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In China, there exists many factors such as girls' socialized gender norms and the values and pedagogy incorporated in the science curriculum that may discourage female students from choosing science courses. In order to ensure that female students have the same opportunities to reach their potential in STEM areas, it is important to understand these factors that influence their choices. This study investigates the potential reasons why female high school students in China are less likely to choose STEM subjects. By conducting qualitative interviews with six female students, from two Chinese high schools, the study discovers several factors behind their decision-making in course selection, including the influence of current science curriculum, teachers, labor market, parents, and peers. The findings of this study enrich existing research on gender equity in Chinese high school education and provide insights about relevant policies to address gender disparities in science programs.

Contamination of heavy metal(loid) in soils is a global problem. Various remediation technologies have thus been applied to mitigate the ecological and health risk of heavy metal(loid)s in contaminated soils. Majority of review studies mainly focus on the mobility or accumulation of heavy metal(loid)s, but little attention has been paid to the alteration of soil fertility (e.g. soil nutrient, structure and enzyme activities) which are most closely related to plant growth during the remediation process. Here, we summarized influence of physical, chemical and biological remediation technologies of contaminated soils on soil fertility, and they indicated that: (1) thermal treatment and soil washing usually decreased soil nutrients and enzyme activities, as well as deteriorated soil structure; (2) biological technologies usually improved soil structure or microorganism activities, but the decrease of soil fertility through nutrient uptake by plants cannot be ignored; (3) the soil amendments displayed various influence on soil fertility, which depended on their properties; (4) combination of multiple technologies could neutralize the negative influence of single technology on soil fertility. In the future, technologies which could both decrease heavy metal(loid) toxicity and improve soil fertility are more recommended. [ABSTRACT FROM AUTHOR]

Owing to the fact that chemical activity of numerous VOCs (volatile organic compounds) differs greatly, the contributions of the more active species VOCs could be weakened in case the source apportionment of VOCs is carried out merely using the observed data of VOCs concentration, which is detrimental to the VOCs emission reduction and ozone pollution alleviation. To effectively reduce the influence of photochemical loss on VOCs source apportionment, in this study the initial concentrations of VOCs were estimated by photochemical aging method to correct the photochemical loss of ambient VOCs species, and then the positive matrix factorization (PMF) was used to conduct source apportionment of ambient VOCs. The findings of the study suggested that the average observed concentration of ambient VOCs during the observation period was (23.90±5.79)X10-9, and the initial concentration was (31.28±15.17)x10-9; and among others, variation of olefins was most drastic, being 4.33 times greater than the observed concentration, which was followed by aromatic hydrocarbons (1.87 times). The total average photochemical consumption of VOCs in daytime was 14.66X10-9, the photochemical consumption of olefin was the greatest, accounting for 70.7% of the total consumption. The daily variation trend of the initial concentration of ambient VOCs, O3 and temperature were basically consistent, reaching the maximum value of the initial concentration at 15: 00 with the biggst hourly maximum photochemical loss value (22.69X10-9). The photochemical loss of olefins and aromatics during O3 pollution days was greater than that during non-pollution days, and which became an important source of ozone generation. According to the results of the VOCs source apportionment of initial concentrations by use of PMF, the industrial pollution source in Xiangtan's urban area was the most remarkable contribution source during summer, while the secondary transformation was the biggst contributor source in accordance with the observed concentrations. [ABSTRACT FROM AUTHOR]

Pyrolusite modified carbon was prepared from walnut shell for enhancing removal of Cu(II) from aqueous solution. 1% pyrolusite addition was proved to be efficient and economic on adsorption capacity improvement of the produced carbon. Cu(II) removal rate on the modified walnut shell-based carbon was ca. 20% higher than the unmodified one, while the adsorption capacity for the modified carbon was high up to 34.4 mg/g. Within weakly acidic pH range (pH = 5 ~ 6), it was suitable for Cu(II) adsorption with larger than 97% removal rate on the produced carbon. SEM and BET analysis showed that pyrolusite played an important role on pore formation of the produced carbon. The specific surface area, mesopore and micropore volume of the modified carbon were 27.2%, 39.5%, 17.5%, respectively, higher than those of the unmodified one. After modification, oxygen-containing functional groups, especially phenol and carbonyl groups, were remarkably increased on the produced carbon, which were helpful for Cu(II)'s adsorption. FTIR showed that a large amount of organic carbon was decomposed into inorganic carbon skeleton during the carbonisation process, thus forming a large number of pores, and was conducive to adsorbing copper ions. This work is expected to be helpful for an effective agricultural residue management and innovative modification of walnut shell-based adsorbent as low-cost precursors for heavy metal treatment. [ABSTRACT FROM AUTHOR]

The dielectric behavior of insulations is a key factor affecting the development of anti-corona materials for generators. Epoxy resin (EP), as the matrix, is blended with inorganic fillers of micron SiC and nano SiO2 to investigate the effect of micro and nano doping on the conductivity and breakdown mechanism of the composites. Using experimental and simulation analysis, it is found that the effect of nano-SiO2 doping concentration on the conductivity is related to the dispersion of SiC particles. The lower concentration of SiO2 could decrease the conductivity of the composites. The conductivity increases with raising the nano-SiO2 doping concentration to a critical value. Meanwhile, the breakdown field strength of the composites decreases with the rising content of SiC in constant SiO2 and increases with more SiO2 when mixed with invariable SiC. When an equivalent electric field is applied to the samples, the electric field at the interface of micron particles is much stronger than the average field of the dielectric, close to the critical electric field of the tunneling effect. The density of the homopolar space charge bound to the surface of the stator bar elevates as the concentration of filled nanoparticles increases, by which a more effective Coulomb potential shield can be built to inhibit the further injection of carriers from the electrode to the interior of the anti-corona layer, thus reducing the space charge accumulation in the anti-corona layer as well as increasing the breakdown field strength of the dielectric. [ABSTRACT FROM AUTHOR]

Cytochrome b5 domain containing 2 (CYB5D2) (neuferricin) belongs to the family of membrane-associated progesterone receptors (MAPRs). MAPRs affect multiple cellular processes, including proliferation, differentiation, and survival. Consistent with these observations, we report here that CYB5D2 enhances HeLa cells survival of etoposide (ETOP)-mediated cytotoxicity. Overexpression of CYB5D2 enhanced the survival of HeLa cells compared with HeLa cells transfected with empty vector (EV) upon ETOP treatment. As ETOP initiates ATM-dependent DNA damage response (DDR), we were able to show that CYB5D2 did not affect ETOP-induced DDR. In line with these observations, CYB5D2 did not protect HeLa cells from UV-induced cytotoxicity. Additionally, CYB5D2 had no effects on TNFα-induced apoptosis. Collectively, CYB5D2 enhances HeLa cell survival of ETOP-induced cytotoxicity with some specificity. CYB5D2 contains a cytochrome b5 (cyt-b5) domain and a transmembrane (TM) motif. Both domains are required for CYB5D2-mediated protection of HeLa cells from ETOP-induced cytotoxicity. In an effort to search for the underlying mechanisms, we have profiled gene expression between HeLa-CYB5D2 and HeLa-EV cells. Although ectopic CYB5D2 does not massively alter gene expression, the expression of several transcripts was affected more than 2-fold, suggesting that they may contribute to CYB5D2-mediated HeLa cell survival of ETOP treatment. Key words: CYB5D2/neuferricin, cytotoxicity, apoptosis, cell cycle and DNA damage response. Resume : La neuferricine (CYB5D2, acronyme de Cytochrome b5 domain containing 2) appartient a la famille des recepteurs de la progesterone associes a la membrane (MAPR). Les MAPR affectent plusieurs processus cellulaires, notamment la proliferation, la differenciation et la survie. De maniere coherente avec ces observations, nous rapportons ici que CYB5D2 augmente la survie des cellules HeLa soumises aux effets cytotoxiques de l'etoposide (ETOP). La surexpression de CYB5D2 augmentait la survie des cellules HeLa comparativement aux cellules HeLa transfectees avec un vecteur vide (VV) a la suite du traitement a l'ETOP. Puisque le l'ETOP initie une reponse aux dommages a l'ADN dependante de l'ATM, nous avons pu demontrer que CYB5D2 n'affectait pas cette reponse induite par l'ETOP. Dans la foulee de ces observations, CYB5D2 ne protegeait pas les cellules HeLa de la cytotoxicite induite par les UV. De plus, CYB5D2 n'avait pas d'effet sur l'apoptose induite par le TNF-α. En somme, CYB5D2 augmente la survie des cellules HeLa traitees a l'ETOP avec une certaine specificite. CYB5D2 contient un domaine cytochrome b5 (cyt-b5) et un motif transmembranaire. Les deux domaines sont requis a la protection conferee par CYB5D2 vis-a-vis la cytotoxicite induite par l'ETOP chez les cellules HeLa. Afin de decouvrir les mecanismes sous-jacents, nous avons dresse un profil de l'expression genique chez les cellules HeLa-CYB5D2 et HeLa-VV. Meme si CYB5D2 ne modifie pas massivement l'expression genique, les niveaux d' expression de plusieurs transcrits etaient affectes de plus de deux fois, ce qui suggere que ces derniers peuvent contribuer a la survie des cellules HeLa conferee par CYB5D2 a la suite d'un traitement a l'ETOP. Mots-cles : CYB5D2/neuferricine, cytotoxicite, apoptose, cycle cellulaire, reponse aux dommages a l'ADN. [Traduit par la Redaction], Introduction Nongenomic actions of progesterone are mediated by the membrane progesterone receptors (mPRs), which include the 7 transmembrane PRs and the single transmembrane PRs (Bramley 2003; Brinton et al. 2008; [...]

Inactivation of phosphatase and tensin homolog (PTEN) is a critical step during tumorigenesis, and PTEN inactivation by genetic and epigenetic means has been well studied. There is also evidence suggesting that PTEN negative regulators (PTEN-NRs) have a role in PTEN inactivation during tumorigenesis, but their identity has remained elusive. Here we have identified shank-interacting protein-like 1 (SIPL1) as a PTEN-NR in human tumor cell lines and human primary cervical cancer cells. Ectopic SIPL1 expression protected human U87 glioma cells from PTEN-mediated growth inhibition and promoted the formation of HeLa cell-derived xenograft tumors in immunocompromised mice. Conversely, siRNA-mediated knockdown of SIPL1 expression inhibited the growth of both HeLa cells and DU145 human prostate carcinoma cells in vitro and in vivo in a xenograft tumor model. These inhibitions were reversed by concomitant knockdown of PTEN, demonstrating that SIPL1 affects tumorigenesis via inhibition of PTEN function. Mechanistically, SIPL1 was found to interact with PTEN through its ubiquitin-like domain (UBL), inhibiting the phosphatidylinositol 3,4,5-trisphosphate (PIP3) phosphatase activity of PTEN. Furthermore, SIPL1 expression correlated with loss of PTEN function in PTEN-positive human primary cervical cancer tissue. Taken together, these observations indicate that SIPL1 is a PTEN-NR and that it facilitates tumorigenesis, at least in part, through its PTEN inhibitory function., Introduction While PTEN displays phosphatase activity for both protein and lipid substrates (1), accumulating evidence reveals that its lipid phosphatase activity, which dephosphorylates the 3'-position phosphate from the inositol ring [...]