化工院校情报工作者的一次聚会

<正> 全国化工院校情报中心站第四届年会于1988年10月17日-21日在武汉化工学院召开。中心站21个成员单位的代表出席了会议。化工部情报所的有关同志参加了会议。湖北省及武汉市图书馆情报界的知名人士、武汉化工学院领导等均到会致词祝贺。年会的主要议程有:一、就高校情报工作的服务方向、情报有偿服务、情报教学等方面的改革进行了广泛的交流和探讨。华东化工学院和青岛化工学院的代表介绍了图书馆实行定编定岗、优化组合、工资包干和情报实行定额承包、面向企业的改革尝试,引起了代表们的极大兴趣和热烈讨论。     

Association of Aberrations in One Carbon Metabolism with Intimal Medial Thickening in Patients with Type 2 Diabetes Mellitus

The present work was aimed to study the association of one carbon genetic variants, hyperhomocysteinemia and oxidative stress markers, i.e., serum nitrite, plasma malondialdehyde (MDA) and glutathione (GSH) on intimal medial thickening (IMT) in patients with type 2 diabetes mellitus (T2D). A total number of 76 subjects from ACS Medical College and Hospital, Chennai, India were included in the study, i.e., Group I (n = 42) of T2D and Group II (n = 34) of age- and sex matched healthy controls. The glycated haemoglobin was measured by ion-exchange resin method; plasma homocysteine by Enzyme Linked Immunosorbant Assay method; serum nitrite (nitric oxide, NO), plasma MDA and GSH by spectrophotometric methods; the IMT by high frequency ultrasound. The polymorphisms of one carbon genetic variants were genotyped using polymerase chain reaction-restriction fragment length polymorphism and amplified fragment length polymorphism methods. Results indicate that methyltetrahydrofolate homocysteine methyl transferase (MTR) A2756G allele was found to be protective in T2D and the other variants were not significantly associated with T2D. Glutamate carboxypeptidase II (GCP II) C1561T (r = 0.34; p = 0.05) and methylene tetrahydrofolate reductase (MTHFR) C677T (r = 0.35; 0.04) showed positive correlation with plasma homocysteine in T2D cases. In this study, MTR A2756G allele was found to be protective in T2D; GCP II C1561T and MTHFR C677T showed positive association with plasma homocysteine in T2D cases. Among all the genetic variants, MTR A2756G was found influence IMT. RFC 1 G80A and TYMS 5′-UTR 2R3R showed synergistically interact with MTR A2756G in influencing increase in IMT.     

Quantitative detection of cells expressing BlaC using droplet-based microfluidics for use in the diagnosis of tuberculosis

This paper describes a method for the quantitative detection of cells expressing BlaC, a β-lactamase naturally expressed by Mycobacterium tuberculosis, intended for the diagnosis of tuberculosis. The method is based on the compartmentalization of bacteria in picoliter droplets at limiting dilutions such that each drop contains one or no cells. The co-encapsulation of a fluorogenic substrate probe for BlaC allows the quantification of bacteria by enumerating the number of fluorescent drops. Quantification of 10 colony forming units per milliliter is demonstrated. Furthermore, the encapsulation of single cell in drops maintains the specificity of the detection scheme even when the concentration of bacteria that do not express BlaC exceeds that expressing BlaC by one million-fold.     

Disrupting the wall accumulation of human sperm cells by artificial corrugation

Many self-propelled microorganisms are attracted to surfaces. This makes their dynamics in restricted geometries very different from that observed in the bulk. Swimming along walls is beneficial for directing and sorting cells, but may be detrimental if homogeneous populations are desired, such as in counting microchambers. In this work, we characterize the motion of human sperm cells ∼60 μm long, strongly confined to ∼25 μm shallow chambers. We investigate the nature of the cell trajectories between the confining surfaces and their accumulation near the borders. Observed cell trajectories are composed of a succession of quasi-circular and quasi-linear segments. This suggests that the cells follow a path of intermittent trappings near the top and bottom surfaces separated by stretches of quasi-free motion in between the two surfaces, as confirmed by depth resolved confocal microscopy studies. We show that the introduction of artificial petal-shaped corrugation in the lateral boundaries removes the tendency of cells to accumulate near the borders, an effect which we hypothesize may be valuable for microfluidic applications in biomedicine.     

Effects of forward trunk lean on hamstring muscle kinematics during sprinting

This study aimed to investigate the effects of forward trunk lean on hamstring muscle kinematics during sprinting. Eight male sprinters performed maximal-effort sprints in two trunk positions: forward lean and upright. A three-dimensional musculoskeletal model was used to compute the musculotendon lengths and velocity of the biceps femoris long head, semitendinosus, and semimembranosus muscles during the sprinting gait cycle. The musculotendon lengths of all the three hamstring muscles at foot strike and toe-off were significantly greater during the forward trunk lean sprint than during the upright trunk sprint. In addition, a positive peak musculotendon lengthening velocity was observed in the biceps femoris long head and semimembranosus muscles during the late stance phase, and musculotendon lengths at that instant were significantly greater during the forward trunk lean sprint than during the upright trunk sprint. The present study provides significant evidence that a potential for hamstring muscle strain injury involving forward trunk lean sprinting would exist during the stance phase. The results also indicate that the biceps femoris long head and semimembranosus muscles are stretched during forward trunk lean sprinting while contracting eccentrically in the late stance phase; thus, the elongation load on these muscles could be increased.     

Core-shell hydrogel beads with extracellular matrix for tumor spheroid formation

Creating multicellular tumor spheroids is critical for characterizing anticancer treatments since they may provide a better model of the tumor than conventional monolayer culture. Moreover, tumor cell interaction with the extracellular matrix can determine cell organization and behavior. In this work, a microfluidic system was used to form cell-laden core-shell beads which incorporate elements of the extracellular matrix and support the formation of multicellular spheroids. The bead core (comprising a mixture of alginate, collagen, and reconstituted basement membrane, with gelation by temperature control) and shell (comprising alginate hydrogel, with gelation by ionic crosslinking) were simultaneously formed through flow focusing using a cooled flow path into the microfluidic chip. During droplet gelation, the alginate acts as a fast-gelling shell which aids in preventing droplet coalescence and in maintaining spherical droplet geometry during the slower gelation of the collagen and reconstituted basement membrane components as the beads warm up. After droplet gelation, the encapsulated MCF-7 cells proliferated to form uniform spheroids when the beads contained all three components: alginate, collagen, and reconstituted basement membrane. The dose-dependent response of the MCF-7 cell tumor spheroids to two anticancer drugs, docetaxel and tamoxifen, was compared to conventional monolayer culture.     

题目：一种支持产品平台设计的多准则模块划分方法

目的：研究多准则约束下的产品模块划分方法,为企业建立稳健的模块化产品平台奠定基础。方法：采用改进的多目标进化算法对建立的多准则模块划分数学模型求解,并采用模糊集合评价机制进行最优解的寻取,得到基于多准则模块划分方法的产品模块划分结果。结论：通过改进的多目标进化算法求解多准则模块划分模型,能够得到有效支持产品平台设计的产品模块划分方案。通过与已有优化方法的比较验证了本文提出的多准则模块划分方法的优越性。     

Relationship Reciprocation Modulates Resource Allocation in Adolescent Social Networks: Developmental Effects

Adolescence is characterized as a period of social reorientation toward peer relationships, entailing the emergence of sophisticated social abilities. Two studies (Study 1: N = 42, ages 13–17; Study 2: N = 81, ages 13–16) investigated age group differences in the impact of relationship reciprocation within school‐based social networks on an experimental measure of cooperation behavior. Results suggest development between mid‐ and late adolescence in the extent to which reciprocation of social ties predicted resource allocation. With increasing age group, investment decisions increasingly reflected the degree to which peers reciprocated feelings of friendship. This result may reflect social‐cognitive development, which could facilitate the ability to navigate an increasingly complex social world in adolescence and promote positive and enduring relationships into adulthood.