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Mycobacteria in water, feedstocks and food: analysis of publications 全文
2010
Kaevska, M.,Vyzkumny Ustav Veterinarniho Lekarstvi, Brno (Czech Republic) | Hruska, K.,Vyzkumny Ustav Veterinarniho Lekarstvi, Brno (Czech Republic)
Papers on mycobacteria in food, feed and water, published between 1945 and 2010 and indexed in the database Web of Science (Thomson Reuters), were ranked according to authors, institutions, countries and source titles. The total number of papers on mycobacteria and food, and mycobacteria and water were 1,486 and 1,419, respectively. More than 40% of papers have been published in the last five years. In addition to publications in peer reviewed journals the archives of ProMED-mail and the Rapid Alert System for Food and Feed of the European Union were also searched. It is evident that much attention is being paid to mycobacteria in food, feed and water as they likely pose a public health risk.
显示更多 [+] 显示较少 [-]Water activity changes of multicomponent food mixture during processing 全文
Stencl, J.(Mendelova Zemedelska a Lesnicka Univ., Brno (Czech Republic). Ustav Zemedelske, Potravinarske a Environmentalni Techniky) | Komprda, T.(Mendelova Zemedelska a Lesnicka Univ., Brno (Czech Republic). Ustav Technologie Potravin)
The objective of this study was to determine the changes in water activity and moisture content in the dry fermented sausages Herkules, a typical multicomponent food, during ripening and storage. The sausages were made with lean beef, lean pork, pork fat, nitrite salt mixture, and sugars, and fermented with two starter cultures (Pediococcus pentosaceus + Staphylococcus carnosus and S. carnosus + S. xylosus + Lactobacillus farciminis). The samples were taken and tested during ripening (21 days) and storage (91 days). The water activity was measured by indirect manometric method in a static environment, the moisture content by halogen dryer. The water activity and moisture content decreased considerably, but very irregularily during the ripening, whereas they declined only slowly and linearly during the storage. The decrease during the storage was expressed by mathematical equations describing the changes of water activity and moisture content in function of the time. The use of different starter cultures had no influence on the two variables studied.
显示更多 [+] 显示较少 [-]Food handling by the gregarious Mediterranean water shrew Neomys anomalus
1999
Rychlik, L. (Polish Academy of Sciences, Bialowieza (Poland). Mammal Research Inst.)
Foraging behaviour of gregarious Mediterranean water shrew Neomys anomalus was investigated in 7 individuals. Shrews were tested individually and in a 4-animal-group in a terrarium. Shrew behaviour was recorded in darkness using 2 infra-red sensitive video-cameras. Two experimental variants, with and without natural structures in the terrarium, were established. When foraging individually, N. anomalus consumed only few food portions at the places of finding. Shrews hoarded most food in the nest and/or in hiding-places and ate it under cover. The presence of natural structures caused hoarding and eating of food in scattered hiding-places, instead of carrying it to the nest. During group foraging, N. anomalus did not hoard food communally, and preparation of individual stores almost ceased. In all tests, they ate successively more food items at the places of finding as the duration of foraging increased.
显示更多 [+] 显示较少 [-]Irrigation schedules for selected food crops using water balance book-keeping method
2014
Ezemonye, M.N., University of Benin, Benin City (Nigeria). Dept. of Geography and Regional Planning | Emeribe, C.N., University of Benin, Benin City (Nigeria). Environmental Pollution Remediation Unit
In the tropics, the water potential of a region cannot be adequately assessed from precipitation alone due to the seasonal character of rainfall and even more so owing to the changing climate scenario. It is therefore necessary that in any agro-climatological program, there must be a clear understanding of the actual amount of water that evaporates and transpires (AET), and the amount of water that would evaporate and transpire if water were always readily available (PET). This could be done through the method of the water balance. The present work examines the water budget of parts of the Imo river basin and its implications for improved crop production through supplementary irrigation schedules. It was observed, that the study area is already facing moisture-stress. This is because even during rainy months supplementary irrigation is required to compensate for the occasionally moisture deficit due to increased evapotranspiration. The study showed that cultivation of maize, rice and tomatoes can be carried out on an all-year round basis under a scientific irrigation scheme. Thus the study provided farmers with guideline on the period and quantity of water required for supplementary irrigation, a development which will prevents wilting of plants before the application of needed water.
显示更多 [+] 显示较少 [-]Biosynthesis of food constituents: Vitamins. 2. Water-soluble vitamins: Part 2 - a review 全文
2007
Velisek, J.,Vysoka Skola Chemicko-technologicka, Prague (Czech Republic). Ustav Chemie a Analyzy Potravin | Cejpek, K.,Vysoka Skola Chemicko-technologicka, Prague (Czech Republic). Ustav Chemie a Analyzy Potravin
This review article gives a survey of the biosynthetic pathways that lead to water-soluble vitamins in microorganisms, plants and some animals. The biosynthetic pathways leading to some of the B-group vitamins (biotin, folacin, cobalamins) and to vitamin C are described in detail using reaction schemes and mechanisms with enzymes involved and detailed explanations based on chemical principles and mechanisms.
显示更多 [+] 显示较少 [-]The food of common bream (Abramis brama L.) in a biomanipulated water supply reservoir 全文
2012
Zapletal, T., Mendelova Univ., Brno (Czech Republic). Ustav Zoologie, Rybarstvi, Hydrobiologie a Vcelarstvi | Mares, J., Mendelova Univ., Brno (Czech Republic). Ustav Zoologie, Rybarstvi, Hydrobiologie a Vcelarstvi | Jurajda, P., Akademie Ved, Brno (Czech Republic). Ustav Biologie Obratlovcu | Vsetickova, L., Akademie Ved, Brno (Czech Republic). Ustav Biologie Obratlovcu
Food composition of Abramis brama was studied in the shallow, meso-eutrophic Hamry reservoir (Czech Republic). Fish were sampled during the daytime in the pre-spawning period (April), the post-spawning (June), summer (July) and autumn (October) in 2011. The bream sampled comprised two main size groups: small (124-186 mm) and large (210-315 mm) standard length. Twenty specimens of each size group (except April - 40 large fish) were taken for analysis on each sampling occasion. Food composition was evaluated using gravimetric methods. Over the whole season, detritus and aquatic vegetation were the dominant dietary items taken. During summer, the diet of large bream comprised mainly aquatic vegetation. Benthic macroinvertebrates and zooplankton formed a minor part of bream diet over the whole season. Specific food habits of bream could be explained by specific conditions within the reservoir and available food resources.
显示更多 [+] 显示较少 [-]Food storage, prey remains and notes on occasional vertebrates in the diet of the Eurasian water shrew, Neomys fodiens
2002
Haberl, W.
The food remains of Neomys fodiens (particularly trichopteran larvae, Gastropoda and Amphibia) found on the banks of ponds and small creeks in Lower Austria are described. Characteristic bite marks, the manner of opening the cases and shells, as well as data on feeding patterns are presented. Food caches mainly consisted of caddis fly larvae and snails, but also contained non-palatable items which shrews apparently had confused with real prey and retrieved. The composition of the caches varied seasonally, showing a marked mid-summer decline and a shift in the proportion of Trichoptera and Mollusca in late summer and autumn. Shrews employed particular methods when breaking snail shells and opening caddis fly cases, and in the consumption of vertebrate carcasses.
显示更多 [+] 显示较少 [-]Role of juvenile hormone in the hypermetabolic production of water revealed by the O2 consumption and thermovision images of larvae of insects fed a diet of dry food 全文
2013
Slama, K., Czech Academy of Sciences, Prague (Czech Republic). Inst. of Entomology | Lukas, J., Crop Research Institute, Prague (Czech Republic)
The young larvae of insects living on dry food produce large amounts of water by the metabolic combustion of dietary lipids. The metabolic production of water needed for larval growth, previously known as hypermetabolic responses to juvenile hormone (JH), is associated with a 10 to 20-fold increase in the rate of O2 consumption (10,000 microL O2/g/h in contrast to the usual rate of 500 microL O2/g/h). Growing and moulting larvae are naturally hypermetabolic due to the endogenous release of JH from the corpora allata. At the last, larval-pupal or larval-adult moult there is no JH and as a consequence the metabolic rate is much lower and the dietary lipid is not metabolized to produce water but stored in the fat body. At this developmental stage, however, a hypermetabolic response can be induced by the exogenous treatment of the last larval instars with a synthetic JH analogue. In D. vulpinus, the JH-treated hypermetabolic larvae survive for several weeks without moulting or pupating. In T. castaneum and G. mellonella, the JH-treated hypermetabolic larvae moult several times but do not pupate. All these larvae consume dry food and the hypermetabolic response to JH is considered to be a secondary feature of a hormone, which is produced by some subordinated endocrine organ. The organ is most probably the controversial prothoracic gland (PG), which is a typical larval endocrine gland that only functions when JH is present. According to our hypothesis, PG activated by JH releases an adipokinetic superhormone, which initiates the conversion of dietary lipid into metabolic water. This type of metabolic combustion of dietary lipid produces large quantities of endothermic energy, which is dissipated by the larvae in the form of heat. Thermovision imaging revealed that the body of hypermetabolic larvae of G. mellonella can be as hot as 43 deg C or more. In contrast, the temperature of "cold" normal last instar larvae did not differ significantly from that of their environment. It is highly likely that thermovision will facilitate the elucidation of the currently poorly understood hormonal mechanisms that initiate the production of metabolic water essential for the survival of insects that live in absolutely dry conditions.
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