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The Early Cretaceous Shangzhuang Fe-Ti oxide-bearing layered mafic intrusion in the Yanshan Belt northeast of Beijing is coeval with the giant Late Mesozoic igneous province in the eastern part of the North China Craton (NCC). This magmatic event was associated with lithospheric thinning and thus the igneous rocks have been used to characterize the nature of the Mesozoic mantle beneath the NCC. The Shangzhuang mafic pluton intruded a large granodioritic complex and crystallized at ~ 850–872°C at a depth of 13–14 km. It is composed, from the base upward, of troctolite, Fe-Ti oxide-bearing gabbronorite and gabbro. Rocks from this intrusion have low initial 87 Sr/ 86 Sr ratios (0.7053–0.7058), negative initial ε Nd values (− 9.4 to − 10.7), highly differentiated LREE and nearly flat HREE patterns indicative of an EMI-like mantle source unaffected by upper crustal contamination. The occurrence of Fe-Ti oxide ore layers, magnetite-ilmenite exsolution lamellae in hornblende and high TiO 2 contents of the silicate rocks indicate that they formed from Fe- and Ti-rich ferrobasaltic magmas, which may have been generated by addition of magmas from a deeper mantle source. The presence of orthopyroxene, high-Mg ilmenite (up to 8.5 wt %), hornblende, biotite and high oxygen fugacities calculated from coexisting titanomagnetite-ilmenite pairs can be explained by derivation from an enriched EMI-type mantle modified by fluids from a subducted slab and mixed with asthenospheric or deeper-mantle materials in an extensional setting. Exposure of the complex occurred during large-scale uplift (at least 13 km) and exhumation of the Yanshan orogenic belt in the Early Cretaceous. Chemical metasomatism triggered by water and enhanced by heat from a deep magma source may have played an important role in removing the ancient cratonic root, generating partial melting of the lithospheric mantle and producing coeval magmatic activity in the Mesozoic eastern NCC. [ABSTRACT FROM AUTHOR]

Human immunodeficiency virus (HIV) screening assays have improved from single-antigen detection to detection of antigen–antibody combinations. However, concerns have been raised over the potential for false-positive results in antigen–antibody combination assays. The present study investigated the clinical effectiveness of HIV antigen/antibody (HIV Ag/Ab) combination screening by chemiluminescence microparticle immunoassay (CMIA) in over 88,000 samples from an HIV low-prevalence area of Beijing, China. The HIV Ag/Ab CMIA screening results were consistent with those obtained by Western blot and HIV-RNA testing, and had an accuracy of 99.74% (Kappa index = 0.98). False-positive results were more common for women affected by clinical interfering factors (e.g., kidney disease, tumors) than for men (80.95% vs. 15.09%, P < 0.001). When CMIA signal-to-cutoff ratio (S/CO) was 11.26, the sensitivity and specificity were highest (100%, 99.43%), and the area under the ROC curve (AUC) was 0.998. Specimens that were negative by CMIA (S/CO <1) were all negative by HIV-RNA testing. These results indicate that HIV Ag/Ab CMIA has a good clinical performance; however, some clinical interfering factors should be considered in HIV low-prevalence areas for their potential to skew testing results. [ABSTRACT FROM AUTHOR]

Background: Late rescue intracytoplasmic sperm injection (r-ICSI) has not been widely accepted as an alternative solution for unexpected total fertilisation failure (TFF) after in vitro fertilisation (IVF), due to the time-dependent in vitro deterioration of oocyte quality and endometrial growth not being synchronised with embryo development. This study aimed to evaluate the safety profile and effectiveness of freeze-all blastocyst transfer in combination with late r-ICSI. Methods: This was a retrospective cohort study carried out at the Reproductive Centre of Peking University Third Hospital, Beijing, China. All participants received treatment between 2009 and 2019. 2,270 patients in the aggregate encountered unexpected TFF during 149,054 cycles of IVF and adopted a late r-ICSI procedure. Among these patients, 263 women did not have cleavage-stage embryos available for evaluation. The remaining patients were grouped according to different embryo transfer (ET) strategies (926 women in Group 1 underwent fresh ET, 365 women in Group 2 underwent freeze-all ET, 716 women in Group 3 experienced blastulation failure). Patients received different ET strategies after r-ICSI, with the main outcome measures included live birth rate (LBR), cumulative live birth rate (cLBR), and conservative cLBR. Results: TFF occurred in 7.4% of all IVF cycles. Group 1 tended to be older at oocyte retrieval, with more infertile years, higher follicle-stimulating hormone (FSH) levels, higher gonadotropin consumption, and fewer oocytes retrieved. Group 2 exhibited considerably better LBRs following the first ET cycle (37.53% vs. 4.64%) and cLBRs (52.60% vs. 8.21%). After adjustment for covariates using binary logistic regression analyses, Group 2 still showed better obstetric performance in LBRs [OR:11.77, 95% CI (8.42–16.45)], cLBRs (OR:11.29, 95% CI (7.84–16.27)], and conservative cLBRs (OR:2.55, 95% CI (1.83–3.55)]. Additionally, the two groups showed similar miscarriage rates, whilst no new-borns with malformations or congenital diseases were reported. Conclusions: Freeze-all blastocyst stage ET serves as an optimal strategy to support late r-ICSI. However, for women with limited oocytes available for r-ICSI use, weighing the benefits against the costs of the procedure might be prudent before implementing in vitro blastulation. [ABSTRACT FROM AUTHOR]

Abstract: Background: The primary infection of Toxoplasma gondii (TOX), rubella virus (RV), cytomegalovirus (CMV), or herpes simplex virus (HSV), abbreviated as TORCH, remains a major problem in the pregnant women in China today. Methods: We analyzed the performance of a novel chemiluminesent immunoassay (CLIA) for anti-TORCH IgM and IgG detection then analyzed the prevalence of TORCH infection among 4692 women at childbearing age in Beijing, China. Results: The functional sensitivity of detecting anti-TOX IgM, anti-RV IgM, anti-CMV IgM and anti-HSV (types 1 and 2) IgM were 1.4, 3.2, 1.0 AU/ml and 0.5 index, respectively. The within-assay and the total CVs were both <10%, and recoveries of these assays ranged from 90–110%. High concentration of hemoglobin, lipids and bilirubin in sample did not affect the results. The infective rate of TORCH was 17.2%, with the highest positive rate of anti-HSV IgM. Within anti-TORCH IgG, anti-CMV IgG had the highest infective rate, 92.5%. Conclusions: The infective rate of TORCH was fairly high among women before pregnancy or in the early period of pregnancy in Beijing. Entirely new approaches to prevention and treatment of congenital TORCH infection are necessary. [Copyright &y& Elsevier]

Urban green spaces (UGSs) play a critical role in human thermal comfort, energy consumption and urban ecology. Although the heat mitigation capability of UGSs has been frequently reported, many of the current understandings are based on short-term observations, and the long-term temporal dynamics of UGS cooling effects are still lacking. This gap may cause over- or underestimation and largely ignores how the cooling effects change with climate change and urban growth. Accordingly, we used Landsat-based time series data to analyze the changes in permanent UGS greenness, surface-cooling effects and their biophysical responses in Beijing in the past 40 years (1984–2020). The results demonstrate segmented changes in UGS surface cooling that were mainly linked to the responses of canopy transpiration and albedo to vegetation conditions. During a rapid greening of UGSs in the recent two decades, transpiration cooling dominated albedo-induced warming to provide a discernable cooling enhancement. In addition, such enhancement showed seasonal differences ranging from less than 1 °C to more than 2 °C, and the most evident enhancement occurred on summer days (~2.4 °C) when vegetation is most needed to provide cooling. The highlighted dynamics of UGSs help urban planners better balance the maintenance costs and the environmental gains for UGS management. [ABSTRACT FROM AUTHOR]