Simulation of shape variation of projectile nose during high-speed penetration into concrete

A formula is developed to estimate the total mass loss of projectile, based on the assump- tions that the peeling of molten surface layer in projectile nose is the primary cause of mass loss, and the frictional heat is totally absorbed by the projectile. Extrapolating this formula to predict the mass loss of local area of projectile, the receding displacement on projectile surface is obtained, which is vertical to the symmetry axis of projectile. Thereby, a finite difference method model is constructed to simulate the variation of projectile shape. The shape of residual projectile, depth of penetration of projectile and its mass loss obtained by calculation are found in good consistency with respective experimental data.

Impact of environmental factors on the body shape variation and sexual shape dimorphism in Carabus granulatus L.(Coleoptera:Carabidae)

Despite plenty of data in insects shape variation, papers on environmental factors effect on such variation are scarce and in ground beetles are practically absent. The aim of this research was to： （i） model the effect of the region of habitation, urbanization and habitat vegetation into the shape variation in widespread carabid species; （ii） describe sexual shape dimorphism in studied species. Samples were pitfall trapped in different regions of its area in the spectrum of anthropogenic influence （cities, suburbs, natural biotopes）. One thousand and one hundred sixty-eight specimens were analyzed for six morphometric traits and terminal points of those measurements were used as landmarks for Procrustes analysis. We used linear models to reveal which factor （region, urbanization or vegetation） and in what direction affected beetles shape. Results showed that males in C. granulatus had more convex elytra and head, and the more convex in apical-basal direction pronotum. In its area from the east to the west elytra flattened in medial-distal direction and pronotum flattened in apical-distal direction. In disturbed urban environment beetles pronotum became more convex in both sexes and males elytra became more convex too. In open habitats （meadows, lawns） beetles became more flattened.

Particle shape characterisation and classification using automated microscopy and shape descriptors in batch manufacture of particulate solids

It is known that size alone, which is often defined as the volume-equivalent diameter, is not sufficient to characterize many particulate products. The shape of crystalline products can be as important as size in many applications, Traditionally, particulate shape is often defined by several simple descriptors such as the maximum length and the aspect ratio. Although these descriptors are intuitive, they result in a loss of information about the original shape. This paper presents a method to use principal component analysis to derive simple latent shape descriptors from microscope images of particulate products made in batch processes, and the use of these descriptors to identify batch-to-batch variations. Data from batch runs of both a laboratory crystalliser and an industrial crystallisation reactor are analysed using the described approach. Qualitative and quantitative comparisons with the use of traditional shape descriptors that have nhwical meanings and Fourier shape descriptors are also made.

Host evolution in Mastomys natalensis(Rodentia:Muridae):An integrative approach using geometric morphometrics and genetics

The commensal rodent Mastomys natalensis is the natural reservoir of Lassa arenavirus(LASV),which causes hemorrhagic fever in West Africa.To study a possible effect of the virus on phenotypic and genotypic variation of its persistently infected host,we compared LASV-positive and non-infected wild-caught M.natalensis.The LASV effects on the phenotypic variation were explored using standard external morphometric measurements,geometric morphometric analyses of the cranial size and shape,and brain case volume.The genetic variability of M.natalensis specimens was assessed using 9 polymorphic microsatellite markers.Independent of sex and age,LASV-infected animals had smaller external body measurements,reproductive organs,skull size and brain case volume.Cranial shape differences between the 2 groups are represented by a lateral constriction of the entire skull.The genetic variability revealed consanguinity only among the LASV-positive rodents.We hypothesize that growth impairment may result in a selective disadvantage for LASV-infected M.natalensis,leading to a preferably commensal lifestyle in areas where the LAVS is endemic and,thereby,increasing the risk of LASV transmission to humans.

鲁中地区2011—2013年流感嗜血杆菌耐药性分析

目的了解流感嗜血杆菌的检出情况,并对其耐药情况进行动态演变,分析与其相关的一系列因素,为基层医院尤其是鲁中地区的临床治疗提供合理、可靠的依据。方法收集我院2011——2013年1019例成人社区获得性肺炎患者痰培养检查中检出的38株流感嗜血杆菌,采用K-B纸片法进行药敏试验,采用头孢硝噻吩纸片定性试验测定被检测菌株的β内酰胺酶试验。结果从1019例社区获得性肺炎患者痰培养检查中检出38株流感嗜血杆菌,总分离率为3.7%。结论 38株流感嗜血杆菌中产β内酰胺酶检出率为26%,对四环素、左氧氟沙星、环丙沙星、阿莫西林等药物耐药率呈上升趋势(13%~26%)。其中以环丙沙星耐药率最高;对复方新诺明、庆大霉素耐药率最高,共检出21例,耐药率高达55%,对亚胺培南、美洛培南、头孢曲松、头孢噻肟、头孢呋辛等药物敏感,耐药率<8%。