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81.
Asher Ornoy Maria Becker Liza Weinstein-Fudim Zivanit Ergaz 《International journal of molecular sciences》2021,22(6)
In spite of the huge progress in the treatment of diabetes mellitus, we are still in the situation that both pregestational (PGDM) and gestational diabetes (GDM) impose an additional risk to the embryo, fetus, and course of pregnancy. PGDM may increase the rate of congenital malformations, especially cardiac, nervous system, musculoskeletal system, and limbs. PGDM may interfere with fetal growth, often causing macrosomia, but in the presence of severe maternal complications, especially nephropathy, it may inhibit fetal growth. PGDM may also induce a variety of perinatal complications such as stillbirth and perinatal death, cardiomyopathy, respiratory morbidity, and perinatal asphyxia. GDM that generally develops in the second half of pregnancy induces similar but generally less severe complications. Their severity is higher with earlier onset of GDM and inversely correlated with the degree of glycemic control. Early initiation of GDM might even cause some increase in the rate of congenital malformations. Both PGDM and GDM may cause various motor and behavioral neurodevelopmental problems, including an increased incidence of attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). Most complications are reduced in incidence and severity with the improvement in diabetic control. Mechanisms of diabetic-induced damage in pregnancy are related to maternal and fetal hyperglycemia, enhanced oxidative stress, epigenetic changes, and other, less defined, pathogenic mechanisms. 相似文献
82.
如何通过金属监督质量管理的优化创新来更好地服务当前电力设备材料等级越来越高的需求,已经成为目前电力行业内金属监督质量管理工作面临的一项挑战性课题。文章主要分析了现阶段电力行业金属监督质量管理工作中普遍存在的问题、不足和难点,并明确金属监督质量管理工作的基本要求,最后提出了金属监督质量管理工作优化的相关措施,对电力行业金属监督质量管理工作提供有助益的参考。 相似文献
83.
高校扩招背景下大学生心理问题易发事件及其相关因素研究 总被引:3,自引:0,他引:3
本研究用高校学生心理问题调查问卷对 16 2 4名大学生进行调查 ,并用SCL - 90量表对其中 5 80名学生进行测评 ,同时测量学生的特质性应对方式 ,探讨高校扩招背景下大学生的心理问题易发事件及相关因素。扩招后大学生自感压力最大的心理问题易发事件是感到竞争激烈、择业困难、考试不过关等 ;大部分易发事件都和SCL - 90总分及各因子分存在着极显著相关 ;应对方式和易发事件及SCL - 90总分、各因子分存在着极显著的相关。扩招后和竞争、就业、学业相关的心理问题易发事件已成为影响大学生心理健康的首要因素 相似文献
84.
硫酸钾生产出现问题的机理分析及改进建议 总被引:3,自引:0,他引:3
曼海姆法硫酸钾生产装置出现 3个问题 :原料 KCl中有机碳的分析结果非常高 ;测定副产盐酸总酸度 ,加 1~ 2滴甲基橙不显红色 ;分析副产盐酸中 SO4 2含量超标 (≥ 0 .1% )。分析产生以上问题的原因并提出解决措施 相似文献
85.
The aim of the paper is to design high-order artificial boundary conditions for the Schrödinger equation on unbounded domains in parallel with a treatment of the heat equation. We first introduce a circular artificial boundary to divide the unbounded definition domain into a bounded computational domain and an unbounded exterior domain. On the exterior domain, the Laplace transformation in time and Fourier series in space are applied to achieve the relation of special functions. Then the rational functions are used to approximate the relation of the special functions. Applying the inverse Laplace transformation to a series of simple rational function, we finally obtain the corresponding high-order artificial boundary conditions, where a sequence of auxiliary variables are utilized to avoid the high-order derivatives in respect to time and space. Furthermore, the finite difference method is formulated to discretize the reduced initial–boundary value problem with high-order artificial boundary conditions on a bounded computational domain. Numerical experiments are presented to illustrate the performance of our method. 相似文献
86.
87.
《Expert systems with applications》2014,41(3):877-885
This paper describes a novel algorithm for numerical optimization, called Simple Adaptive Climbing (SAC). SAC is a simple efficient single-point approach that does not require a careful fine-tunning of its two parameters. SAC algorithm shares many similarities with local optimization heuristics, such as random walk, gradient descent, and hill-climbing. SAC has a restarting mechanism, and a powerful adaptive mutation process that resembles the one used in Differential Evolution. The algorithms SAC is capable of performing global unconstrained optimization efficiently in high dimensional test functions. This paper shows results on 15 well-known unconstrained problems. Test results confirm that SAC is competitive against state-of-the-art approaches such as micro-Particle Swarm Optimization, CMA-ES or Simple Adaptive Differential Evolution. 相似文献
88.
In this paper, a new constraint handling method based on a modified AEA (Alopex-based evolutionary algorithm) is proposed. Combined with a new proposed ranking and selecting strategy, the algorithm gradually converges to a feasible region from a relatively feasible region. By introduction of an adaptive relaxation parameter μ, the algorithm fully takes into account different functions corresponding to different sizes of feasible region. In addition, an adaptive penalty function method is employed, which adaptively adjust the penalty coefficient so as to guarantee a moderate penalty. By solving 11 benchmark test functions and two engineering problems, experiment results indicate that the proposed method is reliable and efficient for solving constrained optimization problems. Also, it has great potential in handling many engineering problems with constraints, even with equations. 相似文献
89.
90.