NEAR's flyby of 253 mathilde: images of a C asteroid

On 27 June 1997, the Near Earth Asteroid Rendezvous (NEAR) spacecraft flew within 1212 kilometers of asteroid 253 Mathilde. Mathilde is an irregular, heavily cratered body measuring 66 kilometers by 48 kilometers by 46 kilometers. The asteroid's surface is dark (estimated albedo between 0.035 and 0.050) and similar in color to some CM carbonaceous chondrites. No albedo or color variations were detected. The volume derived from the images and the mass from Doppler tracking of the spacecraft yield a mean density of 1.3 +/- 0.2 grams per cubic centimeter, about half that of CM chondrites, indicating a porous interior structure.     

野生龙葵果中营养成分的研究

本研究对野生龙葵果营养成分进行了比较全面地分析测试，对矿物质及维生素含量进行分析的基础上，对野生龙葵果的其它营养成分进行了分析，并与一些常用果蔬进行了对比研究。结果表明，野生龙葵果含有丰富的营养成分。     

云南农业大学信息服务与用户调查研究分析

 通过对云南农业大学的教师、研究生和本科生的信息需求调查,了解到各类用户利用文献信息的状况和对文献信息的需求,为图书馆开展信息服务提供了依据。     

Immunoglobulin structure: amino terminal sequences of mouse myeloma proteins that bind phosphorylcholine

The amino terminal sequences of five light and heavy immunoglobulin chains from myeloma proteins of the BALB/c mouse with binding activity to phosphorylcholine are presented. Except for a single substitution in position 4, all five heavy chains have identical amino terminal sequences through the first hypervariable region. Proteins which share unique (idiotypic) antigenic determinants are identical through the first hypervariable region of their light and heavy chains. Proteins with differing idiotypic determinants have light chains of differing amino acid sequence. These observations suggest that the heavy chain plays a more important role than the light chain in determining the phosphorylcholine binding site.     

Noncanonical TGFβ signaling contributes to aortic aneurysm progression in Marfan syndrome mice

Transforming growth factor-β (TGFβ) signaling drives aneurysm progression in multiple disorders, including Marfan syndrome (MFS), and therapies that inhibit this signaling cascade are in clinical trials. TGFβ can stimulate multiple intracellular signaling pathways, but it is unclear which of these pathways drives aortic disease and, when inhibited, which result in disease amelioration. Here we show that extracellular signal-regulated kinase (ERK) 1 and 2 and Smad2 are activated in a mouse model of MFS, and both are inhibited by therapies directed against TGFβ. Whereas selective inhibition of ERK1/2 activation ameliorated aortic growth, Smad4 deficiency exacerbated aortic disease and caused premature death in MFS mice. Smad4-deficient MFS mice uniquely showed activation of Jun N-terminal kinase-1 (JNK1), and a JNK antagonist ameliorated aortic growth in MFS mice that lacked or retained full Smad4 expression. Thus, noncanonical (Smad-independent) TGFβ signaling is a prominent driver of aortic disease in MFS mice, and inhibition of the ERK1/2 or JNK1 pathways is a potential therapeutic strategy for the disease.     

烤烟新品种南江3号在贵州烟区的生态适应性研究

以K326为对照,研究了烤烟新品种南江3号在贵州五大具有生态代表性烟区的农艺性状、生育期性状、抗病特征、经济性状、外观质量及吸食品质等指标。结果表明:与K326相比,南江3号在贵州烟区长势强、生育期长、抗病力强、产量和产值高、烟叶外观质量好,吸食品质与K326相当,在贵州烟区具有很好的生态适应性。     

Bird habitat preferences drive hemoparasite infection in the Neotropical region

The role that the environment plays in vector-borne parasite infection is one of the central factors for understanding disease dynamics. We assessed how Neotropical bird foraging strata and habitat preferences determine infection by parasites of the genera Haemoproteus, Plasmodium, Leucocytozoon, and Trypanosoma and filarioids, and tested for phylogenetic signal in these host–parasite associations. We performed extensive searches of the scientific literature and created a database of hemoparasite surveys. We collected data on host body mass, foraging strata, habitat preference, and migratory status, and tested if host ecological traits predict each hemoparasite occurrence and prevalence using a phylogenetic Bayesian framework. Species of Plasmodium tend to infect birds from tropical forests while birds from altitudinal environments are likely to be infected by species of Leucocytozoon. The probability of a bird being infected by filarioid or Trypanosoma is higher in lowland forests. Bird species that occur in anthropic environments and dry habitats of tropical latitudes are more susceptible to infection by species of Haemoproteus. Host foraging strata is also influential and bird species that forage in the mid-high and canopy strata are more prone to infection by species of Haemoproteus and filarioids. We also identified phylogenetic signal for host–parasite associations with the probability of infection of Neotropical birds by any hemoparasite being more similar among more closely related species. We provided a useful framework to identify environments that correlate with hemoparasite infection, which is also helpful for detecting areas with potential suitability for hemoparasite infection due to land conversion and climate change.     

低磷胁迫对小麦镉吸收的影响

为探究低磷胁迫下小麦根系生理和形态的变化及其对镉的吸收能力的影响,以Ca₃（PO₄）₂作为磷源,通过砂培试验研究了在低磷胁迫下小麦根系形态和分泌物变化特征,以及这些变化对难溶态镉（CdCO₃）的活化与吸收的影响。结果表明,在低磷处理中,小麦地下部生物量显著低于对照,降幅为27.3%（P<0.05）,根长度、根表面积和根体积均显著变小（P<0.05）。此外,低磷胁迫下小麦地上部和地下部磷含量均显著降低,降幅分别为35.4%和23.1%（P<0.05）,但是显著促进了难溶态磷的溶解（P<0.05）。同时还发现低磷胁迫显著提高了小麦植株Cd含量和Cd的总活化量,增幅分别为190.8%和82.8%（P<0.05）。低磷胁迫下培养基pH降低了0.3,同时根中草酸根和苹果酸根含量显著升高,增幅分别为1 588.1%和37.7%（P<0.05）,由此可见,低磷胁迫下小麦通过分泌质子和羧酸根促进了磷的活化,并促进了Cd的活化,进而导致小麦Cd吸收的增加。这些结果阐明了低磷胁迫影响小麦Cd吸收的机制。     

Locally invasive lymphangiosarcoma in a young domestic shorthair

A 2-year-old, female spayed, domestic shorthair cat presented to the University of Missouri-Veterinary Medical Teaching Hospital (UMC-VMTH) with an approximately 11-month history of fluid-draining pockets along her ventral thorax and axillae. The skin in these regions was erythematous, and multiple areas drained a serous to serosanguinous fluid. Fluid-filled, nodules formed along the ventrum, but these nodules disappeared as fluid drained spontaneously. Histologic assessment of skin biopsies revealed areas of vascular proliferation extending along the deep margin of the section and rare instances of invasion into the superficial dermis. These vascular channels were devoid of cells, lined by variably pleomorphic endothelial cells which had a low mitotic index. Based on the mild to moderate pleomorphism, positive staining with prospero-related homeobox gene-1 (PROX-1), and the locally aggressive nature of the tumor, a final diagnosis of lymphangiosarcoma was made.