Application of machine learning for risky sexual behavior interventions among factory workers in China

IntroductionAssessing the likelihood of engaging in high-risk sexual behavior can assist in delivering tailored educational interventions. The objective of this study was to identify the most effective algorithm and assess high-risk sexual behaviors within the last six months through the utilization of machine-learning models.MethodsThe survey conducted in the Longhua District CDC, Shenzhen, involved 2023 participants who were employees of 16 different factories. The data was collected through questionnaires administered between October 2019 and November 2019. We evaluated the model's overall predictive classification performance using the area under the curve (AUC) of the receiver operating characteristic (ROC) curve. All analyses were performed using the open-source Python version 3.9.12.ResultsAbout a quarter of the factory workers had engaged in risky sexual behavior in the past 6 months. Most of them were Han Chinese (84.53%), hukou in foreign provinces (85.12%), or rural areas (83.19%), with junior high school education (55.37%), personal monthly income between RMB3,000 (US$417.54) and RMB4,999 (US$695.76; 64.71%), and were workers (80.67%). The random forest model (RF) outperformed all other models in assessing risky sexual behavior in the past 6 months and provided acceptable performance (accuracy 78%; sensitivity 11%; specificity 98%; PPV 63%; ROC 84%).DiscussionMachine learning has aided in evaluating risky sexual behavior within the last six months. Our assessment models can be integrated into government or public health departments to guide sexual health promotion and follow-up services

Horizontal gene transfer is predicted to overcome the diversity limit of competing microbial species

Abstract Natural microbial ecosystems harbor substantial diversity of competing species. Explaining such diversity is challenging, because in classic theories it is extremely infeasible for a large community of competing species to stably coexist in homogeneous environments. One important aspect mostly overlooked in these theories, however, is that microbes commonly share genetic materials with their neighbors through horizontal gene transfer (HGT), which enables the dynamic change of species growth rates due to the fitness effects of the mobile genetic elements (MGEs). Here, we establish a framework of species competition by accounting for the dynamic gene flow among competing microbes. Combining theoretical derivation and numerical simulations, we show that in many conditions HGT can surprisingly overcome the biodiversity limit predicted by the classic model and allow the coexistence of many competitors, by enabling dynamic neutrality of competing species. In contrast with the static neutrality proposed by previous theories, the diversity maintained by HGT is highly stable against random perturbations of microbial fitness. Our work highlights the importance of considering gene flow when addressing fundamental ecological questions in the world of microbes and has broad implications for the design and engineering of complex microbial consortia

Middle and Upper Ordovician Chitinozoans from the Kuruktag Area, northeastern Tarim, China

International audienc

High Conductivity and Adhesion of Cu-Cr-Zr Alloy for TFT Gate Electrode

The characteristics of Cu alloy (0.3 wt. % Cr, 0.2 wt. % Zr) thin film deposited by direct current (DC) magnetron sputtering deposition were investigated. The conductivity and adhesion of the Cu-0.3%Cr-0.2%Zr films were optimized by increasing the sputter power to 150 W and reducing the sputter pressure to 2 mTorr. With an annealing process (at 300 °C for 1 h in argon ambient atmosphere), the resistivity of the alloy film decreased from 4.80 to 2.96 μΩ·cm, and the adhesion classification increased from 2B to 4B on glass substrate. X-ray photoelectron spectroscopy (XPS) analysis showed that Cr aggregated toward the surface of the film and formed a self-protection layer in the annealing process. Transmission electron microscopy (TEM) indicated the aggregation and migration of Cr in the annealing process. A further X-ray diffraction (XRD) analysis showed that Cu2O appeared when the annealing temperature reached above 350 °C, which accounts for the increase of the resistivity. Based on Al2O3 and SiO2 substrate surfaces, the Cu-0.3%Cr-0.2%Zr film also showed high conductivity and adhesion, which has a potential in the application of Cu gate electrodes for thin film transistor (TFT)

Direct Inkjet Printing of Silver Source/Drain Electrodes on an Amorphous InGaZnO Layer for Thin-Film Transistors

Printing technologies for thin-film transistors (TFTs) have recently attracted much interest owing to their eco-friendliness, direct patterning, low cost, and roll-to-roll manufacturing processes. Lower production costs could result if electrodes fabricated by vacuum processes could be replaced by inkjet printing. However, poor interfacial contacts and/or serious diffusion between the active layer and the silver electrodes are still problematic for achieving amorphous indium–gallium–zinc–oxide (a-IGZO) TFTs with good electrical performance. In this paper, silver (Ag) source/drain electrodes were directly inkjet-printed on an amorphous a-IGZO layer to fabricate TFTs that exhibited a mobility of 0.29 cm2·V−1·s−1 and an on/off current ratio of over 105. To the best of our knowledge, this is a major improvement for bottom-gate top-contact a-IGZO TFTs with directly printed silver electrodes on a substrate with no pretreatment. This study presents a promising alternative method of fabricating electrodes of a-IGZO TFTs with desirable device performance