New Process for Recovery of Zinc Sulfate and Sulfuric Acid from Zinc Electrowinning Bleed Solutions

Acid-base couple extractants extract sulfuric acid and zinc sulfate efficiently, selectively and reversibly. Their properties allowed development of a new, solvent extraction process for treating zinc electrowinning waste streams. In this process, about 95% of the sulfuric acid and 95% of the zinc can be recovered at concentrations high enough to be directly recycled to zinc production. Lime consumption and gypsum formation are substantially reduced. Only one extractant is used in the process, and zinc is recovered as zinc sulfate.     

One‐Step Solvent‐Free Synthesis and Characterization of Zn1−xMnxSe@C Nanorods and Nanowires

The carbon‐encapsulated, Mn‐doped ZnSe (Zn_1−xMn_xSe@C) nanowires, nanorods, and nanoparticles are synthesized by the solvent‐free, one‐step RAPET (reactions under autogenic pressure at elevated temperature) approach. The aspect ratio of the nanowires/nanorods is altered according to the Mn/Zn atomic ratio, with the maximum being observed for Mn/Zn = 1:20. A 10–20 nm amorphous carbon shell is evidenced from electron microscopy analysis. The replacement of Zn by Mn in the Zn_1−xMn_xSe lattice is confirmed by the hyperfine splitting values in the electron paramagnetic resonance (EPR) experiments. Raman experiments reveal that the Zn_1−xMn_xSe core is highly crystalline, while the shell consists of disordered graphitic carbon. Variable‐temperature cathodoluminescence measurements are performed for all samples and show distinct ZnSe near‐band‐edge and Mn‐related emissions. An intense and broad Mn‐related emission at the largest Mn alloy composition of 19.9% is further consistent with an efficient incorporation of Mn within the host ZnSe lattice. The formation of the core/shell nanowires and nanorods in the absence of any template or structure‐directing agent is controlled kinetically by the Zn_1−xMn_xSe nucleus formation and subsequent carbon encapsulation. Mn replaces Zn mainly in the (111) plane and catalyzes the nanowire growth in the [111] direction.     

Extracellular Vesicle MicroRNA That Are Involved in β-Thalassemia Complications

Beta thalassemia major (βT) is a hereditary anemia characterized by transfusion-dependency, lifelong requirement of chelation, and organ dysfunction. MicroRNA (miRNA) can be packed into extracellular vesicles (EVs) that carry them to target cells. We explored EV-miRNA in βT and their pathophysiologic role. Circulating EVs were isolated from 35 βT-patients and 15 controls. EV miRNA was evaluated by nano-string technology and real-time quantitative polymerase chain reaction (RT-qPCR). We explored effects of EVs on cell culture proliferation, apoptosis, and signal transduction. Higher amounts of small EV (exosomes) were found in patients than in controls. The expression of 21 miRNA was > two-fold higher, and of 17 miRNA < three-fold lower in βT-EVs than control-EVs. RT-qPCR confirmed differential expression of six miRNAs in βT, particularly miR-144-3p, a regulator of erythropoiesis. Exposure of endothelial, liver Huh7, and pancreatic 1.1B4 cells to βT-EVs significantly reduced cell viability and increased cell apoptosis. βT-EV-induced endothelial cell apoptosis involved the MAPK/JNK signal-transduction pathway. In contrast, splenectomized βT-EVs induced proliferation of bone marrow mesenchymal stem cells (BM-MSC). In summary, the miR-144-3p was strongly increased; βT-EVs induced apoptosis and decreased endothelial, pancreatic, and liver cell survival while supporting BM-MSC proliferation. These mechanisms may contribute to βT organ dysfunction and complications.     

Effect of inorganic constituents on chemical oxygen demand—II. Organic carbon to halogen ratios determine halogen interference

The dependency of free halogen ion oxidation in chemical oxygen demand (COD) assays on the organic content of the sample was investigated. Halogen interference was reduced at increasing glucose or potassium hydrogen phthalate concentration; in each case, a threshold ratio of organic matter to halogen existed, above which halogen oxidation was masked. This ratio depended upon the presence of mercuric sulfate in the case of chloride but not of bromide. It was also affected by the ease of oxidation of both the organic molecule and the halogen ion, as well as by their actual COD. Thus, bromide oxidation was more difficult to prevent than that of chloride, and phthalate exerted a stronger masking effect than glucose.     

Bioengineered Biomimetic and Bioinspired Noninvasive Drug Delivery Systems

The main purpose herein is to provide an up-to-date review on noninvasive biomimetic, bioinspired, and bioengineered drug delivery system (DDS). Noninvasive DDS is an ever-growing field critical for the applicability of drugs. It offers noninvasive administration routes with improved controlled, targeted, and triggered drug delivery. Noninvasive DDS employ many approaches and strategies, such as, nano- and microparticles, lipid-based systems, sonophoresis, electrophoresis and iontophoresis, penetration enhancers, microneedles, and gels. The last decade seen a surge in research papers employing the paradigms of biomimicry, bioinspiration, and bioengineering. However, since the use of these terms in noninvasive DDS field is often inconsistent and unclear, some generalized perspectives are provided on the possible usage of these terms in future publications. Additionally, a critical discussion on the novelty and origins of these paradigms is provided. The advantages and disadvantages of each of the noninvasive routes and their current main limitations are summarized. The main aspects of indicated fields are discussed: The unique physiology of the related tissues, the main hurdles for mass transport, the various DDS tested, and materials selection. Finally, the basic concepts and therapeutic effects of these DDS are discussed and future venues for noninvasive biomimetic, bioinspired, and bioengineered DDS research are proposed.     

Effects of rating format on goal-setting dimensions: A field experiment.

Atotal of 10 managers and their 62 subordinates participated in a field experiment that examined the effects of performance appraisal feedback deriving from two rating formats—behavioral observation scales (BOS) and graphic rating scales—on three goal-setting dimensions. Multivariate analyses of variance and a priori t tests revealed, as hypothesized, that the BOS format yielded significantly higher levels of goal clarity, goal acceptance, and goal commitment, the three goal-setting dimensions. Results are discussed in terms of systemic characteristics, that is, a "built-in" focus on specific behaviors, rather than a translation of generic performance dimensions into specific work behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cytotoxic and interferon gamma-producing activities of gamma delta T cells in the mouse intestinal epithelium are strain dependent

We have analyzed the cytolytic activity of freshly isolated intraepithelial T cells (i-IEL) from the intestines of several different mouse strains in an anti-T-cell receptor monoclonal antibody-mediated redirected lysis assay. The cytolytic activity of gamma delta i-IEL but not that of alpha beta i-IEL was strain dependent. Mouse strains could be divided into high (H), marginal (M), and null (N) strains. The anti-gamma delta T-cell receptor monoclonal antibody-induced interferon gamma production showed the same strain-dependent variability, but the proliferative responses to gamma delta T-cell receptor crosslinking did not show this variability. The N phenotype of gamma delta i-IEL was found to be dominant in (H x N)F1 mice. In radiation bone-marrow chimeras the H/N phenotype was determined by the genotype of the reconstituting bone-marrow-derived cells but was not determined by the genotype of the radioresistant host cells. Analysis of (H x N)F1 backcross animals indicated that at least two genes are involved in determination of the H/N phenotype. One of these genes is major-histocompatibility-complex linked. No difference in the use of the variable region segment of the gamma-chain or delta-chain was seen between the gamma delta i-IEL from H and N strains. Various models that might explain the strain-dependent gamma delta i-IEL phenotypes are discussed.     

Proposed thermodynamic method to determine the vortex mass in layered superconductors

We describe a simple method to study vortex dynamics that can determine or set an upper limit on the vortex mass. The specific heat of the vortex lattice in layered superconductors has a classical limit of 1 k_B per pancake vortex if the vortex mass is zero. If the vortex mass m_v is finite, a new Einstein branch of normal modes will appear with a crossover temperature E m_v ^–1, and the specific heat will saturate at a new classical limit of 2 k_B per pancake vortex.This work was supported in part by AFOSR under project F49620-92-C-0004 and by NSF under grant DMR 91-20361. We acknowledge helpful discussions with Shoucheng Zhang and S. R. Patel.     

Decidable fragments of many-sorted logic

Many natural specifications use types. We investigate the decidability of fragments of many-sorted first-order logic. We identified some decidable fragments and illustrated their usefulness by formalizing specifications considered in the literature. Often the intended interpretations of specifications are finite. We prove that the formulas in these fragments are valid iff they are valid over the finite structures. We extend these results to logics that allow a restricted form of transitive closure.