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Electroencephalogram (EEG) signals play an important role in brain-computer interface (BCI) applications. Recent studies have utilized transfer learning to assist the learning task in the new subject, i.e., target domain, by leveraging beneficial information from previous subjects, i.e., source domains. Nevertheless, EEG signals involve sensitive personal mental and health information. Thus, privacy concern becomes a critical issue. In addition, existing methods mostly assume that a portion of the new subject’s data is available and perform alignment or adaptation between the source and target domains. However, in some practical scenarios, new subjects prefer prompt BCI utilization over the time-consuming process of collecting data for calibration and adaptation, which makes the above assumption difficult to hold. To address the above challenges, we propose Online Source-Free Transfer Learning (OSFTL) for privacy-preserving EEG classification. Specifically, the learning procedure contains offline and online stages. At the offline stage, multiple model parameters are obtained based on the EEG samples from multiple source subjects. OSFTL only needs access to these source model parameters to preserve the privacy of the source subjects. At the online stage, a target classifier is trained based on the online sequence of EEG instances. Subsequently, OSFTL learns a weighted combination of the source and target classifiers to obtain the final prediction for each target instance. Moreover, to ensure good transferability, OSFTL dynamically updates the transferred weight of each source domain based on the similarity between each source classifier and the target classifier. Comprehensive experiments on both simulated and real-world applications demonstrate the effectiveness of the proposed method, indicating the potential of OSFTL to facilitate the deployment of BCI applications outside of controlled laboratory settings.

Abstract Background Multiple rib fractures can lead to flail chest with up to 35% mortality rate due to severe pulmonary complications. Current treatments of flail chest remain controversial. Studies have shown that surgical treatments can improve outcomes and reduce mortality, comparing to non-operative treatments. Current surgical fixation methods focus on stabilization of ribs on the outward facing side, and they require division of intercostal muscles. Damages to surrounding nerves and vessels may lead to chronic pain. This study tests a novel interior fixation method that minimizes neurovascular injuries. Methods Twelve healthy canines were divided in two surgical operation groups for exterior and interior fixation using titanium metal plates. Osteotomy with oblique fractures was prepared under general anesthesia. Exterior fixation was performed in open surgery. Interior fixation was minimally invasive using custom made tools including a flexible shaft extension screwdriver, solid plate stand, guiding wire loop and metal plates with threaded holes. Results Respiratory and cardiovascular functions (RR, PO2, PCO2, SpO2, and HR) together with body temperature were measured before anesthesia and within 48 h after surgery. The difference in measurements was not statistically significant between the two groups before surgery with P values greater than 0.05. However, the interior group canines had better RR and PO2 values starting from the 24th hour, and better PCO2, SpO2, and HR values starting from the 48th hour. It took longer operation time to complete the minimally invasive interior fixation surgery (P value less than 0.001), but the total blood loss was less than the exterior fixation group (P value less than 0.001). Results also showed that interior group canines suffered less pain, and they had quicker recovery in gastrointestinal and physical mobility. Conclusions The investigative interior fixation method was safe and effective in rib stabilization on a canine rib fracture model, comparing to the exterior fixation method. The interior fixation was minimally invasive, with less damages to tissues and nerves surrounding the ribs, leading to better postoperative outcomes.

The aim of the present work is to evaluate the effect of ultrafast heating on the microstructure and mechanical properties of hot forming steel. The initial microstructure utilized in this study was a cold-rolled microstructure, and the test steel was heated to full austenitization at a rate of 200 °C/s, followed by water quenching. It was observed that the ultrafast heating process significantly refines both the prior austenite grains and martensite laths while inheriting high-density dislocations from the initial cold-rolled microstructure. Consequently, the coupling mechanism between dislocation strengthening and grain refinement strengthening remarkably enhanced both the yield strength and ultimate tensile strength of the test steel. Eventually, the yield strength of the hot forming steel reached 1524 MPa, along with an ultimate tensile strength of 2221 MPa and uniform elongation of 5.2%.

The fatigue crack initiation and propagation in Nb–Ti micro-alloyed 500 MPa grade steels that usually be used in the automobile beam were investigated. Reducing the content of C and Mn elements based on the reference steel and adding microalloying elements Nb and Ti to obtain the modified steel. The fatigue strengths of the reference steel and the modified steel are 201 MPa and 225 MPa, respectively. Fatigue cracks in the experimental steel were initiated at surface defects and persistent slip bands (PSBs). The modified steel is more susceptible to initiating cracks at the PSBs than the reference steel. There were three kinds of fracture modes in the experimental steels, which were determined by the competition between carbide and inclusion. As the loading stress and the stress intensity factor (Δk) increase, the fracture mode transforms from cleavage (brittle) to dimple (ductile) fracture. Under the circumstance of low loading stress and low Δk, the fracture mode is dominated by the carbide-induced cleavage fracture mechanism. Under the situation of high loading stress and Δk, the fracture mode is dominated by the inclusion-induced dimple fracture mechanism. In addition, the mixed cleavage-dimple region is formed when the two fracture mechanisms compete in the steel.

The surface of hot stamping steel is severely oxidized during heating, holding, and transfer from the heating furnace to the stamping die in the production of traditional automotive parts. Coating-free hot stamping steel with Cr and Si elements exhibits excellent oxidation resistance during hot stamping without the protection of a surface coating. This paper investigates the oxidation behavior of three types of hot stamping steel at 800–1200 °C. The results show that although Cr-Si hot stamping steel performs excellently short-term (≤7.5 min) for oxidation resistance, its long-term (≥15 min) or high-temperature (≥1100 °C) oxidation resistance is much lower than that of the conventional hot stamping steel 22MnB5, affecting the production and surface quality control of the new coating-free Cr-Si hot stamping steel. By analyzing the oxidation kinetics and characterizing the structure of oxide layers in hot stamping steel, it was found that the structural change in the Cr and Si element enrichment layer between the oxide scale and the substrate varied in oxidation performance at different temperatures. When the oxidation temperature was below 1000 °C, the solid Cr and Si enrichment layer acted as a barrier to prevent the diffusion of Fe ions. When the oxidation temperature exceeded 1100 °C, the molten Cr and Si enrichment layer effectively adapted to the substrate and avoided blistering. Meanwhile, Fe2SiO4 penetrated the Fe oxide layer along the grain boundary and became a rapidly diffusing channel of Fe ions, contributing to a significant increase in the oxidation rate.

Abstract Background Pregnant women experience physical, physiological, and mental changes. Health-related quality of life (HRQoL) is a relevant indicator of psychological and physical behaviours, changing over the course of pregnancy. This study aims to assess HRQoL of pregnant women during different stages of pregnancy. Methods This cross-sectional study was performed using the The EuroQoL Group’s five-dimension five-level questionnaire (EQ-5D-5L) to assess the HRQoL of pregnant women, and demographic data were collected. This study was conducted in a regional university hospital in Guangzhou, China. Results A total of 908 pregnant women were included in this study. Pregnant women in the early 2nd trimester had the highest HRQoL. The HRQoL of pregnant women rose from the 1st trimester to the early 2nd trimester, and dropped to the bottom at the late 3rd trimester due to some physical and mental changes. Reports of pain/discomfort problem were the most common (46.0%) while self-care were the least concern. More than 10% of pregnant women in the 1st trimester had health-related problems in at least one dimension of whole five dimensions. In the whole sample, the EuroQoL Group’s visual analog scale (EQ-VAS) was 87.86 ± 9.16. Across the gestational stages, the HRQoL remained stable during the pregnancy but the highest value was observed in the 1st trimester (89.65 ± 10.13) while the lowest was in the late 3rd trimester (87.28 ± 9.13). Conclusions During pregnancy, HRQoL were associated with gestational trimesters in a certain degree. HRQoL was the highest in the early 2nd trimester and then decreased to the lowest in the late 3rd trimester due to a series of physical and psychological changes. Therefore, obstetric doctors and medical institutions should give more attention and care to pregnant women in the late 3rd trimester.

Abstract Background With the increase of the number of smokers, tobacco exposure among pregnant women is becoming more and more common. Pregnant women exposed to first-hand smoke and second-hand smoke are susceptible to physiological and psychological health issues has been proved in previous studies. Nevertheless, there are no enough studies focus on the impact of third-hand smoke during pregnancy. This study aimed to assess and compare health-related quality of life for pregnant women with exposure to first-hand smoke, second-hand smoke, third-hand smoke and non-exposure to tobacco in mainland China. Methods National-based cross-sectional study is based on a questionnaire survey which collects information including demographics, smoking behaviors and self-evaluation. All questionnaires were delivered and collected from August to September 2019. EuroQol group’s visual analog scale and EuroQoL Five-dimension Questionnaire were used to collect data in mainland China. Results Totally, 15,682 pregnant women were included in this study, among which non-exposure to smoke were 7564 (48.2%), exposed to first-hand smoke, second-hand smoke and third-hand smoke were 89 (0.6%), 2349 (15.0%), and 5680 (36.2%) respectively. Pregnant women without tobacco exposure had the highest EuroQol group’s visual analog scale score (mean value = 85.4[SD = 14.0]), while those with first-hand smoke had the lowest score (mean value = 77.4[SD = 22.2]). Among all five dimensions of EuroQoL Five-dimension Questionnaire, there were significant differences of EQ-index among groups with different tobacco exposure in usual activity and anxiety or depression dimensions (p

Abstract Background Circular RNAs (circRNAs) has emerged as vital regulator involved in various diseases. In this study, we identified and investigated the potential circRNAs involved in gestational diabetes mellitus (GDM). Methods High-throughput sequencing was used to collect the plasma circRNAs expression profiles of GDM patients. Quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) was used to measure the expressions of circ_0008285 and circ_0001173 in the plasma specimens. The Pearson’s correlation test was employed to assess the correlation between 2 circRNAs expression and the clinicopathologic data. Two circRNAs expression was verified in high glucose (HG)-induced HTR-8/SVneo cells. MTS, transwell assay was used to evaluate the effects of circ_0008285 expression on HG-induced HTR-8/SVneo cells. The network of circ_0008285 was constructed using cytocape. Results In GDM patients, the expression of circ_0008285 was significantly upregulated, while that of circ_0001173 was decreased. Circ_0008285 was significantly correlated with the total cholesterol and LDL-C levels. Circ_0001173 was significantly correlated with glycated hemoglobin. HG promoted the proliferation, invasion, and migration in HTR-8/SVneo cells, while the knockdown of circ_0008285 exerted reverse effects. In addition, network construction exhibited that circ_0008285 had 45 miRNA binding sites, which correlated with 444 mRNA. Conclusions circ_0008285 plays an important role and provides a clue for the usage of therapeutic targets in the development of GDM.

Abstract Background Pregnancy tests can be used for the early diagnosis of fetal problems and can prevent abnormal birth in pregnancies. Yet, testing preferences among Chinese women are poorly investigated. Methods We developed a Discrete Choice Experiment with 5 attributes: test procedure, detection rate, miscarriage rate, time to wait for result, and test cost. By studying the choices that the women make in the hypothetical scenarios and comparing the attributes and levels, we can analyze the women’s preference of prenatal testing in China. Results Ninety-two women completed the study. Respondents considered the test procedure as the most important attribute, followed by detection rate, miscarriage rate, wait time for result, and test cost, respectively. The estimated preference weight for the non-invasive procedure was 0.928 (P

The microstructure evolution and mechanical properties of air-hardening steel subjected to different austenitizing annealing treatments were investigated in this study and, especially, the precipitation behavior of the steel was analyzed, as well as the strengthening mechanism of the steel was elucidated on the basis of systematic microstructural characterization. Results reveal that a ferrite + martensite dual-phase structure with about 700 MPa tensile strength and 20% elongation can be obtained by austenitizing the experimental steel in the range of 750∼800 °C; while austenitizing between 850 °C and 950 °C results in granular bainite + lath bainite with about 950 MPa tensile strength and 12% elongation. The experimental steel has the highest strength after austenitizing at 900 °C with lots of nano-scale (Ti, Mo, V)C particles distributed in its matrix. Quantitative calculation results illustrate that the main strengthening factors are grain refinement strengthening, dislocation strengthening and precipitation strengthening. In addition, due to the potential interaction effect between different strengthening factors, a modified strengthening model is proposed to describe the strengthening behavior of the air-hardening steel when it is heat-treated in the two-phase region.

The flow behavior of a novel Cr-Si alloyed hot stamping steel (Cr-Si steel) at elevated temperature was investigated via isothermal compression tests on a Gleeble-3500 thermomechanical simulator with a temperature range of 600 ∼ 900 °C and a strain rate range of 0.1 ∼ 10 s ^−1 . Subsequently, the Arrhenius-type constitutive model, comprising strain compensation, was established in accordance with the friction and adiabatic heating corrected stress-strain curves. Furthermore, the predictability and prediction accuracy of the constitutive model were verified. The results reveal that at a constant strain rate, the flow stress of the Cr-Si steel initially increases as the strain increases before tending to stabilize, owning to the combined effects of work hardening and dynamic recovery. The peak flow stresses decrease as the temperatures increase and the strain rates decrease. The constitutive model can accurately predict the elevated temperature constitutive relationship of the Cr-Si steel during the hot stamping process.

Abstract Background Evidence for the relationship between maternal and perinatal factors and the success of vaginal birth after cesarean section (VBAC) is conflicting. We aimed to systematically analyze published data on maternal and fetal factors for successful VBAC. Methods A comprehensive search of Medline, Embase, and the Cumulative Index to Nursing and Allied Health Literature, from each database’s inception to March 16, 2018. Observational studies, identifying women with a trial of labor after one previous low-transverse cesarean section were included. Two reviewers independently abstracted the data. Meta-analysis was performed using the random-effects model. Risk of bias was assessed by the Newcastle-Ottawa Scale. Results We included 94 eligible observational studies (239,006 pregnant women with 163,502 VBAC). Factors were associated with successful VBAC with the following odds ratios (OR;95%CI): age (0.92;0.86–0.98), obesity (0.50;0.39–0.64), diabetes (0.50;0.42–0.60), hypertensive disorders complicating pregnancy (HDCP) (0.54;0.44–0.67), Bishop score (3.77;2.17–6.53), labor induction (0.58;0.50–0.67), macrosomia (0.56;0.50–0.64), white race (1.39;1.26–1.54), previous vaginal birth before cesarean section (3.14;2.62–3.77), previous VBAC (4.71;4.33–5.12), the indications for the previous cesarean section (cephalopelvic disproportion (0.54;0.36–0.80), dystocia or failure to progress (0.54;0.41–0.70), failed induction (0.56;0.37–0.85), and fetal malpresentation (1.66;1.38–2.01)). Adjusted ORs were similar. Conclusions Diabetes, HDCP, Bishop score, labor induction, macrosomia, age, obesity, previous vaginal birth, and the indications for the previous CS should be considered as the factors affecting the success of VBAC.

Abstract Aims/Introduction To summarize the development of the criteria for diagnosing gestational diabetes mellitus (GDM) in China, and investigate how different GDM diagnostic criteria influence the national prevalence of GDM, the national health system and the economic burden of GDM in China. Materials and Methods Retrospectively using data from women undergoing a 2‐h, 75‐g oral glucose tolerance test at 24–28 gestational weeks in the First Affiliated Hospital of Jinan University (Guangzhou, Guangdong, China) from January 2011 to December 2017, the prevalence rate of GDM and its impacts on the national health system were evaluated using different criteria (the 7th edition textbook criteria, National Diabetes Data Group 1979, World Health Organization 1985, European Association for the Study of Diabetes 1996, Japan 2002, American Diabetes Association [ADA] 2011 [International Association of the Diabetes and Pregnancy Study Groups], and National Institute for Heath and Care Excellence 2015). Results The incidence rates of GDM based on the ADA 2011 and National Institute for Heath and Care Excellence 2015 were, respectively, 22.94% (P

Abstract Background Uterine fibroids (UFs) are the most common benign tumors in women. They are likely to cause numerous clinical symptoms, such as pain, menorrhagia, and other obstetric complications in pregnant women. This study aimed to determine the health-related quality of life (HRQoL) during pregnancy with uterine fibroids (UF), thus providing a utility-based case value in pregnant women with UF and understanding of whether HRQoL is associated with clinical outcomes in pregnant women with UFs. Method This study was conducted in a cross-sectional manner. This study was based on questionnaire surveys completed by sequential out- and in-patients and was conducted in a regional university hospital in Guangzhou, China. The EuroQoL five-dimension-five-level (EQ-5D-5 L) questionnaire was used, and demographic data were collected. An electronic record of the clinical outcomes of pregnant women with UF was retrieved from the hospital’s electronic medical record system. The association between UF and HRQoL was evaluated by ordered regression. Results Seven-hundred-sixty-seven pregnant women with a mean age (SD) of 32.7 (4.8) years completed 707 questionnaires. Overall, when comparing the UF with non-UF groups, we detected statistical differences in age, body mass index (BMI), gravidity and abortion times, partner’s smoking and alcoholic habits, advanced maternal age, and uterine scars (p

In this paper, we present the effect of austenitizing temperature on the work hardening behavior of air-hardening steel LH800 by evaluating the influence of austenitizing temperature on microstructure evolution and mechanical properties, using Hollomon, Differential Crussard–Jaoul (DC-J), and Modified C-J (MC-J) work hardening models. The results reveal that with an increase in austenitizing temperature, there is an increase in the percentage of martensite, along with an increase in the strength and hardness of the LH800 steel; on the other hand, there is a decrease in the plasticity. Austenitized at 825 °C, LH800 steel exhibits its highest strength and good plasticity, with a tensile strength of 897 MPa and an elongation of 13.6%. The comparison between the three strain hardening models revealed that the Hollomon model was the finest fit for the experimental data utilized and could illustrate the work hardening behavior of LH800 steel most suitably. This model manifests a two-stage work hardening mechanism; the first stage is related to the plastic deformation of ferrite phase, while the second stage deals with the co-deformation of ferrite and martensite/bainite phase. As austenitizing temperature increases, the work hardening ability of LH800 steel diminishes at each stage, the transition strain decreases, and the plastic deformation of martensite starts earlier.

Abstract Background Gestational diabetes mellitus (GDM) is one of the most common complications during pregnancy, and it has both short- and long-term adverse effects on the health of mothers and fetuses. To investigate the effect of exercise during pregnancy on the occurrence of GDM among normal-weight pregnant women. Methods We searched for studies published between January 1994 and June 2017 that appeared in the Web of Science, Scopus, ClinicalTrials.gov or Cochrane library databases. Randomized controlled trials that investigated the preventive effect of exercise on GDM in normal-weight women were included. Interventions including any confounding factors (e.g., dietary) were excluded. We extracted maternal characteristics, the diagnostic criteria of GDM, and basic information for intervention and obstetric outcomes. The primary outcome was the occurrence of GDM, and the secondary outcomes included gestational weight gain, gestational age at birth, birth weight, and the odds of cesarean section. A meta-analysis was conducted based on calculations of pooled estimates using the random-effects model. Results Eight studies were included in this systematic review and meta-analysis. Exercise during pregnancy was shown to decrease the occurrence of GDM [RR = 0.58, 95% CI (0.37, 0.90), P = 0.01 and RR = 0.60, 95% CI (0.36, 0.98), P = 0.04 based on different diagnosis criteria, respectively] in normal-weight women. Regarding secondary outcomes, exercise during pregnancy can decrease gestational weight gain [MD = − 1.61, 95% CI (− 1.99, − 1.22), P

Abstract Background Appropriate classification of obesity is vital for risk assessment and complication prevention during pregnancy. We aimed to explore which pre-pregnancy BMI cut-offs of obesity, either BMI ≥ 25 kg/m2 as recommended by the WHO for Asians or BMI ≥ 28 kg/m2 as suggested by the Working Group on Obesity in China (WGOC), best predicts the risk of adverse maternal and perinatal outcomes. Methods We retrospectively reviewed 11,494 medical records for live singleton deliveries in a tertiary center in Guangzhou, China, between January 2013 and December 2016. The primary outcomes included maternal obesity prevalence, adverse maternal and perinatal outcomes. Data were analyzed using the Chi-square test, logistic regression, and diagnostics tests. Results Among the study population, 824 (7.2%) were obese according to the WHO criteria for Asian populations, and this would be reduced to 198 (1.7%) based on the criteria of WGOC. Obesity-related adverse maternal and perinatal outcomes were gestational diabetes mellitus, preeclampsia, cesarean section, and large for gestational age (P < 0.05). Compared to the WGOC criterion, the WHO for Asians criterion had a higher Youden index in our assessment of its predictive value in identifying risk of obesity-related adverse outcomes for Chinese pregnant women. Women in the BMI range of 25 to 28 kg/m2 are at high risks for adverse maternal and perinatal outcomes, which were similar to women with BMI ≥ 28 kg/m2. Conclusions A lower pre-pregnancy BMI cutoff at 25 kg/m2 for defining obesity may be appropriate for pregnant women in South China. If WGOC standards are applied to pregnant Chinese populations, a significant proportion of at-risk patients may be missed.

One of the key challenges for transcriptomics-based research is not only the processing of large data but also modeling the complexity of features that are sources of variation across samples, which is required for an accurate statistical analysis. Therefore, our goal is to foster access for wet lab researchers to bioinformatics tools, in order to enhance their ability to explore biological aspects and validate hypotheses with robust analysis. In this context, user-friendly interfaces can enable researchers to apply computational biology methods without requiring bioinformatics expertise. Such bespoke platforms can improve the quality of the findings by allowing the researcher to freely explore the data and test a new hypothesis with independence. Simplicity DiffExpress is a data-driven software platform dedicated to enabling non-bioinformaticians to take ownership of the differential expression analysis (DEA) step in a transcriptomics experiment while presenting the results in a comprehensible layout, which supports an efficient results exploration, information storage, and reproducibility. Simplicity DiffExpress’ key component is the bespoke statistical model validation that guides the user through any necessary alteration in the dataset or model, tackling the challenges behind complex data analysis. The software utilizes edgeR, and it is implemented as part of the SimplicityTM platform, providing a dynamic interface, with well-organized results that are easy to navigate and are shareable. Computational biologists and bioinformaticians can also benefit from its use since the data validation is more informative than the usual DEA resources. Wet-lab collaborators can benefit from receiving their results in an organized interface. Simplicity DiffExpress is freely available for academic use, and it is cloud-based (https://simplicity.nsilico.com/dea).

In order to investigate the law and mechanism of selective oxidation of Quenching and Partitioning (Q&P) steel under different annealing parameters, the sensitivity of alloy elements added in Q&P steel to the annealing parameters was explored. Galvanizing experiments of QP steel were carried out at different annealing temperatures(770 °C and 730 °C) and different holding times(180 s and 300 s). The concentration change of selective oxidation element and the alloying element distribution in the coating were analyzed by Glow Discharge Optical Emission Spectrometer (GDOES), the morphology of surface oxides and inhibition layer were observed by Scanning Electron Microscope (SEM). The results showed that higher annealing temperature(770 °C) and longer annealing time(300 s) could both increase the concentration of Mn and Si on the surface of Q&P steel, improve the oxidation degree of steel surface, thin the inhibition layer, and lead to more leakage plating and deterioration of surface coating quality. The Mn depth profiles showing a parabolic trend and reaching its maximum value at about 20 nm below the surface, while the concentration of Si gradually decreases from the surface to the interior. The selective oxidation of Si and Mn are more sensitive to the annealing temperature than the annealing time.

Metal-organic cages (MOCs) are an emerging class of porous materials with promising applications. However, controlling the configuration of the cage packing, which can influence the overall porosity of the materials, remains a difficulty, as many factors can influence the cage assembly and stacking. Herein, we report a solvent strategy to fine-tune the packing configuration of a bilayer MOC, a small triangular prism cage (six Cu ions act as vertices, three nitrate ions act as pillars, and six nitrate ions act as caps) incorporated into a large triangular prism cage (another six Cu ions act as vertices, a couple of oxygen atoms act as pillars and six ligands (L1: 3,5-bis(pyridine-3-yl)-4H-1,2,4-triazole) act as a jointed cap) by the coordination between the triazole nitrogen from L1 and the inner vertex Cu ions. The involved solvents water, acetonitrile (MeCN) and N,N'-dimethylformamide (DMF) form hydrogen bonds with this bilayer MOC, resulting in three different types of packing associated with systemically tuned porosity (NTU-93: 12.2%, NTU-94: 19.3%, and NTU-95: 42.1%). Gas adsorption and breakthrough tests demonstrate that NTU-95 has potential ability for C2H2/C2H4 separation. This work not only shows a case of finely tuned packing of coordination cages, but also provides a powerful tool that may be extended to other cage families. [ABSTRACT FROM AUTHOR]