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STUDY QUESTION Is pre-conception exposure to parabens associated with fecundity in couples of childbearing age? SUMMARY ANSWER Paraben exposure in female partners was associated with reduced couple fecundity and anti-Müllerian hormone (AMH) might be one of the possible mediators. WHAT IS KNOWN ALREADY The reproductive toxicity of parabens, a class of widely used preservatives, has been suggested but evidence regarding their effects on couple fecundity is scarce. STUDY DESIGN, SIZE, DURATION In this couple-based prospective cohort study, a total of 884 pre-conception couples who participated in the Shanghai Birth Cohort between 2013 and 2015 were included. PARTICIPANTS/MATERIALS, SETTING, METHODS Concentrations of six parabens were measured in urine samples collected from couples. Malondialdehyde, C-reactive protein, and AMH were assessed in female partners. The outcomes included couple fecundability (time-to-pregnancy, TTP) and infertility (TTP > 12 menstrual cycles). Partner-specific and couple-based models were applied to estimate the associations. The joint effect of paraben mixture on couple fecundity was estimated by quantile-based g-computation (q-gcomp). Mediation analysis was used to assess the mediating roles of oxidative stress, inflammation and ovarian reserve. MAIN RESULTS AND THE ROLE OF CHANCE A total of 525 couples (59.4%) conceived spontaneously. In the partner-specific model, propyl paraben (PrP), butyl paraben (BuP), and heptyl paraben (HeP) in female partners were associated with reduced fecundability (fecundability odds ratio (95% CI): 0.96 (0.94–0.98) for PrP; 0.90 (0.87–0.94) for BuP; 0.42 (0.28–0.65) for HeP) and increased risk of infertility (rate ratio (95% CI): 1.06 (1.03–1.10) for PrP; 1.14 (1.08–1.21) for BuP; 1.89 (1.26–2.83) for HeP). Similar associations were observed in the couple-based model. AMH played a significant mediation role in the association (average causal mediation effect (95% CI): 0.001 (0.0001–0.003)). Paraben exposure in male partners was not associated with couple fecundity. The joint effect of paraben mixture on couple fecundity was non-significant. LIMITATIONS, REASONS FOR CAUTION Self-reported pregnancy and single urine sample may lead to misclassification. The mediation analysis is limited in that levels of sex hormones were not measured. The inclusion of women with irregular menstrual cycles might affect the results. It is possible that the observed association was due to reverse causation. WIDER IMPLICATIONS OF THE FINDINGS This is the first study to assess the effects of paraben exposure on couple fecundity in Asians. Given the widespread exposure to parabens in couples of childbearing age, the present findings may have important public health implications. STUDY FUNDING/COMPETING INTEREST(S) This study was supported in part by the National Natural Science Foundation of China (41991314), the Shanghai Science and Technology Development Foundation (22YF1426700), the Science and Technology Commission of Shanghai Municipality (21410713500), and the Shanghai Municipal Health Commission (2020CXJQ01). All authors declare no conflict of interest. TRIAL REGISTRATION NUMBER N/A.

Background: An increasing number of studies have reported that prenatal per- and polyfluoroalkyl substances (PFAS) exposure may increase childhood adiposity. However, limited data is available in China, and the overall effects of PFAS mixture remain unclear. Objective: To examine the association of prenatal exposure to individual PFAS and their mixture with childhood adiposity at 7 years of age. Methods: A total of 206 mother-infant pairs were recruited from the Laizhou Wan (Bay) Birth Cohort in China between 2010 and 2013. Ten PFAS were measured in maternal serum. The measurements of fat mass, body fat percentage, body mass index, waist circumference, waist-to-height ratio and overweight/obesity were used to assess adiposity in children aged 7. We fitted logistic regression, linear regression and weighted quantile sum (WQS) regression models to estimate the association of prenatal exposure to individual PFAS and their mixture with childhood adiposity. Results: We found negative associations of perfluoroheptanoic acid (PFHpA) and perfluorooctane sulfonamide (PFOSA) exposure with adiposity measurements in all children. The result from the WQS model consistently revealed that the PFAS mixture was inversely related to adiposity measurements. Each quartile increase of the PFAS mixture was associated with a 1.14 kg decrease (95% CI: −2.27, −0.02) in fat mass and a 2.32% decrease (95% CI: −4.51, −0.14) in body fat. Moreover, significant sex differences were found. PFAS mixture was negatively associated with five adiposity measurements in boys, but positively associated with all adiposity measurements except body fat percentage in girls. PFOSA, PFHpA and perfluorobutanesulfonate (PFBS) with weights >0.300 were the main contributors to the overall effects observed among all children, boys and girls, respectively. Conclusion: This study suggests potential sex-specific associations of prenatal exposure to individual PFAS and their mixture with childhood adiposity, with the observed relationship being negative for boys but positive for girls.

Legacy and emerging per- and polyfluoroalkyl substances (PFAS) have attracted growing attention due to their potential adverse effects on humans. We developed a method to simultaneously determine thirty-three PFAS (legacy PFAS, precursors, and alternatives) in human plasma and serum using solid phase extraction coupled to ultra-performance liquid chromatography-tandem mass spectrometry (SPE-UPLC-MS/MS). The method yielded good linearity (0.995) and excellent limits of detection (LODs) (0.0005~0.012 ng mL

Osteoarthritis (OA) impacted over 5-million people worldwide in 2018, with an incidence second only to diabetes and hypertension. Clinical research has had difficulty in finding methods to treat OA quickly and effectively. More and more researchers have begun to explore the effects of estrogen (ER) on OA.The study intended to conduct a meta-analysis of studies using ER in OA, aiming to confirm the potential value of ER, laying a foundation for follow-up research, and providing new choices for the treatment of OA.The research team performed a literature review searching PubMed for clinical studies on the application of ER for the OA treatment or on the improvement of joint pain that: (1) were published after the year 2000, and (2) had participants who used ER compared to other treatment methods. The research team selected studies for analysis after independent screening by two members of the team, based on inclusion and exclusion criteria and a methodological quality evaluation. The meta-analysis used RevMan V5.3 software.The research team included eight studies with 11 689 participants, with 5776 participants who received ER treatments becoming the intervention group, and with 5913 participants who received other treatments becoming the control group.The outcome measures included the selected studies' results related: (1) to changes in the bone marker, collagen cross-linked C-telopeptide type I (CTX-1); (2) to the levels of bone Gla protein (BGP); (3) to joint-pain relief, and (4) to subjective scores on the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), a visual analogue scale (VAS) for pain, and the Short-Form 36 (SF-36).The meta-analysis found that the CTX-II level was significantly lower (P.0001) and the BGP level was significantly higher (P = .07) in the EG group than the levels in the control group. Similarly, the number of participants with joint pain in the ER group was significantly lower than that of the control group (P = .01), and a significant difference existed between the groups in the subjective scores (P = .02).ER can exert varying degrees of positive effects on OA and can effectively ameliorate the pathological process in OA patients, and it may become an alternative for OA treatment in the future, providing patients with better health and life quality.

Background The analysis of circulating tumor cell-associated white blood cell (CTC-WBC) clusters represented the progress in the liquid biopsy of malignant tumors, however, related research in patients with colorectal cancer is still absent. Methods To explore associations between CTC-WBC clusters and the prognosis of these patients, we conducted an independent cohort of 329 colorectal cancer patients after curative intent surgery and pre-operative CTC detection in Nanfang Hospital, Southern Medical University, Guangzhou, China between January 1, 2017, and September 31, 2019. The primary cohort referred to patients with CTC-WBC clusters positive. The control cohort was defined as those with exclusively CTCs positive. CTCs were enriched and distinguished by The CanPatrol™ system (SurExam, China). The Kaplan–Meier curve was used to compare the progressive-free survival (PFS) and overall survival (OS) between two groups. The COX regression model was used to assess the predictive value of CTC-WBC clusters. Results Sixty three patients presented CTC-WBC clusters positive (CTC-WBC group) and 266 patients showed solely CTCs (CTC group). The number of CTCs was significantly different between two groups (P P = 0.011), while not for OS. The multivariate model further suggested that the CTC-WBC clusters (Hazard Ratio = 1.89, 95% Confidence Interval 1.02–3.51, P = 0.042) was an independent predictor for the PFS of in post-operation CRC patients. Conclusion The CTC-WBC cluster is significantly associated with recurrence after operation in CRC patients. This finding facilitates the evaluation of this indicator in tumor progression.

Objective：In order to treat and improve recurrent patellar dislocation (RPD), autologous partial peroneal long tendon (PLT) or autologous partial semitendinosus tendon (ST) were taken to reconstruct the medial patellofemoral ligament (MPFL) respectively. The postoperative effects of the two methods were compared.Method:Patients with RPD in the Department of orthopedics of the Sixth Affiliated Hospital of Xinjiang Medical University were selected, and underwent MPFL reconstruction from February 2018 to February 2021. There were 65 cases, including 20 male patients and 45 female patients. The grafts were autologous PLT or ST, including 32 cases in PLT group and 33 cases in ST group. The evaluation indexes include: postoperative complications: patellar fracture, patellar subluxation, knee pain, knee stiffness, lower limb skin paresthesia, patellar tilt angle, patellar concentration angle, Kujala score and kofoed score of ankle. The functional improvement and complications of patella and knee joint before and after operation were compared, and the curative effect of PLT and ST reconstruction of MPFL was analyzed.Results：The follow-up time was 12-15 months. There were 7 cases of knee pain and 5 cases of knee stiffness in PLT group and 5 cases of knee pain and 3 cases of knee stiffness in ST group. There was no significant difference in postoperative pain and stiffness between the two groups (P > 0.05). There were 18 cases of infrapatellar branch of saphenous nerve (IPBSN) injury in ST group, but no IPBSN injury was found in PLT group (P < 0.05). The IPBSN injury in ST group was positively correlated with the incision length of tendon extraction (P < 0.05). In the last follow-up, there was no significant difference in patellar tilt angle, patellar convergence angle and Kujala score between the two groups (P > 0.05). The kofoed score of ankle joint in both groups was excellent.Conclusions：Autologous PLT and ST reconstruction of MPFL can effectively treat RPD, significantly improve patellar tilt angle and patellar concentration angle, improve Kujala score, improve knee function and clinical symptoms. Both are effective ways to treat RPD, but ST group will lead to IPBSN injury and sensory impairment of anterolateral skin of lower leg.

6:2 polyfluoroalkyl phosphate diester (6:2 diPAP) has been demonstrated to disrupt reproductive endocrine functions using experimental studies. However, evidence from humans is not available yet. This cross-sectional study aims to assess the relationship between 6:2 diPAP exposure and the testicular function among adult men. A total of 902 men seeking preconception care were included. Plasma 6:2 diPAP concentrations were determined, while the testicular function was assessed via semen quality and reproductive hormones in serum. The association was assessed by multiple linear regression. Stratified analyses by age and body mass index (BMI) were conducted to assess the potential effect modification by these two variables. Regression analyses revealed that 6:2 diPAP exposure was significantly inversely associated with androgens [i.e., total testosterone (TT) and free androgen index (FAI)], markers of testosterone production potential [i.e., TT/luteinizing hormone (LH) and FAI/LH], estradiol, and insulin-like factor 3, a biomarker of Leydig cell function. These associations were robust in sensitivity analyses. However, age and BMI did not modify these associations, and no association was observed between 6:2 diPAP and semen quality. Our study suggests that exposure to 6:2 diPAP may inhibit androgen synthesis and impair Leydig cell function in adult men.

The higher norepinephrine (NE) concentration induced by sympathetic nerve hyperactivation participated in pulmonary artery smooth muscle cells (PASMCs) over-proliferation and led to pulmonary vascular remodeling (PVR), which played an important role in pulmonary artery hypertension (PAH). However, the underlying mechanism by which NE induced PASMCs proliferation had not been fully elucidated. In the present study, we found that prazosin, the inhibitor of α

In this paper, a torsion–translational quasi-zero-stiffness (TT QZS) isolator with convex ball–roller mechanisms was proposed to attenuate the torsion and translational vibrations along shaft systems simultaneously. The mathematical model of the isolator was established, based on which the static characteristics of the isolator were analyzed and the quasi-zero-stiffness condition that the design parameters should satisfy was derived as well. Subsequently, the isolator was integrated into a shaft system to study its dynamical performances under excitations of two independent external forces. Unique phenomenon of so-called vibration frequency–interference was observed and elaborated theoretically with harmonic balance method. In addition, the amplitude–frequency characteristics of the two degrees-of-freedom (DOFs) system subjected to two independent harmonic excitations were analyzed by employing numerical simulations. Accordingly, the small-oscillation regions of the system were determined through the jump-down frequencies. Meanwhile, the force transmissibility in the small-amplitude-oscillation region was discussed by taking advantage of semi-analytical solutions and compared with that of the corresponding linear system. The results indicated that the TT QZS isolator has extra low-frequency vibration isolation performance in both torsion and translational DOFs.

Contaminated sites are a main cause of urban soil problems and have led to increasing pollution and public risk in China as a result of the rapid growth of industrial and urban land use. Because land pollution involves extensive multi-source heterogeneous information, identifying the risk of urban soil pollution efficiently and predicting pollution-related events are important for urban environmental management. Knowledge graphs (KGs) have unique advantages in dealing with massive amounts of information. This study attempts to construct a KG of contaminated sites in South China to explore its feasibility and effectiveness in urban soil environmental management. The results demonstrate that KGs have a favorable effect in information retrieval, knowledge reasoning, and visualization. Studied cases in this article demonstrate that the KG model can achieve many functions, including the display of global information of polluted sites, and discovery of regional distribution of characteristic pollutants and main pollutants of specific industries, based on special query syntax. However, this approach is limited by some technical difficulties, such as knowledge mining of natural resources, which must be overcome in future studies to improve the operability of KG technologies.

Phenols are widely used in consumer products and known for their reproductive toxicities. Little is known regarding the environmental exposure to phenols in couples prior to conception, a key period affecting fertility. We measured the urinary concentrations of six parabens and seven bisphenols in 903 pre-conception couples in China. We investigated the occurrence, distribution, source and health risk of phenols in husbands and wives separately, and the correlation and difference in phenol concentrations between couples. Similar distribution profiles of urinary phenols were observed between females and males. Methyl 4-hydroxybenzoate (MeP) and bisphenol A (BPA) were the predominant compounds. The level of urinary phenols in our population was mostly lower than the global levels. Exposure to phenols was linked to processed food and personal care products. The correlations between phenols in males and females were moderate (0.218-0.686), while the correlation in phenols between husband and wife was low (0.009-0.215). Female had a significantly higher urinary phenol levels than male (P0.05). Urinary phenols in couples were associated with family income, type of drinking water and frequency of household cleaning. Household factors accounted for ≤1.5% of variance in phenol levels between couples, suggesting that individual variations may be the major factor. Risk assessment showed that exposure to phenols posed a low hazard to 17.5% of the couples in our population. Our findings provide important evidence of environmental exposure to phenols in couples of child-bearing age.

Multiple studies have examined the relationship between PFAS and semen quality, but none has explored the associations of PFAS mixture that includes emerging alternatives and branched isomers.22 PFAS, including 10 linear legacy PFAS, 7 branched isomers, 3 short chain alternatives and 2 components of F53B [e.g., 6:2 chlorinated polyfluorinated ether sulfonate (Cl-PFESA)] were quantified in blood plasma among 740 healthy men. Five semen quality parameters (i.e., volume, count, concentration, total motility and progressive rate) were assessed. Multiple linear regression and three multiple pollutant models (i.e., adaptive elastic net regression, quantile based g-computation, and XGBoost method) were used to assess the associations of individual PFAS and PFAS mixture with semen quality and the potential interactive effects among congeners.After adjusting for selected confounders, perfluorobutane sulfonate (PFBS) and perfluorohexane sulfonate (PFHxS) presented significant and negative associations with sperm count [βIn the current cross-sectional study, we found that two emerging PFAS replacements (i.e., 6:2 Cl-PFESA and PFBS) and PFHxS exposure were associated with reduced semen concentration, total sperm count and motility in men. Meanwhile, significant positive associations between PFHpS and sperm count and concentration were also observed. But there were no consistent associations between PFAS mixture, branched isomers and semen quality.

A parallel nonlinear energy sink (NES) is proposed and analyzed. The parallel NES is composed of a vibro-impact (VI) NES and a cubic NES. The dynamical equation is given, and the essential analytical investigation is carried out to deal with the cubic nonlinearity and impact nonlinearity. Multiple time-scale expansion is introduced, and the zeroth order is derived to give a rough outline of the system. The underlying Hamilton dynamic equation is given, and then the optimal stiffness is expressed. The clearance is regarded as a critical factor for the VI. Based on the periodical impact treatment by analytical investigation, the relationships of the cubic stiffness, the clearance, and the zeroth-order attenuation amplitude of the linear primary oscillator (LPO) are obtained. A cubic NES under the optimal condition is compared with the parallel NES. Harmonic signals, harmonic signals with noises, and the excitation generated by a second-order filter are considered as the potential excitation forces on the system. The targeted energy transfer (TET) in the designed parallel NES is shown to be more efficient.

In this work, trap passivation can be enhanced by introducing the controlled tetraethyl orthosilicate (TEOS) additive into the perovskite precursor. The effect of different concentrations of TEOS additive on interfacial modification and carrier recombination process has been investigated systematically. Silicon dioxide (SiO2), the product of TEOS additive, can precipitate at the grain boundary after the formation of perovskite film, resulting in trap passivation at perovskite interface. The recombination kinetics manifests that a small amount of TEOS additive can significantly prolong carrier lifetime, due to the reduction of trap-states in the perovskite interface, which are supposed to be the carrier recombination centers. Using a typical planar structure of the cells prepared under fully open air condition, the steady-state efficiency of our best-performing devices has improved from 15.96 to 18.38%.

A novel method based on time-dependent stochastic orthogonal bases for stochastic response surface approximation is proposed to overcome the problem of significant errors in the utilization of the generalized polynomial chaos (GPC) method that approximates the stochastic response by orthogonal polynomials. The accuracy and effectiveness of the method are illustrated by different numerical examples including both linear and nonlinear problems. The results indicate that the proposed method modifies the stochastic bases adaptively, and has a better approximation for the probability density function in contrast to the GPC method.

Hybrid CH3NH3PbX3 (where X = I, Br, Cl) is a hybrid organic-inorganic material with a perovskite structure and is sensitive to moisture, oxygen, UV light, light soaking, heat, electric field, etc. Among all these factors, thermal stability is one of the most challenging concerns affecting device stability, since it is hard to avoid a temperature increase during operation, leading to phase transition from tetragonal to cubic. Furthermore, the mechanism of phase change has been largely unexplored. In this work, we propose doping 2.5% SnCl2 into CH3NH3PbI3 in order to enhance its phase transition temperature from 57 °C to 90 °C, demonstrating amazing heating tolerance. The enhancement can be attributed to slightly modified interaction with the ions in the provskite crystal network. Surprisingly, upon comparison to their undoped counterparts, the samples with low concentration doping yields stronger intensity of light absorption and the efficient electron extraction. Herein, our results can provide an important step toward material engineering to address some of the key challenges facing perovskite based solar cells and other optoelectronic devices.

Based on patent counts and patent values, this study presents quantitative and qualitative measurements of the comparative technological advantages between renewable and fossil-fuel fields of energy production across China, the U.S., Japan and European countries. The results show that the field of renewable energy exhibits greater technological potential and is progressing at a faster pace than is that of fossil-fuel energy. China is following most other countries by increasing investments in developing renewable energy technology, contributing to a global increase of the technological advantages of renewable energy relative to those of fossil-fuel energy. Although China is technologically disadvantaged in the fields of energy production, particularly in the qualitative aspect reflected by patent values, the technological gap between China and developed areas is shrinking. Compared with a regular mobilization of the technological advantages between different areas in the field of fossil-fuel energy, a drastic change of the technological advantage in the international dimension indicates intense competition in renewable energy technology. The results of this study provide a new reference for predicting not only the market potential of energy technology but also, the global energy technology patterns in the near future.

Shape memory alloys (SMA) have long been explored as a semi-passive approach to mechanical energy dissipation particularly, but not exclusively, for application to vibration control. More recently, the integration of SMAs in composite materials has opened the opportunity to synthesize tunable composite structures exhibiting significantly enhanced energy dissipation characteristics and a certain degree of adaptability to different operating conditions. Despite the significant progress in the development and manufacturing of SMAs over the past several decades, the cost of common Ni-based alloys has remained an important factor hindering their widespread engineering application. The long-term goal of this research effort is to model, design, and fabricate shape-memory-alloy (SMA) meta-composites employing lower volume fractions of a more affordable Cu-based alloy, while still enabling enhanced and tunable dynamic properties. This paper summarizes recent progress in the development of the meta-composite platform and focuses on aspects involving both numerical modeling and fabrication of SMA materials. On the modeling side, particular emphasis is given to assess the ability to tune the dynamic performance of continuous SMA structures by exploiting the different phases and transformations of the alloy. On the other side, the material development effort focuses on the identification of the optimal chemical composition, mechanical and heat treatment processes. A combination of numerical and experimental results is presented to illustrate capabilities and opportunities presented by this material platform.

Environmental phenols are a typical group of endocrine disrupting compounds (EDCs) and have caused growing concerns upon the potential adverse effects on humans. Urinary concentrations of phenols can be used as valid biomarkers for the assessment of human exposure. A method was developed for the simultaneous determination of eighteen environmental phenols (six parabens, seven bisphenols, four benzophenones and triclosan) in human urine using liquid-liquid extraction (LLE) coupled to high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The optimized LLE was time saving and required low volumes of organic solvents. A volume of only 0.2 mL urine sample was extracted and analyzed. The method yielded good linearity (0.9925–0.9994) and satisfactory limit of detection (LOD) (≤0.08 ng mL−1). The relative recoveries ranged between 76.7% and 116% at three spiked levels, with intra- and inter-day precision less than 8.04% and 13.5%, respectively. Our method has been proved to be simple, rapid and sensitive by a comprehensive comparison between methods. This proposed method provides a large-scale biomonitoring tool for exposure assessment of human population to environmental phenols.

Consolidated server racks are quickly becoming the standard infrastructure for engineering, business, medicine, and science. Such servers are still designed much in the way when they were organized as individual, distributed systems. Given that many fields rely on big-data analytics substantially, its cost-effectiveness and performance should be improved, which can be achieved by flexibly allowing resources to be shared across nodes. Here we describe Venice, a family of data-center server architectures that includes a strong communication substrate as a first-class resource. Venice supports a diverse set of resource-joining mechanisms that enables applications to leverage non-local resources efficiently. We have constructed a hardware prototype to better understand the implications of design decisions about system support for resource sharing. We use it to measure the performance of at-scale applications and to explore performance, power, and resource-sharing transparency tradeoffs (i.e., how many programming changes are needed). We analyze these tradeoffs for sharing memory, accelerators, and NICs. We find that reducing/hiding latency is particularly important, the chosen communication channels should match the sharing access patterns of the applications, and of which we can improve performance by exploiting inter-channel collaboration.