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Floor water inrush has always been an important problem affecting coal mine safety. The water inrush from the deep coal seam floor is the final manifestation of the water inrush channel formed by the expansion and penetration of rock mass cracks under the combined action of a high ground temperature, high ground stress, high karst water pressure and strong mining disturbance. The fault is a structurally weak plane developed in the complete rock layer, which can be regarded as a permeable channel with good permeability. In order to explore the location of confined water from the fault to rock stratum caused by the tensile fracture of a fault during floor water inrush, floor water inrush is regarded as the result of the joint action of water pressure and mining stress. The COMSOL Multiphysics numerical simulation software was used to simulate the advancing process of the working face of the coal seam with a fault structure. Different fault dip models were established for comparative analysis. The objective weight CRITIC based on data volatility was used to analyze the water pressure and principal stress near the fault. The results show that the uplift strength of highly confined water increases with the increase in the fault dip angle, and the weight of water pressure near the fault has a certain relationship with the location of the water body entering the rock stratum from the fault. [ABSTRACT FROM AUTHOR]

Sports facilities have been acknowledged as one of the crucial environmental factors for children's physical education, physical fitness, and participation in physical activity. Finding a solution for the effective and objective evaluation of the condition of sports facilities in schools (SSFs) with the responding quantitative magnitude is an uncertain task. This paper describes the utilization of an unsupervised machine learning method to objectively evaluate the condition of sports facilities in primary school (PSSFC). The statistical data of 845 samples with nine PSSFC indicators (indoor and outdoor included) were collected from the Sixth National Sports Facility Census in mainland China (NSFC), an official nationwide quinquennial census. The Fuzzy C-means (FCM) algorithm was applied to cluster the samples in accordance with the similarity of PSSFC. The clustered data were visualized by using t-stochastic neighbor embedding (t-SNE). The statistics results showed that the application of t-SNE and FCM led to the acceptable performance of clustering SSFs data into three types with differences in PSSFC. The effects of school category, location factors, and the interaction on PSSFC were analyzed by two-way analysis of covariance, which indicated that regional PSSFC has geographical and typological characteristics: schools in the suburbs are superior to those in the inner city, schools with more grades of students are configured with better variety and larger size of sports facilities. In conclusion, we have developed a combinatorial machine learning clustering approach that is suitable for objective evaluation on PSSFC and indicates its characteristics. [ABSTRACT FROM AUTHOR]

The unfolded protein response (UPR) maintains cellular proteostasis during stress by activating sensors located to the endoplasmic reticulum (ER) membrane. A major sensor for this response, ATF6α, is activated by release from ER retention and trafficking to the Golgi, where it is cleaved to generate a bZIP transactivator to initiate a transcriptional response. The reduction of a disulfide in monomeric ATF6α is thought to be necessary for release from retention, trafficking, and proteolysis. Here we show that, following ER stress, ATF6α undergoes a redox switch to form a disulfide bonded dimer, which traffics to the Golgi for cleavage by the S1P protease. Additionally, we find that overexpression of ERp18 attenuates dimer formation thereby limiting Golgi trafficking. Our results provide mechanistic insight into activation of the ATF6α pathway, revealing an unexpected role for redox-dependent oligomerization prior to Golgi trafficking. [ABSTRACT FROM AUTHOR]

Due to the limitations of the urban environment, the data transferred between vehicles can only change direction at the intersections. Therefore, the routing decision at an intersection will largely affect the overall routing decision. In this article, we propose an Intersection-Based Routing with Fuzzy Multi-Factor Decision (IRFMF), which utilizes several factors to decide the next road segment. In the scheme, each intersection introduces three factors including the direction, the number of lanes, and the traffic. After the fuzzification and defuzzification of these factors, the candidate segment with the highest evaluation will be selected. The simulation shows a significant improvement of VANETs performance on packet delivery ratio and end-to-end delay. [ABSTRACT FROM AUTHOR]

Aims: The post-translational oxidation of methionine to methionine sulfoxide (MetSO) is a reversible process, enabling the repair of oxidative damage to proteins and the use of sulfoxidation as a regulatory switch. MetSO reductases catalyze the stereospecific reduction of MetSO. One of the mammalian MetSO reductases, MsrB3, has a signal sequence for entry into the endoplasmic reticulum (ER). In the ER, MsrB3 is expected to encounter a distinct redox environment compared with its paralogs in the cytosol, nucleus, and mitochondria. We sought to determine the location and arrangement of MsrB3 redox-active cysteines, which may couple MsrB3 activity to other redox events in the ER. Results: We determined the human MsrB3 structure by using X-ray crystallography. The structure revealed that a disulfide bond near the protein amino terminus is distant in space from the active site. Nevertheless, biochemical assays showed that these amino-terminal cysteines are oxidized by the MsrB3 active site after its reaction with MetSO. Innovation: This study reveals a mechanism to shuttle oxidizing equivalents from the primary MsrB3 active site toward the enzyme surface, where they would be available for further dithiol-disulfide exchange reactions. Conclusion: Conformational changes must occur during the MsrB3 catalytic cycle to transfer oxidizing equivalents from the active site to the amino-terminal redox-active disulfide. The accessibility of this exposed disulfide may help couple MsrB3 activity to other dithiol-disulfide redox events in the secretory pathway. [ABSTRACT FROM AUTHOR]

Vehicular ad hoc network (VANET) is a special form of mobile ad hoc network (MANET), which plays a key role in the intelligent transportation system (ITS). Though many outstanding geographic routing protocols are designed for VANETs, a majority of them use parameters that only affect routing performance. In this article, we propose an intersection routing based on fuzzy multi-factor decision (IRFMFD), which utilizes several features. The scheme is divided into two parts, namely vehicular decision management and intersection decision management. In the vehicular component, candidate vehicles between two static nodes (SNs) located at two intersections derive potential routing paths considering distance, neighbor quantity, and relative velocity. In the intersection component, the candidate SN was chosen from the current intersection's 2-hop neighbors which were connected with the current intersection by a route that was decided on in part one. To get the best scheme, we also introduced other factors to estimate the number of hops in each link and link lifetime. The simulation shows that the IRFMFD outperforms on delivery ratio and end-to-end delay compared with AODV (Ad hoc on-demand distance vector), GPSR (Greedy perimeter stateless routing) and GeOpps (Geographical opportunistic routing). [ABSTRACT FROM AUTHOR]

Purpose. To evaluate the relationships between objectively measured physical activity and physical fitness among preschool children. Methods. A total of 346 participants (201 boys and 145 girls) aged 3.5–5.5 years (M=4.5 yr, SD = 0.47) from Shanghai, China, completed physical fitness assessments, including triceps skinfold thickness (TSFT), grip strength, tennis throwing, sit and reach test, standing long jump, balance beam, 10mSRT, and 20mSRT. Physical activity was objectively measured by ActiGraphGT3X+ accelerometer. Multiple linear regression models were used to explore the cross-sectional associations between PA and physical fitness after adjusting for age, gender, BMI, and valid wearing time. Results. Positive associations were observed between stand long jump (p<.01), tennis throwing (p<.01), laps in 20mSRT (p<.01), and MVPA. However, TSFT (p<.05), time in 10mSRT (p<.01), and balance beam (p<.05) were negatively associated with MVPA. Furthermore, positive associations were found between stand long jump (p<.01), tennis throwing (p<.01), and MVPA only in boys. Negative associations were found between time on balance beam (p<.01) and MVPA only in girls. Conclusions. MVPA appears to be an effective and reliable predictor of preschoolers’ physical fitness. Boys’ body composition, muscular strength, explosive strength, agility, aerobic fitness, girls’ agility, aerobic fitness, and balance could improve as MVPA increases. [ABSTRACT FROM AUTHOR]

A new rare earth ternary iodate, Ce2I6O18, has been synthesized by a high temperature hydrothermal method with homemade alloy reactor equipment. It crystallizes in the monoclinic system space group P21 with a = 8.7252(2) Å, b = 7.0474(1) Å, c = 13.096(3) Å, β = 90.81(0)°, Z = 2, and V = 805.2(3) Å3. The material exhibits a three dimensional structure consisting of unlimited extending CeO9 polyhedrons and IO3 triangular pyramidal bilayers connected by I…O long bonds. The electronic band structure and optical properties of Ce2I6O18 were studied. It belongs to the type I phase-matchable class with an IR cutoff wavelength of 12.2 μm and second-harmonic generation (SHG) response of about 9 × KH2PO4 (KDP). [ABSTRACT FROM AUTHOR]

Mitochondrial 2-cys peroxiredoxin III (PrxIII) is a key player in antioxidant defence reducing locally-generated H2O2 to H2O. A Phe to Leu (F190L) mutation in the C-terminal α-helix of PrxIII, mimicking that found in some bacteria and parasites, increases its resistance to hyperoxidation but has no obvious influence on peroxidase activity. Here we report on the oxidized and reduced crystal structures of bovine PrxIII F190L at 2.4 Å and 2.2 Å, respectively. Both structures exist as two-ring catenanes with their dodecameric rings inclined at 55o to each other, similar to that previously reported for PrxIII C168S. The new higher-resolution structures reveal details of the complex network of H-bonds stabilising the inter-toroid contacts. In addition, Arg123, the key conserved residue, that normally interacts with the catalytic cys (Cp, cys 47) is found in a distinct conformation extending away from the Cp while the characteristic Arg-Glu-Arg network, underpinning the active-site geometry also displays a distinctive arrangement, not observed previously. This novel active-site organisation may provide new insights into the dynamics of the large-scale conformational changes occurring between oxidized and reduced states. [ABSTRACT FROM AUTHOR]

Presents information on a study which discussed the preparation of the selenomethionine derivative of tabtoxin resistance protein. Background on multiwavelength anomalous dispersion for phase evaluation in crystallography; Methodology; Results and discussion.

Tabtoxin-resistance protein (TTR), an acetyltransferase from Pseudornonas syringae pv. tabaci, was overexpressed in Eschericha coli M15 and the TTR fusion protein complexed with acetyl- coenzyme A (AcCoA) was purified and crystallized. Diffraction data were collected to 3.0 Å resolution in-house and the crystal was found to belong to space group P21, with unit-cell parameters a = 47.6, b = 66.6, c = 53.5 Å, β = 104.3°. Furthermore, a selenomethionine (SeMet) TTR fusion protein derivative was overexpressed in the same expression system and its complex with AcCoA was purified in a reductive environment. The SeMet TTR derivative crystallized in two forms: the first was identical to that observed thr native crystals and the second belonged to space group c2, with unit-cell parameters a = 101.7, b = 45.6, c = 84.2 Å, β = 105.8°. Data from the P21 crystal form were collected in-house to 2.3 Å resolution. Subsequently, three different wavelength data sets of the C2 crystal form to 1.55 Å resolution were collected at the Advanced Photon Source at Argonne National Laboratory. [ABSTRACT FROM AUTHOR]

Aqueous lithium ion batteries (ALIBs) attract wide attentions due to their high safety, low cost and environmental friendliness. The performance of anode material is the limiting step for the wide application of ALIBs. Here, a core-composite-shell structure of Cu x Ti 2 (PO 4) 3 @Cu/C is rationally designed, synthesized and investigated as a promising anode material for ALIBs. With high electronic and lithium ion conductivity in internal core and external shell simultaneously, the Cu x Ti 2 (PO 4) 3 @Cu/C anode material shows excellent electrochemical performance. It delivers a specific capacity 135 mA h·g−1 at 10 mA g−1 (the largest value reported), excellent rate behaviors of 95 mA h·g−1 at 2000 mA g−1, as well as long high rate cycling lifetimes (~80% after 900 cycles at 1000 mA g−1). This work not only provides a new anode material for ALIBs, but also proposes a new material structure design strategy and a facile synthesis method for the preparation of other alkali ions battery electrode materials. Image 1 • A Cu x Ti 2 (PO 4) 3 @Cu/C core-composite-shell structure is rationally designed. • Cu x Ti 2 (PO 4) 3 @Cu/C possesses good electronic and lithium ion transport ability. • Cu x Ti 2 (PO 4) 3 @Cu/C delivers the largest capacity of 135 mA h·g−1 ever repoeted. • The electrochemical reaction mechanism is studied by in-situ XRD. [ABSTRACT FROM AUTHOR]

A novel fluorescence chemosensor array composed of pyrenylboronic acid-based probes for multi- anion detection has been developed. The pyrenylboronic acid derivatives showed fluorescence quenching or enhancement due to photoinduced electron transfer originating from anion binding. The recognition ability was assessed by fluorescence titrations and electrospray ionization mass spectrometry. Because the array is constructed with cross-reactive probes, the combination of differential binding affinities for anions (i.e., fluoride, acetate, oxalate, malonate, citrate, dihydrogen phosphate, and pyrophosphate) and pattern recognitions, such as linear discriminant analysis, offered a successful simultaneous anion detection with a classification rate of 100%. Furthermore, the chemosensor array allowed for quantitative prediction of oxalate, malonate, and citrate in mixtures using a support vector machine. Importantly, the array system employs low-cost and commercially available reagents as probes. Thus, this study could lead to the development of user-friendly and high-throughput methods to detect a variety of analytes in complicated systems., (Copyright © 2020 Cao, Cao, Kubota, Sasaki, Asano, Lyu, Zhang, Zhou, Zhao, Xu, Wu, Minami and Liu.)

Folding of proteins entering the mammalian secretory pathway requires the insertion of the correct disulfides. Disulfide formation involves both an oxidative pathway for their insertion and a reductive pathway to remove incorrectly formed disulfides. Reduction of these disulfides is crucial for correct folding and degradation of misfolded proteins. Previously, we showed that the reductive pathway is driven by NADPH generated in the cytosol. Here, by reconstituting the pathway using purified proteins and ER microsomal membranes, we demonstrate that the thioredoxin reductase system provides the minimal cytosolic components required for reducing proteins within the ER lumen. In particular, saturation of the pathway and its protease sensitivity demonstrates the requirement for a membrane protein to shuttle electrons from the cytosol to the ER. These results provide compelling evidence for the crucial role of the cytosol in regulating ER redox homeostasis, ensuring correct protein folding and facilitating the degradation of misfolded ER proteins., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2020. Published by The Company of Biologists Ltd.)

The oxidation of methionine residues in proteins occurs during oxidative stress and can lead to an alteration in protein function. The enzyme methionine sulfoxide reductase (Msr) reverses this modification. Here, we characterise the mammalian enzyme Msr B3. There are two splice variants of this enzyme that differ only in their N-terminal signal sequence, which directs the protein to either the endoplasmic reticulum (ER) or mitochondria. We demonstrate here that the enzyme can complement a bacterial strain, which is dependent on methionine sulfoxide reduction for growth, that the purified recombinant protein is enzymatically active showing stereospecificity towards R -methionine sulfoxide, and identify the active site and two resolving cysteine residues. The enzyme is efficiently recycled by thioredoxin only in the presence of both resolving cysteine residues. These results show that for this isoform of Msrs, the reduction cycle most likely proceeds through a three-step process. This involves an initial sulfenylation of the active site thiol followed by the formation of an intrachain disulfide with a resolving thiol group and completed by the reduction of this disulfide by a thioredoxin-like protein to regenerate the active site thiol. Interestingly, the enzyme can also act as an oxidase catalysing the stereospecific formation of R -methionine sulfoxide. This result has important implications for the role of this enzyme in the reversible modification of ER and mitochondrial proteins., (© 2018 The Author(s).)

Peroxiredoxins (Prxs) are a large and conserved family of peroxidases that are considered to be the primary cellular guardians against oxidative stress in all living organisms. Prxs share a thioredoxin fold and contain a highly-reactive peroxidatic cysteine in a specialised active-site environment that is able to reduce their peroxide substrates. The minimal functional unit for Prxs are either monomers or dimers, but many dimers assemble into decameric rings. Ring structures can further form a variety of high molecular weight complexes. Many eukaryotic Prxs contain a conserved GGLG and C-terminal YF motif that confer sensitivity to elevated levels of peroxide, leading to hyperoxidation and inactivation. Inactive forms of Prxs can be re-reduced by the enzyme sulfiredoxin, in an ATP-dependent reaction. Cycles of hyperoxidation and reactivation are considered to play an integral role in a variety of H 2 O 2 -mediated cell signalling pathways in both stress and non-stress conditions. Prxs are also considered to exhibit chaperone-like properties when cells are under oxidative or thermal stress. The roles of various types of covalent modifications, e.g. acetylation and phosphorylation are also discussed. The ability of Prxs to assemble into ordered arrays such as nanotubes is currently being exploited in nanotechnology.

The membrane topology of vitamin K epoxide reductase (VKOR) is controversial with data supporting both a three transmembrane and a four transmembrane model. The positioning of the transmembrane domains and the loops between these domains is critical if we are to understand the mechanism of vitamin K oxidation and its recycling by members of the thioredoxin family of proteins and the mechanism of action of warfarin, an inhibitor of VKOR. Here we show that both mammalian VKOR isoforms adopt the same topology, with the large loop between transmembrane one and two facing the lumen of the endoplasmic reticulum (ER). We used a redox sensitive green fluorescent protein (GFP) fused to the N- or C-terminus to show that these regions face the cytosol, and introduction of glycosylation sites along with mixed disulfide formation with thioredoxin-like transmembrane protein (TMX) to demonstrate ER localization of the major loop. The topology is identical with the bacterial homologue from Synechococcussp., for which the structure and mechanism of recycling has been characterized. Our results provide a resolution to the membrane topology controversy and support previous results suggesting a role for members of the ER protein disulfide isomerase (PDI) family in recycling VKOR., (© 2016 Authors; published by Portland Press Limited.)

Hydrogen peroxide (H2O2) can act as a signalling molecule affecting the cell cycle as well as contributing towards the oxidative stress response. The primary target of this molecule is oxidation-sensitive cysteine residues in proteins such as protein tyrosine phosphatases. The cell has robust mechanisms to remove H2O2 that need to be regulated for H2O2 to react with and modify protein thiols. In particular, the family of peroxiredoxins are capable of the rapid removal of even trace amounts of this molecule. It has been suggested that the inactivation of peroxiredoxins by hyperoxidation may allow H2O2 levels to increase in cells and thereby modify critical thiol groups in proteins. We have been studying how the H2O2 produced during disulfide formation in the ER (endoplasmic reticulum) is metabolized and have shown that ER-resident peroxiredoxin IV not only can remove H2O2, but also contributes to de novo disulfide formation. In the present article, we review recent data on the structure and function of this enzyme as well as its sensitivity to hyperoxidation.

A new potential infrared (IR) nonlinear optical (NLO) material Bi(2)(IO(4))(IO(3))(3) was synthesized by hydrothermal method. Bi(2)(IO(4))(IO(3))(3) crystallizes in the chiral orthorhombic space group P2(1)2(1)2(1) (No. 19) with a = 5.6831(11) Å, b = 12.394(3) Å, and c = 16.849(3) Å. It exhibits a three-dimensional framework through a combination of the IO(3), IO(4), BiO(8), and BiO(9) polyhedra and is the first noncentrosymmetric (NCS) structure containing [IO4](3-) anion. Bi(2)(IO(4))(IO(3))(3) has an IR cutoff wavelength of 12.3 μm and belongs to the type 1 phase-matchable class with a moderately large SHG response of 5 × KDP, which is in good agreement with the theoretical calculations., (© 2011 American Chemical Society)

Mitochondria are the major intracellular sites of oxygen consumption producing reactive oxygen species (ROS) as toxic by-products of oxidative phosphorylation, primarily via electron leakage from the respiratory chain. The resultant types of chemical damage to lipids, DNA and proteins are described as well as the broader implications for the involvement of ROS in disease onset and progression. The relative contributions of mitochondrial, enzyme-linked, antioxidant defence systems to tissue protection are also reviewed as is the emerging importance of the peroxiredoxin family in general to H2O2-mediated signalling The constituent enzymes of the mitochondrial PrxIII pathway are discussed in detail including the roles of PrxIII and PrxV in their capacities as typical 2-cys and atypical 2-cys thioredoxin-dependent hydroperoxide reductases, respectively. The structures and catalytic mechanisms of PrxIII and V are examined and some key properties of the reconstituted mitochondrial PrxIII pathway are highlighted with specific reference to the susceptibility of peroxiredoxins to inactivation at elevated H2O2 levels and their potential for participation in H2O2-mediated signalling responses. It is concluded that mitochondrial Prxs form a vital link in an integrated cellular antioxidant defence network that minimises ROS-mediated damage and ensures that cells mount appropriate responses to increased levels of oxidative stress via the upregulation of key cell signalling pathways.