Academic literature on the topic 'Digesta markers'
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Journal articles on the topic "Digesta markers"
1
Ortigues, I., J. D. Oldham, T. Smith, M. B. de Courtenay, and J. W. Siviter. "A comparison between ytterbium acetate, ruthenium phenanthroline and indigestible acid detergent fibre in a double-marker system for intestinal flow measurements in steers." Journal of Agricultural Science 114, no. 1 (January 1990): 69–77. http://dx.doi.org/10.1017/s002185960007101x.
Full textAbstract:
SUMMARYThree double-marker systems were used in cannulated steers offered straw-based diets supplemented with barley, fishmeal or a combination of both, in an attempt to reduce the risks of misinterpreting biological results based on calculations of digesta flows using markers. Ruthenium phenanthroline (Ru-phe), ytterbium acetate (Yb-ac) and the indigestible acid detergent fibre fraction (IADF) were used as markers of the particulate phase of digesta in conjunction with Cr-EDTA as a liquid-phase marker to estimate duodenal and ileal digesta flows. The present paper presents the difficulties met in the application of marker techniques.The particulate marker used in a double-marker system for calculation of nutrient flow modified the degree of statistical significance observed for dietary treatment effects on digesta flow parameters.The data suggest that the type of diet used affects the behaviour of individual markers in different ways and could incur some bias in the results. It is hypothesized that the physical and chemical characteristics of digesta, in different dietary conditions, can be responsible for differential attachment of markers to particles of the solid phase. In such cases, the distinction made in the double-marker technique between particulate and liquid phases may not be sufficient to correct for lack of representativeness of digesta contents sampled from T-shaped cannulae.For the diets studied it was concluded that the interpretation of digestion parameters should be based on both Ru-phe and Yb-ac results.
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Faichney, GJ. "Application of the double-marker method for measuring digesta kinetics to rumen sampling in sheep following a dose of the markers or the end of their continuous infusion." Australian Journal of Agricultural Research 43, no. 2 (1992): 277. http://dx.doi.org/10.1071/ar9920277.
Full textAbstract:
Methods are described by which the double-marker method for measuring digesta kinetics may be applied to rumen samples taken from sheep maintained in steady-state conditions, while marker concentrations are declining after a single dose of the two markers, or cessation of their continuous infusion, or increasing in the pre-equilibrium phase of their unprimed continuous infusion. Also described are procedures for checking the consistency of analyses applied to digesta, fluid-phase and particle-phase samples and for physically reconstituting true digesta samples. Errors due to deviations of the markers from ideal behaviour are examined.
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Ahvenjärvi, Seppo, Aila Vanhatalo, Kevin J. Shingfield, and Pekka Huhtanen. "Determination of digesta flow entering the omasal canal of dairy cows using different marker systems." British Journal of Nutrition 90, no. 1 (July 2003): 41–52. http://dx.doi.org/10.1079/bjn2003876.
Full textAbstract:
Four studies were conducted to compare the effect of four indigestible markers (LiCoEDTA, Yb-acetate, Cr-mordanted straw and indigestible neutral-detergent fibre (INDF)) and three marker systems on the flow of digesta entering the omasal canal of lactating dairy cows. Samples of digesta aspirated from the omasal canal were pooled and separated using filtration and high-speed centrifugation into three fractions defined as the liquid phase, small particulate and large particulate matter. Co was primarily associated with the liquid phase, Yb was concentrated in small particulate matter, whilst Cr and INDF were associated with large particles. Digesta flow was calculated based on single markers or using the reconstitution system based on combinations of two (Co + Yb, Co + Cr and Co + INDF) or three markers (Co + Yb + Cr and Co + Yb + INDF). Use of single markers resulted in large differences between estimates of organic matter (OM) flow entering the omasal canal suggesting that samples were not representative of true digesta. Digesta appeared to consist of at least three phases that tended to separate during sampling. OM was concentrated in particulate matter, whilst the liquid phase consisted mainly of volatile fatty acids and inorganic matter. Yb was intimately associated with nitrogenous compounds, whereas Cr and INDF were concentrated in fibrous material. Current data indicated that marker systems based on Yb in combination with Cr or INDF are required for the accurate determination of OM, N and neutral-detergent fibre flow. In cases where the flow of water-soluble nutrients entering the omasal canal is also required, the marker system should also include Co.
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Scholljegerdes, Eric J. "347 Choosing an external marker for measuring intake and digestibility in ruminants." Journal of Animal Science 98, Supplement_4 (November 3, 2020): 79. http://dx.doi.org/10.1093/jas/skaa278.144.
Full textAbstract:
Abstract Proper nutrition is key to maintaining and improving animal productivity. Measuring intake and site and extent of digestion is essential for appropriate diet formulation. However, it is extremely difficult to accurately account for the dynamic nature of the ruminant digestive tract. External markers have long been used as a tool to measure digesta output, yet proper marker selection can be challenging. The aim of this review is to provide guidance in the selection of external markers in ruminant nutrition studies. External markers must satisfy certain requirements in order to be considered a valid marker. These requirements include, but are not limited to, being inert in the gastrointestinal tract, mixing with the digesta, and having high recovery rate in the feces. In addition, laboratory analysis needs to be easily reproducible within and amongst laboratories. Health hazards of the marker must also be kept in mind for the laboratory worker and the animal. There are a number of elements that have been utilized as external markers. Currently in the literature, chromic oxide (Cr2O3), long-chain alkanes (C32 to C36) and titanium dioxide (TiO2) are the most commonly used external markers. Each have been extensively evaluated and have their own positive and negative attributes. Results comparing fecal recoveries has been extensively reported in various diets fed to large and small ruminants. Of the three most widely utilized external markers, all have demonstrated adequate fecal recoveries, reasonable estimates of total duodenal and fecal digesta flows or output. Therefore, the selection of the appropriate marker comes down to the ease and accuracy at which analysis can be conducted, dosage rate, minimum dosage frequency, and safety to the user and animal.
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Sakaguchi, EI, Hiroshi Itoh, Senji Uchida, and Takao Horigome. "Comparison of fibre digestion and digesta retention time between rabbits, guinea-pigs, rats and hamsters." British Journal of Nutrition 58, no. 1 (July 1987): 149–58. http://dx.doi.org/10.1079/bjn19870078.
Full textAbstract:
1. Digestive efficiencies of fibre components and retention time of digesta in the whole gut and in the large intestine were measured in rabbits, guinea-pigs, hamsters and rats when given a lucerne (Medicago saliva)-containing diet.2. Co-EDTA and chromium-mordanted cell-wall constituents of Italian ryegrass (Lolium multiflorum L.) were used as liquid- and solid-phase markers respectively. Both markers were mixed with the experimental diet and given after digestion trials.3. Mean retention times of each marker were calculated from time-course changes in concentrations of the markers in faeces. The mean retention times of the markers in the large intestine were calculated from exponential slopes fitted to the time-course changes of faecal concentrations of the markers.4. The digestibilities of crude fibre, neutral-detergent fibre and acid-detergent fibre were highest in the guineapigs, followed by the hamsters, and lowest in the rabbits and rats.5. The mean retention times of Cr in the whole tract were longer in the larger animals and shortest in the hamsters. The mean retention times of Cr in the large intestine were longest in the guinea-pig followed by the hamsters and the rats. The rabbits had an extremely short retention time of Cr in the large intestine.6. These results suggest that the retention time of solid digesta in the large intestine can explain the difference in the digestive efficiencies of fibre components amongst non-ruminant small herbivores whereas retention of digesta in the whole gut is not related to the digestibility of fibre components.
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Holleman, D. F., and R. G. White. "Determination of digesta fill and passage rate from nonabsorbed particulate phase markers using the single dosing method." Canadian Journal of Zoology 67, no. 2 (February 1, 1989): 488–94. http://dx.doi.org/10.1139/z89-071.
Full textAbstract:
A method is given for analyzing particulate digestive marker data in terms of digesta fill, fecal output, and digesta passage times. The method applies the Stewart – Hamilton Principle to data obtained from a single marker dosing followed by feces sampling; it assumes steady-state conditions for the digesta, but makes no assumptions concerning compartmentalization of digesta. Data analyses are presented for an experiment with sheep in which a particle phase marker, cerium-141 chloride, was used. The estimate of fecal output obtained was 1.8 ± 2.2% (mean percent difference ± SE) greater than the actual fecal output; the in vivo estimate of total digesta fill was 3.3 ± 3.4% less than measured digesta fill. For comparison, the present data were also analyzed using two established compartment modeling approaches, namely a time-independent and a time-dependent two-compartment model. The only significant difference between the estimated parameters as obtained from the Stewart – Hamilton method and the compartmental models was a significantly shorter transit time as estimated by the time-dependent model.
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Brand, S. J., J. M. Lanyon, and C. J. Limpus. "Digesta composition and retention times in wild immature green turtles, Chelonia mydas: a preliminary investigation." Marine and Freshwater Research 50, no. 2 (1999): 145. http://dx.doi.org/10.1071/mf98033.
Full textAbstract:
Digesta retention time (DRT) of particulate matter (the calculated time for elimination of 50% of marker beads) and food intake levels were measured in three wild immature green turtles, Chelonia mydas, by using inert plastic markers. DRTs were long, ranging from 156 to 325 h (6.5–13.5 days).
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Siddons, R. C., J. Paradine, D. E. Beever, and P. R. Cornell. "Ytterbium acetate as a particulate-phase digesta-flow marker." British Journal of Nutrition 54, no. 2 (September 1985): 509–19. http://dx.doi.org/10.1079/bjn19850136.
Full textAbstract:
1. The ability of ytterbium acetabe (Yb acetate) to fulfil the requirements of a particulate-phase digesta-flow marker in a dual-phase marker system, and of the indigestible acid-detergent-fibre fraction of the feed (IADF) to act as a digesta flow marker, were examined using six mature wether sheep given a diet of dried grass (1 kg dry matter (DM)/d).2. CrEDTA was continuously infused (240 mg chromium/d) into the rumen of all sheep and Yb acetate was also continuously infused (100 mg Yb/d) into the rumen of three of the sheep. At this level of infusion the equilibrium concentration of Yb in rumen, duodenal and ileal digesta and in faeces could be reliably measured by atomic absorption spectrometry.3. Estimates of faecal DM excretion based on either Yb or IADF did not differ (P > 0.05) from that determined by total collection, whereas estimates based on Cr were significantly (P < 0.05) lower. Urinary excretion accounted for 3.1% of the infused Cr but no Yb was detected in urine. Estimates of ileal DM flow, assuming total marker recovery, were similar (P > 0.05) with all three markers, whereas the estimate of duodenal DM flow based on IADF was lower (P < 0.05) than the estimates based on either Cr or Yb.4. Compared with the infusion of Cr alone, the infusion of Cr and Yb had no effect (P > 0.05) on nutrient flows at the duodenum, ileum and in faeces nor on microbial degradative activity, volatile fatty acid production and N metabolism in the rumen.5. Polyester bag and in vitro studies showed that pre-labelling the dried grass with up to 285 mg Yb>g DM did not affect its susceptibility to microbial degradation.6. The Yb in rumen, duodenal and ileal digesta was predominantly (> 90%) associated with the particulate matter but was not uniformly distributed and its concentration increased as particle size decreased.7. The use of CrEDTA and Yb acetate as a dual-phase marker system proved more reliable in estimating ‘true’ duodenal flow than the use of the individual markers when the digesta sample was unrepresentative.
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Lanyon, JM, and H. Marsh. "Digesta Passage Times in the Dugong." Australian Journal of Zoology 43, no. 2 (1995): 119. http://dx.doi.org/10.1071/zo9950119.
Full textAbstract:
The retention times of particulate digesta were measured in two captive dugongs, Dugong dugon (Muller 1776) using inert plastic markers. The mouth-to-anus retention times (146-166 h) were similar to those of the West Indian manatee, and much longer than those of most other herbivorous mammals. This slow gut passage rate may be explained by the dugong's long digestive tract, the low fibre level of the diet and the low food intake. Like the manatee, the dugong appears to have a digestive strategy that is atypical of hindgut fermenters: low-fibre material is retained for extended periods within the long hindgut and almost completely digested.
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Nevel, C. van, and D. Demeyer. "Comparison of two solid-phase markers for measuring the flow of digesta components in the duodenum of sheep." Netherlands Journal of Agricultural Science 37, no. 3 (September 1, 1989): 197–203. http://dx.doi.org/10.18174/njas.v37i3.16631.
Full textAbstract:
The effect of defaunation and refaunation of the rumen of sheep on duodenal passage and rumen digestion was studied. A combination of chromic oxide and polyethylene glycol (PEG) mixed with concentrates was used to estimate intestinal flow. In addition a combination of PEG and Ru-phenanthroline continuously infused in the rumen was used. Differences in flow of duodenal digesta and digesta components, calculated with both marker systems, were rare and small, indicating that Cr2O3 was an adequate marker of the solid phase of the digesta for application of the double-marker method. (Abstract retrieved from CAB Abstracts by CABI’s permission)
Dissertations / Theses on the topic "Digesta markers"
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Herron, Fiona Michelle. "A study of digesta passage in rabbits and ringtail possums using markers and models." Thesis, The University of Sydney, 2002. http://hdl.handle.net/2123/483.
Full textAbstract:
The common ringtail possum (Pseudocheirus peregrinus), a member of the family Pseudocheiridae, is an arboreal folivorous marsupial that feeds predominantly on Eucalyptus foliage. Contrary to the expectation that small body size would inhibit utilisation of a diet containing such high levels of lignified fibre because of relatively low gut volume to body mass ratios and relatively high mass-specific metabolic rates and nutrient requirements (Hume 1999), the ringtail possum is able to survive solely on a diet of Eucalyptus foliage. The rabbit (Oryctolagus cuniculus) is a terrestrial herbivore and is a member of the family Leporidae that feeds predominantly on grasses. The rabbit was proposed as a digesta flow model for the ringtail possum since both are caecotrophic (periodically re-ingest caecal contents) and both are proposed to exhibit a colonic separation mechanism (CSM) where fluids and small, easily digested particles are preferentially returned to the caecum. The rabbit is of value for the modelling process since it is more accessible for experimental manipulation than the ringtail possum. This study investigated a proposal to use digesta passage through the gastrointestinal tract (GIT) of the rabbit as a model of digesta passage for the ringtail possum on the basis that both are caecotrophic caecum fermenters. A number of potential problems were identified with this proposal and investigation of these problems formed the basis for the research described in this thesis. Two main areas were identified as being potentially problematic: 1) fundamental flaws with the particulate markers used in digesta rate of passage studies; and 2) differences in animal behaviour and natural diet between the two subject species which suggested different digestive strategies and hence different patterns of digesta flow through the GIT. The proposed digesta passage markers were lanthanide metals (Dy, Tm, Eu and Yb) attached to either fibrous particles (1200 - 600�m) or formalin-fixed rumen bacteria (20 � 0.2�m). These markers were shown to not be of the assumed size classes and the extent of lanthanide metal binding differed between the four metals used. An effect due to method of dosing was also observed. The findings of marker inconsistencies caused major limitation to model development and further research is necessary to clarify these markers. The proposal to use digesta flow in the rabbit GIT as a model for digesta flow in the ringtail possum was shown to be idealistic due to the differences in anatomy and behaviour observed between the two herbivores. Laboratory observations, time series analysis and compartmental modelling confirmed the differences between the animals. This study showed: 1) the GIT of the rabbit was more complex both anatomically and functionally than that of the ringtail possum; 2) behaviour affecting digesta passage of the rabbit and ringtail were different and; 3) compartmental models confirmed the anatomical and behavioural findings. Digesta passage in the rabbit could not be modelled mathematically using data on digesta passage due to complexities of the system. In contrast, a basic model was constructed for digesta passage in the ringtail possum. On the basis of these findings, the research hypothesis "that digesta passage in rabbits is similar to that in ringtail possums" was rejected.
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Herron, Fiona Michelle. "A study of digesta passage in rabbits and ringtail possums using markers and models." University of Sydney. Biology, 2002. http://hdl.handle.net/2123/483.
Full textAbstract:
The common ringtail possum (Pseudocheirus peregrinus), a member of the family Pseudocheiridae, is an arboreal folivorous marsupial that feeds predominantly on Eucalyptus foliage. Contrary to the expectation that small body size would inhibit utilisation of a diet containing such high levels of lignified fibre because of relatively low gut volume to body mass ratios and relatively high mass-specific metabolic rates and nutrient requirements (Hume 1999), the ringtail possum is able to survive solely on a diet of Eucalyptus foliage. The rabbit (Oryctolagus cuniculus) is a terrestrial herbivore and is a member of the family Leporidae that feeds predominantly on grasses. The rabbit was proposed as a digesta flow model for the ringtail possum since both are caecotrophic (periodically re-ingest caecal contents) and both are proposed to exhibit a colonic separation mechanism (CSM) where fluids and small, easily digested particles are preferentially returned to the caecum. The rabbit is of value for the modelling process since it is more accessible for experimental manipulation than the ringtail possum. This study investigated a proposal to use digesta passage through the gastrointestinal tract (GIT) of the rabbit as a model of digesta passage for the ringtail possum on the basis that both are caecotrophic caecum fermenters. A number of potential problems were identified with this proposal and investigation of these problems formed the basis for the research described in this thesis. Two main areas were identified as being potentially problematic: 1) fundamental flaws with the particulate markers used in digesta rate of passage studies; and 2) differences in animal behaviour and natural diet between the two subject species which suggested different digestive strategies and hence different patterns of digesta flow through the GIT. The proposed digesta passage markers were lanthanide metals (Dy, Tm, Eu and Yb) attached to either fibrous particles (1200 - 600�m) or formalin-fixed rumen bacteria (20 � 0.2�m). These markers were shown to not be of the assumed size classes and the extent of lanthanide metal binding differed between the four metals used. An effect due to method of dosing was also observed. The findings of marker inconsistencies caused major limitation to model development and further research is necessary to clarify these markers. The proposal to use digesta flow in the rabbit GIT as a model for digesta flow in the ringtail possum was shown to be idealistic due to the differences in anatomy and behaviour observed between the two herbivores. Laboratory observations, time series analysis and compartmental modelling confirmed the differences between the animals. This study showed: 1) the GIT of the rabbit was more complex both anatomically and functionally than that of the ringtail possum; 2) behaviour affecting digesta passage of the rabbit and ringtail were different and; 3) compartmental models confirmed the anatomical and behavioural findings. Digesta passage in the rabbit could not be modelled mathematically using data on digesta passage due to complexities of the system. In contrast, a basic model was constructed for digesta passage in the ringtail possum. On the basis of these findings, the research hypothesis "that digesta passage in rabbits is similar to that in ringtail possums" was rejected.
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Van, Wyk Anna Maria. "Digesta markers for evaluating the effect of exogenous enzymes on nutrient digestibility in beef feedlot cattle." Diss., University of Pretoria, 2017. http://hdl.handle.net/2263/63348.
Full textAbstract:
The Food and Agriculture Organization (FAO) stated that it is vital to intensify animal
and feed production in a sustainable manner. Producers are therefore increasing focus
on methods to improve production efficiency. The use of exogenous enzymes in
ruminant diets can improve production efficiency while also reducing waste products,
thereby contributing to more sustainable food production. There are many
combinations of enzymes that first have to be screened through in vitro methods,
thereby selecting a number of enzyme combinations with the highest potential
effectiveness. Ultimately, however, the best combinations need to be validated using in
vivo digestibility studies. Ruminants, in general, have variable responses to
supplementation with exogenous enzymes and the animal response to different
enzymes can be influenced by the type of enzyme or combinations used as well as the
experimental conditions. The in vivo validation of prototype enzymes by means of
digestibility studies is therefore of utmost importance before commercialisation of a
product.
To measure total tract digestibility the total faecal collection method is normally used.
Total faecal collection is, however, labour intensive because all the faeces produced in a period of time must be collected and the animals must be confined to individual housing
which may disturb the animals. Marker-based methods are less labour intensive are an
attractive alternative to the total faecal collection technique. Before any marker can be
used in digestibility studies, it should be validated to confirm the suitability of the
specific marker in a specific diet.
The aim of this study was first to evaluate the effect of different enzyme prototypes on
feedlot diet digestibility and secondly to validate different markers as an alternative to
total faecal collection in digestibility studies using high maize feedlot diets.
Six ruminally cannulated steers were used to evaluate the apparent total tract nutrient
digestibility using two different enzyme prototypes against a control diet. The steers
were fed twice daily and received either the control diet or a control diet supplemented
with either enzyme A or enzyme B. Three different markers, chromic (III) oxide (Cr2O3),
acid insoluble ash (AIA) and acid detergent lignin (ADL) were validated against total
faecal collection to determine which marker is most suitable in digestibility studies for
feedlot diets containing high levels of maize (60%) and low levels of roughage (20%).
The mean apparent total tract digestibility (TTD) for dry matter (DM), starch and crude
protein (CP) showed no difference (P>0.05) between the control diet and diets
supplemented with enzyme A or enzyme B. The neutral detergent fibre (NDF)
digestibility did show a difference (P<0.05) between the control diet and the diet
supplemented with enzyme B. However there were no differences (P>0.05) between
the control diet and the diet supplemented with enzyme A or between the two diets
supplemented with the enzymes A and B. Acid insoluble ash and Cr2O3 showed no
difference (P>0.05) between treatments in its ability to predict digestibility when
compared to total faecal collection. Acid detergent lignin predictions differed (P<0.05) from total collection and is probably unsuitable to be used as a marker in high maize
feedlot diets.
The use of enzymes containing xylanase, amylase and protease had no effect on
nutrient total tract digestibility in our study; however, the enzyme-containing xylanase
and β-glucanase had an effect on apparent total tract NDF digestibility. Both AIA and
Cr2O3 can be used as markers to determine apparent total tract nutrient digestibilities in
feedlot diets with a high maize content based on a comparison with the total faecal
collection. Acid detergent lignin appears to be a poor marker in high concentrate
feedlot diets due to the low ADL content of the diet.Dissertation (MSc Agric)--University of Pretoria, 2017.
Animal and Wildlife Sciences
MSc (Agric)
Unrestricted
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Magadlela, Andrew Mtutuzeli. "An evaluation of n-alkanes as markers to estimate dry matter intake, diet selection and solid digesta passage rates in ruminants." Thesis, University of Edinburgh, 2001. http://hdl.handle.net/1842/28523.
Full textAbstract:
Study 1 (exp 1, 2, and 3) assessed the use of alkanes for estimating diet composition and intake in lambs. In exp 1, 36 lambs at 30% and 45% of projected mature sizes were used in a factorial design with 2 breeds (Suffolk and Scottish Blackface), two sexes (male and female) and three feed treatments [pelleted lucerne (Medicago sativa) or pelleted ryegrass (Lolium spp) alone or both as a choice] to compare alkane-derived estimates of dry matter intake (DMI) and selected diet with direct measurements. In exp 2, to assess diurnal variation in n-alkane concentration in the gut, 6 restricted and 6 ad libitum fed lambs at 45% mature size were used in a split-plot design to compare the ratios of the amount of dotriacontane (C32) to tritriacontane (C33) in the faeces collected at 4 hourly intervals over a 24 hour period. In exp 3, to evaluate the efficacy of dosing once-daily (cf. twice-daily) with C32, 6 once-daily and 6 twice-daily dosed lambs were used in a split-plot design to compare faecal alkane ratios of C33 to C32. Exp 1 suggested general agreement between measured quantities and those estimated using the alkane technique However, at 30% mature size, for the lambs fed on grass only, dry matter intake was slightly overestimated and for those fed on lucerne and grass as a choice, dry matter intake of lucerne was underestimated. Exp 2 indicated that the ratio of the concentration of C33:C32 in the faeces was not affected by sampling time and thus no diurnal variation irrespective of whether the lambs were restricted or ad libitum fed. Experiment 3 suggested no difference in the ratios of the concentrations of C33:C32 between the two dosing strategies until the fifth day of dosing. Study II used the alkane pair of C36 and C35 to compare the voluntary dry matter intake of Brachiaria decumbens by 8 dry cows, averaging 301 kg liveweight and 8 lactating Criollo cows averaging 320 kg liveweight during the wet season and 8 lactating cows averaging 300 kg liveweight and 7 dry cows, averaging 289 kg liveweight during the dry season of Bolivia. Results suggested that this alkane pair can be used to estimate the dry matter of intake of tropical forages, but if the concentrations of C35 are very low the accuracy of the estimate may be compromised.
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Raggi, Thiago. "Feeding and nutrition of tropical farmed fish and shrimp: pellet water stability, in vitro protein digestion, comparison of inert markers, evaluation of practical feeds, and dietary amino acid requirement." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/21/21134/tde-17022017-093822/.
Full textAbstract:
The aim of this thesis was to evaluate the feeding and nutrition of tropical farmed fish and shrimp, targeting its applicability to aquaculture farming. The study of the actual panorama of aquafeed quality for tilapia Oreochromis niloticus and shrimp Litopenaeus vannamei farmed in Brazil showed that the proximate compositions between the analyzed feeds were mostly consistent with the declared values from the manufacturers, however, the feed water stability showed the opposite; the in vitro pH-stat species-specific method to determine the protein degree of hydrolysis (DH) showed to be a useful tool to evaluate feed quality; and NIRS technique can be used in many applications throughout the aquafeed industry, being an efficient tool for rapidly assessing feed quality in terms of DH. A second study evaluated the acid-insoluble ash (AIA) and chromic oxide (Cr2O3) as inert markers and feed processing method (industrial extruded vs. laboratory cold pelleted) to determine apparent digestibility coefficient (ADC) of dry matter and crude protein of juvenile L. vannamei. The AIA showed to be an effective natural endogenous marker for digestibility trials with L. vanammei, however, for commercial feeds attention should be paid to feed AIA level; the extruded feed showed better animal performance than the cold pelleted feed, however, ADC of both feeds were not significantly different from each other. Further, two feeding trials were conducted with juvenile cobia Rachycentron canadum: (1) feeding trial conducted within floating net cages to test the nutritional efficacy of different dietary feeding regimes ranging from the use of trashfish, in-house formulated feeds, to dry commercial extruded marine fish feed; and (2) feeding trial conducted within indoor water-recirculated tanks to test the nutritional efficiency of different potential dietary fishmeal replacers within dry in-house prepared diets. Generally, fish performance was superior in the net-cage feeding trial compared with the indoor water-recirculated tank trial; overall, the fish growth and performance of the experimental diets were very similar, showing that the alternative ingredients could be included and replace part (50%) of the fishmeal component; the results from both trials concluded that the cobia requires practices diets with high levels of crude protein and lipid, and the inclusion of alternative plant-based and terrestrial animal protein sources was possible; the quantitative essential amino acid (EAA) requirement values estimated by the protein accretion method was highly correlated to the average of each of the EAA requirement for the species of carnivorous fish reported in the literature, and could be recommended for formulation of commercial feed for cobia R. canadum. Finally, a tentative to quantify the total sulfur amino acid requirement of juvenile Florida Pompano Trachinotus carolinus, was performed using combinations of various soybean protein products in order to develop cost-effective and environmentally-friendly diets. Although there was an apparent tendency in the results, the range of methionine levels employed in this study may not have been broad enough to accurately measure the dietary concentration necessary to estimate the total sulfur amino acid requirement; in addition, high variation results among the three replicates per diet did not provide sufficiency robustness for its estimation; this study within 45 days should not have been enough to show significant differences among the treatments. Long term feeding trials would be recommended from fingerling/juvenile to market size with full nutritional and economic evaluation of results.O objetivo dessa tese foi avaliar a alimentação e nutrição de peixes e camarões tropicais cultivados, visando a sua aplicação à aquicultura. O estudo do atual panorama da qualidade das rações para tilapia e camarão cultivados no Brasil mostrou que a maioria das composições proximais das rações analisadas foram consistentes com os valores declarados pelos fabricantes, porém, a estabilidade das na água mostrou-se o oposto; o método in vitro pH-stat com enzimas espécie-específica, para determinação do grau de hidrólise da proteína (DH), mostrou ser uma ferramenta útil para avaliar a qualidade das rações; a técnica da espectrofotometria do infravermelho próximo (NIRS) pode ser usada em várias aplicações na indústria de alimentos aquáticos, sendo uma ferramenta eficiente para avaliar rapidamente a qualidade dos alimentos em termos de DH. Um segundo estudo avaliou a cinza insolúvel em ácido (AIA) e óxido de cromo (Cr2O3) como marcadores inertes, além de métodos de processamento de alimentos (extrusado industrial vs. peletizada a frio no laboratório) para determinar o coeficiente de digestibilidade aparente (ADC) da matéria seca e proteína bruta de juvenis de L. vannamei. O AIA mostrou ser um marcador endógeno natural eficaz para ensaios de digestibilidade com L. vanammei, no entanto, atenção especial deve ser dada aos níveis de AIA nas rações comerciais; a ração extrusada teve a melhor performance dos animais, porém, os valores de ADC entre as rações não foram diferentes significantemente. Além disso, dois experimentos de alimentação foram conduzidos com juvenis de beijupirá Rachycentron canadum: (1) experimento realizado em tanques-rede flutuantes para testar a eficácia nutricional de diferentes regimes alimentares, variando entre rejeito de pesca, rações preparadas em laboratório, e ração comercial extrusada; e (2) um experimento realizados em tanques com recirculação de água para testar a eficiência nutricional de diferentes potenciais substitutos de farinha de peixe, com dietas completadas preparadas em laboratório. Em geral, o desempenho dos peixes foi superior no experimento nos tanques-rede, comparado com o experimento nos tanques de recirculação de água; no geral o crescimento e performance dos peixes das dietas experimentais foram bem similares, concluindo que ingredientes alternativos podem ser incluídos e substituírem parte (50%) da farinha de peixe das rações; os resultados de ambos os estudos concluíram que o beijupirá requer dietas práticas com alto teores de proteína bruta e lipídeos, e a inclusão de fontes proteicas de origem vegetal e animal foi possível. Os valores quantitativos das exigências de amino acido essenciais (EAA) estimados pelo método de acreção de proteína na carcaça foram altamente correlacionados com as médias de exigência de cada EAA das as espécies de peixes carnívoros encontrados na literatura, e pode ser recomendado para a formulação de ração comercial para beijupirá R. canadum. Por ultimo, uma tentativa de quantificar as exigências de amino ácidos sulforosos totais para Florida Pompano Trachinotus carolinus, foi realizada utilizando combinações de vários ingredientes proteicos a base de soja, a fim de desenvolver dietas de baixo custo e ecologicamente sustentáveis. Embora houve uma tendência clara nos resultados, os intervalos dos níveis de metionina utilizados nesse estudo podem não ter sido amplos o suficiente para medir com precisão a concentração alimentar necessária para estimar a exigência dos de amino ácidos sulforosos totais; além disso, a alta variação entre as replicas não forneceu uma estimativa robusta; este estudo de 45 dias não deve ter sido suficiente para mostrar diferenças significativas entre os tratamentos.
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Barthe, Catherine. "Contribution a l'etude de la cfp (cystic fibrosis protein) proteine serique marqueur de la mucoviscidose." Aix-Marseille 2, 1988. http://www.theses.fr/1988AIX22048.
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OFORI, REGINA. "DEVELOPMENT OF AN IN VITRO ASSAY TO EVALUATE ANTIMICROBIALS." 2012. http://hdl.handle.net/10222/15131.
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In vitro assays were developed using small intestinal contents from broilers fed
maltodextrin in preparation for shipping. This was done to establish an effective
bactericidal dose of allicin or lysozyme as ingredients in maltodextrin-based feed. The
antimicrobials were added to overnight cultures of gut material bacteria from
maltodextrin fed broilers and a pure culture of Salmonella. Following this, lysozyme was
incorporated into maltodextrin feed at 0, 10 and 20 g.kg-1 of feed and offered for 9 h to 4
pens of 20 birds per treatment. Bacterial numbers were analyzed using Proc Mixed of
SAS. Allicin and lysozyme inhibited Enterobacteriaceae and Clostridium perfringens,
respectively, in vitro. Lysozyme showed the most promise; it reduced bacterial numbers
in nutrient broth. Feeding lysozyme-enriched maltodextrin for 9 h inhibited bacilli growth
(P<0.05) when evaluated using next generation sequencing. Lysozyme was effective in
reducing specific bacterial numbers in the gut of market-aged broilersThe project focused on ways to ensure poultry meat safety by controlling bacteria population in the gastrointestinal tract of market-aged broilers prior to shipping.
Books on the topic "Digesta markers"
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Nobel, Peter. Finanzmarktrechtliche Entscheide: Praxis zum schweizerischen Finanzmarktrecht. 2nd ed. Bern: Stämpfli, 2006.
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Packaging digest: Trends in consumer packaging preferences, 1993-1995. Des Plaines, IL: Cahners Pub. Co., 1995.
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Murphy, Patrick D. Conclusion. University of Illinois Press, 2017. http://dx.doi.org/10.5406/illinois/9780252041037.003.0007.
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The conclusion digests the main issues explored in the previous chapters. The core argument put forward is that the global media landscape that materialized at the end of the twentieth century has become a central mediator of eco-consciousness around the globe. This landscape is defined primary by the Promethean discourse, which assumes that growth is perpetual and that individuals operating within the market have the agency to solve any and all environmental problems. This discourse is problematic when considered in the face of anthropogenic climate change and declining natural resource reserves. However, even powerful discourses co-produced and are hence not immune to challenges. This means that alternative environmental discourses can be found within market driven media, suggesting that while the contemporary media commons is the domain of non-ecologically responsive normative trends, its also offers openings for more progressive environmental thought and action.
Book chapters on the topic "Digesta markers"
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Pascali, V. L., E. d’Aloja, M. Dobosz, M. Pescarmona, and A. Fiori. "Allele frequencies distribution of two VNTR markers (YNH24; YNZ22) in PST I digests from random Italian individuals (population of Rome)." In Advances in Forensic Haemogenetics, 68–70. Berlin, Heidelberg: Springer Berlin Heidelberg, 1990. http://dx.doi.org/10.1007/978-3-642-75496-8_19.
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Cascio, Elio Lo. "Setting the Rules of the Game." In Roman Law and Economics, 111–36. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780198787204.003.0005.
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This chapter analyses the mainly juridical evidence (from the Digest and the late antique Codes, as well as Cassiodorus’ Variae) on the working of the market in the Roman Empire and the role played by the imperial authority in regulating it, in the light of the conceptualizations of the new institutional economics. This evidence seems to suggest undeniably not only that the economy of the Roman Empire, from its very beginning in the late Republic to late antiquity, was characterized by the free market, but also that maintaining competitive markets was the consistent and deliberate policy of the Roman authority throughout the whole of Roman history.
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Bouchaud, Jean-Philippe, J. Doyne Farmer, and Fabrizio Lillo. "How Markets Slowly Digest Changes in Supply and Demand." In Handbook of Financial Markets: Dynamics and Evolution, 57–160. Elsevier, 2009. http://dx.doi.org/10.1016/b978-012374258-2.50006-3.
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Shildrick, Tracy. "Poverty, labour markets and ‘poor work’." In Poverty Propaganda, 65–86. Policy Press, 2018. http://dx.doi.org/10.1332/policypress/9781447323976.003.0004.
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This chapter looks at working-class employment. Millions of people experience poverty despite their commitment to working hard in paid employment, which fails to raise them out of poverty. This issue is an increasingly important piece of the poverty jigsaw in contemporary Britain; but it remains hidden behind the simply and easily digested rhetoric of poverty propaganda. An overriding conclusion from many years of researching these sorts of issues in deprived neighbourhoods with high rates of worklessness is that it is very difficult to find people who have never had a job or who choose a lifetime on out-of-work benefits, even when one is determinedly searching for them in some of the most deprived locales in the UK.
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Sperber, Daniel. "Administration and Organization of the Market." In The City in Roman Palestine. Oxford University Press, 1999. http://dx.doi.org/10.1093/oso/9780195098822.003.0006.
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To operate a market, or fair, individuals and communities needed the sanction of the Roman senate or the emperor. We are told that the Emperor Claudius held markets on his estates. Pliny mentions in one of his Letters that “Sollers, a man of praetorian rank, petitioned the Senate to be allowed to establish a market on his estate. His petition was opposed by envoys from Vicetia—no doubt because there was a market in that town which stood to lose from Sollers’ competition.” An inscription from 138 C.E. describes how a new market was established at Casae in the Roman province of Africa Proconsularis. The founding of this market required a specific vote of the Senate at Rome and granted Lucilius Africanus, a senator, permission to hold a market twice a month on a regular basis. The official decision of the Senate was formulated as follows: . . .Concerning this matter the senate decreed as follows: that Lucilius Africanus, vir clarissimus, be permitted to establish and maintain a market at Casae in the province of Africa, Beguensian district, territory of the Musulamians, on November 2 and 20 and every month there in the fourth day before the Nones and the twelfth day before the Kalends, and that people from the neighbourhood be permitted to gather and assemble there for the convenience of attending market only, without harm or inconvenience to anyone. . . . . . . But what was the real effect of the decision of the Roman Senate? John E. Stanbaugh gives us a hint in his book The Ancient Roman City: “Lurking clearly between the lines of the inscription are the prospect of big profits for Lucilius and the desire of the authorities that the market not become the focus of any political activity.” Normally, after receiving permission to establish a market, it became subject to the authority of the city prefect. Cicero writes that “there will be aediles who will oversee the city’s markets, merchandise, and food supplies. . . .”, while from the Digesta we learn that “It is his job to see that meat is offered for sale at a fair price, and for this reason the swine market is . . . under his supervision. Similarly other livestock which are used to provide meat are within his jurisdiction.”
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Nemchinova, Tamara S., and Anton A. Muzalev. "Export of education: comparative analysis of Russian and Turkish practices in the post-soviet space." In DIGEST OF WORLD POLITICS. ANNUAL REVIEW. VOLUME 10, 484–506. St. Petersburg State University, 2020. http://dx.doi.org/10.21638/11701/26868318.32.
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The article assesses the export potential of Russian and Turkish universities. The influx of foreign citizens to study at universities is the most important quality criterion for the country’s higher education system. It is also an indicator of the country’s integration into the world community and a major export item. The leaders in the number of students from other countries have traditionally been the United States, Great Britain, France, the USSR, and Germany. At the turn of XX — XXI centuries. a significant increase in foreign students is observed in Australia, Japan, China. Other countries are also taking steps to improve the national higher education system and, accordingly, increase the number of foreign students. But attempts to penetrate the world market of educational services are significantly complicated, the market is already thoroughly divided, and the states that have long been entrenched in it are not going to allow new players to enter it. This process is also taking place in Turkey, which is one of the fastest growing economies in the world.
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Eichengreen, Barry. "Managing Problem Debts." In In Defense of Public Debt, 77–92. Oxford University PressNew York, 2021. http://dx.doi.org/10.1093/oso/9780197577899.003.0006.
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Abstract This chapter focuses on debt crises in the nineteenth century. Lending to sovereigns, then as now, posed risks, especially when governments defaulted on loans contracted abroad. Foreign investors had limited recourse against the sovereign. Defaults spiked in the 1820s, 1870s, and 1890s. Ultimately, however, the market emerged stronger from each crisis. Existing solutions to deter opportunistic sovereigns were revamped, from pledging collateral to external financial control. New institutions, such as investment banks acting as gatekeepers and bondholder committees representing the interests of investors, further supported the operation of the market. The steamship and telegraph provided improved access to information about foreign countries, which was then digested and disseminated by specialized investment services. Investors learned to diversify away some of the risk in their portfolios, with help from managed investment funds.
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Kehoe, Dennis P. "Mandate and the Management of Business in the Roman Empire." In Roman Law and Economics, 307–38. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780198787204.003.0011.
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This chapter examines the role that the contract of mandate (mandatum) and the related institution of “unauthorized administration” (negotia gesta) played in Roman economic life. Mandate represented a major form of agency in Roman society, but it presents problems of incentives because it was uncompensated: the agent might carry out significant tasks for the principal, or mandator; these tasks might involve considerable expense and even financial risk on the part of the agent, but the agent was not to profit from his service. On the basis of juridical evidence from the Digest and the Code of Justinian, I examine how mandate transformed a relationship that had its roots in upper-class Roman notions of friendship and reciprocity into a contractual form that remained useful as it provided property owners advantages with high-valued financial transactions, such as the purchase of property. In addition, it provided a useful way for Roman businesspeople to overcome problems of information in the credit market.
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Bricca, Jacob. "Archival Material." In How Documentaries Work, 147—C8.N1. Oxford University PressNew York, 2023. http://dx.doi.org/10.1093/oso/9780197554104.003.0009.
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Abstract Chapter 8 investigates the use of archival documents in documentaries, interrogating how they are visually manipulated to deliver an artificial sense of authenticity and how they are used to quickly and superficially place an event in historical context. The markers of age (scratches, etc.) that many archival documents contain can be used by a documentary to make a particular section feel “authentic,” even though this is arguably artificial since there is no neutral way to present archival material. (Removing scratches is just as easily accomplished as adding them, and any telecine transfer will have to choose parameters for how the image should be represented.) It is not uncommon to accentuate an image’s seeming “archival” value, for instance, by including the sprocket holes on the side of the film frame even though this is actually a postproduction effect rather than a product of the transfer process. Newspaper articles have routinely had their context manipulated throughout the history of documentary in order to make them more easily digested by audience members; multiple examples from the series Tiger King: Murder, Mayhem, and Madness show that such manipulation is even more sophisticated today. Documentaries will often use the clichéd moments from a historical archive in order to quickly evoke an era and bring it into the narrative.
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Keats, Jonathon. "(-///-)." In Virtual Words. Oxford University Press, 2010. http://dx.doi.org/10.1093/oso/9780195398540.003.0030.
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The snigger point, or note of cachinnation, was invented by Ambrose Bierce in 1887. He proposed the new typographic symbol as “an improvement in punctuation,” explaining in an essay that “it is written thus ︶ and represents, as nearly as may be, a smiling mouth. It is to be appended, with the full stop, to every jocular or ironical sentence; or, without the stop, to every jocular or ironical clause of a sentence otherwise serious.” Recommended to humorless colleagues who had no trouble recognizing his sarcasm, the snigger point, or note of cachinnation, never caught on. Similar suggestions have since been advanced, independently, with different motivations. In 1899 the French writer Alcanter de Brahm earnestly proposed that a backward question mark be used in print as a point d’ironie , an idea that Alfred Jarry fervently endorsed two years later, though both the irony mark and its creator faded into obscurity shortly thereafter. And in 1967 Reader’s Digest ran a short item by the Baltimore Sunday Sun correspondent Ralph Reppert, whose Aunt Ev seasoned her family letters with the symbol –) representing “her tongue stuck in her cheek,” an idea recirculated on an ARPANET mailing list in 1979 in a proposal to counteract “the loss of meaning in this medium [due to] the lack of tone, gestures, facial expressions, etc.” The ARPANET community never embraced Aunt Ev’s innovation. But three years later a slightly different icon was rapidly and permanently adopted. The emblem was first playfully circulated on the Carnegie Mellon University bulletin board system by a computer scientist, Scott Fahlman: . . . 19-Sep-82 11:44 Scott E Fahlman :-) From: Scott E Fahlman <Fahlman at Cmu-20c> I propose that the following character sequence for joke markers: :-) Read it sideways. Actually, it is probably more economical to mark things that are NOT jokes, given current trends. For this, use :-( . . . The :-( symbol was enthusiastically taken up together with the :-), though not in the way Fahlman intended.
Conference papers on the topic "Digesta markers"
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Enpuku, K. "Magnetic immunoassay with SQUID and magnetic marker." In INTERMAG Asia 2005: Digest of the IEEE International Magnetics Conference. IEEE, 2005. http://dx.doi.org/10.1109/intmag.2005.1463685.
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Berson, Bert, and Joyce Peterson. "Wireless Market: Implications for RF Test&Measurement." In 42nd ARFTG Conference Digest. IEEE, 1993. http://dx.doi.org/10.1109/arftg.1993.327034.
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Niedzwiecki, Antoni C. "Test Strategy for RF&Microwave Semiconductor Devices for Wireless Communications Market." In 45th ARFTG Conference Digest. IEEE, 1995. http://dx.doi.org/10.1109/arftg.1995.327098.
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Lee, Hong Ro, Jung Sub Shin, and Chi Jung Hwang. "Invisible Marker Tracking System Using Image Watermarking for Augmented Reality." In 2007 Digest of Technical Papers International Conference on Consumer Electronics. IEEE, 2007. http://dx.doi.org/10.1109/icce.2007.341310.
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Kalsum, Leila, Yordan Hasan, Rusdianasari, Rusdianasari, Aida Syarif, Dayaningrat Dayaningrat, and Syaiful M. "Biogas and Electrical Energy Production from Market Waste at Fixed Dome Bio-digester in Talang Banjar Jambi." In 5th FIRST T1 T2 2021 International Conference (FIRST-T1-T2 2021). Paris, France: Atlantis Press, 2022. http://dx.doi.org/10.2991/ahe.k.220205.034.
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Bidaut, Luc. "Multimodality and Advanced Biomedical Imaging for Clinical and Research Applications." In ASME 2010 First Global Congress on NanoEngineering for Medicine and Biology. ASMEDC, 2010. http://dx.doi.org/10.1115/nemb2010-13314.
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Driven in particular by the availability of ever more refined imaging modalities — such as faster and higher resolution CT and MR, or hybrid PET/CT and SPECT/CT — and by a marked increase in computing power, advanced biomedical imaging — e.g. through its multidimensional and multimodal paradigms — is taking an ever bigger place in both research and clinical routine, and for both diagnostic applications and therapy management. While human modalities are widely publicized, there is a similar plethora of imaging systems for small animals, which permits relatively fast translation of successful image-based protocols from research evaluation to the clinic. Because of their characteristics and the need for more detailed information about normal vs. diseased tissues, modern modalities produce huge amounts of information and images. The only way to digest these is through advanced paradigms that combine or reduce the complexity of the information so that it can be interpreted by normal human beings. This presentation will introduce techniques and research or clinical applications of advanced imaging for both animals and humans.
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Effinger, Mark, Josh Mauzey, and Vince McDonell. "Characterization and Reduction of Pollutant Emissions From a Landfill and Digester Gas Fired Mictroturbine Generator." In ASME Turbo Expo 2005: Power for Land, Sea, and Air. ASMEDC, 2005. http://dx.doi.org/10.1115/gt2005-68520.
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Distributed Generation (DG), where small-scale power generation capacity is installed at or near its point of use, is of growing interest to reduce the need for the addition of traditional, large, centralized power plants. Microturbine generators (MTGs) represent one type of DG platform, applications for which continue to expand as the technology improves. MTGs have already shown flexibility in operation on alternatives fuels, making them a potential candidate for use in the renewable energy market. However, many renewable fuels, such as gases produced at wastewater treatment plants and landfills, have significantly lower heating values than pure natural gas. Due to lower volumetric energy content, these waste gases are commonly referred to as medium-BTU fuels. While examples of MTGs operating on these renewable fuels grow in number, little detailed information on the systematic effect of fuel composition on MTG performance is available. The current study characterizes emissions performance of a commercial natural gas fired MTG operating on medium-BTU fuel and identifies the relationship between fuel composition and emissions performance over a 50 to 100% load profile. Results from the implementation of a new injector designed to reduce emissions are also presented.
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Steger, H. "Graphical object-oriented multimedia application development: technology and market trends." In COMPCON '96. Technologies for the Information Superhighway Digest of Papers. IEEE, 1996. http://dx.doi.org/10.1109/cmpcon.1996.501786.
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Federici, A. B., and S. D. Berkowitz. "CARBOHYDRATE PREVENTS LOSS OF LARGE VON WILLEBRAND FACTOR MULTIMERS BY PROTECTING AGAINST AMINO TERMINAL PROTEOLYTIC CLEAVAGE." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1642873.
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We have previously shown that carbohydrate (CHO) protects von Willebrand factor (vWF) from proteolytic degradation. We have now shown that removal of CHO from the vWF subunit exposes additional cleavage sites in the amino terminal region and that cleavages in this region are associated with loss of large multimers. We examined and compared the extent of large multimer loss with sites of subunit cleavage of native and GHO-modified vWF after treatment with plasmin, chymotrypsin, and trypsin. Highly purified vWF was treated with neuraminidase and β-galactosidase in the presence of proteinase inhibitors to remove 90-95% of the sialic acid and 45-50% of the D-galactose without loss of large multimers or diminution of the ristocetin cofactor activity. The extent and approximate location of subunit cleavage was determined by immunoblotting and monoclonal antibody epitope mapping. Multimeric analysis revealed an increasingly greater loss of large multimers when native vWF was digested with plasmin, chymotrypsin, and trypsin, respectively. Large multimer loss was more extensive with each enzyme after CHO-modification of vWF. On subunit analysis, plasmin, chymotrypsin, and trypsin were shown to produce both amino and carboxy terminal fragments. The number, location, and relative quantities of carboxy terminal fragments produced by these enzymes were unchanged after CHO modification. However, digestion of the amino terminal region was considerably more extensive as judged by a marked decrease or absence of the larger fragments seen when native vWF was digested, and by the appearance of new smaller molecular weight species. Thus, enzymatic digestion of vWF after removal of carbohydrate produced new cleavages in the amino terminal region but did not alter the location or extent of carboxy terminal cleavages. Therefore, the greater loss of large multimers that occurs after CHO modification is likely to be the result of cleavages in the amino terminal region of the molecule. It appears that by protecting the vWF subunit against amino terminal cleavage, carbohydrate inhibits the loss of large multimers.
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Ghezel-Ayagh, Hossein, Anthony J. Leo, Hans Maru, and Mohammad Farooque. "Overview of Direct Carbonate Fuel Cell Technology and Products Development." In ASME 2003 1st International Conference on Fuel Cell Science, Engineering and Technology. ASMEDC, 2003. http://dx.doi.org/10.1115/fuelcell2003-1697.
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Significant progress has been made in development of power generation products based on carbonate fuel cells. Carbonate fuel cell systems provide high efficiency and ultra-clean power generation from a variety of gaseous, liquid, and solid carbonaceous fuels. The high operating temperature of 650 °C in carbonate fuel cell allows significant system simplification by integrating the internal reforming feature into the fuel cell stack as well as use of the byproduct heat in an efficient bottoming cycle. Direct FuelCell® (DFC®) is a unique version of the carbonate fuel cell, which generates electricity directly from a hydrocarbon fuel by reforming the fuel inside the fuel cell and producing hydrogen. The direct reforming concept eliminates the need for an external reformer resulting in power plants with reduced capital cost. This feature also allows the DFC power plants to utilize the existing fuel distribution infrastructure. The first generation of products offered by FuelCell Energy (FCE) range from 250kW to 2MW and is suitable to operate on natural gas, digester gas and other fuels. Presently, a fleet of natural gas fueled units is operating in the US and Europe at customers’ sites. Additionally, there are subsequent power plants planned to operate on a variety of fuels, including coal-bed methane, digester gas, and coal-derived gas. A 2 MW fuel cell power plant (DFC3000) will soon be operating with coal gas in Wabash River, Indiana’s coal gasification plant. The field tests of a 1 MW unit (DFC1500) at King County (Seattle, WA) waste treatment will be demonstrating the unique features of the DFC technology with digester gas as a fuel. There are plans to operate a 250 kW (DFC300) unit on coal-bed methane fields in Cadiz, Ohio. FCE is also developing a 500 kW unit for the US NAVY, operating on marine distillate fuels. FCE is also developing fuel cell/turbine ultra-high efficiency hybrid power plants with efficiencies approaching 75%. In the Direct FuelCell/Turbine® (DFC/T®) power cycle, the fuel cell is integrated with an indirectly heated gas turbine. FCE has recently completed the operation of a ‘proof-of-concept’ system that combined a sub-megawatt DFC with a 30-kilowatt microturbine. The proof-of-concept tests demonstrated that the DFC/T hybrid concept, indeed, has the potential for achieving higher efficiencies than the single cycle fuel cell. The demonstration of two, packaged sub-megawatt DFC/T units, one in Danbury and one at a customer site in Montana, is planned. In addition to pioneering the Direct FuelCell technology, FCE has established a strong manufacturing base. Currently the manufacturing facility at Torrington, CT, has the equipment in place to produce 50 MW per year of fuel cells. FCE has also established commercial distribution alliances with electric power equipment sales and service companies, energy service and solution providers, and specialty application developers for marketing DFC products. The operation of FCE’s power plants at customer sites, continuing efforts in technology improvement, and the favorable reception of the customers for DFC-based units, combined with a network of partners for sales and services, are the key factors for market penetration of DFC products.
Reports on the topic "Digesta markers"
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Ginn, Thomas, ed. JDC Quarterly Digest on Labor Market Access and Outcomes for Refugees. World Bank - UNHCR Joint Data Center on Forced Displacement, January 2023. http://dx.doi.org/10.47053/jdc.300123.
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Refugees’ right to work is protected by international law but often violated in practice. This Digest discusses the barriers that host governments impose on refugees’ labor market access and reviews the academic research on the effects of these policies and practices have on refugees and host communities. As expected, barriers like employment bans significantly harm refugees’ living conditions in most contexts where research is available. However, the evidence also suggests that most segments of the host communities benefit little and may in fact be harmed by restrictions on refugees’ work.
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Rhykerd, Robert, Thomas Bierma, Guang Jin, and Paul Walker. Economic and Environmental Assessment of Switchgrass Production on High-Fertility Soil and an Assessment of Anaerobic Digests as an Intermediate Market for Switchgrass. Office of Scientific and Technical Information (OSTI), March 2014. http://dx.doi.org/10.2172/1126616.
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