The production of elemental sulfur from petroleum refining has created atechnological opportunity to increase the valorization of elemental sulfur by the creation of highperformance sulfur based plastics with improved thermomechanical properties,elasticity and flame retardancy.W ereport on asynthetic polymerization methodology to prepare the first example of sulfur based segmented multi-block polyurethanes (SPUs) and thermoplastic elastomers that incorporate an appreciable amount of sulfur into the final target material. This approach applied both the inverse vulcanization of S 8 with olefinic alcohols and dynamic covalent polymerizations with dienes to prepare sulfur polyols and terpolyols that were used in polymerizations with aromatic diisocyanates and short chain diols.Using these methods,anew class of high molecular weight, soluble blockcopolymer polyurethanes were prepared as confirmed by SizeE xclusion Chromatography,N MR spectroscopy, thermal analysis,a nd microscopic imaging. These sulfur-based polyurethanes were readily solution processed into large area free standing films where both the tensile strength and elasticity of these materials were controlled by variation of the sulfur polyol composition. SPUs with both high tensile strength (13-24 MPa) and ductility (348 %strain at break) were prepared, along with SPU thermoplastic elastomers (578 %s train at break) which are comparable values to classical thermoplastic polyurethanes (TPUs). The incorporation of sulfur into these polyurethanes enhanced flame retardancy in comparison to classical TPUs,w hich points to the opportunity to impart new properties to polymeric materials as ac onsequence of using elemental sulfur.
Mammalian spermatogenesis is a highly ordered process that occurs in mitotic, meiotic, and postmeiotic phases. The unique mechanisms responsible for this tightly regulated developmental process suggest the presence of an intrinsic genetic program composed of spermatogenic cell-specific genes. In this study, we analyzed the mouse round spermatid UniGene library currently containing 2124 gene-oriented transcript clusters, predicting that 467 of them are testis-specific genes, and systematically identified 28 novel genes with evident testis-specific expression by in silico and in vitro approaches. We analyzed these genes by Northern blot hybridization and cDNA cloning, demonstrating the presence of additional transcript sequences in five genes and multiple transcript isoforms in six genes. Genomic analysis revealed lack of human orthologues for 10 genes, implying a relationship between these genes and male reproduction unique to mouse. We found that all of the novel genes are expressed in developmentally regulated and stage-specific patterns, suggesting that they are primary regulators of male germ cell development. Using computational bioinformatics tools, we found that 20 gene products are potentially involved in various processes during spermatogenesis or fertilization. Taken together, we predict that over 20% of the genes from the round spermatid library are testis-specific, have discovered the 28 authentic, novel genes with probable spermatogenic cell-specific expression by the integrative approach, and provide new and thorough information about the novel genes by various in vitro and in silico analyses. Thus, the study establishes on a comprehensive scale a new basis for studies to uncover molecular mechanisms underlying the reproductive process.In sexual reproduction, diploid cells divide to form haploid cells, and the haploid cells from two individuals fertilize to form new diploid cells. This process, producing unpredictably dissimilar offspring, requires intricate and elaborate molecular and cellular events such as genetic recombination and the formation of gametes specialized for fertilization. Male germ cell development or spermatogenesis is a tightly regulated developmental process that occurs in successive mitotic, meiotic, and postmeiotic phases (1-3). The process occurs in the epithelial lining of seminiferous tubules, in testis. Spermatogonial stem cells, located around the outer region next to the basal lamina surrounding the seminiferous tubule, undergo mitosis, and some of them differentiate into later stage spermatogonia that gradually become primary spermatocytes. These cells continue through the first meiotic division to become secondary spermatocytes. Subsequently, the second meiotic division occurs in rapid succession to produce spermatids. These haploid spermatids are then remodeled into spermatozoa by spermiogenesis. The major events in spermiogenesis are chromatin condensation and morphological changes. This tightly regulated process accompanying meiotic progression and the drastic chang...
We propose an operational quasiprobability function for qudits, enabling a comparison between quantum and hidden-variable theories. We show that the quasiprobability function becomes positive semidefinite if consecutive measurement results are described by a hidden-variable model with locality and noninvasive measurability assumed. Otherwise, it is negative valued. The negativity depends on the observables to be measured as well as a given state, as the quasiprobability function is operationally defined. We also propose a marginal quasiprobability function and show that it plays the role of an entanglement witness for two qudits. In addition, we discuss an optical experiment of a polarization qubit to demonstrate its nonclassicality in terms of the quasiprobability function.Comment: 10 pages, 4 figures, journal versio
Optical Fourier surfaces (OFSs) are used for various applications, from diffractive optics to augmented reality (AR). However, the current methods of fabricating OFSs primarily rely on lithographic photochemical reactions and etching. These methods are likely to fabricate digitalized binary reliefs, which cannot match the ideal surface profile of OFSs. Such a profile is the sum of sinusoidal surfaces with various spatial frequencies. As an exception, scanning probe lithography (SPL) is found to be compatible with OFSs. However, the accessible pattern area of the OFSs created via SPL is relatively small owing to the serial feature of the fabrication, which in turn results in an undesired and complicated Fourier spectrum. In this article, the holographic inscription is redesigned for the low‐cost, large‐area, and rapid prototyping of customized OFSs. To this end, an integrative pipeline is established across numerical design, material optimization, and the pragmatic considerations of optical processing. Then, a soft molding strategy is suggested for optically transparent and flexible OFSs and its use for easy‐to‐craft AR devices. Overall, this intuitive framework not only expands the scope of Fourier optics but also acts as a field guide to azopolymeric OFSs and AR technology for experts and newcomers alike.
Many studies have explored the relationship between coffee—one of the most commonly consumed beverages today—and obesity. Despite inconsistent results, the relationship has not been systematically summarized. Thus, we conducted a meta-analysis by compiling data from 12 epidemiologic studies identified from PubMed and Embase through February 2019. The included studies assessed obesity by body mass index (BMI, a measure of overall adiposity) or waist circumference (WC, a measure of central adiposity); analyzed the measure as a continuous outcome or binary outcome. Using random effects model, weighted mean difference (WMD) and 95% confidence interval (CI) were obtained for continuous outcomes; summary relative risk (RR) and 95% CI for the highest vs. lowest categories of coffee intake were estimated for binary outcome. For BMI, WMD was −0.08 (95% CI −0.14, −0.02); RR was 1.49 (95% CI 0.97, 2.29). For WC, WMD was −0.27 (95% CI −0.51, −0.02) and RR was 1.07 (95% CI 0.84, 1.36). In subgroup analysis by sex, evidence for an inverse association was more evident in men, specifically for continuous outcome, with WMD −0.05 (95% CI −0.09, −0.02) for BMI and −0.21 (95% CI −0.35, −0.08) for WC. Our meta-analysis suggests that higher coffee intake might be modestly associated with reduced adiposity, particularly in men.
Worldwide, South Korea had the second highest incidence rates of colorectal cancer (CRC) in 2018. To inform public health policy to prevent CRC, we aimed to identify major modifiable lifestyle factors underlying the alarming increase in CRC incidence. We obtained information on CRC statistics from the Korea National Cancer Incidence Database and on the distribution of dietary and lifestyle factors known to modify CRC risk from the Korea National Health and Nutrition Examination Survey. To examine time trends between 2001 and 2013, we calculated annual percent changes of CRC incidence rates and of prevalence of etiologic factors by sex and age. Across all sex and age groups, the most commonly diagnosed cancer was rectal cancer while the most rapidly increasing cancer was distal colon cancer. For the lifestyle factors examined, decreases in exercise were observed across all age groups of both sexes. Yet, obesity and alcoholic drinks appear more relevant CRC contributor to men, smoking to women aged 30–49 years, and processed meat intake to adults aged 30–49 years. The heterogeneous results suggest that dietary and lifestyle target to prevent CRC be tailored by sex and age.
Alcohol is widely consumed and is known as a major risk factor for several types of cancers. Yet, it is unclear whether alcohol consumption is associated with the risk of prostate cancer (PCa) or not. We conducted linear and non-linear dose–response meta-analyses of cohort studies on alcohol consumption and PCa risk by types of alcohol (total, wine, beer, and liquor) and PCa (non-aggressive and aggressive). Pubmed and Embase were searched through April 2020 to identify relevant studies. Summary relative risk (RR) and 95% confidence interval (CI) were estimated using a random-effects model. For non-aggressive PCa, by alcohol type, the risk increased linearly with liquor (RR per 14 g/day intake (alcohol content in standard drink) being 1.04 (95% CI = 1.02–1.06, I2 = 0%, three studies) and non-linearly with beer (Pnon-linearity = 0.045, four studies), with increased risk observed in the lower range (RR = 1.03, 95% CI = 1.01–1.05; 14 g/day), with 1.05 (95% CI = 1.01–1.08) at 28 g/day. Wine was not significantly associated with the risk of non-aggressive PCa. For aggressive PCa, a non-linear relationship of diverse shapes was indicated for all types of alcohol in the sensitivity analysis. Compared to non-drinking, a significant positive association was more apparent at lower dose for liquor (RR = 1.12, 95% CI = 1.04–1.20 at 14 g/day; RR = 1.16, 95% CI = 1.03–1.31 at 28 g/day; Pnon-linearity = 0.005, three studies) but at higher doses for wine (RR = 1.02, 95% CI = 0.90–1.16 at 28 g/day, RR = 1.35, 95% CI = 1.08–1.67 at 56 g/day; Pnon-linearity = 0.01, four studies). In contrast, decreased risks were indicated at lower doses of beer (RR = 0.85, 95% CI = 0.79–0.92 at 14 g/day; RR = 0.79, 95% CI = 0.70–0.90 at 28 g/day, Pnon-linearity < 0.001, four studies). Total alcohol consumption was not associated with both types of PCa. In this study, we found heterogeneous associations between alcohol intake and PCa by types of alcohol and PCa.
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