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Context: The DNAN/DNB eutectic is a high-energy explosive eutectic with superior safety and thermal stability compared to traditional melt-cast explosives. However, the addition of polymer binders can effectively enhance its mechanical properties, allowing for continued production demands without the need for changes to existing factory equipment. In this paper, a model of the DNAN/DNB eutectic explosive was established, and five different types of polymers—cis-1,4-polybutadiene (BR), ethylene–vinyl acetate copolymer (EVA), polyethylene glycol (PEG), fluorinated polymer (F2603), and polyvinylidene fluoride (PVDF)—were added to the (1 0 − 1), (1 0 1), and (0 1 1) cleavage planes, respectively, to form polymer-bonded explosives (PBXs). The stability, trigger bond length, mechanical properties, and detonation performance of the various polymer-bound PBXs were predicted retrogressively. Among the five PBX models, the DNAN/DNB/PEG model exhibited the highest binding energy and the shortest trigger bond length, indicating a significant improvement in stability, compatibility, and sensitivity compared to the original eutectic. Additionally, although the detonation performance of DNAN/DNB decreased after the addition of binders, the final results were still satisfactory. Overall, the DNAN/DNB/PEG model demonstrated excellent comprehensive performance, proving that among the many polymer binders, PEG is the optimal choice for DNAN/DNB. Methods: Within the Materials Studio software, molecular dynamics (MD) simulations were employed to predict the properties of the DNAN/DNB eutectic PBX. The MD simulation timestep was set to 1 fs, with a cumulative simulation duration of 2 ns. A 2 ns MD simulation was conducted using the isothermal-isobaric ensemble (NPT). The COMPASS force field was applied, and the temperature was fixed at 295 K. [ABSTRACT FROM AUTHOR]

Bow wave breaking is a common phenomenon during ship navigation, especially at a high speed, involving complex physical mechanism such as interface mixing, air entrainment, and jet splashing. This study uses the delayed detached eddy simulation (DDES) turbulence model on the OpenFOAM platform to simulate flow around a KRISO Container Ship (KCS) model for a Froude number of 0.35, examining trim angles of 0°, 0.5°, 1°. This paper analyzes the statistical and power spectral density (PSD) characteristics of bow wave heights. The analysis shows root mean square (rms) and mean difference between top and bottom views indicate wave breaking. As the trim angle increases, peaks of rms in the bottom view become much higher than that in the top view, reaching 38% at 1°. PSD analysis reveals that resistance and wave height periods differ by no more than 5%, with small-scale structures like jetting and splashing causing non-dominant periodic and high-frequency wave height variations. [ABSTRACT FROM AUTHOR]

Understanding the intention of community residents to seek help from mental health professionals (MHPs) is essential in targeting interventions that promote the prevention and treatment of depression. This study aimed to investigate the current status of Chinese community populations' depression help-seeking intentions from MHPs and explore factors influencing the intentions. Data were used from a survey conducted in a city in central China (n = 919 aged 38.68 ± 17.34, 72.1% female). Help-seeking intentions, help-seeking attitude, depression stigma, family function and depressive symptoms were measured. The total mean score on the intent to seek help from MHPs was 11.01 ± 7.78 and most of respondents were unwilling to seek professional help. Multiple linear regression showed that participants who were students, held a positive help-seeking attitude and had low personal stigma were more likely to have the intention to seek help from MHPs. It is necessary to utilize effective interventions to improve community residents' intention to seek professional help. These include promoting the importance of seeking professional assistance, optimizing the quality of mental health services and altering residents' prejudice to seeking professional help. [ABSTRACT FROM AUTHOR]

Purpose: Human post mortem studies have described the topographical patterns of tau pathology in progressive supranuclear palsy (PSP). Recent advances in tau PET tracers are expected to herald the next era of PSP investigation for early detection of tau pathology in living brains. This study aimed to investigate whether 18F-Florzolotau PET imaging may capture the distribution patterns and regional vulnerability of tau pathology in PSP, and to devise a novel image-based staging system. Methods: The study cohort consisted of 148 consecutive patients with PSP who had undergone 18F-Florzolotau PET imaging. The PSP rating scale (PSPrs) was used to measure disease severity. Similarities and differences of tau deposition among different clinical phenotypes were examined at the regional and voxel levels. An 18F-Florzolotau pathological staging system was devised according to the scheme originally developed for post mortem data. In light of conditional probabilities for the sequence of events, an 18F-Florzolotau modified staging system by integrating clusters at the regional level was further developed. The ability of 18F-Florzolotau staging systems to reflect disease severity in terms of PSPrs score was assessed by analysis of variance. Results: The distribution patterns of 18F-Florzolotau accumulation in living brains of PSP showed a remarkable similarity to those reported in post mortem studies, with the binding intensity being markedly higher in Richardson's syndrome. Moreover, 18F-Florzolotau PET imaging allowed detecting regional vulnerability and tracking tau accumulation in an earlier fashion compared with post mortem immunostaining. The 18F-Florzolotau staging systems were positively correlated with clinical severity as reflected by PSPrs scores. Conclusions: 18F-Florzolotau PET imaging can effectively capture the distribution patterns and regional vulnerability of tau pathology in PSP. The 18F-Florzolotau modified staging system holds promise for early tracking of tau deposition in living brains. [ABSTRACT FROM AUTHOR]

Neurogenic sexual dysfunction (NSD) is a common problem in patients after spinal and pelvic trauma. New treatment is needed beyond medicine or psychological therapies. A 24-year-old man who fell from a six-floor building suffered from subsequent NSD. Repetitive transcranial magnetic stimulation (rTMS) was the only method used to treat his NSD caused by multiple spinal and pelvic injuries. The therapy lasted for 3 courses. Motor and sensory conduction, as well as sexual function, were evaluated before and after the rTMS intervention. Improvements on patient's nerve conduction and sexual activity were confirmed at a 1-year follow-up. Our findings indicate that rTMS delivered a novel, positive and low-cost modality treatment to the patient with NSD. Clinical efficacy and potential mechanisms by which rTMS regulate NSD need to be investigated by further clinical trials. [ABSTRACT FROM AUTHOR]

Background: The association between bone mineral density (BMD) and benign paroxysmal positional vertigo (BPPV) has been investigated by multiple studies, but the conclusions are controversial. This meta-analysis was conducted to evaluate whether the bone mineral density is associated with BPPV. Methods: The relevant studies were identified by searching PubMed, EMBASE, Cochrane Library, ScienceDirect, Web of Science database up to June 2018. Statas14.0 software was used for meta-analysis. We used the pooled odds ratio (OR) and 95% confidence interval (CI) to assess the incidence of osteoporosis and osteopenia in patients with BPPV and controls (free of BPPV disease). The standardized mean difference (SMD) and 95% confidence interval (CI) were used to assess the T score in BPPV patients and controls. This meta-analysis has been registered at International Prospective Register of Systematic Reviews (PROSPERO) (number CRD42018082271). Results: A total of 11 studies were eligible for meta-analysis, including 1982 subjects. When compared with the controls, the total incidence of osteoporosis and osteopenia was significantly higher in BPPV patients (OR 3.27, 95% CI 2.66–4.03, p < 0.0001). Further analysis was conducted by separate discussion about the incidence of osteoporosis and osteopenia in BPPV patients, the result of which shows that both the incidence of osteoporosis (OR 3.48, 95% CI 1.86–6.51, p < 0.0001) and the incidence of osteopenia (OR 1.75, 95% CI 1.01–3.04, p < 0.0001) were higher in BPPV patients than that in controls. There was an significant reduction in T scores of BPPV patients (SMD − 0.82, 95% CI −1.18 to − 0.46, p < 0.0001). Publication bias for each analysis was evaluated by Egger's test and Begg's indicating that no publication bias existed. Sensitivity analysis was conducted for each analysis demonstrating that the results were robust. Conclusions: Our meta-analysis provided stronger evidence that patients with BPPV were associated with a lower T score and a higher risk of osteoporosis and osteopenia. The results demonstrated that lower bone mineral density may be a risk factor for BPPV. However, large-scare, multicenter clinical studies need to be carried out to explore the precise risk of osteoporosis and osteopenia in patients with BPPV in future. [ABSTRACT FROM AUTHOR]

The chemical reaction between mold material and titanium melt during investment casting was studied intensively. However, the influence of residue gas in ceramic mold on interface reaction remains unclear. In this investigation, the effect of residue gas in Y2O3–silica sol shell mold on interface reaction during Ti–6Al–4V alloy investment casting was investigated. Two groups of shell molds were prepared by adding different kinds of pore formers, i.e., spherical starch particles or nylon fibers, respectively. Ti–6Al–4V alloy was cast under vacuum by gravity casting through cold crucible induction melting (CCIM) method. Porosity of different shell molds was measured based on Archimedean method. Scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) were employed to characterize the micromorphology and composition of the reaction area, respectively. White light interferometer (WLI) was used to obtain the surface topography of the shell mold. The results show that the direct chemical reaction is very weak for all specimens. The release of residue gas in closed pores is the key factor influencing surface defects. However, open pores make nearly no difference on the interface reaction. [ABSTRACT FROM AUTHOR]

Purpose: CXCL3 and its receptor CXCR2 were considered to play particularly important roles in the progression of malignancies. However, the investigations about CXCL3/CXCR2 axis in prostate cancer have been poorly involved. Herein we firstly reported our studies on the expression and biological roles of CXCL3 and CXCR2 in prostate cancer. Methods: Expression levels of CXCL3 and CXCR2 in prostate cancer cell lines (PC-3, DU145 and LNCaP), immortalized prostate stromal cell line (WPMY-1) and immortalized prostate epithelial cell line (RWPE-1) were investigated by RT-PCR, ELISA and western blot, whereas expression levels of CXCL3 in a prostate tissue microarray were detected by immunohistochemistry. Cell counting kit-8 and transwell assays were, respectively, utilized to determine the effects of exogenous CXCL3 on the cell proliferation and migration. We further examined whether CXCL3 could regulate the expression of genes correlated with prostate tumorigenesis by RT- PCR. Results: Elevated expression of CXCR2 was detected in DU145, LNCaP and RWPE-1. Moreover, high-level CXCL3 can be secreted by PC-3 and RWPE-1, and CXCL3 protein expression level in tissue microarray is concordant with prostate cancer metastasis. Exogenous CXCL3 does not contribute to proliferation, but has a significant effect on migration of prostate cancer cells and RWPE-1. Finally, our data showed that exogenous CXCL3 can regulate the expression of genes including ERK, TP73, NUMB, BAX and NDRG3. Conclusion: Our findings suggest that CXCL3 and its receptor CXCR2 are overexpressed in prostate cancer cells, prostate epithelial cells and prostate cancer tissues, which may play multiple roles in prostate cancer progression and metastasis. [ABSTRACT FROM AUTHOR]

Insulin- like growth factor 2 ( IGF2) is a potent cell growth and differentiation factor and is implicated in mammals' growth and development. The objective of this study was to evaluate the effects of the mutations in the bovine IGF2 with growth traits in Chinese Qinchuan cattle. Four single nucleotide polymorphisms (SNPs) were detected of the bovine IGF2 by DNA pool sequencing and forced polymerase chain reaction-restriction fragment length polymorphism (forced PCR-RFLP) methods. We also investigated haplotype structure and linkage disequilibrium (LD) coefficients for four SNPs in 817 individuals representing two main cattle breeds from China. The result of haplotype analysis showed eight different haplotypes and 27 combined genotypes within the study population. The statistical analyses indicated that the four SNPs, combined genotypes and haplotypes are associated with the withers height, body length, chest breadth, chest depth and body weight in Qinchuan cattle population ( P < 0.05 or <0.01). The mutant-type variants and mutant haplotype (Hap 8: ATGG; likely to be the beneficial QTN allele) was superior for growth traits; the heterozygote diplotype was associated with higher growth traits compared to wild-type homozygote. Our results provide evidence that polymorphisms in the IGF2 gene are associated with growth traits, and may be used for marker-assisted selection in beef cattle breeding program. [ABSTRACT FROM AUTHOR]

Octylphenol (OP) is the degradative product of alkylphenol ethoxylates that are widely used to produce rubber, pesticides, and paints. It is chemically stable substance and demonstrates estrogenic effects, toxicity and carcinogenic effects in the environment. The toxin accumulates rapidly in the liver where it exerts most of its damage, but the molecular mechanisms behind its toxicity remain unclear. Due to limited information concerning the effect of OP on liver, this study investigates how OP causes hepatotoxicity in liver. Here, suppression subtractive hybridization was used to identify the alterations in gene transcription of the frog ( Rana chensinensis) after exposure to OP. After hybridization and cloning, the subtractive cDNA libraries were obtained. At random, 207 positive clones were selected and sequenced from the subtractive libraries, which gave a total of 75 gene fragment sequences. The screening identified numerous genes involved in apoptosis, signal transduction, cytoskeletal remodeling, innate immunity, material and energy metabolism, translation and transcription which were extensively discussed. Two sequenced genes were analyzed further using real time quantitative PCR. The two genes from the library were found to be transcriptionally up-regulated. These results confirmed the successful construction of the subtractive cDNA library that was enriched for the genes that were differentially transcribed in the amphibian liver challenged with OP, and for the first time present the basic data on toxicity effect of OP on liver. [ABSTRACT FROM AUTHOR]

CuInSe thin films have been synthesized by selenization of co-sputtered Cu-In precursors using rapid thermal processing (RTP). Heat treatments from 400 to 450 °C for periods between 1 min and 10 min were carried out on (Cu-In)/Se precursors. Phase evolution as function of reaction temperature and holding time was analyzed according to XRD and SEM results. Severe Se loss during RTP was proved in our experiments and has been reported by many other researchers. To solve the problem, a new effective way of reducing Se loss was presented, which is based on low temperature heat treatment at 250 °C before high temperature annealing. Nearly single-phase CuInSe thin films have been achieved by annealing precursors at 250 °C for 5 min then 450 °C for 1 min. Se loss can be significantly reduced via low temperature heat treatment by the fact that under 250 °C, Se is evaporated mildly and largely consumed as Cu-Se and In-Se binary selenides. [ABSTRACT FROM AUTHOR]