Identification of forensically important fly eggs using a potassium permanganate staining technique

Fly eggs found in corpses can be utilized as entomological evidence in forensic investigations of deaths if the species of fly and the developmental rate at a temperature similar to the death scene are known. The species identification of fly eggs is particularly important, and previously, scanning electron microscope has been used for this purpose. Herein, we report a simple technique, using light microscopy, to identify forensically important eggs of Chrysomya rufifacies (Macquart), Chrysomya megacephala (Fabricius), Chrysomya pacifica Kurahashi, Chrysomya nigripes Aubertin, Aldrichina grahami (Aldrich), Lucilia cuprina (Wiedemann), Musca domestica L. and Megaselia scalaris (Loew). A 1% potassium permanganate solution was used to stain egg surfaces for 1 min, followed by dehydration in 15, 70, and 95%, absolute alcohol (each solution for 1 min) and the eggs were permanently mounted. The characteristics are based on the width of plastron, morphology of plastron area surrounding the micropyle and chorionic sculpturing, with the length of egg being used as supplemental feature.     

Identification of fly eggs using scanning electron microscopy for forensic investigations

Forensic entomology is the science that studies the role of insects in decomposing corpses and one of the most common uses is to estimate the post-mortem interval (PMI) based on insect activity on a decomposing body. Usually, flies are the first insects to reach a carcass and are able to oviposit on carrion within a few hours after death. Scanning electron microscopy (SEM) gives detailed information about morphological characters helping to identify the immature forms of flies and consequently serves as a tool in crime scene investigations. Sometimes, only eggs and larvae are found in corpses. Some dipteral species are important because their larvae develop in organic matter. The aim of this study is to identify eggs of species of forensic importance, such as Chrysomya megacephala, Chrysomya putoria, Lucilia cuprina, Lucilia eximia and Ophyra aenescens, using scanning electron microscopy (SEM). C. megacephala had no anastomosis or holes at the top of the islands and C. putoria had few anastomoses and no holes, whereas L. eximia and O. aenescens were found to have anastomoses and holes and L. cuprina had only anastomoses. The median area was bifurcated anteriorly in C. megacephala, L. eximia and O. aenescens and rounded in C. putoria and L. cuprina. Also the sculptures observed in the chorionic cells, the length and the way that median area ends up posteriorly are characteristics of great diagnostic value to identify muscoids of forensic importance.     

PROFILES OF INFLATED SURFACES

We study the shape of inflated surfaces introduced in [3] and [12]. More precisely, we analyze profiles of surfaces obtained by inflating a convex polyhedron, or more generally an almost everywhere flat surface, with a symmetry plane. We show that such profiles are in a one-parameter family of curves which we describe explicitly as the solutions of a certain differential equation.     

Micro-structure and frictional characteristics of beetle''s joint

Geometric and micro-structure design, tribology properties of beetle joints were experimentally studied, which aimed to enlighten ideas for the joint design of MEMS.The observation by using SEM and microscopy suggested that beetle's joints consist of a concave surface matched with a convex surface. The heads of the beetles, rubbing with flat glass, were tested in fresh and dried statuses and compared with sapphire ball with flat glass. Frictional coefficient of the joint material on glass was significantly lower than that of the sapphire sphere on glass. The material of the joint cuticle for convex surface is rather stiff (the elastic modulus 4.5 Gpa) and smooth. The surface is hydrophobic (the contact angle of distilled water was 88.3° ). It is suggested here that the high stiffness of the joint material and hydrophobicity of the joint surface are parts of the mechanism minimizing friction in insect joints.     

Micro-structure and frictional characteristics of beetle’s joint

Geometric and micro-structure design, tribology properties of beetle joints were experimentally studied, which aimed to enlighten ideas for the joint design of MEMS. The observation by using SEM and microscopy suggested that beetle’s joints consist of a concave surface matched with a convex surface. The heads of the beetles, rubbing with flat glass, were tested in fresh and dried statuses and compared with sapphire ball with flat glass. Frictional coefficient of the joint material on glass was significantly lower than that of the sapphire sphere on glass. The material of the joint cuticle for convex surface is rather stiff (the elastic modulus 4.5 Gpa) and smooth. The surface is hydrophobic (the contact angle of distilled water was 88.3°). It is suggested here that the high stiffness of the joint material and hydrophobicity of the joint surface are parts of the mechanism minimizing friction in insect joints.     

Thermal lens compensation by convex deformation of a flat mirror with variable annular force

An optical surface with convex parabolic shape over a large area has been created using a 12.7-mm-diameter annular pusher to deform a flat 25.4-mm-diameter mirror. The deformable mirror assembly has been modeled using finite element analysis software as well as analytical solutions. The measured parabolic surface deformation shows good agreement with those models. Mirror performance was studied using a Shack–Hartman wavefront sensor and the mirror has been applied to compensate thermal lensing in a Nd:YAG rod amplifier. PACS 41.85.Ct; 42.60.Da     

Ultrastructural and cytochemical aspects of Schistosoma mansoni cercaria

An alternative to identify the critical processes necessary to the parasite establishment of the host is to focus on the evolutionary stage responsible for the primary invasion, i.e. the infection structure. The objective of this study was to ultrastructurally characterize Schistosoma mansoni cercariae, using cytochemical techniques. In order to identify basic proteins, techniques such as ethanolic phosphotungstic acid (EPTA) and ammoniacal silver staining were used. Calcium sites location was achieved using the Hepler technique and to evidence anionic groups, we used cationic ferritin particles and enzyme treatment with trypsin Vibrio cholerae, chondroitinase and neuraminidase. The EPTA technique highlighted the presence of basic tegument proteins, nucleus and nucleolus from subtegumental cells, inclusion bodies and preacetabular glands. After using ammoniacal silver, we observed a strong staining in all infective larvae, particularly in the nuclei of muscle cells, circular muscle tissue and preacetabular glands. Calcium site locations were shown to be uniform, thereby limiting the inner spaces of the larvae, especially muscle cells. Samples treated with cationized ferritin particles presented strong staining at the cuticular level. Neuraminidase treatment did not alter the stained shape of such particles on the trematode surface. However, trypsin or chondroitinase treatment resulted in absence of staining on the larval surface. This information on the biochemical composition of the infecting S. mansoni larvae provides data for a better understanding of the biology of this parasite and background on the intriguing parasite–host relationship.     

First evidence of an intimate symbiotic association between fungi and larvae in basal attine ants

The most conspicuous ants in all of tropical America are those that belong to the tribe Attini which cultivate fungus. The objective of the present study is to verify the alterations that occur in the cuticle of the worker larvae from Myrmicocrypta, Mycetarotes and Trachymyrmex with the purpose of trying to establish the degree of this association. Attine ants from the Atta genus were used as a control group. The analysis of histological sections showed results about the distribution of the cells and tissues on the epidermis of A. sexdens rubropilosa ant larvae and Mycetarotes parallelus, Trachymyrmex fuscus and Myrmicocrypta sp. A cuticle covering the ants was observed in the larvae of all the species, and this is formed by a simple cubic epithelium, whose cells possibly change its shape to prismatic, depending on their secretory activity. Just under this epithelium large adipose cells with reserve granules in their cytoplasm were found. The presence of a space filled by granulose and acellular material was also observed, indicating that the larvae were in a molt period. The presence of fungal hyphae is observed both on the external side of the basal attine larvae as well as emitting projections to the interior of the cuticle reaching the epithelium and the adipocyte cells. Data obtained in the present study demonstrated that the fungus deposited on the surface of immature ants from attine basal species maintain a close relationship with them, once the fungus hyphae have the ability to disorganize the cuticle lamellas, penetrating the interior of the insect cells through the emission of prolongations transporting the cuticle and epithelium barriers and making substances exchanges between larvae and fungus.     

平凸型氮化硅球面微透镜的研究

介绍了用激光化学汽相沉积球面微透镜的技术，首先对激光化学汽相沉积法获得球面微透镜进行了理论分析，并用计算机分析了在一定沉积技术下的微透镜厚度剖面形状及光学聚集特性。其后介绍了激光化学汽相沉积的实验装置，用该装置在平面石英玻璃衬底上，制出了平凸型氮化硅球面微透镜，并对其参量进行了测量。     

Flat band in the core of topological defects: Bulk-vortex correspondence in topological superfluids with Fermi points

We discuss the dispersionless spectrum with zero energy in the linear topological defects—vortices. The flat band emerges inside the vortex living in the bulk medium containing topologically stable Fermi points in momentum space. The boundaries of the flat band in the vortex are determined by projections of the Fermi points in bulk to the vortex axis. This bulk-vortex correspondence for flat band is similar to the bulk-surface correspondence discussed earlier in the media with topologically protected lines of zeroes. In the latter case the flat band emerges on the surface of the system, and its boundary is determined by projection of the bulk nodal line on the surface.     

Some morphological aspects of Wuchereria bancrofti uterus after treatment with diethylcarbamazine

Confocal and EM analyses revealed that some female Wuchereria bancrofti, obtained from volunteers that received recommended diethylcarbamazine dose regimens, showed few or no embryos. Furthermore, inside the gravid uterus of female W. bancrofti treated with DEC we observed a finely granular, electron-dense material organised as strings of pearls, approximately 70 nm in maximal length surrounding intra-uterine microfilariae and apparently secreted by the embryo. Over the eggshells a similar material was also observed, possibly secreted by the uterine wall. The surface of intra-uterine microfilariae presented a material with identical electron-density to the scattered structures observed inside the egg. Similarly, the sheath of blood microfilariae of W. bancrofti also showed electron-dense projections, with shape and size similar to that observed inside the uterus.     

The applicability of thermodynamic perturbation theory to the evaluation of the specific excess free energy and disjoining pressure in a wetting layer of nonpolar liquid with convex interface

The specific excess free energy and disjoining pressure in a wetting layer of nonpolar liquid on the surface of a solid spherical particle have been calculated on the basis of thermodynamic perturbation theory. The calculation results are compared with the data for a flat interface, obtained both experimentally and within the quasi-thermodynamic approach. The stability of the liquid layer on the convex surface is analyzed using the concept of reduced disjoining pressure.     

Ultrafocusing of surface plasmon-polariton in a narrowing concave gap

In a concave gap between flat and cylindrically convex metallic surfaces, surface plasmon-polariton may be localized in nanoscale in conditions of adiabatic narrowing of the gap minimum width and convex curvature radius. Waveguide channels of this type may serve, due to small losses, as an elemental basis for creation of high-speed nanoscale optical circuits.     

极大口径光学望远镜凸非球面副镜的补偿检测法研究

提出了一种检测大口径、快焦比凸双曲面反射镜的补偿检验方法,补偿系统由一组小透镜和一块大口径反射标准镜组成,标准镜的口径约为被检验镜的1.8倍,该方法为极大口径光学望远镜凸非球面副镜的检验提供了一种有效的解决方案。以美国30 m望远镜（TMT）3.1 m,F/1的凸双曲面副镜为例,进行了补偿光路的设计优化。设计结果表明,该方法可以直接检测到直径达3.1 m的大口径、快焦比凸双曲面副镜的整个表面质量,补偿系统像差被校正得很好,PV值约为/100,弥散斑直径在衍射极限范围内。     

̀Spatial impulse response of a rectangular double curved transducer

Calculation of the pressure field from transducers with both a convex and a concave surface geometry is a complicated assignment that often is accomplished by subdividing the transducer surface into smaller flat elements of which the spatial impulse response is known. This method is often applied to curved transducers because an analytical solution is unknown. In this work a semi-analytical algorithm for the exact solution to a first order in diffraction effect of the spatial impulse response of rectangular-shaped double curved transducers is presented. The solution and an approximation to it are investigated. The approximation reformulates the solution to an analytically integrable expression, which is computationally efficient to solve. Simulation results are compared to FIELD II simulations. Calculating the response from 200 different points yields a mean error for the different approximations ranging from 0.03% to 0.8% relative to a numerical solution for the spatial impulse response. It is also shown that the presented algorithm gives consistent results with FIELD II for a linear flat, a linear focused, and a convex nonfocused element. The solution involved a three-point Taylor expansion and gave an accuracy of 0.01%.     

The flattening of the average potential in models with fermions

The average potential is a scale dependent scalar effective potential. In a phase with spontaneous symmetry breaking its inner region becomes flat as the averaging extends over infinite volume and the average potential approaches the convex effective potential. Fermion fluctuations affect the shape of the average potential in this region and its flattening with decreasing physical scale. They have to be taken into account to find the true minimum of the scalar potential which determines the scale of spontaneous symmetry breaking.     

Absolute surface form measurement of flat optics based on oblique incidence method

In this Letter, a test method based on oblique incidence is practically implemented in the interferometric measurement process. Three sets of wavefront data are achieved through cavity interference measurement with a Fizeau interferometer and one oblique incidence measurement. An iterative algorithm is applied to retrieve the absolute surface shape of the test flat. By adding two sets of measurements, the absolute surface error of the interferometer's reference flat can be obtained. The new method can not only calibrate the reference flat error of interferometer, but also provide the absolute measurement method for high precision optical components applied in high power laser systems.     

Ultrastructure of eggs of Paracapillaria (Crossicapillaria) philippinensis and evidence related to its life cycle

The varied ultrastructure of the eggshell of Paracapillaria (Crossicapillaria) philippinensis, collected from a human sample, is reported from a scanning electron microscopy study. Two distinct egg shapes were identified: typical peanut-shaped and swollen peanut-shaped. Both thick and thin eggshells were detected. Thick eggshells are either fairly smooth or bear a beam-like network in relation to the pillars in their surface ultrastructure. Thin eggshells are transparent allowing visibility of the coiled larva within. Presence of the thin shell provides supportive evidence of autoinfection involved in the life cycle of this medically important parasite.     

磷化铟单晶生长中的传热和流动分析

用有限元法对轴向磁场存在下3英寸磷化铟单晶液封提拉法生长中的传热和流动进行了求解．结果表明:液封改变了晶体表面被封部分的换热,进而影响生长界面的形状．增加磁场强度能有效减弱熔体和封层内的流动,并使生长界面形状发生变化。增加提拉速度,生长界面形状由凸变凹．随晶体转速的增加,多涡胞流动出现．     

Diffraction of a two-shock configuration by a convex cylindrical surface

The subject of this work is numerical investigation into the diffraction of a shock-wave configuration by a convex cylindrical surface. The diffraction is a stage of interaction of a shock wave with a two-dimensional body. It is preceded by the stage of shock wave reflection from the front surface of the body, the back surface of which has a convex cylindrical shape. The two-or three-shock configuration formed on the front surface diffracts by the back cylindrical surface. The emphasis is on studying the diffraction of the two-shock wave configuration with the diffraction angle varying continuously. The object under study a wedge with an inclined front surface and convex cylindrical back surface. The results of numerical investigation are obtained by integrating the Euler equations. Flow features associated with the simultaneous diffraction of the incident and reflected shock waves are revealed. The evolution of the gasdynamic system (stagnation wave + TU layer) arising inside the diffraction area is studied. Breakaway and vorticity initiation are considered. It is shown that the positions of the line of separation and TU layer change in the course of diffraction. They merge together at the stage of steady flow. Comparison is made between the flow formed upon diffraction of the two-shock configuration by the cylindrical surface and the flow generated upon diffraction by horizontal and vertical surfaces.