Markov Chain-based Clustering Analysis of Customers and WebPages

This paper focuses on users’ behavior towards an EC website. A novel Markov Chain-based way combining the web log file information and the topology of an EC website is presented to rank a user\u27s interest in a WebPage. Then a URL-USERID relevant matrix is set up, with URL taken as a row and USERID as column, and each element’s value is the probability of a user to access a WebPage when time goes infinitely. The similarity of each column vector can be used to cluster customers, and relevant web pages can be found from the similarity of each row vector. The knowledge discovered by this dynamic model can be fairly helpful to the design and maintenance of a website, to provide personalized service, and can be used in an effective recommending system of an EC website etc

Efficacy of relacin combined with sodium hypochlorite against Enterococcus faecalis biofilms

Objective: Relacin is a synthetic molecule that targets RelA, an essential protein in a conserved bacterial stress response system. It was shown to inhibit bacterial growth. The aims of this study were to evaluate the antimicrobial effect of relacin combined with sodium hypochlorite (NaOCl) on Enterococcus faecalis biofilms and to evaluate the cytotoxicity of relacin. Material and Methods: 48-h E. faecalis OG1RF biofilms were treated by various concentrations of relacin in order to determine its inhibitory concentration. Then, the 48-h biofilms were treated either with 1-min NaOCl (0.01%, 0.05%) alone, or in combination of relacin. As a means of comparison, the biofilms of ΔrelA were also treated by 1-min NaOCl (0.01%, 0.05%, 0.25%). The treatment efficacy was determined by agar plate count assays. The cytotoxicity of relacin was examined on human gingival epithelial cells Ca9-22 and murine fibroblasts NIH-3T3 by a methyl thiazolyltetrazolium (MTT) assay and a lactate dehydrogenase assay. Statistical analysis was performed by one-way or two-way analysis of variance (ANOVA) with Bonferroni’s post-hoc test and an independent Student’s t-test. A significance level of p<0.05 was used. Results: Relacin inhibited the growth of OG1RF biofilms partially at 8 mM and fully at 14 mM. The relacin (14 mM) and NaOCl combined treatment resulted in significantly higher treatment efficacy than NaOCl treatment alone. At 0.05% NaOCl, the combined treatment resulted in 5.65 (±0.19) log reduction in biofilm viability. The ΔrelA biofilms were more susceptible to NaOCl treatment than the wild type biofilms at 0.25% NaOCl. Relacin at 14 mM was not toxic to host epithelial cells and fibroblasts. Conclusions: The combination of relacin with a low concentration of NaOCl was effective and not cytotoxic

Serum retinol-binding protein 4 levels are elevated but do not contribute to insulin resistance in newly diagnosed Chinese hypertensive patients

BACKGROUND: Insulin resistance (IR) is closely correlated with cardiovascular disease (CVD). Retinol-binding protein 4 (RBP4) is a novel adipokine that modulates the action of insulin in various diseases. This study addressed the relationship between RBP4 and IR in newly diagnosed essential hypertension. METHODS: Serum RBP4, anthropometric and metabolic parameters were determined in 267 newly diagnosed essential hypertensive patients not taking antihypertensive medications. The patients along with 64 control (NC) normotensive and lean subjects paired by age and sex were divided into two groups depending on body mass index (BMI), hypertension with obesity (HPO) and hypertension without obesity (HP). RESULTS: A striking difference was observed in RBP4 levels between the HP and NC groups. Significantly higher levels were noted in the HP group compared with the NC group; slightly, but not significantly, lower levels were observed in the HPO group compared with the HP group. After adjusting for BMI, WC and WHR, a modestly linear relationship was observed between RBP4 levels and SBP (r = 0.377; p = 0.00), DBP (r = 0.288; p = 0.00) and HOMA-β(r = 0.121; p = 0.028). Multiple stepwise regression analysis showed that SBP, WHR and drinking were independently related with serum RBP4 levels. CONCLUSIONS: The results of this study indicated that RBP4 levels were increased in naive hypertensive patients; however, no differences were observed in obese or non-obese hypertensive subjects. Our data suggest for the first time that RBP4 levels are significantly increased but do not contribute to the development of IR in newly diagnosed hypertensive Chinese patients

Chemical composition of the volatile oil of Chenopodium ambrosioides L. from Mianyang in Sichuan Province of China and its sub-chronic toxicity in mice

Purpose: To determine the chemical constituents of the volatile oil of Chenopodium ambrosioides L. from Mianyang in Sichuan Province of China, and assess the sub-chronic toxicity of the volatile oil in mice.Methods: The volatile chemical components were analyzed by gas chromatography-mass spectrometry (GC-MS). Sixty Kunming mice were divided into six groups of ten mice each. One group served as control (no treatment), two groups were orally administered ρ-cymene at doses of 3 and 7 mg/kg, respectively, for 27 days, while three groups received the volatile oil at doses of 10, 25 and 40 mg/kg, respectively, for the same duration. Sub-chronic toxicity in the mice was evaluated by observing their general behavior, measuring serum levels of aspartate transaminase (AST) and alanine transaminase (ALT), evaluating liver, heart, kidney and thymus indices, and assessing the histological morphology of the organs.Results: The volatile oil contained 14 chemical components, of which α-terpinene and ρ-cymene accounted for 32.89 and 24.25 %, respectively. The volatile oil caused significant (p < 0.05) increase in liver index, and serum AST and ALT levels, and also induced distinct morphological changes in mouse liver, heart and kidney.Conclusion: The main volatile components of the oil are α-terpinene and ρ-cymene. The volatile oil showed dose-dependent toxicity in mice, thus lending some support for the safe use of C. ambrosioides in traditional medicine. Keywords: Chenopodium ambrosioides, Volatile oil, Oral toxicity, AST and ALT, Histopathological change

Strong Electronic Interaction of Amorphous Fe2O3 Nanosheets with Single‐Atom Pt toward Enhanced Carbon Monoxide Oxidation

Platinum‐based catalysts are critical to several chemical processes, but their efficiency is not satisfying enough in some cases, because only the surface active‐site atoms participate in the reaction. Henceforth, catalysts with single‐atom dispersions are highly desirable to maximize their mass efficiency, but fabricating these structures using a controllable method is still challenging. Most previous studies have focused on crystalline materials. However, amorphous materials may have enhanced performance due to their distorted and isotropic nature with numerous defects. Here reported is the facile synthesis of an atomically dispersed catalyst that consists of single Pt atoms and amorphous Fe2O3 nanosheets. Rational control can regulate the morphology from single atom clusters to sub‐nanoparticles. Density functional theory calculations show the synergistic effect resulted from the strong binding and stabilization of single Pt atoms with the strong metal‐support interaction between the in situ locally anchored Pt atoms and Fe2O3 lead to a weak CO adsorption. Moreover, the distorted amorphous Fe2O3 with O vacancies is beneficial for the activation of O2, which further facilitates CO oxidation on nearby Pt sites or interface sites between Pt and Fe2O3, resulting in the extremely high performance for CO oxidation of the atomic catalyst.An atomically Pt dispersed catalyst on amorphous Fe2O3 nanosheets is developed. The size effect of Pt and phase effect of support are explored. The synergistic effect results from the strong metal‐support interactions between the single Pt atoms and the amorphous Fe2O3 structure supports lead to an enhanced CO oxidation performance.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151833/1/adfm201904278-sup-0001-S1.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151833/2/adfm201904278.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151833/3/adfm201904278_am.pd

CagA-positive Helicobacter pylori may promote and aggravate scrub typhus

Helicobacter pylori (H. pylori) infection may alter the host’s resistance to tsutsugamushi disease pathogens through the Th1 immune response, leading to potential synergistic pathogenic effects. A total of 117 scrub typhus cases at Beihai People’s Hospital and affiliated hospitals of Youjiang University for Nationalities and Medical Sciences were studied from January to December 2022, alongside 130 healthy individuals forming the control group. All participants underwent serum H. pylori antibody testing. The prevalence of H. pylori infection was significantly higher among scrub typhus patients (89.7%) compared to healthy individuals (54.6%) (p < 0.05). Moreover, type I H. pylori infection was notably more prevalent in scrub typhus cases (67.5%) compared to healthy individuals (30%) (p < 0.05). Multifactorial analysis demonstrated type I H. pylori infection as an independent risk factor for scrub typhus (adjusted odds ratio: 2.407, 95% confidence interval: 1.249–4.64, p = 0.009). Among scrub typhus patients with multiple organ damage, the prevalence of type I H. pylori infection was significantly higher (50.6%) than type II H. pylori infection (15.4%) (χ2 = 4.735, p = 0.030). These results highlight a higher incidence of H. pylori infection in scrub typhus patients compared to the healthy population. Additionally, type I H. pylori strain emerged as an independent risk factor for scrub typhus development. Moreover, individuals infected with type I H. pylori are more susceptible to multiple organ damage. These findings suggest a potential role of H. pylori carrying the CagA gene in promoting and exacerbating scrub typhus

Identification of three species commonly known as “daqingye” by internal leaf anatomy and high-performance liquid chromatography analyses

The macroscopic and microscopic morphologies and indigo and indirubin concentration of the traditional Chinese medicine herbs Isatis indigotica Fort., Polygonum tinctorium Ait., and Baphicacanthus cusia (Nees) Bremek, all commonly known as “daqingye”, were determined and compared. The morphological analyses indicated that I. indigotica has leaves with winged petioles and no glandular hairs or crystals, P. tinctorium has leaves with membranous ocrea and clusters of calcium oxalate, and B. cusia has palisade cells in the mesophyll running over the main vein and single cells containing calcium carbonate crystals. Indigo and indirubin are chemical constituents that have been previously isolated from daqingye and were selected in this study as identification markers for high-performance liquid chromatography analysis due to their pharmacological activities. The chromatographic results showed that indigo and indirubin concentration varied significantly among the three species: high concentration of both indigo and indirubin were observed in I. indigotica, the highest concentration among the three daqingye plants was found in P. tinctorium but with low levels of indirubin, and the concentration of indigo and indirubin was quite low in B. cusia. In summary, three different species commonly known as daqingye were accurately distinguished by morphological observation, internal leaf anatomy analysis, and chromatographic analysis

Risk Taxonomy, Mitigation, and Assessment Benchmarks of Large Language Model Systems

Large language models (LLMs) have strong capabilities in solving diverse natural language processing tasks. However, the safety and security issues of LLM systems have become the major obstacle to their widespread application. Many studies have extensively investigated risks in LLM systems and developed the corresponding mitigation strategies. Leading-edge enterprises such as OpenAI, Google, Meta, and Anthropic have also made lots of efforts on responsible LLMs. Therefore, there is a growing need to organize the existing studies and establish comprehensive taxonomies for the community. In this paper, we delve into four essential modules of an LLM system, including an input module for receiving prompts, a language model trained on extensive corpora, a toolchain module for development and deployment, and an output module for exporting LLM-generated content. Based on this, we propose a comprehensive taxonomy, which systematically analyzes potential risks associated with each module of an LLM system and discusses the corresponding mitigation strategies. Furthermore, we review prevalent benchmarks, aiming to facilitate the risk assessment of LLM systems. We hope that this paper can help LLM participants embrace a systematic perspective to build their responsible LLM systems

A Non‐Pt Electronically Coupled Semiconductor Heterojunction for Enhanced Oxygen Reduction Electrocatalytic Property

Hybrid faceted‐Ag3PO4/cube‐Cu2O composite materials have been fabricated and employed as oxygen reduction electrocatalysts for proton exchange membrane fuel cells (PEMFCs). The charge separation effect via the formation of PN junction has been demonstrated to boost the electrocatalysis toward oxygen reduction reaction. The as‐prepared rhombic dodecahedron‐Ag3PO4/cube‐Cu2O/C hybrid catalyst shows a mass‐specific activity of 109.80 mA/mgAg, which is about 6.4 times that of pure rhombic dodecahedron‐Ag3PO4/C catalyst (17.20 mA/mgAg). The density functional theory (DFT) calculation based on the density of states (DOS) further proved the optimal tunable effect, which is in pace with demonstration of electron transfer direction revealed by X‐ray photoelectron spectroscopy (XPS) analysis. Our work establishes a theoretical and practical basis for the rational design of newly non‐Pt hybrid catalysts, moreover, advances the future efficient application of PEMFCs.A cost effective electronically coupled semiconductor heterojunction between facet‐Ag3PO4 and Cu2O cube is reported. Its high electrocatalytic activity towards oxygen reduction reaction (ORR) indicates that electron distribution can be controlled through the interfacial engineering between Ag3PO4 and Cu2O. This paves way to rationally design new non‐Pt hybrid catalysts, and moreover advances the future efficient applications of proton exchange membrane fuel cells (PEMFCs).Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149290/1/slct201900615.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149290/2/slct201900615-sup-0001-misc_information.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149290/3/slct201900615_am.pd