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PurposeCadmium (Cd), lead (Pb), and mercury (Hg) have been shown to exhibit endocrine disrupting properties. their effects on women’s reproductive health, however, remain elusive. Here, we investigated associations between blood concentrations of single of Pb, Cd, Hg, and their mixture and infertility and long-term amenorrhea in women of reproductive age using the US National Health and Nutrition Examination Survey (NHANES) 2013-2018 cross-sectional survey.MethodsA total of 1,990 women were included for the analysis of infertility and 1,919 women for long-term amenorrhea. The methods of log-transformation and quarterization were used to analyze blood heavy metal concentrations. Statistical differences in the covariates between the outcome groups were evaluated using a chi-squared test for categorical variables and a t-test for continuous variables. Multiple logistic regression models were used to examine the associations.ResultsThe blood concentrations of Pb and heavy metal mixtures were significantly higher in ever-infertile women than pregnant women, but the concentrations of Cd and Hg were comparable. Multiple logistic regression analysis revealed that after the full adjustment, there was a significant and dose-dependent positive association between blood Pb concentrations and women’s historical infertility, a negative association between Cd and women’s long-term amenorrhea, and no associations between Hg and heavy metal mixture and women’s infertility or long-term amenorrhea.ConclusionsOur study demonstrates that exposure to heavy metals exhibit differential associations with women’s infertility and long-term amenorrhea.Disclosure summaryThe authors declare no conflict of interest.

In the literature, a lot of work focused on studying intermittent control problems via feedback control strategy. No study on the intermittent control problems via sliding mode control method has been reported so far. This paper studies the problem of fast synchronization between two complex dynamical networks via aperiodically intermittent control and sliding mode control. In order to achieve fast synchronization of complex dynamical networks by using aperiodically intermittent sliding mode controller, new differential inequalities are derived firstly. After that, some sufficient finite-time synchronization criteria and finite-time achieving slide mode surface are obtained based on finite-time stability theory, aperiodically intermittent sliding mode control technique and constructing Lyapunov function. Finally, an example is provided to verify the effectiveness of the proposed theoretical methods.

BackgroundExposure of aspirin has been associated with reduced risk of colorectal cancer (CRC) incidence, but aspirin use in relation to CRC patients’ mortality remains undetermined. It is necessary to quantify the association between aspirin use and CRC mortality.MethodsTwo authors independently searched the electronic databases (PubMed, Embase, and the Cochrane Library) from 1947 through April 25, 2020. All observational studies assessing the association between different timing of aspirin use and CRC mortality were included. The effect size on study outcomes was calculated using random-effect model and presented as risk ratio (RR) with 95% confidence interval (CI). Heterogeneity, publication bias, and quality of included studies were also assessed.ResultsA total of 34 studies were included in this systematic review and meta-analysis. Prediagnosis aspirin use was not associated with CRC-specific mortality (RR = 0.91, 95% CI = 0.79 to 1.05) and all-cause mortality (RR = 0.87, 95% CI = 0.57 to 1.31). A statistically significant association between continued aspirin use and improvement in both CRC-specific mortality (RR = 0.76, 95% CI = 0.70 to 0.81) and all-cause mortality (RR = 0.83, 95% CI = 0.74 to 0.93) was observed. Postdiagnosis use of aspirin was associated only with reduced all-cause mortality (RR = 0.80, 95% CI = 0.69 to 0.94).ConclusionsContinued aspirin use before and after CRC diagnosis has the most advantage regarding the improvement of CRC mortality. Nevertheless, further prospective trials and mechanistic studies are highly warranted.

BACKGROUND AND AIM Endoscopic examination of gastric atrophy has been developed to determine the extent of atrophy by identifying the atrophic border of gastric mucosa, but its value in predicting the risk of developing gastric neoplasms is not quantified. Thus, this systematic review and meta-analysis aim to assess the incidence risk of gastric neoplasms on the basis of endoscopic grading of gastric atrophy. METHODS Two authors independently searched the electronic databases (PubMed, Embase, and the Cochrane Library) from inception through December 31, 2019, without language restriction. The effect size on study outcomes is calculated using random-effects model and presented as risk ratio (RR) with 95% confidence interval (CI). Heterogeneity, publication bias, and quality of included studies were also assessed. RESULTS Fourteen retrospective studies are identified to perform systematic review and meta-analysis, 11 were cohort studies, and three were cross-sectional research. The pooled RR for developing gastric neoplasms is 3.89 (95% CI 2.92-5.17) among general patients with severe endoscopic atrophy. For patients who underwent endoscopic resection for early gastric neoplasms, nearly two times increased risk of synchronous or metachronous neoplasms is pooled (RR = 1.96, 95% CI 1.39-2.75). In terms of the type of endoscopic atrophy, patients with open-type endoscopic atrophy have a higher risk of gastric cancer development (RR 8.02; 95% CI 2.39-26.88) than those with close type. [Correction added on 22 December 2020, after first online publication: '(RR = 7.27; 95% CI 1.64-32.33)' has been corrected to '(RR 8.02; 95% CI 2.39-26.88)'] CONCLUSIONS: Grading endoscopic atrophy according to the Kimura-Takemoto classification can assess the risk of gastric neoplasia development. Patients with severe or open-type endoscopic gastric atrophy at baseline should undergo rigorous surveillance to early detect premalignant lesions and cancer.

The fast synchronization problem for a class of complex dynamical networks with time varying delay by means of periodically intermittent control is studied. Based on the finite-time stability theory and periodically intermittent control technique, some sufficient synchronization criteria are obtained to guarantee the fast synchronization. Furthermore, the essential condition for guaranteeing periodically intermittent control realized in finite time is given in this paper. Finally, two examples are illustrated to verify the proposed theoretical results. HighlightsFast synchronization between two complex networks is studied.Two types of periodically intermittent controller to guarantee the finite-time synchronization are obtained.A necessary condition of fast synchronization for periodically intermittent control is given.Numerical simulations are given to show the effectiveness of theoretical results.

Chemical looping technology is a promising pathway to realize a clean production of value-added chemicals with less energy penalty. Its core concept, utilizing heat storage in the cycled solid materials to maintain an efficient operation, needs further confirmation. Here, a combined thermal management method is firstly proposed to achieve an autothermal operation for chemical looping system. New dual fast fluidized bed reactors with optimal reaction temperatures are designed to match the redox reaction rates, while heat integration and exergy cost assessment are conducted to locate the source of thermodynamic irreversibility and interpret the cost formation process. The heat transfer between high temperature exhaust gases and low temperature inlet streams contributes to the main thermodynamic irreversibility and exergy cost. The external energy demand for system gets a maximum 62.37% decrement, the exergy efficiency shows a maximum 9.00% increment and the unit exergy cost for oxygen production gains a maximum 42.18% decrement.

This paper, we propose a routing algorithm in FQ n with large number of faulty nodes under assumption that FQ n is local k-sub-folded-hypercube-connectivity. Based on the algorithm, at least K = min(D k (u), D k (v)) disjoint paths can be found, and each has the length bounded by (d(U k , V k ) + 3)2k. u and v are the source and destination respectively. D k (u) and D k (v) represent the number of non-faulty neighbors of U and V respectively (not considering the internal non-faulty neighbors of U and V in U k and V k ). d(U k , V k ) stands for the distance between two basic k-sub-folded-hypercube U k and V k . This routing algorithm is distributed and local-information-based that each node in FQ n knows only its neighbors' status but no global information is required. So it has strong sense and application in real life.