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Abstract Oxidative damage to human retinal pigment epithelial (RPE) cells is the main cause of age-related macular degeneration (AMD), in our previous work, we showed that ghrelin has an antioxidative effect on human lens epithelium (HLE) cells, however, the studies of using ghrelin in treating the degenerative diseases of the retina have rarely been reported. In this article, we assessed the effect of ghrelin on preventing oxidative stress induced by hydrogen peroxide (H2O2) in ARPE-19 cells and its mechanism. We observed that pretreatment with ghrelin protected ARPE-19 cells from H2O2-induced cell oxidative injuries and apoptosis responses. Furthermore, an oxidative stress-induced mouse model of AMD was established via injection of sodium iodate (NaIO3) to tail veins, and treatment with ghrelin preserved retinal function, and protected photoreceptors.

Abstract Revealing the heterogeneity among tissues is the greatest advantage of single-cell-sequencing. Marker genes not only act as the key to correctly identify cell types, but also the bio-markers for cell-status under certain experimental imputations. Current analysis methods such as Seurat and Monocle employ algorithms which compares one cluster to all the rest and select markers according to statistical tests. This pattern brings redundant calculations and thus, results in low calculation efficiency, specificity and accuracy. To address these issues, we introduce starTracer, a novel algorithm designed to enhance the efficiency, specificity and accuracy of marker gene identification in single-cell RNA-seq data analysis. starTracer operates as an independent pipeline, which exhibits great flexibility by accepting multiple input file types. The primary output is a marker matrix, where genes are sorted by the potential to function as markers, with those exhibiting the greatest potential positioned at the top. The speed improvement ranges by 2 ~ 3 orders of magnitude compared to Seurat, as observed across three independent datasets with lower false positive rate as observed in a simulated testing dataset with ground-truth. It’s worth noting that starTracer exhibits increasing speed improvement with larger data volumes. It also excels in identifying markers in smaller clusters. These advantages solidify starTracer as an important tool for single-cell RNA-seq data, merging robust accuracy with exceptional speed.

AbstractThe brown-eared bulbul (Hypsipetes amaurotis) is a medium-sized songbird native to East Asia and characterized by its prominent reddish-brown ear-coverts. Previous studies on it have primarily been from the taxonomic and morphological aspects, with limited research in the realm of molecular biology. In this study, we sequenced and annotated the complete mitochondrial genome of H. amaurotis, which was the first reported complete mitogenome of the genus Hypsipetes. The mitogenome of H. amaurotis is 17,871 bp in length and was predicted to encode 37 typical mitochondrial genes, including 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), two ribosomal RNA genes (rRNAs). Specifically, this mitogenome contains two D-loop control regions that are of similar length and sequencing pattern. A total of 8 Pycnonotidae and six outgroup taxa were used to determine the phylogenetic placement with two methods: Maximum Likelihood Approximation (IQ-TREE) and Bayesian inference (MrBayes). Our findings reveal that H. amaurotis is phylogenetically closely related to Ixos mcclellandii. The outcomes are generally consistent with the phylogenetic trees constructed in previous studies. The data gathered from this research provides valuable insights for future genomic investigations into the evolution, ecology, and conservation of this species.

Abstract Background With the increasing number of bariatric surgeries, the high incidence of postoperative nausea and vomiting (PONV) associated with this surgery has also gradually attracted attention. Among the common bariatric surgery methods, patients undergoing sleeve gastrectomy (SG) have the highest incidence of nausea and vomiting. The mechanism of occurrence of PONV is very complex. This study aims to explore the influencing factors of PONV in patients undergoing laparoscopic sleeve gastrectomy (LSG) and construct a nomogram prediction model based on these factors. Methods With the approval of the Ethics Committee, the electronic medical records of patients who underwent LSG from July 2022 to May 2023 were collected retrospectively. Results A total of 114 patients with complete medical records who underwent LSG from July 2022 to May 2023 were included in this study. Among them, 46 patients developed PONV, resulting in a PONV incidence rate of 40.4%. Multivariate logistic regression analysis revealed that female gender, the use of inhalation anesthesia, and operation time ≥ 120 min were risk factors for PONV in LSG. Additionally, the use of more than two kinds of antiemetic drugs was identified as a protective factor. Based on these factors, a nomogram model was constructed. Conclusion PONV in patients undergoing LSG is related to gender, type of anesthesia, duration of surgery, and combination therapy with antiemetic drugs. The nomogram prediction model constructed in this study demonstrates high accuracy and discrimination in predicting the occurrence of PONV in patients undergoing LSG.

Abstract Background Bladder urothelial carcinoma (BLCA) is the most common genitourinary cancer and the prognosis of patients is often poor. However, studies of basement membrane-related genes (BM-related genes) in BLCA are less reported. Therefore, we established a BM-related genes signature to explore their functional and prognostic value in BLCA. Methods In this study, a BM-related genes signature was constructed by LASSO-Cox regression analysis, and then a series of bioinformatics methods was used to assess the accuracy and validity of the signature. We constructed a nomogram for clinical application and also screened for possible therapeutic drugs. To investigate the functions and pathways affected by BM-related genes in BLCA, we performed functional enrichment analyses. In addition, we analyzed the immune cell infiltration landscape and immune checkpoint-related genes in the high and low-risk groups. Finally, we confirmed the prognostic value of BM-related genes in BLCA in vitro. Results Combining multiple bioinformatics approaches, we identified a seven-gene signature. The accuracy and validity of this signature in predicting BLCA patients were confirmed by the test cohort. In addition, the risk score was strongly correlated with prognosis, immune checkpoint genes, drug sensitivity, and immune cell infiltration landscape. The risk score is an independent prognostic factor for BLCA patients. Further experiments revealed that all seven signature genes were differentially expressed between BLCA cell lines and normal bladder cells. Finally, overexpression of LAMA2 inhibited the migration and invasion ability of BLCA cell lines. Conclusions In summary, the BM-related genes signature was able to predict the prognosis of BLCA patients accurately, indicating that the BM-related genes possess great clinical value in the diagnosis and treatment of BLCA. Moreover, LAMA2 could be a potential therapeutic target, which provides new insights into the application of the BM-related genes in BLCA patients.

Abstract Cardiac myxoma (CM) is the most common benign cardiac tumor, and most CMs are left atrial myxomas (LAMs). Six variations of KIF1C, c.899 A > T, c.772 T > G, c.352 A > T, c.2895 C > T, c.3049 G > A, and c.*442_*443dup in left atrial myxoma tissues are identified by whole-exome sequencing (WES) and Sanger sequencing. RNA-seq and function experiments show the reduction of the expression of KIF1C and PRKAR1A caused by rare variations of KIF1C. KIF1C is observed to be located in the nucleus, bind to the promoter region of PRKAR1A, and regulate its transcription. Reduction of KIF1C decreases PRKAR1A expression and activates the PKA, which causes an increase in ERK1/2 phosphorylation and SRC-mediated STAT3 activation, a reduction of CDH1, TP53, CDKN1A, and BAX, and eventually promotes tumor formation both in vitro and in vivo. The results suggest that inhibition of KIF1C promotes the pathogenesis of LAM through positive feedback formed by the crosstalk between KIF1C and PRKAR1A.

On the basis of the conjugate gradient method, an inversion model of the transient convective heat transfer coefficient between the bore surface and the gunpowder gas is presented. In this study, the measured temperature at a certain depth from the bore surface is employed as input. The variation of the thermophysical properties of gun steel with respect to temperature is taken into consideration. After verifying the feasibility of the model with constant convective heat transfer coefficients, it is applied to the reconstruction of transient convective heat transfer coefficients that consistent with the classical interior ballistic laws. Results indicate that decreasing the measurement error and increasing the number of measurement points can effectively improve the performance of the model. As well, measurement points that placed further away from the inlet boundary offer superior accuracy. When studying the inverse heat transfer problem of the gun barrel, it is found that setting the monitoring time to be twice the duration of the interior ballistic period may guarantee sufficient input data. The inversion model may offer a promising theoretical framework for indirect measurement manner of the bore surface temperature of gun barrel.

A 2-D inversion model to reconstruct the transient inner wall heat flux of the coated barrel is proposed in this paper. Indirect measurement of the inner wall temperature of the barrel under harsh conditions is realized. Measurement points locate at specified distances from the inner surface. Temperature calculated from a direct problem plus the measurement errors is taken as measured temperature. Variations of the temperature dependent thermo-physical properties of materials are taken into consideration. The total heat input of the firing and thermal resistance between chromium coating and gun steel are determined by depths of gun steel phase transition and chromium recrystallization after firing. The direct problem, sensitivity problem and adjoint problem are solved with the finite difference method (FDM). After verifying the reliability of the inversion model with a special numerical example, it is promoted to reconstruction of general heat flux varying with time and space. Results indicate that decreasing the measurement error and increasing the number of measurement points can effectively improve the performance of the model. As well, measurement points closer to the inner wall offer superior accuracy. The inversion model herein can serve as a promising indirect measurement method of the inner wall temperature.

Disulfidptosis is a newly discovered mode of cell death induced by disulfide stress. However, the prognostic value of disulfidptosis-related genes (DRGs) in renal cell carcinoma (RCC) remains to be further elucidated. In this study, consistent cluster analysis was used to classify 571 RCC samples into three DRG-related subtypes based on changes in DRGs expression. Through univariate regression analysis and LASSO-Cox regression analysis of differentially expressed genes (DEGs) among three subtypes, we constructed and validated a DRG risk score to predict the prognosis of patients with RCC, while also identifying three gene subtypes. Analysis of DRG risk score, clinical characteristics, tumor microenvironment (TME), somatic cell mutations, and immunotherapy sensitivity revealed significant correlations between them. A series of studies have shown that MSH3 can be a potential biomarker of RCC, and its low expression is associated with poor prognosis in patients with RCC. Last but not least, overexpression of MSH3 promotes cell death in two RCC cell lines under glucose starvation conditions, indicating that MSH3 is a key gene in the process of cell disulfidptosis. In summary, we identify potential mechanism of RCC progression through DRGs -related tumor microenvironment remodeling. In addition, this study has successfully established a new disulfidptosis-related genes prediction model and discovered a key gene MSH3. They may be new prognostic biomarkers for RCC patients, provide new insights for the treatment of RCC patients, and may inspire new methods for the diagnosis and treatment of RCC patients.

Summary: Vigorous-intensity leisure-time physical activity, such as marathon, has become increasingly popular, but its effect on immune functions and health is poorly understood. Here, we performed scRNA-seq analysis of peripheral blood mononuclear cells (PBMCs) after a bout of symptom-limited cardiopulmonary exercise (CPX) test or marathon. Time-series single-cell analysis revealed the detailed series of landscapes of immune cells in response to short and long vigorous-intensity activities. Reduction of effective T cells was observed with the cell migration and motility pathways enriched in circulation following marathon. Baseline values of PBMCs abundance were reached around 1 h after CPX and 24 h following marathon, but longer time was required for expression recovery of cytotoxicity genes. The ratio of effector/naive T cells was found to change uniformly among the participants and could serve as a better indicator for exercise intensity than the CD4+/CD8+ T cell ratio. Moreover, we identified time-dependent monocyte state transitions after marathon.

Fecal microbiota transplantation (FMT) of human fecal samples into germ-free (GF) mice is useful for establishing causal relationships between the gut microbiota and human phenotypes. However, due to the intrinsic differences between human and mouse intestines and the different diets of the two organisms, it may not be possible to replicate human phenotypes in mice through FMT; similarly, treatments that are effective in mouse models may not be effective in humans. In this study, we aimed to identify human gut microbes that undergo significant and consistent changes (i.e., in relative abundances) after transplantation into GF mice in multiple experimental settings. We collected 16S rDNA-seq data from four published studies and analyzed the gut microbiota profiles from 1713 human–mouse pairs. Strikingly, on average, we found that only 47% of the human gut microbes could be re-established in mice at the species level, among which more than 1/3 underwent significant changes (referred to as “variable taxa”). Most of the human gut microbes that underwent significant changes were consistent across multiple human–mouse pairs and experimental settings. Consequently, about 1/3 of human samples changed their enterotypes, i.e., significant changes in their leading species after FMT. Mice fed with a controlled diet showed a lower enterotype change rate (23.5%) than those fed with a noncontrolled diet (49.0%), suggesting a possible solution for rescue. Most of the variable taxa have been reported to be implicated in human diseases, with some recognized as the causative species. Our results highlight the challenges of using a mouse model to replicate human gut microbiota-associated phenotypes, provide useful information for researchers using mice in gut microbiota studies, and call for additional validations after FMT. An online database named FMT-DB is publicly available at http://fmt2mice.humangut.info/#/.

Background: Prostate cancer (PC) is one of the most commonly diagnosed cancer in men worldwide. Epithelial-mesenchymal transition (EMT) is considered to play a crucial role in the development of the metastatic castration-resistant prostate cancer, which causes the majority of the death cases in PC. Golgi membrane protein 1 (GOLM1) is highly expressed in PC and has been identified as a driver factor for EMT in various cancers. However, its biological functions and underlying mechanisms remain ambiguous in PC. Method: GOLM1 expression level of PC was detected by Western blot and immunohistochemistry analyses. To investigate GOLM1 functions in cancer cells, we overexpressed and knocked down GOLM1 in different prostate cancer cell lines. Transwell assay and wound healing assay were used to determine the role of GOLM1 in cell EMT, such as migration and invasion abilities. TGF-β1/Smad2 signaling pathway downstream of GOLM1 was detected by Western blot and Transwell assay. Result: GOLM1 expression is up-regulated in PC and correlated with a worse prognosis. GOLM1 promotes the abilities of migration and invasion in PC cell lines (DU145 and LNCaP). Furthermore, TGF-β1/Smad2 signaling is positively regulated by GOLM1 to facilitate EMT in PC, whereas this role can be restored by TGF-β1 after GOLM1 knockdown or be abrogated by p-Smad inhibitor SB431542. Conclusion: GOLM1 is significantly upregulated in PC and acts as a critical oncogene by promoting PC cell EMT process by activating TGF-β1/Smad2 signaling pathway. Therefore, GOLM1 has the potential to be a biomarker for PC diagnosis and to predict the prognosis of PC patients. It is of great significance to seek effective and specific inhibitor of GOLM1 for PC treatment as well.

Abstract Premature ovarian insufficiency (POI) is a heterogeneous and multifactorial disorder. In recent years, there has been an increasing interest in research on the pathogenesis and treatment of POI, owing to the implementation of the second-child policy in China. Cytoplasmic polyadenylation element-binding protein 3 (CPEB3) is an RNA-binding protein that can bind to specific RNA sequences. CPEB3 can bind to and affect the expression, cellular location, and stability of target RNAs. Cpeb3 is highly expressed in the ovary; however, its functions remain unknown. In this study, Cpeb3-mutant mice were used to characterize the physiological functions of CPEB3. Cpeb3-mutant female mice manifested signs of gradual loss of ovarian follicles, ovarian follicle development arrest, increased follicle atresia, and subfertility with a phenotype analogous to POI in women. Further analysis showed that granulosa cell proliferation was inhibited and apoptosis was markedly increased in Cpeb3-mutant ovaries. In addition, the expression of Gdf9, a potential target of CPEB3, was decreased in Cpeb3-mutant ovaries and oocytes. Altogether, these results reveal that CPEB3 is essential for ovarian follicle development and female fertility as it regulates the expression of Gdf9 in oocytes, disruption of which leads to impaired ovarian follicle development and POI.

Necroptosis is a type of caspase-independent cell death, and it plays a critical role in regulating the development of cancer. To date, little is known about the role of necroptosis-related genes (NRGs) in clear cell renal cell carcinoma (ccRCC). In this study, we downloaded data regarding the expression of NRGs and overall survival (OS) from The Cancer Genome Atlas (TCGA) database and constructed a risk model to determine the prognostic features of necroptosis using COX regression analysis. Patients with ccRCC were divided into low-risk and high-risk groups based on their risk scores. Thereafter, Kaplan–Meier curves were used to evaluate OS, and receiver operating characteristic (ROC) curves were used to determine the accuracy of prediction. Stratified analyses were performed according to different clinical variables. Furthermore, we assessed the correlation between clinical variables and risk scores; the NRGs with differential expression were mainly enriched in positive regulation of intracellular transport and platinum resistance pathways. We constructed prognostic signatures for OS based on four NRGs and showed that the survival time was significantly longer in the low-risk groups than in the high-risk groups (p < 0.001). The area of the ROC curve for OS was 0.717, indicating excellent predictive accuracy of the established model. Therefore, a predictive model based on NRGs was constructed, which can predict the prognosis of patients and provides insights into the biological mechanisms underlying necroptosis in patients with ccRCC.

The mechanisms of acute kidney injury and chronic kidney disease remain incompletely revealed, and drug development is a pressing clinical challenge. Oxidative stress-induced cellular senescence and mitochondrial damage are important biological events in a variety of kidney diseases. As a type of carotenoid, β-Cryptoxanthin (BCX) has various biological functions, which means it is a potential therapeutic candidate for the treatment of kidney disease. However, the role of BCX in the kidney is unclear, and the effect of BCX on oxidative stress and cellular senescence in renal cells is also unknown. Therefore, we conducted a series of studies on human renal tubular epithelial (HK-2) cells in vitro. In the present study, we investigated the effect of BCX pretreatment on H2O2-induced oxidative stress and cellular senescence and explored the potential mechanism of BCX action. The results showed that BCX attenuated H2O2-induced oxidative stress and cellular senescence in HK-2 cells. Moreover, BCX promoted NRF2 nuclear expression, maintained mitochondrial function, and reduced mitochondrial damage in HK-2 cells. In addition, silencing NRF2 altered the protective effect of BCX on mitochondria and significantly reversed the anti-oxidative stress and anti-senescence effects of BCX in HK-2 cells. We concluded that BCX maintained mitochondrial function by promoting NRF2 nuclear translocation to inhibit oxidative stress-induced senescence in HK-2 cells. In light of these findings, the application of BCX might be a promising strategy for the prevention and treatment of kidney diseases.

Pathway-level analysis is a powerful approach enabling the interpretation of post-genomic data at a higher level than that of individual molecules. Molecular-targeted therapy focusing on cascade signaling pathways has become a new paradigm in anticancer therapy, instead of a single protein. However, the approaches to narrowing down the long list of biological pathways are limited. Here, we proposed a strategy for in silico Drug Prescription on biological pathways across pan-Cancers (CDP), by connecting drugs to candidate pathways. Applying on a list of 120 traditional Chinese medicines (TCM), we especially identified the “TCM–pathways–cancers” triplet and constructed it into a heterogeneous network across pan-cancers. Applying them into TCMs, the computational prescribing methods deepened the understanding of the efficacy of TCM at the molecular level. Further applying them into Western medicines, CDP could promote drug reposition avoiding time-consuming developments of new drugs.

Abstract Purpose: To investigate the effect of Picroside II on testicular ischemia and reperfusion (l/R) injury and the underlying mechanism. Methods: Sprague-Dawley rats were randomly divided into 4 groups: sham operated group (Sham), Sham with Picroside II treatment group (Sham+ Pic II), l/R group (l/R) and l/R with Picroside II treatment group (I/R+ Pic II). l/R model was established by rotating the left testis 720° in a clock-wise direction for 4 hours. The histopathologic and spermatogenetic evaluation was performed. The apoptosis changes and the levels of HO-1 (heme oxygenase-1), MPO (myeloperoxidase), NOX (NADPH oxidase), SOD (superoxide dismutase), XO (xanthine oxidase) and NOS (nitric oxide synthase) were measured. Results: The seminiferous tubules were damaged in l/R rats, but Picroside II alleviated the changes induced by l/R. The increased level of apoptosis was decreased by Picroside II (P=0.01, 9.05±0.35 vs. 4.85±0.25). The activities of HO-1, MPO, NOX, XO and MDA content were increased and the SOD activity was decreased in l/R (P

Glass is one of the materials most extensively used for packaging. Its manufacturing process is typically energy intensive, with a large quantity of CO2 emissions. In this study, the material and energy consumptioninventory of the manufacturing stage were quantified and CO2 emissions from the glass manufacturing process were calculated. When fuel oil, coal or natural gas is used as the major energy source in the production system, it produces CO2 emissions of 1.2798, 0.6250 and 0.4498 t/t, respectively. CO2 emissions from fossil fuel combustion account for 67.79% of the total emissions and a huge potential exists for emission reduction. Due to differences in energy structure, current research results cannot represent the emissions in China; therefore, six scenarios were created to explore the CO2 emission reduction potential of the glass industry with different energy structures, and six scenarios were created to explore the cost from the adjustment of the energy structure. According to the analysis of the glass furnace, the effective heat accounts for 35.31%, so the basic approach for energy saving and emission reduction is to enhance the effective heat quantity of the glass furnace. Also, energy and virgin feedstock savings were calculated for 1 t of glass container production with different recycling levels.

Background/Aims: Diabetes mellitus (DM) has been demonstrated to have a strong association with heart failure. Conventional echocardiographic analysis cannot sensitively monitor cardiac dysfunction in type I diabetic Akita hearts, but the phenotype of heart failure is observed in molecular levels during the early stages. Methods: Male Akita (Ins2WT/C96Y) mice were monitored with echocardiographic imaging at various ages, and then with conventional echocardiographic analysis and speckle-tracking based strain analyses. Results: With speckle-tracking based strain analyses, diabetic Akita mice showed changes in average global radial strain at the age of 12 weeks, as well as decreased longitudinal strain. These changes occurred in the early stage and remained throughout the progression of diabetic cardiomyopathy in Akita mice. Speckle-tracking showed that the detailed and precise changes of cardiac deformation in the progression of diabetic cardiomyopathy in the genetic type I diabetic Akita mice were uncoupled. Conclusions: We monitored early-stage changes in the heart of diabetic Akita mice. We utilize this technique to elucidate the underlying mechanism for heart failure in Akita genetic type I diabetic mice. It will further advance the assessment of cardiac abnormalities, as well as the discovery of new drug treatments using Akita genetic type I diabetic mice.

Abstract Cell death inducing DNA fragmentation factor-alpha-like A (Cidea) is a member of cell death-inducing DFF45-like effector (CIDE) protein. The initial function of CIDE is the promotion of cell death and DNA fragmentation in mammalian cells. Cidea was recently reported to play critical roles in the development of hepatic steatosis. The purpose of present study is to determine the effect of chronic alcohol intake on Cidea expression in the livers of mice with alcoholic fatty liver disease. Cidea expression was significantly increased in the liver of alcohol-induced fatty liver mice. While, knockdown of Cidea caused lipid droplets numbers reduction. Next, we detected the activity of ALDH2 reduction and the concentration of serum acetaldehyde accumulation in our alcohol-induced fatty liver mice. Cidea expression was elevated in AML12 cells exposed to 100uM acetaldehyde. Interestingly, Dual-luciferase reporter gene assay showed that 100 uM acetaldehyde led to the activation of Cidea reporter gene plasmid which containing SRE element. What’s more, the knockdown of SREBP1c suppressed acetaldehyde-induced Cidea expression. Overall, our findings suggest that Cidea is highly associated with alcoholic fatty liver disease and Cidea expression is specifically induced by acetaldehyde, and this up-regulation is most likely mediated by SREBP1c.

Mimiviridae is a group of viruses with large genomes and virions. Ecological relevance of Mimiviridae in marine environments has been increasingly recognized through the discoveries of novel isolates and metagenomic studies. To facilitate ecological profiling of Mimiviridae, we previously proposed a meta-barcoding approach based on 82 degenerate primer pairs (i.e., MEGAPRIMER) targeting the DNA polymerase gene of Mimiviridae. The method detected a larger number of operational taxonomic units (OTUs) in environmental samples than previous methods. However, it required large quantities of DNA and was laborious due to the use of individual primer pairs. Here, we examined coastal seawater samples using varying PCR conditions and purification protocols to streamline the MEGAPRIMER method. Mixing primer pairs in “cocktails” reduced the required amount of environmental DNA by 90%, while reproducing the results obtained by the original protocol. We compared the results obtained by the meta-barcoding approach with quantifications using qPCR for selected OTUs. This revealed possible amplification biases among different OTUs, but the frequency profiles for individual OTUs across multiple samples were similar to those obtained by qPCR. We anticipate that the newly developed MEGAPRIMER protocols will be useful for ecological investigation of Mimiviridae in a larger set of environmental samples.

The transient contact-impact mechanism and driving capability of the piezoelectric stack actuator is analyzed using both experimental and theoretical methods. An experimental setup and its corresponding measurement approaches for the transient responses are designed. The launch range of the object resulting from the first contact-impact is measured through laser doppler vibrometer and the motion process is captured by high-speed camera. Experimental results illustrate that the launch range increases firstly and decreases subsequently as the frequency of the sine driving voltage increases. Meanwhile, considering the local viscoelastic contact deformation, a theoretical methodology including the mechanics model for the driving process is proposed. Based on the Lagrange equations of second kind, the governing equation of the driving system is derived. Transient responses are calculated using the fourth-order Runge−Kutta integration method. Contact forces and Poisson’s coefficient of restitution are calculated by the proposed theoretical method. The results of launch range show that the theoretical solutions have a good agreement with the experimental data. The peak value of contact force increases firstly and decreases subsequently with the increase of voltage frequency. In addition, the coefficient of restitutions is roughly 0.9 when f is greater than 3.5 kHz.

“Megaviridae” is a proposed family of giant viruses infecting unicellular eukaryotes. These viruses are ubiquitous in the sea and have impact on marine microbial community structure and dynamics through their lytic infection cycle. However, their diversity and biogeography have been poorly characterized due to the scarce detection of Megaviridae sequences in metagenomes, as well as the limitation of reference sequences used to design specific primers for this viral group. Here, we propose a set of 82 degenerated primers (referred to as MEGAPRIMER), targeting DNA polymerase genes (polBs) of Megaviridae. MEGAPRIMER was designed based on 921 Megaviridae polBs from sequenced genomes and metagenomes. By applying this primer set to environmental DNA meta-barcoding of a coastal seawater sample, we report 5595 non-singleton operational taxonomic units (OTUs) of Megaviridae at 97% nucleotide sequence identity. The majority of the OTUs were found to form diverse clades, which were phylogenetically distantly related to known viruses such as Mimivirus. The Megaviridae OTUs detected in this study outnumber the giant virus OTUs identified in previous individual studies by more than an order of magnitude. Hence, MEGAPRIMER represents a useful tool to study the diversity of Megaviridae at the population level in natural environments.

Dynamic buckling of thin-walled cylindrical shells under radial impact pressures randomly distributed in the circumferential direction is investigated by extending widely-used Donnell's shell theory. The buckling model proposed here specifically includes nonlinear terms in the geometrical equation and the curvature change due to significant variation of the shell radius. The finite difference method is adopted to solve the equations, and a parameter is defined to describe the buckling degree of the shell. Numerical results show that nonlinear terms from Green's strain tensors and the change of curvature are important for shell large deformation. Pressure characteristics, materials and thickness of the cylindrical shell affect its buckling behavior remarkably. [ABSTRACT FROM AUTHOR]

Abstract Background Tandem spinal stenosis (TSS) is a condition characterized by the narrowing of the spinal canal in multiple segments of the spine. Predominantly observed in the cervical and lumbar regions, TSS also manifests in the conjunction of the cervical and thoracic spine. The simultaneous occurrence of cervical and thoracic spinal stenosis engenders intricate symptoms, potentially leading to missed and delayed diagnosis. Furthermore, the presence of tandem cervical and thoracic stenosis (TCTS) introduces a notable impact on the decision-making calculus of surgeons when contemplating either one-staged or two-staged surgery. Currently, there is no agreed-upon strategy for surgical intervention of TCTS in the literature. Methods Medical databases in English (Pubmed, Web of Science, Embase, the Cochrane Database of Systematic Reviews) and Chinese (CNKI, Wanfang Data, VIP CMJD) were searched using Medical Subject Heading queries for the terms “tandem cervical and thoracic stenosis”, “cervical stenosis AND thoracic stenosis”, “tandem spinal stenosis” and “concomitant spinal stenosis” from January 1980 to March 2023. We included studies involving adult individuals with TCTS. Articles exclusively focused on disorders within a single spine region or devoid of any mention of spinal disorders were excluded. Results Initially, a total of 1625 literatures underwent consideration for inclusion in the study. Following the elimination of the duplicates through the utilization of EndNote, and a meticulous screening process involving scrutiny of abstracts and full-texts, 23 clinical studies met the predefined inclusion criteria. Of these, 2 studies solely focused on missed diagnosis, 19 studies exclusively discussed surgical strategy for TCTS, and 2 articles evaluated both surgical strategy and missed diagnosis. Conclusion Our study revealed a missed diagnosis rate of 7.2% in TCTS, with the thoracic stenosis emerging as the predominant area susceptible to oversight. Therefore, the meticulous identification of TCTS assumes paramount significance as the inaugural step in its effective management. While both one-staged and two-staged surgeries have exhibited efficacy in addressing TCTS, the selection of the optimal surgical plan should be contingent upon the individualized circumstances of the patients.