Auswahl der wissenschaftlichen Literatur zum Thema „Seed Science and Technology“

Cranberry seed oil is a fine quality oil which can be marketed for its many beneficial functions to human health due to the presence of a unique combination of omega- 3, 6 and 9 fatty acids and the high concentration of antioxidants. Although there is no available clear data about the oil percentage of cranberry seeds in literature, an experiment was done to analyze the oil yields obtained through different processes such as heat reflux, microwave and ultrasound, both quantitatively and qualitatively. During preliminary experiments, better oil yields were obtained with ground seeds (10.11 ± 0.2%) in comparison with unground seeds (8.17 ± 0.3%) , and hence the seeds were made into a fine powder using a blender and the fine powders were separated by sieve (1mm). Hexane (10.2 ± 0.2%) was also found to be more efficient in oil extraction than Hexane: Ethanol (7:3) (6.45 ± 0.1%). The oil extraction process was based on four major operating factors namely the sample/solvent ratio, temperature, time and applied power for the heat reflux, microwave and ultrasound extraction. The results showed that the oil yield increased with an increase in sample/solvent ratio at 10g/100ml of hexane, temperature of 70⁰C in heat reflux which provided an oil yield about 11.19 ± 0.1% while in the case of microwave, best conditions were for a sample/solvent ratio of 5g/30ml of hexane, power at 125W, which gave an oil yield of 24.15 ± 0.3% maintaining the temperature at 66⁰C. In comparison, with ultrasound extraction at a sample/ solvent ratio of 5g/30ml of hexane, and a power at 150W, the oil yield was 32.35 ± 0.3%. The best yield results obtained for the tested methods for extracting oil from seeds were found and compared as: Heat reflux < Microwave <Ultrasound. The advantage of ultrasound was a relatively high yield over other methods with a short process time and lower process heat from the applied power. Analysis of quality in oil particularly the concentration of α - tocopherol was estimated by spectrophotometry at 520 nm and results found that α - tocopherol concentration was greatly affected by temperature at 70⁰C in case of heat reflux which retained around 0.266 ± 0.02 µg while in the case of microwave at power 125W and ratio 5g/30ml of hexane the tocopherol retained was around 0.346 ± 0.007 µg whereas in ultrasound the tocopherol was retained upto 0.428 ± 0.01 µg on applying power at 100W. The solvent extraction with hexane coupled with microwave or ultrasound energy released a greater amount of α - tocopherol from the plant matrix than for cold pressed method. For conventional cranberry seed oil extraction the cold pressed method was a better option than heat-reflux method in terms of oil quality, otherwise newer techniques such as MAE and UAE are highly recommended both in terms of increased oil yields and increased tocopherol content.<br>L'huile de graines de canneberges est une huile de qualité qui peut être mise en marché pour ses propriétés fonctionnelles "santé" issues de sa composition particulière en acides gras oméga 3, 6 et 9 et de sa forte concentration en antioxydants. Il existe peu ou pas d'information sur la teneur en huile de la graine de canneberge, cependant l'industrie alimentaire s'intéresse à l'extraction de cette huile, qu'elle effectue présentement par pressage à froid, malgré un faible rendement. Afin de palier à ce problème, une étude a débuté afin d'analyser les rendements en huile obtenus par différents procédés d'extraction dont l'ébullition à reflux, les microondes et les ultrasons. L'ébullition à reflux améliore l'extraction en améliorant la diffusion du solvant par la chaleur, tandis que dans le cas des microondes et des ultrasons, c'est plutôt la particularité des ondes qui influencent l'extraction. Les objectifs de cette recherche ont donc visé à obtenir de bons rendements en huile avec une forte teneur en α - tocophérol. Lors des essais préliminaires, de meilleurs rendements ont été obtenus avec des graines moulues (10.11 ± 0.2%) en comparaison avec des graines non moulues (8.17 ± 0.3%), ainsi tous les essais d'extraction ont par la suite été faits avec des graines finement moulues et tamisées (1mm). L'hexane (10.2 ± 0.2%) s' est avéré plus efficace pour l'extraction qu'un mélange d'hexane: éthanol (7:3) (6.45 ± 0.1%). L'étude de l'extraction de l'huile s'est concentrée sur quatre facteurs opérationnels soit le ratio d'échantillon/solvant, la température, le temps et la puissance appliquée pour l'ébullition à reflux, et l'extraction microonde et par ultrasons. Nos résultats ont démontré une augmentation du rendement en huile avec une augmentation du ratio échantillon/solvant à 10g/100 ml d'hexane, à une température de 70°C pour l' ébullition à reflux avec un rendement de 11.19 ± 0.1% tandis qu'avec l'extraction microonde, les meilleures conditions furent pour un ratio d'échantillon/solvant de 5g/30ml d'hexane, et une puissance de 125W, donnant une rendement en huile de 24.15 ± 0.3% à une température de 66⁰C. En comparaison, l'extraction ultrason, pour un ratio d'échantillon/solvant de 5g/30ml d'hexane, à une intensité de 150W, le rendement en huile a été de 32.35 ± 0.3%. Ainsi, les meilleurs résultats en terme de rendement en huile pour les différentes méthodes d'extraction sont classés comme suit: Ébullition par reflux < Microonde < Ultrason. L'avantage de l'extraction par ultrasons fut son haut rendement en huile, pour un procédé rapide, à température peu élevée. Le rendement maximal en huile a été obtenu par l'extraction ultrason avec 1.61 g. L'analyse de la qualité de l'huile, en particulier la teneur en α - tocophérol a été effectuée par spectrophotométrie à 520 nm et les résultats ont démontrés que la teneur en α - tocophérol était grandement affectée par la température, à 70⁰C dans le cas de l'ébullition par reflux avec 0.266 ± 0.02 µg, tandis qu'avec l'extraction microonde à la puissance de 125W au ratio de 5g/30ml d'hexane, la teneur en tocophérol était de 0.346 ± 0.007 µg, tandis que pour les ultrasons, la teneur en tocophérol était de 0.428 ± 0.01 µg pour une puissance de 100W. L'extraction par solvant, jumelée avec les microondes ou les ultrasons, libère une plus grande concentration en α - tocophérol des cellules de la plante en comparaison avec la pression à froid. En conclusion, l'extraction par pression à froid obtient une huile de meilleure qualité que l'huile obtenue par ébullition par reflux, tandis que l'extraction par microondes et par ultrasons est fortement recommandée pour un meilleur rendement en huile et une plus haute teneur en tocophérol.

<p> This research aims to provide a more complete understanding of almond seed coats, including microscopic development and structure, the relationship of measurable properties to surface area, and the kinetics of seed coat separation from the underlying almond kernel in response to a range of temperatures. </p><p> Immature almond samples of Nonpareil and Padre varieties were microscopically examined in the 16th-20th weeks after flowering (13 through 7 weeks prior to commercial harvest). The highly vacuolate and thin-walled diploid maternal tissues and triploid support tissue that sustain the embryo during development begin to rupture and compress down above a base monolayer of distinctly intact cells to form the mature seed coat. Over the course of blanching, no substantial swelling or dissolution of microscopic tissue layers was visible, however the junction between the base layer of the seed coat and the underlying almond cotyledon moved apart until they were no longer in contact with one another. </p><p> Surface areas of Nonpareil, Monterey, and Butte-Padre almonds were measured by manually peeling rehydrated nuts and analyzing images of their seed coats. Ninety-five percent of the 1,545 almonds measured in this study had surface areas between 515.96 mm²-942.24 mm². Surprisingly, individual dimensions (length, width, and thickness) did not increase with increasing surface area, nor they did scale in proportion to one other. An empirical model was created to predict surface area (r²=0.74), which depends on the almond variety, as well as length, width, and mass after rehydration. </p><p> The progression of blanching was examined by quantifying the degree of seed coat separation at dozens of intermediate time-points during the blanching process, using this empirical model. Experimental temperatures were 70&deg;C, 80&deg;C, 90&deg;C, and 100&deg;C; at each temperature, seed coat separation occurred in a sigmoidal logarithmic fashion. Rates of blanching were calculated using non-linear two-parametric regression. Rates of blanching at 100&deg;C and 90&deg;C were not significantly different, however, blanching rates decreased semi-logarithmically with decreasing blanching temperature between 70&deg;C and 90&deg;C. D-values representing 90% seed coat separation were calculated as 30 seconds at 100&deg;C, 35 seconds at 90&deg;C, 120 seconds at 80&deg;C, and 443 seconds at 70&deg;C. From these, a z value for decimal reduction times between 70&deg;C and 90&deg;C was calculated at 18.48C degrees. </p><p> The novel empirical model for surface area could be used to improve the accuracy of mass transfer and energetic transfer calculations in almond processing. Quantifying the rate of seed coat separation could be used to explore any aspect of almond physiology dependent on or resultant from seed coat integrity, such as germination, rehydration kinetics, processing damage, or blanching efficacy. It could also potentially be used to compare the relative blanching propensity of different almond varieties, as well as evaluating the impact on skin separation of various growing, harvesting, and processing conditions. D- and z values characterizing the almond blanching process may be useful in optimizing almond processing conditions to reduce the chances of accidental seed coat separation, or to more efficiently achieve it.</p>

Ecological restoration of rangelands using wild-collected seeds can be challenging due to low seed quality, inconvenient seed anatomy, and poor plant establishment. In North America, the half-shrub winterfat (Krascheninnikovia lanata) is a valuable protein-rich forage for wildlife and livestock. Seeds of this species are contained in one-seeded fruits enclosed in four fluffy, silky bracts. While the seeds can be removed from the bracts, it is not recommended as the bracts are thought to help protect the seed and aid in germination and seedling growth. However, bracts of winterfat make it difficult to incorporate this species within a seed mix because it prevents the seed from flowing through mechanized seeders. The anatomy of winterfat fruit also makes it difficult to treat this species with external seed coating materials that may aid in direct seeding efforts. We tested the use of a recently developed flash flaming technique in combination with seed coating to improve the flowability of winterfat fruits. Our results indicate that flash flaming can reduce the appendages on winterfat fruits, which decreased fruit volume by up to 46% without impacting seed germination. Flash flaming also makes it possible to incorporate a polymer seed coating to the exterior of winterfat fruits. We found that flash flaming combined with seed coating improved the flowability of winterfat fruits, as measured with standard laboratory tests, and by delivering fruits through a broadcast seeder and a rangeland drill. These results indicate that flash flaming plus seed coating provides a new technology that will allow for the treating and planting of winterfat on degraded rangelands.

Arid and semi-arid rangelands are important ecosystems that are consistently degraded through disturbances such as wildfires. After such disturbances, the invasion and dominance of annual grasses, like cheatgrass (Bromus tectorum L.), can lead to an overall loss of ecosystem productivity and an increase in fire frequency. To reduce weed dominance, native and introduced perennials species are typically be seeded in the fall. High mortality is seen from these seeded plant communities due to germinated seed being exposed to freezing, drought, fungal pathogens, and other biotic and abiotic stressors during winter months. We utilized wet-thermal accumulation models to first further validate the theory that germination from seeded plant populations occurs during periods of high environmental stress, and then to establish the practicality of abscisic acid seed coatings as a technology that could circumvent winter germination and mortality. In Chapter 1, we developed an excel workbook called Auto-Germ using Visual Basic for Applications, which allows users to estimate field germination timing based on wet-thermal accumulation models and field data. We then used Auto-Germ to model seed germination timing for 10 different species, across 6 years, and 10 Artemisia-steppe sites in the Great Basin of North America. We estimated that for the majority of the species analyzed, a mid to late-winter planting was required on average for the majority of the population to germinate in the spring. This planting time would be logistically difficult for many land managers, due to freezing and/or saturated soil conditions. In Chapter 2, we utilized wet-thermal accumulation models to evaluate the use of abscisic acid (ABA) to delay germination of Pseudoroegneria spicata (Pursh) Á. Löve (perennial native bunchgrass) across 4 years and 6 Artemisia-steppe sites. Germination models estimated that ABA seed treatments typically would delay germination of fall sown seed to late winter or early spring when conditions may be more favorable for plant establishment. Based on these results, we recommend both the use of wetthermal accumulation models as a tool in educating researchers and land managers in knowing when seeding practices should occur, and the further study of ABA seed coatings as a technology that may improve plant establishment of fall sown seeds.

<p>This thesis was based on a larger international comparative study called the ROSE (Relevance of Science Education) project. The study investigated the affective factors pupils perceive might be of relevance for the learning of science and technology using the ROSE survey questionnaire, and was aimed at providing data that might form part of an empirical basis for local adaptation of the science curriculum.</p>

Chickpea (Cicer arietinum L.) and oat (Avena sativa L.) seeds are important sources of protein ingredients with potential nutritional, functional and bioactive properties. Protein fractions were prepared from chickpea and oat using sequential extractions with distilled water (albumins), NaCl solution (globulins) and NaOH solution (glutelins), respectively. Molecular characteristics of individual protein fractions were investigated using polyacrylamide gel electrophoresis (Native- and SDS-PAGE, and 2-DGE) in combination with reversed-phase high performance liquid chromatography (RP-HPLC). Tryptic peptide sequences were identified using proteomic techniques including 1D trypsin in-gel digestion, liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) analysis and Mascot MS/MS ion search. Sequence similarity and potential bioactivity of proteins were examined using BLAST and BIOPEP analysis, respectively. Native-PAGE results showed chickpea and oat globulin fractions (C-Gb and O-Gb) contained proteins corresponding to legumin (11S) and avenalin (12S), respectively. SDS-PAGE revealed that chickpea albumin and globulin fractions (C-Ab and C-Gb) showed protein bands with MWs related to legumin (11S) and pea vicilin (7S) while chickpea glutelin fraction (C-Gt) showed protein bands with MWs related to rice glutelin; oat protein fractions (O-Ab, O-Gb and O-Gt) showed protein bands with MWs related to oat 12S globulin (avenalin). α- and β-subunits of globulin and glutelin fractions from chickpea and oat were identified with estimated MWs ranging from 31 to 45 kDa and from 21 to 31 kDa, respectively. In vitro chickpea albumin, globulin and glutelin hydrolysates showed DH of 22.8%, 28.6% and 28.8%, respectively; SDS-PAGE revealed that legumin α- and β-subunits from chickpea globulin fraction (C-Gb) were hydrolyzed. The identified tryptic peptides from chickpea and oat protein fractions showed sequence homology that corresponded to chickpea l<br>Les semences du pois chiche (Cicer arietinum L.) et de l'avoine (Avena sativa L.) sont d'importantes sources d'ingrédients protéiques dont les propriétés nutritionnelles, fonctionnelles et bioactives démontrent un grand potentiel. Les fractions protéiques ont été préparées à partir du pois chiche et de l'avoine par extraction séquentielle avec de l'eau distillée (albumine), une solution de NaCl (globuline) et une solution de NaOH (glutelines), respectivement. Les caractéristiques moléculaires des fractions de protéines individuelles ont été examinées par électrophorèse en gel de polyacrylamide (non dénaturante et SDS-PAGE, et 2-DGE) en combinaison avec la chromatographie en phase liquide à haute performance en phase inversée. Les séquences de peptides tryptiques ont été identifiées par des techniques protéomiques telles que la digestion de trypsine en gel unidimensionnelle, l'analyse chromatographique en phase liquide couplée à la spectrométrie de masse en tandem avec ionisation de type électrospray (LC-ESI-MS/MS), et la recherche d'ions MS/MS (Mascot). Les similarités séquentielles et la bioactivité potentielle des protéines ont été examinées sous analyse par BLAST et BIOPEP, respectivement. Les résultats de l'électrophorèse non dénaturante en gel de polyacrylamide démontrent que les fractions de globulines du pois chiche et d'avoine (C-Gb et O-Gb) contiennent des protéines correspondant aux légumines (11S) et avenaline (12S), respectivement. La SDS-PAGE révèle que les fractions d'albumine et de globuline de pois chiche (C-Ab et C-Gb) montrent des bandes protéiques ayant des poids moléculaires reliés à la légumine (11S) et le viciline de pois (7S) alors que la fraction de glutéline de pois chiche (C-Gt) montre des bandes protéiques avec des poids moléculaires reliés à la glutéline de riz; les fractions protéiques d'avoine (O-Ab, O-Gb et O-Gt) montrent de bandes protéiques avec des poids moléculaire

Questa tesi è la conclusione di un lavoro all’interno di I SEE (Inclusive STEM Education to Enhance the capacity to aspire and imagine future careers), un progetto europeo Erasmus+ coordinato dall’Università di Bologna e che coinvolge altri sei partner (http://iseeproject.eu). Il mio lavoro ha portato allo sviluppo di un’attività didattica intitolata “Applicazioni e implicazioni dei computer quantistici nella società” che è parte di un modulo I SEE sui computer quantistici. Progetto e attività mirano a contribuite a due dibattiti nella ricerca sull’educazione scientifica: quello sulla didattica STEM e sulla sua posizione in contesti di ricerca, istituzionali e didattici; quello sulla percezione del futuro da parte dei giovani in questo mondo in accelerazione. Il primo capitolo riguarda lo stato dell’arte del dibattito sulla didattica STEM, da un punto di vista sia di ricerca che istituzionale, come modo di affrontare temi chiave che riguardano il rapporto problematico tra scienza e società. Nel secondo capitolo, viene presentato il progetto I SEE e collocato all’interno della ricerca nella didattica STEM. È fornita una descrizione di come tale progetto contribuisce a promuovere lo sviluppo delle cosiddette future-scaffolding skills e a disegnare un approccio STEM integrato, con una descrizione dei moduli finlandese e italiano sulle tecnologie quantistiche. Il terzo capitolo include la descrizione dell’attività che ho contribuito a sviluppare. Essa è stata costruita per raggiungere diversi obiettivi tra cui guidare gli studenti di scuola secondaria a familiarizzare con la terminologia, le prospettive e i contenuti di documenti istituzionali come il Quantum Manifesto, e rendersi conto delle tante dimensioni coinvolte, riconoscendo dove e come le tecnologie quantistiche potranno essere d’impatto nella vita del singolo. Infine, si discutono i risultati dell’implementazione dell’attività avvenuta a Bologna nel febbraio 2019 con 25 studenti di scuola secondaria.

Although the history of Virtual Reality (VR) is only about half a century old, all kinds of technologies in the VR field are developing rapidly. VR is a computer generated simulation that replaces or augments the real world by various media. In a VR environment, participants have a perception of “presence”, which can be described by the sense of immersion and intuitive interaction. One of the major VR applications is in the field of sports, in which a life-like sports environment is simulated, and the body actions of players can be tracked and represented by using VR tracking and visualisation technology. In the entertainment field, exergaming that merges video game with physical exercise activities by employing tracking or even 3D display technology can be considered as a small scale VR. For the research presented in this thesis, a novel realistic real-time table tennis game combining immersive, interactive and competitive features is developed. The implemented system integrates the InterSense tracking system, SwissRanger 3D camera and a three-wall rear projection stereoscopic screen. The Intersense tracking system is based on ultrasonic and inertia sensing techniques which provide fast and accurate 6-DOF (i.e. six degrees of freedom) tracking information of four trackers. Two trackers are placed on the two players’ heads to provide the players’ viewing positions. The other two trackers are held by players as the racquets. The SwissRanger 3D camera is mounted on top of the screen to capture the player’s

Spotted knapweed (Centaurea stoebe L.) is a deeply taprooted perennial forb infesting millions of hectares of rangeland in western North America. Spotted knapweed forms large monocultures, which lowers plant diversity, reduces livestock and wildlife forage, and increases surface water runoff and sediment yield. It can produce 5,000-40,000 seeds m-2 year-1, and often produces new flowers after prescribed sheep grazing or mowing defoliates spotted knapweed plants during the bolting or flowering stage. Research has yet to determine if new flowers produced following spring/summer defoliation produce viable seeds by the end of the growing season. The purpose of this 2-year study was to determine the appropriate timing(s) or combination(s) of timings of defoliation on spotted knapweed to reduce viable seed production. Ten spotted knapweed plants, located on spotted knapweed-infested rangeland in west-central Montana, were hand-clipped for each of the following treatments: 1) 35-40% relative utilization of above-ground biomass when plants were in the bolting stage; 2) 100% of buds removed at late-bud/early-flowering stage; 3) 100% of flowers removed at full-flowering stage; 4) Treatment 1+Treatment 2; 5) Treatment 1+Treatment 3; 6) Treatment 2+Treatment 3; 7) Treatment 1+Treatment 2+Treatment 3; and 8) unclipped control. The number of buds/flowerheads per plant, number of seeds per plant, percent viability of seeds, and number of viable seeds per plant were determined when seeds were in the well-developed stage, but seedhead bracts were still tightly closed (mid-August through September). Clipping at any timing or combination of timings reduced the number of buds/flowerheads per plant (P < 0.01), number of seeds per plant (P < 0.01), percent viability of seeds (P < 0.01), and number of viable seeds per plant (P < 0.01) both years compared with the unclipped control. Clipping during the bolting stage reduced the number of viable seeds by nearly 90% compared with no clipping. Clipping during the late-bud/early-flower or full-flower stage reduced the number of viable seeds by nearly 100% compared with no clipping. Defoliation of spotted knapweed via prescribed sheep grazing or mowing in summer should effectively suppress viable seed production of spotted knapweed.