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ObjectiveIn response to the problems of high weight and relatively low protective efficiency associated with traditional multicamerate structures (i.e., void compartment-liquid tank-void compartment), this study explores the protective performance of underwater cylindrical protective structures. Methods A numerical model based on an arbitrary Lagrangian-Eulerian (ALE) algorithm is established and verified through a contact explosion case involving a typical structure. On this basis, models of the traditional multicamerate protective structure and cylindrical protective structure are then established. Through numerical simulation, parameters such as maximal stress, strain and energy absorption after underwater contact explosion with the same explosive charge are analyzed, and their respective protective performances obtained.ResultsThe displacement of the defended longitudinal wall of the cylindrical protective structure is smaller than that of the watertight longitudinal wall, which is contrary to the behavior of traditional multicamerate protective structures. Additionally, the energy absorbed by the deck and double bottom is 9.92% less than that of the traditional protective structure, demonstrating a significant advantage in resisting deformation in the vertical direction.ConclusionThe results of this study indicate that the cylindrical protective structure exhibits a lower level of damage under the same charge, providing new insights for the innovative design of underwater protection structures.

This study aims to explore the molecular mechanisms of Lycium barbarum polysaccharide (LBP) in alleviating type 2 diabetes through intestinal flora modulation. A high-fat diet (HFD) combined with streptozotocin (STZ) was applied to create a diabetic model. The results indicated that LBP effectively alleviated the symptoms of hyperglycemia, hyperlipidemia, and insulin resistance in diabetic mice. A high dosage of LBP exerted better hypoglycemic effects than low and medium dosages. In diabetic mice, LBP significantly boosted the activities of CAT, SOD, and GSH-Px and reduced inflammation. The analysis of 16S rDNA disclosed that LBP notably improved the composition of intestinal flora, increasing the relative abundance of Bacteroides, Ruminococcaceae_UCG-014, Intestinimonas, Mucispirillum, Ruminococcaceae_UCG-009 and decreasing the relative abundance of Allobaculum, Dubosiella, Romboutsia. LBP significantly improved the production of short-chain fatty acids (SCFAs) in diabetic mice, which corresponded to the increase in the beneficial genus. According to Spearman’s correlation analysis, Cetobacterium, Streptococcus, Ralstonia. Cetobacterium, Ruminiclostridium, and Bifidobacterium correlated positively with insulin, whereas Cetobacterium, Millionella, Clostridium_sensu_stricto_1, Streptococcus, and Ruminococcaceae_UCG_009 correlated negatively with HOMA-IR, HDL-C, ALT, AST, TC, and lipopolysaccharide (LPS). These findings suggested that the mentioned genus may be beneficial to diabetic mice’s hypoglycemia and hypolipidemia. The up-regulation of peptide YY (PYY), glucagon-like peptide-1 (GLP-1), and insulin were remarkably reversed by LBP in diabetic mice. The real-time PCR (RT-PCR) analysis illustrated that LBP distinctly regulated the glucose metabolism of diabetic mice by activating the IRS/PI3K/Akt signal pathway. These results indicated that LBP effectively alleviated the hyperglycemia and hyperlipidemia of diabetic mice by modulating intestinal flora.

Abstract Background The influence of β-glucan on the human gut microbiota is closely related to the physicochemical structure of β-glucan. We purified a homogeneous water-soluble polysaccharide from Tibetan hull-less barley 25 and studied its structure and the in vitro fermentation profile. Results Analysis by gas chromatography (GC), Fourier-transformed infrared (FT-IR), nuclear magnetic resonance (NMR), scanning electron microscopy (SEM), and atomic force micrograph (AFM) helped determine the hull-less barley polysaccharide to be a β-glucan (molecular weight: 3.45 × 104 Da), which was further characterized as mixed-linkage (1 → 3)(1 → 4)-linked β-d-glucans. SEM images demonstrated an intricate web structure of the hull-less barley polysaccharide, while the AFM images revealed the presence of small spherical particles in its structure. In addition, the microbiota composition of the hull-less barley polysaccharide group was found to be altered, wherein the abundance of Pantoea, Megamonas, Bifidobacterium, and Prevotella-9 were increased. On the other hand, in vitro fermentation revealed that hull-less barley polysaccharide significantly decreased the pH value and increased the production of acetate, propionate, and butyrate. Conclusions Hull-less barley polysaccharide is a type of dietary fiber, and its analysis suggested that it may serve as a prebiotic food supplement for the regulation of the gut microbiota.

State-of-the-art next-generation sequencing (NGS)-based subclonal reconstruction methods perform poorly on somatic copy number alternations (SCNAs), due to not only it needs to simultaneously estimate the subclonal population frequency and the absolute copy number for each SCNA, but also there exist complex bias and noise in the tumor and its paired normal sequencing data. Both existing NGS-based SCNA detection methods and SCNA’s subclonal population frequency inferring tools use the read count on radio (RCR) of tumor to its paired normal as the key feature of tumor sequencing data; however, the sequencing error and bias have great impact on RCR, which leads to a large number of redundant SCNA segments that make the subsequent process of SCNA’s subclonal population frequency inferring and subclonal reconstruction time-consuming and inaccurate. We perform a mathematical analysis of the solution number of SCNA’s subclonal frequency, and we propose a computational algorithm to reduce the impact of false breakpoints based on it. We construct a new probability model that incorporates the RCR bias correction algorithm, and by stringing it with the false breakpoint filtering algorithm, we construct a whole SCNA’s subclonal population reconstruction pipeline. The experimental result shows that our pipeline outperforms the existing subclonal reconstruction programs both on simulated data and TCGA data. Source code is publicly available as a Python package at https://github.com/dustincys/msphy-SCNAClonal.

Circular RNAs (circRNAs) are a novel class of endogenous noncoding RNAs that have well-conserved sequences. Emerging evidence has shown that circRNAs can be novel biomarkers or therapeutic targets for many diseases and play an important role in the development of various pathological conditions. Therefore, identifying potential disease-related circRNAs is helpful in improving the efficiency of finding therapeutic targets for diseases. Here, we propose a computational model (PreCDA) to predict potential circRNA–disease associations. First, we calculated the circRNA expression similarity based on circRNA expression profiles. The circRNA functional similarity is calculated based on cosine similarity, and the disease similarity is used as the dimension of each circRNA vector. The associations between circRNAs and diseases are defined based on the circRNA functional similarity and expression similarity. We constructed a disease-related circRNA association network and used a graph-based recommendation algorithm (PersonalRank) to sort candidate disease-related circRNAs. As a result, PreCDA has an average area under the receiver operating characteristic curve value of 78.15% in predicting candidate disease-related circRNAs. In addition, we discuss the factors that affect the performance of this method and find some unknown circRNAs related to diseases, with several common diseases used as case studies. These results show that PreCDA has good performance in predicting potential circRNA–disease associations and is helpful for the diagnosis and treatment of human diseases.

Background: Since the first HIV-1 case in 1989, Hebei province has presented a clearly rising trend of HIV-1 prevalence, and HIV-1 genetic diversity has become the vital barrier to HIV prevention and control in this area. To obtain detailed information of HIV-1 spread in different populations and in different areas of Hebei, a cross-sectional HIV-1 molecular epidemiological investigation was performed across the province. Methods: Blood samples of 154 newly diagnosed HIV-1 individuals were collected from ten prefectures in Hebei using stratified sampling. Partial gag and env genes were amplified and sequenced. HIV-1 genotypes were identified by phylogenetic tree analyses. Results: Among the 139 subjects genotyped, six HIV-1 subtypes were identified successfully, including subtype B (41.0 %), CRF01_AE (40.3 %), CRF07_BC (11.5 %), CRF08_BC (4.3 %), unique recombinant forms (URFs) (1.4 %) and subtype C (1.4 %). Subtype B was identified as the most frequent subtype. Two URF recombination patterns were the same as CRF01_AE/B. HIV-1 genotype distribution showed a significant statistical difference in different demographic characteristics, such as source (P < 0.05), occupation (P < 0.05) and ethnicity (P < 0.05). The distributions of subtype B (P < 0.05), CRF01_AE (P < 0.05), CRF07_BC (P < 0.05) and subtype C (P < 0.05) showed significant differences in all ten prefectures, and the distributions of all six subtypes were significantly different in Shijiazhuang (P < 0.05) and Xingtai (P < 0.05), but not in other prefectures (P > 0.05). The differences in HIV-1 genotype distribution were closely associated with transmission routes. Particularly, all six subtype strains were found in heterosexuals, showing that HIV-1 has spread from the high-risk populations to the general populations in Hebei, China. In addition, CRF01_AE instead of subtype B has become the major strain of HIV-1 infection among homosexuals. Conclusions: Our study revealed HIV-1 evolution and genotype distribution by investigating newly diagnosed HIV-1 individuals in Hebei, China. This study provides important information to enhance the strategic plan for HIV prevention and control in China. [ABSTRACT FROM AUTHOR]