Allelic exclusion in transgenic mice that express the membrane form of immunoglobulin mu

Antibody-producing cells display a special form of regulation whereby each cell produces immunoglobulin from only one of its two sets of antibody genes. This phenomenon, called allelic exclusion, is thought to be mediated by the product of one heavy chain allele restricting the expression of the other. Heavy chains are synthesized in two molecular forms, secreted and membrane bound. In order to determine whether it is specifically the membrane-bound form of the immunoglobulin M (IgM) heavy chain (mu) that mediates this regulation, transgenic mice were created that carry a human mu chain gene altered so that it can only direct the synthesis of the membrane-bound protein. The membrane-bound form of the human mu chain was made by most of the B cells in these animals as measured by assays of messenger RNA and surface immunoglobulins. Further, the many B cells that express the human gene do not express endogenous mouse IgM, and the few B cells that express endogenous mouse mu do not express the transgene. Thus, the membrane-bound form of the mu chain is sufficient to mediate allelic exclusion. In addition, the molecular structures recognized for this purpose are conserved between human and mouse systems.     

Large-Scale Synthesis of Aligned Carbon Nanotubes

Large-scale synthesis of aligned carbon nanotubes was achieved by using a method based on chemical vapor deposition catalyzed by iron nanoparticles embedded in mesoporous silica. Scanning electron microscope images show that the nanotubes are approximately perpendicular to the surface of the silica and form an aligned array of isolated tubes with spacings between the tubes of about 100 nanometers. The tubes are up to about 50 micrometers long and well graphitized. The growth direction of the nanotubes may be controlled by the pores from which the nanotubes grow.     

Applying Public Participation Geographic Information Systems to Wildlife Management

Wildlife management increasingly incorporates public participation to be more inclusive and reduce tensions between management and the general public in the decision-making process. There is also a need, however, to include spatial data since most wildlife biological and biophysical data are stored spatially in geographic information systems (GIS). This article presents a method for integrating this information using public participation geographic information systems (PPGIS). We asked stakeholders to identify specific places on a map that they would like to see maintained for the conservation of particular threatened species. This information is useful for identifying public wildlife management preferences and for allowing comparisons between public and expert opinions. We found high levels of public accuracy in identifying suitable habitat for threatened species conservation. We also identified places of potential conflict due to incompatible stakeholder preferences, but found little conflict between public conservation and development preferences.     

Expression and Localization of Vascular Endothelial Growth Factor and its Receptors in the Corpus Luteum During Oestrous Cycle in Water Buffaloes (Bubalus bubalis)

The aim of this study was to document the expression and localization of VEGF system comprising of VEGF isoforms (VEGF 120, VEGF 164 and VEGF 188) and their receptors (VEGFR1 and VEGFR2) in buffalo corpus luteum (CL) obtained from different stages of the oestrous cycle. Real‐time RT‐PCR (qPCR), Western blot and immunohistochemistry were applied to investigate mRNA expression, protein expression and localization of examined factors. In general, all the components of VEGF system (the VEGF isoforms and their receptors) were found in the water buffalo CL during the oestrous cycle. The mRNA as well as protein expression of VEGF system was highest during the early and mid‐luteal phase, which later steadily decreased (p < 0.05) after day 10 to reach the lowest level in regressed CL. As demonstrated by immunohistochemistry, VEGF protein was localized predominantly in luteal cells; however, VEGFR1 and VEGFR2 were localized in luteal cells as well as in endothelial cells. In conclusion, the dynamics of expression and localization of VEGF system in buffalo corpora lutea during the luteal phase were demonstrated in this study, indicating the possible role of VEGF system in the regulation of luteal angiogenesis and proliferation of luteal as well as endothelial cells through their non‐angiogenic function.     

短脉纹石蛾属(毛翅目:纹石蛾科)广西3个新种记述

记述了广西短脉纹石蛾属3个新种,即刺尾短脉纹石蛾(Cheumatopsyche acanthus,n.sp.)、微凹短脉纹石蛾(C.concav-iuscula,n.sp.)和平尾短脉纹石蛾(C.orthocercata,n.sp.)。刺尾短脉纹石蛾与产于越南的金短脉纹石蛾(C.kimOláh&Jo-hanson)较为接近,但其第10节侧面观上下缘近平行,中叶呈尖刺状,侧叶明显宽于中叶;内茎鞘突长卵圆形;下附肢第2节细而直;可与后者区别。微凹短脉纹石蛾与产于福建的挂墩短脉纹石蛾(C.guadunicaLi)相似,但其第10节侧面观较长,约为其高的2倍;阳具腹面观由基部向端部逐渐变细,并在其最端部略加粗;阳具内茎鞘突侧面观近三角形;下附肢第2节侧面观基部2/3粗大,端部1/3细窄,并略向上弯曲,上缘具一细微凹切;可与后者区别。平尾短脉纹石蛾与产于越南的伊氏短脉纹石蛾(C.ecsediiOláh&Johanson)相似,但第10节侧面观略呈四边形;阳具侧面观内茎鞘突略呈四边形,且其下缘略向上切入;下附肢第2节明显窄于第1节端部;可与后者区别。模式标本保存于南京农业大学昆虫标本馆。     

Analysis of Yam Minisett technique adoption in Nigeria

White yam (Dioscorea rotundata Poir.) is an important tuber crop grown throughout West Africa, the Caribbean, and Latin America. Propagation of the crop is primarily vegetative, through the use of small whole tubers (seed yams) and cut pieces of tuber (setts) planted to produce the larger tubers (ware yams) that households consume and sell. The Yam Minisett Technique (YMT) was introduced in Nigeria in the late 1970s as a means of increasing the production of seed yams. The YMT is different from many other agricultural technologies in that it requires farmers to do something – cut their tubers into small pieces – which they feel based on experience is potentially damaging as it causes rot. Indeed, the existing literature suggests that adoption of the YMT tends to be low and variable. However, to date there has been no systematic analysis of the existing literature on YMT adoption designed to explore which factors are reported to be the most important and why. Hence, the objective of this paper is to analyze the YMT adoption studies published to date to explore which factors are particularly important, and how this may help guide future research in YMT adoption. The results suggest that uncertainty – risk and ambiguity aversion – as perceived by farmers is a key consideration in YMT adoption and needs to be considered in future work.