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Selective footprints and genes relevant to cold adaptation and other phenotypic traits are unscrambled in the genomes of divergently selected chicken breeds 被引量:2
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作者 Michael N.Romanov Alexandra S.Abdelmanova +11 位作者 Vladimir I.Fisinin Elena A.Gladyr Natalia A.Volkova Olga A.Koshkina Andrey N.Rodionov Anastasia N.Vetokh Igor V.Gusev Dmitry V.Anshakov Olga I.Stanishevskaya Arsen V.Dotsev Darren K.Griffin Natalia A.Zinovieva 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第3期887-907,共21页
Background The genomes of worldwide poultry breeds divergently selected for performance and other phenotypic traits may also be affected by,and formed due to,past and current admixture events.Adaptation to diverse env... Background The genomes of worldwide poultry breeds divergently selected for performance and other phenotypic traits may also be affected by,and formed due to,past and current admixture events.Adaptation to diverse environments,including acclimation to harsh climatic conditions,has also left selection footprints in breed genomes.Results Using the Chicken 50K_CobbCons SNP chip,we genotyped four divergently selected breeds:two aboriginal,cold tolerant Ushanka and Orloff Mille Fleur,one egg-type Russian White subjected to artificial selection for cold tolerance,and one meat-type White Cornish.Signals of selective sweeps were determined in the studied breeds using three methods:(1)assessment of runs of homozygosity islands,(2)F_(ST) based population differential analysis,and(3)haplotype differentiation analysis.Genomic regions of true selection signatures were identified by two or more methods or in two or more breeds.In these regions,we detected 540 prioritized candidate genes supplemented them with those that occurred in one breed using one statistic and were suggested in other studies.Amongst them,SOX5,ME3,ZNF536,WWP1,RIPK2,OSGIN2,DECR1,TPO,PPARGC1A,BDNF,MSTN,and beta-keratin genes can be especially mentioned as candidates for cold adaptation.Epigenetic factors may be involved in regulating some of these important genes(e.g.,TPO and BDNF).Conclusion Based on a genome-wide scan,our findings can help dissect the genetic architecture underlying various phenotypic traits in chicken breeds.These include genes representing the sine qua non for adaptation to harsh environments.Cold tolerance in acclimated chicken breeds may be developed following one of few specific gene expression mechanisms or more than one overlapping response known in cold-exposed individuals,and this warrants further investigation. 展开更多
关键词 ACCLIMATION Adaptation Chicken breeds Cold tolerance divergent selection Genetic diversity Genomewide scan Phenotypic traits Selective sweeps
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Phenotypical and gene co-expression network analyses of seed shattering in divergent sorghum(Sorghum spp.)
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作者 Xin Xiao Mengjiao Zhu +6 位作者 Yishan Liu Jingru Zheng Yiping Cui Candong Xiong Jiangjiang Liu Jun Chen Hongwei Cai 《The Crop Journal》 SCIE CSCD 2023年第2期478-489,共12页
Sorghum[Sorghum bicolor(L.)Moench],a multipurpose C4 crop,is also a model species of the Poaceae family for plant research.During the process of domestication,the modification of seed dispersal mode is considered a ke... Sorghum[Sorghum bicolor(L.)Moench],a multipurpose C4 crop,is also a model species of the Poaceae family for plant research.During the process of domestication,the modification of seed dispersal mode is considered a key event,as the loss of seed shattering caused a significant increase in yield.In order to understand the seed shattering process in sorghum,we further studied eight previously identified divergent sorghum germplasm with different shattering degrees.We described their phenotypes in great detail,analyzed the histology of abscission zone,and conducted a gene co-expression analysis.We observed that the abscission layer of the most strong-shattering varieties began to differentiate before the 5-10 cm panicles development stage and was completely formed at flag leaf unfolding.The protective cells on the pedicels were also fully lignified by flowering.Through the weighted gene correlation network analysis(WGCNA),we mined for candidate genes involved in the abscission process at the heading stage.We found that these genes were mainly associated with such biological processes as hormone signal transmission(SORBI_3003G361300,SORBI_3006G216500,SORBI_3009G027800,SORBI_3007G077200),cell wall modification and degradation(SORBI_3002G205500,SORBI_3004G013800,SORBI_3010G022400,SORBI_3003G251800,SORBI_3003G254700,SORBI_3003G410800,SORBI_3009G162700,SORBI_3001G406700,SORBI_3004G042700,SORBI_3004G244600,SORBI_3001G099100),and lignin synthesis(SORBI_3004G220700,SORBI_3004G062500,SORBI_3010G214900,SORBI_3009G181800).Our study has provided candidate genes required for shedding for further study.We believe that function characterization of these genes may provide insight into our understanding of seed shattering process. 展开更多
关键词 divergent sorghum Seed shattering Abscission zone WGCNA
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Creative Problem-Solving and Music: Analyzing the Correlation between Music and Divergent Thinking Abilities
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作者 Aidan Kang 《Journal of Behavioral and Brain Science》 2023年第11期199-205,共7页
This research paper delves into the connection, between problem-solving and music. It’s a topic that has piqued the interest of scholars in fields, including science and neuroscience. The study explores how music can... This research paper delves into the connection, between problem-solving and music. It’s a topic that has piqued the interest of scholars in fields, including science and neuroscience. The study explores how music can influence our ability to think divergently which is an aspect of creative thinking. It builds upon advancements in methods to investigate the relationship between music and divergent thinking aiming to uncover potential correlations. Doing it offers insights into the interplay between artistic expression and cognitive innovation. This research combines an analysis of existing literature with data collected from a group of participants shedding light on how music impacts our capacity for creative thinking. It demonstrates that music plays a role as a catalyst, for stimulating and enhancing thinking abilities. 展开更多
关键词 DREAM COGNITIVE Creative Problem-Solving divergent Thinking Abilities
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Intensity Evolution of Zonal Shear Line over the Tibetan Plateau in Summer:A Perspective of Divergent and Rotational Kinetic Energies 被引量:2
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作者 Xiaohong BAO Xiuping YAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第7期1021-1033,共13页
Based on the ERA5 reanalysis datasets during 1980-2019,a total of eleven zonal shear lines(ZSLs)that caused heavy precipitation and lasted more than 60 hours over the Tibetan Plateau in summer are selected for composi... Based on the ERA5 reanalysis datasets during 1980-2019,a total of eleven zonal shear lines(ZSLs)that caused heavy precipitation and lasted more than 60 hours over the Tibetan Plateau in summer are selected for composite analysis.By decomposing the kinetic energy(K)near the ZSL into divergent and rotational kinetic energies(K_(D)and K_(R))and the kinetic energy of interaction between the divergent wind and the rotational wind(K_(R)D),the influence of the rotational and divergent winds on the evolution of the ZSL intensity is investigated from the perspective of K_(D)and K_(R).The main results are as follows.The ZSL is a comprehensive reflection of rotation and convergence.The intensity evolution of ZSL is essentially synchronized with those of K,K_(R),and K_(RD)but lags behind K_(D)by about three hours.The enhancement of K is mainly contributed by K_(R),which is governed by the conversion from K_(D)to K_(R).Furthermore,the increase in the conversion from K_(D)to K_(R)is controlled by the geostrophic effect term Af,which is determined by the joint enhancement of the zonal rotational and meridional divergent wind components(u_(R)and v_(D)).Therefore,the joint enhancement of u_(R)and v_(D)controls the increase of the ZSL intensity,leading to increased precipitation. 展开更多
关键词 zonal shear line over the Tibetan Plateau intensity evolution divergent and rotational kinetic energies joint action of the zonal rotational and meridional divergent wind components
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On the Variation of Divergent Flow: An Eddy-flux Form Equation Based on the Quasi-geostrophic Balance and Its Application 被引量:1
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作者 Shenming FU Jie CAO +1 位作者 Xingwen JIANG Jianhua SUN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第5期599-612,共14页
Based on basic equations in isobaric coordinates and the quasi-geostrophic balance,an eddy-flux form budget equation of the divergent wind has been derived. This newly derived budget equation has evident physical sign... Based on basic equations in isobaric coordinates and the quasi-geostrophic balance,an eddy-flux form budget equation of the divergent wind has been derived. This newly derived budget equation has evident physical significance. It can show the intensity of a weather system,the variation of its flow pattern,and the feedback effects from smaller-scale systems(eddy flows). The usefulness of this new budget equation is examined by calculating budgets for the strong divergent-wind centers associated with the South Asian high,and the strong divergence centers over the Tibetan Plateau,during summer(June–August) 2010. The results indicate that the South Asian high significantly interacts with eddy flows. Compared with effects from the mean flow(background circulation),the eddy flows’ feedback influences are of greater importance in determining the flow pattern of the South Asian high. Although the positive divergence centers over the Tibetan Plateau intensify through different mechanisms,certain similarities are also obvious. First,the effects from mean flow are dominant in the rapid intensification process of the positive divergence center. Second,an intense offsetting mechanism exists between the effects associated with the eddy flows’ horizontal component and the effects related to the eddy flows’ convection activities,which weakens the total effects of the eddy flows significantly. Finally,compared with the effects associated with the convection activities of the mean flow,the accumulated effects of the eddy flows’ convection activities may be more favorable for the enhancement of the positive-divergence centers. 展开更多
关键词 divergent wind quasi-geostrophic balance scale interactions South Asia high
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The Dynamical Effects of Divergent Wind on the Intraseasonal variabinty of the East Asian Circulation 被引量:1
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作者 宋玉成 黄荣辉 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1995年第3期259-272,共14页
In this paper, the dynamical effeCts of divergent wind on the intraseasonal variability of atmospheric circulationover East Asia are analyzed by using the function of Rossby-wave source and the energy exchanging funct... In this paper, the dynamical effeCts of divergent wind on the intraseasonal variability of atmospheric circulationover East Asia are analyzed by using the function of Rossby-wave source and the energy exchanging function between divergent component and rotahonal component of the flow.The results analyzed from the observed data show that the advection of voracity by divergent wind caused by theheating due to the monsoon rainfall in the south to the Yangals River and the strong convective activities around thePhilippines may play an important role in the northward jump of westerly jet stream during the seasonal transitionfrom sprillg circulation to summer circulahon over East Asia. Due to the northward movement of the advechon ofvorticity by the divergent willd, the energy transformation from divergent component into rotational component canbe caused over the Yellow River basin and Northwest China and will cause the intensification of the zonal flow there.Thus, the jet stream abruptly shifts northward to North China.Moreover, the analysed results also show that the advection of vorticity by divergent wind caused by the heatingdue to the strong convective activities around the Philippines also plays an important role in the intraseasonal variability of the circulation over East Asia during the seasonal transition from summer to winter. With the southward'movement of the advection of vorticity by the divergent wind, the energy transformation from divergent componentinto rotational comPOnent can be caused over East Asia, espeially over the Yangtze-Huaihe River basin. Therefore,the jet stream gradually moves southward from North China to the YangtZe River basin. 展开更多
关键词 divergent wind Rossby-wave source Exchanging function.
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The Physiological Response during Divergent Thinking 被引量:1
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作者 Gareth H. Loudon Gina M. Deininger 《Journal of Behavioral and Brain Science》 2016年第1期28-37,共10页
Our research studied the physiological response of participants during a creative task to investigate if a person’s psychophysiological state was correlated with divergent thinking performance. We used heart rate var... Our research studied the physiological response of participants during a creative task to investigate if a person’s psychophysiological state was correlated with divergent thinking performance. We used heart rate variability as our physiological measure. We asked 50 participants to perform a cognitive task that assessed their divergent thinking skills and recorded their heart rate and heart rate variability (HRV) before and during the task. Frequency domain analysis was performed on the HRV. The results showed that there was a significant negative correlation between log-transformed low frequency HRV power and the number of “divergent thinking” words generated. Our results suggest that a person’s psychophysiological state is correlated with their divergent thinking performance, and that attention and motivation may be important factors, however this needs further research. Our findings also suggest that being in a relaxed state before the start of a creative task is not a predictor of creative performance. 展开更多
关键词 CREATIVITY divergent Thinking Heart Rate Variability ATTENTION MOTIVATION
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Growth Performance of Larval and Juvenile Manila Clam(Ruditapes philippinarum) from Divergently Selected Individuals of a Full-Sib Family
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作者 HUO Zhongming LI Xiaotong +4 位作者 SUN Qian LI Yongren ZHANG Xuekai YAN Xiwu YANG Feng 《Journal of Ocean University of China》 SCIE CAS 2016年第6期1046-1050,共5页
Abstract In this study, the method of divergent selection was employed to test the larval and juvenile growth performance within a full-sib family of Manila clam Ruditapes philippinarum. The 10% largest and 10% smalle... Abstract In this study, the method of divergent selection was employed to test the larval and juvenile growth performance within a full-sib family of Manila clam Ruditapes philippinarum. The 10% largest and 10% smallest clam individuals (on the basis of shell length) of a full-sib family were selected as parents for the fast and slow growing lines, respectively. The difference in shell length was significant among the three lines (fast, control, and slow) tested. The sequence of shell length were fast line 〉 control line 〉 slow line. The responses to selection, realized heritability, and genetic gain were 0.06%-0.81%, 0.04%-0.47% and 0.58%-18.89% in the fast direction, respectively; and were 0.14%-1.27%, 0.08%-0.73%, and 0.31%-49.03% in the slow direction, respectively. The re- suits suggested that there was a large portion of additive genetic variance affecting the growth in the full-sib family. Selection in the fast direction within the full-sib family would greatly improve the growth ofR. philippinarum. 展开更多
关键词 divergent selection full-sib family Manila clam
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System Position and Divergent Time of Based on ITS Sequence <i>Humulus scandens</i>
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作者 Renfang Chen Zehua Zhang +5 位作者 Weiting Sun Yun Fu Quncai Zhang Liang Wei Yanmei Liang Ruocheng Dong 《American Journal of Plant Sciences》 2012年第10期1470-1475,共6页
This article mainly studied Humulus scandens’ ITS sequence, its system position and its divergent time. ITS is 624 bp with a GC percentage content of 57.21%. It only has the variation in 585 (C changes T), systematic... This article mainly studied Humulus scandens’ ITS sequence, its system position and its divergent time. ITS is 624 bp with a GC percentage content of 57.21%. It only has the variation in 585 (C changes T), systematic position in Humulus lupulus (GenBank: EF136401) and Humulus scandens (GenBank: FJ980285), Humulus lupulus (GenBank: DQ005990), with Humulus scandens (GenBank: FJ980285), Humulus lupulus (GenBank: DQ005990) has the near sibship. Humulus in Moraceae family system position between Cudrania tricuspidata and Artocarpeae, support the Cannabiodeae promotion for Cannabinaceae. The divergent time of Humulus is 70.88 mya in Moraceae, Humulus scandens and Humulus lupulus (GenBank: EF136401) is 12.78 mya, with Humulus scandens (GenBank: FJ980285), Humulus lupulus (GenBank: DQ005990) is 1.10 mya. In the Moraceae branch’s molecular systematics research, the suitable choice is to choose Humulus scandens as Moraceae’s outgroup. 展开更多
关键词 MORACEAE HUMULUS scandens ITS Systematic POSITION divergent TIME
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Diffraction Properties of Blazed Gratings Illuminated with Broad-bandwidth and Divergent Beam
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作者 LIU Guo-hua LIU De-ming 《Semiconductor Photonics and Technology》 CAS 2008年第1期13-16,共4页
Far-field intensity and diffraction efficiency of the blazed reflection gratings illuminated with broad-bandwidth and divergent beam are investigated.When the spectral width and divergence of the incident beam with a ... Far-field intensity and diffraction efficiency of the blazed reflection gratings illuminated with broad-bandwidth and divergent beam are investigated.When the spectral width and divergence of the incident beam with a constant energy increase,the maximum intensity decreases,and the half width at e-2 of the maximum intensity becomes wider.Diffraction efficiency has no deterioration for the blazed grating with a proper groove shape even when the incident light contains a broad range of wavelengths and comes from a wide range of angles. 展开更多
关键词 blazed grating broad-bandwidth beam divergent beam fiber lasers
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A Variation Account of Divergent Thinking
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作者 Leonid Dorfman Vera Gassimova 《Journal of Literature and Art Studies》 2017年第8期1039-1053,共15页
A variation account was applied to divergent thinking accommodated as a kind of creative thinking. To provide control (contrast) condition the variation account was applied to psychometric intelligence. Guilford's ... A variation account was applied to divergent thinking accommodated as a kind of creative thinking. To provide control (contrast) condition the variation account was applied to psychometric intelligence. Guilford's (1956, 1967, 1988) theory of divergent-----convergent thinking served the background of our study. The main premise was that creative variation represents "thought trials" with diverse ways to find a solution to the problem. Task demands and the respective creative problem solving reveal advantageous sources that suggest the variation. Probably, uncertainty, information search, and finding alternatives extracted from memory precede, entail and provide variety of seeking, as well. A principal hypothesis to be tested was that divergent thinking enables its variation rather than intelligence does that to its variation. As predicted, the divergent thinking and its variation were related. Compared to uncreative, creative persons were characterized by larger variation. Apart from the mathematical intelligence, other kinds of intelligence and their variation did not correlate. Mainly, the data obtained, thus, lend support to the claimed hypothesis. 展开更多
关键词 VARIATION CREATIVITY divergent thinking INTELLIGENCE SCATTERING
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Combustion characteristics of low concentration coal mine methane in divergent porous media burner
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作者 Lin Baiquan Dai Huaming +3 位作者 Wang Chaoqun Li Qingzhao Wang Ke Zheng Yuanzhen 《International Journal of Mining Science and Technology》 SCIE EI 2014年第5期671-676,共6页
Low-concentration methane(LCM) has been one of the biggest difficulties in using coal mine methane.And previous studies found that premixed combustion in porous media is an effective method of low calorific gas utiliz... Low-concentration methane(LCM) has been one of the biggest difficulties in using coal mine methane.And previous studies found that premixed combustion in porous media is an effective method of low calorific gas utilization. This paper studied the combustion of LCM in a divergent porous medium burner(DPMB) by using computational fluid dynamics(CFD), and investigated the effect of gas initial temperature on combustion characteristic, the distribution of temperature and pollutant at different equivalence ratios in detail. Besides, the comparison of divergent and cylindrical burners was also performed in this paper. The results show that: the peak temperature in DPMB increases as the increasing of equivalence ratio, which is also suitable for the outlet NO discharge; the linear correlation is also discovered between peak temperature and equivalence ratios; NO emission at the initial temperature of 525 K is 5.64 times,larger than NO emission at the initial temperature of 300 K. Thus, it is preferable to balance the effect of thermal efficiency and environment simultaneously when determining the optimal initial temperature range. The working parameter limits of divergent burner are wider than that of cylindrical one which contributes to reducing the influence of LCM concentration and volume fluctuation on combustion. 展开更多
关键词 divergent porous media Low-concentration methane Premixed combustion Initial temperature
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NUMERICAL INVESTIGATION OF THREE-DIMENSIONAL VISCOUS INCOMPRESSIBLE FLOWS IN DIVERGENT CURVED CHANNELS AND TURBULENT MODEL STUDY
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作者 焦德勇 杨弘炜 +2 位作者 赵志君 苏杰先 冯国泰 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第7期639-646,共8页
In order to make the numerical calculation of viscous flows more convenient for the flows in channel with complicated profile governing equations expressed in the arbitrary curvilinear coordinates were derived by mean... In order to make the numerical calculation of viscous flows more convenient for the flows in channel with complicated profile governing equations expressed in the arbitrary curvilinear coordinates were derived by means of Favre density-weighted averaged method, and a turbulent model with effect of curvature modification was also derived. The numerical calculation of laminar and turbulent flown in divergent curved channels was carried out by means of parabolizeil computation method. The calculating results were used to analyze and investigate the aerodynamic performance of talor cascades in compressors preliminarily. 展开更多
关键词 NUMERICAL INVESTIGATION OF THREE-DIMENSIONAL VISCOUS INCOMPRESSIBLE FLOWS IN divergent CURVED CHANNELS AND TURBULENT MODEL STUDY
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A Novel Apprehension of the Primary Lung Meridian, Sinew Channel, Divergent Channel, Luo-Connecting Channel Acting as a Single Unit System to Serve Respiration Function Based on Modern Neurophysiology and Kinesiology
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作者 Peter Chin Wan Fung Regina Kit Chee Kong 《Chinese Medicine》 2020年第2期31-95,共65页
The TCM philosophy of a meridian and associated channels pertains to the specific function of one or more organs. We define the <span style="font-family:Verdana;">Lung Primary Meridian (LUM) together w... The TCM philosophy of a meridian and associated channels pertains to the specific function of one or more organs. We define the <span style="font-family:Verdana;">Lung Primary Meridian (LUM) together with the </span><span style="font-family:Verdana;">Lung Sinew (LUSC), Divergent (LUDC), Luo-connecting (LULCC) Channels as a system of routes plus some parts of the body (such as muscles) to fulfil respiration, as a main function under different situations. There is very limited information about the Lung associated channels in classical literature of TCM. With a clear focus on the function of respiration, we have carried out a detailed analysis of the biomedical consequence of stimulating the LUM, analysed the roles played by LUSC, LUDC, and LULCC. The updated LUM and LUDC include acupoints of other meridians, serving the same purpose of performing satisfactory respiration starting from checking the quality of the inflow through the nose. The LUSC includes the respiratory muscles (plus the associated connective tissues) extending to various parts of the body. The muscles of the limb (as part of the LUSC) embrace the nerves that provide routes for somatosensory reflexes and play the role of locomotion, providing voluntary respiration via the pectoralis muscles. The muscles of LUSC are bounded by stiff connective tissue layers, forming compartments, and are part of the pulley system for various body locomotions. Within a compartment, the interstitial fluid, blood, lymph flows must be potent to protect the associated nerves related to LUM;the healthy state of the LUSC also provides freedom of various types of locomotion. The LULCC exists because the vagus nerve has a part of it passing through the spinal cords all the way down to the sacrum domain, with exiting nerve innervating two-third of the large intestine. The crucial steps of our deductions </span><span style="font-family:Verdana;">are supported by experimental evidence based on modern neurophysiology and kinesiology. We discover that all the four channels stated above work as a unit system to allow respiration to be possible under various postures/conditions. </span><span style="font-family:Verdana;">The complexity of structures and processes is eased off by providing 29 figures and 13 tables for the relevant muscles and nerves. In addition to respiration, the Lung system in TCM context includes interaction of this system with the sweat gland and neuroendocrine system;such aspects will be left to another study.</span> 展开更多
关键词 Lung Meridian Sinew divergent Luo-Connecting Channels Mechanical Advantage of Muscles Sympathetic Nerves Parasympathetic Nerves Muscles of the Tongue PHARYNX Larynx Intercostal Muscles Inspiration and Expiration Muscles Swallowing Somatosensory and Segmental Reflexes Acupoints of the Lung Urinary Bladder Kidney Governing (DU) Conception (REN) Me-ridians Pulmonary Diseases Lung Large-Intestine Connection Acupuncture Bian Stone Therapy
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Positive Effects of Bilingualism: Divergent Thinking and Its Implications for Language Education
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作者 ZHENG Bing-jie 《海外英语》 2014年第22期284-287,共4页
The issue of bilingualism has been widely explored in the past decades,showing that there are multiple positive effects of"additive bilingualism".Such positive factors are closely linked with children’s cog... The issue of bilingualism has been widely explored in the past decades,showing that there are multiple positive effects of"additive bilingualism".Such positive factors are closely linked with children’s cognitive development and intelligence.This paper gives a detailed review on how bilingualism plays a role in children’s divergent thinking ability.Fully taking advantage of such positive effects in language education should be a significant part for bilingual education and foreign language programs.Thus,this paper further discusses the educational implications of these theoretic findings,suggesting that an additive bilingual environment should be cultivated through multiple ways of curriculum and program planning. 展开更多
关键词 BILINGUALISM divergent THINKING COGNITIVE developm
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Effect of Divergent Selection for Plasma very Low Denstity Lipoprotein Concentration on Reproductive Performance in Broiler Chickens
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作者 ChenJinwen ZhaoHeshan 《Journal of Northeast Agricultural University(English Edition)》 CAS 1998年第1期29-39,共11页
The reproductive performance and abdominal fat of the high VLDL (H-VLDL) and low VLDL (L-VLDL) lines were studied after divergent selection for plasma very low density lipoprotein (VLDL) concentration in broiler chick... The reproductive performance and abdominal fat of the high VLDL (H-VLDL) and low VLDL (L-VLDL) lines were studied after divergent selection for plasma very low density lipoprotein (VLDL) concentration in broiler chickens at 8 weeks of age. It was shown that the main reproductive traits were higher in L-VLDL line than H-VLDL line. The beneficial correlated responses of the reproductive traits were produced by the selection for plasma VLDL. 1) Plasma VLDL concentration was significantly correlated with abdominal fat (r=0.50, P<0.01), ahich was higher than that with plasma triglyceride concentration. There was a significant difference in abdominal fat between both lines but age increase or food restriction may decrease this difference. The H-VLDL line had about twice as much abdominal fat as had L-VLDL at 8 weeks of age, while its mean body weight was similar to that of the L-VLDL line from birtl to the end of laying. 2) Mortality from apparently stress-related causes by food restriction for H-VLDL line females began to increase from 15 weeks of age and was 21% (38/180) higher compared with 13% (23/180) for L-VLDL line females. 3) Age of 5% Lying for L-VLDL line was 3 days less than that of H-VLDL line, age of 50% Lying was 37 days less for L-VLDL line than H-VLDL line, and the age of laying peak was similiar in both lines. Rate of lay at peak in L-VLDL and H-VLDL lines were 70.3%, 66.4%, respectively. 4) Fertility rate in L-VLDL line was significantly higher than that of H-VLDL line at 27 weeks of age (P=0.01) and there was a little difference in fertility rates between H-VLDL and L-VLDL line during late laying period. There were no significant differences between H-VLDL and L-VLDL lines in of day-old healthy the numbers chicks and hatchabilities of fertile and total eggs wheres mean numbers of healthy day-old chicks per hen were more is L-VLDL line than in H-VLDL line. 5) Under food restriction, egg production was higher in L-VLDL line than in H-VLDL line. It should be emphasized that the rate and amount of egg production in L-VLDL line were both significant higher than in H-VLDL line during early laying period (from 23 to 43 weeks of age, P<0.01). The mean egg production of LF line hens was ll eggs more than that of HF line ones throughtout the laying period (from 23 to 62 weeks of age). 6) Eggs in L-VLDL line were slightly heavier than those in H-VLDL line. Feed conversion (FC) ratio for L-VLDL line was lower than that in H-VLDL line betwen 23 and 62 weeks of age (5.01 and 5.46, respectively), especially FC ratio of L-VLDL line was significantly lower than that of HF line during 23 and 43 weeks of age (P<0.01). Also FC efficiency of breeding hens was higher in L-VLDL line than in H-VLDL line. 展开更多
关键词 reproductive performance very low density lipoprotein divergent selection
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Divergent Synthesis of Organofluorinated Molecules from Titanium Mediated Deoxygenation of Free Alcohols 被引量:2
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作者 Hongjun Tian Ruifeng Zhang +2 位作者 Lei Shi Can Zha Xiaoming Wang 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2023年第15期1783-1790,共8页
Comprehensive Summary Alcohols as among the most widely occurring organic compounds known,deoxygenative transformations of free alcohols as partners in radical addition reactions remain formidable challenges with grea... Comprehensive Summary Alcohols as among the most widely occurring organic compounds known,deoxygenative transformations of free alcohols as partners in radical addition reactions remain formidable challenges with great opportunities to achieve new and useful transformations.Herein,we report a protocol via C—O bond cleavage and C—C bond-forming reaction of trifluoromethyl alkenes with free alcohols assisted by titanium reagents via a deoxygenative radical strategy,enabling the divergent synthesis for functional-group-rich organofluorinated compounds in high efficiencies.In this transformation,tertiary alcohols by Ti-catalysis could be converted to trifluoromethyl alkanes without defluorination in acidic conditions,while benzyl alcohols are employed by Ti-mediated activation to supply the gem-difluoroalkenes with defluorination in the presence of a base.This protocol is applicable for a broad range of trifluoromethyl alkenes with good functional group tolerance and a variety of tertiary alcohols and benzyl alcohols(including primary。 展开更多
关键词 divergent synthesis Organofluorinated compounds CROSS-COUPLING Titanium-mediated ALCOHOLS Radical
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Ni-catalyzed ligand-controlled divergent and selective synthesis
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作者 Yang Ke Wei Li +1 位作者 Wenfeng Liu Wangqing Kong 《Science China Chemistry》 SCIE EI CAS CSCD 2023年第11期2951-2976,共26页
Scaffold diversity is a key feature of a compound library and plays a pivotal role in its success in biological screening.Therefore,it is highly desirable to develop efficient strategies to rapidly construct structura... Scaffold diversity is a key feature of a compound library and plays a pivotal role in its success in biological screening.Therefore,it is highly desirable to develop efficient strategies to rapidly construct structurally distinct and diverse“privileged”molecular scaffolds,thereby giving rise to compound libraries with selective and differing biological activities.This review covers recent efforts in this emerging field of Ni-catalyzed divergent and selective synthesis,and will focus on reactions using the same substrate to generate structurally diverse molecular scaffolds by varying the ligand backbone under otherwise almost identical reaction conditions.We hope that the field will be encouraged by the progress achieved,drawing attention to the design and development of new selective catalytic systems,and revealing new modes of catalytic transformation for broader synthetic applications. 展开更多
关键词 nickel catalysis CHEMOSELECTIVITY regioselectivity STEREOSELECTIVITY divergent synthesis
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Divergent synthesis of aryl amines and dihydroquinazolinones via electrochemistry-enabled rhodium-catalyzed C–H functionalization
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作者 Yi-Kang Xing Zhen-Hua Wang +2 位作者 Ping Fang Cong Ma Tian-Sheng Mei 《Science China Chemistry》 SCIE EI CAS CSCD 2023年第10期2863-2870,共8页
Electrochemistry-enabled rhodium-catalyzed C–H amination and amination cyclization of arene assisted by a weakly coordinating amide have been reported. Additionally, aryl amines and dihydroquinazolinones could be obt... Electrochemistry-enabled rhodium-catalyzed C–H amination and amination cyclization of arene assisted by a weakly coordinating amide have been reported. Additionally, aryl amines and dihydroquinazolinones could be obtained selectively by controlling the electric current. Mechanistic studies suggested that the amination reaction likely involves an electrochemical oxidation-induced reductive elimination of a high valent rhodium intermediate, which led to the amination reaction even proceeding smoothly at room temperature. 展开更多
关键词 organic electrochemistry rhodium catalysis C-H functionalization divergent synthesis
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Study on direct point spread function measurement of capillary plate collimators with divergent X-ray beams
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作者 Tianming Li Tao Luo +2 位作者 Yupeng Xu Huilin He Liming Song 《Radiation Detection Technology and Methods》 CSCD 2023年第3期321-336,共16页
Purpose The Filed of View(FOV)of eXTP/LAD is limited by lead-glass capillary plate collimators placed in front of the Silicon Drift Detectors(SDDs)for reducing the background contamination caused by the photons of Cos... Purpose The Filed of View(FOV)of eXTP/LAD is limited by lead-glass capillary plate collimators placed in front of the Silicon Drift Detectors(SDDs)for reducing the background contamination caused by the photons of Cosmic X-ray Background(CXB)leaking from outside the FOV.The core quality parameters of lead-glass capillary plate collimators are Open Area Ratio(OAR)and FOV.The performance of lead-glass capillary plate collimators is determined by its design specification such as pore-to-pore misalignment,pore perpendicularity with collimator surface and pore diameter.Since the design specification is the result of a large number of micropores,we use the full width at half maximum(FWHM)and peak value of point spread function(PSF)to characterize the capillary plate collimator performance.In order to quickly evaluate the performances of collimators,we developed a direct PSF measurement method using divergent beams.Methods In this paper,the simulation package of the divergent beamsmeasurement setup is developed based on Geant4.The simulation parameters of scintillator absorption length are corrected by experimental data.We simulate the PSF of collimators with different distribution of pore diameter and misalignment by parallel beams and divergent beams.By comparing the peak value and FWHM of collimators PSF,the feasibility in replacing parallel beams measurement with divergent beams measurement is studied.Results It is verified that the influence of the geometric size of 33μm radius of the micro-focus of X-ray tube can be ignored.The results show that the FWHM of collimators is increased with error root mean square error(RMS)of the distribution of collimators pore diameter and pore inclination angle.The peak value of PSF is mainly influenced by pore non-parallelism of the pores,and it decreases with an increase in pore inclination angle.Comparison of parallel beams PSF and divergent beams PSF shows well consistency of peak value and FWHM of collimator.But,the peak value of the divergent beams PSF is mainly affected by the defects of the pores close to the optical axis and result in difference from the parallel beams results consequently.We have developed capillary plate collimators response function based on the projected area function of a cylindrical pore and the fluorescence broadening of the scintillator and fitted PSF by response function.The capillary plate collimator open area ratio is calculated by using the micropores radius and collimator frame thickness obtained by fitting parameter,and the result is close to the parallel beams PSF.Conclusion The feasibility divergent beams measurement is verified. 展开更多
关键词 GEANT4 EXTP/LAD Capillary plate collimators divergent X-ray beams measurment
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