Effect of Silicon on Hot Shortness in Fe-Cu-Ni-Sn-Si Alloys During Isothermal Oxidation in Air

Residual Cu in scrap-based EAF steel leads to a surface-cracking phenomenon known as surface hot shortness. Si is known to provide a potential reduction in hot shortness; however, the mechanisms involved are not fully understood for low Si quantities. The current study aims to determine a window of Si contents with a given Ni content needed to counteract the negative effects of Sn and Cu to reduce hot shortness and to determine the mechanism. Thermogravimetric analysis (TG), SEM-EDS, XRD, and TEM were used to study the hot shortness behavior of Fe containing 0.2 pct Cu, 0.05 pct Ni, 0.01 pct Sn and with varying Si-content (0.02 pct, 0.1 pct, 0.15 pct, and 0.2 pct Si). It was found that the fayalite formation resulting in a reduction of oxidation and consequently liquid Cu formation occurred for all Si contents examined. The range of Si contents between 0.1 and 0.2 wt pct Si exhibited a mechanism that was a combination of fayalite formation impeding oxidation as well as occlusion of the Cu-rich liquid. This range was acceptable to alleviate hot shortness.     

Ferroelasticity in a metal–organic framework perovskite; towards a new class of multiferroics

A metal–organic framework perovskite, [(CH₂)₃NH₂][Mn(HCOO)₃], exhibits a weakly first order ferroelastic phase transition at ～272 K, from orthorhombic Pnma to monoclinic P2₁/n, and a further transition associated with antiferromagnetic ordering at ～8.5 K. The main structural changes, through the phase transition, are orientational ordering of the azetidium groups and associated changes in hydrogen bonding. In marked contrast to conventional improper ferroelastic oxide perovskites, the driving mechanism is associated with the X-point of the cubic Brillouin zone rather than being driven by R- and M-point octahedral tilting. The total ferroelastic shear strain of up to ～5% is substantially greater than found for typical oxide perovskites, and highlights the potential of the flexible framework to undergo large relaxations in response to local structural changes. Measurements of elastic and anelastic properties by resonant ultrasound spectroscopy show some of the characteristic features of ferroelastic materials. In particular, acoustic dissipation below the transition point can be understood in terms of mobility of twin walls under the influence of external stress with relaxation times on the order of ～10^?7 s. Elastic softening as the transition is approached from above is interpreted in terms of coupling between acoustic modes and dynamic local ordering of the azetidium groups. Subsequent stiffening with further temperature reduction is interpreted in terms of classical strain–order parameter coupling at an improper ferroelastic transition which is close to being tricritical. By way of contrast, there are no overt changes in elastic or anelastic properties near 9 K, implying that any coupling of the antiferromagnetic order parameter with strain is weak or negligible.     

Carbon-13 cross-polarization magic-angle-spinning nuclear magnetic resonance investigation of the interactions between maleic anhydride grafted polypropylene and wood polymers

The chemical interactions between maleic anhydride grafted polypropylene (MAPP) and wood were studied with solid-state carbon-13 cross-polarization magic-angle-spinning nuclear magnetic resonance ((13)C CPMAS NMR) spectroscopy. MAPP was synthesized with 100% (13)C enrichment at the C(1) and C(4) carbons to allow detection of the [1,4-(13)C(2)]MAPP functional groups and was melt blended with cellulose, lignin, and maple wood. In the cellulose/MAPP blend, changes in (13)C CPMAS NMR corrected signal intensities for the anhydride and dicarboxylic maleic acid functionalities suggested that esterification may have occurred predominantly from the more numerous diacid carbons. A single proton longitudinal relaxation in the rotating frame, (H)T(1rho), for the MAPP and the cellulose carbons in the blend suggested that they were spin coupled, i.e., homogeneous on a 10-200 Angstrom scale. Esterification was also suggested in the lignin/MAPP blend. Furthermore, the more significant changes in the intensities of the carbonyl signals and (H)T(1rho) values suggested that lignin may be more reactive to MAPP than cellulose. Finally, when maple was melt blended with MAPP, the same trends in the (13)C CP-MAS NMR spectra and (H)T(1rho) behavior were observed as when MAPP was blended with cellulose or lignin. This study therefore clarifies that during melt compounding of wood with MAPP, esterification occurs with wood polymers, preferentially with lignin. Understanding the interactions of MAPP with wood is of significance for the development of natural-fiber-reinforced thermoplastic composites.     

Fate of Zinc Oxide Nanoparticles during Anaerobic Digestion of Wastewater and Post-Treatment Processing of Sewage Sludge

The rapid development and commercialization of nanomaterials will inevitably result in the release of nanoparticles (NPs) to the environment. As NPs often exhibit physical and chemical properties significantly different from those of their molecular or macrosize analogs, concern has been growing regarding their fate and toxicity in environmental compartments. The wastewater-sewage sludge pathway has been identified as a key release pathway leading to environmental exposure to NPs. In this study, we investigated the chemical transformation of two ZnO-NPs and one hydrophobic ZnO-NP commercial formulation (used in personal care products), during anaerobic digestion of wastewater. Changes in Zn speciation as a result of postprocessing of the sewage sludge, mimicking composting/stockpiling, were also assessed. The results indicated that "native" Zn and Zn added either as a soluble salt or as NPs was rapidly converted to sulfides in all treatments. The hydrophobicity of the commercial formulation retarded the conversion of ZnO-NP. However, at the end of the anaerobic digestion process and after postprocessing of the sewage sludge (which caused a significant change in Zn speciation), the speciation of Zn was similar across all treatments. This indicates that, at least for the material tested, the risk assessment of ZnO-NP through this exposure pathway can rely on the significant knowledge already available in regard to other "conventional" forms of Zn present in sewage sludge.     

Validation by a Collaborative Interlaboratory Study of an ELISA Method for the Detection of Caseinate Used as a Fining Agent in Wine

The clarification or fining of wine removes undesirable substances such as proteins, phenols, and tannin compounds that would cloud the wine and cause bitterness and astringency. Caseinates have useful fining properties, but their residues could present a risk for allergic subjects. A commercial kit that was developed to detect caseinates in food has been examined for its applicability to a wine matrix; it is sensitive to caseinates at concentrations as low as 1 ppm. The general characteristics of the caseinate assay, described below in detail, are as follows. It is a sandwich enzyme-linked immunosorbent assay (ELISA): the microplate is first coated with a specific anti-casein antibody; and after incubation with the wine sample, a secondary anti-casein antibody conjugated with horseradish peroxidase is added to form a sandwich. The antibodies have been tested for their immunoreactivity and the reproducibility of antigen recognition has been measured. An interlaboratory collaborative trial was organized to evaluate the performance of this ELISA method and its ease of use by laboratories routinely dealing with wine/food analyses. The results satisfy the criteria established by the International Organisation of Vine and Wine in the Compendium of International Methods of Analysis MA-EAS1-07-ETCOL.     

Using the Health Action Process Approach and implementation intentions to increase flu vaccine uptake in high risk Thai individuals: A controlled before-after trial.

Objective: Influenza vaccination rates remain suboptimal in many countries, including Thailand. This study compared the effect of a theory-based educational leaflet, based on the Health Action Process Approach (HAPA), and action planning intervention with a standard government information leaflet designed to increase influenza vaccination uptake among high-risk Thai adults. Design: A controlled before and after trial was conducted. Participants in the intervention (n = 99) received a leaflet based on the HAPA and asking them to form an action plan identifying where, when, and how they would seek vaccination. Those in the comparison condition (n = 102) received a standard government information leaflet. Main Outcomes Measures: There are 2 sets of outcome measures: (a) process measures of HAPA related variables taken at T1 and T2, and (b) vaccination rates during the subsequent 2 months. Results: The HAPA intervention resulted in greater changes on measures of risk perception, outcome expectancies, self-efficacy, and intention than the comparison condition. Stronger intentions to obtain vaccination were explained by changes in outcome expectancies, perceived self-efficacy for arranging time and transportation, and planning. No significant difference in vaccination rates was observed between two groups. Influenza vaccination was directly predicted by self-efficacy and intention. Conclusion: Results demonstrate that a HAPA-based leaflet may be a useful tool to enhance individual's vaccination intention, but larger trials are required to confirm these findings. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Effect of night smoking, sleep disturbance, and their co-occurrence on smoking outcomes.

Recent evidence suggests that smoking during the night is an indicator of nicotine dependence and predicts smoking cessation failure. Night smokers are likely to experience disturbance to their sleep cycle when they wake to smoke, but we are not aware of the prevalence of night smokers' self-reported sleep disturbance. Because sleep disturbance also predicts smoking cessation failure, we examined how the pre-cessation risk factors of night smoking and sleep disturbance, and their co-occurrence, predict smoking cessation failure in a 6-week double-blind randomized controlled trial examining whether naltrexone augments the efficacy of the nicotine patch (O'Malley et al., 2006). Smokers (N = 385) completed the Pittsburgh Sleep Quality Index (Buysse, Reynolds, Monk, Berman, & Kupfer, 1989) and a single item of waking at night to smoke pre-cessation. Smoking status was determined at weeks 1, 6, 24, and 48 weeks after quitting. The two main findings were: (a) night smokers reported significantly greater sleep disturbance than nonnight smokers; and (b) smokers with co-occurring night smoking and sleep disturbance experienced significantly greater risk for smoking than smokers with neither risk factor. Results suggest that individuals who both wake during the night to smoke and report clinically-significant sleep disturbance represent a high-risk group of smokers. Future smoking cessation treatment might incorporate strategies related to managing these smokers' sleep habits and physiological dependence on nicotine in order to bolster their cessation outcomes. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

NK Cells in Chronic Lymphocytic Leukemia and Their Therapeutic Implications

Key features of chronic lymphocytic leukemia (CLL) are defects in the immune system and the ability of leukemic cells to evade immune defenses and induce immunosuppression, resulting in increased susceptibility to infections and disease progression. Several immune effectors are impaired in CLL, including T and natural killer (NK) cells. The role of T cells in defense against CLL and in CLL progression and immunotherapy has been extensively studied. Less is known about the role of NK cells in this leukemia, and data on NK cell alterations in CLL are contrasting. Besides studies showing that NK cells have intrinsic defects in CLL, there is a large body of evidence indicating that NK cell dysfunctions in CLL mainly depend on the escape mechanisms employed by leukemic cells. In keeping, it has been shown that NK cell functions, including antibody-dependent cellular cytotoxicity (ADCC), can be retained and/or restored after adequate stimulation. Therefore, due to their preserved ADCC function and the reversibility of CLL-related dysfunctions, NK cells are an attractive source for novel immunotherapeutic strategies in this disease, including chimeric antigen receptor (CAR) therapy. Recently, satisfying clinical responses have been obtained in CLL patients using cord blood-derived CAR-NK cells, opening new possibilities for further exploring NK cells in the immunotherapy of CLL. However, notwithstanding the promising results of this clinical trial, more evidence is needed to fully understand whether and in which CLL cases NK cell-based immunotherapy may represent a valid, alternative/additional therapeutic option for this leukemia. In this review, we provide an overview of the current knowledge about phenotypic and functional alterations of NK cells in CLL and the mechanisms by which CLL cells circumvent NK cell-mediated immunosurveillance. Additionally, we discuss the potential relevance of using NK cells in CLL immunotherapy.     

Antioxidant Activity and Sensory Evaluation of a Rosmarinic Acid‐Enriched Extract of Salvia officinalis

An extract of Salvia officinalis (garden sage) was prepared using supercritical carbon dioxide (SC‐CO₂) extraction, followed by hot water extraction. The resulting extract was enriched in polyphenols, including rosmarinic acid (RA), which has shown promising health benefits in animals. The extract contained RA at a concentration of 28.4 mg/g, representing a significant enrichment from the RA content in sage leaves. This extract was incorporated into oil‐in‐water emulsions as a source of lipid antioxidants and compared to emulsions containing pure rosmarinic acid. Both treatments were effective in suppressing lipid oxidation. The extract was evaluated by a trained sensory panel in a tea formulation. While the panel could discriminate among extract‐treated and control samples, panelists demonstrated high acceptability of the sage extract in a tea.