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A detailed analysis of the influence of thermal nonequilibrium on transport in semiconductors was carried out. Special attention was paid to the effect of this nonequilibrium on recombination and the space charge. In particular, recombination has the same mathematical expression for band-to-band and Shockley–Read–Hall transitions; the only difference between the expressions of these recombination mechanisms is a different lifetime. For both types of recombination, the space charge and homogeneity in space nonequilibrium temperature do not affect charge transport, but it modifies, of course, the electron and hole concentrations in nonequilibrium conditions. The lifetime can be introduced only for band-to-band recombination under the quasineutrality condition. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) films were simultaneously synthesized by an ultrasonic spray pyrolysis (USP) method on p-type Si (100), silicon carbide polytype [6H-SiC (0001)], porous 6H-SiC and amorphous glass substrates with the aim of studying the impact of substrate types on the structure and emission of ZnO nanocrystalline films. Porous silicon carbide (P-SiC) was prepared by the electrochemical anodization method at a constant potential of 20 V and etching time of 12 min. ZnO films grown on the SiC and P-SiC substrates are characterized by a wurtzite crystal structure with preferential growth along the (002) direction and with grain sizes of 90-180 and 70-160 nm, respectively. ZnO films grown on the Si substrate have just some small irregular hexagonal islands. The amorphous glass substrate did not promote the formation of any regular crystal forms. The obtained x-ray diffraction and photoluminescence (PL) results have shown that the better ZnO film crystallinity and high PL intensity of near-band edge emissions were achieved in the films grown on the porous SiC and SiC substrates. The preferential growth and crystalline nature of ZnO films on the SiC substrate have been discussed from the point of view of the lattice parameter compatibility between ZnO and SiC crystals. [ABSTRACT FROM AUTHOR]

Purpose: We compared biochemical control and quality of life with intermittent (6 months) versus continuous (36 months) androgen deprivation therapy (ADT) in a non-inferiority randomized phase 3 trial in patients with biochemical failure (BF) after external beam radical radiotherapy (EBRT). Materials and methods: Patients were stratified according to the Gleason score (GS) and were classified as low risk with a GS < 6 and 7 (3 + 4) and high risk with a GS of 7 (4 + 3) and >7. Patients were followed with PSA determinations and quality-of-life assessments (QLQ C-30 and QLQ PR-25) every 6 months for a period of 3 years. BF after radiation was defined as a PSA level of nadir +2 ng/ml. Disease progression (DP) after ADT was defined as PSA ≥4 ng/ml (BF) and/or metastases. Results: Seventy-seven patients were included in this multicenter phase 3 trial from 2005 to 2009. Thirty-eight and 39 patients were included in the intermittent and continuous groups, respectively. The median follow-up for both groups was 48 months (40-68). DP after ADT in the intermittent group was seen in three patients (distant metastases in one patient) versus 0 in the continuous group. The QLQ-C30 and QLQ PR-25 scores did not show any statistically difference between the two ADT groups. Conclusions: No significant differences were seen in DP and QLQ between intermittent (6 months) and continuous (36 months) ADT in patients with BF after EBRT. [ABSTRACT FROM AUTHOR]

Binary metal oxides with different degrees of covalent/ionic character of the oxygen-metal bond are tested as a partial coating of glassy carbon electrode surfaces. The electrocatalytic and antifouling properties of the resulting bicomponent electrode systems are analysed in view of possible applications in different fields of electrochemistry, such as electroremediation and electroanalysis. Based on the performance with respect to oxidation of ascorbic acid, as to sensitivity, repeatability of the responses, and activation of electrocatalytic oxidation, CeO has been preferred. This same electrode system has been further studied in respect to a trickier electrochemical process, namely the anodic oxidation of a chlorophenol derivative, which induces massive passivation of bare electrode surfaces. The effectiveness of the bicomponent electrode system in anodic oxidation of 2,4,6-trichlorophenol has been ascertained, over a wide range of concentrations, by comparison with pure glassy carbon surfaces. [ABSTRACT FROM AUTHOR]

As is well known, the metallurgical microstructure of carbon steel is formed by ferrite and pearlite after the annealing heat treatment. When the cooling rate increases, the diffusive process is interrupted causing a change in the metallurgical microstructure which will affect steel properties. The aim of this work was to study thermal, structural, and microstructural properties of annealed carbon steel samples with four different carbon contents. Crystalline structure and crystalline quality were studied by the X-ray diffraction technique, where the full width at half maximum analysis showed that as the carbon content increased, the crystalline quality decreased. The metallurgical microstructure morphology was studied by scanning electron microscopy. The thermal diffusivity and the heat capacity were determined by the photoacoustic technique and by the thermal relaxation method, respectively. The thermal diffusivity and the thermal conductivity decreased as the carbon content increased. The amplitude signal of photothermal radiometry increased as the carbon content increased, while the phase signal of photothermal radiometry did not show significant differences among studied carbon steel types. The photoacoustic technique represents an important alternative in the steel characterization field. [ABSTRACT FROM AUTHOR]

The article discusses research that defined the expression of PD-L1 and PD-1 in clonal PCs and T and natural killer (NK) cells on bone marrow (BM) aspirates from monoclonal gammopathy of undetermined significance (MGUs) and multiple myeloma (MM) patients at diagnosis following treatment and upon relapse using standardized multidimensional flow cytometry (MFC). It suggests that PD-L1 can operate as an immune checkpoint in the tumor microenvironment.

In total, 17 pediatric patients with hematologic malignancies (n=14) and Fanconi anemia (FA) (n=3) underwent haploidentical SCT with T-cell depletion. The patients were conditioned with reduced-intensity regimens, and CYA was used for GVHD prophylaxis. Successful engraftment occurred in 16 patients (94%). One patient failed to achieve a primary engraftment. Another patient rejected the first SCT after 10 weeks and had a successful second transplant. Of all engrafted patients, only one developed severe acute GVHD. Ten patients were alive at a median follow-up of 18 months (range, 5-62 months). The 5-years' OS was 53.8%. The three patients with FA are currently well with full-donor chimerism at 16, 6 and 5 months post transplant, respectively. The OS of 14 patients with high-risk hematologic malignancies was 47.6%. Three patients died as a result of post transplant leukemia relapse. CMV infection, GVHD and organ injury were other causes of mortality. Haploidentical SCT was found to be an alternative feasible treatment in Uruguay for patients who need allogenic transplantation but lack an HLA-identical family donor. It should be considered as an early option in FA patients before transformation or significant exposure to blood products. [ABSTRACT FROM AUTHOR]

Silicon is more than the dominant material in the conventional microelectronics industry: it also has potential as a host material for emerging quantum information technologies. Standard fabrication techniques already allow the isolation of single electron spins in silicon transistor-like devices. Although this is also possible in other materials, silicon-based systems have the advantage of interacting more weakly with nuclear spins. Reducing such interactions is important for the control of spin quantum bits because nuclear fluctuations limit quantum phase coherence, as seen in recent experiments in GaAs-based quantum dots. Advances in reducing nuclear decoherence effects by means of complex control still result in coherence times much shorter than those seen in experiments on large ensembles of impurity-bound electrons in bulk silicon crystals. Here we report coherent control of electron spins in two coupled quantum dots in an undoped Si/SiGe heterostructure and show that this system has a nuclei-induced dephasing time of 360 nanoseconds, which is an increase by nearly two orders of magnitude over similar measurements in GaAs-based quantum dots. The degree of phase coherence observed, combined with fast, gated electrical initialization, read-out and control, should motivate future development of silicon-based quantum information processors. [ABSTRACT FROM AUTHOR]

In this research quaternary alloy thin films made of Cu, CdTe, and O have been grown and characterized. The samples used in this investigation were grown simultaneously by reactive RF co-sputtering and by introducing oxygen and argon in the chamber during growth and changing the power in the Cu target from 10 W to 50 W. The carrier distribution as a function of the position was studied by using energy dispersive spectroscopy-scanning electronic microscopy (EDS-SEM), micro-Raman spectroscopy, and photocarrier images. Structural characterization was carried out by using X-ray diffraction. According to the results, a lateral carrier distribution was found in all samples and a new phase identified as CuTe was revealed for samples grown at 50 W. [ABSTRACT FROM AUTHOR]

Nanotubes and nanowires have sparked considerable interest in biosensing applications due to their exceptional charge transport properties and size compatibility with biomolecules. Among the various biosensing methodologies incorporating these nanostructured materials in their sensing platforms, liquid-gated field-effect transistors (LGFETs)-based device configurations outperform the conventional electrochemical measurements by their ability in providing label free, direct electronic read-out, and real-time detection. Together with integration of a microfluidic channel into the device architecture, nanotube- or nanowires-based LGFET biosensor have demonstrated promising potential toward the realization of truly field-deployable self-contained lab-on-chip devices, which aim to complement the existing lab-based methodologies. This review addresses the recent advances in microfluidic-integrated carbon nanotubes and inorganic nanowires-based LGFET biosensors inclusive of nanomaterials growth, device fabrication, sensing mechanisms, and interaction of biomolecules with nanotubes and nanowires. Design considerations, factors affecting sensing performance and sensitivity, amplification and multiplexing strategies are also detailed to provide a comprehensive understanding of present biosensors and future sensor systems development. [ABSTRACT FROM AUTHOR]

The primary productivity of the Salton Sea, California is excessively high, leading to low-oxygen conditions, low clarity, and odors associated with algal decomposition. Treating the inflow water with aluminum sulfate (alum) to remove soluble phosphorus (P), the limiting nutrient, is being considered to improve water quality. The objective of this study was to evaluate the use of alum to remove dissolved phosphorus from New River water, and the potential for the Al-bound P to be released into the Salton Sea. The New River is dominated by agricultural wastewater and has a salinity somewhat higher than normally encountered for alum treatment (total dissolved solids = 2,300 mg l−1), thus, evaluation of alum’s effectiveness is needed. In addition, alum may be dosed directly into the New River and the floc allowed to flow into the Salton Sea if the precipitated P is stable in Salton Sea water. In this study, we evaluated the potential for floc-bound P to be desorbed in Salton Sea water, which has an unusually high salinity (46 g l−1). Aluminum at a 5-mg l−1 dose was effective in removing over 90% of the soluble phosphorus from the New River water. However, when the alum floc was added to Salton Sea water, up to 100% of the Al-bound P was released into the Sea water due to desorption, dissolution, and recrystallization of the alum floc. These results indicate that treatment of agricultural drainage water to reduce P-loading can be effective if the alum floc is settled and not allowed to enter the saline Salton Sea. In addition to alum costs, estimated at US$13 million year−1, settling basin construction and maintenance for floc removal would be required. [ABSTRACT FROM AUTHOR]

The Salton Sea is a hypereutrophic, saline lake in the desert of southern California. Like many lakes, the primary productivity of the Sea is limited by phosphorus. However, unlike most lakes, the release of P from the sediments is not controlled by the reductive dissolution of Fe(III)-oxide minerals. Most of the iron in the sediments of the Salton Sea is present as Fe(II)-sulfides and silicates. Rather, the sediments are dominated by calcite which is actively precipitating due to alkalinity production via sulfate reduction reactions. We hypothesized that calcite could be an important sink for phosphorus released from the decomposing organic matter. In this work we evaluated the potential for phosphate to coprecipitate with calcite formed in simulated Salton Sea sediment pore water. At calcite precipitation levels and P concentrations typical for the Salton Sea pore water, coprecipitation of P removed 82–100% of the dissolved phosphorus. The amount of P incorporated into the calcite was independent of temperature. The results of this work indicate that the internal loading of P within the Salton Sea is being controlled by calcite precipitation. Management of external P loading should have an immediate impact on reducing algae blooms in the Salton Sea. [ABSTRACT FROM AUTHOR]

Human keratinocytes are exposed to strong physical changes, and have the potentiality to react to external stimuli by switching on adaptation mechanisms. In hyperosmotically shocked keratinocytes a rapid and strong increase in calcium has been observed. We showed that this increase could not be prevented by growing the cells in medium devoid of calcium and in the presence of EGTA, indicating that the intracellular calcium increase was due to delivery from internal stores. Further, we observed an increased synthesis of dyacylglycerol and inositol trisphosphates after shock, suggesting that phospholipase C mediates both events. Our experiments demonstrated that osmotic shock in human keratinocytes leads to activation of phospholipase C-γ1, as measured using an in vitro assay system. This activation is independent of protein tyrosine phosphorylation and corresponded to a relocation of the enzyme to perinuclear membranes as shown by immunofluorescence. [ABSTRACT FROM AUTHOR]

Focuses on the presence of the serine protease Omi in the supernatant of isolated mitochondria exposed to recombinant truncated Bid. Amino acid sequence; Interaction between endogeneous Omi and recombinant XIAP.

A hallmark of apoptosis is the fragmentation of nuclear DNA. Although this activity involves the caspase-3-dependent DNAse CAD (caspase-activated DNAse), evidence exists that DNA fragmentation can occur independently of caspase activity. Here we report on the ability of truncated Bid (tBid) to induce the release of a DNAse activity from mitochondria. This DNAse activity was identified by mass spectrometry as endonuclease G, an abundant 30 kDa protein released from mitochondria under apoptotic conditions. No tBid-induced endonuclease G release could be observed in mitochondria from Bcl-2-transgenic mice. The in vivo occurrence of endonuclease G release from mitochondria during apoptosis was confirmed in the liver from mice injected with agonistic anti-Fas antibody and is completely prevented in Bcl-2 transgenic mice. These data indicate that endonuclease G may be involved in CAD-independent DNA fragmentation during cell death pathways in which truncated Bid is generated. [ABSTRACT FROM AUTHOR]

Here we demonstrate a novel approach to the complete removal of threading dislocations in ZnSe on GaAs (001). This approach, which we call patterned heteroepitaxial processing (PHP), involves post-growth patterning and thermal annealing. Eyitaxial layers of ZnSe on GaAs (001) were grown to thicknesses of 2000–6000 A by photoassisted metalorganic vapor phase epitaxy (MOVPE). Following growth, layers were patterned by photolithography and then annealed at elevated temperatures under flowing hydrogen. Threading dislocation densities were determined using a bromine/methanol etch followed by microscopic evaluation of the resulting etch pit densities. We found that as-grown layers contained more than 107 CM-2 threading dislocations. The complete removal of threading dislocations was accomplished by patterning to 70 gm by 70∼tm square regions followed by thermal annealing for 30 minutes at temperatures greater than 5000C. Neither post-growth annealing alone nor post-growth patterning alone had a significant effect. The effectiveness of this approach dminishes significantly below 500 C so that annealing at 400 C produces no measurable effect. We propose that the underlying mechanism for dislocation removal is the thermally activated glide of dislocations to the sidewalls of patterned regions, as promoted by sidewall image forces. [ABSTRACT FROM AUTHOR]

Insulin-dependent diabetes mellitus (IDDM) is associated with autoantibodies to several pancreatic islet antigens. We have described an assay in which autoantibodies displace a radiolabelled monoclonal anti-islet antibody. Sera from 87 % of 429 children at time of diagnosis of IDDM were positive, while sera from control groups had much lower prevalences (1.3-19 %). Sera from 41.9 % of diabetic subjects remained positive after 20 years duration of IDDM. Sera from 23.6 % of parents and 37.9 % of non-diabetic siblings were positive. Twenty relatives who subsequently developed IDDM had the same prevalence of the antibodies (85 %) as did the patients at time of diagnosis. These findings confirm that the autoantibodies detected by monoclonal antibody (mAb) 1A2 are common at the onset of IDDM and their presence prior to the onset of hyperglycaemia suggests that this method may be useful in screening non-diabetic populations. The high prevalence of antibodies in relatives reduces the efficacy for diabetes prediction, but suggests either that generation of these antibodies is an autosomal dominant trait, or that the antigen detected by these antibodies is cross-reactive with a common environmental antigen. Differentiation between these hypotheses will await the identification of the specific islet-cell antigen detected by mAb 1A2. [Diabetologia (1996) 39: 1365-1371] [ABSTRACT FROM AUTHOR]

Copyright of Materiaux et Constructions is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The early suggestion by Lozier and Butler ( Photochem. Photobiol. 17, 133-137 (1973)) that EPR Signal II arises from radicals associated with the water-splitting process in PSII has been confirmed and extended over the intervening years. Recent work has identified the Signal II radicals, $$\begin{array}{*{20}c} {\mathop D\nolimits^{\begin{array}{*{20}c} + \\ . \\ \end{array} } } \\ \end{array}$$ and $$\begin{array}{*{20}c} {\mathop Z\nolimits^{\begin{array}{*{20}c} + \\ . \\ \end{array} } } \\ \end{array}$$ , with plastosemiquinone cation species. In the experiments presented here we have used ENDOR spectroscopy and DO/HO exchange to characterize these paramagnets in more detail. The ENDOR matrix region, which arises from protons which interact weakly with the unpaired electron spin, is well-resolved at 4 K and at least seven resonances are apparent. A number of hyperfine couplings in the 3-8 MHz range are observed and are suggested to arise from methyl or hydroxyl protons which occur as substituents on the plastosemiquinone cation ring or from amino acid protons hydrogen-bonded to the 1,4-hydroxyl groups. Orientation selection experiments are consistent with these possibilities. DO/HO exchange shows that the D/Z site is accessible to solvent. However, the exchange occurs slowly and is not complete even after 72 hours which suggests that the free radicals are functionally isolated from solvent water. [ABSTRACT FROM AUTHOR]

The specific binding of [3H]cortisol to plasma membranes purified from mouse liver, studied by the ultrafiltration method, shows the existence of specific binding sites for cortisol. The kinetic parameters of this binding are KD = 4.4 nM and Bmax = 685 fmol/mg protein in presence of 1 microM of corticosterone. With respect to the binding of 4 nM [3H]cortisol to the membrane, the affinities of the steroids decreased in the following order: deoxycorticosterone greater than corticosterone greater than progesterone greater than cortisol greater than prednisolone greater than testosterone greater than 20 beta-hydroxyprogesterone greater than cortisone. Estradiol, dexamethasone, ouabain and triamcinolone acetonide do not have affinity for this binding site. Neither Ca2+ nor Mg2+ affected the binding of [3H]cortisol to the plasma membranes. Likewise, the presence of agonists and antagonists of alpha and beta-adrenergic receptors did not modify the binding of [3H]cortisol. The results suggest that the plasma membrane binding site characterized is more specific for corticoids and is different from nuclear glucocorticoid and progesterone receptors. [ABSTRACT FROM AUTHOR]

Copyright of Materials & Structures is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Zeitschrift für Rechtsmedizin is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Serum amino acids were determined in 22 epileptic children treated with valproic acid. This treatment caused hypocarnitinemia in all, and hyperammonemia in 16. Regardless of the blood ammonia levels, values for glutamic acid, arginine, glycine, serine and alanine were higher than those of normal controls, while aspartic acid and ornithine were lower. These findings suggest that valproate causes intramitochondrial dysfunction of the urea cycle. [ABSTRACT FROM AUTHOR]

Stem cells possess significant age-dependent differences in their immune-response profile. These differences were analysed by Next-Generation Sequencing of six age groups from bone marrow mesenchymal stem cells. A total of 9,628 genes presenting differential expression between age groups were grouped into metabolic pathways. We focused our research on young, pre-pubertal and adult groups, which presented the highest amount of differentially expressed genes related to inflammation mediated by chemokine and cytokine signalling pathways compared with the newborn group, which was used as a control. Extracellular vesicles extracted from each group were characterized by nanoparticle tracking and flow cytometry analysis, and several micro-RNAs were verified by quantitative real-time polymerase chain reaction because of their relationship with the pathway of interest. Since miR-21-5p showed the highest statistically significant expression in extracellular vesicles from mesenchymal stem cells of the pre-pubertal group, we conducted a functional experiment inhibiting its expression and investigating the modulation of Toll-Like Receptor 4 and their link to damage-associated molecular patterns. Together, these results indicate for the first time that mesenchymal stem cell-derived extracellular vesicles have significant age-dependent differences in their immune profiles. [ABSTRACT FROM AUTHOR]