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81.
82.
Eliel González‐García Yann Alexandrine Tatiana Silou‐Etienne Harry Archimède 《Journal of the science of food and agriculture》2009,89(11):1918-1926
BACKGROUND: The in situ technique (IS) is used for characterising, screening and evaluating feedstuffs in ruminants. However, it is often not adapted to the particular characteristics of feeds (i.e. kinetics of starchy feeds with a standard framework used in forage). This may lead to potential biases in the final conclusions. In two successive experiments, we evaluated the degradative characteristics of conventional (CON) and unconventional (UNC) starchy feedstuffs (ING) and factors affecting their washable fractions (WF). The suitability of IS was then assessed. RESULTS: Two well‐defined ruminal fermentation patterns (CON and UNC) were observed. The WF and insoluble washable (ISWF) fractions were affected by ING, state of presentation [WAY, fresh (F) or pre‐dried (D)], particle size (PSI) and their interactions. The UNC and F feeds had greater WF and ISWF than CON and D, respectively. Increasing PSI linearly reduced WF and its proportion of ISWF. CONCLUSION: The PSI and WAY are critical factors to consider when designing experiments for the evaluation of starchy feedstuffs for ruminants using IS. It is still very risky to propose ‘standard’ parameters as this will always depend on the particular ING evaluated. Conducting pre‐evaluation tests before implementing each research protocol could help to refine the procedure. Copyright © 2009 Society of Chemical Industry 相似文献
83.
Sam L. J. Page Md Elahi Baksh Etienne Duveiller Stephen R. Waddington 《Food Security》2009,1(1):99-109
This paper reports on a ‘bottom-up’ system of wheat seed technology transfer that was piloted in north–west Bangladesh with
45 mainly marginal (food insecure) farming families during the 2004–2005 wheat season, then scaled out to a further 545 mainly
marginal, farming families during the 2006–2007 season. The system was devised following a survey which indicated that such
farmers can obtain a 52% increase in wheat grain yield and extra income by switching from the old Kanchan variety to the newer, heat and disease-tolerant Shatabdi variety. The bottom-up wheat seed dissemination system involved the creation of an enabling environment which allowed poor
and ultra-poor farmers to store and sell selected seed of recently-released wheat varieties that they produced in 20 decimal
(0.08 ha) plots. During the pilot phase of the project in 2005, farmers produced 7, 976 kg of grain and more than 50% of this
was selected as high quality seed, stored during the monsoon season and marketed to other farmers just prior to the following
wheat season. This seed was sold at Tk25–30/kg and realised profits averaging Tk3,002 (€38.49; exchange rate was 78:1 in October
2005) per household. In 2007, the seed price had risen to Tk33–50/kg and a larger group of farmers produced, stored and marketed
168,800 kg of high quality wheat seed, which realised profits averaging Tk5,080, equivalent to €51 (exchange rate was 99.6:1
in October 2007), per household. This bottom up seed production and dissemination system met the wheat seed requirements of
more than 1,400 neighbouring farmers in areas with a deficit of wheat seed for planting, and enabled poor and ultra-poor farmers
to earn more than 50% of the income they needed to cross the local poverty line.
Sam L. J. Page Ph.D. I have been working in rural development for more than 30 years in both government and non-government sectors. My early research was concerned with pest management in food cropping systems and later I began investigating underlying causes of household food insecurity in southern Africa, as well as the use of indigenous food cropping systems to mitigate the impacts of HIV/AIDS. I am currently based at CABI Europe-UK, where I am implementing the Good Seed Initiative which aims to alleviate poverty by enabling food insecure farming families to profit from producing and marketing seed of indigenous and improved varieties. Dr. Baksh is an experienced agricultural economist and Principal Scientific Officer in the Wheat Research Centre of the Bangladesh Agricultural Research Institute (BARI). He specialises in economic aspects of the rice–wheat cropping system that characterises much of south Asia and has published 20 scientific papers. For the past 8 years he has been the Principal Investigator for several DFID, IFAD, IRRI and CIMMYT funded projects that aim to design and disseminate resource-conserving technologies to improve the livelihoods of the poorest farming families in the region. Dr. Etienne Duveiller is a plant pathologist specializing in cereal disease resistance and integrated crop management with more than 25 years experience in international agriculture and development projects. He received his M.Sc. (1980) and Ph.D. (1992) from University of Louvain (UCL) in Belgium and a special degree in social sciences from the Developing Countries Institute at the same university (1981). After working in capacity building in Bolivia for an NGO, and in Burundi on rice diseases, he joined CIMMYT Wheat Program in 1987. After10 years at CIMMYT headquarters in Mexico and frequent visits to South Asia, he spent 8 years on the Indian Subcontinent as CIMMYT regional pathologist based in Nepal and participated in several wheat disease surveys in central Asia and Iran. He returned to Mexico in 2006 as Head of Wheat Pathology at the CIMMYT Global Wheat program. Stephen Waddington is an agronomist. He has 26 years of experience working with the International Maize and Wheat Improvement Centre (CIMMYT) and its partners in Mexico, southern and eastern Africa and in Bangladesh. His main research interests involve smallholder farming systems and participatory research, maize and wheat crop production agronomy, soil fertility and water management, and cereal yield physiology. He has considerable experience in capacity building and networking in many of these areas. Waddington was South Asia regional agronomist and head of the CIMMYT Office in Bangladesh from 2005 to 2007 and is currently located in Mexico. 相似文献
Stephen R. WaddingtonEmail: |
Sam L. J. Page Ph.D. I have been working in rural development for more than 30 years in both government and non-government sectors. My early research was concerned with pest management in food cropping systems and later I began investigating underlying causes of household food insecurity in southern Africa, as well as the use of indigenous food cropping systems to mitigate the impacts of HIV/AIDS. I am currently based at CABI Europe-UK, where I am implementing the Good Seed Initiative which aims to alleviate poverty by enabling food insecure farming families to profit from producing and marketing seed of indigenous and improved varieties. Dr. Baksh is an experienced agricultural economist and Principal Scientific Officer in the Wheat Research Centre of the Bangladesh Agricultural Research Institute (BARI). He specialises in economic aspects of the rice–wheat cropping system that characterises much of south Asia and has published 20 scientific papers. For the past 8 years he has been the Principal Investigator for several DFID, IFAD, IRRI and CIMMYT funded projects that aim to design and disseminate resource-conserving technologies to improve the livelihoods of the poorest farming families in the region. Dr. Etienne Duveiller is a plant pathologist specializing in cereal disease resistance and integrated crop management with more than 25 years experience in international agriculture and development projects. He received his M.Sc. (1980) and Ph.D. (1992) from University of Louvain (UCL) in Belgium and a special degree in social sciences from the Developing Countries Institute at the same university (1981). After working in capacity building in Bolivia for an NGO, and in Burundi on rice diseases, he joined CIMMYT Wheat Program in 1987. After10 years at CIMMYT headquarters in Mexico and frequent visits to South Asia, he spent 8 years on the Indian Subcontinent as CIMMYT regional pathologist based in Nepal and participated in several wheat disease surveys in central Asia and Iran. He returned to Mexico in 2006 as Head of Wheat Pathology at the CIMMYT Global Wheat program. Stephen Waddington is an agronomist. He has 26 years of experience working with the International Maize and Wheat Improvement Centre (CIMMYT) and its partners in Mexico, southern and eastern Africa and in Bangladesh. His main research interests involve smallholder farming systems and participatory research, maize and wheat crop production agronomy, soil fertility and water management, and cereal yield physiology. He has considerable experience in capacity building and networking in many of these areas. Waddington was South Asia regional agronomist and head of the CIMMYT Office in Bangladesh from 2005 to 2007 and is currently located in Mexico. 相似文献
84.
Stam MR Danchin EG Rancurel C Coutinho PM Henrissat B 《Protein engineering, design & selection : PEDS》2006,19(12):555-562
Family GH13, also known as the alpha-amylase family, is the largest sequence-based family of glycoside hydrolases and groups together a number of different enzyme activities and substrate specificities acting on alpha-glycosidic bonds. This polyspecificity results in the fact that the simple membership of this family cannot be used for the prediction of gene function based on sequence alone. In order to establish robust groups that show an improved correlation between sequence and enzymatic specificity, we have performed a large-scale analysis of 1691 family GH13 sequences by combining clustering, similarity search and phylogenetic methods. About 80% of the sequences could be reliably classified into 35 subfamilies. Most subfamilies appear monofunctional (i.e. contain enzymes with the same substrate and the same product). The close examination of the other, apparently polyspecific, subfamilies revealed that they actually group together enzymes with strongly related (or even sometimes virtually identical) activities. Overall our subfamily assignment allows to set the limits for genomic function prediction on this large family of biologically and industrially important enzymes. 相似文献
85.
Anna Devlin Jane McGillivray Judith Charlton Georgia Lowndes Virginie Etienne 《Accident; analysis and prevention》2012
While there is a large body of research indicating that individuals with moderate to severe dementia are unfit to drive, relatively little is known about the driving performance of older drivers with mild cognitive impairment (MCI). The aim of the current study was to examine the driving performance of older drivers with MCI on approach to intersections, and to investigate how their healthy counterparts perform on the same driving tasks using a portable driving simulator. Fourteen drivers with MCI and 14 age-matched healthy older drivers (aged 65–87 years) completed a 10-min simulator drive in an urban environment. The simulator drive consisted of stop-sign controlled and signal-controlled intersections. Drivers were required to stop at the stop-sign controlled intersections and to decide whether or not to proceed through a critical light change at the signal-controlled intersections. The specific performance measures included; approach speed, number of brake applications on approach to the intersection (either excessive or minimal), failure to comply with stop signs, and slower braking response times on approach to a critical light change. MCI patients in our sample performed more poorly than controls across a number of variables. However, because the trends failed to reach statistical significance it will be important to replicate the study using a larger sample to qualify whether the results can be generalised to the broader population. 相似文献
86.
A simple explicit photovoltaic formulation for characterizing and dimensioning cell-arrays is presented. The method permits the short-circuit current, the open-circuit voltage, the maximum cell power and the optimum cell-operation conditions to be determined. Further, the model also allows quantifying the effects of panel temperature and solar irradiance on key cell parameters. Based on several datasheets, the methodology is validated by covering a wide range of operation conditions. The proposed approach can thus, be very useful for design engineers to quickly and easily determine the performance of any photovoltaic array without performing tedious numerical calculations. 相似文献
87.
Radiation-induced precipitation and segregation in a cold-worked 316 austenitic stainless steel irradiated with 10 MeV Fe5+ ions were characterized by atom probe tomography. Ni and Si enrichment and Cr depletion were observed in roughly spherical and torus-shaped clusters, believed to be due to solute enrichment and depletion at dislocation loops. Solute segregation was also observed at network dislocations. These observations are consistent with the phenomenon of radiation-induced segregation. Radiation-induced segregation at grain boundaries was also studied at the near atomic scale. Comparison of these observations with results from the literature shows a difference in the magnitude of the peak concentration of segregated solutes. 相似文献
88.
Fluorescence spectroscopy coupled with independent components analysis to monitor molecular changes during heating and cooling of Cantal‐type cheeses with different NaCl and KCl contents 下载免费PDF全文
89.
Etienne J. F. R. Caron Amir R. Baserinia Harry Ng Mary A. Wells David C. Weckman 《Metallurgical and Materials Transactions B》2012,43(5):1202-1213
Thermal modeling of the direct-chill casting process requires accurate knowledge of (1) the different boundary conditions in the primary mold and secondary direct water-spray cooling regimes and (2) their variability with respect to process parameters. In this study, heat transfer in the primary cooling zone was investigated by using temperature measurements made with subsurface thermocouples in the mold as input to an inverse heat conduction algorithm. Laboratory-scale experiments were performed to investigate the primary cooling of AA3003 and AA4045 aluminum alloy ingots cast at speeds ranging between 1.58 and 2.10 mm/s. The average heat flux values were calculated for the steady-state phase of the casting process, and an effective heat-transfer coefficient for the global primary cooling process was derived that included convection at the mold surfaces and conduction through the mold wall. Effective heat-transfer coefficients were evaluated at different points along the mold height and compared with values from a previously derived computational fluid dynamics model of the direct-chill casting process that were based on predictions of the air gap thickness between the mold and ingot. The current experimental results closely matched the values previously predicted by the air gap models. The effective heat-transfer coefficient for primary cooling was also found to increase slightly with the casting speed and was higher near the mold top (up to 824 W/m2·K) where the molten aluminum first comes in contact with the mold than near the bottom (as low as 242 W/m2·K) where an air gap forms between the ingot and mold because of thermal contraction of the ingot. These results are consistent with previous studies. 相似文献
90.
Influence of Metronidazole Particle Properties on Granules Prepared in a High-Shear Mixer-Granulator
Piera Di Martino Roberta Censi Ledjan Malaj Sante Martelli Etienne Joiris Christine Barthélémy 《Drug development and industrial pharmacy》2013,39(2):121-131
ABSTRACTMetronidazole is a good example of high-dose drug substance with poor granulating and tableting properties. Tablets are generally produced by liquid granulation; however, the technological process failure is quite frequent. In order to verify how the metronidazole particle characteristics can influence granule properties, three metronidazole batches differing for crystal habit, mean particle size, BET surface area and wettability were selected, primarily designed according to their different elongation ratio: needle-shaped, stick-shaped, and isodimensional. In the presence of lactose monohydrate and pregelatinized maize starch, respectively as diluent and binder, they were included in a formula for wet granulation in a high-shear mixer-granulator. In order to render the process comparable as far as possible, all parameters and experimental conditions were maintained constant. Four granule batches were obtained: granules from placebo (G-placebo), granules from needle-shaped crystals (G-needle-shaped), granules from stick-shaped crystals (G-stick-shaped), and granules from isodimensional crystals (G-isodimensional). Different granule properties were considered, in particular concerning porosity, friability, loss on drying (LOD), and flowability. In order to study their tabletability and compressibility, the different granules obtained were then compressed in a rotary press. The best tabletability was obtained with the isodimensional batch, while the poorest was exhibited by the stick-shaped one. Differences in tabletability are in good accordance with compressibility results: to a better tabletability corresponds an important granule ability to undergo a volume reduction as a result of an applied pressure. In particular, it was proposed that the greatest compressibility of the G-isodimensional must be related to the greatest granule porosity percentage. 相似文献