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A four‐step metal‐free procedure is described for the transformation of 4‐hydroxy‐2‐methylcyclopent‐2‐enone derivatives into highly functionalized E‐alkylidenecyclobutanes featuring oxygenated tetrasubstituted centers. The key intermediate is a (cyclobutenyl)propane‐1,3‐diol diester, easily accessed via a tandem photochemical reaction, which undergoes an original Brønsted acid‐catalyzed allylic substitution reaction with alcohols to give the title products with ester‐protected primary alcohol side chains. [ABSTRACT FROM AUTHOR]

ABSTRACT Increasing evidence supports the idea that bone morphogenetic proteins (BMPs) regulate cartilage maintenance in the adult skeleton. The aim of this study is to obtain insight into the regulation of BMP activities in the adult skeletal system. We analyzed expression of Noggin and Gremlin1, BMP antagonists that are known to regulate embryonic skeletal development, in the adult skeletal system by Noggin-LacZ and Gremlin1-LacZ knockin reporter mouse lines. Both reporters are expressed in the adult skeleton in a largely overlapping manner with some distinct patterns. Both are detected in the articular cartilage, pubic symphysis, facet joint in the vertebrae, and intervertebral disk, suggesting that they regulate BMP activities in these tissues. In a surgically induced knee osteoarthritis model in mice, expression of Noggin mRNA was lost from the articular cartilage, which correlated with loss of BMP2/4 and pSMAD1/5/8, an indicator of active BMP signaling. Both reporters are also expressed in the sterna and rib cartilage, suggesting an extensive role of BMP antagonism in adult cartilage tissue. Moreover, Noggin-LacZ was detected in sutures in the skull and broadly in the nasal cartilage, while Gremlin1-LacZ exhibits a weaker and more restricted expression domain in the nasal cartilage. These results suggest broad regulation of BMP activities by Noggin and Gremlin1 in cartilage tissues in the adult skeleton, and that BMP signaling and its antagonism by NOGGIN play a role in osteoarthritis development. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1671-1682, 2017. [ABSTRACT FROM AUTHOR]

Math anxiety is a widespread problem for children and adolescents worldwide. However, the psychological trait of math anxiety is poorly understood. The present study aimed to examine the psychological construct of math anxiety among social‐emotional attitudes. A total of 28,726 students, including 17,378 fourth graders and 11,348 eighth graders, were selected from the Qingdao Basic Education Quality Assessment database using multi‐stage cluster random sampling. There were 10 questionnaires assessing social‐emotional attitudes in the database. Pearson's correlation analyses were performed to examine the intercorrelations between social‐emotional attitudes and mathematical performance. Exploratory factor analysis (EFA) was conducted to examine the psychological structure of these 10 social‐emotional attitudes. After controlling for other social‐emotional attitudes, math anxiety had a weak but significant correlation to mathematical performance in most subtests across grades. Among three‐factor, four‐factor, and five‐factor EFA models, math anxiety was an independent factor that was separate from other social‐emotional attitudes across six parallel subtests in grades four and eight. Math anxiety is a stable and independent psychological construct that is separate from other social‐emotional attitudes. It suggests that math anxiety should be considered as a distinct anxiety disorder specific to mathematical learning in subsequent versions of the Diagnostic and Statistical Manual of Mental Disorders. [ABSTRACT FROM AUTHOR]

Background Maternal vitamin D status has been reported to be associated with childhood allergic diseases. However, this association remains to be fully elucidated. Methods A systematic review and meta-analysis was conducted using prospective cohort studies that examined the association between maternal vitamin D status and childhood allergic diseases including wheeze, eczema and asthma. We searched electronic databases of PubMed, EMBASE, the Cochrane library, the Wanfang (Chinese) database, the VIP (Chinese) database, and Chinese National Knowledge Infrastructure (CNKI) up to August 2014. Odds ratios and 95% confidence intervals (CIs) from individual studies were synthesized using a fixed effects model. Results Four studies on the association between maternal vitamin D status and childhood asthma (3666 mother-child pairs), four studies on the association between maternal vitamin D status and childhood wheeze (2225 mother-child pairs) and three papers on the association between maternal vitamin D status and childhood eczema (2172 mother-child pairs) met our inclusion criteria. Maternal vitamin D status during pregnancy was associated with childhood eczema (pooled OR=0.904, 95% CI=0.831-0.983). However, the meta-analysis showed no statistical association between maternal vitamin D status and childhood asthma (pooled OR=0.981, 95% CI=0.944-1.019) or childhood wheeze (pooled OR=0.995, 95% CI=0.982-1.009). Conclusions Our meta-analysis found that lower maternal vitamin D during pregnancy was associated with an increased risk of childhood eczema but was not associated with childhood asthma or wheeze. The role of maternal vitamin D as an important protective factor for the development of childhood eczema remains to be elucidated. [ABSTRACT FROM AUTHOR]

The article discusses a research concerning the key technology of micro area visualization applied in oil and gas exploration and development. It highlights the importance of micro area visualization technology for engineers in solving reservoir problems as well as cites some of the technical problems in micro area visualization technology. Key technologies addressed include high precision digital image matching technology and frozen core grinding slice oil-water rock technology.

With the increasing distribution network accidents caused by typhoon disasters, risk management in typhoon scenarios is necessary. A risk management framework for power distribution networks (PDNs) undergoing a typhoon disaster is proposed. First, a risk prediction model of the PDN under typhoon conditions based on the Batts model is developed to predict the loss of load risk (LLR) index and economic loss risk (ELR) index of the PDN before the typhoon lands. Then, a vulnerability index of overhead lines, considering the failure frequency of specific overhead lines and their load importance, is introduced for use in a weak link identification model to identify weak links in the PDN. Finally, a two‐time‐step risk relief model based on typhoon forecast information and the identified weak links is developed to allocate PDN relief materials to reduce the LLR and ELR during a typhoon disaster. An IEEE RBTS BUS6 system is employed as a test system to verify the risk management strategy. The vulnerability index proposed by the strategy considers both the importance of load and line failure. The risk management strategy adopts a two‐time‐step model, which reduces the impact of meteorological forecast errors and enables more efficient use of materials. The results show that the proposed framework can take more effective use of relief materials to reduce the loss of PDNs compared with the traditional strategy. [ABSTRACT FROM AUTHOR]

Layered nickel silicate nanoflowers (NSFs) with a hierarchical nanostructure have been successfully fabricated by a template-free solvothermal method. The as-prepared nanoflowers were composed of many interconnected edge-curving lamellae with a thickness of about 15 nm and had a high specific surface area (279 m2 g−1) and large pore volume (0.67 cm3 g−1). The highly dispersed small silver nanoparticles (AgNPs) were immobilized on the surface of NSFs through the in situ reduction of Ag+ by Sn2+. The AgNP/NSF nanocomposites showed a high performance in the catalytic reduction of 4-nitrophenol. In particular, there was no visible decrease in the catalytic activity of the reused catalysts even after being recycled four times. The as-prepared AgNP/NSF nanocomposites might be an excellent catalyst owing to their availability, formability, chemical and thermal stability, and high specific surface area. [ABSTRACT FROM AUTHOR]

Whether SOX2 and ACTL6A/TP63 interact with the Hippo‐YAP1 pathway in esophageal squamous cell carcinoma (ESCC) remains unclear. Here, we reveal that SOX2, ACTL6A, and TP63 are co‐amplified and upregulated in ESCC samples. Multiple SOX2 binding peaks in the locus of WWC1, a Hippo‐YAP1 regulator, and an inverse correlation between the expression of SOX2 and WWC1 are identified, suggesting direct repression of WWC1 by SOX2. Expression scores of SOX2 are higher in tumors than normal tissues and positively correlated with nuclear YAP1 staining in primary ESCC. Moreover, SOX2 gain‐of‐function significantly promotes nuclear YAP1 expression in ESCC cells while silencing of SOX2 expression inhibits YAP1 activation. SOX2 overexpression leads to a significant enhancement of cell migration and invasion as well as chemoresistance to cisplatin, whereas knockdown of SOX2 or ectopic expression of WWC1 suppresses the SOX2‐induced migration ability and invasive potential. Disruption of this SOX2‐WWC1‐YAP1 axis could be a therapeutic strategy for SOX2‐dependent tumors. [ABSTRACT FROM AUTHOR]

Highly dispersible Mo0.42C0.58 nanoparticles in nitrogen‐doped carbon is achieved via pyrolyzing one‐dimensional NH4Ni2Mo2O8(OH)H2O@polypyrrole nanocomposites. The formation of the Mo0.42C0.58 is realized via the reaction between the NH4Ni2Mo2O8(OH)H2O nanorod as core and the carbonized polypyrrole at a high temperature. The Mo0.42C0.58@N‐doped carbon presents satisfied catalytic activity towards oxygen reduction reaction with the half‐wave potential of 0.828 V vs. RHE (reversible hydrogen electrode), comparable to that of the commercial Pt/C catalyst. Furthermore, the sample illustrates superior stability and methanol tolerance to Pt/C. The excellent catalytic activity of the Mo0.42C0.58@N‐doped carbon can be attributed to the existence of Mo0.42C0.58 nanoparticles, the N doping in carbonized polypyrrole, and the well‐maintained one‐dimensional nanostructure. [ABSTRACT FROM AUTHOR]

Improving the computational efficiency of reliability assessment is a long‐term goal for researchers. Regarding this issue, an impact‐increment‐based decoupled reliability assessment approach (IID) is proposed in this study. First, a new formulation of reliability indices is derived by decoupling the reliability index of composite systems into two parts: generation adequacy and transmission reliability. Then, an impact‐increment‐based state enumeration reliability assessment method is implemented to both the parts, which are more efficient than tradition methods. Thereafter, a reduction technique for the higher‐order contingency states is developed for the transmission reliability evaluation. With this technique, the number of analysed contingencies can be significantly reduced, which improves the computational speed significantly. Finally, the overall framework of the proposed IID approach is demonstrated. Case studies are performed on the RTS‐79, RTS‐96 and a provincial system of China. Results indicate that the proposed method has superior performance to the traditional reliability assessment methods in terms of accuracy and computational speed, particularly on large‐scale composite systems. [ABSTRACT FROM AUTHOR]

Abstract: In this work, TiO2 nanosponge, replication of a bio‐template by a sol–gel method was achieved with filter paper. High‐dispersed Au and Pt nanoparticles (NPs) with controllable size were immobilized on the surface of TiO2 nanosponge, respectively. The obtained noble metal NPs/TiO2 nanosponge composites were characterized by various techniques. Catalytic activity of the synthesized Au/TiO2 nanocomposites was assessed by the reduction of 4‐nitrophenol (4‐NP), while the catalytic performance of the as‐synthesized Pt/TiO2 nanosponge composites was evaluated by the CO oxidation reaction. Notably, the Au/TiO2 and Pt/TiO2 nanocomposites demonstrated a good catalytic activity and stability for the catalytic reduction of 4‐NP and the catalytic oxidation of CO, respectively. [ABSTRACT FROM AUTHOR]

Magnesium silicate double-walled hollow nanofibers (MSHNFs) with a hierarchical nanostructure have been successfully fabricated by combining the electrospinning technique with a hydrothermal method. The as-prepared MSHNFs are composed of numerous ultrathin nanosheets with a thickness of approximately 10 nm and have a high specific surface area (632.2 m2 g−1) and large pore volume (0.92 cm3 g−1). The MSHNFs exhibit high adsorption capacity and excellent stability in a purification test with organic molecules and a solution of heavy-metal ions. Moreover, the MSHNFs can be easily separated from solution by gravitational sedimentation owing to their unique structure. [ABSTRACT FROM AUTHOR]