Isolation and characterization of microsatellite markers from the limpet Cellana grata

This note describes the development of nine polymorphic microsatellite loci in the limpet Cellana grata to investigate population structure and cohort variation in this species. The number of alleles ranged from seven to 22 and observed heterozygosity ranged from 0.62 to 0.95. Deviation from the Hardy-Weinberg equilibrium was detected in two loci, both as a result of heterozygote deficiency. Null alleles were detected in one of these loci. These genetic markers will be used to investigate the genetic structure of C. grata populations, as well as variation among cohorts of this common intertidal species.     

Plant Biodiversity in China: Richly Varied, Endangered, and in Need of Conservation

China is among the world's richest countries in terms of plant biodiversity. Besides the abundant flora, containing some 33,000 vascular plants (30,000 angiosperms, 250 gymnosperms, and 2600 pteridophytes), there is extraordinary ecosystem diversity, as well as a large pool of both wild and cultivated germplasms. China is also considered one of the main centers of origin and diversification for seed plants on Earth, and is especially profuse in phylogenetically primitive taxa and/or paleoendemics due to the refuge role glaciation played during the Quaternary period. The collision with the Indian subcontinent significantly enriched Chinese flora and led to the formation of many neoendemisms. However, flora distribution remains uneven, and some local floristic hotspots are found across China, such as Yunnan, Sichuan and Taiwan. Unfortunately, this biodiversity faces enormous threats, which have increased substantially over the last 50 years. The combined effects of habitat destruction and/or fragmentation, environmental contamination, over-exploitation of natural resources, and to a lesser extent, introduction of exotic species, have caused irreparable damage to China's plant biodiversity. Burgeoning economic and population growth have also contributed to this deterioration. It is believed that up to 5000 flora species are currently endangered in China, with some taxa having already become extinct. Although in recent years government authorities have made some efforts to preserve biodiversity, much work remains to be done. While China has established an extensive network of nature reserves and protected areas, encompassing more than 16% of the total land area, insufficient budgetary and staffing commitments are common limitations in their management structures. Ex-situ conservation is also deficient, primarily because the botanical gardens are not representative of several local floras, nor are they often of adequate size or representative of endangered species. The lack of effective and efficient environmental legislation and education are also problems that continue to accelerate the loss of plant biodiversity in China.     

防洪改善计划对鸟类的生态影响

香港特别行政区新界内有23 hm^2的鱼塘和22 hm^2的耕地,在“元朗-锦田-牛潭尾主要防洪改善计划”中被改变成两条防洪渠（防洪渠60号和43号）.于该防洪改善计划中的生态监察调查中发现这两条防洪渠的鸟类数量均较原先的生境大大减少.在耕地改变成防洪渠43号的过程中,鸟类密度由33.9 只/hm^2减少至2.2只/hm^2.在鱼塘改变成防洪渠60号的过程中,鸟类密度由5.2 只/hm^2 减少至0.4只/hm^2.研究亦发现一些原本在鱼塘和耕地很常见的鸟类物种因为生境被改变而消失.这些转变可能和食物,植被及生境复杂程度的减少有关.另一方面,为纾缓因这防洪改善计划中损失的耕地生境,渠务署在防洪渠43号的河岸铺上混凝土草格,促进植物繁衍,为鸟类提供生境.但研究发现以混凝土草格建造的草坡并未能提供有效的纾缓措施,取代耕地生境以减少生态影响.     

GFS9/TT9 contributes to intracellular membrane trafficking and flavonoid accumulation in Arabidopsis thaliana

Flavonoids are the most important pigments for the coloration of flowers and seeds. In plant cells, flavonoids are synthesized by a multi‐enzyme complex located on the cytosolic surface of the endoplasmic reticulum, and they accumulate in vacuoles. Two non‐exclusive pathways have been proposed to mediate flavonoid transport to vacuoles: the membrane transporter‐mediated pathway and the vesicle trafficking‐mediated pathway. No molecules involved in the vesicle trafficking‐mediated pathway have been identified, however. Here, we show that a membrane trafficking factor, GFS9, has a role in flavonoid accumulation in the vacuole. We screened a library of Arabidopsis thaliana mutants with defects in vesicle trafficking, and isolated the gfs9 mutant with abnormal pale tan‐colored seeds caused by low flavonoid accumulation levels. gfs9 is allelic to the unidentified transparent testa mutant tt9. The responsible gene for these phenotypes encodes a previously uncharacterized protein containing a region that is conserved among eukaryotes. GFS9 is a peripheral membrane protein localized at the Golgi apparatus. GFS9 deficiency causes several membrane trafficking defects, including the mis‐sorting of vacuolar proteins, vacuole fragmentation, the aggregation of enlarged vesicles, and the proliferation of autophagosome‐like structures. These results suggest that GFS9 is required for vacuolar development through membrane fusion at vacuoles. Our findings introduce a concept that plants use GFS9‐mediated membrane trafficking machinery for delivery of not only proteins but also phytochemicals, such as flavonoids, to vacuoles.     

High‐Performance,Transparent, Dye‐Sensitized Solar Cells for See‐Through Photovoltaic Windows

Dye‐sensitized solar cells (DSCs) have attracted great interest as one of the most promising photovoltaic technologies, and transparent DSCs show potential applications as photovoltaic windows. However, the competition between light absorption for photocurrent generation and light transmittance for obtaining high transparency limits the performance of transparent DSCs. Here, transparent DSCs exhibiting a high light transmittance of 60.3% and high energy conversion efficiency (3.66%) are reported. The strategy is to create a cocktail system composed of ultraviolet and near‐infrared dye sensitizers that selectively and efficiently harvest light in the invisible or low‐eye‐sensitivity region while transmitting light in high‐eye‐sensitivity regions. This new design provides a reasonable approach for realizing high efficiency and transparency DSCs that have potential applications as photovoltaic windows.     

Comparative genomics of methicillin-resistant Staphylococcus aureus ST239: distinct geographical variants in Beijing and Hong Kong

Background

The ST239 lineage is a globally disseminated, multiply drug-resistant hospital-associated methicillin-resistant Staphylococcus aureus (HA-MRSA). We performed whole-genome sequencing of representative HA-MRSA isolates of the ST239 lineage from bacteremic patients in hospitals in Hong Kong (HK) and Beijing (BJ) and compared them with three published complete genomes of ST239, namely T0131, TW20 and JKD6008. Orthologous gene group (OGG) analyses of the Hong Kong and Beijing cluster strains were also undertaken.

Results

Homology analysis, based on highest-percentage nucleotide identity, indicated that HK isolates were closely related to TW20, whereas BJ isolates were more closely related to T0131 from Tianjin. Phylogenetic analysis, incorporating a total of 30 isolates from different continents, revealed that strains from HK clustered with TW20 into the ‘Asian clade’, whereas BJ isolates and T0131 clustered closely with strains of the ‘Turkish clade’ from Eastern Europe. HK isolates contained the typical φSPβ-like prophage with the SasX gene similar to TW20. In contrast, BJ isolates contained a unique 15 kb PT1028-like prophage but lacked φSPβ-like and φSA1 prophages. Besides distinct mobile genetic elements (MGE) in the two clusters, OGG analyses and whole-genome alignment of these clusters highlighted differences in genes located in the core genome, including the identification of single nucleotide deletions in several genes, resulting in frameshift mutations and the subsequent predicted truncation of encoded proteins involved in metabolism and antimicrobial resistance.

Conclusions

Comparative genomics, based on de novo assembly and deep sequencing of HK and BJ strains, revealed different origins of the ST239 lineage in northern and southern China and identified differences between the two clades at single nucleotide polymorphism (SNP), core gene and MGE levels. The results suggest that ST239 strains isolated in Hong Kong since the 1990s belong to the Asian clade, present mainly in southern Asia, whereas those that emerged in northern China were of a distinct origin, reflecting the complexity of dissemination and the dynamic evolution of this ST239 lineage.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2164-15-529) contains supplementary material, which is available to authorized users.     

香港桦木科一新种——香港鹅耳枥(英文)

报道了桦木科(Betulaceae)鹅耳枥属(Carpinus L.)一新种——香港鹅耳枥(C.insularis N.H.Xia,K.S.PangY.H.Tong)。香港鹅耳枥与太鲁阁鹅耳枥(C.hebestroma Yamamoto)及多脉鹅耳枥(C.polyneura Franch.)相似,但习性灌木状,叶具13~16对侧脉,先端锐尖,边缘锯齿的芒尖较短,果苞宽半卵形或半卵形,长8~14 mm,小坚果顶端密被长柔毛且疏具树脂状腺体,与后两者易于区别。     

FRIENDS OF WILDLIFE SOUND AT NSA

ABSTRACT

The problem of categorization arises in any classification system because classes should be discrete while the characteristics of most natural objects and aspects of nature are more or less gradual. In systematics, this problem usually is solved by creating several levels of categories, such as class, order, family, genus and species. In the existing killer whale discrete call classification, only two levels occur—call type and call subtype. In this paper we describe structural categories at a broader level than call type in the discrete sounds of killer whales and compare these categories between and within vocal clans in a community of resident killer whales from Southeast Kamchatka, Russian Far East, and also with killer whales outside this community. We found four main classes of discrete calls in the repertoire of resident killer whales from Southeast Kamchatka. The calls of Southeast Kamchatka transient killer whales and Sakhalin killer whales do not fall into these classes. This suggests that the resident killer whale community from Southeast Kamchatka has some rules defining the structure of calls which are typical for this community. Consequently, all resident killer whales from Southeast Kamchatka can be said to share the same vocal tradition.