The above-ground coarse wood productivity of 104 Neotropical forest plots

The net primary production of tropical forests and its partitioning between long‐lived carbon pools (wood) and shorter‐lived pools (leaves, fine roots) are of considerable importance in the global carbon cycle. However, these terms have only been studied at a handful of field sites, and with no consistent calculation methodology. Here we calculate above‐ground coarse wood carbon productivity for 104 forest plots in lowland New World humid tropical forests, using a consistent calculation methodology that incorporates corrections for spatial variations in tree‐size distributions and wood density, and for census interval length. Mean wood density is found to be lower in more productive forests. We estimate that above‐ground coarse wood productivity varies by more than a factor of three (between 1.5 and 5.5 Mg C ha^?1 a^?1) across the Neotropical plots, with a mean value of 3.1 Mg C ha^?1 a^?1. There appear to be no obvious relationships between wood productivity and rainfall, dry season length or sunshine, but there is some hint of increased productivity at lower temperatures. There is, however, also strong evidence for a positive relationship between wood productivity and soil fertility. Fertile soils tend to become more common towards the Andes and at slightly higher than average elevations, so the apparent temperature/productivity relationship is probably not a direct one. Coarse wood productivity accounts for only a fraction of overall tropical forest net primary productivity, but the available data indicate that it is approximately proportional to total above‐ground productivity. We speculate that the large variation in wood productivity is unlikely to directly imply an equivalent variation in gross primary production. Instead a shifting balance in carbon allocation between respiration, wood carbon and fine root production seems the more likely explanation.     

枯草芽孢杆菌菌剂对人参黑斑病的生物防治效果

为明确枯草芽孢杆菌可湿性粉剂(WP)对人参黑斑病的防治效果及对人参生长的安全性,采用生长速率法测定枯草芽孢杆菌对人参黑斑病菌的室内抑菌效果,采用田间小区试验评价枯草芽孢杆菌对人参黑斑病的防治效果及其对人参的安全性.室内抑菌试验结果表明:枯草芽孢杆菌对人参黑斑病菌的菌丝生长具有较好的抑制作用,EC50和EC90分别为0....     

Fine‐scale population structure of Collichtys lucidus populations inferred from microsatellite markers

The spinyhead croaker Collichthys lucidus (Richardson) is a small sciaenid species distributed along the inshore waters of northwestern Pacific Ocean, and now has been listed as Key Protected Commercial Sources of Aquatic Animals and Plants in China. To delineate stock boundaries and inform conservation policy for its management, samples were collected from eight locations across the Chinese coastal waters and analyzed at nine microsatellite loci. C. lucidus populations showed low genetic diversity (expected heterozygosity = 0.445–0.542; observed heterozygosity = 0.392–0.539; Polymorphism Information Content = 0.268–0.684). Strong genetic fdifferentiation (F_st = 0.065–0.510, all significant after Bonferroni correction) among all populations and high levels of self‐recruitment (89.2%–91.5%) were observed, which suggested limited genetic exchange for this species. Clustering results of discriminant analysis of principal components and STRUCTURE found strong support for obvious genetic clusters (populations FZ, XM and SZ vs. populations SH, YRE, ZS, WZ and ND). The results of the present study not only supported the phylogeographic pattern of north‐south differentiation, but also suggested that C. lucidus populations may be predominantly sustained by self‐replenishment rather than by recruitment from distant populations.     

Evaluation of a granular formulation containing Metarhizium brunneum F52 (Hypocreales: Clavicipitaceae) microsclerotia in controlling eggs of Aedes aegypti (Diptera: Culicidae)

We evaluated the potential of a granular formulation of Metarhizium brunneum F52 containing microsclerotia (MbMSc granules) for control of Aedes aegypti by targeting eggs. MbMSc granules produced infective conidia within 14 days after application to 2.5?g moist potting soil, producing 5.9?×?10⁵, 2.08?×?10⁶ and 6.85?×?10⁶ conidia from 1, 5 and 25?mg MbMSc granules, respectively. Application of MbMSc triggered premature eclosion of eggs (EC_50?=?12?mg) with percentages as high as 31?±?2.9% and 67?±?4.3% of the eggs treated with 5 and 25?mg MbMSc granules, respectively, after 14 days on moist filter paper. Premature eclosion of eggs started at 3 days subsequent to MbMSc granule application and survival of larvae was significantly reduced for granule treated eggs (74?±?2.2%, 39?±?2.0% and 23?±?4.9% larvae survived for 1, 5 and 25?mg granule treatments, respectively, EC₅₀?=?4.9?mg). When MbMSc granules were applied in moist potting soil with mosquito eggs, rates of 1, 5 and 25?mg of MbMSc granules significantly reduced adult emergence with only 81?±?2.1%, 47?±?1.9%, and 34?±?2.1% emergence, respectively (EC₅₀?=?7?mg). Eggs treated with increasing concentrations of fungal conidia enhanced premature eclosion of eggs with an EC₅₀?=?1.6?×?10⁶ conidia/mL. Our results demonstrate that MbMSc granules are a promising candidate for control of A. aegypti and that fermentative production of Mb F52 microsclerotia as the active propagule has the potential for use for mosquito control.     

Simultaneous binding of Guidance Cues NET1 and RGM blocks extracellular NEO1 signaling

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城市化进程中城市热岛景观格局演变的时空特征——以厦门市为例

热岛效应作为城市化过程中产生的特有环境问题,对其形成和演变规律的研究有助于人们提出有效的应对措施。以厦门市为研究对象,利用1987—2007年等时间间隔、同时相的5景Landsat TM/ETM+遥感影像数据进行地表温度反演,在此基础上使用景观格局指数分析厦门城市热岛景观格局随城市化进程演变的趋势。结果表明:随着厦门城市化进程加深,整个热岛景观在逐渐变得更加破碎化,高等级热岛景观斑块个数、类型面积和个体面积都增大;新的高等级热岛景观斑块都出现在原有高等级斑块附近,致使高等级类型的邻近度增加而各类型之间相互接触的程度也增加;景观总体的聚合度逐渐下降,而高等级热岛景观类型的聚合度则呈上升趋势;景观水平的蔓延度总体呈下降趋势,优势度高的低等级热岛景观所占的比重下降,优势度逐渐降低;多样性指数、均匀度指数总体呈上升趋势,各热岛景观面积在各类型间的分配逐渐趋于均匀;热岛景观斑块的转化方面,在20 a间低等级斑块类型(1、2、3级)向高等级斑块类型(4、5、6级)转化的面积总体上呈增加趋势,而高等级斑块类型向低等级斑块类型转化的面积总体上呈减小趋势,且等级升高的面积明显大于同期等级降低的面积;就高等级热岛景观斑块而言,他们与3级热岛景观斑块间的相互转化最容易发生,远比高等级斑块内部各类型之间的相互转化来得容易,尤其6类和5类的转化是最为困难的热岛景观变化之一;从空间上看,各高等级热岛景观斑块都经历了数量增加、面积扩大、等级升高三个方面的变化,形成了海沧、新阳、杏林、厦门岛西北港口区和机场5个高温组团。利用景观指数分析城市热环境,可探明热岛景观随城市化演变的趋势,并为有效的热岛效应减缓措施提供直接的理论依据。     

ESCRT proteins and cell signalling

Subunits of the endosomal sorting complex required for transport (ESCRT) were identified as components of a molecular machinery that sorts ubiquitinated membrane proteins into the intraluminal vesicles (ILVs) of multivesicular endosomes (MVEs) for subsequent delivery to the lumen of lysosomes or related organelles. As many of the membrane proteins that undergo ESCRT-mediated sorting are signalling receptors that are ubiquitinated in response to ligand binding, ESCRT subunits have been hypothesized to play a crucial role in attenuation of cell signalling by mediating ligand-induced receptor degradation. Here we discuss this concept based on the examples from loss-of-function studies in model organisms and cell lines. The emerging picture is that ESCRTs are indeed involved in downregulation of receptor signalling pathways associated with cell survival, proliferation and polarity. In addition, the recent discovery of a positive role for the ESCRT pathway in Wnt signalling through sequestration of an inhibitory cytosolic component into MVEs illustrates that ESCRTs may also control signalling in ways that are independent of degradative receptor sorting.     

Development and characterization of wheat-Psathyrostachys huashanica partial amphiploids for resistance to stripe rust

Two partial amphiploid lines, B113 (32 plants) and B21 (13 plants), derived from a wheat-Psathyrostachys huashanica intergeneric cross were characterized by Giemsa C-banding and SDS-PAGE and evaluated for stripe rust resistance. All 15 partial amphiploid plants were aneuploids with either 50 (8 plants), 51 (6 plants) or 54 (1 plant) chromosomes. Some showed regular meiosis and all the P. huashanica chromosomes were included, although not in a single plant. Of 45 plants 34 showed specific bands on SDS-PAGE representing high molecular weight glutenin subunit (HMW-GS) and 41 had bands representing P. huashanica low molecular weight glutenin subunit (LMW-GS), including two new subunits. All 45 plants were highly resistant (10) or immune (35) to stripe rust mixed races CYR-30, CYR-31, Shuiyuan 7 and Shuiyuan 14. These amphiploid plants could be useful germplasm for enhancing stripe rust resistance and might improve wheat grain quality.     

Multivariate meta-analysis of proteomics data from human prostate and colon tumours

Background  

There is a vast need to find clinically applicable protein biomarkers as support in cancer diagnosis and tumour classification. In proteomics research, a number of methods can be used to obtain systemic information on protein and pathway level on cells and tissues. One fundamental tool in analysing protein expression has been two-dimensional gel electrophoresis (2DE). Several cancer 2DE studies have reported partially redundant lists of differently expressed proteins. To be able to further extract valuable information from existing 2DE data, the power of a multivariate meta-analysis will be evaluated in this work.