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Fluoroquinolone antibiotics are pseudo-persistence in aquatic environments as emerging contaminants. In this study, the Shitoukoumen Reservoir and its four inflow rivers were selected as a typical river-reservoir system. The factors, including river input, rainfall, flow regulation, population, antibiotic half-life, and antibiotic emission path were investigated to find out the reasons for antibiotic variations in the river-reservoir system during the reservoir discharge and filling periods. The results showed that ofloxacin was the most prevalent antibiotic in both the reservoir and inflow-river water, with median concentrations of 18.6 ± 2.4 and 39.7 ± 6.2 ng L−1, respectively. The concentrations of enrofloxacin, norfloxacin, and ofloxacin in the reservoir fluctuated during the reservoir discharge and filling periods. Enrofloxacin was only detected in the reservoir during the discharge period due to its input from the inflow rivers. Artificial reservoir discharge decreased the dissolved concentrations of norfloxacin and ofloxacin in the reservoir, whereas reservoir filling increased their accumulation. The Shuangyang, Yinma, and Chalu Rivers contributed relatively high individual antibiotic mass loads to the reservoir, ranging from 66.7% to 100%. Antibiotic-containing waste runoff during rainfall events increased input contributions of antibiotics from the Shuangyang and Chalu Rivers. The risk assessments indicated that norfloxacin posed a high risk to the most sensitive algae and therefore required greater attention. The study provides a comprehensive insight into fluoroquinolone antibiotic residues in the river-reservoir system during the periods of reservoir discharge and filling, and is of importance for their future monitoring and management. [ABSTRACT FROM AUTHOR]

Venting system is of significance in meeting the high-quality requirements of both injection mold and plastic products. However, the G-code generation for venting system still depends on its geometric features, hindering the realization of CAD/CAM integration for venting system generation. We propose a novel and effective CAD/CAM integration approach to output the G-code of venting system without generating the vent channel geometry. The approach consists of three key modules, viz. discrete vent centerline, generate tool path points, and output G-code. By using an algorithm governed by a bow height threshold, the vent centerline is discretized into a series of points. Based on these discrete points, three categories of points: critical tool path points, safety points, and starting (ending) anchor points, are generated to constitute the tool path points. The third module outputs the G-code according to the final tool path points and verifies the accuracy. A prototype system is also developed to improve the quality and efficiency of venting system design. Finally, a case study is provided to validate the proposed approach. [ABSTRACT FROM AUTHOR]

Female sex workers (FSWs) are considered a high-risk group for sexually transmitted infections (STIs). However, limited data exist on the prevalence and trends of HIV, syphilis and HCV among FSWs in the Sino-Vietnam border area. To determine the prevalence, trends and correlates of STIs among Chinese local FSWs (CL-FSWs) and cross-border migrant FSWs (CM-FSWs), we conducted consecutive cross-sectional surveys from 2016 to 2021, recruiting 7747 CL-FSWs and 932 CM-FSWs. The overall HIV, syphilis and HCV prevalence declined from 1.0%, 8.8% and 1.7% to 0.1%, 0.9% and 0.3%, respectively. There was no significant downward trend in the overall HIV and syphilis prevalence. However, HCV prevalence showed a decreasing trend among CL-FSWs. CM-FSWs had higher HIV prevalence (2.5% vs. 0.6%). Similarities and differences in STIs-related factors existed between CM-FSWs and CL-FSWs. For instance, receiving HIV-related services in the last year reduced the risk of HIV infection (for CM-FSWs: aOR = 0.234, 95% CI: 0.055–0.993; for CL-FSWs: aOR = 0.182, 95% CI: 0.058–0.567). Serving male clients at least 50 years old increased the risk of syphilis infection (for CM-FSWs: aOR = 4.277, 95% CI: 1.535–11.917; for CL-FSWs: aOR = 1.404, 95% CI: 1.087–1.815). Moreover, CM-FSWs with past-year STIs history had a higher risk of HIV (aOR = 34.976, 95% CI: 5.338–229.176) and HCV infection (aOR = 17.649, 95% CI: 1.846–168.846), both of which were associated with multiple factors in CL-FSWs. It is therefore necessary to develop effective, accessible, high-quality and targeted interventions for CM-FSWs and CL-FSWs. [ABSTRACT FROM AUTHOR]

In order to solve the defect that the intrinsic frequency ω0 of the diamagnetic levitation electromagnetic vibration energy harvester cannot be adjusted, a pulling magnet with downward attraction to the floating magnet is added below the floating magnet of the original structure. The simulation found multiple ω0 exist in the structure with the pulling magnet, and the relationship between ω0 and the vertical distance LL from the lifting magnet's lower surface to the floating magnet's upper surface is determined. It is found that ω0 can be varied from 2.36 to 12.3 Hz by adjusting LL. The dynamic characteristics of the floating magnet is studied to obtain its amplitude-frequency curve. The output performance of the energy harvester at different ω0 is calculated and the simulation results are well verified experimentally. The experiments show that the effective voltages can all reach their maximum after arranging the induction coil when the excitation frequency is from 2.2 to 6.1 Hz. The frequency band width for effective voltages greater than 400 mV is made up to 7.6 Hz. The maximum effective voltage of the structure with the pulling magnet is 749 mV, which is 1.98 times larger than the structure without a pulling magnet; the maximum power is 779 µW, which is 7.9 times larger than the structure without a pulling magnet. Experiments show that the structure with the pulling magnet not only significantly broadens the effective bandwidth of the energy harvester, but also significantly improves the output performance of the energy harvester. In addition, the nonlinear characteristics of the system make it possible to obtain good output performance even when the vibration frequency is far from ω0. [ABSTRACT FROM AUTHOR]

Antidepressant medications are widely used by patients with depression or a depressive disorder. In spite of a generally favorable safety profile of selective serotonin reuptake inhibitors or serotonin - norepinephrine reuptake inhibitors (SSRI/SNRI), several cases of a possible connection between SSRI/SNRI and hyponatremia have been reported. To describe the clinical characteristics of patients with hyponatremia after SSRI/SNRI exposure, and to examine the association between SSRI/SNRI exposure and the presence of hyponatremia in a Chinese population. A retrospective single-center case series study. We performed a retrospective evaluation of inpatients with SSRI/SNRI-induced hyponatremia from a single institution in China between 2018 and 2020. Clinical data were obtained through review of medical records. Patients who met the initial inclusion criteria but did not develop hyponatremia acted as controls. The study was approved by the Clinical Research Ethics Board of Beijing Hospital (Beijing, P.R. China). We identified 26 patients with SSRI/SNRI-induced hyponatremia. The incidence rate of hyponatremia was 1.34% (26/1937) in the study population. The mean age at diagnosis was 72.58 (±12.84) years, with a male: female ratio of 1:1.42. The duration between SSRI/SNRI exposure and the onset of hyponatremia was 7.65 (±4.88) days. The minimum serum sodium level was 2328.23 (±107.25) mg/dL in the study group. Seventeen patients (65.38%) received sodium supplements. Four patients (15.38%) switched to another antidepressant. Fifteen patients (57.69%) recovered by the time of discharge. There were significant differences in serum potassium, serum magnesium and serum creatinine level between the two groups (p < 0.05). The rate of use of sertraline was significantly higher in the study group compared with the control group (p < 0.05). This pattern was not found in other SSRI/SNRI (p > 0.05). The results of our study show that SSRI/SNRI exposure, in addition to hyponatremia, may also affect the level of serum potassium, serum magnesium and serum creatinine. A history of hyponatremia and exposure to SSRI/SNRI may be potential risk factors for the development of hyponatremia. Future prospective studies are needed to validate these findings. [ABSTRACT FROM AUTHOR]

Objective: To investigate the association of single nucleotide polymorphisms (SNPs) of various genes known to influence mean daily warfarin dose (MDWD) in the Han Chinese population. Methods: The study is a systematic review and meta-analysis. Selected studies retrieved by searching Pubmed, Embase (Ovid), Medline, CNKI, Wanfang data, and SinoMed (from their inception to 31 August 2022) for the cohort studies assessing genetic variations that may possibly influence MDWD in Chinese patients were included. Result: A total of 46 studies including a total of 10,102 Han Chinese adult patients were finally included in the meta-analysis. The impact of 20 single nucleotide polymorphisms (SNPs) in 8 genes on MDWD was analyzed. The significant impact of some of these SNPs on MDWD requirements was demonstrated. Patients with CYP4F2 rs2108622 TT, EPHX1 rs2260863 GC, or NQO1 rs1800566 TT genotype required more than 10% higher MDWD. Furthermore, patients with ABCB1 rs2032582 GT or GG, or CALU rs2290228 TT genotype required more than 10% lower MDWD. Subgroup analysis showed that patients with EPHX1 rs2260863 GC genotype required 7% lower MDWD after heart valve replacement (HVR). Conclusion: This is the first systematic review and meta-analysis assessing the association between single nucleotide polymorphisms (SNPs) of various genes known to influence MDWD besides CYP2C9 and VKORC1 in the Han Chinese population. CYP4F2 (rs2108622), GGCX (rs12714145), EPHX1 (rs2292566 and rs2260863), ABCB1 (rs2032582), NQO1 (rs1800566), and CALU (rs2290228) SNPs might be moderate factors affecting MDWD requirements. Registered information: PROSPERO International Prospective Register of Systematic Reviews (CRD42022355130). [ABSTRACT FROM AUTHOR]

Oxygen and carbon isotopic compositions of diagenesis? coral samples from NY-1 core at the depth of 22 to 50 m, together with mineral compositions of transitive coral samples of 17 to 18 m at the depth, were meas ured. The data exhibited that when aragonite changed to calcite, its oxygen and carbon isotopic compositions dropped roughly on a linear trend. The linear trend implies that the oscillation pattern of the origin oxygen and carbon isotopic ratios of the aragonite could probably be retained after they diageneticly changed into calcite. Oxygen isotopic stratigraphy for the NY-1 core at the depth between 22 and 50 m was determined according to the δ8O ratios of the calcite coral. The oxygen stratigraphy provided an age of about 289 ka for 45 m of the NY-1 core, which agreed with that by paleomagnetic stratigraphy. [ABSTRACT FROM AUTHOR]

The δO and δD values for meteoric water samples collected from eastern Xizang and western Sichuan and Guizhou show a linear correlation and can be described by the following equation: δD = 8.22δO + 18.99. The isotopic compositions of these meteoric waters also exhibit obvious altitude effect. There have been found negative correlations between δO, δD and the elevation, which are characterized by −δO‰ = 0.0031H(m) + 6.19 and −δD‰ = 0.026H(m) + 30.20. The average δO and δD values for meteoric waters in the areas with an altitude of more than 4,000m above sea level are equal to -18.70 and -137.8‰, respectively. It is evident that the δO and δD values for plateau lake waters depend on their water supply. The δO and δD values for the water in lakes where the evaporation rate is greater than the recharge rate, are approximately three or four times higher than those of supply water, averaging -5.74 and -60.5‰, respectively. The oxygen and hydrogen isotopic compositions of geothermal waters as compared with those of local meteoric waters in adjacent areas show that the latter seems to be the main water-supply source. [ABSTRACT FROM AUTHOR]

42 meteoric water samples were analyzed for their δO and δD values. It can be seen that both δO and δD values vary synchronously with latitude along our investigation-tour route from Guangxi (22.7 NL°) to Heilongjiang (48.8 NL°). Their relationship is presented as follows: δO(‰)=−0.24 NL° + 0.04 and δD(‰)=−1.84 NL° + 6.88. The relationship between δO, δD and altitude in the southeastern part of the Guizhou Plateau is: [ABSTRACT FROM AUTHOR]

The objective of this study was to fabricate and characterize chitosan combined with different amounts of simvastatin-loaded nanoparticles and to investigate their potential for guided bone regeneration in vitro and in vivo. Different SIM-CSN formulations were combined into a chitosan scaffold (SIM-CSNs-S), and the morphology, simvastatin release profile, and effect on cell proliferation and differentiation were investigated. For in vivo experiments, ectopic osteogenesis and the critical-size cranial defect model in SD rats were chosen to evaluate bone regeneration potential. All three SIM-CSNs-S formulations had a porous structure and exhibited sustained simvastatin release. CSNs-S showed excellent degradation and biocompatibility characteristics. The 4 mg SIM-CSNs-S formulation stimulated higher BMSC ALP activity levels, demonstrated significantly earlier collagen enhancement, and led to faster bone regeneration than the other formulations. SIM-CSNs-S should have a significant effect on bone regeneration. Highlights: Simvastatin-loaded nanoparticles of chitosan. The preparing process of Chitosan scaffolds combined with simvastatin loaded is simple, low-cost and environmental friendly. A sustained release of simvastatin. [ABSTRACT FROM AUTHOR]