From robustness to resilience: A network Price identity approach

We model a closed-loop network of agents distributed among subnetworks and study the sustainability of network structures in presence of random perturbations. The model outcomes show that the stability of compartmentalized networks built on uniform operators depends on perturbations on between-subnetwork coupling, while the stability of networks built on mutation operators depends on their assimilation capacity. Through the study of eigenvalues of the Laplacian, we succeed in measuring the degree of network robustness and resilience. Our results also permit to situate the Price theorem, both in its standard and expanded forms, in the context of network evolutionary variational identity.     

Resequencing core accessions of a pedigree identifies derivation of genomic segments and key agronomic trait loci during cotton improvement

Upland cotton (Gossypium hirsutum) is the world's largest source of natural fibre and dominates the global textile industry. Hybrid cotton varieties exhibit strong heterosis that confers high fibre yields, yet the genome‐wide effects of artificial selection that have influenced Upland cotton during its breeding history are poorly understood. Here, we resequenced Upland cotton genomes and constructed a variation map of an intact breeding pedigree comprising seven elite and 19 backbone parents. Compared to wild accessions, the 26 pedigree accessions underwent strong artificial selection during domestication that has resulted in reduced genetic diversity but stronger linkage disequilibrium and higher extents of selective sweeps. In contrast to the backbone parents, the elite parents have acquired significantly improved agronomic traits, with an especially pronounced increase in the lint percentage. Notably, identify by descent (IBD) tracking revealed that the elite parents inherited abundant beneficial trait segments and loci from the backbone parents and our combined analyses led to the identification of a core genomic segment which was inherited in the elite lines from the parents Zhong 7263 and Ejing 1 and that was strongly associated with lint percentage. Additionally, SNP correlation analysis of this core segment showed that a non‐synonymous SNP (A‐to‐G) site in a gene encoding the cell wall‐associated receptor‐like kinase 3 (GhWAKL3) protein was highly correlated with increased lint percentage. Our results substantially increase the valuable genomics resources available for future genetic and functional genomics studies of cotton and reveal insights that will facilitate yield increases in the molecular breeding of cotton.     

以Candin为佐剂的人乳头瘤病毒多肽 治疗疫苗诱导小鼠的体液免疫应答

目的研究以Candin为佐剂的人乳头瘤病毒(Human papillomavirus,HPV)多肽治疗疫苗诱导小鼠产生的体液免疫应答。方法分别采用PBS(对照)、佐剂Candin(150μL/只)、HPV16 E7多肽[3个E7多肽片段,50μg/(段·只)]和包含佐剂Candin与HPV16 E7多肽的疫苗对C57BL/6小鼠进行免疫接种实验,在第21天和第42天各加强1次免疫,剂量同第1次免疫。第3次免疫后2周,颈脱位处死小鼠,取血清。以ELISA法检测血清总IgG、IgG1和IgG2a抗体浓度。结果经多肽(P=0.001,P0.001)和疫苗(P=0.001,P=0.008)免疫的小鼠总IgG抗体、IgG1抗体水平均较对照组高,差异有统计学意义。与对照组相比,疫苗(P=0.008)可明显提高小鼠血清中IgG2a抗体水平。结论包含佐剂Candin及HPV16 E7多肽的疫苗能诱导小鼠产生明显的体液免疫应答。     

Effects of biodiversity,stand factors and functional identity on biomass and productivity during the restoration of subtropical forests in Central China

恢复梯度上华中亚热带森林生物多样性、林分因子及功能特性对生物量、生产力的影响 草地群落上进行的控制实验大都发现生物多样性对生态系统功能有显著促进作用。然而,在天然林中,多样性与林分因子、群落功能特性的相对作用大小仍存在争议。本文在森林恢复梯度上,研究这3类因素对生物量和生产力的相对影响。我们在湖北神农架设置了处于不同恢复阶段的24块(600 m²)亚热 带森林样地,计算了林分生物量和生产力。选择5个关键的植物功能性状,并计算了群落的功能多样性(功能丰富度、功能均匀度和功能离散度)和性状的加权平均值(CWM)。使用一般线性模型(GLMs)、变异分离等方法探究林分因子(密度、林龄、群落最大树高等)、功能特性、物种和功能多样性对生物量和生产力的相对重要性。研究结果表明,随着森林恢复,林分生物量和生产力显著增加,群落物种丰富度显著增加,而功能离散度显著降低。变异分离结果表明,多样性对生物量和生产力的单独效应不显著,但可能通过与林分因子和功能特性的协同效应来影响生物量和生产力。总体而言,我们发现林分因子对亚热带森林生物量和生产力的影响最大,功能特性显著影响生产力,但不影响生物量。这些结果说明,在森林经营中,调整林分结构和群落物种特性是提高森林碳储量和固碳潜力的有效途径。     

The appendage role of insect disco genes and possible implications on the evolution of the maggot larval form

Though initially identified as necessary for neural migration, Disconnected and its partially redundant paralog, Disco-related, are required for proper head segment identity during Drosophila embryogenesis. Here, we present evidence that these genes are also required for proper ventral appendage development during development of the adult fly, where they specify medial to distal appendage development. Cells lacking the disco genes cannot contribute to the medial and distal portions of ventral appendages. Further, ectopic disco transforms dorsal appendages toward ventral fates; in wing discs, the medial and distal leg development pathways are activated. Interestingly, this appendage role is conserved in the red flour beetle, Tribolium (where legs develop during embryogenesis), yet in the beetle we found no evidence for a head segmentation role. The lack of an embryonic head specification role in Tribolium could be interpreted as a loss of the head segmentation function in Tribolium or gain of this function during evolution of flies. However, we suggest an alternative explanation. We propose that the disco genes always function as appendage factors, but their appendage nature is masked during Drosophila embryogenesis due to the reduction of limb fields in the maggot style Drosophila larva.     

Direct interaction between Teashirt and Sex combs reduced proteins, via Tsh's acidic domain, is essential for specifying the identity of the prothorax in Drosophila

teashirt (tsh) encodes a zinc-finger protein that is thought to be part of a network that contributes to regionalization of the Drosophila embryo and establishes the domains of Hox protein function. tsh and the Hox gene Sex combs reduced (Scr) are essential to establish the identity of the first thoracic segment. We used the development of the first thoracic segment as a paradigm for Scr dependent regional morphological distinctions. In this specific context, we asked whether Tsh protein could have a direct influence on Scr activity. Here we present evidence that Tsh interacts directly with Scr and this interaction depends in part on the presence of a short domain located in the N-terminal half of Teashirt called "acidic domain". In vivo, expression of full length Tsh can rescue the tsh null phenotype throughout the trunk whereas Tsh lacking the Scr interacting domain rescues all the trunk defects except in the prothorax. We suggest this provides insights into the mechanism by which Tsh, in concert with Scr, specifies the prothoracic identity.     

Is it God Speaking? Agency of Deities in the Western Himalaya

ABSTRACT

In many ethnographies, deities reflect social structures, represent power relations, or serve as a resource for individuals. However, believers usually do not doubt the existence of deities and their agency: that is, their ability to act and initiate change. The gap between these points of view narrows in the religious experiences in the Indian Himalayas. There, the local population, who communicate with local deities via mediums, face an epistemological problem: how to be certain that they are, indeed, talking with their gods. Furthermore, the believers are aware that they play a role in the decisions of the gods. These two aspects of the religious experience are expressed in the gradual transition of the gods from a Pahā?ī to a pan-Hindu identity, an indication of the way in which the agency of the gods is being challenged and is subject to negotiation by the locals.     

Cell line cross-contamination: How aware are mammalian cell culturists of the problem and how to monitor it?

HeLa was the first human cell line established (1952) and became one of the most frequently used lines because of its hardiness and rapid growth rate. During the next two decades, the development of other human cell lines mushroomed. One reason for this became apparent during the 1970s, when it was demonstrated that many of these cell lines had been overgrown and replaced by fast-growing HeLa cells inadvertently introduced into the original cultures. Although the discovery of these "HeLa contaminants" prompted immediate alarm, how aware are cell culturists today of the threat of cell line cross-contamination? To answer this question, we performed a literature search and conducted a survey of 483 mammalian cell culturists to determine how many were using HeLa contaminants without being aware of their true identity and how many were not using available means to ensure correct identity. Survey respondents included scientists, staff, and graduate students in 48 countries. HeLa cells were used by 32% and HeLa contaminants by 9% of survey respondents. Most were also using other cell lines; yet, only about a third of respondents were testing their lines for cell identity. Of all the cell lines used, 35% had been obtained from another laboratory instead of from a repository, thus increasing the risk of false identity. Over 220 publications were found in the PubMed database (1969-2004) in which HeLa contaminants were used as a model for the tissue type of the original cell line. Overall, the results of this study indicate a lack of vigilance in cell acquisition and identity testing. Some researchers are still using HeLa contaminants without apparent awareness of their true identity. The consequences of cell line cross-contamination can be spurious scientific conclusions; its prevention can save time, resources, and scientific reputations.