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Short-span interleaving based selected mapping
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作者 吴炳洋 程时昕 《Journal of Southeast University(English Edition)》 EI CAS 2005年第4期385-388,共4页
A novel interleaving based selected mapping (SLM) scheme to depress the relatively high peak power of transmit signals in multicarrier communications is proposed. In the scheme, a group of bit-level interleavers spa... A novel interleaving based selected mapping (SLM) scheme to depress the relatively high peak power of transmit signals in multicarrier communications is proposed. In the scheme, a group of bit-level interleavers spanning only a few bits are used to produce multiple sequences representing the same information, and one of the sequences resulting in the lowest peak-to-average power ratio (PAPR) is selected for transmission. The implementation of the scheme including the structure of the short-span interleaver is illustrated. The performance of this PAPR reduction scheme is investigated by simulations. This scheme exhibits a good PAPR reduction performance, and for signals of high level modulation, such as 16QAM and 64QAM, it approaches the best performance of all SLM schemes. Compared to the conventional interleaving SLM, this short-span interleaving SLM results in a very short time delay, requires very few register units for buffering, and can be easily implemented by hardware. 展开更多
关键词 multicarrier communications peak-to-average power ratio selected mapping INTERLEAVING
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基于SELECT理念腹腔镜下保留脾脏的胰体尾切除
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作者 李爽 张标 +5 位作者 刘航宇 祁冰 Thomas Juby 张桂信 张庆凯 尚东 《临床外科杂志》 2024年第7期776-779,共4页
腹腔镜下胰体尾切除术目前已经成为治疗胰腺体尾部肿瘤的标准术式。而腹腔镜下保留脾脏的胰体尾切除术由于可保留脾脏功能,减少脾切除术后并发症,越来越受到重视。然而,胰腺肿瘤发病隐匿、解剖位置复杂,这些对其诊断和保留脾脏的胰体尾... 腹腔镜下胰体尾切除术目前已经成为治疗胰腺体尾部肿瘤的标准术式。而腹腔镜下保留脾脏的胰体尾切除术由于可保留脾脏功能,减少脾切除术后并发症,越来越受到重视。然而,胰腺肿瘤发病隐匿、解剖位置复杂,这些对其诊断和保留脾脏的胰体尾切除术带来了挑战。近年来,我们团队积累了丰富的胰腺肿瘤诊疗经验,创新提出“SELECT”(S-Single-Operator Cholangiopancreatoscopy,E-ERCP,L-Laparoscopy,E-Endoscopic ultrasound,C-Choledochoscopy/Confocal laser endomicroscopy,T-Traditional Chinese medicine)多镜组合中西医微创诊治理念。根据胰腺肿瘤的类型及特点,应用多种内镜和腹腔镜技术,多种不同微创诊疗方法的优选组合,围手术期采用中医药,进行中西医结合加速康复。将SELECT理念充分应用于腹腔镜下保留脾脏的胰体尾切除术,有利于术前精准诊断、术中精准切除、术后并发症预判和治疗,一站式诊治胰腺肿瘤,使病人利益最大化。 展开更多
关键词 select理念 多镜联合 胰腺肿瘤 保留脾脏 胰体尾切除术
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Growth performance and physiological parameters of the second generation selected and control groups of Pinctada martensii 被引量:10
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作者 DENG Yuewen YU Ziniu +2 位作者 DU Xiaodong WANG Qingheng FU Shao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2011年第2期120-125,共6页
In May of 2007,the second generation selected (SS) and control (SC) groups of pearl oyster Pinctada martensii were established by selecting 10% breeders with the largest and mean shell length,respectively,from the... In May of 2007,the second generation selected (SS) and control (SC) groups of pearl oyster Pinctada martensii were established by selecting 10% breeders with the largest and mean shell length,respectively,from the first generation selected group.Growth performance of the SS and SC groups were compared on the basis of measurement data at Days 8,18,60,95,195 and 365.On Day 365,100 individuals (60.0–75.0 mm at shell length) were sampled from each group and then subjected to the experiment where physiological parameters such as filtrate rate,oxygen consumption and ammonia excretion were measured at 15,20,25 and 30°C.The results show that the SS group had significantly larger mean shell length and shell height than the SC group at Days 8,18,60,95,195 and 365 (P 0.05).The genetic gains at different ages varied from 6.0% to 17.0% for shell length and 5.7% to 14.6% for shell height,respectively.At 15,20,25 and 30 ° C,the SS groups had significantly larger filtrate rate than the SC group (P 0.05).At 15 and 25 °C,the differences in oxygen consumption rate between the SS and SC groups were not significant (P 0.05).At 20 and 30 °C,however,the oxygen consumption rate of the SS group was significantly larger than the SC group (P 0.05).At 15,20,25 and 30 °C,there were no significant differences in ammonia excretion rate between the SS and SC groups (P 0.05).The present results indicate that there existed considerable genetic variability in the base population and a further selection could be likely fruitful.Mass selection for faster growth might produce animals that had higher intake of metabolizable energy by virtue of faster filtrating behavior. 展开更多
关键词 Pinctada martensii the second generation selected group GROWTH genetic gains physiological parameters
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The Power of Patronage Exercised in the Translation of Selected Works of Deng Xiaoping
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作者 韩媛媛 赵伟兴 《科技信息》 2010年第4期17-18,共2页
By referring to Lefevere’s theory of patronage, this paper examines the issue of patronage in the translation of Selected Works of Deng Xiaoping, a remarkable political work of our country. It addresses the questions... By referring to Lefevere’s theory of patronage, this paper examines the issue of patronage in the translation of Selected Works of Deng Xiaoping, a remarkable political work of our country. It addresses the questions like"Who are the patrons?","What is the structure of patronage?", and "How does patronage work in the translation?"Through investigating these issues, the paper concludes that if it had not been for the powerful manipulation by patronage, there could not have been the high-quality translation of such voluminous works. The power of patronage made undeniable contribution to the translation of Selected Works of Deng Xiaoping. 展开更多
关键词 英语学习 学习方法 英语翻译 语言学
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Accuracy analysis of the part made by selected laser sintering 被引量:3
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作者 Zitian FAN Naiyu HUANG +1 位作者 Yuejia XIAO Ming HAN 《China Foundry》 SCIE CAS 2004年第1期49-52,共4页
The effects of different factors, including the precision of selected laser sintering (SLS) equipment, sintering temperature, sintered thickness of individual layer and laser scanning route, on the SLS part accuracy h... The effects of different factors, including the precision of selected laser sintering (SLS) equipment, sintering temperature, sintered thickness of individual layer and laser scanning route, on the SLS part accuracy have been analyzed and studied. Some measures are suggested in order to improve the part accuracy made by SLS. 展开更多
关键词 rapid PROTOTYPING selected LASER SINTERING LASER SCANNING part accuracy
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Evaluation of age, weaning weight, body condition score, and reproductive tract score in pre-selected beef heifers relative to reproductive potential 被引量:2
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作者 Sarah E.Dickinson Michelle F.Elmore +5 位作者 Lisa Kriese-ANDerson Joshua B.Elmore Bailey N.Walker Paul W.Dyce Soren P.Rodning Fernando H.Biase 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2019年第2期307-313,共7页
Background: Artificial insemination is a preferred breeding method for beef heifers as it advances the genetic background, produces a predictive and profitable calving season, and extends the heifer’s reproductive li... Background: Artificial insemination is a preferred breeding method for beef heifers as it advances the genetic background, produces a predictive and profitable calving season, and extends the heifer’s reproductive life span.As reproductive efficiency in heifers is key for the success of beef cattle production systems, following artificial insemination, heifers are exposed to a bull for the remainder of the breeding season. Altogether, up to 95% of heifers might become pregnant in their first breeding season. Heifers that do not become pregnant at the end of the breeding season represent an irreparable economical loss. Additionally, heifers conceiving late in the breeding season to natural service, although acceptable, poses serious losses to producers. To minimize losses due to reproductive failure, different phenotypic parameters can be assessed and utilized as selection tools. Here, we tested the hypothesis that in a group of pre-selected heifers, records of weaning weight, age at weaning, age at artificial insemination, and age of dam differ among heifers of varied reproductive outcomes during the first breeding season.Results: None of the parameters tested presented predictive ability to discriminate the heifers based on the response variable(‘pregnant to artificial insemination’, ‘pregnant to natural service’, ‘not pregnant’). Heifers categorized with body condition score = 6 and reproductive tract score ≥ 4 had the greatest proportion of pregnancy to artificial insemination(49% and 44%, respectively). Furthermore, it was notable that heifers presenting body condition score = 6 and reproductive tract score = 5 presented the greatest pregnancy rate at end of the breeding season(89%). Heifers younger than 368 d at the start of the breeding season did not become pregnant to artificial insemination. Those young heifers had 12.5% chance to become pregnant in their first breeding season,compared to 87.5% if the heifers were older than 368 days.Conclusion: Our results suggest that beef heifers with body condition score = 6 and reproductive tract score ≥ 4 are more likely to become pregnant to artificial insemination. Careful assessment should be undertaken when developing replacement heifers that will not reach 12 months of age by the beginning of the breeding season. 展开更多
关键词 FERTILITY PHENOTYPIC selection PREGNANCY OUTCOME Replacement HEIFER
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Investigating on casting mold (or core) making with coated sand by the selected laser sintering 被引量:6
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作者 Zitian FAN Naiyu HUANG +1 位作者 Yan LI Zhili LIU 《China Foundry》 SCIE CAS 2004年第2期122-126,共5页
Using a special coated sand as the material of the selected laser sintering (SLS), the authors test and investigate the strength change of the test samples in terms of different sintering parameters (scanning speed, l... Using a special coated sand as the material of the selected laser sintering (SLS), the authors test and investigate the strength change of the test samples in terms of different sintering parameters (scanning speed, laser power, sintering thickness, and so on). The characteristics of coated sand hardening by laser beam are analyzed. The sintered mold (or core) for given casting is poured with molten metal. 展开更多
关键词 rapid prototyping selected laser sintering(SLS) laser scanning casting mold(core) technological parameters
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Pyramiding Breeding by Marker-Assisted Recurrent Selection in Upland Cotton: Selected Effects on Resistance to Helicoverpa armigera 被引量:1
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作者 YICheng-xin GUOWang-zhen ZHUXie-fei MINLiu-fang ZHANGTian-zhen 《Agricultural Sciences in China》 CAS CSCD 2004年第5期330-339,共10页
The coincidence rates were more than 96% among the instar-weighted average of bioassaysin the lab, the percentage of resistance to Km in the field and the percentage of plantscontaining Bt gene. So, the performance of... The coincidence rates were more than 96% among the instar-weighted average of bioassaysin the lab, the percentage of resistance to Km in the field and the percentage of plantscontaining Bt gene. So, the performance of resistance to Km in the field can be used torepresent the transgenic Bt gene for selecting the resistance to bollworm. The instar-weighted averages were 30.585, 24.182, 16.615, 10.601, 10.123, 7.440 and 7.215 for theC0, P1, M1, M2, MP1, P2 and MP2 populations, respectively. The variance analysisindicated that the instar-weighted average in C0 was greatly significantly higher thanthat in all other populations, i.e., the performance of resistance to bollworm in C0 washighly significantly lower than all other populations. And the resistance in P1 wasgreatly lower than that of M1, M2, MP1, P2 and MP2, and M1 greatly lower than that of M2,MP1, P2 and MP2. There were no significant differences among M2, MP1, P2 and MP2. Withinthe populations of the first cycle selection, MP1 and M1 were greatly significantlyhigher than P1, and MP1 significantly higher than M1. The populations of the second cycleselection were significantly higher than their initial population M1, but no significantdifference among them. The boll size, seed index, the percent of the first harvest yield,fiber length, strength and elongation of the resistant plants to bollworm were significantlylower than that of sensitive plants to bollworm. And the yield of seed and lint cottonof the resistant plant to bollworm were lower than that of the sensitive to bollworm, butno significant difference between them. The boll numbers per plant, lint percent andmicronaire of the resistant plants to bollworm were significantly higher than that of thesensitive plant to bollworm. 展开更多
关键词 Upland cotton Molecular marker-assisted selection Recurrent selection Pyramiding breeding Resistance to Helicoverpa armigera
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An Improved DV-Hop Localization Algorithm Based on Selected Anchors 被引量:5
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作者 Jing Wang Anqi Hou +1 位作者 Yuanfei Tu Hong Yu 《Computers, Materials & Continua》 SCIE EI 2020年第10期977-991,共15页
Wireless Sensor Network(WSN)based applications has been extraordinarily helpful in monitoring interested area.Only information of surrounding environment with meaningful geometric information is useful.How to design t... Wireless Sensor Network(WSN)based applications has been extraordinarily helpful in monitoring interested area.Only information of surrounding environment with meaningful geometric information is useful.How to design the localization algorithm that can effectively extract unknown node position has been a challenge in WSN.Among all localization technologies,the Distance Vector-Hop(DV-Hop)algorithm has been most popular because it simply utilizes the hop counts as connectivity measurements.This paper proposes an improved DV-Hop based algorithm,a centroid DV-hop localization with selected anchors and inverse distance weighting schemes(SIC-DV-Hop).We adopt an inverse distance weighting method for average distance amelioration to improve accuracy.Also in this paper,we propose an inclusive checking rule to select proper anchors to avoid the inconsistency existing in centroid localization schemes.Finally,an improved multilateration centroid method is presented for the localization.Simulations are conducted on two different network topologies and experiments results show that compared with existing DV-Hop based algorithms,our algorithm can significantly improve the performance meanwhile cost less network resource. 展开更多
关键词 DV-HOP selective mechanism centroid estimation
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Morphological comparison between a selected fast-growing strain and the common cultured strain of turbot Scophthalmus maximus 被引量:4
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作者 梁兴明 马爱军 +3 位作者 王新安 李娟 黄智慧 商晓梅 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第4期563-568,共6页
To evaluate the effect of genetic improvement of the turbot Scophthalmus maximus, we analyzed morphological differences between a fast-growing strain obtained by family selection and the common cultured strain, by pri... To evaluate the effect of genetic improvement of the turbot Scophthalmus maximus, we analyzed morphological differences between a fast-growing strain obtained by family selection and the common cultured strain, by principal component analysis, stepwise discriminant analysis, and t-tests. Although they clearly differed morphologically, plots of the principal components of the two strains partially overlapped. However, the difference between the strains was supported with very high precision by discriminant analysis. The t-tests revealed that 4 of the 13 morphological traits analyzed were highly significantly different (P<0.01), 4 traits also differed significantly (P<0.05), and the remainder did not differ significantly. The coefficients of difference of the 13 traits were all lower than the threshold value between subspecies (1.28). Together, the results indicate that a trend for segregation of characters from the common cultured strain have already appeared in the selected fast-growing strain but the degree of segregation have not risen to subspecies level. 展开更多
关键词 Scophthalmus maximus divergence by selection quantitative trait analysis
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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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Positively selected genes of the Chinese tree shrew (Tupaia belangeri chinensis) locomotion system 被引量:2
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作者 Yu FAN Dan-Dan YU Yong-Gang YAO 《Zoological Research》 CAS CSCD 北大核心 2014年第3期240-248,共9页
While the recent release of the Chinese tree shrew (Tupaia belangeri chinensis) genome has made the tree shrew an increasingly viable experimental animal model for biomedical research, further study of the genome ma... While the recent release of the Chinese tree shrew (Tupaia belangeri chinensis) genome has made the tree shrew an increasingly viable experimental animal model for biomedical research, further study of the genome may facilitate new insights into the applicability of this model. For example, though the tree shrew has a rapid rate of speed and strong jumping ability, there are limited studies on its locomotion ability. In this study we used the available Chinese tree shrew genome information and compared the evolutionary pattern of 407 locomotion system related orthologs among five mammals (human, rhesus monkey, mouse, rat and dog) and the Chinese tree shrew. Our analyses identified 29 genes with significantly high co (Ka/Ks ratio) values and 48 amino acid sites in 14 genes showed significant evidence of positive selection in the Chinese tree shrew. Some of these positively selected genes, e.g. HOXA6 (homeobox A6) and AVP (arginine vasopressin), play important roles in muscle contraction or skeletal morphogenesis. These results provide important clues in understanding the genetic bases of locomotor adaptation in the Chinese tree shrew. 展开更多
关键词 Chinese tree shrew Locomotion system Positively selected genes
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Evaluation of fatty acid metabolism and innate immunity interactions between commercial broiler, F1 layer × broiler cross and commercial layer strains selected for different growth potentials 被引量:1
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作者 Nicky-Lee Willson Rebecca E.A.Forder +3 位作者 Rick G.Tearle Greg S.Nattrass Robert J.Hughes Philip I.Hynd 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2018年第1期156-166,共11页
Background: The broiler industry has undergone intense genetic selection over the past 50 yr. resulting in improvements for growth and feed efficiency, however, significant variation remains for performance and growt... Background: The broiler industry has undergone intense genetic selection over the past 50 yr. resulting in improvements for growth and feed efficiency, however, significant variation remains for performance and growth traits. Production improvements have been coupled with unfavourable metabolic consequences, including immunological trade-offs for growth, and excess fat deposition. To determine whether interactions between fatty acid(FA) metabolism and innate immunity may be associated with performance variations commonly seen within commercial broiler flocks, total carcass lipid %, carcass and blood FA composition, as wel as genes involved with FA metabolism, immunity and cel ular stress were investigated in male birds of a broiler strain, layer strain and F1 layer × broiler cross at d 14 post hatch. Heterophil:lymphocyte ratios, relative organ weights and bodyweight data were also compared.Results: Broiler bodyweight(n = 12) was four times that of layers(n = 12) by d 14 and had significantly higher carcass fat percentage compared to the cross(n = 6; P = 0.002) and layers(P = 0.017) which were not significantly different from each other(P = 0.523). The carcass and whole blood FA analysis revealed differences in the FA composition between the three groups indicating altered FA metabolism, despite al being raised on the same diet. Genes associated with FA synthesis andβ-oxidation were upregulated in the broilers compared to the layers indicating a net overal increase in FA metabolism,which may be driven by the larger relative liver size as a percentage of bodyweight in the broilers. Genes involved in innate immunity such as TLR2 and TLR4, as wel as organel e stress indicators ERN1 and XBP1 were found to be nonsignificant, with the exception of high expression levels of XBP1 in layers compared to the cross and broilers. Additional y there was no difference in heterophil: lymphocytes between any of the birds.Conclusions: The results provide evidence that genetic selection may be associated with altered metabolic processes between broilers, layers and their F1 cross. Whilst there is no evidence of interactions between FA metabolism, innate immunity or cel ular stress, further investigations at later time points as growth and fat deposition increase would provide useful information as to the effects of divergent selection on key metabolic and immunological processes. 展开更多
关键词 Broiler Cel ular stress Fatty acid metabolism Innate immunity Layer selection
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Bull spermatozoa selected by thermotaxis exhibit high DNA integrity,specific head morphometry,and improve ICSI outcome 被引量:1
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作者 Sara Ruiz-Diaz Rosane Mazzarella +8 位作者 Paula Navarrete-Lopez Raul Fernandez-Gonzalez Celia de Frutos Maria Maroto Claudia Cucala Paula Beltran-Brena Marta Lombo Dimitrios Rizos Alfonso Gutierrez-Adan 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第3期1001-1011,共11页
Background Sperm migration by thermotaxis is a guidance mechanism that operates along the oviduct and it has proved to be a valid method for selecting spermatozoa with low DNA fragmentation(SDF)in mice,humans,and stal... Background Sperm migration by thermotaxis is a guidance mechanism that operates along the oviduct and it has proved to be a valid method for selecting spermatozoa with low DNA fragmentation(SDF)in mice,humans,and stallions.This study aimed to analyse if bull spermatozoa could be selected by thermotaxis and to assess their quality in terms of SDF as well as determine the presence of a specific sperm subpopulation based on sperm morphometry and assess their fertilizing capacity by ICSI.Methods We used frozen-thawed sperm from 6 bulls and sperm selection by thermotaxis was performed with TALP medium supplemented with 25 mmol/L of HEPES and 5 mmol/L of caffeine.In these conditions,sperm selection was achieved,obtaining a net thermotaxis of 3.6%.Subsequently,we analysed the SDF of the migrated and not-migrated spermatozoa using the neutral COMET assay,and we evaluated the size of the sperm head using Hemacolor■ staining with Motic Images Plus 3 software.Additionally,migrated and not-migrated spermatozoa by thermotaxis were used to fertilize bovine in vitro matured(IVM)oocytes by ICSI,a very inefficient procedure in cattle that is only successful when the oocyte is artificially activated.Results The results showed lower SDF(χ^(2),P<0.001,13.3%reduction,n=8)and lower head size parameters(length and width,P<0.01;and perimeter and area,P<0.001;n=4)in those spermatozoa migrated in comparison to those not-migrated.The distribution of sperm subpopulations structure varied between groups,highlighting cluster 2,characterized by spermatozoa with small head size,and high ellipticity and elongated heads,as the most abundant in the thermotaxis migrated group.When performed ICSI(without oocyte artificial activation)with the thermotactic sperm,the blastocyst rate was 32.2%±9.3%in the group microinjected with the thermotactic spermatozoa vs.8.3%±7.8%in the group of not-migrated sperm(χ^(2),P<0.05).Conclusion Our results showed that bull sperm selection by thermotaxis has a much higher DNA integrity,small and elongated head size parameters,and different sperm subpopulation structure than the not-selected spermatozoa.Additionally,we evidenced that thermotactic spermatozoa improve ICSI success rates. 展开更多
关键词 ART BOVINE Sperm morphometry Sperm selection THERMOTAXIS
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Pregnancy is not a risk factor for gallstone disease: Results of a randomly selected population sample 被引量:1
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作者 Thomas Walcher Mark Martin Haenle +8 位作者 Martina Kron Birgit Hay Richard Andrew Mason Alexa Friederike Alice von Schmiesing Armin Imhof Wolfgang Koenig Peter Kern Bernhard Otto Boehm Wolfgang Kratzer 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第43期6800-6806,共7页
AIM: To investigate the prevalence, risk factors, and selection of the study population for cholecystolithiasis in an urban population in Germany, in relation to our own findings and to the results in the internation... AIM: To investigate the prevalence, risk factors, and selection of the study population for cholecystolithiasis in an urban population in Germany, in relation to our own findings and to the results in the international literature. METHODS: A total of 2 147 persons (1 111 females, age 42.8 + 12.7 years; 1 036 males, age 42.3 + 13.1 years) participating in an investigation on the prevalence of Echinococcus rnultilocularis were studied for risk factors and prevalence of gallbladder stone disease. Risk factors were assessed by means of a standardized interview and calculation of body mass index (BMI). A diagnostic ultrasound examination of the gallbladder was performed. Data were analyzed by multiple logistic regression, using the SAS statistical software package. RESULTS: Gallbladder stones were detected in 171 study participants (8.0%, n = 2 147). Risk factors for the development of gallbladder stone disease included age, sex, BMI, and positive family history. In a separate analysis of female study participants, pregnancy (yes/no) and number of pregnancies did not exert any influence. CONCLUSION: Findings of the present study confirm that age, female sex, BMI, and positive family history are risk factors for the development of gallbladder stone disease. Pregnancy and the number of pregnancies, however, could not be shown to be risk factors. There seem to be no differences in the respective prevalence for gallbladder stone disease in urban and rural populations. 展开更多
关键词 CHOLECYSTOLITHIASIS PREGNANCY Risk factors selection bias ULTRASONOGRAPHY
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S. E. M. analysis of quartz sand grains from selected Hong Kong and Chinese littoral environments 被引量:2
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作者 A.T.Williams M.C.Thomas 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1989年第3期409-422,共14页
This pilot study attempts to demonstrate some underlying scanning electron microscopy themes of quartz grain surface textures. A variety of textural patterns and individual features are described for grains selected f... This pilot study attempts to demonstrate some underlying scanning electron microscopy themes of quartz grain surface textures. A variety of textural patterns and individual features are described for grains selected from various littoral environments. An attempt was made to differentiate samples on surface textures alone, but limitations of using this technique in sedimentological isolation were apparent. Statistical analysis of checklist data and photographic evidence revealed some of the more important feature combinations used in environmental diagnosis. The use of discriminant analysis provided quantitative sample separation. 展开更多
关键词 In analysis of quartz sand grains from selected Hong Kong and Chinese littoral environments
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Genome-Wide Scan for Positively Selected Genes in Sessile Molluscs Highlights the Genetic Basis for Their Adaptation to Attached Lifestyle
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作者 YU Hong LI Qi 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第4期920-924,共5页
Molluscs are one of the most diverse groups of animals and exhibit a rich and diverse variety of form and lifestyle. Most molluscs live with a free-moving lifestyle, while some molluscs are sessile. The adaptation to ... Molluscs are one of the most diverse groups of animals and exhibit a rich and diverse variety of form and lifestyle. Most molluscs live with a free-moving lifestyle, while some molluscs are sessile. The adaptation to the two distinct lifestyles required complex changes, from molecules to organs, and physiology to morphology. In this study, we conducted a genome-wide scan for positive selection by comparing the available genomes of two sessile molluscs with four free-moving molluscs. A total of 40 genes were identified undergoing positive selection in the sessile molluscs by the branch-site model. Functional characterization showed that they were mainly enriched in two pathways, Oxidative phosphorylation(OXPHOS) and TGF-beta signaling pathway. The unexpected positive selection on OXPHOS genes in sessile molluscs suggests that the adaptation of OXPHOS involves many factors beyond enhancing ATP production. A modified OXPHOS regulatory system may allow sessile molluscs to better cope with biotic and abiotic stresses. Moreover, positively selected genes in TGF-beta signaling pathway probably have played a key role in the patterning of body plans and growth in metazoans. We speculate that these genes are associated with the body structure and organic adaptation to a sedentary lifestyle in sessile bivalve molluscs. 展开更多
关键词 molluscs ADAPTATION evolution positive selection sessile LIFESTYLE
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Deep Learning for Wind Speed Forecasting Using Bi-LSTM with Selected Features 被引量:1
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作者 Siva Sankari Subbiah Senthil Kumar Paramasivan +2 位作者 Karmel Arockiasamy Saminathan Senthivel Muthamilselvan Thangavel 《Intelligent Automation & Soft Computing》 SCIE 2023年第3期3829-3844,共16页
Wind speed forecasting is important for wind energy forecasting.In the modern era,the increase in energy demand can be managed effectively by fore-casting the wind speed accurately.The main objective of this research ... Wind speed forecasting is important for wind energy forecasting.In the modern era,the increase in energy demand can be managed effectively by fore-casting the wind speed accurately.The main objective of this research is to improve the performance of wind speed forecasting by handling uncertainty,the curse of dimensionality,overfitting and non-linearity issues.The curse of dimensionality and overfitting issues are handled by using Boruta feature selec-tion.The uncertainty and the non-linearity issues are addressed by using the deep learning based Bi-directional Long Short Term Memory(Bi-LSTM).In this paper,Bi-LSTM with Boruta feature selection named BFS-Bi-LSTM is proposed to improve the performance of wind speed forecasting.The model identifies relevant features for wind speed forecasting from the meteorological features using Boruta wrapper feature selection(BFS).Followed by Bi-LSTM predicts the wind speed by considering the wind speed from the past and future time steps.The proposed BFS-Bi-LSTM model is compared against Multilayer perceptron(MLP),MLP with Boruta(BFS-MLP),Long Short Term Memory(LSTM),LSTM with Boruta(BFS-LSTM)and Bi-LSTM in terms of Root Mean Square Error(RMSE),Mean Absolute Error(MAE),Mean Square Error(MSE)and R2.The BFS-Bi-LSTM surpassed other models by producing RMSE of 0.784,MAE of 0.530,MSE of 0.615 and R2 of 0.8766.The experimental result shows that the BFS-Bi-LSTM produced better forecasting results compared to others. 展开更多
关键词 Bi-directional long short term memory boruta feature selection deep learning machine learning wind speed forecasting
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Imaging alignment of rotational state-selected CH_3I molecule
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作者 Le-Le Song Yan-Hui Wang +9 位作者 Xiao-Chun Wang Hong-Tao Sun Lan-Hai He Si-Zuo Luo Wen-Hui Hu Dong-Xu Li Wen-Hui Zhu Ya-Nan Sun Da-Jun Ding Fu-Chun Liu 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第2期167-172,共6页
We experimentally and numerically investigate CH_3I molecular alignment by using a femtosecond laser and a hexapole. The hexapole provides the single |111〉rotational state condition at 4.5-kV hexapole rod voltage. Ba... We experimentally and numerically investigate CH_3I molecular alignment by using a femtosecond laser and a hexapole. The hexapole provides the single |111〉rotational state condition at 4.5-kV hexapole rod voltage. Based on this single rotational state, an enhanced alignment degree of 0.73 is achieved. Our experimental results are in agreement with the simulation results. We experimentally obtain the ion velocity map images and show the influence of the initial rotational-state population. With the I+ion images and angular distributions at different pump-probe delay time, the alignment and anti-alignment phenomena are further demonstrated. The molecules will be under field-free conditions when the laser effect disappears completely at the full revival time. Our work shows that the quantum control and spatial control on CH_3I molecules can be realized and molecular coordinate frame can be obtained for further molecular experiment. 展开更多
关键词 hexapole state selection VELOCITY MAP IMAGING ALIGNMENT
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Novel Face Recognition Method by Combining Spatial Domain and Selected Complex Wavelet Features 被引量:1
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作者 张强 蔡云泽 许晓鸣 《Journal of Donghua University(English Edition)》 EI CAS 2011年第3期285-290,共6页
A novel face recognition method based on fusion of spatial and frequency features was presented to improve recognition accuracy. Dual-Tree Complex Wavelet Transform derives desirable facial features to cope with the v... A novel face recognition method based on fusion of spatial and frequency features was presented to improve recognition accuracy. Dual-Tree Complex Wavelet Transform derives desirable facial features to cope with the variation due to the illumination and facial expression changes. By adopting spectral regression and complex fusion technologies respectively, two improved neighborhood preserving discriminant analysis feature extraction methods were proposed to capture the face manifold structures and locality discriminatory information. Extensive experiments have been made to compare the recognition performance of the proposed method with some popular dimensionality reduction methods on ORL and Yale face databases. The results verify the effectiveness of the proposed method. 展开更多
关键词 face recognition neighborhood preserving discriminant analysis spectral regression complex fusion Dual-Tree Complex Wavelet Transform feature selection
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