical attributes (drip-loss, protein leaching and water holding capacity) and texture parameters (firmness and springiness) in each case were evaluated, and modeled as second order polynomial equations.
Artificial Neural Network modeling was employed to investigate its ability in predicting the quality changes in both pressure-treated trout fillets and shrimp samples, and its performance was with statistical models.
High pressure (HP) kinetics of the microbial destruction in both trout and shrimp was also studied. (Abstract shortened by UMI.)

In questo lavoro di tesi è stato dimostrato come la Risonanza Magnetica Nucleare (NMR) sia una tecnica in grado di valutare gli effetti della dieta sul profilo molecolare di campioni di salmoni freschi e di campioni trattati con una particolare tecnica di affumicatura denominata “crio-affumicatura”, che prevede un’affumicatura a 5 °C per un tempo di 3 ore mediante un flusso continuo di azoto. Nello specifico, i campioni di salmone sono stati allevati utilizzando due formulazioni differenti di mangimi, una commerciale ed una innovativa. L’analisi NMR accoppiata con un approccio di tipo metabolomico consente la determinazione simultanea di un’ampia classe di metaboliti che costituiscono il campione attraverso la generazione di spettri che contengono moltissime informazioni. Queste informazioni possono essere utili al fine di capire come l’alimentazione possa influenzare tutto il pattern metabolico e come di conseguenza anche i parametri relativi alla freschezza del pesce come il k-index, il rapporto TMA/TMAO e l’insieme degli aminoacidi ne risentano. I dati spettroscopici ottenuti sono stati interpretati attraverso analisi statistica sia univariata (ANOVA e TUKEY Test), sia multivariata, nello specifico in questo ultimo caso l’analisi delle componenti principali o PCA, per individuare eventuali differenze significative tra i due gruppi a seguito della diversa tipologia di alimentazione. Dal presente lavoro di tesi è stato possibile concludere che i campioni vengono distribuiti e classificati in funzione della dieta. Inoltre, è stato possibile individuare i metaboliti che maggiormente determinano questa separazione.

Qualitative and quantitative levels of human pathogens (Listeria monocytogenes, Clostridium botulinum, Salmonella species, Vibrio cholerae, Yersinia enterocolitica and Y. pseudotuberculosis) and general microbial quality of whole aquacultured rainbow trout (Oncorhynchus mykiss) were in compare differing aquacultural systems and growing seasons. Listeria levels and general microbial quality were determined on fillets from three facilities and compared to whole fish. Secondly, in each facility and season, levels of select minerals and heavy metals in edible tissue were determined. Aerobic plate counts for whole fish and fillets ranged from 3-6 logs. Coliform counts were high in many cases, but fecal coliform, and E. coli were comparatively lower. Both whole fish and fillets showed similar Listeria incidence (25-90%) and respective levels of 1.12-21 and 0.36-4.83 MPN/g. Presumptive C. botulinum incidence was 45-95% with levels of 0.46-2.33 MPN/g. Coliform, fecal coliforms, and E. coli counts and Listeria and C. botulinum incidence and counts were significant in plant/year interaction (p<0.05). A significant increase from whole fish to fillets in mesophilic APC, coliforms, and Listeria counts (p<0.05) was observed. No Salmonella, Vibrio cholerae, or Yersinia were isolated from any sample. Levels of Na, Zn, S, Ca, Mg, Mn, and Fe were generally within normal ranges. The heavy metals- As, Hg, Ni, Co, Cr, Mo, Pb, and Cd when detected, were below 0.5 ppm, with the exception of Cd in one sample (60.49 ppm). The presence of both C. botulinum and Listeria would be of concern to processors, although no heavy metals were at levels to cause concern.
Master of Science

Tradicionalment en el camp de la discapacitat s’estudiava l’impacte negatiu que tenia en les mares i els pares el fet de tenir un fill o filla amb discapacitat intel·lectual (DI). S’avaluaven els nivells d’estrès, d’ansietat i depressió que presentaven aquestes famílies i quines variables hi podien influir. Progressivament, van anar apareixent treballs que analitzaven les percepcions positives de les famílies respecte les contribucions del seu fill o filla amb DI a la família. Paral·lelament, l’enfocament teòric sistèmic i ecològic de la família amb fills/es amb discapacitat anava agafant més rellevància entre la comunitat científica i els/les professionals d’aquest àmbit; donant lloc a l’estudi i conceptualització de la qualitat de vida familiar (QdVF) de les famílies amb persones amb DI. Recentment es troben treballs que analitzen diferents factors, entre ells les variables sociodemogràfiques, que poden estar relacionats amb la QdVF. No obstant, no es troben estudis que avaluïn les relacions entre les percepcions positives de les famílies amb un fill o filla amb DI i la QdVF en població espanyola. L’objectiu principal d’aquesta tesi doctoral consistia en avaluar la presència de percepcions positives en les famílies amb fills o filles amb DI al llarg del seu cicle vital en població espanyola, així com l’anàlisi de les relacions entre aquestes percepcions positives i la QdVF. Per tal de recollir dades sobre els percepcions positives, es va realitzar l’adaptació i validació de l’instrument de mesura Kansas Inventory Parental Perceptions (KIPP) en població espanyola. Aquesta tesi està configurada per quatre articles. La mostra es va composar de 861 famílies d’arreu del territori espanyol amb una persona a la família amb DI d’entre 1 i 70 anys d’edat. Els pares, les mares o d’altres familiars van respondre els instruments de mesura Escala de Contribuciones Positivas (PCS) de l’Inventario de Percepciones Parentales i Escala de Calidad de Vida Familiar (CdVF-E 0-18 i CdVF-E >18 años). Es van aplicar anàlisis bivariants per estudiar l'efecte de les variables demogràfiques i les puntuacions de les percepcions positives en les puntuacions de QdVF. Es van realitzar anàlisis de regressió per predir els nivells de QdVF. Els resultats indicaven que les famílies amb fills o filles amb DI de qualsevol edat en la població espanyola mostraven percepcions positives. A més, la presència de nivells més elevats de percepcions positives en les famílies amb persones amb DI estava significativament relacionat amb nivells més elevats de QdVF. L’anàlisi predictiu de la QdVF mostrava que tant en famílies amb infants o adolescents amb DI com en famílies amb persones adultes amb DI s’obtenia un efecte significatiu entre les percepcions positives i la QdVF, fins i tot quan l’efecte de les variables demogràfiques s’eliminava del model. Aquests resultats evidenciaven la importància del paper de les percepcions positives en les famílies amb una persona amb DI, a l’hora de promoure la seva QdVF. En les implicacions pràctiques es discutia la necessitat de potenciar les percepcions positives per part dels i les professionals, per empoderar a les famílies i treballar des d’un enfocament centrat en la família.
In the field of disability studies, authors have traditionally studied the negative impact on parents of having a child with intellectual disabilities (ID). Gradually, studies have begun to appear that analyze families’ positive perceptions regarding the contributions of their child, adolescent or adult member with ID to the family. In parallel, the use of a systematic theoretical and ecological approach in families with disabled children has taken on increasing relevance in the scientific community and among professionals in this field, leading to the study and conceptualization of family quality of life (FQoL) in families with people with ID. Recent studies have analyzed different factors which may be related to FQoL. However, there are no studies that evaluate the relationship between families’ positive perceptions of their family member with ID and FQoL in the Spanish population. The main objective of this PhD thesis was to evaluate the presence of positive perceptions in families with a family member with ID throughout their life cycle in the Spanish population, as well as to analyze the relationships between these positive perceptions and FQoL. The thesis is formed by four articles. The sample of participants comprised 861 families from all over Spain with a person in the family with ID between 1 and 70 years old. Parents or other relatives completed the Positive Contributions Scale (PCS) and the Spanish version of the Family Quality of Life Scales (FQoL <18 and >18 years). Bivariate analyses were applied to study the effect of demographic variables and positive perceptions scores on FQoL scores. Regression analyses were performed to predict FQoL levels. The results suggested that the presence of these positive perceptions in families with people with ID was significantly associated with increased FQoL scores. The predictive analysis of FQoL showed that in both groups of families with a member with ID younger or older than 18 years of age, there was a significant effect from positive perceptions on the reported levels of FQoL. The present results provided further evidence of the role of positive perceptions in families with a person who have ID, in order to promote their FQoL. Among the practical implications of these results we stressed that professionals should promote positive perceptions in order to empower families and they should apply a family-centered approach.

The aims of this research project were to identify and classify the binder-filler interfaces formed in carbon electrodes and to determine the effects of the interfacial quality on important electrode properties. The effects of raw materials and some fabrication process variables on interfacial characteristics and quality of laboratory produced test electrodes were also studied, and the development of binder-filler interfaces during the carbonisation process followed. Electrode quality was assessed by measurement of density, electrical resistivity and tensile strength. Pore structural data were also obtained by using a computerised image analysis system allied to an optical microscope. Interface quality data were obtained by examining etched surfaces in a scanning electron microscope and classifying the binder-filler interface observed into one of five categories. The category depending on the extent of contact between the binder and filler. Accordingly, test electrodes were produced from combinations of four filler carbons, comprising three grades of calcined petroleum coke and an electro-calcined anthracite, and four coal-tar binder pitches which varied in the type and quantity of insoluble matter content. Examination of these test electrodes showed that the nature of the filler carbon used had a dominant influence on the quality of the interface formed, as assessed by this technique. A combination of one filler carbon and one binder pitch was used to study the effects of some fabrication process variables. These were pitch content and, mixing time and temperature. Of these process variables, pitch content and mixing temperature were found to have the major effects on the binder-filler interface and electrode quality. Investigation of the development of the binder-filler interfaces during the carbonisation process showed three distinct zones of interface development and transformation. These zones were associated with three temperature dependent mechanisms; thermal stress relaxation between 200-350 degrees C, volatile gas evolution from coal-tar pitch decompositionb etween3 50-600 degrees C and stresses induced by thermal contraction of the binder phase between 600-1000 degrees C.

The effects of pre-freezing treatments such as time-temperature abuse, use of ice, freeze–thaw cycles, use of polyphosphate and post freezing treatments such as glazing and packaging were assessed on the microbiological and physiochemical properties of barramundi (Lates calcarifer) fillets. The results indicated that the use of sodium tripolyphosphate, constant temperature and use of ice in the form of slurry can improve the shelf life of barramundi fillets.

Hybrid striped bass (Sunshine Bass) were raised in an indoor recirculating aquaculture system incorporating concrete culture tanks, sump tanks, rotating biological contactors and liquid oxygen injection and underground U-tubes for aeration. Fish were anesthetized by two methods after harvest to reduce metabolic activity. Hybrid striped bass were either held in cooled water or water with elevated CO₂ levels prior to sacrificing and filleting. Control fish were filleted immediately or three hours after harvest. The objectives of this study were to determine the effects of these treatments on fillet quality and to develop indicators of quality and shelf life. All fillets were stored at 1-4°C and tested over a 14-day period. Analyses included aerobic plate count, pH determination, texture measurements (Instron), color measurements (L* a* b* scale) and sensory panel evaluations of cooked portions for appearance, taste, odor and texture. Fillets of the cooled water treatment group had the highest pH and were significantly less firm (Instron). Log phase growth and the time for spoilage levels of microorganisms to grow were delayed one day in the CO₂ fillets. In addition, the CO₂ treated fillets were generally rated higher in sensory attributes than the other fillets, especially late in the test period.
Master of Science

Tilapia are freshwater fish that have become important in aquaculture and as a stable global source of seafood due to their ability to thrive in different environments. However, tilapia are sometimes considered nutritionally undesirable due to their high n-6 to n-3 fatty acid ratios. A market study was conducted first to determine fatty acid compositions in tilapia fillets in different US markets. Then a research was conducted to enhance nutritional value of tilapia by improving the n-3 and oleic acid contents in fish fillets without compromising fish growth or feed conversion ratios. Feeds were formulated with combinations of high and low n-6, n-3, and oleic acid levels using soybean oil, fish oil, algae oil, and high-oleic sunflower oil. Then 12 diets, including a commercial diet, were assigned to 24 tanks, each with 25 tilapia per tank. A Recirculating Aquaculture System (RAS) was used to grow the fish for 8 weeks. Fatty acid compositions of tilapia fillets were determined and samples were vacuum packed and stored at -10oC and -20oC to test oxidative degradation and fatty acid compositional changes. The market survey data showed that there were significant differences in fatty acid composition, lipid content, and n-6:n-3 fatty acid ratios depending on the country of origin. Samples from USA had ideal n-6:n-3 ratios (1.3 ±0.85) while samples from Southeast Asia had higher n-6:n-3 fatty acids ratio (6.6 ±0.54). Algae oil incorporation significantly increased DHA level while fish oil incorporation significantly increased both EPA and DPA. High-oleic sunflower oil based diets improved oleic acid levels and reduced linoleic acid compared to the soybean oil based diets. Sensory evaluation indicated that lipid source did not significantly impact preference or overall fillet quality, including texture. Interestingly, a survey showed people were interested in value-added tilapia, and would pay up to 30% more for nutritionally enhanced fish compared to the $5.00/lb fresh fillet price currently available in supermarkets. There was no observable oxidation during long term frozen storage. The oxidation study proved that value-addition would not be compromised during the long term storage conditions, even under temperature abuse. It is possible to improve tilapia nutritional quality through diet to provide consumers with value-added products that maintain quality during frozen storage.
Ph. D.

Welding is a key process for heavy steel structures, but it is also a weak link in the structure since fatigue fractures in welds are a common cause of failure. This thesis proposes several changes in order to improve the fatigue properties in acost effective way, enabling reduced weight and reduced cost of welded structures. The main idea is to adapt the weld requirements and welding procedures to the load conditions of the weld. This approach ensures that the main focus in the welding process is the critical characteristics of the welds fatigue life properties. The fatigue life critical properties are most often related to the geometrical factors of the weld such as the radius at the weld toe or the penetration in the root. The thesis describes a holistic view of the subject and covers fatigue, weld quality, weld requirements and welding procedures. It becomes evident that the traditional way of working without a direct connection to fatigue is not the best. With an adaptation to the load conditions and fatigue, it is possible to enhance the fatigue life and reduce the welding cost. The main challenge is to connect the welding process, weld requirements and fatigue life properties. It is needed for an optimised welding process of heavy structures subjected to fatigue and toget a predictable fatigue life. Welds optimised for enhanced fatigue life properties are not necessary accepted according to the requirements in a current standard. Several welding procedures are proposed for improving the fatigue life properties of the weld, which indicate a high potential for enhanced fatigue lifeof fillet welds. The idea is to replace the "standard" fillet weld with three different weld types: (i) Welds with deep penetration, (ii) Welds with large weld toe radius and (iii) Welds produced with low cost. Together with customised requirements and reduced over-welding there is a vast potential for reduced weight, reduced cost and increased productivity.The main contribution of this thesis work is the cross-functional studies including design, analysis, production and quality control. This gives a framework for improvements supporting reduced cost and reduced weight of VIII welded structures without reducing the fatigue strength. Many shortcomings have been highlighted to change the welding from a state where welds are done in a way as they "always" have, by tradition, to a more contemporary situation where weld requirements and welding procedures are actively chosen to match the load conditions of the weld. This result in requirements and welding procedures which actually are connected to the fatigue properties as defined by the loading conditions, and where auditors with high probability can say that an accepted weld actually is better than a rejected weld.

La présente recherche s’intéresse aux élèves du primaire (6-9ans) qui ont des problèmes de comportement, en particulier les filles, et concerne la qualité de leur adaptation lors du passage à l’adolescence. À risque élevé de persistance lorsqu’ils débutent à l’enfance, les problèmes de comportement sévères sont reliés au développement de conséquences négatives futures. Par contre, dans certains cas, les jeunes ne persisteront pas dans une trajectoire de trouble de comportement à l’adolescence. Il reste tout de même à savoir si leur niveau d’adaptation est acceptable. L’étude vise d’abord à identifier, chez des enfants (N=435) en troubles de comportement précoces, des sous-groupes latents selon la qualité de leur adaptation, puis à décrire et comparer les facteurs individuels et environnementaux qui sont associés à la qualité de leur adaptation au début de l’adolescence en vérifiant l’effet modérateur du sexe. Les résultats montrent un modèle à trois classes ; un sous-groupe d’enfants présentant une adaptation positive à l’adolescence, un sous-groupe ayant une adaptation plus négative et un troisième sous-groupe où les enfants, surtout des filles, présentent une adaptation encore plus difficile. De plus, seuls trois facteurs individuels (opposition, agressivité indirecte et performance scolaire) et trois facteurs environnementaux (consommation des parents, discipline coercitive et fréquentation de pairs déviants) prédisent l’appartenance à un sous-groupe. Les résultats soutiennent l’importance d’une meilleure connaissance des facteurs prédicteurs de la qualité d’adaptation afin d’intervenir dès l’apparition des premiers indices du trouble de comportement en ciblant particulièrement les filles.

Cette étude se penche sur les difficultés relationnelles vécues par les patientes référées au Centre de traitement le Faubourg Saint-Jean (CTFSJ) à la suite de leur passage à l’urgence dans un contexte de crise. La recherche porte plus précisément sur les associations entre les expériences d’abus sexuels en enfance (ASE) et les représentations d’attachement, la satisfaction conjugale ainsi que l’instabilité conjugale à l’âge adulte. L’échantillon d’intérêt se compose de 81 femmes recrutées au CTFSJ. Des comparaisons sont effectuées avec un échantillon de comparaison de 202 patientes recrutées au Service de consultation de l’École de psychologie de l’Université Laval ainsi qu’avec un échantillon de convenance de 1467 femmes recrutées au sein de la population générale et universitaire. La prévalence de l’ASE mesurée au sein de l’échantillon du CTFSJ s’élève à plus d’une personne sur deux, ce taux étant plus de deux fois supérieur à ce qui est retrouvé dans l’échantillon de convenance. Les résultats confirment la sévérité de la symptomatologie des participantes du CTFSJ, où près de la totalité de l’échantillon fait notamment état d’un attachement insécurisant. Aucune différence n’est retrouvée entre les participantes abusées sexuellement et celles n’ayant pas subi ce type d’abus en ce qui a trait aux deux dimensions de l’attachement, de la satisfaction et de l’instabilité conjugale, ni en fonction de la sévérité de l’ASE. Ces résultats devraient être répliqués au sein d’un échantillon plus large de patientes du CTFSJ et en incluant des mesures permettant d’investiguer la présence de multiples traumas développementaux.

Doctor of Philosophy
Department of Physics
Kristan L. Corwin
The focus of this research is improving the pulse output energy of a mid-IR pulsed acetylene-filled Hollow-core Optical Fiber Gas LASer (HOFGLAS) system. Pump pulses and acetylene molecules interact with each other inside hollow-core photonic crystal fiber that effectively confines light and allows for strong gain. This results in lasing at 3.11 μm and 3.17 μm lines based on population inversion of acetylene molecules, which are optically pumped at rotational-vibrational overtones near 1.5 μm using 1 ns pulse duration from an optical parametric amplifier (OPA). This acetylene laser operates with no cavity mirrors because of a high gain in a single pass configuration. There are few laser sources in the mid-IR region while there are many applications for having a laser source in this range such as remote sensing, hazardous chemical detection, and breath analysis. This adds to the importance of the acetylene-filled HOFGLAS system. Some of the applications like remote sensing require high power. So, we moved toward power scaling this laser system by optimizing the laser operation through maximizing the OPA alignment to improve its modal content using longer length of fiber to increase the interaction length and improving the beam quality of the mid-IR emissions. The highest pulse energy ever obtained in the 3 µm mid-IR region from the acetylene-filled HOFGLAS after applying the improvements is reported here (1.4 μJ). Higher mid-IR pulse energies can be achieved by improving the pulse energy achievable from the OPA pump source and working with longer pulse duration to decrease the bandwidth of the OPA. This operation demonstrates many novel properties of acetylene-filled pulsed mid-IR hollow-core fiber lasers. The excellent spatial beam quality at highest power and phenomenological scaling of saturation power and efficiency with pressure that we observe point to the promise of power scaling and motivate further development of numerical models of the laser for deeper insight into these effects. M² measurement method was used to examine spatial beam quality and it was found to be fiber-dependent. For the improved setup, M² was investigated at several input pump powers in addition to the reproducibility checks. M² of 1.14 at the maximum output power motivates for beam combining to scale to higher power. The independence of efficiency on pressure is an evidence for reaching higher mid-IR power at a pressure where saturation behavior does not exist. achieving the highest mid-IR power to date, 1.4 μJ, encourages for building higher power OPA to produce high power mid-IR emissions. Taken as a whole, this laser exhibits novel behavior that motivates both numerical/theoretical investigation and further efforts to scale to higher powers.

A balanced diet and an appropriate feeding are the two most important requirements of aquaculture. Research on feed, quality control and biological evaluation are important to formulate correct diets because without correct and suitable feeding, fish are unable to stay healthy and productive. Furthermore, quality and composition of feeds deeply affect the nutritional and organoleptic characteristics of the final product. In the last years, fish meal has been gradually and partially substituted by plant-based products, because of their improved sustainability and lower costs. Soybean meal is the principal vegetable protein source, due to its high protein content, good amino acid profile, high digestibility, low cost, consistency and availability. Soybean meal contains isoflavones which are polyphenolic compounds (genistein, daidzein, glycitein) that, as phytoestrogens, may act as estrogen receptor agonists or antagonists causing biological activity on fish in addiction to possible changes on the fillet quality. The potential effects of isoflavones may affect the soybean meal utilization as an alternative protein source in aquaculture feed. In the meantime, it is important, for consumer safety, to evaluate the potential amount of the isoflavones in edible tissue and their antioxidant effect that could enhance the product shelf life. Our objective was to examine, on the one hand, the effect of dietary isoflavones on growth, reproduction and health in rainbow trout (Oncorhynchus mykiss), and on the other hand, on the quality of fish food. Rainbow trout were fed three experimental diets containing different concentrations of isoflavones (0, 500, 1500 ppm) for 70 days. Growth, estrogenic activity expressed by vitellogenin (VTG) protein levels in plasma and liver, plasma 17β-estradiol (E2) levels, gonadal development, state of stress and histological changes in various tissues were evaluated in a subsample of the animals at the end of feeding trial. Complementary analyses on growth performance, proximate composition, lipid oxidation and isoflavone deposition were carried out on the remaining part of the animals for each treatment, after being stored at 4 °C for 1 and 7 days. Neither growth performance nor the relative mRNA levels of the liver Insulin Growh Factor I (Igf-I) were influenced by different levels of dietary isoflavones. Plasma and liver VTG protein levels and plasma E2 were unaffected by the treatments and the correlation between E2 plasma levels and VTG densitometry values was significant (p < 0.05). The fish gonadosomatic index (GSI) did not significantly differ among the three experimental groups but correlated with plasma VTG densitometry values (p < 0.05). Plasma, muscle and fin cortisol concentrations fell within the normal welfare range and were not correlated to isoflavone levels. Histologically, the distal intestine showed a normal morphology with well-differentiated enterocytes, as well as the liver showed normal hepatocytes. A supranuclear accumulation of lipid droplets in enterocytes and some lipid droplets in hepatocytes were observed in all the tested groups, suggesting an impact of basal dietary lipid on transport/metabolism of fat in the fish. Inclusion and different levels of isoflavones in diets did not affect the performance of trout used for final product analysis either. Indeed, trout showed similar body weight at caught, 337 g on average, and an average gutted body weight of 299 g. Biometric indexes, skin and fillet colour, rheological characteristics, proximate composition and fatty acids profile of fillet were not affected by the different dietary treatments. Otherwise, time of storage reduced fillet yield (56.4 vs. 53.6%; p < 0.01), and skin lightness (59.2 vs. 51.5; p < 0.001); red index moved to more negative values (p < 0.001) and yellow index decreased (6.99 vs. 5.07; p < 0.001). Fillet pH (6.22 vs. 6.34; p < 0.001) and lightness increased (38 vs. 43.6; p < 0.001) while yellow index (6.20 vs. 4.52; p < 0.001) and shear force decreased (0.94 vs. 0.80 g kg-1; p < 0.001). According to the time of storage, trout fillet showed an increase of water, a loss of crude protein and an increase of total volatile basic nitrogen content (19.3 vs. 21.2 mg 100 g-1; p < 0.001). As a result of PUFAs omega-6 decrease (13.1% vs. 12.7%; p < 0.05), omega-3/omega-6 ratio increased (1.05 vs. 1.20; p < 0.05) during storage. The results evidenced an accumulation of isoflavones on trout fillets, even if isoflavone concentration in fillets was not significantly influenced by the content of dietary isoflavones in both storage times. Lipid peroxidation expressed as thiobarbituric acid reactive substances (TBARS) levels in fillet on day 1 of refrigeration was significantly higher than that at day 7 (p < 0.05) but no difference resulted among groups fed different isoflavone levels, evidencing no effect of feed soy isoflavones on fillet lipid oxidation. Overall, these results suggest that the isoflavone tested doses do not compromise rainbow trout reproduction, growth and health; although a moderate transfer of isoflavones from diet to fillet was observed, quality, technological and nutritional characteristics and lipid oxidation, were not affected by dietary treatment. Our data demonstrate that, with regard to isoflavone contents and their potential effects, soybean meal can replace fish meal in rainbow trout diets at a high level with no negative effects on fish performance and final product quality.
Una dieta bilanciata e un’appropriata alimentazione sono le due maggiori richieste da parte dell’acquacoltura. Gli studi scientifici sui mangimi, il controllo qualità e la valutazione dell’aspetto biologico sono importanti per formulare una corretta e idonea dieta per le specie ittiche. Senza un’adeguata alimentazione, il pesce non può crescere nei tempi stabiliti e mantenersi in salute, oltre al fatto che la qualità e la composizione dei mangimi influenzano profondamente le caratteristiche nutrizionali e organolettiche del prodotto finale. Negli ultimi anni, la farina di pesce è stata sostituita gradualmente e parzialmente dai prodotti derivati dalle piante, per il loro basso costo e la loro sostenibilità rispetto alla farina di pesce. La farina di soia è la principale risorsa proteica vegetale per l’alimentazione animale, per il suo elevato contenuto proteico, il buon profilo amminoacidico, l’elevata digeribilità, il costo ridotto, nonché l’ampia disponibilità. La farina di soia contiene isoflavoni (genisteina, daidzeina, gliciteina) che sono composti polifenolici nonché fitoestrogeni ed in quanto tali possono agire come agonisti o antagonisti dei recettori degli estrogeni endogeni, agendo biologicamente sulla specie ittica e modificando le caratteristiche qualitative del prodotto finale. I potenziali effetti degli isoflavoni possono influenzare l’utilizzo della farina di soia come risorsa proteica alternativa nei mangimi per pesci. Risulta importante valutare per la sicurezza del consumatore anche il potenziale ammontare degli isoflavoni nel tessuto edibile della specie alimentata con la soia, oltre che il loro effetto antiossidante che potrebbe aumentare la shelf life del prodotto. Il nostro obiettivo si prefiggeva, da un lato, di esaminare l’effetto degli isoflavoni della soia sulla crescita, la riproduzione e la salute della trota iridea (Oncorhynchus mykiss), dall’altro, di valutare la qualità della carne del pesce. Le trote sono state alimentate con tre diete contenenti differenti concentrazioni di isoflavoni (0, 500, 1000 ppm) per un tempo di 70 giorni. Al termine della prova di alimentazione, una parte delle trote sperimentali sono state utilizzate per valutare la crescita, l’attività estrogenica (espressa in livelli di proteine del tuorlo nel plasma e nel fegato), i livelli plasmatici di estradiolo, lo sviluppo gonadico, lo stato di stress e i cambiamenti istologici nei vari tessuti. Analisi complementari su performance di crescita, composizione prossimale, ossidazione lipidica e deposito degli isoflavoni nel filetto sono state effettuate sulla rimanente parte delle trote, dopo la loro conservazione a 4°C, per 1 e 7 giorni. I diversi dosaggi di isoflavoni non hanno influenzato né la performance di crescita né le concentrazioni di mRNA del Fattore di Crescita Insulino Simile (Igf-I) nel fegato. I livelli della vitellogenina (VTG) in plasma e fegato e di estradiolo plasmatico (E2) non sono stati condizionati dalle diete utilizzate, inoltre la correlazione tra livello plasmatico di E2 e i valori densitometrici della VTG si è rivelata significativa (p < 0.05). L’indice gonadosomatico (GSI) delle trote non ha mostrato differenze tra i tre gruppi sperimentali ed è risultato correlato con i valori densitometrici della VTG plasmatica (p < 0.05). Le concentrazioni di cortisolo rilevate in plasma, muscolo e pinna si sono collocate in un range di valori bassi, compatibili con una condizione di benessere, e non hanno mostrato correlazioni con il livello di isoflavoni nelle diete. Dal punto di vista istologico, l’intestino distale presentava una morfologia normale con enterociti ben differenziati, così come il fegato che, a sua volta, mostrava epatociti normali. In tutti i gruppi testati, si è evidenziato un accumulo sopranucleare di gocce lipidiche che suggerisce un effetto dei lipidi della dieta basale sul trasporto/metabolismo dei grassi nel pesce. L’inclusione di differenti livelli di isoflavoni nelle diete non ha influenzato nemmeno la performance delle trote utilizzate per l’analisi del prodotto finale in momenti diversi durante la conservazione. Infatti, le trote mostravano un simile peso del corpo alla cattura, con una media di 337 g, ed una media del peso del corpo eviscerato di 229 g. Gli indici biometrici, il colore della pelle e del filetto, le caratteristiche reologiche, la composizione chimica e il profilo acidico dei grassi del filetto non sono stati modificati dai diversi trattamenti alimentari. D’altro canto, il tempo di conservazione ha ridotto significativamente la resa dei filetti (56.4 vs. 53.6%; p < 0.01) e la luminosità della pelle (59.2 vs 51.5; p < 0.001), l’indice del rosso ha mostrato valori più negativi (p < 0,001) e l’indice del giallo è diminuito (6.99 vs. 5.07; p < 0.001). Il pH del filetto (6.22 vs. 6.34; p < 0.001) e la sua luminosità sono aumentati (38 vs. 43.6; p < 0.001), mentre l’indice del giallo (6.20 vs. 4.52; p < 0.001) e lo sforzo di taglio sono diminuiti (0.94 vs. 0.80 g kg-1; p < 0.001). Sempre sulla base del tempo di conservazione, il filetto ha mostrato un aumento della percentuale d’acqua, una perdita in proteine ed un aumento del contenuto di azoto basico volatile (19.3 vs. 21.2 mg 100 g-1; p < 0.001). Durante la conservazione, inoltre, è risultata una diminuzione degli acidi grassi polinsaturi (PUFA) omega-6 (13.1% vs. 12.7 %; p < 0.05) e un aumento del rapporto omega-3/omega-6 (1.05 vs. 1.20; p < 0.05). I risultati hanno evidenziato, per entrambi i tempi di conservazione, un accumulo di isoflavoni nei filetti di trota, anche se la concentrazione non è stata influenzata significativamente dal contenuto degli isoflavoni presenti nelle diete. L’ossidazione lipidica, espressa come livelli di TBARS (thiobarbituric acid reactive substances), dei filetti conservati dopo 1 giorno di conservazione a 4 °C, è risultata significativamente più alta che al giorno 7 (p < 0.05), ma nessuna differenza si è riscontrata tra i gruppi alimentati con diversi livelli di isoflavoni, evidenziando nessun effetto da parte degli isoflavoni della soia sull’ossidazione lipidica del filetto. I risultati ottenuti sembrano indicare che gli isoflavoni, alle dosi testate, non compromettano la riproduzione, la crescita e la salute della trota; anche se si è osservato un moderato trasferimento degli isoflavoni dalla dieta al filetto, la qualità, le caratteristiche nutrizionali e l’ossidazione lipidica non risultano influenzati dal trattamento alimentare. In merito al contenuto di isoflavoni nella farina di soia e al loro potenziale effetto, i nostri risultati dimostrano che la farina di pesce può essere sostituita dalla farina di soia nelle diete somministrate alle trote senza aver effetti negativi sulla performance e sulla qualità del prodotto finale.

Les poudres laitières enrichies en matière grasse (MG) suscitent un intérêt croissant d'un point de vue économique et scientifique. Elle représentent une large gamme de produits, qui donnent lieu à de nombreues applications alimentaires parmi lesquelles les laits infantiles, les ingrédients laitiers, l'alimentation animale et les arômes encapsulés. La structure supramoléculaire de la MG dans les poudres enrichies en MG est souvent très complexe et mal connue. Elle confère à la MG des propriétés fonctionnelles de la matrice environnante. Malgré son intérêt, cette thématique n'a que peu été étudiée. De plus, le contrôle des propriétés physico-chimiques des poudres reste empirique dans le domaine industriel. Ainsi, il apparaissait primordial d'étudier les questions scientifiques en lien avec la structure supramoléculaire de la MG dans les poudres laitières, tant pour les communautés académiques qu'industrielles
Fat-filleddairy powders have acquired a growing interest from both an economical and a scientific point of view. They include a large variety of products for numerous food applications such as infant formulae, dairy ingredients, cattle feeding, and ecapsulated flavors. Fat supramolecular structure in fat-filled dairy powders can be very complex and is often poorly understood. It gives specific physicochemical properties to fat, which in turn gives specific functional properties to the surrounding matrix. Despite its interest, there was no exhaustive academic study of the topic at the beginning of this Ph. D. Program. Furthermore, controlling the physicochemical propoerties of these powders was still rather empirical in the industry. Hence, investigating the scientific issues related to fat supramolecular structure in fat-filled dairy powders appearead to be of primary importance for both the academic and industrial communities worldwide. The aims of this Ph. D. Research program were to investigate fat supramolecular structure and properties in fat-filled dairy powders in order (1) to determine adapted chemical compositions and process parameters to orientate fat supramolecular structure in fat-filled dairy powders, (2) to reach a better understanding of the mechanisms of the formation and evolution of fat supramolecular structure and fat physicochemical properties, and finally (3) to control powder physicochemical properties. The strategy was original as the study considered powders manufactured at the laboratory in controlled and industrial-like conditions and as specific methods for lipids were adapted to fat-filled dairy powders

Les travaux présentés dans cette thèse concernent l’étude et la fabrication de composants passifs hyperfréquence possédant un facteur de qualité important sur les bandes Q et V. Pour cela, nous nous sommes orientés vers la fabrication de composants volumiques à air. Des lignes coaxiales à section rectangulaire à air ainsi que des filtres à cavité métalliques à air ont été réalisés. Aussi, ces travaux consistent à définir une méthode de fabrication permettant d’obtenir les composants cités précédemment. Plusieurs techniques de micro-fabrication additives ont ainsi été établies afin de répondre à la problématique
This work concerns the study and the fabrication of passive RF components with a high quality factor on Q/V bands. The components were fabricated with an air-filled 3D architecture. Air-filled rectangular micro-coaxial lines and air filled cavity filters were demonstrated. Also, micro-additive fabrication processes were demonstrated for the realization of the 3D air-filled components

Le Québec se classe parmi les quatre provinces ayant un taux de grossesses à l'adolescence supérieur à la moyenne nationale. Les conséquences d'une grossesse à l'adolescence sont nombreuses et souvent néfastes non seulement pour la mère mais aussi pour le développement de l'enfant. Dans une optique de prévention à long terme, il est important d'approfondir nos connaissances des motivations qui incitent de jeunes adolescentes à devenir enceinte et à donner naissance à un enfant, et ce, afin de concevoir une approche d'intervention plus efficace que celle axée sur l'éducation sexuelle des filles. Cette étude a donc pour objectifs : (1) de vérifier si les jeunes mères ont des motivations de grossesse qui diffèrent des motivations des jeunes adultes qui n'ont jamais vécu de grossesse à l'adolescence ; (2) de confirmer si un attachement anxieux est associé au fait d'avoir ou non un enfant à l'adolescence ; et (3) d'examiner dans quelle mesure ces motivations sont associées à la qualité de la relation d'attachement qui unit ces jeunes filles à leur propre mère.

Представлено результати експериментального підтвердження математичної моделі прогнозування властивостей деталей, отриманих зі склонаповнених поліамідів в ультразвуковому полі. The experimental verification results of the mathematical model of properties machines details obtained by glass-filled polyamides in the ultrasonic field are presented.

The thesis deals with a draft production procedure for a specific welded component of a bearing console, including the consideration of the basic material welding quality, the selection of welding method and parameters, thermal processing, if applicable, and the selection of filler material. Draft welding procedure of WPS and weld check. Consideration of the use of a robot.

Orientador: Igor Paiva Ramos
Resumo: Empreendimentos hidroelétricos podem desencadear alterações no ciclo hidrológico, desequilíbrio dos ecossistemas aquáticos e facilitar a introdução de espécies de peixes não-nativas. Contudo, essas espécies também podem apresentar grande representatividade na pesca artesanal e esportiva, tornando-se uma importante fonte de renda local. Dessa forma, o estudo de espécies não-nativas, suas origens, hábitos e posições tróficas, além de suas habilidades que garantem a permanência e o sucesso no estabelecimento em novos ambientes, são relevantes. Dentre tais espécies não-nativas, Geophagus sveni destaca-se como uma das espécies mais importantes para pesca artesanal na região Noroeste do estado de São Paulo. O presente trabalho teve como objetivo caracterizar e correlacionar a composição alimentar, composição bromatológica do tecido muscular, perfil de ácidos graxos do tecido muscular e hepático, além de identificar possíveis parasitos musculares em G. sveni nos períodos chuvoso e seco, no reservatório de Jupiá, alto rio Paraná, Brasil. Foram realizadas duas coletas, uma ao final do período chuvoso (março/2018) e outra ao final do período seco (agosto/2018), no reservatório de Jupiá (20°30'33.4"S 51°27'19.7"W). Os espécimes coletados foram eutanasiados e, em seguida, tiveram mensuradas massa total, comprimento padrão e o sexo determinado visualmente. Geophagus sveni apresentou hábito alimentar detritívoro, além de plasticidade e oportunismo trófico. Sua composição alimentar foi sign... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Hydroelectric developments can trigger changes in the hydrological cycle, imbalance in aquatic ecosystems and facilitate the introduction of non-native fish species. However, these species can also be highly representative in artisanal and sport fishing, becoming an important source of local income. Thus, the study of non-native species, their origins, habits and trophic positions, in addition to their skills that guarantee permanence and success in the establishment of new environments, are relevant. Among these non-native species, Geophagus sveni is provided as one of the most important species for artisanal fisheries in the Northwest region of the state of São Paulo. This study aimed to characterize and correlate the food composition, the bromatological composition of muscle tissue, the fatty acid profile of the muscle and liver tissue, in addition to identifying possible muscle parasites of Geophagus sveni in the rainy and dry periods, in the Jupiá reservoir, on the Paraná River, Brazil. Two collections were made, one at the end of the rainy period (March/2018) and another at the end of the dry period (August/2018), at the Jupiá reservoir (20°30'33.4"S 51°27'19.7"W). The collected specimens were euthanized and, afterwards, total mass and standard length were measured, as well as sex determined visually. Geophagus sveni presented detritivorous eating habits, in addition to plasticity and trophic opportunism. Their food composition was significantly different only between t... (Complete abstract click electronic access below)
Mestre

En les últimes dècades, la qualitat de vida familiar (d'ara endavant QdVF) ha emergit com un constructe decisiu tant per millorar les condicions de vida de les famílies de persones amb discapacitat com per valorar els resultats dels serveis i suports que aquestes reben. La finalitat d'aquesta recerca ha estat, d'una banda, conèixer en quina mesura els suports que ofereixen els serveis d'atenció precoç - i altres serveis- s'adeqüen a les necessitats dels infants amb trastorns en el desenvolupament i de les seves famílies i, en conseqüència, tenen un impacte positiu en la QdVF; i de l'altra, explorar si la col•laboració entre les famílies i els professionals esdevé un factor fonamental que intervé en la percepció de la QdVF. Per poder respondre aquestes qüestions prèviament hem hagut d'adaptar i validar al context català els instruments Service Inventory (Beach Center, 2003), Beach Center Family-Professional Partnership (Summers el al., 2005) i Beach Center FQOI. (Hoffman et al., 2006) i crear uns indicadors complementaris per millorar la informació derivada d'aquestes escales. La investigació s'ha dut a terme amb la col•laboració de 202 famílies d'infants amb trastorns en el desenvolupament de 0 a 6 anys que assisteixen a 13 centres de desenvolupament infantil i atenció precoç. Metodològicament, la investigació és de naturalesa descriptiva i explicativa/estructural. Per conèixer la influència que l'adequació dels suports i la col•laboració famílies -professionals exerceixen en la QdVF hem fet ús del Model d' Equacions Estructurals. Els resultats obtinguts en la recerca posen de manifest, en primer lloc, que els tres instruments adaptats s'adeqüen amb èxit a la població catalana i que els índexs dissenyats han resultat ser una molt bona solució per facilitar l'avaluació i la interpretació dels constructes que les escales anteriors pretenen mesurar. En segon 1loc, que la percepció de les famílies és que els serveis no acaben de donar una resposta com pleta a les necessitats particulars dels seus fills i del conjunt de la família. En tercer lloc, que la col•laboració que mantenen amb els professionals és relativament bona i que estan raonablement satisfetes amb la seva QdVF. Finalment, que l' adequació dels suports ha resultat ser un bon predictor de la QdVF i que la col•laboració es revela un dels factors clau que fa de mitjancer d'aquest efecte. En síntesi, assolir els objectius que ens hem proposat ha de permetre que els professionals dels serveis i les institucions públiques es trobin en condicions més favorables per dissenyar propostes de millora pels serveis d'atenció precoç, amb la finalitat que la qualitat de vida d'aquestes famílies i el progrés dels infants amb discapacitat que viuen a Catalunya es vegi progressivament potenciada i incrementada.
En las últimas décadas, la calidad de vida familiar (en adelante CdVF) ha emergido como un constructo decisivo tanto para mejorar las condiciones de vida de las familias de personas con discapacidad como para valorar los resultados de los servicios y apoyos que estas reciben. La finalidad de esta investigación ha sido, por una parte, conocer en qué medida los apoyos que proporcionan los servicios de atención temprana - y otros servicios- se adecúan a las necesidades de los niños con trastornos en el desarrollo y a las de sus familias y, en consecuencia, tienen un impacto positivo en la CdVP; por otra, explorar si la colaboración entre las familias y los profesionales aparece como un factor fundamental que interviene en la percepción de la CdVF. Con el fin de responder estas cuestiones previamente nos hemos visto con la necesidad de adaptar y validar al contexto catalán los instrumentos Service Inventory (Beach Center, 2003), Beach Center Family-Profesi onal Partnership (Summers et al., 2005) y Beach Center FQOL (Hoffman el al., 2006) y crear unos índices complementarios para mejorar la información derivada de estas escalas. La investigación se ha llevado a cabo con la colaboración de 202 familias de niños con trastornos en el desarrollo de 0 a 6 años que asisten a 13 centros de atención temprana. Metodológicamente, la investigación es de naturaleza descriptiva y explicativa/estructural. Para conocer la influencia que la adecuación de los apoyo s y la colaboración familias-profesionales ejercen en la CdVF nos hemos basado en la técnica de análisis de datos del Modelo de Ecuaciones Estructurales. Los resultados obtenidos ponen de manifiesto, en primer lugar, que los tres instrumentos adaptados se ajustan a la población catalana y que los índices diseñados han resultado ser una muy buena solución por facilitar la evaluación y la interpretación de los constructos que las escalas anteriormente citadas pretenden medir. En segundo lugar, que la percepción de las familias es que los servicios no acaban de dar una respuesta completa a las necesidades particulares de sus hijos y del conjunto de la familia. En tercer lugar, que la colaboración que las familias mantienen con los profesionales es relativamente buena y que están razonablemente satisfechas con su CdVF. Finalmente, que la adecuación de los apoyos resulta ser un predictor de la CdVF y que la colaboración es uno de los factores esenciales que media este efecto. En síntesis, dar respuesta a los objetivos propuestos debería permitir que los profesionales de los servicios y las administraciones estén en condiciones más favorables para diseñar propuestas de mejora para los servicios de atención temprana, con el fin de que la calidad de vida de estas familias y el progreso de los niños con discapacidad que viven en Catalunya se vea progresivamente potenciados e incrementados.
In recent decades, the Family Quality of Life (FQOL) has emerged as a decisive construct, both to improve the condition of lire of the families of persons with disabilities and to assess the results of services and supports that they receive. The aim of this research is twofold: to identify to what extent early childhood intervention center supports - and those of other services - meet the needs of children with intellectual and developmental disabilities and their families and, as a result, have a positive impact on the FQOL; and to explore whether the partnership between families and professionals has become a fundamental mediator factor of the perception of FQOL. In order to answer these questions we had to adapt and validate the instruments Service Inventory (Beach Center, 2003), Beach Center Family-Professional Partnership (Summers et al., 2005) and Beach FQOL (Hoffman et al., 2006) to the Catalan context, and we had to create complementary indexes to improve upon the information stemming from these scales. This study was conducted in collaboration with 202 families with children with intellectual disabilities ranging in age from 0 to 6 years, who attended 13 early childhood intervention centers. Methodologically, this study is descriptive and explanatory/structural; we used the Structural Equation Models to identify the influence that the adequacy of supports and the partnerships exert on the FQOL. The results obtained from the research show that, firstly, the three adapted instruments were successfully used with the Catalan population, and that the designed indexes turned out to be a good solution for evaluating and interpretating the constructs that the previous scales tried to measure, Secondly, the families' perception is that the centers do not provide a complete answer to the specific needs of their children nor of the family as a whole. Thirdly, the partnerships held with professionals arerather good, and the families are reasonably satisfied with their FQOL. Finally, the supports’ adaptation turned out to be a good predictor of the FQOL and that these partnerships have become one of the key factors that mediate on this effect. In brief, achieving the set goals that we have set forth must allow service professionals and public bodies to be in a more favourable positions lo design policies to improve early childhood intervention centers, to the end that the quality of life of these families and the progress of children with disabilities living in Catalonia will be progressively strengthened and increased.

Orientador: Prof. Dr. José Luis Azcue Puma
Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia Elétrica, 2017.
Nas ultimas decadas, a utilização de cargas não lineares foi crescendo por causa das vantagens que oferecem, mas esse aumento acabou gerando efeitos adversos na qualidade da corrente da rede eletrica, quando estas duas estão em paralelo, afetando assim parametros de amplitude, forma de onda, frequencia e/ou simetria. Sendo os harmonicos, geradores de distorção e prejudicando especificamente o parametro da forma de onda, dependendo da carga e do numero de fases utilizadas. Nesta presente dissertação e apresentado o estudo de um sistema fotovoltaico com funçõess de filtro de harmonicos de corrente com o objetivo de não somente injetar potencia ativa na rede eletrica, se não, tambem de compensar os harmonicos que sao gerados pela carga (nao linear) e, comparar com um sistema fotovoltaico convencional tambem conectado à rede eletrica. O conversor Boost conectado diretamente com o arranjo fotovoltaico possui a função de rastrear o ponto de maxima potencia, empregando duas malhas de controle (a primeira para o controle de corrente utilizando o controlador 2P2Z e a outra para o controle de tens~ao utilizando o controlador PI), entanto que, o inversor trifasico tem a função de controlar a tensão no barramento CC, injetar potencia ativa na rede eletrica e filtrar as harmonicas de corrente geradas pela carga não linear. Na simulassão empregados tres tipos de carga, sendo uma linear R e duas não lineares RL e RC com retificador. Dessa forma, pode-se realizar a comparação entre os resultados obtidos para cada tipo de carga nos diferentes sistemas, e assim, analisar o espetro de frequencia da corrente na rede eletrica com a ferramenta FFT Analysis de Matlab, e tambem verifiar a diferença entre as potências ativa e reativa (do inversor trifásico, da carga e da rede eletrica) nas diferentes simulações. Verificou-se atraves dos resultados das simulações que a incorporação das funções de filtro no inversor fotovoltaico auxiliou na redução dos harmônicos de corrente, gerados pela carga não linear, injetados na rede elétrica.
With the advancements of communication technology and the constant need for high rates of data transfer, wireless communication is consistently the main and favorite option for the most kind of applications. By combining agility, performance and fast installation, it is often found in control systems, audio and television systems, internet access, etc. However, due to the imperfections and noise in the channel, this communication requires an eficient modulation and an adequate protection against errors in the data transmission. The IEEE 802.11g standard, also used in practically all modern communication systems and widely difused by the networks known as WiFi, appears as a perfect solution, since it allows to align robust and eficient techniques such as OFDM modulation and Convolutional coding. Using digital concept and the dynamic behavior of wireless communication, the concept of SDR (Software Dened Radio) becomes an interesting and powerful tool because the possibility of simulation and implementation of transceivers for several applications in a single device. This project aims to make a wireless IEEE 802.11g communication system using Software Defined Radios focusing on low cost radios and high performance to make the interface between the real world and the digital signal processing.

In the world there are adverse climates, climates that hinder the good construction and paving of roads, generating insecurity among the locals and visitors. This over time affects the economy of a country, as a road boosts tourism, transport and commerce. Therefore, a mixture was designed to mitigate a problem in the placement of hot asphalt mixture at temperatures below zero degrees Celsius. That is, a conventional mix design was proposed, but with different types of filler (lime, Portland cement type I and silica) tested with the Marshall and Lottman method which are governed according to the EG-2013 standards [1] and parameters established in the Asphalt Institute [2]. To find the optimum, it was tested with 5.0%, 5.5% 6.0% and 6.5% asphalt cement. Then with the results obtained a comparative analysis was performed. Finally, specimens without any additives were made, the specimens once prepared at 140°C were subjected to freezing, resulting in the three types of filler, that the hot asphalt mixture with incorporation of Portland cement type I to a 5, 90% of asphalt cement is the optimum since, subject to extreme temperatures below 0°C they comply with the parameters required in the standards.

The plastics industry is one of the fastest growing major industries in the world. There is an increase in the amount of plastic used for all types of products due to its light weight and ability to reprocess. For this reason, the reprocessing of thermoplastics and the usability of reprocessed materials are gaining significance, and it is important to produce and consume plastic materials in an environmentally friendly way. In addition, rising raw material cost linked to the increased oil prices encouraged for reusing of the plastic materials. The aim of this research was to study and optimize the injection moulding process parameters to achieve a trade-off between the product cost and product quality, measured through mechanical properties and geometry, based on using regrind ratios. The work was underpinned by a comprehensive study of multiple reprocessing effects in order to evaluate the effect of process parameters, material behaviour, reprocessing effects and possible links between the processing parameters and key properties. Experimental investigations were carried out, in particular, focused on the melt preparation phase to identify key process parameters and settings. Multiple reprocessing stages were carried out; using two types of PP material: unfilled and short glass filled. A series of tests were used to examine product quality (mass, colour and shrinkage) and physical properties (density, crystallinity, thermal stability, fibre length, molecular weight, in-line and off-line viscosity, tensile strength, modulus of elasticity, elongation (%) and flexural strength). This investigation showed that the mouldability of the filled and unfilled PP materials, through the successive reprocessing stages (using 100 % regrind), was observed to be relatively consistent. Given the link between the processing parameters and key product and material properties, it is possible to manufacture products with minimal loss to part quality and mechanical properties. The final phase of the work focused on process optimisation study for short glass fibre filled PP material and the identified key process parameters (melt temperature, screw rotational speed, holding pressure, holding time and injection rate). A response surface experiment was planned and carried out for three reprocessing stages (0 %, 25 % and 50 % regrind). The fitted response surface models were utilised to carry out the trade-off analysis between the operating cost (material cost, energy cost and labour cost) and product quality (dimensions and tensile strength) Based on the optimal moulding conditions, the operating cost was reduced (from stage I as a reference), by 24% and 30 % for stage II and stage III respectively. A small, perhaps undetectable, change in product dimensions was noted. In addition, a small reduction in tensile strength was noted (from stage I as a reference), by 0.4% and 0.1 % for stage II and stage III respectively. The same data was applied in other countries (Australia, USA, Brazil, Libya and China) to manufacture the same product; and it was observed that the cost was reduced with increasing of regrind ratio. But the significant reduction of the cost, essentially, depended on those countries which have low wage rates (e.g. Brazil, Libya and China). For example, the cost of moulded product manufactured in China is £ 0.025 (using 50% of regrind), while the cost of the same product produced in Australia is £ 0.12, hence giving a total saving of 79 % and making it a valuable issue to be considered in industry.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Nile tilapia (Oreochromis niloticus) is one of the most commercially cultivated species in the world, being preferred for its high rusticity and adaptability, fast growth and meat with desirable characteristics, such as low in fat, absence of "Y" spines and firm texture, much appreciated by consumers, which generates good acceptance in the market. To boost animal production, nutritional aids are sought for the animal diet in order to maintain fish health, obtain better rates of zootechnical performance and satisfactory meat quality. Fish oil, a by-product of the fishing industry, has been used as a supplement in animal feed and is recognized for its positive effects also on human health, since it is rich in polyunsaturated fatty acids of the family omega 3, effectively acting in the reduction of incidence of cardiovascular diseases, rheumatic disorders of the nervous system, promoting the strengthening of the immune system. Thus, it is through dietary supplementation of Nile tilapia with fish oil that a greater increase of fatty acids essential to their meat is sought in order to add value to the product and reaffirm it as a functional nutraceutical food, able to provide benefits to the human health, especially by preventing and reducing risks of disease. For this, different levels of inclusion of fish oil in the tilapia ration (5%, 10% and 15%) were tested for periods of 30 and 60 days pre-slaughter. At the end of the experiment, the economic evaluation was carried out, as well as the verification of the blood biochemistry and the indices of productive performance. After the fish were slaughtered and filleted, the steaks were properly packed and stored in freezing temperatures at -40°C for the subsequent physical-chemical analysis of the meat, covering the profile of fatty acids, centesimal composition, mineral elements content, cholesterol, vitamin E, lipid oxidation, color, pH, and texture-related characteristics such as weight loss by thawing, weight loss by cooking, water retention capacity, total and soluble collagen content, and myofibrillar fragmentation index. The treatments with fish oil were significant (P<0.05) only as regards the meat mineral content and the nutritional quality of the fillet lipid profile. For the other attributes, there were positive tendencies to meat quality, since it presented low fat and cholesterol content, a satisfactory centesimal composition for the species, efficient oxidative stability and a lighter fillet coloration with yellowish tones compatible with the taste of the consumer. Regarding the firmness of the fish meat, no influences of the supplemented feed on the analyzes were verified. However, texture improvement was noted due to the increase in CRA, which makes the product more succulent, and greater shear force in products submitted to the cooking process.
A tilápia do Nilo (Oreochromis niloticus) é uma das espécies mais cultivadas comercialmente no mundo, sendo preferida pela sua alta rusticidade e adaptabilidade, crescimento rápido e carne com características desejáveis, tais como baixo teor de gordura, ausência de espinhos em "Y" e de textura firme, muito apreciada pelos consumidores, o que gera boa aceitação no mercado. Para potencializar a produção animal, busca-se auxílios nutricionais para a dieta animal com o intuito de manutenção da saúde dos peixes, obtenção de melhores índices de desempenho zootécnico e satisfatória qualidade da carne. O óleo de peixe, subproduto da indústria pesqueira, tem sido utilizado como suplemento na alimentação animal, sendo reconhecido pelo seus efeitos positivos também na saúde humana, já que é rico em ácidos graxos poli-insaturados da família ômega 3, agindo eficazmente na redução da incidência de doenças cardiovasculares, reumáticas, distúrbios do sistema nervoso, promovendo ainda o reforço do sistema imune. Assim, é através da suplementação dietética de tilápias do Nilo com óleo de peixe que busca-se maior incremento de ácidos graxos essenciais à sua carne, a fim de agregar valor ao produto e reafirmá-lo como alimento nutracêutico funcional, apto a proporcionar benefícios à saúde humana, especialmente prevenindo e reduzindo riscos de enfermidades. Para isso, foram testados diferentes níveis de inclusão de óleo de peixe na ração para tilápias (5%, 10% e 15%) por períodos de 30 e 60 dias pré-abate. Ao final do experimento, realizou-se a avaliação econômica, bem como a verificação da bioquímica sanguínea e dos índices de desempenho produtivo. Após o abate e filetagem dos peixes, os filés foram devidamente embalados e armazenados em temperatura de congelamento a -40°C para posterior análise físico-química da carne, abrangendo o perfil de ácidos graxos, composição centesimal, teor de elementos minerais, de colesterol, de vitamina E, oxidação lipídica, cor, pH, além de características associadas à textura, como perda de peso por descongelamento, perda de peso por cocção, capacidade de retenção de água, conteúdo de colágeno total e solúvel, e índice de fragmentação miofibrilar. Os tratamentos com óleo de peixe foram significativos (P<0,05) apenas quanto ao teor de minerais da carne e a qualidade nutricional do perfil lipídico do filé. Para os demais atributos, observou-se tendências positivas à qualidade da carne, uma vez que esta apresentou baixos teores de gordura e colesterol, composição centesimal satisfatória para a espécie, estabilidade oxidativa eficiente e coloração do filé mais clara à tons amarelados, compatíveis com o gosto do consumidor. Quanto à firmeza da carne dos peixes, não foram verificadas influências da alimentação suplementada sobre as análises realizadas. Notou-se, entretanto, melhoria da textura devido ao aumento da CRA, o que torna o produto mais suculento, e força de cisalhamento maior em produtos submetidos ao processo de cozimento.

La qualitat de vida relacionada amb la salut (QVRS) en els nens amb paràlisi cerebral infantil (PCI) es pot veure afectada i les percepcions entre els nens i els seus pares poden variar. Els objectius generals d'aquest estudi han estat dos. El primer, mesurar la QVRS dels nens amb PCI i comparar-la amb la d'un grup control format per nens sense cap discapacitat. El segon, determinar el grau d'acord entre fills i pares. Com a objectius específics, es pretenen observar les diferències entre les percepcions dels pares del grup amb PCI i el grup control, analitzar la influència de variables sociodemogràfiques com l'edat i el gènere així com estudiar la possible influència del grau d'afectació motora. Es tracta d'un estudi transversal, quasi-experimental, compost de 288 participants. El grup de nois i noies amb PCI ha estat format per 50 participants, el 56% nois i 44% noies, amb una mitjana d'edat de 11,60 anys (SD: 2,44). La participació dels progenitors va ser del 100% de les mares i el 84% dels pares. El grup control ha estat format per 50 participants, 62% nois i 38% noies, amb una mitjana d'edat de 11,80 anys (SD: 2,47). La participació dels progenitors va ser del 98% de les mares i del 94% dels pares. L'instrument utilitzat ha estat el Kidscreen-52, desenvolupat per The Kidscreen Group Europe (2001-2004). Es tracta d'un instrument genèric dissenyat per mesurar la QVRS en població infantil i adolescent. Per mesurar el nivell d'afectació motora dels participants amb PCI s'ha utilitzat el Gross Motor Function Classification System (GMFCS). Els nois i noies amb PCI perceben una inferior QVRS concretament en dos dominis, en el de "Benestar psicològic", en el que principalment són les noies les que refereixen una significativa menor valoració en relació a les noies sense PCI, i en el de " Benestar físic ", en el qual principalment són els nois els que valoren significativament per sota que els nois sense PCI. Per contra, els nois amb PCI puntuen significativament per sobre que els seus iguals del grup control en el domini de "Relació pares i vida familiar". La valoració dels progenitors és globalment més negativa que la dels propis nois i noies amb PCI, sent-ho especialment la de les mares. Pares i mares coincideixen en infravalorar els dominis de "Benestar físic", "Autopercepció", Autonomia "i Amics i suport social". Les mares, a més, també infravaloren els dominis de "Benestar psicològic" i "Recursos econòmics". En comparar les valoracions entre grups de progenitors, els resultats mostren valoracions inferiors per part dels progenitors del grup amb PCI, i especialment per part de les mares. No es troben diferències en funció del gènere ni en el grup de nois i noies amb PCI, ni en el control. En el cas dels progenitors amb PCI, les mares puntuen significativament per sota que els pares en els dominis de "Benestar psicològic", "Estat d'ànim" i "Amics i suport social". En el grup sense PCI les mares valoren per sobre que els pares en domini de "Amics i suport social". Pel que fa a l'edat, en el grup amb PCI no es donen diferències entre el grup de 8 a 12 anys i el grup 13 a 18 anys. En el grup control es troba menors puntuacions per al grup d'edat entre 13 i 18 anys a 6 dominis: "Benestar físic", "Benestar psicològic", Autopercepció "," Autonomia "," Relació pares i vida familiar " i " Entorn escolar ". Centrant-nos en la influència del grau d'afectació motora dels participants del grup amb PCI, es troba valoracions significativament menors per part del grup amb una major afectació (nivells III / IV / V al GMFCSPC) a "Autonomia" i "Relació pares i vida familiar ". En el cas dels progenitors, les puntuacions són significativament inferiors en el domini de "Benestar físic" per al grup amb major afectació motora. Les troballes suggereixen que els nois i noies amb PCI no perceben una pitjor QVRS en general que els nois i noies sense discapacitat, però concretament el seu benestar físic i benestar psicològic es veuen condicionats de manera negativa. Per contra, aquest grup experimenti una major satisfacció pel que fa a la relació amb els pares i la vida familiar. Els pares dels nois i noies amb PCI infravaloren QVRS dels seus fills, de manera que les seves percepcions no són equivalents però si complementàries. Això pot estar relacionat amb la seva diferent posició, grau de maduresa i expectatives. L'impacte de la discapacitat es viu de manera diferent en funció del gènere. L'edat no és un factor condicionant de la QVRS en el grup amb PCI, probablement per les alteracions en el desenvolupament maduratiu i el nivell de consciència, però si ho és en el grup control, veient-se afectada en les etapes de la preadolescència i adolescència. El grau d'afectació motora dificulta el desenvolupament de l'autonomia i de la dinàmica familiar des del punt de vista del fill, i des del punt de visa del pare, influeix en el benestar físic. Els progenitors de tots dos grups tendeixen a infravalorar el benestar psicològic dels seus fills. Es posa en evidència que per als nois i noies, més enllà de si hi ha una discapacitat, la vivència del sentir-se acceptat a nivell social és un factor controvertit. Així mateix, per a tots els nois i noies, l'entorn escolar és font de satisfacció, així com també ho és l'entorn d'amistats i la sensació de suport social. Els progenitors en canvi, valoren que fa a l'entorn escolar però infravaloren les relacions d'amistat i el suport social amb el qual els seus fills compten. Finalment, es posa en evidència la necessitat de seguir desenvolupant programes d'intervenció des dels diferents organismes socials amb el objectius de, per una banda, aconseguir una igual QVRS per als nois i noies amb PCI, i de l'altra, atendre i afavorir el benestar psicològic, el desenvolupament personal i l'autonomia, de tots els membres d'una família en la qual es troba un fill amb PCI.
La calidad de vida relacionada con la salud (CVRS) en los niños con parálisis cerebral infantil (PCI) puede verse afectada y las percepciones entre los niños y sus padres pueden variar. Los objetivos generales de este estudio han sido dos. El primero, medir la CVRS de los niños con PCI y compararla con la de un grupo control formado por niños sin ninguna discapacidad. El segundo, determinar el grado de acuerdo entre hijos y padres. Como objetivos específicos, se pretenden observar las diferencias entre las percepciones de los padres del grupo con PCI y el grupo control, analizar la influencia de variables sociodemográficas como la edad y el género, así como estudiar la posible influencia del grado de afectación motora. Se trata de un estudio transversal, casi-experimental, compuesto de 288 participantes. El grupo de chicos y chicas con PCI ha estado formado por 50 participantes, 56% chicos y 44% chicas, con una media de edad de 11,60 años (SD: 2,44). La participación de los progenitores fue del 100% de las madres y del 84% de los padres. El grupo control ha estado formado por 50 participantes, 62% chicos y 38% chicas, con una media de edad de 11,80 años (SD: 2,47). La participación de los progenitores fue del 98% de las madres y del 94% de los padres. El instrumento utilizado ha sido el Kidscreen-52, desarrollado por The Kidscreen Group Europe (2001-2004). Se trata de un instrumento genérico diseñado para medir la CVRS en población infantil y adolescente. Para medir el nivel de afectación motora de los participantes con PCI se ha utilizado el Gross Motor Function Classification System (GMFCS). Los chicos y chicas con PCI perciben una inferior CVRS concretamente en dos dominios, en el de “Bienestar psicológico”, en el que principalmente son las chicas las que refieren una significativa menor valoración en relación a las chicas sin PCI, y en el de “Bienestar físico”, en el cual principalmente son los chicos los que valoran significativamente por debajo que los chicos sin PCI. Por el contrario, los chicos con PCI puntúan significativamente por encima que sus iguales del grupo control en el dominio de “Relación padres y vida familiar”. La valoración de los progenitores es globalmente más negativa que la de los propios chicos y chicas con PCI, siéndolo especialmente la de las madres. Padres y madres coinciden en infravalorar los dominios de “Bienestar físico”, “Autopercepción”, Autonomía” y Amigos y apoyo social”. Las madres, además, también infravaloran los dominios de “Bienestar psicológico” y “Recursos económicos”. Al comparar las valoraciones entre grupos de progenitores, los resultados muestran valoraciones inferiores por parte de los progenitores del grupo con PCI, y en especial por parte de las madres. No se encuentran diferencias en función del género ni en el grupo de chicos y chicas con PCI, ni en el control. En el caso de los progenitores con PCI, las madres puntúan significativamente por debajo que los padres en los dominios de “Bienestar psicológico”, “Estado de ánimo” y “Amigos y apoyo social”. En el grupo sin PCI las madres valoran por encima que los padres en dominio de “Amigos y apoyo social”. Por lo que se refiere a la edad, en el grupo con PCI no se dan diferencias entre el grupo de 8 a 12 años y el grupo 13 a 18 años. En el grupo control se encuentra menores puntuaciones para el grupo de edad entre 13 y 18 años en 6 dominios: “Bienestar físico”, “Bienestar psicológico”, Autopercepción”, “Autonomía”, “Relación padres y vida familiar” y “Entorno escolar”. Centrándonos en la influencia del grado de afectación motora de los participantes del grupo con PCI, se encuentra valoraciones significativamente menores por parte del grupo con una mayor afectación (niveles III/IV/V en el GMFCS) en “Autonomía” y “Relación padres y vida familiar”. En el caso de los progenitores, las puntuaciones son significativamente inferiores en el dominio de “Bienestar físico” para el grupo con mayor afectación motora. Aunque los resultados no son definitivos debido a las limitaciones de la muestra, se intuye menores puntuaciones en la CVRS de los chicos y chicas con PCI sin hermanos, y no se dan diferencias en función del estado civil de los padres. Los hallazgos sugieren que los chicos y chicas con PCI no perciben una peor CVRS en general que los chicos y chicas sin discapacidad, pero concretamente su bienestar físico y bienestar psicológico se ven condicionados de manera negativa. Por el contrario, este grupo experimente una mayor satisfacción en cuanto a la relación con sus padres y la vida familiar. Los padres de los chicos y chicas con PCI infravaloran CVRS de sus hijos, de manera que sus percepciones no son equivalentes pero si complementarias. Esto puede estar relacionado con su distinta posición, grado de madurez y expectativas. El impacto de la discapacidad se vive de manera distinta en función del género. La edad no es un factor condicionante de la CVRS en el grupo con PCI, probablemente por las alteraciones en el desarrollo madurativo y el nivel de consciencia, pero si lo es en el grupo control, viéndose afectada en las etapas de la preadolescéncia y adolescencia. El grado de afectación motora dificulta el desarrollo de la autonomía y de la dinámica familiar desde el punto de vista del hijo, y desde el punto de visa del padre, influye en el bienestar físico. Los progenitores de ambos grupos tienden a infravalorar el bienestar psicológico de sus hijos. Se pone en evidencia que para los chicos y chicas, más allá de si existe una discapacidad, la vivencia del sentirse aceptado a nivel social es un factor controvertido. Así mismo, para todos los chicos y chicas, el entorno escolar es fuente de satisfacción, así como también lo es el entorno de amistades y la sensación de apoyo social. Los progenitores en cambio, valoran lo referente al entorno escolar pero infravaloran las relaciones de amistad y el apoyo social con el que sus hijos cuentan. Finalmente, se pone en evidencia la necesidad de seguir desarrollando programas de intervención desde los distintos organismos sociales con el objetivos de, por un lado, conseguir una igual CVRS para los chicos y chicas con PCI, y por el otro, atender y favorecer el bienestar psicológico, el desarrollo personal y la autonomía, de todos los miembros de una familia en la que se encuentra un hijo con PCI.
The quality of life related to health (HRQL) in children with cerebral palsy (CP) could be affected and perceptions among children and their parents could vary. This study has two main objectives. The first objective is to measure the HRQL of children with PCI and compare it with a control group of children without disabilities. The second objective is to assess the level of agreement between children and parents. The specific objectives are intended to observe the differences between the perceptions of parents of group with PCI and the parents of the control group, analyze the influence of sociodemographic variables such as age and gender and study the possible influence of the motor impairment level. This cross-sectional study, quasi-experimental, included a total of 288 participants. The group of boys and girls with PC was made up of 50 participants, 56% boys and 44% girls, with an average age of 11.60 years (SD: 2.44). The involvement of parents was 100% of mothers and 84% of fathers. The control group was made up of 50 participants, 62% boys and 38% girls, with an average age of 11.80 years (SD: 2.47). The participation of the parents was 98% of mothers and 94% of fathers. The instrument used was the Kidscreen-52, developed by The Kidscreen Group Europe (2001-2004). This is a generic instrument designed to measure the HRQL in child and adolescent population. To measure the level of motor involvement of participants with PC it was used Gross Motor Function Classification System (GMFCS). The boys and girls with PC perceive a lower HRQL specifically in two domains. In “Psychologic well-being”, the girls are mainly who reported a significantly lower valuation in relation to the girls without PC, and in “Physical well-being “, the boys are mainly the ones who value lower than boys without PC. By contrast, children with PC scored higher than their peers in the domain of “Parent relation and home life”. We found that parental perspectives were generally more negative than those of the boys and girls with PC, especially the mothers remain so. Fathers and mothers agree underestimate domains “Physical well-being”, “Self-perception”, “Autonomy“ and “Social support and peers.” Mothers also underestimate “Psychological well-being” and “Financial resource”. Comparing valuations between groups of parents, results show lower valuations by the parents of the PC group, especially by mothers. No differences were found by gender, nor the group of boys and girls with PC, nor control group. For parents with PC, mothers scored significantly lower than fathers in the domains of “Psychological well-being”, “Moods and emotions” and “Social support and peers”. In the group without PC, mothers valued above the fathers “Friends and social support.” No differences were found regarding the age influence between PC group aged 8 to 12 and the group aged 13 to 18. By contrast, in the control group lower scores were found in 6 domains for the group aged 13 to 18: “Physical well-being”, “Psychological well-being,” Self-perception “,” Autonomy “,” Parent relation and home life” and “School Environment” Focusing on the motor impairment level influence of participants in the group with PC, it is significantly lower valuations by the group with greater impairment (level III / IV / V in the GMFCS) on “Autonomy” and “Parent relation and home life”. For parents, the scores are lower in the domain of “Physical well-being” for the group with greater motor impairment. The findings suggest that boys and girls with PC not perceive a worse overall HRQL than boys and girls without disabilities, but particularly their physical and psychological well-being are negatively conditioned. On the contrary, this group experienced greater satisfaction in the relationships with their parents and home life. Parents of boys and girls with PC underestimate their children HRQL, so their perceptions are not equivalent but the can be considered complementary. This may be related to their different vital position, maturity and expectations. The impact of disability is experienced differently by gender. Age is not a determining factor of HRQL in the PC group, probably by alterations in the development and the level of consciousness, but it is in the control group were a lower scores are found in the preadolescence and adolescence stages. The motor impairment level hinders the development of autonomy and family dynamics from the point of view of the child, and from parents’ point of view affects to the physical well-being. Parents of both groups tend to underestimate the psychological well-being of their children. It shows that for boys and girls, beyond disability, the experience of feeling socially accepted is a controversial factor. Likewise, for all boys and girls the school environment is a source of satisfaction, and so is the environment of friends and the feeling of social support. Parents also value successfully the school environment but underestimate the friendship relations and social support that their children have. Finally, it is highlighted the need to develop intervention programs from different social organizations with the objective of, achieve equal HRQL for boys and girls with PC, and serve and promote the psychological well-being, personal development and empowerment of all members of a family with a child with PC.

Soil organic matter loss is a widely recognized European soil threat and intensive and repeated tillage operations are known to negatively affect numerous soil properties and ecosystem services. In this view, the study on more sustainable agronomic managements is a pressing need for research community. Between sustainable techniques, conservation agriculture (CA) is nowadays a spread technique based on three main pivotal points: 1) minimum soil disturbance, 2) permanent soil covering and 3) crop diversification. CA is often associated with numerous soil functions such as increasing of soil biodiversity, organic matter stocks and aggregate stability and decreasing of runoff, erosion and P losses and dioxide carbon emissions. Despite the first estimates, CA practices are recently not recognized as a win-win solution for climate mitigation and agro-ecosystem improvement because the absence of tillage operations may impact the crop root growth through an increase in soil strength and bulk density, and reduce soil porosity and gas exchanges and lastly, the overall benefits of CA have been strictly related to soil type and climate. Within this viewpoint of not consistent results, more research is needed to understand and optimize the potential of sustainable agronomic practices. For these reasons, in this work, a field experiment was conducted including four farms on the low-lying plain of Veneto Region characterized by silty soils, in which conservation agriculture practices (no-tillage, cover crops and residues retention) were applied and compared to conventional tillage system. The first objective of the thesis was to evaluate the effects of CA practices on C cycle. The soil organic carbon (SOC) evolution in terms of both stock quantity and quality was monitored over a 3-yr transition period. The SOC stock was quantified through an equivalent soil mass approach up to 50 cm depth while the influence of each CA component was disentangled considering crop, cover crop and root biomasses, and tillage type as separate factors. The SOC quality was evaluated through humic carbon, its molecular weight distribution and microbial biomass analyses. The study showed that after short period, CA adoption did not increase C stock but rather its distribution within the soil profile while a positive effect was observed on humic carbon with the production of more polycondensed humic substances. The second objective regarded the evaluation of the soil gas exchange properties in the poorly structured silty soils of the low-lying plain. The effect of conservation agriculture practices on soil pore and gas transport characteristics was studied through the analyses of air permeability, gas diffusivity and air-filled porosity, and the derivation of soil structure indices on 144 undisturbed 100 cm3 soil cores. Gas transport measurements highlighted low transmission properties of the silty soils independently from agronomic management leading to critical value for both soil aeration and microbial aerobic activity. The third objective focused on the characterisation of the soil structure evolution after 5-yr of conservation agriculture management adoption. The soil pore network was quantified coupling mercury intrusion porosimetry and x-ray micro-tomography to study the total porosity and size distribution, from the macro- to the ultramicro- scale, and its architecture, on 96 undisturbed soil samples collected in the field experiment. Results suggested that silty soils of Veneto plain are micro-structured since much of the porosity is in the 0.0074-30 μm range and CA practices showed a positive influence on the ultramicroporosity range (0.1-5 μm) which are strictly linked to SOC stabilization. Concluding, silty soils of the Veneto region low-lying plain showed a slow reaction to conservation agriculture practices, as demonstrated by the poor effect on C sequestration, gas-transport characteristics and soil structure improvements. The limited amount of non-complexed organic carbon available for interaction with the soil fines prevented the formation of a more resilient soil structure leading to soil compaction that negated the exploitation of CA-related benefits. Despite such mechanisms, CA practices positively influenced C quality and ultramicroporosity range suggesting that a virtuous cycle between SOC and soil structure has been initiated. Longer transition period will be needed to reach a favourable equilibrium in the CA systems and more studies elucidating the mechanisms of structure improving conditions for silty soils, such as those examined in this study, are also required.
La perdita di sostanza organica è una delle minacce del suolo riconosciute a livello europeo e le ripetute lavorazioni del terreno sono state connesse con alcuni effetti negativi sulle proprietà del suolo e con i relativi servizi ecosistemici. Per questo, lo studio di pratiche agronomiche più sostenibili rappresenta una sfida per l’intera comunità scientifica. Tra le tecniche agronomiche sostenibili, l’agricoltura conservativa (AC) è una pratica ampiamente diffusa che è basata su tre principi cardine: 1) minimo disturbo del suolo, 2) copertura permanente del terreo e 3) diversificazione delle colture. AC è spesso associata a numerose funzioni del suolo quali l’aumento della biodiversità, dello stock di carbonio organico e della stabilità degli aggregati e la riduzione del runoff, dell’erosione, delle lisciviazioni di P e delle emissioni di anidride carbonica. Nonostante ciò, recentemente AC non è sempre considerata come una soluzione vincente per la mitigazione del clima e per il miglioramento dell’agroecosistema in quanto l’assenza delle lavorazioni del terreno possono influenzare negativamente lo sviluppo radicale mediante un aumento della densità e della resistenza del suolo e mediante una diminuzione della porosità e degli scambi gassosi. Per di più, i benefici delle pratiche conservative sono riconosciuti essere strettamente legati al tipo di clima e suolo. In quest’ottica di risultati contrastanti, maggiori studi sono necessari per studiare e ottimizzare le potenzialità di pratiche agronomiche più sostenibili. Per questi motivi, in questa tesi, è stata condotta una prova di campo comprendente quattro aziende agricole della bassa pianura Veneta caratterizzate da suoli limosi nei quali le pratiche conservative (non lavorazione, cover-crop e ritenzione dei residui) sono state adottate e confrontate con quelle tradizionali. Il primo obiettivo di questa tesi è stato quello di valutare gli effetti di AC sul ciclo del C. In particolare è stata valutata l’evoluzione del carbonio organico del suolo (COS) sia in termini quantitativi che qualitativi durante un periodo di transizione di tre anni. Lo stock di COS è stato quantificato mediante l’applicazione della massa equivalente fino a 50 cm di profondità mentre l’effetto delle diverse componenti del trattamento conservativo è stato studiato considerando le biomasse delle colture, delle cover-crop e degli apparati radicali e il tipo di lavorazione come fattori separati. La qualità del COS è stata invece caratterizzata analizzando il carbonio umico, le sue frazioni in peso e la biomassa microbica. Questo studio ha mostrato come dopo un breve periodo di applicazione di tali pratiche, lo stock di COS nel suolo non sia aumentato mostrando piuttosto una diversa ripartizione lungo il profilo. La qualità del carbonio organico ha invece beneficiato delle pratiche conservative con la produzione di sostanze umiche più policondensate. Il secondo obiettivo ha riguardato lo studio dell’influenza di AC sugli scambi gassosi del suolo mediante l’analisi della permeabilità all’aria, della diffusione, della air-filled porosity e mediante la derivazione di indici di struttura su 144 campioni indisturbati di suolo di 100 cm3. Le analisi hanno evidenziato le scarse proprietà di trasmissione dei suoli limosi indipendentemente dalla pratica agronomica adottata che hanno portato al raggiungimento di valori critici sia per l’aerazione del terreno che per le attività microbiche aerobiche. Il terzo obiettivo si è focalizzato sulla caratterizzazione dell’evoluzione della struttura del suolo dopo cinque anni dall’adozione delle pratiche di AC. La porosità del suolo è stata analizzata sia mediante l’utilizzo di microtomografie a raggi-x che di porosimetrie a intrusione di mercurio. La porosità totale, la distribuzione dei pori (dalla macro- alla micro-scala) e l’architettura dei pori sono state quantificate su 96 campioni indisturbati raccolti nelle quattro aziende sperimentali. I risultati hanno mostrato come i suoli limosi del Veneto siano “microstrutturati” in quanto la maggior parte della porosità ricade nel range 0.0074-30 μm e come le pratiche conservative abbiano positivamente influenzato la ultramicroporosità (0.1-5 μm) che è strettamente legata alla protezione della sostanza organica. Concludendo, come evidenziato dallo scarso effetto sul sequestro del C, sugli scambi gassosi e sulla struttura del terreno, i suoli limosi della bassa pianura Veneta hanno mostrato una lenta reazione alle pratiche conservative. Lo scarso contenuto di COS non complessato disponibile all’interazione con le particelle fini del terreno ha ostacolato la formazione di una struttura stabile portando al compattamento del suolo. Nonostante ciò, le pratiche conservative hanno però positivamente influenzato la qualità del C e la ultramicroporosità suggerendo che un ciclo virtuoso tra sostanza organica e struttura del suolo è stato inizializzato. Un periodo di transizione di più lunga durata sembra essere indispensabile per il raggiungimento di un nuovo equilibrio in sistemi conservativi e più studi sui meccanismi che regolano la struttura in suoli limosi risultano inoltre necessari.

碩士
國立高雄海洋科技大學
水產食品科學研究所
100
This study, to determine the hygienic quality of 3% brine salted mackerel fillet packed with polyethylene (PE) or vacuum package and stored at various temperatures, showed that the vacuum package samples had more hygienic quality than PE package samples at the same storage temperature. The highest hygienic quality of low salted mackerel samples was observed at low temperature of -20 ℃, followed by storage at 4 ℃, 25 ℃ storage worst. To improve the processing of low salted mackerel and combination with Japanese method “overnight dry”, fresh mackerel fillets were salted with 0, 3.0, 6.0, 9.0, or 15.0% NaCl brine for 90 min and cold-air dried for 18℃, 23℃ and 28℃ at 12 or 18 drying time. The levels of aerobic plate count (APC) and total volatile basic nitrogen (TVBN) in fillet samples with 18℃ cold-air drying were the lowest, followed by 28℃ samples, and the highest levels at 23℃ samples in the same brine concentration. The levels of APC and TVBN of the salted mackerel fillets decreased with increased brine concentrations in the same drying temperature. Moreover, salted mackerel fillets produced by the cold-air drying at 12 hr had better hygienic quality than others produced by 18 hr. In conclusion, the samples produced by 9% brine concentration and cold-air drying at 18℃ for 12 hr had better hygienic quality and sensory test.

碩士
國立高雄海洋科技大學
水產食品科學研究所
100
An incident of foodborne poisoning due to consumption of fish fillets occurred in January, 2009, Kaohsiung city. The suspected fish samples contained 377 ppm of histamine. Moreover, the fish species of suspected samples were identified as mahi-mahi (Coryphaena hippurus) by polymerase chain reaction (PCR) direct sequence analysis. The objectives of this study were to investigate the hygienic quality and potential hazard of histamine in the mahi-mahi fillets and dried mahi-mahi products. Fifty-nine samples collected from retail market and the fishing village stores in Taiwan, including 42 mahi-mahi fillets and 17 dried mahi-mahi products, were tested to determine the occurrence of histamine and histamine-forming bacteria. The results showed that mahi-mahi fillets and dried mahi-mahi products had average levels of pH for 6.0 and 6.01, salt content for 0.22 and 2.92%, water content for 77.6 and 24.9% , water activity for 0.98 and 0.69, total volatile basic nitrogen for 13.7 and 39.6 mg/100 g, aerobic plate count for 4.7 and 5.9 log CFU/g, total coliform for 144.9 and 1098.5 MPN/g, and Escherichia coli for 1.8 and 162.9 MPN/g, respectively. The average biogenic amines levels in mahi-mahi fillets were below 1.0 mg/100g. In dried samples, only one sample had histamine content of 68.15 mg/100 g, which was greater than the 50 mg/100 g hazard level suggested by the U.S. Food and Drug Administration (US FDA). In addition, eight histamine-producing bacteria capable of producing 12.6 to 561.7 ppm histamine were isolated from mahi-mahi fillets and dried mahi-mahi products. To elucidate the histamine-related quality in mahi-mahi after being contaminated by Raoultella ornithinolytica Lc22, which was inoculated to mahi-mahi flesh and stored at various temperatures. The bacterial population rapidly increased at temperature above 15℃ and reached the highest bacterial count at 37℃. In addition, mahi-mahi flesh stored at 25℃ and 37℃ for 12 h and stored at 15℃ for 48 h, formed histamine levels which was greater than the hazard level (50 mg/100 g) set by the US FDA. However, the growth of histamine-forming bacteria and histamine production were inhibited at 4℃. Therefore, the results suggested that mahi-mahi should promptly be stored at below 4℃ to prevent the risk of histamine poisoning.

碩士
國立臺灣海洋大學
食品科學系
102
Temperature control is important for perishable products with short shelf life. Time temperature indicators (TTIs) are used as cost-effective devices to monitor the effect of temperature history on food quality. This study aims to develop a microbial TTI prototype to monitor grouper fillets quality change by using both total aerobic plate count and volatile basic nitrogen as quality indicators and evaluate the applicability of the TTIs as shelf life monitors　under real life conditions. Our design system considers following factors: selection of specific spoilage organism, selection of chemical chromatic indicators and selection of inoculum level of bacteria.　Results indicated Lactobacillus sakei is the major spoilage bacteria for vaccum package chilled grouper fillets. Chlorophenol red at 0.1 mg/ml is used as chemical indicator. 3 log cfu/ml is the inoculum level. Under such condition, the system successfully shows the color change occurs when ΔE is 20 and pH is 5.8. The activation energy of the designed TTI is 116.8 kJ/mol, which is close to the spoilage of grouper fillets sample, indicatedly volatile basic nitrogen. In addition, quality of grouper fillets are divided into three grades according to color changes of TTI. Overall, the findings offer a novel view of developing TTIs when using multiple quality indicators for seafood. Moreover, our results suggest that it is necessary to develop such TTIs since more than one quality indicator is important for an effective quality assurance system for seafood.

碩士
國立臺灣海洋大學
食品科學系
105
Neutral electrolyzed water can be divided slightly acidic electrolyzed water and slightly basic electrolyzed water because of its pH value, oxidation reduction potentials and available chlorine concentration. It is a safe and eco-friendly chlorine and chlorine derivative disinfectants. The aim of this study was to investigate the effects of slightly acidic and slightly basic electrolyzed water as the leaching water to improve the physicochemical properties of tilapia surimi and fillets. The bacteriostatic effect of the fillet was inoculated E. coli by treatment with 200 ppm slightly acidic electrolyzed water, 200 ppm slightly basic electrolyzed water, 200 ppm sodium hypochlorite aqueous solution and distilled water. The bacteriostatic effect of ACC 200 ppm slightly acidic electrolyzed water was better than others. The L value and pH of the meat increased as the washing cycles increased. After storage at 4 ± 1oC, the pH of the surimi showed an increasing trend, the control group of the volatile basic nitrogen will higher than other treatment group, initially. On the other sides, the value of volatile basic nitrogen in higher ACC concentration group was lower, while the value at the end of the storage periods was not exceed the standard for the tolerance. The aerobic plant counts of control group exceed the limit for the tolerance in the refrigerated food (3 x 106 CFU/g) during the storage periods. The L value, a value and b value of the surimi which treating by 200 ppm slightly acidic electrolyzed water’s group was higher than other groups. The L value, a value and b value of the surimi decreased as the storage times increased. As mentioned above, electrolyzed water treatment on tilapia surimi and fillets can reach the function of preservation effectively. The effect of inhibition E. coli of 200 ppm ACC slightly acidic electrolyzed water group was better than others.

The overall aim of my research was on one side, to investigate the possibility of using rapid and nondestructive methods for the determination of fish fillets quality and their classification, on the other side, to find out the stunning/slaughtering method able to guarantee a minimal or to completely avoid stress condition at the moment immediately prior of the slaughtering process, by assessing the effects on fillets quality by conventional and innovative methods, from two different farmed species [Atlantic salmon (Salmo salar L.) and rainbow trout (Onchorynchus mykiss)]. Percussion, asphyxia in the air, electroshock and asphyxia by carbon monoxide (CO) were tested; behaviour (on Atlantic salmon), stress indicators, shelf-life evolution during cold storage (raw fillets) and sensory analysis (cooked fillets) have been investigated, depending on stunning/slaughtering method and, in the case of rainbow trout, also on water rearing temperature.

Fish is a good source of fat, proteins, vitamins and minerals. It is the major contributor of long-chain omega-3 polyunsaturated fatty acids which are known to have a benefic effect on reducing the incidence of cardiovascular diseases. The world production of farmed fish has raised in the last decades as a consequence of the overexploitation of fishery resources and the wild stocks depletion. Aquaculture is making an important contribution to the demand of seafood and the sector continues to diversify, to use new species and to modify its system and practices towards safe and quality products. In Italy a considerable part of fish is sold fresh and intended for domestic consumption after cooking. Heat treatments such as smoking and parboiling are among the most spread processes applied by fish industry. The effect of cooking on seafood nutritional and organoleptic quality has been described by several researches focusing on both the changes of textural and colorimetric attributes and the retention of nutrients. Heat treatment generally induces structural changes of the muscle involving protein denaturation and gelatinization. Lipid and protein can be also oxidized by heat resulting in losses of nutritional value and formation of volatile molecules responsible for the aromatic profile. Depending on many intrinsic and extrinsic factors, including species, environmental and rearing conditions, storage time after death and type of heat treatment applied, farmed fish qualitative attributes can be subject to changes. The overall aim of this study was to assess the effects induced by cooking on quality of fillets from two different farmed species [meagre (Argyrosomus regius) and rainbow trout (Onchorynchus mykiss)] with reference to changes in physical parameters and nutritional profile. Cooking by boiling was tested and the variation of quality of both raw and cooked fillet depending on species, genetic strain (in rainbow trout), season, rearing system (land-based tank or off-shore cages, in meagre), farming conditions (in rainbow trou) and short-time chilling storage (in meagre) was studied. Specie-specific differences in fillet physico-chemical traits influenced raw flesh quality and the response to cooking. In meagre, which was an emerging species in Italian aquaculture, sampling times differences in macronutrients were nullified by cooking. Boiling method induced loss of some macronutrients, mainly lipids and some fatty acids, but changes detected did not compromise the valuable nutritional traits of this particularly lean species. Morpho-biometric traits of fish and colour, texture, macronutrients, fatty acids and minerals content of raw fillet were affected by rearing system, as a consequence of the diversified environmental parameters and conditions. Short time chilling did not affect nutritional profile and minimal changes, mostly involving colour and texture, were detected. In rainbow trout, which is the major farmed fish species in Italy, cooking by boiling modified physico-chemical profile in a different extent depending on the strain. Differences in some textural properties were nullified by cooking and specific farming conditions resulted to affect fillet quality in a different extent according to the strain.

碩士
國立臺灣師範大學
翻譯研究所
102
The use of fillers is quite common in daily conversation, but students studying interpreting have always been advised not to use fillers in interpretation. The quality of interpretation encompasses a wide range of aspects, but seldom do previous studies look into the influence of fillers on the quality of interpretation. This study intends to find that whether the use of fillers in interpreting influences users’ evaluation of interpretation quality. In this study, subjects were asked to evaluate four paragraphs of English to Chinese consecutive interpretation and give their reasons for the evaluation and preferences. The study shows that most subjects prefer the interpreting rendition without fillers and believe that the ones with fillers have lower quality because the rendition is more hesitant, disfluent, and the language used is more informal. In addition, the study also shows that subjects are more sensitive to hesitation fillers or filled pauses, including uh, na, e, ne, and seem not to be disturbed by placeholders such as ji ben shang, suo wei de, shi shi shang.

The purpose of aquaculture is to contribute to feed an increasing world population and to become more sustainable. Consequently, the aquafeed sector must adapt to supply more feed with less expensive and more eco-friendly ingredients. Insects have been studied as one of the promising and innovative protein sources. Evidence showed that their production leads to a circular bioeconomy, and generates positive societal externalities. Moreover, insects are considered fairly nutritious as aquafeed ingredients. Administering a new diet to fish rest on the assumption that animal welfare and final eating quality are preserved. The present thesis analyses the effects of feeding the Salmonidae Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss) with diets containing the larvae of Hermetia illucens, belonging to the Diptera order. The ultimate goal of the present research is to provide a meaningful insight into the decision making process for feeding and farming in order to optimise the overall production process. To fulfil this ambition, three topics were taken into consideration: - gut microbiota, for its countless functions and widespread impacts that it can have on the hosts; - lipid metabolism, for better understanding the laws behind the lipid constitution in the final product; - final product quality, specifically addressing its fatty acid composition, for the importance of fish fatty acids in human nutrition. The results on gut microbiota of either A. salmon or rainbow trout indicated that microbiota composition is modulated by dietary insect and that it differs depending on sample origin (mucosa or digesta). In addition to changes in composition, microbiota of fish fed diets containing insects was also marked by higher alpha- and beta-diversity. Additionally, mucosa samples tended to show lower alpha-biodiversity in comparison to digesta samples, fact that could be explained by positing that mucosa exercises an active selection. The examinations on lipid metabolism were performed on rainbow trout by calculating the indices of fatty acid metabolism and the ratio of products:precursors in liver and fillet, as well as by qPCR gene expression of pyloric caeca, mid intestine and liver. The three approaches agreed on the fact that lipid metabolism was affected by the diets containing the insect. Specifically, pyloric caeca elovl2 relative expression seemed to show an increased trend when rainbow trout were fed diets containing the insect. Also pyloric caeca and mid intestine fads2 expression seemed to increase following the increasing dietary insect. Minor effects on protein, fatty acid composition and fillet quality were noticed. Fillet fatty acid profile of A. salmon and rainbow trout fed diets containing the insect partly resembled the dietary fatty acid profile, commonly by showing an increase in saturated fatty acids. The cardioprotective fatty acids, namely polyunsaturated of the n-3 series, were successfully retrieved in fish fillets in satisfying amounts, not reflecting the dietary content. In addition, consumers appreciated steamed A. salmon fillets irrespective of the dietary treatment, though small weaknesses related to color intensity and textural attributes were raised in the fillets of the insect group. All things considered, diets containing insect guaranteed a nutritious and appreciated food. To conclude, as some bacteria may protect fish from pathogens as well as enhance physiological functions, it is highly desirable to delve into the effects that bacterial communities have on fish biology. Likewise, an interaction of microbiota with lipid metabolism cannot be excluded. H. illucens larvae used as dietary source for A. salmon and rainbow trout modulated lipid metabolism, but the final eating quality of fillets was highly preserved. It seems probable that the modulation of other oily ingredients may play a role in generating such an outcome, and further studies would be necessary to unravel the underlying dynamics. Additionally, tailoring H. illucens larvae by rearing them on a substrate from marine origin could help improve the final result.

Thesis (DTech. degree in Environmental management.)-Tshwane University of Technology, 2008.
Aims to determine the presence and levels of common polybrominated diphenyl ethers primarily in landfill leachates, but as well as sediment and groundwater (boreholes / wells around the landfill) from selected landfill sites in order to provide baseline data required to protect water resources against such chemicals.

碩士
國立高雄應用科技大學
工業工程與管理系碩士在職專班
104
This study examined the effect of the process parameters of magnesia filling in a tubular heating element on the filling quality under the application of the Taguchi quality engineering methods. Taguchi orthogonal arrays were used in the experimental design, which was aimed at determining the effect of the insulation powder amounts, oscillation, ascensional velocity, oscillating frequency, oscillating machine height, and the distance between oscillating plates on the filling quality, as well as at inspecting the elongation of a contracted tubular heater. The results indicated that the use of improved parameters can increase the heater’s elongation and reduce the difference and defect rate of magnesia powder filling.

With increasing population comes the concern for waste disposal. The absence of sanitary disposal methods has left most city residents with open landfills as their only source of waste disposal. The resulting leachate formed from the decomposition of these waste materials is highly polluting and finds its way to the underground water supply. The study investigated the effects of open landfill sites on the underground water quality by examining the physical and chemical properties of underground water in hand-dug wells around the Solous landfill sites in Igando, Alimosho Local Government Area of Lagos State. Solous landfill is the second largest landfill by landmass and volume of waste in Lagos State. Systematic random sampling was used for data gathering. Eighteen hand-dug wells were sampled at increasing distances from the landfill site. Physical, chemical and microbiological parameters were analysed at the Lagos State Environmental Protection Agency (LASEPA). Soil samples were also taken from both the A (0 – 30cm) and B (30 – 60cm) horizons of the water sampling points to determine the soil texture (silt, clay and loamy composition) and to show the impact of soil texture on ground water quality within the sampled area. The level of contamination of groundwater was also determined using the Contamination Index method. The results showed high degree of conformance with W.H.O standard with respect to the microbiological properties of the sampled groundwater. However, coliform tests indicated the potential presence of pathogens. Of the seven (7) physical parameters tested, conductivity was higher in one sample. The study of chemical properties from the eighteen wells showed five (5) parameters (dissolved oxygen, total alkalinity, iron, lead, nitrates and copper) above W.H.O limits in some samples. The water may therefore not be safe for human consumption and there is a serious need to monitor the groundwater quality in the area. The level of contamination of groundwater was also determined using the Contamination Index method. Areas of high and medium contamination were discovered. There was no area with low contamination level in the area sampled. Contamination levels were mapped to show the exact levels of contamination in the study area. The results of the soil analysis showed that the study area had soil that was mostly sandy in nature which may suggest an increase in parameters over time with significant health implications for the people who depend on surrounding wells for domestic use. The study also showed no significant variation in water quality with increasing distance from the dump site. Findings also indicated that the water around Solous 1 was of better quality for domestic use than groundwater around Solous 2 and 3 due to temporal reduction of contaminant concentration. There is therefore a need for adequate and proper planning, design and construction, and strategic management disposal of waste, as well as the implementation of a better sustainable environmental sanitation practice.
Environmental Sciences
M. Sc. (Environmental Science)

Landfills have served as the major sites for waste disposal in both developed and developing countries. Upon closure of a landfill site, the surface could be converted to a golf course, recreation park, playground, animal refuge, tennis court and industrial site. Even when closed, landfills still have the potential to contaminate the surrounding environment as a result of the migration of leachate from decomposing waste contained in the site. This study focused on assessing the impacts of a closed landfill on soils and plants at Lumberstewart closed landfill site in Bulawayo, Zimbabwe. Soil samples were collected at three different depths (0-30 cm, 30 - 60 cm and 60-90 cm) at the landfill and a control site. The soil samples were analysed for their texture, pH, electrical conductivity, organic matter content, cation exchange capacity and concentrations of Cd, Cu, Cr, Fe, Ni and Zn. Samples of jimson weed and pigweed growing at the closed landfill and the control site were collected from the same sites where soil samples were collected, and the concentrations of the same set of heavy metals in these weeds determined. Soil samples were digested using EPA method 3050B: Acid Digestion of Sediments, Sludge and soils whereas nitric acid and hydrogen peroxide was used for digestion of plant samples. Both plant and soil digests were analyzed for heavy metals concentrations using Flame Atomic Absorption Spectrometry (AAS). Soils from the landfill as well as the control site had a high content of sand with soil pH values which were alkaline. The electrical conductivity values of the soil samples were relatively low ranging from 0.39 to 1.67 dS/m, indicating low levels of salts in soils at the landfill. The concentrations of heavy metals at the closed landfill site were higher than the control site. Heavy metals concentrations in soils at the closed landfill followed the order Fe>Zn>Cu>Cr>Ni>Cd. Results indicated that Fe was exceptionally higher than the other metals with concentration values averaging 45690±17255 mg/kg. Cadmium on the other hand had the least concentration with values of 0.01±0.00 mg/kg. Values of Enrichment Factors of heavy metals around the soil at different depths indicated that the enrichment of heavy metals increased with depth at the landfill up to 30-60 cm after which a decrease was observed. Values for heavy metal Contamination Factor of soils around the landfill ranged from low concentration (CF<1) to very high concentration (CF>6). The Pollution Load Index (PLI) values for the soil at the Lumberstewart landfill indicated that all sites were polluted (PLI>1). Site 6 had significantly higher mean concentration of heavy metals in soils at the landfill whereas site 11 had the least. The concentrations of Cd and Ni in soils at the landfill were below permissible limits of South African National Norms and Standards (NNS) as prescribed by NEMA (2008) in South Africa whereas Cr, Cu and Zn in soils were above the NNS permissible limits. Heavy metal concentrations in soils at the landfill were above World Health (WHO) permissible limits except for Cd which was equal (0.01 mg/kg) to the permissible values of Cd in the soils at sites 5, 8, 9, 10, 11 and 12. Mean concentrations of heavy metals in jimson weed and pigweed were in the order Fe>Zn>Cu>Cr>Ni>Cd. The concentrations of Cd, Cr, Cu, Fe and Zn in both plants from all sites at the landfill were significantly higher than the control site. Heavy metal transfer coefficient for both plants indicated that heavy metal uptake was more species dependent than soil heavy metal concentration dependent. The results from this research indicate that though the Lumberstewart Landfill has been closed, it is still affecting the soils in the vicinity of the landfill. Plants and water around the Lumberstewart closed landfill could be at risk from heavy metal contamination. High concentrations of heavy metals observed in the soil could present a health risk to communities should they decide to use the landfill site for arable purposes.
Environmental Sciences
M. Sc. (Environmental Science)