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Growth Performance of Different Cross Combinations of Quality Lean Type Pig
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作者 SHEN Xue-lin DUAN Yong-bang 《Animal Husbandry and Feed Science》 CAS 2013年第5期224-226,共3页
Ten healthy weaning piglets of Landrace x Yorkshire (LY) in good body condition with body weight of (24 ± 1.27) kg were selected, and ten weaning piglets of Berkshire × LY (BLY) and Duroc × LY (... Ten healthy weaning piglets of Landrace x Yorkshire (LY) in good body condition with body weight of (24 ± 1.27) kg were selected, and ten weaning piglets of Berkshire × LY (BLY) and Duroc × LY (DLY) with similar situation were also selected respectively to study the growth performance of different cross combinations. Three groups of experimental pigs were bred with conventional diet. The results showed that the average dry matter intakes of combinations of BLY and DLY were slightly decreased by 4.97% and 5.47% compared with the combination of LY, while average daily gain was significantly increased by 3.13% and 1.14%, and feed-weight ratio was decreased by 7.94% and 6.35%, respectively; economic benefit per pig was increased by 0.61 and 0.41 yuan, respectively. The combinations of BLY and DLY have better growth performance, which can be promoted in the production. 展开更多
关键词 Lean type pig cross combinations Growth performance
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Combining ability and heterosis analysis over two environments in a diallel cross of three families of the clam Meretrix meretrix 被引量:3
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作者 DAI Ping WANG Hongxia +1 位作者 XIAO Guoqiang LIU Baozhong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第10期37-42,共6页
A 3×3 complete diallel cross comprising three families of the clam Meretrix meretrix(P1, P2 and P3) was used to determine the combining ability of parental families and heterosis of F1 under indoor and openair ... A 3×3 complete diallel cross comprising three families of the clam Meretrix meretrix(P1, P2 and P3) was used to determine the combining ability of parental families and heterosis of F1 under indoor and openair environments for growth traits. Analysis of variance for shell length and whole body weight indicated highly significant cross effects, environment effects and the interaction of cross by environment. General combining ability(GCA) and specific combing ability exhibited great variation among crosses and between two environments. Pooled over environments, P2 was the top combiner among the three parental families for both traits studied. The cross of P1 and P3 had the highest SCA. Additionally, significant reciprocal effects were observed. For individual environment, about half of the crossbred combinations showed favorable Mid-parent heterosis(MPH)(〉1%) for the shell length and whole body weight. Our data has shown that non-additive genetic and reciprocal effects constituted the major sources of genetic variation for both shell length and whole body weight, which indicates that crossbreeding among selective families could further explore the heterotic effects. 展开更多
关键词 Meretrix meretrix general and specific combining ability reciprocal effects HETEROSIS diallel cross
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Variation Analysis of Seed and Seedling Traits of Cross Combination Progenies in Populus 被引量:3
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作者 Li Shan-wen Zhang Zhiyi +3 位作者 He Cheng-zhong An Xin-min Yu Zhi-shui Li Bai-lian 《Forestry Studies in China》 CAS 2005年第3期61-69,共9页
Twenty-five species and hybrids in Populus were used as parents, and 26 cross combinations, including more than 5000 seedlings, were obtained by artificial cross breeding. The length of infructescence, number of seeds... Twenty-five species and hybrids in Populus were used as parents, and 26 cross combinations, including more than 5000 seedlings, were obtained by artificial cross breeding. The length of infructescence, number of seeds per infructescence, thousand-seed weight, germination rate of seeds among these cross combinations were tested. The results indicated that the cross combinational effects were significant for these traits, and demonstrated that the length of infructescence, thousand-seed weight were positively affected by female parent. In addition, seedling height, diameter above ground, diameter at breast height (DBH) of 17 cross combination progenies were investigated. The analysis of mean and standard deviation of these three traits showed that seedling height, diameter above ground, DBH had extensive variation among combinations and individuals within combination. Variance analysis and estimate of heritability indicated that the three traits had wide variation and were controlled by heredity. It was feasible to select superior cross combinations and seedlings. Further more, the result of multiple comparison showed that P.deltoides ‘Lux'× P.deltoides ‘D324', P.ussuriensis cl. ‘U4'× P deltoides ‘T66', P.ussuriensis cl. ‘U4'× P. deltoides ‘T26', P.deltoides ‘Lux'× P.ussuriensis cl. ‘U3', (P.tomentosa×P.bolleana)×(P.alba×P.glandulosa), (P.alba×P.tomentosa)×(P.alba×P.glandulosa), and (P.alba×P.glandulosa‘No.2')× P. tomentosa ‘Lumao 50' were superior cross combinations with higher growth rate. Finally, 123 elite seedlings were selected for further test. 展开更多
关键词 POPLAR cross combination HYBRID variation analysis
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Determination of Polynomial Degree in the Regression of Drug Combinations 被引量:1
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作者 Boqian Wang Xianting Ding Fei-Yue Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2017年第1期41-47,共7页
Studies on drug combinations are becoming more and more popular in the past few decades, with the development of computer and algorithms. One of the most common methods in optimizing drug combinations is regression of... Studies on drug combinations are becoming more and more popular in the past few decades, with the development of computer and algorithms. One of the most common methods in optimizing drug combinations is regression of a polynomial model based on certain number of experimental observations. In this paper, we study how to determine the degree of polynomials in different circumstances of drug combination optimization. Using cross-validation, we have found that in most cases, a high degree results in failures of accurate prediction, named overfitting. An anti-noise test has also revealed that polynomial model with high degree tends to be less resistant to random errors in the observations. © 2014 Chinese Association of Automation. 展开更多
关键词 ACOUSTICS Random errors Regression analysis
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Improvement of heat-tolerance by training I. Evaluation of effects of combined of march and cross-country race on heat-tolerance
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作者 邱仞之 朱受成 万为人 《Journal of Medical Colleges of PLA(China)》 CAS 1996年第4期253-257,共5页
in order to improve the acquired level of heat acclimatization (HA) by training, on the basis of singlemode march training (SMT) or single-mode cross-country race training (SCT) , combined training method of march and... in order to improve the acquired level of heat acclimatization (HA) by training, on the basis of singlemode march training (SMT) or single-mode cross-country race training (SCT) , combined training method of march and cross-country race in the heat was adopted in this experiment ,and the effect of the training on heat tolerance was analyzed. Eight young males were asked to perform a simulated SMT and SCT for 90 min on a treadmill in a hot climate chamber (Td 32. 7℃ , WBGT 28. 4℃ ) once daily for 10 to 12 d within two weeks. The results showed that rectal temperature (Tr) was reduced by 0. 61℃ , heart rate (Hr) by 8. 5 b/min,sweat volume (SV)by 0. 220 kg, physiological strain index (PSI)by 0. 620,systolic pressure (SP)and diastolic pressure (DP) had a little change, pulse pressure (PP) and stroke volume (StV) increased , and cardiac output (CO) decreased a little at the middle stage and increased at the late stage due to Hr change. The standardized bicycle ergometer test (SBE test) in the heat (Td 37℃)has proved that these physiological indexes post-training had significant improvements ,as compared with those pre-training, suggesting that the combined training could raise heat-tolerance and was superior to the SMT in improving acquired heat acclimatization in same training duration and times , and to the SCT in regulating body temperature and cardiovascular function and in prolonging heat tolerance duration. 展开更多
关键词 combined TRAINING MARCH cross-COUNTRY RACE HEAT acclimatization HEAT TOLERANCE
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双髋关节MRI预测股骨头坏死塌陷风险
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作者 晋继明 郝阳泉 +4 位作者 赵汝顺 张玉婷 姜永宏 许鹏 鲁超 《中国组织工程研究》 CAS 北大核心 2025年第9期1890-1896,共7页
背景:MRI是诊断股骨头坏死的金标准,以往基于MRI图像预测股骨头坏死塌陷的方法多需要冠状面、矢状面图像联合评估。然而由于股骨头坏死好发于双侧,临床上大多医院检查时多行双侧髋关节MRI扫描,但双髋扫描仅可查看冠状面及横断面图像,难... 背景:MRI是诊断股骨头坏死的金标准,以往基于MRI图像预测股骨头坏死塌陷的方法多需要冠状面、矢状面图像联合评估。然而由于股骨头坏死好发于双侧,临床上大多医院检查时多行双侧髋关节MRI扫描,但双髋扫描仅可查看冠状面及横断面图像,难以获取矢状面图像,从而影响塌陷风险的评估。因此,建立一种应用双髋MRI可获取的图像评估早期股骨头坏死塌陷风险的方法有一定的临床实用价值。目的:建立一种应用双髋关节MRI冠状面与横断面图像评估股骨头坏死塌陷风险的方法。方法:回顾性分析2017年10月至2019年10月在西安交通大学附属红会医院门诊确诊的早期股骨头坏死患者111例(181髋)的病历资料。根据末次随访时股骨头塌陷情况分为2组,其中塌陷组69髋,未塌陷组112髋。在MRI影像系统上测量正中冠状面、横断面或其上下各一个层面图像上的坏死范围角度,以冠状面、横断面上坏死角两角之和作为联合坏死角,并取每髋3种联合坏死角的平均值得到每髋的平均联合坏死角。最后,分析3种联合坏死角及平均联合坏死角与股骨头坏死塌陷的相关性,利用受试者工作特征曲线评价4种联合坏死角预测塌陷的特异性与敏感性。结果与结论:①末次随访69髋(38.1%)发生股骨头塌陷,纳入塌陷组;112髋(61.9%)未发生塌陷进展,纳入非塌陷组;②塌陷组与未塌陷组在ARCO分期方面比较差异有显著性意义(P<0.001);在年龄、体质量指数、随访时间、性别分布、发病侧别、致病因素等方面比较差异均无显著性意义(P>0.05);③独立样本t检验结果提示,4种联合坏死角均与塌陷显著相关(P<0.0001);且ARCOⅠ期、Ⅱ期中塌陷组与未塌陷组患者的联合坏死角相比差异均有显著性意义(P<0.0001);④在受试者工作特征分析中,平均联合坏死角曲线下面积大于正中下一层面、正中层面、正中上一层面上的联合坏死角;⑤平均联合坏死角塌陷预测准确度高于正中下一层面、正中层面、正中上一层面上的联合坏死角;⑥提示平均联合坏死角对股骨头坏死塌陷风险的预测精准度较高,临床实用性较强,可考虑使用该方法对股骨头坏死塌陷风险进行预测。 展开更多
关键词 股骨头坏死 塌陷预测 MRI 冠状面 横断面 联合坏死角
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Heterosis and Combining Ability for Major Yield Traits of a New Wheat Germplasm Shannong 0095 Derived from Thinopyrum intermedium 被引量:8
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作者 BAO Yin-guang WANG Sen +4 位作者 WANG Xiu-qin WANG Yu-hai LI Xing-feng WANG Lin WANG Hong-gang 《Agricultural Sciences in China》 CAS CSCD 2009年第6期753-760,共8页
The wheatgrass, Thinopyrum intermedium (Host) Barkworth & DR Dewey, shows many beneficial characteristics, such as big spikes and high resistance to many diseases. To transfer the beneficial genes of this species, ... The wheatgrass, Thinopyrum intermedium (Host) Barkworth & DR Dewey, shows many beneficial characteristics, such as big spikes and high resistance to many diseases. To transfer the beneficial genes of this species, many wheat- Thinopyrum intermedium alien chromosome lines were developed. Of them, Shannong 0095 (SN0095), a disomic substitution, has long spikes and flag-leaves, and thus may be an important genetic resource for wheat yield improvement. In order to realize its heterosis and combining ability on major yield traits, a 7 ×7 complete diallel design was made according to Griffing's Method-1. The results showed that heterosis for spike length (SPL), flag-leaf area (FLA), number of spikes per plant (NSP), number of spikelets per spike (NSL), kernels per spike (KPS), 1 000-kernel weight (TKW) and grain yield per plant (GYP) existed in all the crosses by SN0095, but heterobeltiosis occurred only for KPS, TKW, and GYP. The relative mid-parent heterosis (RMH) and relative high-parent heterosis (RHH) for GYP, which valued as high as 35.32 and 29.92% respectively, were the highest among all the traits mearsured. Though additive and non-additive gene effects and cytoplasmic effects (or cytoplasmic-nuclear interaction effects) were found in governing all the traits measured above, additive gene action played a predominant role. The results also showed that SN0095 was the best-general combiner for SPL and FLA, and high-general combiner for NSP amongst all the parents. Estimates of specific combining ability (SCA) showed that SN0095 could also make high-SCA combinations for GYP, such as SN0095 × Jimai 19 (JMI9). SN0095 could be a unique and important parent in hybrid wheat breeding programs. 展开更多
关键词 Triticum aestivum Thinopyrum intermedium diallel cross combining ability HETEROSIS
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Combining Ability and Genetic Effects of Germination Traits of Brassica napus L.Under Waterlogging Stress Condition 被引量:5
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作者 CHENG Yong GU Min +3 位作者 CONG Ye ZOU Chong-shun ZHANG Xue-kun WANG Han-zhong 《Agricultural Sciences in China》 CAS CSCD 2010年第7期951-957,共7页
Cross combinations from six rapeseed cultivars and lines were evaluated under waterlogging stress condition in order to understand the genetic mechanism of waterlogging tolerance of Brassica napus L.and provide reason... Cross combinations from six rapeseed cultivars and lines were evaluated under waterlogging stress condition in order to understand the genetic mechanism of waterlogging tolerance of Brassica napus L.and provide reasonable improvement programs.There were six germination traits investigated on combining ability and heritability using complete diallel crossing method designed for 30 combinations from those six cultivars and lines.The traits included relative root length,stem length,fresh weight per plant,survival rate,electrical conductivity,and vigor index.After flooding treatment,the six traits of parents and F1 were analyzed.The general combining ability(GCA) and special combining ability(SCA) of germination traits were analyzed using Griffing I method.Among 30 cross combinations,the GCA was significantly different among six waterlogging resistance traits.The SCA of these traits was significantly different except the SCA of electrical conductivity.As a representative trait of waterlogging tolerance in rapeseed,relative vigor index had the highest narrow heritability and relatively low broad heritability.The cultivars Zhongshuang 9 and P79 had higher tolerance potential to waterlogging stress.It can be concluded that combining ability and genetic effects of relative vigor index during germination stage could be used to identify the waterlogging tolerance of rapeseed in breeding program. 展开更多
关键词 Brassica napus L. relative vigor index waterlogging tolerance germination trait combining ability diallel crossing
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Combining Ability and Parent-Offspring Correlation of Maize(Zea may L.) Grain β-Carotene Content with a Complete Diallel 被引量:1
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作者 LI Run XIAO Lan-hai +7 位作者 WANG Jing LUYan-li RONG Ting-zhao PAN Guang-tang WU Yuan-qi TANG Qilin LAN Hai CAO Mo-ju 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第1期19-26,共8页
Vitamin A deficiency has become a worldwide problem.Biofortified foods can potentially be an inexpensive,locally adaptable,and long-term solution to dietary-nutrient deficiency.In order to improve the β-carotene cont... Vitamin A deficiency has become a worldwide problem.Biofortified foods can potentially be an inexpensive,locally adaptable,and long-term solution to dietary-nutrient deficiency.In order to improve the β-carotene content in maize grain by breeding and minimize vitamin A deficiency,a complete diallel cross was designed with eight inbred lines of maize,and 64 combinations were obtained in this study.The experimental combinations were planted in Yunnan and Sichuan provinces,respectively,with a random complete block design.The β-carotene contents in the grains of the experimental materials were analyzed by high-performance liquid chromatography.Among the tested materials,the effect difference of general combining ability of the β-carotene content was significant;however,the effect difference of the special combining ability and the reciprocal effect were not significant.The β-carotene content of maize grain was not influenced significantly by the cross and the reciprocal cross.There was a significant correlation about the β-carotene content in the maize grains between the F 1 and their parents.The combinations with high β-carotene content were obviously influenced by the environment,and the mean value of β-carotene content for the experimental materials planted in Ya'an of Sichuan was higher than that planted in Yuanjiang of Yunnan,with the results being significant at the 0.01 level. 展开更多
关键词 MAIZE β-carotene content complete diallel cross combining ability
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Simple, Rapid and Sensitive Detection of Pseudomonas aeruginesa by Colorimetric Multiple Cross Displacement Amplification
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作者 Dong-xun LI Gao-lin SHU +2 位作者 Wei-jun WANG Yang WU Huan-cai NIU 《Current Medical Science》 SCIE CAS 2020年第2期372-379,共8页
Pseudomonas aeruginosa(P:aeruginosa)is a major opportunistic pathogen in hospital-acquired infections.Thus,carly diagnosis is the best strategy for fighting against these infections.In this report,we incorporated mult... Pseudomonas aeruginosa(P:aeruginosa)is a major opportunistic pathogen in hospital-acquired infections.Thus,carly diagnosis is the best strategy for fighting against these infections.In this report,we incorporated multiple crOsS displacement amplification(MCDA)combined with the malachite green(MG)for rapid,sensitive,specific and visual detection of P.aeruginosa by targeting the oprl gene.The MCDA-MG assay was conducted at 67°C for only 40 min during the amplification stage,and then products were directly detected by using colorimetric indicators(MG),eliminating the use of an electrophoresis instrument or amplicon analysis equipment.The entire process,including specimen processing(35 min),amplification(40 min)and detection(5 min),can be finished within 80 min.All 30 non-P.aeruginosa strains tested negative,indicating the high specificity of the MCDA primers.The analytical sensitivity of the MCDA-MG assay was 100 fg of genomic templates per reaction in pure culture,which was in complete accordance with MCDA by gel clectrophoresis and real-time turbidity.The assay was also successfully applied to detecting P.aeruginosa in stool samples.Therefore,the rapidity,simplicity,and nearly equipment free platform of the MCDA-MG technique make it possible for clinical diagnosis,and more. 展开更多
关键词 Pseudomonas aeruginosa multiple cross displacement amplification malachite green multiple cross displacement amplification combined with the malachite green
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大豆杂交育种组合规模与品种选育概率及亲本选用研究 被引量:1
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作者 郭泰 郭美玲 +5 位作者 李灿东 王志新 郑伟 徐杰飞 赵星棋 王象然 《黑龙江农业科学》 2024年第4期1-10,共10页
为指导当前与今后的大豆杂交育种工作,以黑龙江省农业科学院佳木斯分院1952-2013年间杂交育种选用的有效亲本和配制的杂交组合及选育的新品种为研究对象,对116个有效亲本和5610个杂交组合及110个品种进行深入系统地研究与分析。结果表明... 为指导当前与今后的大豆杂交育种工作,以黑龙江省农业科学院佳木斯分院1952-2013年间杂交育种选用的有效亲本和配制的杂交组合及选育的新品种为研究对象,对116个有效亲本和5610个杂交组合及110个品种进行深入系统地研究与分析。结果表明,杂交组合配制规模以每年150~200个为宜,选育品种概率为1.96%;亲本选择要依据育种理论、育种目标和遗传背景;亲本选用原则要坚持高起点、要考虑亲本血缘关系与遗传基础、亲本配合力(一般配合力和特殊配合力)及目标性状遗传特点;亲本使用要确定核心亲本(骨干亲本)与改良亲本,要采用梯级杂交、连续改造或回交转育、定向改良或一母多父,集中围攻或采用多亲本杂交聚合育种。 展开更多
关键词 大豆杂交育种 组合规模 品种选育概率 亲本选用
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地震-波浪联合作用下考虑冲刷效应的跨海斜拉桥振动台试验研究
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作者 李忠献 郑庆涛 +1 位作者 苏俊省 赵博 《土木工程学报》 EI CSCD 北大核心 2024年第10期71-81,共11页
针对跨海桥梁服役期内可能遭受地震、波浪以及冲刷效应影响的问题,开展地震与波浪联合作用下考虑冲刷效应的跨海斜拉桥振动台试验,研究地震与波浪联合作用下冲刷效应对斜拉桥动力特性及关键截面动力响应(加速度、位移和应变)的影响规律... 针对跨海桥梁服役期内可能遭受地震、波浪以及冲刷效应影响的问题,开展地震与波浪联合作用下考虑冲刷效应的跨海斜拉桥振动台试验,研究地震与波浪联合作用下冲刷效应对斜拉桥动力特性及关键截面动力响应(加速度、位移和应变)的影响规律。研究表明:随着冲刷深度的增加,斜拉桥自振频率逐渐降低;冲刷深度的增加,降低了桥塔桩基础侧向约束,引起地震与波浪联合作用下桩顶动力响应明显增大,且增幅比其他位置更为显著;边墩墩顶加速度和相对位移均大于辅助墩墩顶,桥墩抗震设计时,应采用不同配筋率和不同的截面尺寸对边墩和辅助墩开展差异化设计;考虑冲刷效应明显增大了地震与波浪联合作用下塔底、边墩和辅助墩墩底等关键截面的应变,相较于无冲刷工况,大冲刷工况下塔底、边墩及辅助墩墩底应变分别增加39%、36%和42%,抗震设计时应高度重视。 展开更多
关键词 跨海斜拉桥 振动台试验 地震-波浪联合作用 冲刷效应 动力响应
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不同杂交组合鸡蛋品质的比较分析 被引量:2
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作者 蒋一秀 邹明阳 +6 位作者 薛倩 周成浩 张会永 殷建玫 夏树立 李国辉 韩威 《中国家禽》 北大核心 2024年第2期113-118,共6页
试验旨在研究以芦花鸡H系作为亲本的杂交组合蛋品质的差异,为地方鸡种的利用与开发提供理论依据。试验选择萧山鸡(X)、狼山鸡(L)、隐形白羽肉鸡(Y)、来航鸡(H),分别与芦花鸡H系(B)进行正反杂交(F1代),共7个试验组和2个对照组(B、L),每... 试验旨在研究以芦花鸡H系作为亲本的杂交组合蛋品质的差异,为地方鸡种的利用与开发提供理论依据。试验选择萧山鸡(X)、狼山鸡(L)、隐形白羽肉鸡(Y)、来航鸡(H),分别与芦花鸡H系(B)进行正反杂交(F1代),共7个试验组和2个对照组(B、L),每组15个重复。每个组合分别留取同期8 d的受精蛋F2代,孵化后在同一饲养条件和营养水平下饲养至43周龄,每个试验组分别收取30个鸡蛋测定蛋品质。结果显示:各试验组蛋重与对照组B差异不显著(P>0.05);试验组XB蛋黄重极显著高于对照组L(P<0.01);试验组BL、LB蛋黄比率与对照组B、L无显著差异(P>0.05);各试验组及对照组蛋白高度差异不显著(P>0.05);试验组BX、BL、XB、YB蛋壳强度极显著高于对照组L(P<0.01),与对照组B差异不显著(P>0.05);试验组BX、BL、BH、XB、YB蛋壳厚度均极显著高于对照组B和L(P<0.01);蛋黄色泽与蛋重、蛋黄重、蛋黄比率极显著相关(P<0.01),与蛋壳强度显著相关(P<0.05);主成分分析选取5个主成分,特征根累计贡献率为82.852 0%,包含所有杂交组合蛋品质的基本信息。由此可见,芦花鸡H系在与其他地方品种或引进品种杂交时,可较好地保持地方品种蛋品质特性,在选育过程中是优良的亲本素材。 展开更多
关键词 芦花鸡H系 杂交组合 蛋品质 相关性分析 主成分分析
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风-浪联合作用下斜拉-悬索协作体系桥车-桥耦合振动仿真研究
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作者 祝兵 员帅伟 +1 位作者 王浩宇 殷瑞涛 《桥梁建设》 EI CSCD 北大核心 2024年第6期23-31,共9页
为保证海洋环境下斜拉-悬索协作体系桥列车运行的安全性和舒适度,对该类桥梁进行风-浪联合作用下的车-桥耦合振动仿真研究。以某公铁两用斜拉-悬索协作体系桥为背景,采用ANSYS软件建立桥梁有限元模型,采用多体系统动力学软件SIMPACK建... 为保证海洋环境下斜拉-悬索协作体系桥列车运行的安全性和舒适度,对该类桥梁进行风-浪联合作用下的车-桥耦合振动仿真研究。以某公铁两用斜拉-悬索协作体系桥为背景,采用ANSYS软件建立桥梁有限元模型,采用多体系统动力学软件SIMPACK建立列车动力学模型,利用重叠网格技术,模拟车-桥耦合系统在不同风速和车速下的气动荷载,采用FLOW-3D软件计算桥梁下部复合基础的规则波浪荷载,建立风-浪联合作用下的车-桥耦合振动模型,分析波高、风速和车速对车-桥耦合系统动力响应的影响规律。结果表明:在风-浪-车-桥耦合系统中,列车各动力学指标均随波高增大而增大,桥梁跨中横向位移随波高增大而显著增大,而跨中竖向位移几乎不受影响;列车各动力学指标均随风速提高而显著增大,桥梁跨中竖向位移随风速提高而减小;列车各动力学指标均随车速增大而增大,桥梁跨中横向位移和横向加速度不随车速改变而显著变化,桥梁竖向位移和竖向加速度随车速提高而显著增大。 展开更多
关键词 斜拉-悬索协作体系桥 公路铁路两用桥 跨海桥梁 风-浪联合作用 车-桥耦合振动 重叠网格技术 气动荷载 有限元法
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跨文化视角下的儿童感觉统合障碍治疗:中医与心理疗法的结合
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作者 冯璐 马宁 +1 位作者 董鹤婷 王钰水 《实用中医内科杂志》 2024年第7期96-99,共4页
随着具有感觉统合障碍儿童数量的增加,社会越来越关注感觉统合障碍的问题。研究表明,感觉统合障碍儿童是可以通过及时的、科学的干预治疗得到良好恢复的。因此为研究跨文化视角下的儿童感觉统合障碍治疗,深入探讨了中医与心理疗法相结... 随着具有感觉统合障碍儿童数量的增加,社会越来越关注感觉统合障碍的问题。研究表明,感觉统合障碍儿童是可以通过及时的、科学的干预治疗得到良好恢复的。因此为研究跨文化视角下的儿童感觉统合障碍治疗,深入探讨了中医与心理疗法相结合的创新治疗模式。首先,根据东西方文化差异探讨跨文化认知背景下儿童感觉统合障碍的差异;其次,从理论及应用等方面阐述中医诊疗和心理疗法诊疗的各自作用,从综合诊断和综合干预的角度阐述中医与心理疗法结合的可行性;最后,从跨学科合作、个性化治疗、社区化服务角度出发,展望中医与心理疗法结合的未来发展趋势。文章围绕中医与心理疗法的结合进行综述,为进一步研究开发提供参考。 展开更多
关键词 跨文化视角 儿童感觉统合障碍 中医 心理疗法 中医与心理疗法结合
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基于虾夷扇贝自交家系的双列杂交配合力分析
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作者 赵亮 高杉 +1 位作者 蒋经伟 周遵春 《水产科学》 CAS CSCD 北大核心 2024年第4期541-549,共9页
为评估“先纯后杂”种质改良技术在虾夷扇贝中的应用效果,利用3个自交F_(1)家系(21#、12#、16#)的子代,采用3×3完全双列杂交构建包含亲本正反交的9种组合,统计幼虫期和成体期的成活率性状并开展配合力分析。试验结果显示:自幼虫期... 为评估“先纯后杂”种质改良技术在虾夷扇贝中的应用效果,利用3个自交F_(1)家系(21#、12#、16#)的子代,采用3×3完全双列杂交构建包含亲本正反交的9种组合,统计幼虫期和成体期的成活率性状并开展配合力分析。试验结果显示:自幼虫期3日龄起,各阶段存活率均有显著差异(P<0.05);3组亲本的一般配合力的大小和方向均不相同,在27、140、200、440日龄一般配合力差异显著(P<0.05),尤其在140日龄差异极显著(P<0.01),效应值为-6.88~8.25;在幼虫期,不同交配组合中62.96%的特殊配合力与其反交组合是相反的方向,16#×12#展现出较高的特殊配合力,最高值达18.33;在成体期特殊配合力的大小和方向也不同,从幼虫到成体的转换期(27~140日龄)多数组合出现了效应值下降趋势。21#×12#、16#×12#组合在存活率上的杂种优势展现了合理运用“先纯后杂”的育种策略的有效性;同时21#×21#、12#×12#、16#×16#组合在存活率上的优势显示了虾夷扇贝具有较强的遗传负荷清除效率。试验结果可为虾夷扇贝遗传改良提供基础数据。 展开更多
关键词 虾夷扇贝 双列杂交 一般配合力 特殊配合力 自交
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跨医学体系下医疗知识图谱的构建与药物预测研究——以动脉粥样硬化为例 被引量:1
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作者 张君冬 杨松桦 +3 位作者 严颖 李娜 刘江峰 黄奇 《情报理论与实践》 CSSCI 北大核心 2024年第2期178-188,共11页
[目的/意义]探讨跨医学体系下的医疗知识图谱构建框架,促进医疗健康数据的有机融合和深层次互通。[方法/过程]以5个国内公开的大型医学数据库为数据来源,通过知识重组、实体对齐、关系融合构建医疗知识图谱,在此基础上,以动脉粥样硬化... [目的/意义]探讨跨医学体系下的医疗知识图谱构建框架,促进医疗健康数据的有机融合和深层次互通。[方法/过程]以5个国内公开的大型医学数据库为数据来源,通过知识重组、实体对齐、关系融合构建医疗知识图谱,在此基础上,以动脉粥样硬化这一疾病为例,进行药物预测实证研究。[结果/结论]最终形成包含153849个实体、6569280个三元、73种语义关系的医疗知识图谱,为改善因医学体系差异性而导致的中西医“松散”联系现状做出了积极探索,提升了现有医疗知识图谱的知识服务范围,同时也为解析药物预测结果带来了新的研究思路。 展开更多
关键词 跨医学体系 医疗知识图谱 术语关联 链路预测 药物预测 中西医结合
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圆截面组合桩加固滑坡的作用机理与合理嵌固深度物理模型试验研究
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作者 宋成彬 李长冬 +3 位作者 王贵华 姚文敏 贺鑫 方堃 《安全与环境工程》 CAS CSCD 北大核心 2024年第1期135-149,共15页
目前在滑坡治理中,大截面人工挖孔桩因存在施工安全隐患大和效率低下等问题已在部分行业领域被限制使用,开展可机械化施工的圆截面组合桩研究已成为新的趋势,但当前对圆截面组合桩变形受力机理与合理嵌固深度的研究尚不够深入。基于自... 目前在滑坡治理中,大截面人工挖孔桩因存在施工安全隐患大和效率低下等问题已在部分行业领域被限制使用,开展可机械化施工的圆截面组合桩研究已成为新的趋势,但当前对圆截面组合桩变形受力机理与合理嵌固深度的研究尚不够深入。基于自主研发的圆截面组合桩加固滑坡物理模型试验系统,开展了不同工况下圆截面组合桩加固滑坡的物理模型试验,分析了滑体的变形演化过程,研究了圆截面组合桩加固下滑体与抗滑桩的变形受力特征,并对比分析了不同嵌固深度和桩顶连系梁对圆截面组合桩变形特征的影响,揭示了圆截面组合桩加固滑坡的作用机理。结果表明:①滑体的变形演化过程可分为压密、匀速变形、加速变形和变形破坏4个阶段;②前后桩均存在反弯点,反弯点会随着试验进程向桩顶移动,且后桩的反弯点更接近于滑动面;③当一排桩的嵌固深度保持不变、另一排桩的嵌固深度改变时,可将36%的桩长作为合理的嵌固深度;④连系梁使后桩的最大桩顶位移减小了15.6%,而对前桩的影响不大;⑤连系梁的存在降低了滑动面处的最大桩身弯矩,从而使得桩身弯矩分布更加合理。该研究成果有望为圆截面组合桩的设计提供借鉴和参考。 展开更多
关键词 滑坡加固 圆截面组合桩 加固机理 嵌固深度 物理模型试验
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基于势场增强烟花算法的二维全局路径规划
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作者 孙鹏耀 黄炎焱 王凯生 《兵工学报》 EI CAS CSCD 北大核心 2024年第10期3499-3518,共20页
高质量路径是未来无人自主作战的重要前提,针对复杂障碍环境下路径规划问题,提出基于势场增强烟花算法(Potential-field Enhanced Fireworks Algorithm,PEFWA)的路径规划方法。建立规划空间模型与动态维数路径描述模型,设立包含可行性... 高质量路径是未来无人自主作战的重要前提,针对复杂障碍环境下路径规划问题,提出基于势场增强烟花算法(Potential-field Enhanced Fireworks Algorithm,PEFWA)的路径规划方法。建立规划空间模型与动态维数路径描述模型,设立包含可行性因素与长度因素的目标函数,将路径规划问题转化为最优化问题;设计动态维数烟花初始化与维度增删操作,使相邻维度个体满足距离约束;提出基于障碍空间信息的爆炸幅度计算方法和连续维度选择方法,生成改进爆炸火花,提高全局搜索能力;引入势场引导策略,生成势场增强爆炸火花,让所选维度在合力方向上多次搜索,提高局部优化能力;采用交叉组合策略生成变异火花,并对超出规划空间的维度个体进行删减操作,提高多样性烟花高效产生能力;提出基于余弦相似度的双层锦标赛选择策略,提高烟花特征延续能力。采用相同基准函数,将PEFWA与烟花算法(Fireworks Algorithm,FWA)、粒子群优化(Particle Swarm Optimization,PSO)算法、遗传算法(Genetic Algorithm,GA)进行对比。研究结果表明:PEFWA的优化性能更强;在相同复杂障碍环境下进行多次路径规划仿真实验,验证了PEFWA中各个模块的有效性,与PSO算法、GA、A*算法相比,PEFWA在规划成功率、路径长度、路径光滑度、结果鲁棒性等方面均有优势;PEFWA在二维全局路径规划问题上具有有效性与优越性。 展开更多
关键词 全局路径规划 烟花算法 势函数 动态维数 交叉组合
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泌阳凹陷井楼八区低序级断层识别及其应用
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作者 陈玲 《石化技术》 CAS 2024年第2期184-186,共3页
泌阳凹陷井楼八区发育较多低序级断层,常规技术难以识别,在地层精细对比的基础上,运用井间地震资料联合、地震等时切片及油藏动态分析等技术,精细刻画了20m以下低序级断层产状,为注采调整提供地质依据。
关键词 地层对比 低序级断层 井震联合 断面图 微构造
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