计算电磁学进展及其在现代电机优化设计中的应用

首先总结了近年来计算电磁学取得的重要成果,阐述了现代电机设计中的新型算法及其在电机设计中的应用,以及电机设计优化方向,并对计算电磁学未来的发展对推动电机优化设计的作用作了展望。     

儿童遗传代谢性肝病的超微病理学观察

目的:观察儿童遗传代谢性肝病的肝组织超微病理学改变特征,结合临床资料探讨电镜检查在诊断该类疾病中的作用.方法:收集2016年7月-2020年10月以肝大、肝功能不良等为主要临床表现,临床怀疑为遗传代谢性肝病的72例肝穿刺活检标本,电镜观察肝组织的超微结构改变.结果:遗传代谢性肝病患儿均有不同程度的肝大、肝酶升高等表现....     

遗传性球形红细胞增多症的扫描电镜诊断

目的：为探讨遗传性球形红细胞增多症异形红细胞的形态分类,发生演变,发病机理和诊断及鉴别,本文运用扫描电镜技术对遗传性球形红细胞增多症的血工细胞进行研究。方法：５例遗传性球形红细胞增多症患者及２例农系成员的静脉血经抗凝和固定,离心和漂洗,干燥和喷金后置于扫描电镜下观察。结果：在观察红细胞从盘形到口形,最终至球形的过程中,作者对各型红细胞直径和中央凹陷直径及细胞厚度的变化作了测量,并结合细胞表面形态和     

Inherited Thrombophilia in the Era of Direct Oral Anticoagulants

Severe inherited thrombophilia includes rare deficiencies of natural anticoagulants (antithrombin and proteins C and S) and homozygous or combined factor V Leiden and FII G20210A variants. They are associated with a high thrombosis risk and can impact the duration of anticoagulation therapy for patients with a venous thromboembolism (VTE) event. Therefore, it is important to diagnose thrombophilia and to use adapted anticoagulant therapy. The widespread use of direct anticoagulants (DOACs) for VTE has raised new issues concerning inherited thrombophilia. Concerning inherited thrombophilia diagnosis, DOACs are directed toward either FIIa or FXa and can therefore interfere with coagulation assays. This paper reports DOAC interference in several thrombophilia tests, including the assessment of antithrombin, protein S, and protein C activities. Antithrombin activity and clot-based assays used for proteins C and S can be overestimated, with a risk of missing a deficiency. The use of a device to remove DOACs should be considered to minimize the risk of false-negative results. The place of DOACs in the treatment of VTE in thrombophilia patients is also discussed. Available data are encouraging, but given the variability in thrombosis risk within natural anticoagulant deficiencies, evidence in patients with well-characterized thrombophilia would be useful.     

Homologous Recombination Deficiencies and Hereditary Tumors

Homologous recombination (HR) is a vital process for repairing DNA double-strand breaks. Germline variants in the HR pathway, comprising at least 10 genes, such as BRCA1, BRCA2, ATM, BARD1, BRIP1, CHEK2, NBS1(NBN), PALB2, RAD51C, and RAD51D, lead to inherited susceptibility to specific types of cancers, including those of the breast, ovaries, prostate, and pancreas. The penetrance of germline pathogenic variants of each gene varies, whereas all their associated protein products are indispensable for maintaining a high-fidelity DNA repair system by HR. The present review summarizes the basic molecular mechanisms and components that collectively play a role in maintaining genomic integrity against DNA double-strand damage and their clinical implications on each type of hereditary tumor.     

Economic trade-offs between genetic improvement and longevity in dairy cattle

Genetic improvement in sires used for artificial insemination (AI) is increasing faster compared with a decade ago. The genetic merit of replacement heifers is also increasing faster and the genetic lag with older cows in the herd increases. This may trigger greater cow culling to capture this genetic improvement. On the other hand, lower culling rates are often viewed favorably because the costs and environmental effects of maintaining herd size are generally lower. Thus, there is an economic trade-off between genetic improvement and longevity in dairy cattle. The objective of this study was to investigate the principles, literature, and magnitude of these trade-offs. Data from the Council on Dairy Cattle Breeding show that the estimated breeding value of the trait productive life has increased for 50 yr but the actual time cows spend in the herd has not increased. The average annual herd cull rate remains at approximately 36% and cow longevity is approximately 59 mo. The annual increase in average estimated breeding value of the economic index lifetime net merit of Holstein sires is accelerating from $40/yr when the sire entered AI around 2002 to $171/yr for sires that entered AI around 2012. The expectation is therefore that heifers born in 2015 are approximately $50 more profitable per lactation than heifers born in 2014. Asset replacement theory shows that assets should be replaced sooner when the challenging asset is technically improved. Few studies have investigated the direct effects of genetic improvement on optimal cull rates. A 35-yr-old study found that the economically optimal cull rates were in the range of 25 to 27%, compared with the lowest possible involuntary cull rate of 20%. Only a small effect was observed of using the best surviving dams to generate the replacement heifer calves. Genetic improvement from sires had little effect on the optimal cull rate. Another study that optimized culling decisions for individual cows also showed that the effect of changes in genetic improvement of milk revenue minus feed cost on herd longevity was relatively small. Reduced involuntary cull rates improved profitability, but also increased optimal voluntary culling. Finally, an economically optimal culling model with prices from 2015 confirmed that optimal annual cull rates were insensitive to heifer prices and therefore insensitive to genetic improvement in heifers. In conclusion, genetic improvement is important but does not warrant short cow longevity. Economic cow longevity continues to depends more on cow depreciation than on accelerated genetic improvements in heifers. This is confirmed by old and new studies.     

基于惩罚域的同步优化方法

讨论了基于惩罚域的遗传算法对神经网络结构和权值同步优化方法。并通过实验仿真将该方法与BP算法进行比较，从而验证了该方法的可行性与有效性。     

产量构成非线性优化模型的研究与应用

将油田产量构成分解为9部分，以总产量的利润之和最大为最优目标，以平均吨油成本不大于规定成本作为成本约束条件，以各产量部分投资之和不超过总投资作为投资约束条件，以9个决策变量要满足其上下限为决策变量约束条件，建立了产量构成非线性优化模型，可用于求得规划期内每年总产量和各部分产量及其成本、利润等指标。应用油田开发历史数据，用带有外部激励的自回归滑动平均模型预测优化模型参数，用最小二乘法多项式拟合产量与工作量之间的非线性关系，用遗传算法求解非线性模型。对某油田产量构成非线性优化结果符合该油田的实际。     

L-fuzzy闭包空间的T1与T2分离性

研究了L-fuzzy闭包空间的T1与T2分离性．首先定义了L-fuzzy闭包空间的L与T2分离性的概念，其次用类比、推广的方法讨论了T，与丁2分离性的遗传性，可乘性等性质．证明了一个T1（resp．T2）L-fuzzy闭包空间的子空间仍是T1（resp．，T2）L-fuzzy闭包空间，一族T1（resp．，T2）L-fuzzy闭包空间的乘积空间仍是T1（resp．，T2）L-fuzzy闭包空间的结果．这些结果表明定义的L-fuzzy闭包空间的T1与T2分离性具有遗传性，可乘性．     

基于遗传神经网络的公路工程造价估算分析

从影响公路造价的影响因素中提取特征因子为参数,用历史数据为依据,用遗传神经网络建立了公路造价快速估测模型,最后用实例验证了遗传神经网络模型在公路工程造价估测中的优良效果。