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Alternative prediction methods of protein and energy evaluation of pig feeds

Journal of Animal Science and Biotechnology 2017年第4期8卷 799-812页

作者： ewa swiech The Kielanowski Institute of Animal Physiology and Nutrition Polish Academy of SciencesJablonnaPoland

Precise knowledge of the actual nutritional value of individual feedstuffs and complete diets for pigs is important for efficient livestock production. Methods of assessment of protein and energy values in pig feeds have been briefly described. In vivo determination of protein and energy values of feeds in pigs are time-consuming,expensive and very often require the use of surgically-modified animals. There is a need for more simple, rapid,inexpensive and reproducible methods for routine feed evaluation. Protein and energy values of pig feeds can be estimated using the following alternative methods: 1) prediction equations based on chemical composition; 2)animal models as rats, cockerels and growing pigs for adult animals; 3) rapid methods, such as the mobile nylon bag technique and in vitro methods. Alternative methods developed for predicting the total tract and ileal digestibility of nutrients including amino acids in feedstuffs and diets for pigs have been reviewed. This article focuses on two in vitro methods that can be used for the routine evaluation of amino acid ileal digestibility and energy value of pig feeds and on factors affecting digestibility determined in vivo in pigs and by alternative methods. Validation of alternative methods has been carried out by comparing the results obtained using these methods with those acquired in vivo in pigs. In conclusion, energy and protein values of pig feeds may be estimated with satisfactory precision in rats and by the two-or three-step in vitro methods providing equations for the calculation of standardized ileal digestibility of amino acids and metabolizable energy content. The use of alternative methods of feed evaluation is an important way for reduction of stressful animal experiments.

关键词： Energy value In vitro Pig Protein value Rat

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Natural Organic Amendments for Improved Phytoremediation of Polluted Soils:A Review of Recent Progress

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Pedosphere 2016年第1期26卷 1-12页

作者： Alina WISZNIEWSKA ewa HANUS-FAJERSKA ewa MUSZYIISKA Krystyna CIARKOWSKA Institute of Plant Biology and Biotechnology Faculty of Biotechnology and HoricultureUniversity of AgricultureKrakow 31-425(Poland) Department of Soil Science and Soil Protection Faculty of Agriculture and EconomicsUniversity of AgricutureKrakow 31-120(Poland)

Environmental pollution caused by metals, radionuclides and organic pollutants affects quality of the biosphere: soil, water and ***, great efforts have been made to reduce, remove or stabilize contaminants in polluted sites. There has been increasing interest in phytoremediation—the use of plants to reduce concentration of pollutants or to render them harmless. This paper provides a brief review of recent progress in the research and practical application of phytoremediation techniques. Improvements in phytoremediation due to utilization of organic amendments, namely, agro- and industrial wastes(such as sugar beet residue, composted sewage sludge or molasses), biochar, humic substances, plant extracts and exudates are discussed, as well as their influences on soil structure and characteristics, plants growth and bioavailability of pollutants. Both plant-assisted phytoremediation and the use of natural materials in the absence of remediating plant are believed to be cost-effective and environmentally friendly approaches for soil cleanup. However,the characterization and quantification of a range of natural materials used in phytoremediation are essential in order to implement these approaches to practice.

关键词： agricultural wastes bioavailability biochar contamination natural chelators toxic elements

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Suppression of bile acid synthesis by thyroid hormone in primary human hepatocytes

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World Journal of Gastroenterology 2006年第29期12卷 4640-4645页

作者： ewa Cristine Siljevik Ellis Department of Medicine Division of Gastroenterology and Hepatology and the Department of Laboratory MedicineDivision of Clinical ChemistryKarolinska University Hospital at HuddingeKarolinska InstituteStockholmSweden

AIM： It is known that thyroid hormones alter the bile acid metabolism in humans, however the effect on individual enzymes has been difficult to elucidate. This is mainly due to the lack of human liver cell lines producing bile acids. We used cultures of primary human hepatocytes to study the effects of triiodothyronine （T3） on bile acid synthesis.METHODS： Primary hepatocytes were isolated from liver tissue obtained from three different patients undergoing liver resection due to underlying malignancy. The hepatocytes were cultured under serum-free conditions and treated from d 1 to d 5 with culture containing 0.1 - 1000 nmol/L of T3. Bile acid formation and mRNA levels of key enzymes were analysed. RESULTS： The lowest concentration of T3 decreased cholic acid （CA） formation to 43%-53% of controls and chenodeoxycholic acid （CDCA） to 52%-75% of controls on d 5. The highest dose further decreased CA formation to 16%-48% of controls while CDCA formation remained at 50%-117% of controls. Expression of mRNA levels of cholesterol 7α-hydroxylase （CYP7A1） and sterol 12α-hydroxylase （CYPSB1） dose-dependently decreased. Sterol 27-hydroxylase （CYP27A1） levels also decreased, but not to the same extent. CONCLUSION： T3 dose-dependently decreased total bile acid formation in parallel with decreased expression of CYP7A1 and CYP8B1. CA formation is inhibited to a higher degree than CDCA, resulting in a marked decrease in the CA/CDCA ratio.

关键词： Hepatocytes Human Bile acids CYP7A1 CYPSB1 CYP27A1

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Unique Factorization of Compositive Hereditary Graph Properties

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Acta Mathematica Sinica,English Series 2012年第2期28卷 267-280页

作者： Izak BROERE ewa DRGAS-BURCHARDT Department of Mathematics University of Johannesburg Department of Mathematics and Applied Mathematics University of PretoriaPretoria0002South Africa Faculty of Mathematics Computer Science and Econometrics University of Zielona Góra

A graph property is any class of graphs that is closed under isomorphisms, A graph property P is hereditary if it is closed under taking subgraphs; it is compositive if for any graphs

关键词： Graph property hereditary compositive property unique factorization minimal forbid-den graphs reducibility

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The break-up tendency of long rod projectiles

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Defence Technology（防务技术） 2016年第2期12卷 177-187页

作者： ewa LIDéN Andreas HELTE FOI Swedish Defence Research Agency

A model for the tendency of fragmentation of a long rod projectile subjected to armour components in add-on armours such as reactive armour and active protection systems is presented. The model is based on studies of the interaction between a cylindrical streamlined projectile and moving thin plates(backwards moving like the front plate in a reactive armour panel and forwards moving like the rear plate in a reactive armour panel).The assumption behind the model is that the sliding force, with velocity vslidebetween the projectile and the plate, gives rise to a transverse velocity vtransof the projectile segment it passes, which will deflect the projectile segment. This deflection is assumed to be a major reason for the fractures that can emerge along the projectile. The velocity, geometry and material of the projectile and the plate are of importance for the fragmentation of the projectile and the dimensionless parameterδ? = v trans vslideexpresses how these parameters influence the break-up tendency. Experiments and simulations have verified that the identifiedδ?-parameter predicts an increased amount of fragmentation of the projectile with increasing value of this parameter.

关键词：长杆弹破裂反应装甲趋势模型主动防护系统横向速度无量纲参数附加装甲

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(De) Constructing Sentences

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外国语 2013年第1期36卷 2-15页

作者： ewa Dabrowska Northumbria University UK

Lexically specific units,i.e.,formulaic frames(Where's Daddy? What's Mummy doing?) and frames with slots(***'s NP? Do you want to VP?) are known to play a central role in language *** such mechanisms also account for adult production? I argue that the types of representations and production mechanisms that constructivist language researchers have postulated for children can also explain the basic mode of adult language use,*** *** adult language in such terms not only captures the continuity between child and adult usage,but also helps to explain how speakers are able to produce and understand language as fast as they do: using preconstructed chunks saves processing ***,adults also have more abstract linguistic ***,however,are acquired relatively late in acquisition,largely as a result of experience with written texts,and may not be acquired by all speakers.

关键词：语言学语言理论语言规划分类

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Satyrization and satyrization-resistance in competitive displacements of invasive mosquito species

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Insect Science 2016年第2期23卷 162-174页

作者： Irka ewa Bargielowski Leon Philip Lounibos Florida Medical Entomology Laboratory University of Florida Vero Beach Florida USA

Competitive displacements or reductions of resident populations of insects, often effected by a related species, may be caused by a variety of mechanisms. Satyrization is a form of mating interference in which males of one species mate with females of another species, significantly decreasing their fitness and not generating hybrids. Satyriza- tion has been established to be the probable cause of competitive displacements of resident mosquitoes by invasive species, especially of Aedes aegypti by Aedes albopictus, two important vectors of dengue and chikungunya viruses. Mathematical models predict that even low levels of asymmetric mating interference are capable of producing competitive displacements or reductions. Couplings of virgin Ae. aegypti females with Ae. albopictus males effectively sterilize these females through the monogamizing actions of male ac- cessory gland products, but the converse interspecific mating does not impact the future reproduction ofAe. albopictus females. Populations ofAe. aegypti exposed to satyrization quickly evolve resistance to interspecific mating, which is believed to ameliorate repro- ductive interference from, and promote co-existence with, Ae. albopictus. The evolution of satyrization resistance among Ae. aegypti in laboratory cages is accompanied by fitness costs, such as reduced fecundity and slower receptivity to conspecific males. Cage exper- iments and field observations indicate that Ae. albopictus males are capable of satyrizing females of other species of the Stegomvia subgenus, potentially leading to competitive displacements, and possible extinctions, especially of endemic species on islands. Exam- ination of other examples of reproductive interference in insects reveals few parallels to the mechanism and outcomes of satyrization by Ae. albopictus. We conclude by posing the hypothesis that satyrization may favor the ecological success of Ae. albopictus, and suggest many lines for future research on this phenomenon.

关键词： Aedes aegypti Aedes albopictus mating interference reproductive interfer-ence satyrization

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C:N:P stoichiometry as an indicator of Histosol drainage in lowland and mountain forest ecosystems

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Forest Ecosystems 2021年第3期8卷 513-522页

作者： Jarosław Lasota ewa Błońska Department of Ecology and Silviculture Faculty of ForestryUniversity of Agriculture in Krakow29 Listopada 46 Str31-425 KrakówPoland

Background:Peatlands form one of the largest carbon pools in the terrestrial ecosystems,representing approximately one-third of the world’s soil *** aim of this study was to evaluate C:N:P stoichiometry as an indicator of changes initialized by dehydration in Histosols of varied *** types of Histosols from lowland and mountain areas were investigated:fibric Histosols,hemic Histosols,sapric Histosols and Histosols ***:We established the concentration and stoichiometry of carbon,nitrogen and phosphorous in the Histosols,and found marked differences in C:N:P stoichiometry between the different types–especially the dehydrated *** mean C:N:P ratio of dehydrated soil was narrower than the C:N:P ratio of soil under the influence of water,which demonstrates that dehydrating Histosols leads to a narrower C:N:P *** is directly related to the intensification of the organic matter mineralisation process and the resulting loss of organic *** recorded a 50%lower carbon stock in the case of Histosols drainic compared to the other types of ***:The narrower C:N:P stoichiometry in Histosols drainic is the result of an decrease in the ratio of N and P to the C ***,this study demonstrates that C:N:P stoichiometry is a useful indicator of the changes that occur in Histosols as a result of dehydration.

关键词： Dehydration Forest soils Lowland Mountain Peat soils

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Effect of spot burning of logging residues on the properties of mountain forest soils and the occurrence of ground beetles(Coleoptera, Carabidae)

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Journal of Mountain Science 2020年第1期17卷 31-41页

作者： Magdalena KACPRZYK ewa BLONSKA Jaroslaw LASOTA Department of Forest Protection Entomology and Forest ClimatologyUniversity of AgricultureAl.29 Listopada 4631-425 KrakowPoland Department of Forest Soil Science University of AgricultureAl.29 Listopada 4631-425 KrakowPoland

We investigated the relationships between dehydrogenase activity and the physicochemical properties of mountain soils over three and five years from Norway spruce(Picea abies L. Karst) logging residue spot burning and the occurrence of epigeic carabid beetles. Six study sites were utilised, including18 study plots(nine plots in a mixed coniferous mountain forest site and nine plots in a mixed broadleaf mountain forest site), with five replicate pitfall traps at each site located in southern *** samples from the organic horizon were taken for p H, organic carbon, nitrogen, base cation content,acidity and dehydrogenase activity *** beetles were monitored in weekly intervals during the period of July to August 2016. The burning of logging residues led to modified soil properties,especially the dehydrogenase activity. In all the tested variants, the activity was higher in soil samples after the burning in comparison to the control variants. We show no positive correlation between dehydrogenase activity and the number of carabid specimens. The preferences of dominant predatory hygrophilous carabids to acid habitats with weakly decomposed organic matter were proven. Simultaneously, the soil organic matter content was positively related to the carabid abundance. The significant impact of forest site conditions and the date of logging residue burning on the number of caught specimens were confirmed. In contrast, no relationships between the species richness, species diversity, mean individual biomass and spot burning effect were found. This work supports the recommendation of spruce fine woody debris utilisation by spot burning on mountain regions with rich habitats presenting moderate wet conditions and small land falls.

关键词： Fine woody debris Combustion Soil organic matter Enzyme activities Epigeic carabid beetles

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Decreased serum prohepcidin concentration in patients with polycythemia vera

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第11期10卷 791-795页

作者： Justyna KWAPISZ ewa ■EKANOWSKA Joanna JASINIEWSKA Department of Pathophysiology Nicolaus Copernicus University in ToruńCollegium Medicum in Bydgoszcz

Objective： Iron deficiency is a common complication in patients with polycythemia vera （PV）. Hepcidin is a principal regulator of iron homeostasis. The aim of our study was to assess prohepcidin, a hepcidin precursor, and other iron status pa- rameters in the serum of PV patients. Methods： The study was performed in 60 patients （F/M 26/34） aged 38-84 （66＋ 10） years. The control group consisted of 20 healthy volunteers, age and sex matched. The following parameters were determined in blood serum samples： prohepcidin concentration, iron content, unsaturated iron binding capacity （UIBC）, total iron binding capacity （TIBC）, transferrin saturation （TfS）, and concentrations of ferritin and soluble transferrin receptor （sTfR）. Results： All PV patients showed significantly lower levels of prohepcidin, higher levels of sTIR and TIBC compared to the control group. 40% of the patients from the study group showed concentrations of ferritin below the normal range and significantly lower levels of serum iron and TfS, and significantly higher levels of sTIR, UIBC and TIBC in comparison with the rest of the study group. In this group of patients, prohepcidin concentrations were significantly lower than those in other patients. Conclusion： The results indicate that PV patients suffer from iron metabolism disorders. The decreased serum level ofprohepcidin in PV patients may be a result of iron deficiency.

关键词： Polycythemia vera (PV) Iron metabolism Prohepcidin Hepcidin

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