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Sport is a male-dominated field where female athletes are relatively marginalized. This article applies the theory of framing to explore how a high-profile female athlete --Li Na-- is trivialized by the coverage of China’s mainstream media. The analysis reveals that stereotypical feminine roles, individualism and collectivism, and nationalism are common aspects regularly emphasized by media to undermine Li Na’s athletic achievement.

Background: Antral follicles consist of an oocyte cumulus complex surrounding by somatic cells, including mural granulosa cells as the inner layer and theca cells as the outsider layer. The communications between oocytes and granulosa cells have been extensively explored in in vitro studies, however, the role of oocyte-derived factor GDF9 on in vivo antral follicle development remains elusive due to lack of an appropriate animal model. Clinically, the phenotype of GDF9 variants needs to be determined. Methods: Whole-exome sequencing (WES) was performed on two unrelated infertile women characterized by an early rise of estradiol level and defect in follicle enlargement. Besides, WES data on 1,039 women undergoing ART treatment were collected. A Gdf9Q308X/S415T mouse model was generated based on the variant found in one of the patients. Results: Two probands with bi-allelic GDF9 variants (GDF9His209GlnfsTer6/S428T, GDF9Q321X/S428T) and eight GDF9S428T heterozygotes with normal ovarian response were identified. In vitro experiments confirmed that these variants caused reduction of GDF9 secretion, and/or alleviation in BMP15 binding. Gdf9Q308X/S415T mouse model was constructed, which recapitulated the phenotypes in probands with abnormal estrogen secretion and defected follicle enlargement. Further experiments in mouse model showed an earlier expression of STAR in small antral follicles and decreased proliferative capacity in large antral follicles. In addition, RNA sequencing of granulosa cells revealed the transcriptomic profiles related to defective follicle enlargement in the Gdf9Q308X/S415T group. One of the downregulated genes, P4HA2 (a collagen related gene), was found to be stimulated by GDF9 protein, which partly explained the phenotype of defective follicle enlargement. Conclusions: GDF9 bi-allelic variants contributed to the defect in antral follicle development. Oocyte itself participated in the regulation of follicle development through GDF9 paracrine effect, highlighting the essential role of oocyte-derived factors on ovarian response. [ABSTRACT FROM AUTHOR]

There is an urgent need for new CO2 adsorbents to overcome the rapidly increasing CO2 pollution. New CuO@UiO-67 composites were prepared by encapsulating CuO nanoparticles (NPs) in the shallow pore channels of UiO-67 through postsynthetic exchange (PSE) to form a core–shell structure. The composites were characterized via TEM, XRD, and BET analyses, and single component adsorption isotherm measurements of CO2, CH4 and N2 were performed at different temperatures. The selectivities of CO2/CH4 and CO2/N2 and the isosteric heats of CO2 adsorption were estimated based on the ideal adsorption solution theory (IAST) and the Clausius–Clapeyron equation, respectively. The highest CO2 uptake of CuO@UiO-67 was achieved at 273 K and 100 kPa with 61.9 cc g−1, which was twice that of parent UiO-67. The significant increase in CO2 uptake was not only due to the introduction of CuO NPs in the pore channel of CuO@UiO-67, but also due to the new open nitrogen sites due to ligand substitution. The adsorption selectivities of CO2/CH4 and CO2/N2 at 298 K and 100 kPa were 9.2 and 54.3, respectively. Furthermore, CuO@UiO-67 could efficiently separate the CO2/N2 mixture under a dynamic flow condition. These excellent properties suggest that the CuO@UiO-67 composite is a promising and efficient CO2 adsorbent material. This study lays a solid foundation for metal oxide-modified MOFs and is a great contribution to the preparation of new adsorbents. [ABSTRACT FROM AUTHOR]

The biological denitrification of low-C/N wastewater is a great challenge in treatment plants due to the lack of microorganisms with heterotrophic nitrification–aerobic denitrification (HN-AD) abilities. In this study, Bacillus sp. L2 was isolated from aeration tank water samples using a nitrification medium and screened for its ability to perform HN-AD in low-C/N wastewater. The strain showed a maximum NH4+-N removal rate of 98.37% under low-C/N conditions. In the presence of a mixed N source, strain L2 was capable of completely removing NH4+-N within 24 h. Furthermore, optimal nitrogen removal conditions for strain L2 were found to be C/N = 9, pH = 9, and sodium acetate as the C source. Under optimal conditions, the strain was able to maintain a high NH4+-N removal rate under 0–3% salinity and an NH4+-N concentration of 200 mg/L or less. The denitrification pathways of strain L2 were NH4+→NH2OH→NO2−(↔NO3−)→NO→N2O→N2 and NH4+→NH2OH→NO→N2O→N2. Furthermore, semi-continuous wastewater treatment was conducted using immobilized technology, which resulted in more than 82% NH4+-N removal after three cycles of reuse. This study demonstrates the great potential of Bacillus sp. L2 in wastewater treatment applications. [ABSTRACT FROM AUTHOR]

The rheological behavior of Mo-12Si-8.5B alloy reinforced by a layered Mo2TiAlC2 phase has been studied at temperatures ranging from 1200°C to 1400°C and strain rates ranging from 0.01 s−1 to 0.0001 s−1. The flow stress and microstructure evolution were investigated and the constitutive model was established. The results indicated that the Mo2TiAlC2 strengthens the Mo-12Si-8.5B alloy mainly by particle strengthening and grain boundary strengthening at high temperatures. With the increase of Mo2TiAlC2 content, the peak stress of the alloys improved. As the temperature increases or the strain rate decreases, the peak stress of the alloys decreases significantly. The microstructure reveals that the deformation of the Mo-12Si-8.5B-Mo2TiAlC2 alloy at high temperatures is mainly provided by the deformation of the α-Mo phase and grain boundary sliding. As the temperature rises to 1300–1400°C, the intermetallic phase gradually participates in the deforming but contributes less to the total deformation. Dynamic recovery and recrystallization greatly reduce dislocations at high temperatures. The Mo2TiAlC2 particles can inhibit recrystallization grain growth. In addition, the flow stress values of the Mo-12Si-8.5B-2 wt.% Mo2TiAlC2 alloy calculated by the constitutive model are in good agreement with the experimental values. Hence, it is reasonable to believe that the constitutive model can effectively predict the rheological behavior of alloys at high temperatures. [ABSTRACT FROM AUTHOR]

This study addresses the poor robustness of the current beamforming algorithm for covariance matrix reconstruction and the high computational complexity in the covariance matrix reconstruction process. A robust beamforming algorithm based on the Complex Gauss–Legendre integral is proposed. The method firstly partitions the neighborhood of the interference signal and constructs the interference signal space using the complex Gauss-Legendre integral, then projects the received signal into the interference signal space to filter out the desired signal and complete the reconstruction of the interference noise covariance matrix, before finally correcting the steering vector mismatch using the improved optimal steering vector estimation method. The simulation results show that the method has good robustness and a low sidelobe in the presence of the steering vector mismatch and the presence of array perturbation. Compared with the previous works, the proposed CGL-ISV method provides a better beamforming performance. [ABSTRACT FROM AUTHOR]