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Preferential Bivalent Formation in Tetraploid Male of Pacific Oyster Crassostrea gigas Thunberg

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Journal of Ocean University of China 2014年第2期13卷 297-302页

作者： ZHANG Zhengrui WANG Xinglian ZHANG Quanqi Standish Allen jr. College of Marine Life Sciences Key Laboratory of Marine Genetics and Breeding of Ministry of EducationOcean University of China Aquaculture Genetics and Breeding Technology Center Virginia Institute of Marine ScienceCollege of William and Mary

Artificially induced tetraploid Pacific oyster, Crassostrea gigas Thunberg, produces more aneuploid gametes than normal diploid one, although they showed a comparable fecundity to diploidy. The meiotic chromosome configuration of 3 tetraploid and 1 tetraploid/triploid mosaic males were analyzed through direct chromosome observation. A majority of metaphase I spermatocytes contained both bivalents and quadrivalents. The chromosome configuration of these males was characterized by preferential formation of bivalents to quadrivalents. Bivalents appeared in all spermatocytes and consisted of 86% of all chromosome aggregates. In comparison, quadrivalents occurred in 91% spermatocytes and consisted of only 12.6% of all chromosome aggregates. The mean bivalent frequency per spermatocyte varied between 14.4 and 17.2; while that of quadrivalents varied between 2.2 and 2.7. Most quadrivalents were tandemly chained(58%) or circled(39%). The total number of chromosome aggregates per spermatocyte ranged from 13 to 20 with an average of 17.6; while 18(16 bivalents and 2 quadrivalents) was the most frequent. Univalents and trivalents appeared in very low frequency. Aneuploid(hypotetraploid) spermatocytes were observed in a low frequency. The chromosome configuration of in the mosaic individual was similar to that of tetraploid individuals. The percentage of triploid spermatocytes(2%) of the mosaic individual was significantly lower(χ2 =30, P < 0.01) than that of triploid cells(46%) in its somatic tissue.

关键词：太平洋牡蛎四倍体二价体优惠政策瓢虫长牡蛎染色体构型精母细胞

An Adaptive Sequential Replacement Method for Variable Selection in Linear Regression Analysis

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Open Journal of Statistics 2023年第5期13卷 746-760页

作者： Jixiang Wu Johnie N. Jenkins Jack C. McCarty jr. Genetics and Sustainable Agriculture Research Unit USDA-ARS Mississippi State USA

With the rapid development of DNA technologies, high throughput genomic data have become a powerful leverage to locate desirable genetic loci associated with traits of importance in various crop species. However, current genetic association mapping analyses are focused on identifying individual QTLs. This study aimed to identify a set of QTLs or genetic markers, which can capture genetic variability for marker-assisted selection. Selecting a set with k loci that can maximize genetic variation out of high throughput genomic data is a challenging issue. In this study, we proposed an adaptive sequential replacement (ASR) method, which is considered a variant of the sequential replacement (SR) method. Through Monte Carlo simulation and comparing with four other selection methods: exhaustive, SR method, forward, and backward methods we found that the ASR method sustains consistent and repeatable results comparable to the exhaustive method with much reduced computational intensity.

关键词： Adaptive Sequential Replacement Association Mapping Exhaustive Method Global Optimal Solution Sequential Replacement Variable Selection

Dynamic Instability of Straight Bars Subjected to Impulsive Axial Loads Using the DEM

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Computer Modeling in Engineering & Sciences 2015年第2期104卷 87-104页

作者： Leticia Fleck Fadel Miguel Leandro Fleck Fadel Miguel Joao Kaminski jr. Department of Mechanical Engineering UFRGSPorto AlegreRSBrazil Department of Civil Engineering UFSCFlorianopolisSCBrazil Department of Structures and Civil Construction UFSMSanta MariaRSBrazil

Since the half of the XX century,attention was given to the instability of structures under parametric excitation,especially under periodic *** the other hand,the instability of bars subjected to axial loads of impulsive type has been little studied,in spite of the practical importance of the ***,in Engineering Design it is frequently supposed,without tests or additional verifications,that an axial load of short duration can exceed the Euler critical load of the bar without inducing damage in the *** this context,this paper proposes the use of the truss-like Discrete Element Method(DEM)for determining the dynamic response of elastic straight bars subjected to axial loads defined by pulses of short *** proposed approach allows the consideration of initial imperfections,as well as large displacements and other non-linear *** influence of the pulse duration and other effects in the response of the bar are also ***,the performance of the proposed methodology is verified in static and dynamic instability problems of homogeneous bars without geometrical imperfections,by comparing the DEM results with analytical solutions available in the *** that,the DEM is employed to analyze more complex cases,including bars with initial imperfections and non-homogeneous bars,in which material properties,as Young’s modulus and mass density,are assumed to be correlated Gaussian random *** proposed methodology has proven to be a useful and easy tool for analysis of dynamic instability of bars and could therefore be used by designers for estimating the dynamic buckling load.

关键词： Dynamic Instability Critical Buckling Load Discrete Element Method Impulsive Load Stochastic Fields Mesh Imperfections

Assessing Cowpea-Wheat Double Cropping Strategies in the Southern United States Using the DSSAT Crop Model

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Agricultural Sciences 2022年第6期13卷 758-775页

作者： Prem Woli Gerald Ray Smith Charles Long Francis Monte Rouquette jr. Texas A&M AgriLife Research Center Overton Texas USA

Information is limited on the potential of cowpea-wheat double cropping in the southern United States to enhance soil health and increase net returns. Using the Decision Support System for Agrotechnology Transfer (DSSAT) crop model and weather data spanning 80 years, we assessed the effects of soil type (Darco: Grossarenic Paleudults and Lilbert: Arenic Plinthic Paleudults), N application rate (0, 100, and 200 kg•ha−1), and El Niño-Southern Oscillation (ENSO) on the grain yields of double-cropped cowpea (Vigna unguiculata L.) and wheat (Triticum aestivum L.) in this region. Yield differences were tested using the pairwise Wilcoxon rank sum test. Results showed that yields of wheat that followed cowpea (cwheat) were greater than those that followed fallow (fwheat). The soil type effects on cwheat and fwheat yields decreased with an increase in N rate. The soil type effect on cowpea yields was greater during La Niña. The ENSO impact on cowpea yields was greater on the less fertile soil Darco. Yields of cwheat and fwheat increased with an increase in N rate up to 100 and 200 kg•ha−1, respectively. The yield response of cwheat to N rate was less than that of fwheat. The N rate effects on cwheat and fwheat yields were greater on Darco and under El Niño. Yields of cowpea were greatest under El Niño, whereas those of wheat were greatest under La Niña. The ENSO effect on cowpea yields was greater on Darco. With an increase in N rate, the effect of ENSO was diminished.

关键词： Cowpea-Wheat DSSAT Double-Cropping ENSO Model

Polysubstance Use and Overdose Visualized via Maps: Opioids

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Pharmacology & Pharmacy 2022年第4期13卷 107-118页

作者： Robert B. Raffa Joseph V. Pergolizzi jr. Herm Cukier Temple University School of Pharmacy (Emeritus) Philadelphia PA USA University of Arizona College of Pharmacy (Adjunct) Tucson AZ USA Neumentum Summit NJ USA Enalare Therapeutics Princeton NJ USA NEMA Research Naples FL USA

Polysubstance (combinations of substances) abuse and overdose deaths now surpass mono-substance abuse and overdose deaths. Several international and governmental organizations such as the WHO (World Health Organization), CDC (Centers for Disease Control and Prevention), several of the Institutes of the NIH (National Institutes of Health), Regulators, and Enforcement Agencies, among others, track and provide a valuable source of statistical information about drug (prescription and illicit) (mis)use and overdose. The information is disseminated free to stakeholders and the general public for use. Although the numeric presentations of the data are helpful and adequate for professionals, the non-expert and the visual learner often find visual representation more clear and more compelling. With this in mind, the aim of this study was to present polysubstance use and overdose using visual maps of the available data. This article considers the opioids.

关键词： Polysubstance Use Disorder Overdose Maps Opioids

Polysubstance Use and Overdose Visualized via Maps: Amphetamines and Cocaine

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Pharmacology & Pharmacy 2022年第5期13卷 140-148页

作者： Robert B. Raffa Joseph V. Pergolizzi jr. Herm Cukier School of Pharmacy (Emeritus) Temple University Philadelphia PA USA University of Arizona College of Pharmacy (Adjunct) Tucson AZ USA Neumentum Summit NJ USA Enalare Therapeutics Princeton NJ USA NEMA Research Naples FL USA

Abuse of drug substances and resultant overdose deaths are no longer very straightforward—viz., attributable to a single chemical entity of known purity. The reality is that most overdose deaths involve polysubstance use (i.e., the use of combinations of substances). Further, the combinations are often of unknown purity, and even of unknown composition. Overdose deaths are at all-time highs. The depressing statistics are monitored and reported by several international and governmental organizations such as the WHO (World Health Organization), CDC (Centers for Disease Control and Prevention), several Institutes of the NIH (National Institutes of Health), Regulators, and Enforcement Agencies (e.g., DEA). The information is disseminated for free for review and use. But it is our observation that although numeric presentation is helpful and adequate for professionals, the non-expert and the visual learner often find a visual representation clearer and compelling. With this in mind, we present the “gestalt” of polysubstance use and overdose using available maps of the data. The previous article in the series considered the opioids. This one considers amphetamines and cocaine, and places the rise in opioid-associated overdose deaths in the context of other abused drugs.

关键词： Polysubstance Use/Abuse Use Disorder Overdose Maps Amphetamine Cocaine

Shape Selectivity of a Metallo Cavitand Host Allows Separation of n-Alkanes from Isooctane

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Chinese Journal of Chemistry 2021年第6期39卷 1498-1502页

作者： Yun-Hui Wan Faiz-Ur Rahman Julius Rebek jr. Yang Yu Center for Supramolecular Chemistry&Catalysis and Department of Chemistry College of ScienceShanghai University99 Shang-Da RoodShanghai 200444China Skaggs Institute for Chemical Biology and Department of Chemistry The Scripps Research Institute10550 North Torrey Pines Roadio JolloCA 92037USA

The use of a metallo cavitand for the selective sequestration of n-alkanes from their mixtures with isooctane is *** experiments and NMR spectroscopy are used to show the preference of a water-soluble cavitand host for guests that are hydro-phobic and have narrow or flat *** host showed selectivity for trans 1,4-dimethylcyclohexane over the *** sep-arations of n-alkanes from isooctane by gas/liquid adsorption and a liquid/liquid extraction are detailed.

关键词： Metallo cavitand Shape selectivity eceptor Alkane separation Host-guest system

Application of neurotrophic and proangiogenic factors as therapy after peripheral nervous system injury

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Neural Regeneration Research 2022年第6期17卷 1240-1247页

作者： Kamilla Faritovna Idrisova Alina Kazymovna Zeinalova Galina Andreevna Masgutova Alexey Andreevich Bogov jr. Cinzia Allegrucci Valeriia Yurievna Syromiatnikova Ilnur Ildusovich Salafutdinov Ekaterna Evgenievna Garanina Dina ivanovna Andreeva Adilet Abdullaatovich Kadyrov Albert Anatolevich Rizvanov Ruslan Faridovich Masgutov Institute of Fundamental Medicine and Biology Kazan Federal UniversityKazanRussia Republican Clinical Hospital KazanRussia Biodiscovery Institute School of Veterinary Medicine and ScienceUniversity of NottinghamNottinghamUK Department of Traumatology and Orthopedics Kazan State Medical AcademyKazanRussia

The intrinsic ability of peripheral nerves to regenerate after injury is extremely limited,especially in case of severe *** often leads to poor motor function and permanent *** approaches for the treatment of injured nerves do not provide appropriate conditions to support survival and growth of nerve *** drawback can be compensated by the use of gene therapy and cell therapy-based drugs that locally provide an increase in the key regulators of nerve growth,including neurotrophic factors and extracellular matrix *** growth factor plays its own specific angiotrophic or neurotrophic ***,growth factors are widely studied as accelerators of nerve *** noteworthy is synergy between various growth factors,that is essential for both angiogenesis and *** growth factor 2 and vascular endothelial growth factor are widely known for their proangiogenic *** the same time,fibroblast growth factor 2 and vascular endothelial growth factor stimulate neural cell growth and play an important role in neurodegenerative diseases of the peripheral nervous *** together,their neurotrophic and angiogenic properties have positive effect on the regeneration *** this review we provide an in-depth overview of the role of fibroblast growth factor 2 and vascular endothelial growth factor in the regeneration of peripheral nerves,thus demonstrating their neurotherapeutic efficacy in improving neuron survival in the peripheral nervous system.

关键词： fibroblast growth factor 2 growth factors nerve growth factor peripheral nerve injury peripheral nervous system vascular endothelial growth factor

Selectively breeding for high voluntary physical activity in female mice does not bestow inherent characteristics that resemble eccentric remodeling of the heart,but the mini-muscle phenotype does

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Sports Medicine and Health Science 2023年第3期5卷 205-212页

作者： Eric C.Leszczynski Nicole E.Schwartz Ashley C.McPeek Katharine D.Currie David P.Ferguson Theodore Garland jr. Department of Kinesiology Michigan State UniversityEast LansingMIUSA Department of Evolution Ecologyand Organismal BiologyUniversity of California RiversideRiversideCAUSA

Physical activity engagement results in a variety of positive health outcomes,including a reduction in cardiovascular disease risk partially due to eccentric remodeling of the *** purpose of this investigation was to determine if four replicate lines of High Runner mice that have been selectively bred for voluntary exercise on wheels have a cardiac phenotype that resembles the outcome of eccentric *** females(average age 55 days)from the 4 High Runner and 4 non-selected control lines were anaesthetized via vaporized isoflurane,then echocardiographic images were collected and analyzed for structural and functional *** Runner mice in general had lower ejection fractions compared to control mice lines(2-tailed p=0.0236)and tended to have thicker walls of the anterior portion of the left ventricle(p=0.065).However,a subset of the High Runner individuals,termed mini-muscle mice,had greater ejection fraction(p=0.0006),fractional shortening percentage(p<0.0001),and ventricular mass at dissection(p<0.0027 with body mass as a covariate)compared to non-mini muscle *** from replicate lines bred for high voluntary exercise did not all have inherent positive cardiac functional or structural characteristics,although a genetically unique subset of mini-muscle individuals did have greater functional cardiac characteristics,which in conjunction with their previously described peripheral aerobic enhancements(e.g.,increased capillarity)would partially account for their increased VO2max.

关键词： Echocardiography Heart Voluntary physical activity Cardiovascular disease Wheel running