Experimental infection of chimpanzees with hepatitis C virus of genotype 5a: genetic analysis of the virus and generation of a standardized challenge pool

Six major genotypes (genotypes 1-6) of hepatitis C virus (HCV) have been identified. These genetic variants are being transmitted to chimpanzees, the only recognized animal model for the study of HCV. Genotype 5a (strain SA13), a variant found primarily in South Africa, has been transmitted to chimpanzees for the first time. Experimental infection of 2 chimpanzees was characterized by early appearance of viremia and peak virus titers of 10(5)-10(6) genome equivalents/mL. The HCV infection was resolved by week 15 after inoculation in 1 chimpanzee and persisted in the other. Both chimpanzees became anti-HCV-positive by week 14 after inoculation. Both chimpanzees developed viral hepatitis. The infectivity titer of a genotype 5a challenge pool prepared from the first passage of HCV in a chimpanzee was approximately 10(4) infectious doses/mL. Finally, sequence analysis of strain SA13 confirmed that genotype 5a is genetically distinct from other genotypes of HCV.     

A comparison of placebo response with major depressive disorder in patients recruited through newspaper advertising versus consultation referrals

Recent evidence indicates few differences between patients recruited through advertising and by consultation referral, and there is some suggestion that those recruited through advertising are more representative of the target community population. However little has been reported on differences in placebo response and compliance in these two patient groups. We conducted a retrospective chart review of 49 patients with major depressive disorder (MDD), recruited through advertising or consultation, randomized to placebo in five clinical trials. Variables included demographics, clinical history, efficacy, compliance, and completion data. Homogeneity was demonstrated for most variables. Differences in placebo groups included significantly lower Hamilton Rating Scale for Depression (HAM-D) scores for the advertisement group throughout the trials. Advertisement patients were also more likely to be early placebo responders and in remission at Days 14 and 28. No differences were found in completion rates or reasons for early termination. Compliance was excellent for both groups. Early placebo response of the advertisement group reinforces the need for trials of at least 8 weeks. In addition, consultation patients may have a more severe illness and be treatment resistant, suggesting they are less generalizable to community practice populations.     

Pigeon basal ganglia: insights into the neuroanatomy underlying telencephalic sensorimotor processes in birds

This paper reviews the organization of the avian and mammalian striatum. The striatum receives input from virtually the entire rostrocaudal and mediolateral expanse of the cerebral cortex. The corticostriatal projections appear to be glutamatergic, forming excitatory synapses in the striatum. Another major projection to the avian striatum that also appears to be glutamatergic stems from a set of nuclei in the dorsal zone of the avian thalamus that are comparable to the mammalian intralaminar, mediodorsal, and midline nuclei. Furthermore, the striatum receives a massive projection from dopaminergic neurons of the ventral tegmental area and substantia nigra in the midbrain tegmentum. In return, the midbrain tegmentum receives a direct GABAergic/substance P-ergic/ dynorphinergic projection from the striatum, as well as an indirect one formed by GABAergic/substance P-ergic/ dynorphinergic and GABA-ergic/enkephalinergic striatal neurons projecting to the pallidum in the first step, and pallidal GABAergic/LANT6/parvalbumin neurons projecting to the midbrain tegmentum in the second step. In addition to its projection neurons, the striatum possesses GABAergic and cholinergic interneurons. One motor output pathway of the striatum runs via the pallidum and dorsal thalamic ventral tier nulei to the motor cortex. In addition to this pathway, birds possess a major descending pathway from the basal ganglia to the tectum via the GABAergic nucleus spiriformis lateralis in the pretectum. On hodological and topological grounds, similar nuclei, although not GABAergic, can be found in mammals. Finally, an other striatal motor output is formed by a sequential GABAergic pathway from the basal ganglia via the substantia nigra to the tectum. In conclusion, it appears that the organization of the avian and mammalian basal ganglia is similar rather than different.     

Elastic constants and thermal expansivity of gel-spun polyethylene fiber and its composites

The five independent stiffness constants, C₁₁, C₃₃, C₄₄, C₆₆, and C₁₃, and the axial and transverse thermal expansivity of unidirectional gel-spun polyethylene fiber reinforced composites have been measured as functions of fiber volume fraction V_f. The axial extensional modulus C₃₃ and axial Poisson's ratio v₁₃ follow the rule of mixtures, while the axial shear modulus C₄₄, transverse shear modulus C₆₆, and transverse plane-strain bulk modulus C_t ( = C₁₁ − C₆₆) obey the Halpin-Tsai equation. Extrapolation to V_f = 1 gives the five stiffness constants of gel-spun polyethylene fiber. The tensile property of the fiber is highly anisotropic, with the axial Young's modulus about 40 times higher than the transverse Young's modulus. In contrast, the axial shear modulus exceeds the transverse shear modulus by only 5%. A similar treatment of the thermal expansivity data in terms of the Schapery equations gives an axial thermal expansivity of −1.25 × 10⁻⁵ K⁻¹ and a transverse thermal expansivity of 11.7 × 10⁻⁵ K⁻¹ for the fiber.     

The existence of a soluble plasmalogenase in guinea pig tissues

The distribution of plasmalogenase for the hydrolysis of 1-alkenyl-2-acyl-sn-glycero-3-phosphoethanolamine (plasmenylethanolamine) in the subcellular fractions of guinea pig tissues was examined. Plasmalogenase activity was found in high abundance in the cytosolic fractions of the brain and the heart. Assessment of microsomal marker enzyme activities in the cytosolic fraction revealed that plasmalogenase activity in the cytosol was not due to microsomal contaminations. The characteristics of the cytosolic plasmalogenase were very similar to the microsomal enzyme with respect to the pH profile of the reaction, the presence of divalent cations and K_m values for plasmenylethanolamine. However, the cytosolic enzyme was slightly less stable at 55°C than the microsomal enzyme. Cytosolic enzyme activity was eluted as a broad peak in Sepharose 6B chromatography with an average molecular weight of 250,000. Our results demonstrate that most of brain plasmalogenase activity is soluble which makes the brain cytosol an excellent source to initiate the purification of this enzyme.     

Film-pore diffusion models—analytical and numerical solutions

The sorption of acid dyes from aqueous effluents onto activated carbon has been studied. The effects of initial dye concentration and activated carbon mass on the rate of Acid Blue 80 and Acid Yellow 117 removal have been investigated. Three mass transport models based on film and pore diffusion control have been applied to model the experimental concentration decay curves. The models are compared on the basis of the solid-phase loading capacity using various assumptions since the assignment of an appropriate solid-phase loading has been the subject of several papers on this topic and no comparisons have been provided on the effectiveness of each approach. The equilibrium solid-phase concentration is assumed: (i) incorporating a time-dependent solid-phase concentration Y_e,t, (ii) equal to the intersection point of the equilibrium isotherm and the operating line and (iii) the point on the equilibrium isotherm where the liquid-phase concentration equals the initial concentration in the film-pore diffusion model.     

Syntheses of nano-multilayered TiN/TiSiN and CrN/CrSiN hard coatings

Nano-structured superhard coatings represent the state-of-the-art in the rapidly increasing worldwide market for protective coatings. In this study, the combination of nano-composite and nano-multilayered structures into the same coating was attempted. Nano-multilayered coatings of TiN/TiSiN and CrN/CrSiN were deposited on tool steel substrates by closed-magnetic-field unbalanced DC magnetron sputter ion plating. The coating structures were characterized using X-ray diffraction, atomic force microscopy, and scanning electron microscopy. Mechanical characterizations were performed including nano-hardness measurement, progressively-increasing-load scratch test, and wear test. TiN/TiSiN coatings have a nano-hardness of 40.2 GPa, whereas CrN/CrSiN coatings have a hardness of 30.9 GPa. TiN/TiSiN coatings also showed a higher critical failure force and scratch fracture toughness as well as better wear resistance and lower acoustic emission signal, indicating less total damage to the coatings.     

一个行业就有一种创新

你眼中的中国元素是什么?中国文化历史悠久,对于民族及生活文化更具有独特的气息。中国元素是被中国人认同的、凝结着中华民族传统文化精神,并体现民族的形象、符号或风俗习惯,保持中国文化象征性,均可被视为中国元素,包括少数民族、剪纸工艺、12生肖、舞龙舞狮等,我个人最爱的是剪纸。你印象最深的一件运用中国元素创作的作品是什么?在2009年,Qee制作了一只2.5英寸的剪     

生物质对低浓度染料废物的协同多层吸收(英文)

Due to the high cost of adsorbents and their thermal regeneration in recent years,much research has focused on the search for cheaper adsorbents for treating wastewater from textile industry.The single component adsorption of an acidic dye,Acid Yellow 117,and a basic dye,Methylene Blue,onto several adsorbents—bamboo,waste wood,bamboo char,waste wood char,bamboo activated carbon,wood activated carbon and active carbon F400 were conducted.Based on a Langmuir analysis,the monolayer adsorption capacities were determined.Three of the adsorbents were selected for binary layer adsorption to check the multilayer concept and the potential application for better adsorbent usage.The two cheapest adsorbents,bamboo and wood are compared with the commercial activated carbon F400,and all three systems were successful.     

Optimization of C/TiCx duplex diffusion barrier coatings for SiCf/Ti composites based on interfacial structure evolution exploration

Introducing a carbon single coating is a popular method used to protect SiC_f/Ti composites from severe interface reactions. However, carbon coatings lose their protective effect on SiC fibres at high temperature, even after a short period time. As such, given the strong demand for high temperature applications in aeronautics and astronautics a more coating which is more effective at high temperatures is desirable. In order to improve the high temperature interfacial stability of SiC_f/Ti composites, a C/TiC_x duplex coating system with different C contents in TiC_x was introduced to explore the protection of fibres at 1200?°C for 1?h. The results show that the C/quasi-stoichiometric TiC coating system protects the SiC fibres most effectively. Based on insights from the evolution of the interface structure, TiC_x has been identified as an interfacial reaction product from the C single coating, exhibiting a gradient in C content and grain size, which is different from a deposited TiC layer with a well-distributed composition and structure. The different coating structure gives rise to different ability to resist C diffusion at high temperatures, in which poor resistance ability appears in TiC_x interfacial reaction layer coming from C single coating due to short-circuit diffusion in C-rich fine-grained TiC layer and fast intracrystalline diffusion trigged by amounts of vacancies in sub-stoichiometric coarse-grained TiC layer. Therefore, C/quasi-stoichiometric TiC duplex coatings with a thick, coarse-grained quasi-stoichiometric TiC layer could effectively inhibit C diffusion by comparison to C single coatings, and is more effective than C/rich-carbon TiC duplex coatings due to the existence of short-circuit diffusion in the latter. As such, C/quasi-stoichiometric TiC duplex coatings appear to be an optimal diffusion barrier for SiC_f/Ti composites at high temperature.