Existence of Positive Periodic Solutions for a Class of n-Species Competition Systems with Impulses

By using the fixed point theorem on cone, some sufficient conditions are obtained on the existence of positive periodic solutions for a class of n-species competition systems with impulses. Meanwhile, we point out that the conclusion of Yan, 2009 is incorrect

Versatile manipulation of low-refractive-index particles using customized optical building blocks

Low-refractive-index (LRI) particles play significant roles in physics, drug delivery, biomedical science, and other fields. However, they have not attained sufficient utilization in active manipulation due to the repulsive effect of light. Here, we demonstrate the establishment of optical building blocks (OBBs) to fulfill the demands of versatile manipulation of LRI particles. The OBBs are generated by assembling generalized perfect optical vortices based on the free lens modulation (FLM) method, by which the beams shape, intensity, and position can be elaborately designed with size independent of topological charge. Using the OBBs with high quality and high efficiency, we realized rotating LRI particles along arbitrary trajectories with controllable speed and parallel manipulation of multiple LRI particles. Importantly, we further achieved the sorting of LRI particles by size with specially structured OBBs. With unprecedented flexibility and quality, OBBs provide tremendous potential in optical trapping, lithography, and biomedicine.Comment: 13 pages, 5 figures, corresponding authors:Yansheng Liang and Ming Le

Prediction of hyperuricemia in people taking low-dose aspirin using a machine learning algorithm: a cross-sectional study of the National Health and Nutrition Examination Survey

Background: Hyperuricemia is a serious health problem related to not only gout but also cardiovascular diseases (CVDs). Low-dose aspirin was reported to inhibit uric acid excretion, which leads to hyperuricemia. To decrease hyperuricemia-related CVD, this study aimed to identify the risk of hyperuricemia in people taking aspirin.Method: The original data of this cross-sectional study were obtained from the National Health and Nutrition Examination Survey between 2011 and 2018. Participants who filled in the “Preventive Aspirin Use” questionnaire with a positive answer were included in the analysis. Six machine learning algorithms were screened, and eXtreme Gradient Boosting (XGBoost) was employed to establish a model to predict the risk of hyperuricemia.Results: A total of 805 participants were enrolled in the final analysis, of which 190 participants had hyperuricemia. The participants were divided into a training set and testing set at a ratio of 8:2. The area under the curve for the training set was 0.864 and for the testing set was 0.811. The SHapley Additive exPlanations (SHAP) method was used to evaluate the performances of the modeling. Based on the SHAP results, the feature ranking interpretation showed that the estimated glomerular filtration rate, body mass index, and waist circumference were the three most important features for hyperuricemia in individuals taking aspirin. In addition, triglyceride, hypertension, total cholesterol, high-density lipoprotein, low-density lipoprotein, age, race, and smoking were also correlated with the development of hyperuricemia.Conclusion: A predictive model established by XGBoost algorithms can potentially help clinicians make an early detection of hyperuricemia risk in people taking low-dose aspirin

Dynamic changes of rumen bacteria and their fermentative ability in high-producing dairy cows during the late perinatal period

BackgroundHigh-producing dairy cows face varying degrees of metabolic stress and challenges during the late perinatal period, resulting in ruminal bacteria abundance and their fermentative ability occurring as a series of changes. However, the dynamic changes are still not clear.Aims/methodsTen healthy, high-producing Holstein dairy cows with similar body conditions and the same parity were selected, and ruminal fluid from the dairy cows at postpartum 0, 7, 14, and 21 d was collected before morning feeding. 16S rRNA high-throughput sequencing, GC-MS/MS targeted metabolomics, and UPLC-MS/MS untargeted metabolomics were applied in the study to investigate the dynamic changes within 21 d postpartum.ResultsThe results displayed that the structures of ruminal bacteria were significantly altered from 0 to 7 d postpartum (R = 0.486, P = 0.002), reflecting the significantly declining abundances of Euryarchaeota and Chloroflexi phyla and Christensenellaceae, Methanobrevibacter, and Flexilinea genera (P < 0.05) and the obviously ascending abundances of Ruminococcaceae, Moryella, Pseudobutyrivibrio, and Prevotellaceae genera at 7 d postpartum (P < 0.05). The structures of ruminal bacteria also varied significantly from 7 to 14 d postpartum (R = 0.125, P = 0.022), reflecting the reducing abundances of Christensenellaceae, Ruminococcaceae, and Moryella genera (P < 0.05), and the elevating abundances of Sharpea and Olsenella genera at 14 d postpartum (P < 0.05). The metabolic profiles of ruminal SCFAs were obviously varied from 0 to 7 d postpartum, resulting in higher levels of propionic acid, butyric acid, and valeric acid at 7 d postpartum (P < 0.05); the metabolic profiles of other ruminal metabolites were significantly shifted from 0 to 7 d postpartum, with 27 significantly elevated metabolites and 35 apparently reduced metabolites (P < 0.05). The correlation analysis indicated that propionic acid was positively correlated with Prevotellaceae and Ruminococcaceae (P < 0.05), negatively correlated with Methanobrevibacter (P < 0.01); butyric acid was positively associated with Prevotellaceae, Ruminococcaceae, and Pseudobutyrivibrio (P < 0.05), negatively associated with Christensenellaceae (P < 0.01); valeric acid was positively linked with Prevotellaceae and Ruminococcaceae (P < 0.05); pyridoxal was positively correlated with Flexilinea and Methanobrevibacter (P < 0.05) and negatively correlated with Ruminococcaceae (P < 0.01); tyramine was negatively linked with Ruminococcaceae (P < 0.01).ConclusionThe findings contribute to the decision of nutritional management and prevention of metabolic diseases in high-producing dairy cows during the late perinatal period

Bacillus subtilis Inhibits Vibrio natriegens-Induced Corrosion via Biomineralization in Seawater

The marine bacterium, Vibrio natriegens, grows quickly in a marine environment and can significantly accelerate the corrosion of steel materials. Here, we present an approach to inhibit V. natriegens-induced corrosion by biomineralization. The corrosion of steel is mitigated in seawater via the formation of a biomineralized film induced by Bacillus subtilis. The film is composed of extracellular polymeric substances (EPS) and calcite, exhibiting stable anti-corrosion activity. The microbial diversity and medium chemistry tests demonstrated that the inhibition of V. natriegens growth by B. subtilis was essential for the formation of the biomineralized film

Minocycline protects neurons against glial cells-mediated bilirubin neurotoxicity

Unconjugated bilirubin, the end product of heme catabolism and antioxidant, induced brain damage in human neonates is a well-recognized clinical syndrome. However, the cellular and molecular mechanisms underlying bilirubin neurotoxicity remain unclear. To characterize the sequence of events leading to bilirubin-induced neurotoxicity, we investigated whether bilirubin-induced glial activation was involved in bilirubin neurotoxicity by exposing co-cultured rat glial cells and cerebellar granule neurons (CGN) to bilirubin. We found that bilirubin could markedly induce the expression of TNF-α and iNOS in glial cells, and even at low concentrations, the co-culture of glial cells with neurons significantly enhances neurotoxicity of bilirubin. Pretreatment of the co-cultured cells with minocycline protected CGN from glia-mediated bilirubin neurotoxicity and inhibited overexpression of TNF-α and iNOS in glia. Furthermore, we found that high doses of bilirubin were able to induce glial injury, and minocycline attenuated bilirubin-induced glial cell death. Our data suggest that glial cells play an important role in brain damage caused by bilirubin, and minocycline blocks bilirubin-induced encephalopathy possibly by directly and indirectly inhibiting neuronal death pathways

Existence of Positive Periodic Solutions for a Class of n-Species Competition Systems with Impulses

By using the fixed point theorem on cone, some sufficient conditions are obtained on the existence of positive periodic solutions for a class of n-species competition systems with impulses. Meanwhile, we point out that the conclusion of (Yan, 2009) is incorrect

Association of red cell distribution width with pulmonary arterial hypertension in patients with mixed connective tissue disease

Abstract Background Pulmonary arterial hypertension (PAH) is a severe complication of mixed connective tissue disease (MCTD) and contributes to increased morbidity and mortality. Still, the demographic characteristics and risk factors of PAH in MCTD remain poorly understood. This study explored risk factors for PAH development in MCTD. Methods Data from patients with MCTD and PAH hospitalized from May 2009 to December 2022 in a single center were collected and compared with patients with MCTD without PAH. The variables were analyzed by logistic regression to identify the factors associated with PAH in patients with MCTD. The receiver-operating characteristic (ROC) curve was used to assess the diagnostic value of the identified factors. Results Finally, 119 patients with MCTD were included; 46 had PAH. The mean age at PAH onset and diagnosis was 38.9 ± 13.4 and 39.9 ± 13.7 years, respectively. The median pulmonary arterial systolic pressure (PASP) was 67.0 mmHg. The median brain natriuretic peptide (BNP) level was 180.0 pg/ml at PAH diagnosis. Red cell distribution width (RDW) (OR: 2.128; 95% confidence interval: 1.497–3.026; P < 0.001) was associated with PAH in patients with MCTD. There was a positive correlation between RDW and PASP (r = 0.716, P < 0.001). At a cutoff of 15.2%, RDW had the best sensitivity (80.4%) and specificity (82.2%) for PAH. Conclusion RDW may serve as a sensitive index to predict PAH in patients with MCTD

A study of the non-parabolic hydrodynamic modelling of a sub-micrometre n\u3csup\u3e+\u3c/sup\u3e-n-n\u3csup\u3e+\u3c/sup\u3e device

The common assumptions for closure of the first three moment equations with non-parabolic band structure have led to many inconsistencies associated with the electron temperature, effective mass and heat flux. The assumptions are involved in the heat flux based on the Fourier law and in the electron temperature determined from the average kinetic and drift energies. The inconsistencies resulting from these assumptions are studied and illustrated for electrons in silicon with a non-parabolic energy band. A simple alternative by means of which to avoid the inconsistent assumptions and to truncate the hierarchy of the hydrodynamic equations with non-parabolic band structure is proposed. Instead of using the Fourier-law heat flux to close the hydrodynamic equations, the energy flux is separated into fluxes carried by average and random velocities. The proposed model and a Fourier-law-based hydrodynamic model, together with the Monte Carlo method, are applied to a silicon sub-micrometre n+-n-n+ diode with a non-parabolic band at various applied voltages. Effects on electron transport in the sub-micrometre device resulting from the assumptions of the Fourier-law heat flux and the electron temperature determined from the average kinetic and drift energies are investigated