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Like mother, like daughter： heritability of female richardson＇s ground squirrel Urocitellus richardsonii cortisol stress responses

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Current Zoology 2018年第2期64卷 153-163页

作者： Kevin r. BAIrOS-NOVAK Calen r rYAN Angela r. FreeMAN W. gary ANDerSON James F, HAre Department of Biological Sciences University of Manitoba Winnipeg Manitoba R3T 2N2 Canada Departmentof Biology University of Saskatchewan Saskatoon S7N 5E2 Saskatchewan Canada Department ofAnthropology Northwestern University Evanston 60208 Illinois USA Department of Biological Sciences Kent State University Kent 44242 Ohio USA

Activation of the hypothalamic-pituitary-adrenal （HPA） axis liberates glucocorticoids, which provides an acute indication of an individual＇s response to stressors. The heritability of the stress response in wild mammals, however, remains poorly documented. We quantified the cortisol stress response of female richardson＇s ground squirrels （rGSs） to handling and physical restraint, testing for：（1） the effects of individual age, time of day, and sample latency; （2） repeatability within individuals; （3） narrow-sense heritability; and （4） differences among individuals owing to potential genetic and/or environmental effects. We detected a positive linear relationship between baseline plasma cortisol （BL-cortisol） concentration and stress-induced plasma cortisol （Sl-cortisol） concentration that defined each individual＇s cortisol stress response. BL-cortisol, SI-cortisol, and stress response did not differ according to the time the sample was taken, or by subject age. Cortisol stress response was highly repeatable within individuals, had a mother-offspring heritability of h2 =0.40 ± 0.24 （mean ±Se）, full-sibling heritability of h2s = 0.37 ± 0.71, and half-sibling heritabil- ity of hHS^2 = 0.75 ± 1.41. Stress responses of sibling groups, immediate-family groups, and squir- rels within a given area did not differ, whereas those of individuals from more distantly related matrilines did. Our results highlight the natural variability in HPA axis reactivity among individuals by quantifying both BL- and SI-cortisol levels, demonstrate partial heritability of the stress response that is not attributable to environmental variation, and suggest that at least part of an indi- vidual＇s stress response can be accounted for by differences in matrilineal history.

关键词： glucocorticoids ground squirrel heritability hypothalamic-pituitary-adrenal axis reactivity stress response.

Alternative models for transgenerational epigenetic inheritance:Molecular psychiatry beyond mice and man

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World Journal of Psychiatry 2021年第10期11卷 711-735页

作者： gary r Hime Sophie LA Stonehouse terence Y Pang Department of Anatomy and Physiology The University of MelbourneParkville 3010VICAustralia Mental Health Theme The Florey Institute of Neuroscience and Mental HealthParkville 3052VICAustralia

Mental illness remains the greatest chronic health burden globally with few inroads having been made despite significant advances in genomic knowledge in recent *** field of psychiatry is constantly challenged to bring new approaches and tools to address and treat the needs of vulnerable individuals and subpopulations,and that has to be supported by a continuous growth in *** majority of neuropsychiatric symptoms reflect complex geneenvironment interactions,with epigenetics bridging the gap between genetic susceptibility and environmental stressors that trigger disease onset and drive the advancement of *** has more recently been demonstrated in preclinical models that epigenetics underpins the transgenerational inheritance of stressrelated behavioural phenotypes in both paternal and maternal lineages,providing further supporting evidence for heritability in ***,unbiased prospective studies of this nature are practically impossible to conduct in humans so preclinical models remain our best option for researching the molecular pathophysiologies underlying many neuropsychiatric *** rodents will remain the dominant model system for preclinical studies(especially for addressing complex behavioural phenotypes),there is scope to expand current research of the molecular and epigenetic pathologies by using invertebrate ***,we will discuss the utility and advantages of two alternative model organisms–Caenorhabditis elegans and Drosophila melanogaster-and summarise the compelling insights of the epigenetic regulation of transgenerational inheritance that are potentially relevant to human psychiatry.

关键词： Transgenerational inheritance epigenetics Invertebrate models Caenorhabditis elegans Drosophila melanogaster environmental stress

Accuracy and safety of partial thickness femtosecond laser radial and arcuate keratotomy incisions in porcine eyes

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eye and Vision 2021年第1期8卷 412-421页

作者： e.Valas teuma Frank A.Bucci Jr raman Bedi gary Gray Mark Packer LeNSAr Inc.OrlandoFLUSA Bucci Laser Vision Institute Wilkes-BarreWilkes‑BarrePAUSA IrisArC ChandigarhIndia Packer research Associates Inc.1400 Bluebell Ave.BoulderCO 80302USA

Background:To evaluate the accuracy and safety of micro radial and arcuate keratotomy incisions constructed by a femtosecond laser system with a curved contact patient interface in porcine ***:Partial thickness micro radial and arcuate keratotomy incisions were constructed in porcine eyes with a femtosecond laser system and evaluated for precision of depth,quality,and *** coherence tomography was used to determine the accuracy and precision of incision *** endothelial safety was assessed by a fluorescent live/dead cell viability assay to demonstrate laser-induced endothelial cell *** was evaluated by ease of opening and examination of ***:In two micro radial incision groups,intended incision depths of 50%and 80%resulted in mean achieved depths of 50.01%and 77.69%,*** three arcuate incision groups,intended incision depths of 80%,600μm or 100μm residual uncut bed thickness resulted in mean achieved depths of 80.16%,603.03μm and residual bed of 115μm,*** loss of endothelial cell density occurred when the residual corneal bed was maintained at a minimum of 85-116μ*** incisions were easy to open,and interfaces were ***:A femtosecond laser system with curved contact interface created precise and reproducible micro radial and arcuate keratotomy *** and precision of the incision depth and preservation of endothelial cell density demonstrated the effectiveness and safety of the system.

关键词： Partial thickness micro radial and arcuate keratotomy incisions Curved contact patient interface Micro radial keratotomy Arcuate keratotomy Femtosecond laser system with curved contact interface LeNSAr femtosecond laser system

reliable Space Pursuing for reliability-based Design Optimization with Black-box Performance Functions

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Chinese Journal of Mechanical engineering 2009年第1期22卷 27-35页

作者： SHAN Songqing WANG G gary Department of Mech. and Manufacturing engineering the University of Manitoba Winnipeg MB R3T 5 V6 Canada School of engineering Science Simon Fraser University Surrey BC V3T OA3 Canada

reliability-based design optimization （rBDO） is intrinsically a double-loop procedure since it involves an overall optimization and an iterative reliability assessment at each search point. Due to the double-loop procedure, the computational expense of rBDO is normally very high. Current rBDO research focuses on problems with explicitly expressed performance functions and readily available gradients. This paper addresses a more challenging type of rBDO problem in which the performance functions are computation intensive. These computation intensive functions are often considered as a ＂black-box＂ and their gradients are not available or not reliable. On the basis of the reliable design space （rDS） concept proposed earlier by the authors, this paper proposes a reliable Space Pursuing （rSP） approach, in which rDS is first identified and then gradually refined while optimization is performed. It fundamentally avoids the nested optimization and probabilistic assessment loop. Three well known rBDO problems from the literature are used for testing and demonstrating the effectiveness of the proposed rSP method.

关键词： reliability based design optimization black-box function reliable design space

Validation of a radioimmunoassay-based fecal corticosteroid assay for richardson＇s ground squirrels Urocitellus richardsonii and behavioural correlates of stress

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Current Zoology 2014年第5期60卷 591-601页

作者： James F. HAre Calen r rYAN Chris eNrIGHT Laura e. GArDINer Lindsay J SKYNer Charlene N. BerKVeNS W. gary ANDerSON Department of Biological Sciences University of Manitoba Winnipeg MB Canada R3T 2N2 Assiniboine Park Zoo Winnipeg MB Canada R3R 2N7 Present Address: School of Applied Science Bay of Plenty Polytechnic Tauranga 3112 New Zealand

We validated a radioimmunoassay-based method quantifying fecal glucocorticoid metabolites （FGMs） from captive male and female richardson＇s ground squirrels Urocitellus richardsonii. Blood samples were drawn to explore the correlation between plasma cortisol and FGM concentrations. We also injected groups of squirrels with normal saline （CTL; control）, adre- nocorticotropic hormone （ACTH; stimulating adrenal activity）, or dexamethasone （DeX; suppressing adrenal activity）. Potential correlations between stress and behaviour were explored through quantification of fecal pellet production and the intervention necessary to elicit defecation, as well as the behaviour of subjects in the context of handling. Changes in plasma cortisol concen- tration between capture （baseline）, and following handling （stress-induced） were also quantified for free-living squirrels. While glucocorticoid concentrations recovered from feces during our captive-animal study were not well correlated with plasma eortisol concentrations, and uncorrelated with defecation or behaviour, FGM concentrations did reflect the activation of the hypothalamic- pituitary-adrenal （HPA） axis. FGM concentrations increased significantly during initial captivity, but declined to baseline level as individuals acclimated to the novel environment. Injection of subjects with ACTH increased FGMs above baseline, confirming activation of the HPA axis. Plasma cortisol concentrations increased significantly with induced stress, indicating that capture and handling activated the glucocorticoid stress response even among previously handled, free-living subjects. Our findings validate a non-invasive tool that will afford new insight into the physiological processes underlying social, reproductive and antipredator behaviour of richardson＇s ground squirrels [Current Zoology 60 （5）： 591-601, 2014 ].

关键词： Stress Corticosteroids Fecal glucocorticoid metabolites radioimmunoassay richardson's ground squirrels

Chemodynamics of heavy metals in long-term contaminated soils:Metal speciation in soil solution

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Journal of environmental Sciences 2009年第11期21卷 1532-1540页

作者： Kwon-rae Kim gary Owens Centre for environmental risk Assessment and remediation University of South Australia Climate Change & Agroecology Division Department of Agricultural Environment National Academy of Agricultural Science

The concentration and speciation of heavy metals in soil solution isolated from long-term contaminated soils were investigated. The soil solution was extracted at 70% maximum water holding capacity （MWHC） after equilibration for 24 h. The free metal concentrations （Cd^2＋, Cu^2＋, Pb^2＋, and Zn^2＋） in soil solution were determined using the Donnan membrane technique （DMT）. Initially the DMT was validated using artificial solutions where the percentage of free metal ions were significantly correlated with the percentages predicted using MINteQA2. However, there was a significant difference between the absolute free ion concentrations predicted by MINteQA2 and the values determined by the DMT. This was due to the significant metal adsorption onto the cation exchange membrane used in the DMT with 20%, 28%, 44%, and 8% mass loss of the initial total concentration of Cd, Cu, Pb, and Zn in solution, respectively. This could result in a significant error in the determination of free metal ions when using DMT if no allowance for membrane cation adsorption was made. relative to the total soluble metal concentrations the amounts of free Cd^2＋（3%-52%） and Zn^2＋（11%-72%） in soil solutions were generally higher than those of Cu^2＋（0.2%-30%） and Pb^2＋（0.6%-10%）. Among the key soil solution properties, dissolved heavy metal concentrations were the most significant factor governing free metal ion concentrations. Soil solution pH showed only a weak relationship with free metal ion partitioning coefficients （Kp） and dissolved organic carbon did not show any significant influence on Kp.

关键词： Donnan membrane technique free metal ion heavy metals partitioning coefficient solubility speciation

Population structure and linkage disequilibrium in elite barley breeding germplasm from the United States

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第6期13卷 438-451页

作者： gary MUeHLBAUer Brian SteFFeNSON Department of Agronomy and Plant Genetics University of MinnesotaSt.PaulMN 55108USA Department of Plant Pathology University of MinnesotaSt.PaulMN 55108USA

Cultivated barley is known to have a complex population structure and extensive linkage disequilibrium (LD).To conduct robust association mapping (AM) studies of economically important traits in US barley breeding germplasm,population structure and LD decay were examined in a complete panel of US barley breeding germplasm (3840 lines) genotyped with 3072 single nucleotide polymorphisms (SNPs).Nine subpopulations (sp1 sp9) were identified by the program STrUCTUre and subsequently confirmed by principle component analysis (PCA).Out of the nine subpopulations,seven were very similar to the respective subpopulations identified by Hamblin et al.(2010) which were based on half of the germplasm and half of the SNP markers,but two subpopulations were found to be *** subpopulation was dominated by six-rowed spring lines from Utah State University (UT) and the other was composed of six-rowed spring lines from multiple breeding programs (USDA-ArS Aberdeen (AB),Busch Agricultural resources Inc.(BA),UT,and Washington State University (WA)).LD was found to decay across a range from 4.0 to 19.8 *** result indicates that the germplasm genotyped with 3072 SNPs would be robust for mapping and possibly identifying the causal polymorphisms contributing to disease resistance and perhaps other traits.

关键词： Association mapping (AM) Structure Linkage disequilibrium (LD)

Both transmural dispersion of repolarization and of refractoriness are poor predictors of arrhythmogenicity： a role for iCeB （QT/QrS）？

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Journal of Geriatric Cardiology 2016年第9期13卷 813-814页

作者： gary Tse Department of Medicine and Therapeutics Faculty of Medicine Chinese University of Hong Kong Hong Kong China.

We read the original article by Nuis, et al. and the reply by Dogan, et al. with great interest. Nuis, et al. examined whether transcatheter aortic valve implantation （TAVI） in patients suffering from severe aortic stenosis led to changes in corrected QT dispersion （cQTD）, previously used to predict arrhythmic risk. Dogan, et al. proposed that a different marker, transmural dispersion of repolariza- tion （TDr）, has better accuracy in risk prediction.

关键词： Depolarization excitation wavelength QT dispersion Transmural dispersion of repolarization Transmural dispersion of refractoriness QT/QrS

Novel conduction-repolarization indices for the stratification of arrhythmic risk

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Journal of Geriatric Cardiology 2016年第9期13卷 811-812页

作者： gary Tse Department of Medicine and Therapeutics Faculty of Medicine Chinese University of Hong Kong Hong Kong China.

Sudden cardiac death （SCD） affects approximately 800,000 individuals per annum globally. It is most frequently due to cardiac tachy-arrhythmias, which include mono-morphic or polymorphic ventricular tachycardia （VT）, torsade de pointes and ventricular fibrillation （VF）. risk stratification for SCD remains a challenging problem in clinical practice.

关键词： Conduction Depolarization QrS QT dispersion repolarization Transmural dispersion of repolarization Wavelength