The antennal sensilla of Melipona quadrifasciata (Hymenoptera: Apidae: Meliponini): a study of different sexes and castes

The sensilla of insects are integumental units that play a role as sensory structures and are crucial for the perception of stimuli and for communication. In this study, we compared the antennal sensilla of females (workers and queens), males (haploid (n) and diploid (2n)), and queen-like males (QLMs, resulting from 2n males after juvenile hormone (JH) treatment) in the stingless bee Melipona quadrifasciata. Images of the dorsal antenna surfaces were acquired using a scanning electron microscope. As reported for other hymenopterans, this species exhibits a heterogeneous sensillar distribution along the antennae. Thirteen different types of sensilla were found in the antennae of M. quadrifasciata: trichodea (subtypes I to VI), chaetica (subtypes I and II), placodea, basiconica, ampullacea, coeloconica, and coelocapitula. Sensilla trichodea I were the most abundant, followed by sensilla placodea, which might function in olfactory perception. Sensilla basiconica, sensilla chaetica I, sensilla coeloconica, and sensilla ampullacea were found exclusively in females. In terms of the composition and size of the sensilla, the antennae of QLMs most closely resemble those of the 2n male, although QLMs exhibit a queen phenotype. This study represents the first comparative analysis of the antennal sensilla of M. quadrifasciata. The differences found in the type and amount of sensilla between the castes and sexes are discussed based on the presumed sensillary functions.     

快餐:摒弃还是改良

快餐文化,作为一种文化的代名词,时下正方兴未艾,渗透人们日常生活的每个角落。但另一方面,也代表着文化中如稀薄、复制、炒作、膨化、堕落等等,使部分人非常排斥甚至痛恨。而快餐食品,作为引发“快餐文化”这个词语的由头,作为一种现代生活中食物的衍生物;其将是怎样的命运呢?     

Noroviruses: State of the Art

Noroviruses are a common cause of both endemic and epidemic gastroenteritis. These highly infectious viruses usually cause self-limited disease, but chronic infections occur in highly immunocompromised patients and unusual manifestations are also being described in some populations. Histoblood-group antigen expression is now recognized as an important susceptibility factor for many norovirus strains, but a correlate of acquired immunity to infection or illness has not yet been identified. Currently, treatment and prevention strategies rely on non-specific measures. However, virus-like particles containing capsid antigens are undergoing evaluation as a vaccine candidate for illness prevention. This article reviews the biologic properties, epidemiology, clinical features, host susceptibility, diagnosis, and treatment and prevention of norovirus infection.     

“地中海的心脏”瓦莱塔

<正>瓦莱塔是南欧岛国马耳他的首都,座落在马耳他岛东北部,是全国政治、文化和商业的中心,也是欧、亚、非海运交通的枢纽,战略地位十分重要,更是闻名世界的旅游城市,素有"地中海的心脏"、"海上花园"之称。瓦莱塔依山傍水,环境优雅,气候宜人,加上得天独厚的地理位置,这里安静恬适,听不到大城市的喧嚣,也没有大工业的烟尘,污染程度低,交通便利,市场繁荣,社会秩序良好,人与自然和谐相处。这里春天来得特别早,当欧洲还处在千里冰封的严冬季节时,瓦莱塔就已春暖     

Emerging Chemicals of Concern: Preface

<正>On June 29,2015,the Chemical Abstracts Service(CAS),the world’s authority for chemical information,registered the 100millionth chemical substance in the CAS REGISTRY,the world’s largest database of unique chemical substances(http://www.cas.org/news/media-releases/100-millionthsubstance).There are different estimates of the number of chemicals in commercial use.Depending on the source,that number could range from around 8,000(counting only those     

8:2氟调聚醇(8:2FTOH)厌氧生物降解特性

为了阐明厌氧环境下全氟羧酸（PFCAs）等全氟化合物的迁移归趋,研究了8：2氟调聚醇（8：2FTOH）的厌氧降解性能.结果表明,取自市政污水处理厂的污泥在厌氧条件下可还原降解8：2FTOH,并生成氟离子、全氟类和多氟类降解产物,且降解过程可采用双指数衰减模型拟合.在为期120d的培养中,8：2FTOH的摩尔降解率高达（93.2±0.9）%;摩尔回收率则随着培养时间的增加有下降的趋势,由培养初期（1d）的（97.5±5.1）%下降至末期（120d）的（68.9±4.0）%,这说明在培养后期可能产生了未知的降解产物或生成了未知的挥发性产物.8：2不饱和氟调聚酸（8：2FTUA）和全氟辛酸（PFOA）分别是摩尔产率最高的多氟类和全氟类降解产物,分别介于（6.94±0.10）%~（24.2±1.5）%和（2.67±0.22）%~（14.9±1.0）%的范围内.多氟类降解产物的摩尔产率随培养时间的增加先增加后降低,而全氟类降解产物的摩尔产率则随培养时间的增加持续增加,这说明其可能分别为中间降解产物和最终降解产物.     

A review of myrmecophily in ant nest beetles (Coleoptera: Carabidae: Paussinae): linking early observations with recent findings

Myrmecophily provides various examples of how social structures can be overcome to exploit vast and well-protected resources. Ant nest beetles (Paussinae) are particularly well suited for ecological and evolutionary considerations in the context of association with ants because life habits within the subfamily range from free-living and predatory in basal taxa to obligatory myrmecophily in derived Paussini. Adult Paussini are accepted in the ant society, although parasitising the colony by preying on ant brood. Host species mainly belong to the ant families Myrmicinae and Formicinae, but at least several paussine genera are not host-specific. Morphological adaptations, such as special glands and associated tufts of hair (trichomes), characterise Paussini as typical myrmecophiles and lead to two different strategical types of body shape: while certain Paussini rely on the protective type with less exposed extremities, other genera access ant colonies using glandular secretions and trichomes (symphile type). We compare these adaptations with other taxonomic groups of insects by joining contemporary research and early sources and discuss the possibility of an attracting or appeasing effect of the secretion. Species that are ignored by their host ants might use chemical mimicry instead. Furthermore, vibrational signals may contribute to ant–beetle communication, and chemical signals have proven to play a role in host finding. The powerful defense chemistry of paussines as “bombardier beetles” is not used in contact with host ants. We attempt to trace the evolution of myrmecophily in paussines by reviewing important aspects of the association between paussine beetles and ants, i.e. morphological and potential chemical adaptations, life cycle, host specificity, alimentation, parasitism and sound production.

Cypress terpenes in sawfly larva of Susana cupressi (Hymenoptera: Symphyta: Tenthredinoidea)

The Science of Nature -     

Squeezing light out of crystals: Triboluminescence

Triboluminescence is the light emitted when mechanical energy is applied to a crystal. Many common substances such as sugar and copper sulfate are triboluminescent. The origin of the light and the mechanical, chemical, and crystallographic requirements of the phenomenon are described in this paper.     

生命之源H_2O

水(H_2O)由两个氢原子和一个氧原子组成,它是自然界中最简单、最常见的化合物,也是我们赖以生存的地球上覆盖最广、数量最多的自然物质。地球上的水确实丰富,总体积约为13.8亿立方公里。但十分可惜的是,这些水98%是咸水,主要分布在海洋中。淡水只占地球水总量的2%,约有3000万立方公里,而这2%     

民主：环境保护的政治基础

通过对全球100多个国家的环境指数比较研究发现,环境保护与民主水平之间的相关性存在统计学的显著性。民主水平无一例外地和5个不同环境评价指标之间的相关性具有明显的统计学显著性。这表明,民主水平的提高有助于促进环境治理、环境可持续发展,有利于降低人们对环境的破坏。为此,解决环境问题需要进行相应的政治体制改革,为环境可持续发展扫除政治方面的障碍。     

聚乙烯微塑料的微生物降解研究进展

现代工业的发展使得塑料制品的使用量急剧增加,由此产生的大量废旧塑料垃圾在环境中裂解形成粒径更小的微塑料（<5 mm）.由于微塑料结构稳定,分布广泛且生物可利用性低,在环境中长期存在,已经逐渐成为对海洋生态和环境造成巨大影响的重要污染物.近年的研究表明,自然环境中存在一些能降解这些难降解微塑料的微生物,微生物降解无二次污染且对环境扰动少,在微塑料的去除中具有很好地应用潜力,但亦有一些局限性.综述了环境中数量最多的聚乙烯微塑料的微生物降解研究现状,着重探讨了降解效果和量化方法.基于微塑料生物分解效率普遍较低的现状,开展进一步的研究还非常有必要.     

欧盟绿皮书：PVC的环境问题（下）

4 PVC的废物管理欧盟委员会对PVC废物管理已在欧洲废物管理政策范围内进行，主要是对四种优选技术，即机械回收、化学回收、焚烧和填埋，进行了评估。委员会关于对废物管理的一般性战略评估证明了“体系原则”──即最优先预防废物的产生，其次是回收，最后是废物的安全处置。进而，在对环境无害的前提下，能量回收中的材料回收应该优先。这个原则是出于材料回收比能量回收具有更大的现实主义。当然还要考虑到环境、经济和科学等方面的影响。在某些情况下，对这些影响的评估倾向于能量回收优先。在1997年2月24日的决议中，委员会已经签署…     

Biosemiotics: a new understanding of life

Biosemiotics is the idea that life is based on semiosis, i.e., on signs and codes. This idea has been strongly suggested by the discovery of the genetic code, but so far it has made little impact in the scientific world and is largely regarded as a philosophy rather than a science. The main reason for this is that modern biology assumes that signs and meanings do not exist at the molecular level, and that the genetic code was not followed by any other organic code for almost four billion years, which implies that it was an utterly isolated exception in the history of life. These ideas have effectively ruled out the existence of semiosis in the organic world, and yet there are experimental facts against all of them. If we look at the evidence of life without the preconditions of the present paradigm, we discover that semiosis is there, in every single cell, and that it has been there since the very beginning. This is what biosemiotics is really about. It is not a philosophy. It is a new scientific paradigm that is rigorously based on experimental facts. Biosemiotics claims that the genetic code (1) is a real code and (2) has been the first of a long series of organic codes that have shaped the history of life on our planet. The reality of the genetic code and the existence of other organic codes imply that life is based on two fundamental processes--copying and coding--and this in turn implies that evolution took place by two distinct mechanisms, i.e., by natural selection (based on copying) and by natural conventions (based on coding). It also implies that the copying of genes works on individual molecules, whereas the coding of proteins operates on collections of molecules, which means that different mechanisms of evolution exist at different levels of organization. This review intends to underline the scientific nature of biosemiotics, and to this purpose, it aims to prove (1) that the cell is a real semiotic system, (2) that the genetic code is a real code, (3) that evolution took place by natural selection and by natural conventions, and (4) that it was natural conventions, i.e., organic codes, that gave origin to the great novelties of macroevolution. Biological semiosis, in other words, is a scientific reality because the codes of life are experimental realities. The time has come, therefore, to acknowledge this fact of life, even if that means abandoning the present theoretical framework in favor of a more general one where biology and semiotics finally come together and become biosemiotics.     

历史现象学:马克思和胡塞尔

马克思和胡塞尔均对内历史或历史的内在本质和历史认识论做出了经典的分析。关于前者,胡塞尔认为它根源于主体的意向性,马克思则坚持它根源于物质生活资料及生产方式这一客体。关于后者,胡塞尔阐述了"纵向本质直观"这一方法及其理论依据,马克思则论证了"透过现象看本质"方法的合理性。总起来看,马克思对这两个问题的解答在逻辑上更为自洽,也更加契合史学实践。