Global estimate of aerosol direct radiative forcing from satellite measurements

Atmospheric aerosols cause scattering and absorption of incoming solar radiation. Additional anthropogenic aerosols released into the atmosphere thus exert a direct radiative forcing on the climate system. The degree of present-day aerosol forcing is estimated from global models that incorporate a representation of the aerosol cycles. Although the models are compared and validated against observations, these estimates remain uncertain. Previous satellite measurements of the direct effect of aerosols contained limited information about aerosol type, and were confined to oceans only. Here we use state-of-the-art satellite-based measurements of aerosols and surface wind speed to estimate the clear-sky direct radiative forcing for 2002, incorporating measurements over land and ocean. We use a Monte Carlo approach to account for uncertainties in aerosol measurements and in the algorithm used. Probability density functions obtained for the direct radiative forcing at the top of the atmosphere give a clear-sky, global, annual average of -1.9 W m(-2) with standard deviation, +/- 0.3 W m(-2). These results suggest that present-day direct radiative forcing is stronger than present model estimates, implying future atmospheric warming greater than is presently predicted, as aerosol emissions continue to decline.     

Dietary sterols: Role in larval feeding behaviour of the Southwestern Corn Borer,Diatraea grandiosella

Zusammenfassung Eine Beziehung zwischen chemischer Struktur und biologischer Aktivität wurde im Einfluss diätetischer Sterole auf das Fütterungsverhalten frisch geschlüpfter Larven vonDiatraea grandiosella gefunden. Die experimentellen Resultate zeigen, dass die C₂₉-Pflanzensterole, -Sitosterol und Stigmasterol, die Futteraufnahme anregen, Cholesterol, 7-Dehydrocholesterol, Ergosterol und -Sitosterolazetat sich in dieser Hinsicht neutral verhalten und Cholesterol-Ester die Futteraufnahme hemmen.     

Effect of diet on response to juvenile hormone inGalleria mellonella larvae

Zusammenfassung Mit Juvenilhormon und JH-Derivaten injizerte Larven der WachsmotteGalleria mellonella zeigten stärkere morphogenetische Effekte, wenn ihre Nahrung Bienenwachs entheilt, als wenn diese fehlt.     

Selectivity of CC Traps in Catching Green Leafhoppers and Thrips

在中国广西南宁,测定８种不同基座颜色的ＣＣ诱捕器对豇豆（ＶｉｇｎａｓｅｓｑｕｉｐｅｄａｌｉｓＷｒｉｇｈｔ）上的叶蝉、蓟马的诱捕作用。蓝色基座诱捕器对华筒管蓟马（ＨａｐｌｏｔｈｒｉｐｓｃｈｉｎｅｎｓｉｓＰｒｉｅｓｎｅｓ）的诱集量为白色基座诱捕器的２倍（２２．８头／诱捕器天）,其他基座颜色诱捕器的诱捕量为０．１～１．７头／诱捕器天。ＣＣ诱捕器对叶蝉（Ｅｍｐｏａｓｃａｓｐｐ．）的诱集量为４头／诱捕器天,不同基座颜色诱捕器的诱集量差异不显著。在印度,测定白色、黄色和绿色基座诱捕器对花生上两种蓟马的诱捕作用。白色基座诱捕器对茶黄蓟马（ＳｃｉｒｔｏｔｈｒｉｐｓｄｏｒｓａｌｉｓＨｏｏｄ）的诱集量为３９．８头／诱捕器天,为黄色基座诱捕器的２倍多。绿色基座诱捕器的诱集量最少。白色基座诱捕器对瓜蓟马（ＴｈｒｉｐｓｐａｌｍｉＫａｒｎｙ）的诱捕量（１７．３头／诱捕器天）也显著高于黄色基座诱捕器（１１．０头／诱捕器天）。结论为：白色和蓝色基座诱捕器可用于监测豇豆、花生上蓟马的种群数量。     

Magnetic and flotation studies of banded hematite quartzite (BHQ) ore for the production of pellet grade concentrate

To identify and establish beneficiation techniques for banded hematite quartzite (BHQ) iron ore, a comprehensive research on BHQ ore treatment was carried out. The BHQ ore was assayed as 38.9wt% Fe, 42.5wt% SiO₂, and 1.0wt% Al₂O₃. In this ore, hematite and quartz are present as the major mineral phases where goethite, martite, and magnetite are present in small amounts. The liberation of hematite particles can be enhanced to about 82% by reducing the particle size to below 63 μm. The rejection of silica particles can be obtained by magnetic and flotation separation techniques. Overall, the BHQ ore can be enriched to 65.3wt% Fe at 61.9% iron recovery. A flowsheet has been suggested for the commercial exploitation of the BHQ ore.     

热处理作用下碳钢氢腐蚀裂纹愈合规律

对含氢腐蚀裂纹的碳钢进行再热处理后,SEM观察表明,氢蚀裂发生了不同程度的愈合,实验结果表明：长度约为10μm的碳钢氢蚀裂纹完全愈合的热处理条件下是从室温到1000℃热循环5次,共10h,氢蚀裂纹的愈合机制是热扩散,发生氢蚀裂纹愈合的动力是氢蚀气泡或裂纹长大导致的塑性变 能E8。在铁、碳和氢原子扩散都足够快的情况下,氢蚀裂纹愈合的条件是E8大于裂纹愈合所必须克服的表面张力能。     

Wnt-beta-catenin signaling initiates taste papilla development

Fungiform taste papillae form a regular array on the dorsal tongue. Taste buds arise from papilla epithelium and, unusually for epithelial derivatives, synapse with neurons, release neurotransmitters and generate receptor and action potentials. Despite the importance of taste as one of our five senses, genetic analyses of taste papilla and bud development are lacking. We demonstrate that Wnt-beta-catenin signaling is activated in developing fungiform placodes and taste bud cells. A dominant stabilizing mutation of epithelial beta-catenin causes massive overproduction of enlarged fungiform papillae and taste buds. Likewise, genetic deletion of epithelial beta-catenin or inhibition of Wnt-beta-catenin signaling by ectopic dickkopf1 (Dkk1) blocks initiation of fungiform papilla morphogenesis. Ectopic papillae are innervated in the stabilizing beta-catenin mutant, whereas ectopic Dkk1 causes absence of lingual epithelial innervation. Thus, Wnt-beta-catenin signaling is critical for fungiform papilla and taste bud development. Altered regulation of this pathway may underlie evolutionary changes in taste papilla patterning.     

LAYERED ARCHITECTURE FOR ASSEMBLING BUSINESS APPLICATIONS FROM DISTRIBUTED COMPONENTS

Modern business applications are generally characterized as: distributed across many processors and/or sites, access data from multiple sources and have web-based interfaces. These applications may also involve systems or processes from multiple companies or vendor provided services. The changing business environment and technologies requires that the application be agile and adoptable in short period. Component based development has recently attracted increased attention as a preferred technology for developing business applications. However, the tools and techniques for the design, implementation, management and deployment of applications based on these technologies are at a very early stage of development. This paper presents an overview of a distributed architecture for the deployment of applications based on business components. The application of the architecture in an auto insurance claim domain is briefly described. A number of open research issues have been identified.     

PD-1 expression on HIV-specific T cells is associated with T-cell exhaustion and disease progression

Functional impairment of T cells is characteristic of many chronic mouse and human viral infections. The inhibitory receptor programmed death 1 (PD-1; also known as PDCD1), a negative regulator of activated T cells, is markedly upregulated on the surface of exhausted virus-specific CD8 T cells in mice. Blockade of this pathway using antibodies against the PD ligand 1 (PD-L1, also known as CD274) restores CD8 T-cell function and reduces viral load. To investigate the role of PD-1 in a chronic human viral infection, we examined PD-1 expression on human immunodeficiency virus (HIV)-specific CD8 T cells in 71 clade-C-infected people who were naive to anti-HIV treatments, using ten major histocompatibility complex (MHC) class I tetramers specific for frequently targeted epitopes. Here we report that PD-1 is significantly upregulated on these cells, and expression correlates with impaired HIV-specific CD8 T-cell function as well as predictors of disease progression: positively with plasma viral load and inversely with CD4 T-cell count. PD-1 expression on CD4 T cells likewise showed a positive correlation with viral load and an inverse correlation with CD4 T-cell count, and blockade of the pathway augmented HIV-specific CD4 and CD8 T-cell function. These data indicate that the immunoregulatory PD-1/PD-L1 pathway is operative during a persistent viral infection in humans, and define a reversible defect in HIV-specific T-cell function. Moreover, this pathway of reversible T-cell impairment provides a potential target for enhancing the function of exhausted T cells in chronic HIV infection.