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The transient heat conduction equation was used as the microscopic model of the Tian-Calvet microcalorimeter. It was verified by comparing simulated and experimental calorimetric curves and used to guide sample cell design for a faster response time, for which it gave the guidelines to minimize the heat flow distance and use a heat flux that is uniform and onto the whole face of the thermopile sensor. The resulting sample cell was disc-shaped with the sample powder placed in it as a thin 0.2 mm layer on a stainless steel base with a wall thickness of 0.5 mm that covered the whole face of the thermopile on which it was placed. The rise time of the heat response curve to a step change in sample temperature, which is the response time for measuring the differential heat released, was 45 s. The response curve from a gas dose returned to the baseline within 400 s, which is the time needed to measure the integrated heat in a pulsed dosage. The accuracy of the heats measured by the calorimeter was verified by comparison with data in the literature on the adsorption of ethanol and ammonia on HZSM-5 and adsorption of methanol and ammonia on SAPO-34. The differential heat of methanol adsorption on SAPO-34 at 333 K and ammonia adsorption on HZSM-5 at 423 K were measured by both the conventional discontinuous procedure and a new continuous procedure. In the continuous procedure, gas was continuously dosed at a very slow flow rate that was kept slow enough for the gas and adsorbate to reach quasi-equilibrium. The continuous procedure has the advantages of high resolution results and a simpler experimental procedure, and a calorimetric curve could be measured within 3 h. [ABSTRACT FROM AUTHOR]

We have fabricated a GaAs-based triangular-barrier photodiode, in which self-assembled InGaAs quantum rods (Q-rods) are embedded in its barrier region. Transport study at 100 K has shown that electrons start to flow mainly through Q-rods when a bias is set above a threshold. Upon illumination, photo-generated holes are found to accumulate in the middle portion of Q-rods and efficiently lower the local barrier height, yielding the responsivity as high as 105A/W at the incident light of 1 fW. [ABSTRACT FROM AUTHOR]

Based on two summer spatio-temporal data sets obtained from the northern South China Sea shelf and basin, this study reveals contrasting relationships among bacterial production (BP), dissolved organic (DOC) and primary production (PP) in the transition zone from the neritic to the oceanic regions. Inside the mid-shelf (bottom depth <100m), where inorganic nutrient supplies from river discharge and internal waves were potentially abundant, BP, DOC and PP were positively intercorrelated, whereas these three measurements became uncorrelated in the oligotrophic outer shelf and slope. We suggest that the availability of limiting minerals could affect the couplings/decouplings between the source (i.e. phytoplankton) and sink (i.e. bacteria) of organic carbon, and thus DOC dynamics. DOC turnover times were homogeneously low (37-60 days) inside the mid- shelf area and then increased significantly to values >100 days in the outer shelf, indicating that riverine (Pearl River) DOC might be more labile. The actual mechanism for this is unknown, but might relate to higher inorganic nutrient supply from river/terrestrial sources. The positive correlation of the BP / PP ratios vs. phosphate (and nitrate) concentrations in the inner shelf implies that if anthropogenic mineral loading keeps increasing in the foreseeable future, the near-shore zone may become more heterotrophic, rendering the system a stronger source of CO2. [ABSTRACT FROM AUTHOR]

The present paper describes a metal-metal bonding technique using Cu nanoparticles containing Ag nanoparticles (Ag/Cu nanoparticles). The Ag/Cu nanoparticles with particle sizes of 30-85 nm and crystal sizes of 9.3 nm for Cu and 8.1 nm for Ag were produced by reducing 5.0×10-3 M Ag+ (AgClO4) and 5.0×10-3 M Cu2+ (Cu(NO3)2) simultaneously with 1.0 M hydrazine in aqueous solution containing 1.0 g/L poly(vinylpyrrolidone) as dispersing agent and 5×10-3 M citric acid as stabilizer at room temperature. Discs of metallic Cu or metallic Ag were successfully bonded under annealing at 400°C and pressurizing at 1.2 MPa for 5 min in H2 gas with help of the Ag/Cu particles. The shear strengths required for separating the bonded discs were as large as 19.7 for the Cu discs and 16.0 MPa for the Ag discs [ABSTRACT FROM AUTHOR]

Abstract  The amino acid R or K at position 333 on the glycoprotein of the rabies virus is considered necessary for virulence in adult mice. Although some exceptions exist, substitution at this position causes expression of a phenotype that is either less pathogenic or non-virulent. To date, such substitutions have only been found in fixed strains of rabies virus. In this study, the authors found 333H, 333N, and 333Q substitutions at this position in rabies virus street strains isolated from non-hematophagous bats in Brazil. These strains showed pathogenicity and lethality on passage using adult mice with the intracerebral route and were confirmed rabies-positive by immunofluorescent assay. This suggests that these strains maintain virulence. Our findings indicate that rabies virus street strains with these substitutions exist in the field and may result in infection cycles. [ABSTRACT FROM AUTHOR]

We have investigated the electronic transport properties of resistivity, magnetoresistance and the Hall effect on epitaxial and polycrystalline Fe3Si thin films. The electrical transport measurements reveal the microstructure which has not been clarified from x-ray diffraction and/or scanning electron microscopy. We show that (1 0 0)-oriented epitaxial film 36 nm thick on MgO(1 1 1) exhibits ferromagnetic-tunnelling conduction, (1 1 0)-oriented epitaxial film 36 nm thick on yttria stabilized zirconia [YSZ(1 1 1)] is in a percolated region, and polycrystalline film 36 nm thick on Al2O3(1 1 0) and (1 0 0)-oriented epitaxial film 150 nm thick on MgAl2O4(1 0 0) have metallic conduction. These results imply that the electrical transport measurements are a powerful tool for evaluating the microstructure of the samples. The coefficients of the skew and the side-jump scatterings in the extraordinary Hall effect, and the quadratic temperature coefficient of resistivity observed on (1 0 0)-oriented epitaxial film 150 nm thick on MgAl2O4 show that Fe3Si is a ferromagnetic metal where the effective electron mass is slightly enhanced compared with Fe, Co and Ni due to the electron-electron correlation. [ABSTRACT FROM AUTHOR]

Background. There are many reports of incompletely glycosylated O-linked oligosaccharides on the IgA1 hinge region in certain IgA nephropathy patients. In addition, other reports have noted a relationship between tonsillectomy and IgA nephropathy. Methods. Immunoglobulins from extracts of tonsillectomized tissue and other sources were analysed by isoelectric focusing (IEF) and by enzyme-linked immunosorbent assay (ELISA). Results. The IEF profile of tonsillar IgA differed from that of serum IgA and it was enriched in cationic IgA. However, extracts from tonsillitis controls and IgA nephropathy patients exhibited profiles that were very similar. Enzymatic removal of sialic acid induced a shift of the peaks to the cathode side. The profiles of IgA from treated tonsillar extract and treated serum were closely overlapped. In addition, asialo Galβ1,3GalNAc was clearly present in cationic IgA from tonsillar extract and in aberrant IgA1 from serum following enzymatic transfer of sialic acid to IgA1. Serum IgA also contained partly sialylated IgA1. Quantitative analysis of IgA and IgG in the extracts indicated that IgA was significantly higher, whereas IgG was significantly lower in IgA nephropathy patients. Conclusions. We found that the IgA1 produced in tonsillar tissue differed from serum IgA1. Furthermore, an overproduction of asialo IgA1 resulted from the disordered balance between IgA- and IgG-producing cells in the tonsils from the IgA nephropathy patient. Although it is unclear how such asialo IgA1 molecules are transferred from tonsil tissue to serum, a tonsillar source may produce a few micrograms of aberrant IgA1 that then appears in serum. [ABSTRACT FROM AUTHOR]

A new ordered fullerene phase encapsulated by large-diameter CNTs is systematically investigated by combining a growth technique by chemical vapour deposition, high-resolution transmission electron microscopy and molecular-dynamics simulations. In contrast to fullerenes in smaller (1-2 nm) diameter CNTs, where fullerenes are packed in linear or helical chains, fullerenes form a nanoscale cylinder in double-walled CNTs with diameters of [?]4 nm. The fullerenes were shown to form a nanocylinder with a side wall that resembled the (111) plane of solid C60. This ordered phase is different from peapods or fullerene solids known so far, and a result of the interaction between the CNT wall and fullerenes. This finding will open up a new field of fullerene science. [ABSTRACT FROM AUTHOR]

Most culture media for in vitro production (IVP) of porcine embryos contain serum or bovine serum albumin (BSA); especially in the case of in vitro maturation (IVM) porcine follicular fluid is added. The present study was carried out to establish porcine-defined IVP. In Experiment 1, we investigated the efficacy of additional 0.6 mM cystine, 100 M cysteamine (Cys), or cystine + Cys to a defined TCM-199 maturation medium with regard to the developmental competence of in vitro-matured porcine oocytes following intracytoplasmic sperm injection (ICSI). The control medium was a modified TCM-199 containing 0.05% (w/v) polyvinyl alcohol (PVA). In Experiment 2, the effect of epidermal growth factor (EGF) addition to a modified porcine zygote medium (mPZM) for in vitro culture (IVC) medium was investigated on embryonic development following ICSI. As positive and negative controls, 0.3% BSA (mPZM-3) or 0.3% PVA (mPZM-4), respectively, was added to the basic medium. Five or 10 ng mL-1 of EGF was supplemented in the negative control medium (mPZM-4). All percentage data on cleavage and blastocyst development were subjected to arcsine transformation before statistical analysis using the STATVIEW program (Abacus Concepts, Berkeley, CA). The mean cell numbers per blastocyst (assessed by Giemsa staining method) were analyzed by one-way ANOVA, and the differences among the groups were also analyzed using Tukey-Kramer multiple comparison tests. In Experiment 1, there were no significant differences in the rates of cleavage (31.4 to 64.3%) and blastocyst formation (6.5 to 22.9%) among the treatment and control groups. The mean cell numbers per blastocyst ranged from 30 to 48 among the groups, without significant differences. In Experiment 2, the rates of cleavage (43.0 to 58.0%) and blastocyst formation (14.0 to 23.6%), and the mean cell numbers per blastocyst (30 to 37) were not significantly different among the groups. However, the addition of 5 ng mL-1 of EGF to the mPZM-4 resulted in a significantly (P d 0.05) higher blastocyst rate (48.6%) to cleaved embryos than the other two defined groups (mPZM-4 and mPZM-4 with 10 ng mL-1 EGF: 23.4% and 23.1%, respectively), but not significantly different with mPZN-3 (40.1%). The present results indicate that TCM-199 with added cysteamine (100 M) can be used as a defined IVM medium for porcine oocytes, and further addition of cystine into the IVM medium is not necessary. The addition of 5 ng mL-1 of EGF to a defined IVC medium enhanced subsequent development after ICSI. These results show that porcine blastocysts can be produced by defined media throughout the steps of IVP (IVM, ICSI, and IVC).This study was partly supported by a grant-in-aid for Scientific Research (17580242) from the Japan Society for the Promotion of Science. [ABSTRACT FROM AUTHOR]