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To study the effect of exposure mixture on the continuous health outcomes, one can use the linear model with a weighted sum of multiple standardized exposure variables as an index predictor and its coefficient for the overall effect. The unknown weights typically range between zero and one, indicating contributions of individual exposures to the overall effect. Because the weight parameters present only when the parameter for overall effect is non-zero, testing hypotheses on the overall effect can be challenging, especially when the number of exposure variables is above two. This paper presents a working model based approach to estimate the parameter for overall effect and to test specific hypotheses, including two tests for detecting the overall effect and one test for detecting unequal weights when the overall effect is evident. The statistics are computationally easy and one can apply existing statistical software to perform the analysis. A simulation study shows that the proposed estimators for the parameters of interest may have better finite sample performance than some other estimators. [ABSTRACT FROM AUTHOR]

Biorefinery of onion vinegar (OV) is attractive as a method for producing functional foods from onions or onion by-products. In this study, a two-stage fermentation of OV using Saccharomyces cerevisiae ATCC9763 and Acetobacter pasteurianus CICC20001 was carried out at 28 °C, the titratable acidity reached 4.01%, and the YA/E was 69.64% at 72 h. Based on this, semi-continuous fermentation was performed, proceeded to charge-discharge consisting of three cycles, and the yield, productivity, and specific production rate were 76.71%, 17.73 g/(L·d), and 20.51 h−1, respectively, which was higher than fed-batch fermentation. The in vivo antioxidant experiments showed that OV significantly increased GSH-Px, SOD, and CAT enzyme activities of Caenorhabditis elegans at 271.57, 129.26, and 314.68%, respectively. Nutritional analysis revealed that the total flavonoids and polyphenols were 3.01 mg/mL and 976.76 µg/mL, respectively. It was also shown that the acetic acid to total organic acid (A/T) ratio of OV was 79.02%, and the total free amino acid content was 262.30 mg/100 mL, 1.78–7.44 times higher than other fruit vinegar. The OV prepared in this study showed higher quality than the commercial vinegar. [ABSTRACT FROM AUTHOR]

In this study, intumescent flame retardant coating of polyethylenimine/phytic acid (PEI/PA) with gradient structure was constructed on cotton fabric through a facile layer-by-layer (LBL) assembly method. The LOI value of coated cotton fabric reached over 40%, indicating excellent flame retardancy. Reasonable controlling the LBL assembly process of PEI/PA coating brought less influence to the physical properties of cotton fabrics. And the coated cotton fabric revealed good flame retardant washing durability. Thermogravimetric analysis results of coated cotton fabrics showed that PEI/PA flame retardant coating changed the thermal decomposition process and promoted char formation revealing the obviously condensed phase flame retardant action. SEM images of char residues revealed that PEI/PA flame retardant coating promoted to form the intumescent flame retardant (IFR) char layer showing obvious IFR action. This research provides novel strategy for the development of high-efficiency flame retardant cotton fabric with good durability and physical properties using a simple LBL assembly method. [ABSTRACT FROM AUTHOR]

Nanozyme has been one of the most promising artificial enzymes for substitute natural enzymes. The main research focus in this field is developing the nanozymes with high activity, sensitivity and stability. In this paper, prussian blue/polyacrylonitrile (PB/PAN) composite nanofiber was prepared by electrospinning which was calcined to obtain iron oxide/carbon (FeOx/C) composite nanozyme. The structure of the prepared FeOx/C nanozyme was characterized by scanning electron microscopy (SEM), X-ray diffractometer (XRD), Energy dispersive spectrometer (EDS) and X-ray photoelectron spectra (XPS). The results revealed that FeOx/C nanozyme containing the catalytic active species of γ-Fe2O3 possessed peroxidase-like catalytic activity. The catalytic activity of prepared nanozyme which was influenced by different content of PB and different calcination temperatures was investigated. The optimal PB content in the PB/PAN nanofiber and calcination temperature were 41.5% and 600 °C in this research. The prepared FeOx/C nanozyme possessed highly sensitive detection of ascorbic acid. This research provides a new approach to fabricate iron oxide/carbon composite nanozyme with highly catalytic activity and sensitive for colorimetric sensor. [ABSTRACT FROM AUTHOR]

This study examined ecstasy use and associated risk and protective factors among Asian American youth. Data from 996 Asian American adolescents and 1,108 Asian American young adults were used. Ecstasy use was relatively common among Asian American youth. Among adolescents, it was associated with older age, poor parent-child communication, having been approached by drug sellers, living in a metropolitan area, and positive attitudes toward substance use. Among Asian American young adults, it was associated with having been born in the United States, having been approached by drug sellers, criminal justice system involvement, and positive attitudes toward substance use. Implications for designing substance use prevention/intervention programs for this minority group are discussed. [ABSTRACT FROM AUTHOR]

We demonstrate that 1,4-benzoxazines can be efficiently synthesized using 4-dimethylaminopyridine (DMAP) as a catalyst. We found that the DMAP catalyst can successfully promote the incorporation of the activated carbon atoms of α -halo ketones into the Schiff bases. The 1,4-benzoxazines can be synthesized through the formation of C–O and C–C bonds in high yield, using DMAP as the catalyst, α -halo ketones and phenolic Schiff bases as the reactants. Furthermore, a possible mechanism is proposed. This work provides a simple and efficient route to prepare the 1,4-benzoxazines. [ABSTRACT FROM AUTHOR]

Cu-Ni-Al–Fe-Mn alloy billets were prepared by heating–cooling combined mould (HCCM) continuous casting at different casting speeds. Then, the cold deformation behaviour of billets was studied by multi-pass cold rolling, and the effects of HCCM continuous casting on cold deformability were discussed by comparing with the mould casting (MC) alloy. The results show that HCCM continuous casting significantly improves the cold deformability of Cu-Ni-Al–Fe-Mn alloy billets. When the rolling reduction is 94%, HCCM continuous casting samples have good edge quality without obvious crack, while the MC sample has severe edge cracks. With the rolling reduction increasing from 40% to 94%, the elongation of the MC samples decreases from 6% to 2%, while that of HCCM continuous casting samples maintains in 6%∼9%, showing good continuous deformability. The HCCM continuous casting samples with lower casting speeds have [001] oriented columnar grains along the casting direction, which make the deformation mechanism change from nano-crystallization to parallel stacking faults. In the meanwhile, HCCM continuous casting improves deformation coordination of as-cast grains and restrains intergranular cracking, which is reflected in the influence on misorientation between as-cast grains and distribution of coarse NiAl phases. In addition, nano-twins found in the rolled MC sample promote the initiation and propagation of cracks. [ABSTRACT FROM AUTHOR]

We aimed to investigate oxidative stress biomarkers in a cross-sectional pilot study of 50 participants with sporadic ALS (SALS) compared to 46 control subjects. We measured urinary 8-oxodeoxyguanosine (8-oxodG), urinary 15-F2t-isoprostane (IsoP), and plasma protein carbonyl by ELISA methods. We also determined if ELISA measurement of 8-oxodG could be validated against measures from high-pressure liquid chromatography coupled with electrochemical detection, the current standard method. We found that 8-oxodG and IsoP levels adjusted for creatinine were significantly elevated in SALS participants. These differences persisted after age and gender were controlled in regression analyses. These markers are highly and positively correlated with each other. 8-oxodG measured by the two techniques from the same urine sample were positively correlated (p<.0001). Protein carbonyl was not different between SALS participants and controls. In conclusion, using ELISA, we confirmed that certain oxidative stress biomarkers were elevated in SALS participants. ELISA may be reliable and thus useful in epidemiology studies requiring large numbers of samples to determine the significance of increased oxidative stress markers in SALS. Further studies are required. [ABSTRACT FROM AUTHOR]

We report associations between serial measures of blood lead and intelligence in children age 10-12 years, half heavily exposed to lead from the prenatal period onward, and haft relatively unexposed. For a subsample, we examine bone lead-IQ associations, comparing them with bone lead associations. Both blood and bone lead levels were associated with intelligence decrements, small relative to the contribution of social factors. For each doubling of Tib-Pb, Full Scale, Performance, and Verbal IQ decreased by an estimated 5,5, 6.2. and 4.1 points, respectively. Bone lead-IQ associations were stronger than those for blood lead, which nonetheless provide robust analogues. Current BPb, easy to obtain, provides a useful means for assessing Pb exposure/IQ associations. [ABSTRACT FROM AUTHOR]

Unlabelled: Injecting drug users (IDUs) play a prominent role in the transmission of human immunodeficiency virus (HIV), particularly in urban areas such as New York City, where they comprise nearly half of all adult acquired immunodeficiency syndrome (AIDS) cases. Intervention studies have demonstrated that IDUs are responsive to safer sex messages, but sexual behavior appears to be more resistant to change than drug use behavior. This multidisciplinary study (without an intervention component) assesses changes in sexual risk behavior as a function of time, HIV status, and disease progression in a cohort of HIV+ and HIV- male IDUs (N = 144) for 4 years.Results: For HIV+ and HIV- men, there were increases in abstinence and monogamy, with decreases in the frequency of unprotected vaginal/anal sex and sexual risk index scores. With the exception of monogamy, HIV+ men reported lower levels of risk. Although there was also a decline in substance use, this accounted for only some of the decline in sexual risk behavior. Among the HIV+ men, a CD4 level below 200 was associated with more abstinence and monogamy. HIV-related medical symptoms were associated with increased abstinence, less unprotected sex, and lower sexual risk index scores. Lower neuropsychological memory test scores were associated with increased abstinence and lower sexual risk index scores. Neurological impairment and depression were not associated with sexual risk behavior.Conclusion: IDU men in New York City have modified their sexual behavior toward safer practices. Lower levels of risk are found among HIV+ men, particularly those with more progressed HIV illness. Nevertheless, a substantial amount of sexual risk behavior remained in this cohort, indicating the continued need for education and intervention. [ABSTRACT FROM AUTHOR]

Basis on molecular docking and pharmacophore analysis of naphthoquinone moiety, a total of 23 compounds were designed and synthesised. With the help of reverse targets searching, anti-cancer activity was preliminarily evaluated, most of them are effective against some tumour cells, especially compound 12: 1-(5,8-dihydroxy-1,4-dioxo-1,4-dihydronaphthalen-2-yl)-4-methylpent-3-en-1-yl-4-oxo-4-((4-phenoxyphenyl)amino) butanoate whose IC50 against SGC-7901 was 4.1 ± 2.6 μM. Meanwhile the anticancer mechanism of compound 12 had been investigated by AnnexinV/PI staining, immunofluorescence, Western blot assay and molecular docking. The results indicated that this compound might induce cell apoptosis and cell autophagy through regulating the PI3K signal pathway. [ABSTRACT FROM AUTHOR]

In this review, the system of multi-level collagen aggregates including collagen molecular, collagen fiber, advanced collagen aggregates, and tissues was reviewed. The preparation methods of multi-level collagen aggregates were introduced, and the relationship between structure and properties of them was analyzed and clarified. The general rule of structure-activity relationship of multi-level collagen aggregates under different modifiers and modified conditions was analyzed, and a theoretical basis for the application of multi-level collagen aggregates in biomedical field was provided. Finally, the applications of a series of biomedical materials of multi-level collagen aggregates and their modified products were listed. It is confirmed that the application field of multi-level collagen aggregates and their modified products might be far greater than collagen and other biomass. The multi-level collagen aggregates might have a very broad application prospect. [ABSTRACT FROM AUTHOR]

Three Ln(III)/K(I) (Ln = La, Ce and Nd) heterobismetal-capped cucurbit[5]uril molecular capsules, {[LaK(C30H30N20O10)Cl]Cl(H2O)3}Cl2·8H2O (1), {[CeK(C30H30N20O10)Cl]Cl(H2O)3}Cl4(H3O)22 + ·8H2O (2) and {[NdK(C30H30N20O10)Cl]Cl(H2O)3}Cl2·12.5H2O (3), were synthesised by self-assembly in aqueous solution, and their anion encapsulation property was confirmed by X-ray crystallography. The effect of the lanthanide cation radius on the structure of the heterobismetal-capped cucurbit[5]uril molecular capsules has been investigated. [ABSTRACT FROM AUTHOR]