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Assessing the Impacts of Summer Range on Bathurst Caribou’s Productivity and Abundance since 1985

Natural Resources 2014年第4期5卷 130-145页

作者： Wenjun Chen Lori White jan z. adamczewski Bruno Croft Kerri Garner Jody S. Pellissey Karin Clark Ian Olthof Rasim Latifovic Greg L. Finstad Canada Centre for Remote Sensing Natural Resources Canada Ottawa Canada Environment and Natural Resources Government of the Northwest Territories Yellowknife Canada School of Natural Resources and Agricultural Sciences University of Alaska Fairbanks USA Tlicho Government Behchoko Canada Wek'èez.ìi Renewable Resources Board Yellowknife Canada

Barren ground caribou are one of the most important natural resources for northern aboriginal peoples in Canada, and their responsible management has been identified as a top priority by northern communities and governments. This study is aimed to assess the impacts of summer range forage availability and quality on Bathurst caribou’s productivity and abundance. Despite well documented effects of habitat nutrition on individual animal, few studies have been able to link nutrition and population demographics in a quantitative fashion, probably because caribou productivity and abundance could be potentially affected by many factors (e.g., habitat, harvest, predators, diseases/parasites, extreme weather, climate change, industrial development, and pollution), and yet long-term data for many of these factors are not available. By determining the upper envelope curve between summer range indicators and caribou productivity, this study made such assessment possible. Our results indicate that summer range indicators derived from long-term remote sensing time series and climate records can explain 59% of the variation in late-winter calf:cow ratio during 1985 and 2012. As a measure of caribounet productvitiy, the late-winter calf:cow ratio, together with the mortality rate, in turn determined population dynamics.

关键词： Barren Ground Caribou Late-Winter Calf:Cow Ratio Summer Range Leaf Biomass Phenology Remote Sensing

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Postbiotics from Saccharomyces cerevisiae fermentation stabiliz. microbiota in rumen liquid digesta during grain-based subacute ruminal acidosis(SARA) in lactating dairy cows

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Journal of Animal Science and Biotechnology 2024年第5期15卷 2059-2080页

作者： Junfei Guo z.engxiao z.ang Le Luo Guan Ilkyu Yoon jan C.Plaiz.er Ehsan Khafipour Department of Animal Science University of ManitobaWinnipegMB R3T 2N2Canada Present Address:College of Food and Biological Engineering Jimei UniversityXiamenFujian 361021China Department of Agriculture Food and Nutrition DepartmentUniversity of AlbertaEdmontonAB T6G 2R3Canada Faculty of Land and Food Systems University of British ColumbiaVancouverBC V6T 1Z4Canada Diamond V Cedar RapidsIA 52404United States Present Address:Cargill Animal Nutrition 15407 McGinty Road WestWayzataMN 55391USA

Background Subacute ruminal acidosis(SARA)is a common metabolic disorder of high yielding dairy cows,and it is associated with dysbiosis of the rumen and gut microbiome and host *** study evaluated the impact of two postbiotics from Saccharomyces cerevisiae fermentation products(SCFP)on rumen liquid associated microbiota of lactating dairy cows subjected to repeated grain-based SARA challenges.A total of 32 rumen cannulated cows were randomly assigned to 4 treatments from 4 weeks before until 12 weeks after *** groups included a Control diet or diets supplemented with postbiotics(SCFPa,14 g/d Original XPC;SCFPb-1X,19 g/d Nutri Tek;SCFPb-2X,38 g/d Nutri Tek,Diamond V,Cedar Rapids,IA,USA).Grain-based SARA challenges were conducted during week 5(SARA1)and week 8(SARA2)after parturition by replacing 20%DM of the base total mixed ration(TMR)with pellets containing 50%ground barley and 50%ground *** DNA from rumen liquid samples was subjected to V3–V416S r RNA gene amplicon *** of rumen microbiota were compared among treatments and SARA *** Both SARA challenges reduced the diversity and richness of rumen liquid microbiota,altered the overall composition(β-diversity),and its predicted functionality including carbohydrates and amino acids metabolic *** SARA challenges also reduced the number of significant associations among different taxa,number of hub taxa and their composition in the microbial co-occurrence *** with SCFP postbiotics,in particular SCFPb-2X,enhanced the robustness of the rumen *** SCFP supplemented cows had less fluctuation in relative abundances of community members when exposed to SARA *** SCFP supplementation promoted the populations of lactate utiliz.ng and fibrolytic bacteria,including members of Ruminococcaceae and Lachnospiraceae,and also increased the numbers of hub taxa during non-SARA and SARA *** with S

关键词： Postbiotics Rumen microbiota Saccharomyces cerevisiae fermentation products SARA

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Calculation of the Standard Model Parameters and Particles Based on a SU(4) Preon Model

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Journal of Modern Physics 2024年第1期15卷 64-124页

作者： jan Helm Department of Electrical Engineering Technical University Berlin Germany

This paper describes an extension and a new foundation of the Standard Model of particle physics based on a SU(4)-force called hyper-color, and on preon subparticles. The hyper-color force is a generaliz.tion of the SU(2)-based weak interaction and the SU(1)-based right-chiral self-interaction, in which the W-and the z.bosons are Yukawa residual-field-carriers of the hyper-color force, in the same sense as the pions are the residual-field-carriers of the color SU(3) interaction. Using the method of numerical minimiz.tion of the SU(4)-action based on this model, the masses and the inner structure of leptons, quarks and weak bosons are calculated: the mass results are very close to the experimental values. We calculate also precisely the value of the Cabibbo angle, so the mixing matrices of the Standard model, CKM matrix for quarks and PMNS matrix for neutrinos can also be calculated. In total, we reduce the 29 parameters of the Standard Model to a total of 7 parameters.

关键词： SU(4) Generaliz.tion of Weak Interaction Extension of Standard Model Numerical Minimiz.tion of Action Hyper-Color Preon

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Specific detection of the floodwater mosquitoes Aedes sticticus and Aedes vexans DNA in predatory diving beetles

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Insect Science 2015年第4期22卷 549-559页

作者： Thomas z. Persson Vinnersten Peter Halvarsson jan O. Lundstrom Department of Ecology and Genetics Evolutionary Biology Centre Uppsala University SE-75236 Uppsala Swedish Biological Mosquito Control Project Nedre Dalalvens Utvecklings AB Gysinge Sweden

Floodwater mosquitoes （Diptera： Culicidae） are associated with periodically flooded wet meadows, marshes, and swamps in floodplains of major rivers worldwide, and their larvae are abundant in the shallow parts of flooded areas. The nuisance caused by the blood-seeking adult female mosquitoes motivates mosquito control. Larviciding with Bacillus thuringiensis israelensis is considered the most environmentally safe method. However, some concern has been raised whether aquatic predatory insects could be indi- rectly affected by this reduction in a potential vital prey. Top predators in the temporary wetlands in the River Dal/ilven floodplains are diving beetles （Coleoptera： Dytiscidae）, and Aedes sticticus andAe, vexans are the target species for mosquito control. For detailed stud- ies on this aquatic predator-prey system, we developed a polymerase chain reaction （PCR） assay for detection of mosquito DNA in the guts of medinm-siz.d diving beetles. Primers were designed for amplifying short mitochondrial DNA fragments of the cytochrome C oxidase subunit I （COI） gene in Ae. sticticus and Ae. vexans, respectively. Primer speci- ficity was confirmed and half-life detectability ofAe. sticticus DNA in diving beetle guts was derived from a feeding and digestion experiment. The Ae. sticticus DNA within diving beetle guts was detected up to 12 h postfeeding, and half-life detectability was estimated to 5.6 h. In addition, field caught diving beetles were screened for Ae. sticticus and Ae. vexans DNA and in 14% of the diving beetles one or both mosquito species were detected, showing that these mosquito species are utiliz.d as food by the diving beetles.

关键词： Aedes sticticus Dytiscidae floodwater mosquitoes gut content analysis half-life detectability PCR

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Influence of Organ Pathology on the Electrical Parameters in Organ Projection Areas of the Skin

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Journal of Traditional Chinese Medicine 2006年第3期26卷 218-225页

作者： jan z. Sz.pinski Georg P. Lochner Desmond Pantanowitz Pain Clinic Mayo Medical Centre of South Africa and University of the Witwatersrand Johannesburg South Africa Department of Electronic Engineering University of Pretoria Pretoria South Africa Department of Surgery Helen Joseph Hospital and University of the Witwatersrand Johannesburg South Africa

Pathology of an internal organ causes significant rectification of electrical currents （diode phenomenon） in related skin areas - organ projection areas （OPAs）, once the resistance ‘breakthrough effect＇ has been induced in the skin. Also, the impedance of the diseased organ＇s projection areas is increased. The aim of this double-blind study was to confirm these phenomena statistically using a broad spectrum of measuring parameters. Skin impedance vs. measurement frequency, skin impedance vs. applied voltage, and skin resistance vs. voltage were evaluated at 335 auricular OPAs related to the healthy internal organs and 203 auricular OPAs related to the diseased organs. These measurements confirmed that the skin electrical characteristics of specific locations are dependent on the health state of the corresponding internal organs. It was found that the impedance of OPAs corresponding to the healthy internal organs equals 185 ＋ 291 k,Q at 10Hz.and decreases to 64 ± 49 kΩ at 10kHz. and that the impedance of OPAs related to the diseased organs equals 7.5 ± 2.2 MΩ at 10Hz.and 99 ± 50kΩ at 10kHz. The disparity of the impedances between the healthy and diseased organs related OPAs is greater at higher potentials. The skin resistance, when measured with a negatively polariz.d point electrode, undergoes a rapid resistance decrease of approximately two orders of magnitude, if the applied current is sufficient. After this reversible ‘breakthrough effect＇ is obtained the skin exhibits rectification. The degree of rectification is low for OPAs related to the healthy organs. For OPAs related to the diseased organs, the resistance measured with a positive polarisation of measuring electrode could be five times greater than the resistance measured at the same voltage with the same but negatively polarised electrode. The disparity between the resistance measured with a negatively and with a positively polarised electrode at OPAs related to the diseased organs was greater at higher me

关键词： skin impedance skin resistance resistance ‘breakthrough effect' rectification acupuncture points

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Polymer solar cells with an inverted device configuration using polyhedral oligomeric silsesquioxane-[60]fullerene dyad as a novel electron acceptor

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Science China Chemistry 2012年第5期55卷 749-754页

作者： z.ANG Wen-Bin TU YingFeng SUN Hao-jan YUE Kan GONG Xiong CHENG Stephen z. D. College of Polymer Science and Polymer Engineering The University of Akron Akron OH 44325 USA College of Chemistry Chemical Engineering and Materials Science Soochow University Suzhou 215123 China

A polyhedral oligomeric silsesquioxane-[60]fullerene (POSS-C60) dyad was designed and used as a novel electron acceptor for bulk heterojunction (BHJ) polymer solar cells (PSCs) with an inverted device configuration. The studies of time-resolved photoinduced absorption of the pristine thin film of poly[(4,4'-bis(2-ethylhexyl)dithieno[3,2-b:2',3'-d]silole)-2,6-diyl-alt-(4,7-bis (2-thienyl)-2,1,3-benz.thiadiaz.le)-5,5'-diyl] (SiPCPDTBT) and the composite thin film of SiPCPDTBT:POSS-C60 indicated efficient electron transfer from SiPCPDTBT to POSS-C60 with inhibited back-transfer. BHJ PSCs made by SiPCPDTBT mixed with POSS-C60 yielded the power conversion efficiencies (PCEs) of 1.50%. Under the same operational conditions, PCEs observed from BHJ PSCs made by SiPCPDTBT mixed with [6,6]-phenyl-C61-butyric acid methyl ester were 0.92%. These results demonstrated that POSS-C60 is a potentially good electron acceptor for inverted BHJ PSCs.

关键词： electron acceptor polyhedral oligomeric silsesquioxane fullerene polymer solar cells inverted device structure

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Ability for Self-Pelletiz.tion of Iron Ores and Magnetite Concentrates

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Journal of Iron and Steel Research International 2011年第6期18卷 1-7页

作者： Francik Prz.mysaw jan Mróz Cz.stochowa University of Technology Czestochowa 42-200Poland

A procedure for evaluating the susceptibility of raw materials for the process of sintering of iron ore mixes is presented. The procedure relies on the evaluation of the amount and quality of the finest grain fraction. The method is based on determination of particular grain fractions. For the grain less than 0.15 mm, the determination of the a- mount is performed using an IPS （Infrared Particles Siz.r） grain siz. analyz.r and for the grain larger than 0.15 ram, the fraction is determined using the （wet and dry） screening methods. This allows for quantity assessment of the quality of material in terms of its susceptibility to self-pelletiz.ng by calculating Total Ability for SelPPelletiz.ng （TASP） index fT. The presented method, in combination with the grain siz. and chemical analyses, can serve for evaluation of suitability of raw material and mixes for the sintering process. Furthermore, the TASP index for 10 types of iron ores and concentrates was determined. The usability of the TASP index was verified by determination of its impact on yield of sintering process both in laboratory and in industry scale.

关键词： iron ore concentrate grain composition pelletiz.tion process sintering process productivity

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Leaching of blended copper slag in microwave oven

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Transactions of Nonferrous Metals Society of China 2017年第6期27卷 1404-1410页

作者： M.Deniz.TURAN z.Abidin SARI jan D.MILLER Department of Metallurgical and Materials Engineering University of Firat Department of Metallurgical Engineering University of Utah

Leaching of blended slag(BS)was investigated in a microwave oven using hydrogen peroxide and acetic *** BSwas a mixture of converter and flash furnace slag containing51%Fe2O3,3.8%CuO,and3.2%*** important variables thatinfluence the metal extraction yield were leaching time,liquid-solid ratio,H2O2and CH3COOH *** preferredleaching conditions were as follows:CH3COOH concentration4mol/L;H2O2concentration4mol/L;microwave power900W;leaching time30min;liquid-solid ratio25mL/g BS;leaching temperature100°*** these conditions,the metal extractions of95%Cu,1.6%Fe,and30%z. were *** results were compared with the traditional leaching *** is evident thatmicrowave heating causes a reduction in the leaching ***,the extraction yield results indicate that selective leaching of BS canbe achieved under the preferred *** dissolution kinetic of BS in hydrogen peroxide with acetic acid is controlled by ashrinking unreacted core model *** apparent activation energy and reaction order were found to be16.64kJ/mol and1.09,respectively.

关键词： slag copper microwave selective leaching

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Localiz.tion of Auricular Projection Area of the Liver and Its Use in the Monitoring of Viral Hepatitis

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Journal of Traditional Chinese Medicine 2006年第4期26卷 260-265页

作者： jan z. Sz.pinski Georg P. Lochner Tomasz.Macura Iwona Karcz.Socha Anna Kasprz.k-Minkner Krz.sz.of Kielan Barbara Krupa-Jez.erska Dariusz.J. Nasiek Piotr Warakomski 小红藤 Pain Clinic Mayo Medical Centre of South Africa and University of the Witwatersrand Johannesburg South Africa Department of Electronic Engineering University of Pretoria Pretoria South Africa Department of Infectious Diseases Provincial Teaching Hospital Tychy Poland Department of Internal Medicine Strzelce Opolskie Regional Hospital Poland Provincial Centre for Mother and Child Health Care Czestochowa Poland 1st Department of Psychiatry Silesian Medical University Katowice Poland Maciejow-z.brz. Medical Centre Zabrze Poland Department of Anaesthesia Newport Hospital Rhode Island USA Department of Physiology Silesian Medical University Zabrze Poland

Background： Pathology of an internal organ causes significant rectification of electrical currents （diode phenomenon） in related skin areas once the resistance ＇breakthrough effect＇ has been induced in the skin. Objective： Localiz.tion of auricular projection area of the liver and evaluation of its usefulness in the monitoring of viral hepatitis. Design, Patients and Setting： Comparative study of the degree of electrical rectification measured at various spots in the auricular concha region, in 19 inpatients with hepatitis B and 15 clinically healthy volunteers, at the Department of Infectious Diseases, Provincial Teaching Hospital, Tychy, Poland. Intervention： Evaluation of electrical rectification at various spots on the auricular concha using a ＂rectification ratio＂ that quantifies the degree of rectification （normal range： 0-60%）. Main outcome measure： The location of the skin area where a statistically significant difference existed between the rectification ratios was observed in patients （82±12% at the time of the ＇peak period＇） versus controls （42±8%）. Results： A location was identified on the ear auricle where the electrical rectification phenomenon demonstrated a dependence on the presence of hepatitis. Conclusions： Liver projection area exists on the ear auricle which is located within the region of cymba conchae, next to anthelix and the cavity of concha. The existence of viral hepatitis causes this skin area to show a higher degree of electrical rectification once the skin resistance ＇breakthrough effect＇ has been induced. Evaluation of the rectification phenomenon of the liver proiection area provides a method of non-invasive monitoring of viral hepatitis.

关键词： skin resistance resistance 'breakthrough effect' rectification acupuncture point organ electrodermal diagnostics (OED)

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Global methylation status of sperm DNA in carriers of chromosome structural aberrations

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Asian Journal of Andrology 2017年第1期19卷 117-124页

作者： Marta Olsz.wska Miroslawa z.Barcisz.wska Monika Fracz.k Nataliya Huleyuk Vyacheslav B chernykh Danuta z.stavna jan Barcisz.wski Maciej Kurpisz Department of Reproductive Biology and Stem Cells Institute of Human Genetics Polish Academy of Sciences Strzeszynska 32 60-479 Poznan Poland Department of RNA Biology Institute of Bioorganic Chemistry Polish Academy of Sciences Noskowskiego 12/14 61-704 Poznan Poland Institute of Hereditary Pathology Ukrainian Academy of Medical Sciences Lysenko Street 31a 79000 Lviv Ukraine Research Centre for Medical Genetics Russian Academy of Medical Sciences Moskvorechie Street 1115478 Moscow Russian Federation.

Male infertility might be clearly associated with aberrant DNA methylation patterns in human spermatoz.a. An association between oxidative stress and the global methylation status of the sperm genome has also been suggested. The aim of the present study was to determine whether the global sperm DNA methylation status was affected in the spermatoz.a of carriers of chromosome structural aberrations. The relationships between the 5-methylcytosine （msC） levels in spermatoz.a and chromatin integrity status were evaluated. The study patients comprised male carriers of chromosome structural aberrations with reproductive failure （n = 24）, and the controls comprised normoz.ospermic sperm volunteers （n = 23）. The global msC level was measured using thin-layer chromatography （TLC） and immunofluorescence （IF） techniques. The sperm chromatin integrity was assessed using aniline blue （AB） staining and TUNEL assay. The mean msC levels were similar between the investigated chromosome structural aberrations carriers （P） and controls （K）. However, sperm chromatin integrity tests revealed significantly higher values in chromosomal rearrangement carriers than in controls （P 〈 0.05）. Although the potential relationship between sperm chromatin integrity status and sperm DNA fragmentation and the msC level juxtaposed in both analyz.d groups （P vs K） was represented in a clearly opposite manner, the low chromatin integrity might be associated with the high hypomethylation status of the sperm DNA observed in carriers of chromosome structural aberrations.

关键词： 5-methylcytosine chromatin integrity chromosomal rearrangement chromosome translocation global DNA methylation male infertility

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