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Juvenile survival curves in a solitary ground squirrel with a prolonged hibernation:effects of individual characteristics,environment,and maternal investment

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Current Zoology 2024年第1期70卷 13-23页

作者： Nina A.Vasilieva Liudmila e Savinetskaya Andrey V.Tchabovsky A.N.Severtsov Institute of ecology and evolution Russian Academy of SciencesMoscow 119071Russia

Juvenile survival is a key life-history influence on population dynamics and adaptive *** analyzed the effects of individual chara-cteristics,early environment,and maternal investment on juvenile survival in a large solitary hibernating rodent-yellow ground squirrel Spermophilus fulvus using Cox mixed-effects *** 48%of weaned pups survived to dispersal and 17%survived to *** life expectancy was primarily de.e.mined by individual characteristics and,to a lesser extent,by the early *** strongest and pos-itive predictor of juvenile survival was body mass which crucially affected mortality immediately after *** suffered higher mortality than females after the onset of dispersal;however,the overall difference between sexes was partly masked by high rates of mortality in the first days after emergence in both *** emerged juveniles had lower life expectancy than the earliest *** overall effect of local juvenile density was *** lactation did not enhance juvenile survival:Pups nursed longer survived shorter than the young nursed for a shorter *** findings support the hypothesis that females of *** cannot effectively regulate maternal expenditures to mitigate the effects of unfavorable conditions on their *** strategy to deal with seasonal time constraints on life history in female *** suggests an early termination of maternal care at the cost of juvenile quality and *** female reproductive strategy corresponds to a"fast-solitary"life of folivorous de.e.t-dwelling *** and other solitary ground squirrels with prolonged hibernation.

关键词： early-life conditions ground squirrels hibernation juvenile mortality maternal investment survival curves

STUDy ON THe PROPeRTIeS OF BLeND OF NATURAL RUBBeR LATeX/MeTHyL MeTHACRyLATe GRAFTeD RUBBeR LATeX By GAMMA RADIATION

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Chinese Journal of Polymer Science 2007年第5期25卷 519-523页

作者： N.C. Dafader M.e. Haque F. Akhtar Nuclear and Radiation Chemistry Division Institute of Nuclear Science ＆ Technology Bangladesh Atomic Energy Commission P. O. Box 3787 Dhaka Bangladesh

Natural rubber latex （NRL） and methyl methacrylate （MMA） grafted rubber latex were blended in different ratios and irradiated at various absorbed doses by gamma rays from Co-60 source at room temperature. The tensile properties, swelling ratio and permanent set were measured. The maximum tensile strength and modulus at 500% elongation were obtained at an absorbed dose of 8 kGy. Modulus increases from 6.99 MPa to 9.87 MPa for an increase in proportion of MMA grafted rubber from 40% to 60% in the blend at similar absorbed dose. elongation at break and swelling ratio decrease with increasing absorbed dose as well as the MMA grafted rubber content in the blends. The decreasing trend of permanent set is high up to 5 kGy absorbed dose, and beyond that dose, it becomes almost flat.

关键词： Natural rubber latex MMA grafted rubber latex Blend rubber Irradiation Cross-link.

Bearing capacity and settlement of strip footing on geosynthetic reinforced clayey slopes

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Journal of Central South University 2012年第4期19卷 1116-1124页

作者： S.A.Naeini B.Khadem Rabe e.Mahmoodi department of Civil engineering Imam Khomeini International UniversityQazvin 16818-34149Iran

The effect of geosynthetic reinforcing on bearing capacity of a strip footing resting on georeinforced clayey slopes was *** results of a series of numerical study using finite element analyses on strip footing upon both reinforced and unreinforced clayey slopes were *** objectives of this work are to:1) de.e.mine the influence of reinforcement on the bearing-capacity of the strip footings adjacent slopes,2) suggest an optimum number of reinforcement and 3) survey the effect of friction angle in clayey soils reinforced by *** investigations were carried out by varying the edge distance of the footing from *** different numbers of geosynthetic layers were applied to obtaining the maximum bearing capacity and minimum *** achieve the third objective,two different friction angles were *** results show that the load?settlement behavior and ultimate bearing capacity of footing can be considerably improved by the inclusion of reinforcing *** using more than one layer reinforcement,the ultimate bearing capacity does not change *** is also shown that for both reinforced and unreinforced slopes,the bearing capacity increases with an increase in edge *** addition,as the soil friction angle is increased,the efficiency of reinforcing reduces.

关键词： geosynthetic reinforcing numerical analysis bearing capacity strip footing clayey slope friction angle

Journey Through the Groan Zone with Academics and Practitioners: Bridging Conflict and Difference to Strengthen Disaster Risk Reduction and Recovery Work

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International Journal of Disaster Risk Science 2018年第3期9卷 421-428页

作者： Katherine e.Browne Caela O'Connell Laura Meitzner yoder department of Anthropology Colorado State University department of Anthropology – Disasters Displacement and Human Rights Program University of Tennessee Program in Human needs and Global Resources Wheaton College

Academic-practitioner divides in disaster management and research can be persistent and pernicious,bearing consequences for disaster survivors and future affected populations. The gap between disaster professionals and academic researchers is often treated as an unavoidable structural problem or a neutral accident of professional silos and circumstance. We suggest that these gaps are not neutral, and that they can and must be overcome. With hundreds of millions of people affected by disaster each year and recovery costs skyrocketing, there is urgency in connecting researcher and practitioner knowledges to avoid expensive mistakes and most importantly, to decrease human suffering. yet the difficulties that US academic anthropologists and practitioners experienced in their efforts to collaborate became evident in a cross-sector National Science Foundation(NSF)-funded workshop on the relevance of culture in disaster work. We suggest and illustrate how more systematic cross-field communication can be operationalized through engaging in an ongoing and relational process of bridging. Such a process can offer long-term benefits to the people and institutions involved,dramatically enhance the science of disaster management,and help reduce the social and material costs of disaster impacts.

关键词： Academic and practitioner divide Applied research Cross-sector communication Culture and disaster Disaster anthropology Disaster management

A rapid and cost effective protocol for plant genomic DNA isolation using regenerated silica columns in combination with CTAB extraction

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Journal of Integrative Agriculture 2017年第8期16卷 1682-1688页

作者： FU Ze-yu SONG Jian-cheng Paula e.Jameson School of Biological Sciences University of Canterbury School of Life Sciences Yantai University

Isolation of high quality DNA from multiple samples can be both time-consuming and expensive. We have de.e.oped a combined protocol to reduce the time component of the hexadecyltrimethylammonium bromide （CTAB） extraction method and reduced costs by regenerating the silica columns used to purify genomic DNA. We present data that shows, by in- creasing the temperature used during the CTAB method, the time required to extract crude genomic DNA can be reduced. We show that silica columns can be regenerated using HCI and still maintain their DNA-binding capacity. Furthermore, we show both spectrophotometrically, and by restriction enzyme cutting, that the quality of the eluted DNA is high. Critically, using both genomic DNA from pea and perennial ryegrass we demonstrate, using species-specific PCR primers, that there is no carry-over of DNA from repeated use of a single column. The main advantages of the method are high yield, high quality, cost effectiveness and time-saving. This method could satisfy demand when large numbers of plant genomic DNA samples are required, for example from targeting induced local lesions in genomes （TILLING） populations.

关键词： CTAB DNA isolation silica columns

Antioxidative effect of melatonin, ascorbic acid and N-acetylcysteine on caerulein-induced pancreatitis and associated liver injury in rats

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World Journal of Gastroenterology 2006年第2期12卷 259-264页

作者： Mukaddes e■refoglu Mehmet Gül Burhan Ate■ Kadir Batoglu Mukadder Ay■e Selimoglu department of Histology and embryology Faculty of MedicineInonu University44280MalatyaTurkey department of Chemistry Faculty of Science and ArtInonu University44280MalatyaTurkey department of Biochemistry Faculty of PharmacyInonu University44280MalatyaTurkey department of Pediatric Gastroenterology Hepatology and NitrutionFaculty of MedicineAtaturk UniversityErzurumTurkey

AIM： To investigate the role of oxidative injury in pancreatitis-induced hepatic damage and the effect of antioxidant agents such as melatonin, ascorbic acid and N-acetyl cysteine on caerulein-induced pancreatitis and associated liver injury in rats. MeTHODS： Thirty-eight female Wistar rats were used. Acute pancreatitis （AP） was induced by two i.p. injections of caerulein at 2-h intervals （at a total dose of 100 μg/kg ***）. The other two groups received additional melatonin （20 mg/kg ***） or an antioxidant mixture containing L（＋）-ascorbic acid （14.3 mg/***.） and N-acetyl cysteine （181 mg/kg ***.） i.p. shortly before each injection of caerulein. The rats were sacrificed by decapitation 12 h after the last injection of caerulein. Pancreatic and hepatic oxidative stress markers were evaluated by changes in the amount of lipid peroxides measured as malondialdehyde （MDA） and changes in tissue antioxidant enzyme levels, catalase （CAT） and glutathione peroxidase （GPx）. Histopathological examination was performed using scoring systems. ReSULTS： The degree of hepatic cell de.e.eration, intracellular vacuolization, vascular congestion, sinusoidal dilatation and inflammatory infiltration showed a significant difference between caerulein and caerulein＋melatonin （P= 0.001）, and careulein and caerulein ＋ L（＋）- ascorbic acid ＋N-acetyl cysteine groups （P= 0.002）. The degree of aciner cell de.e.eration, pancreatic edema, intracellular vacuolization and inflammatory infiltration showed a significant difference between caerulein and caerulein ＋ melatonin （P=0.004）, and careulein and caerulein ＋ L（＋）-ascorbic acid ＋N-acetyl cysteine groups （P=0.002）. Caerulein-induced pancreatic and liver damage was accompanied with a significant increase in tissue MDA levels （P= 0.01, P= 0.003, respectively） whereas a significant decrease in CAT （P= 0.002, P=0.003, respectively） and GPx activities （P= 0.002, P= 0.03, respectively）. Melatonin and L（＋）-ascorbic acid ＋N-acetyl cysteine administratio

关键词： Caerulein Liver Melatonin Oxidative stress Pancreatitis

Phenotypic plasticity is maintained despite geographical isolation in an African cichlid fish,Pseudocrenilabrus multicolor

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Integrative Zoology 2014年第1期9卷 85-96页

作者： Kirsten e.WIeNS erika CRISPO Lauren J.CHAPMAN department of Pathology New York University School of MedicineNew YorkNYUSA department of Biology and Health Sciences Pace UniversityNew YorkNYUSA department of Biology McGill UniversityMontrealQuebecCanada Wildlife Conservation Society BronxNew YorkUSA

Gene flow among populations in different selective environments should favor the evolution of phenotypic plasticity over local *** in de.e.opment is a common response to long-term hypoxia in some widespread African fishes,including Pseudocrenilabrus multicolor,a cichlid that exploits both normoxic(high oxygen)rivers/lakes and hypoxic(low oxygen)*** studies have shown that fish from normoxic and hypoxic sites differ in many traits,including gill size,brain size and body shape,and that much of this vari-ation reflects de.e.opmental ***,these earlier studies focused on areas in Uganda where gene flow between swamp and river or lake populations is *** this study we tested the hypothesis that ***-color from a relatively isolated lake population(Lake Saka,Uganda)exhibit low levels of plasticity in traits re-lated to oxygen *** broods of *** from Lake Saka were reared under low and high dis-solved oxygen,and traits related to gill size,brain mass and body shape were ***,both gill size and brain mass showed high levels of de.e.opmental *** suggest that high levels of plasticity,particularly in the gill size of ***,reflects low costs of maintaining the plastic response,even in rela-tively isolated populations.

关键词： brain geometric morphometrics gills hypoxia riverine fish

An Automatic Optimization Technique for the Calibration of a Physically Based Hydrological Rainfall-Runoff Model

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Journal of Geoscience and environment Protection 2021年第3期9卷 1-20页

作者： Zohou Pierre Jérôme Alamou Adéchina eric Obada ezéchiel Biao Iboukoun eliézer eugène C. ezin Université d’Abomey-Calavi (UAC) Abomey-Calavi Bénin Laboratoire de Recherche en Sciences Informatiques et Applications (LRSIA) UAC Abomey-Calavi Bénin Laboratoire d’Hydrologie Appliquée (LHA) UAC Abomey-Calavi Bénin Université Nationale des Sciences Technologies Ingénierie et Mathématiques (UNSTIM) Abomey Bénin

Models are tools widely used in the prediction of hydrological phenomena. The present study aims to contribute to the implementation of an automatic optimization strategy of parameters for the calibration of a hydrological model based on the least action principle (HyMoLAP). The Downhill Simplex method is also known as the nelder-Mead algorithm, which is a heuristic research method, is used to optimize the cost function on a given domain. The performance of the model is evaluated by the Nash Stucliffe efficiency Index (NSe), the Root Mean Square error (RMSe), the coefficient of de.e.mination (R2), the Mean Absolute error (MAe). A comparative estimation is conducted using the Nash-Sutcliffe Modeling efficiency Index and the mean relative error to evaluate the performance of the optimization method. It appears that the variation in water balance parameter values is acceptable. The simulated optimization method appears to be the best in terms of lower variability of parameter values during successive tests. The quality of the parameter sets obtained is good enough to impact the performance of the objective functions in a minimum number of iterations. We have analyzed the algorithm from a technical point of view, and we have carried out an experimental comparison between specific factors such as the model structure and the parameter’s values. The results obtained confirm the quality of the model (NSe = 0.90 and 0.75 respectively in calibration and validation) and allow us to evaluate the efficiency of the nelder-Mead algorithm in the automatic calibration of the HyMoLAP model. The de.e.oped hybrid automatic calibration approach is therefore one of the promising ways to reduce computational time in rainfall-runoff modeling.

关键词： Optimization HyMoLAP Automatic Calibration Validation nelder-Mead Algorithm

Synthesis of LDHs and Rheological Properties of Laponite/LDHs Dispersions

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Chinese Chemical Letters 2003年第9期14卷 973-976页

作者： Pei Zhi GUO, de Jun SUN, Jie ZHANGkey Laboratory for Colloid & Interface Chemistry of education Ministry, Shandong University, Jinan 250100 key Lab. Colloid/Interface Chem. e. Shandong University Jinan 250100 China

The chemical composition, morphology of the particles of positively charged layered doubl?hydroxides (LDHs) were studied by ICP, Mastersizer, TeM. The preliminary results indicated that with adding LDHs to 1% laponite dispersion the yield stress of laponite/LDHs mixed dispersions increased at first, then decreased dramatically to a minimum, and the yield stress rose again when LDHs increased further.

关键词： Laponite layered double hydroxide rheological properties.