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Modulating the electronic configuration by coupling multi-scale active sites for electrocatalytic conversion of CO 2 to CO is extremely challenging in terms of structural analysis and mechanism elucidation. Herein, a catalyst NiAD/AgNPs@CN with both atomic-level dispersed Ni and Ag nanoparticles on N-doped carbon substrate has been designed to reveal the true active sites and catalytic mechanism in complex materials. NiAD/AgNPs@CN exhibits CO Faraday efficiency (FE CO) of 99.97% at −0.88 V (vs. RHE) in H-type cell and 91.77% FE CO with a high current density of 79.70 mA/cm2 in flow cell. DFT calculations show that the tiny change in the energy level of spin electrons at atomic sites has a significant impact on the CO 2 activation. The regulation of atomic Ni on Ag sites is the main reason for improving CO 2 RR performance. This work gives a new understanding on the catalytic mechanism of composite materials structured by atomic-level dispersed metal and nanoparticles. [Display omitted] • Atomic dispersed Ni surrounding with Ag nanoparticles was designed for CO 2 RR. • The synergistic effect between Atomic Ni sites and Ag nanoparticles was deeply explored. • Experiments combined with DFT study revealed the CO 2 RR mechanism. • The tiny change of spin electrons state has a significant impact on the activation of CO 2. [ABSTRACT FROM AUTHOR]

The type III secretion system encoded in the Salmonella pathogenicity island-2 (SPI-2) gene cluster facilitates intracellular growth of nontyphoidal Salmonella by interfering with the maturation of Salmonella-containing vacuoles along the degradative pathway. SPI-2 gene products also protect Salmonella against the antimicrobial activity of reactive oxygen species (ROS) synthesized by the phagocyte NADPH oxidase 2 (NOX2). However, a potential relationship between inflammatory ROS and the activation of transcription of SPI-2 genes by intracellular Salmonella is unclear. Here, we show that ROS engendered in the innate host response stimulate SPI-2 gene transcription. We found that the expression of SPI-2 genes in Salmonella-sustaining oxidative stress conditions involves DksA, a protein otherwise known to regulate the stringent response of bacteria to nutritional stress. We also demonstrate that the J and zinc-2-oxidoreductase domains of DnaJ as well as the ATPase activity of the DnaK chaperone facilitate loading of DksA onto RNA polymerase complexed with SPI-2 promoters. Furthermore, the DksA-driven transcription of SPI-2 genes in Salmonella experiencing oxidative stress is contingent on upstream OmpR, PhoP, and SsrB signaling events that participate in the removal of nucleoid proteins while simultaneously recruiting RNA polymerase to SPI-2 promoter regions. Taken together, our results suggest the activation of SPI-2 gene transcription in Salmonella subjected to ROS produced by the respiratory burst of macrophages protects this intracellular pathogen against NOX2-mediated killing. We propose that Salmonella have co-opted inflammatory ROS to induce SPI-2-mediated protective responses against NOX2 host defenses. [ABSTRACT FROM AUTHOR]

Insect chitin deacetylases (CDAs) catalyze the removal of acetyl groups from chitin and modify this polymer during its synthesis and reorganization. CDAs are essential for insect survival and therefore represent promising targets for insecticide development. However, the structural and biochemical characteristics of insect CDAs have remained elusive. Here, we report the crystal structures of two insect CDAs from the silk moth Bombyx mori: BmCDA1, which may function in cuticle modification, and BmCDA8, which may act in modifying peritrophic membranes in the midgut. Both enzymes belong to the carbohydrate esterase 4 (CE4) family. Comparing their overall structures at 1.98-2.4 Å resolution with those from well-studied microbial CDAs, we found that two unique loop regions in BmCDA1 and BmCDA8 contribute to the distinct architecture of their substrate-binding clefts. These comparisons revealed that both BmCDA1 and BmCDA8 possess a much longer and wider substrate-binding cleft with a very open active site in the center than the microbial CDAs, including VcCDA from Vibrio cholerae and ArCE4A from Arthrobacter species AW19M34-1. Biochemical analyses indicated that BmCDA8 is an active enzyme that requires its substrates to occupy subsites 0,+1, and +2 for catalysis. In contrast, BmCDA1 also required accessory proteins for catalysis. To the best of our knowledge, our work is the first to unveil the structural and biochemical features of insect proteins belonging to the CE4 family. [ABSTRACT FROM AUTHOR]

Due to the specific dynamics, the probes located at the halo orbits or Lissajous orbits around the Earth-Moon collinear libration point L 1 or L 2 are always studied in the synodic system to understand their trajectories. In fact, they are also orbiting the Earth in a distant Keplerian ellipse. Because of their intrinsic orbital instability, in the orbit prediction the initial errors propagate more prominently than those of the normal orbiting satellites, this requires special attention in the orbit design, maneuver, and control. Despite of all this, they are similar to the normal orbiting satellites in orbit determination and hardly require other special attentions. In this paper, the quantitative results of error propagation under the unstable dynamics, together with the theoretical analysis are presented. The results of precise orbit determination and short-arc orbit predictions are also shown, and compared with the results from the Beijing Aerospace Control Center. [ABSTRACT FROM AUTHOR]

Metal-oxygen batteries, especially Li-oxygen batteries (LOBs), have attracted tremendous research attentions in the past decades. It is necessary to design novel cost-effective catalysts in the development of high performance rechargeable LOBs. Herein, we prepare the atom-layered two-dimensional (2D) β -Co(OH) 2 nanosheets (AL- β -Co(OH) 2 ) via phase transition of layered α- Co(OH) 2 nanosheets ( α- Co(OH) 2 ) in a mild wet chemical process. The thickness of AL- β- Co(OH) 2 is less than 1.5 nm. It is the first time of using atom-layered β -Co(OH) 2 in the system of LOBs and this material shows outstanding catalytic performance. The AL- β -Co(OH) 2 nanosheets as electrocatalysts in LOBs can better reduce the over-potential, enhance the specific capacity and improve cycling capability. It demonstrates a high initial capacity 11841 mAh g −1 at a current density of 100 mA g −1 . It displays long cycle stability more than 70 cycles with a capacity restriction of 1000 mAh g −1 . These results suggest that this strategy for designing oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalysts via exfoliation of materials to atom-layered level could be a promising way to improve the performance of LOBs. [ABSTRACT FROM AUTHOR]

Classical methods for initial orbit determination (IOD) include Laplace method, Gauss method, and their variations. In addition to this, based on the characteristic of optical observation data nowadays, experts propose some other IOD methods, like Double- r method and admissible region method. One of the ways to determinate the orbit through double- r method is to guess distances of the target from the observer at two epochs—usually at the first and the last one. By doing so, we can solve the Lambert problem, and use its solution as the initial guess of the orbit. Furthermore, we can improve the initial guess by iterations to reduce the root mean square (RMS) of the observations. The admissible method is based on the concept of attributable (longitude, latitude, and their rates). With some conceptions, the admissible region described by the range and range rate from the observer is characterized. Using triangulation we can find the nodal point that makes the RMS minimal. In our work, we apply one intelligent optimization method—the particle swarm optimization method to the two methods, based on simulated and real data, and compare the results with that of modified Laplace method. At last, we briefly discuss the possibility of applying the double- r method to the orbit link problem. [ABSTRACT FROM AUTHOR]

In this study, thiolated magnetic iron oxide nanoparticles (Fe 3 O 4 -SH) were prepared and characterized in detail, which exhibited benign superparamagnetism and magnetic recoverability. And the adsorption and desorption processes for various heavy metals, including Pb 2+ , Ni 2+ , Zn 2+ and Cu 2+ , had been investigated comprehensively both in single and mixed systems using the Fe 3 O 4 -SH nanoparticles as adsorbents. The results showed that heavy metal ions could be removed rapidly depending on the complexation with the SH-groups on the Fe 3 O 4 -SH surface. Besides, the adsorption was all sensitive to pH and ionic strength while the nano-adsorbents had the highest adsorption capacity and rate for Ni 2+ according to the adsorption kinetics and thermodynamics. In addition, the corresponding competitive adsorption processes and desorption experiments reflected that Fe 3 O 4 -SH had the strongest affinity and adsorption selectivity for Pb 2+ , followed by Ni 2+ and finally by Cu 2+ and Zn 2+ . Generally, the present study might provide a serviceable direction for the future efforts towards the application of Fe 3 O 4 -SH nano-adsorbents in industrial wastewater treatments involving multiple heavy metal contaminants. [ABSTRACT FROM AUTHOR]

• Definition of new type 18 operator to enhance the model ability of GO methodology for MC(k,n) system. • Optimization of BN structure corresponding to large-scale MC(k,n) system. • Mapping procedure transforming GO model of MC(k,n) system to corresponding BN. • Fault diagnosis and improvement guidance of MC(k,n) system based on extended GO model and BN. As a success-oriented system reliability and safety analysis technique, GO methodology is widely used in the modeling and analysis scenarios of critical safety engineering systems with signal flow, such as nuclear, chemical industry, electric power transportation, wireless network and microwave communication network. Consecutive- k -out-of- n systems are also widely applied in these fields, but due to their relatively complex logic, there are no corresponding graphical modeling and calculation methods. In this paper, the basic GO methodology is extended to support the modeling and analysis of multi-state linear and circular consecutive- k -out-of- n : F system (MLC(k,n) &MCC(k,n)) models. Two new operators are defined in graphical modeling to represent the two types of complex system logic. The multi-state logic semantics of the new operators and mapping rules to Bayesian networks (BN) are given. And the programmable process is presented to transform the extended GO model into BN, and the reliability of the MLC(k,n)/MCC(k,n) is calculated. Finally, three cases are used to verify i) the correctness of the method supporting multi-state model, ii) the efficiency and ability of the algorithm, and iii) the forward calculation and reverse diagnosis of the MLC(k,n) and MCC(k,n) systems with external shared components. [ABSTRACT FROM AUTHOR]

Lactate dehydrogenase (LDH) catalyzes the interconversion of pyruvate and lactate, which are critical fuel metabolites of skeletal muscle particularly during exercise. However, the physiological relevance of LDH remains poorly understood. Here we show that Ldhb expression is induced by exercise inhumanmuscle and negatively correlated with changes in intramuscular pH levels, a marker of lactate production, during isometric exercise. We found that the expression of Ldhb is regulated by exerciseinduced peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α). Ldhb gene promoter reporter studies demonstrated that PGC-1α activates Ldhb gene expression through multiple conserved estrogen-related receptor (ERR) and myocyte enhancer factor 2 (MEF2) binding sites. Transgenic mice overexpressing Ldhb in muscle (muscle creatine kinase (MCK)- Ldhb) exhibited increased exercise performance and enhanced oxygen consumption during exercise. MCK-Ldhb muscle was shown to have enhanced mitochondrial enzyme activity and increased mitochondrial gene expression, suggesting an adaptive oxidative muscle transformation. In addition, mitochondrial respiration capacity was increased and lactate production decreased inMCK-Ldhbskeletal myotubes in culture. Together, these results identified a previously unrecognized Ldhb-driven alteration in muscle mitochondrial function and suggested a mechanism for the adaptive metabolic response induced by exercise training. [ABSTRACT FROM AUTHOR]

7-Hydroxymethyl chlorophyll a reductase (HCAR) catalyzes the second half-reaction in chlorophyll b to chlorophyll a conversion. HCAR is required for the degradation of light-harvesting complexes and is necessary for efficient photosynthesis by balancing the chlorophyll a/b ratio. Reduction of the hydroxymethyl group uses redox cofactors [4Fe-4S] cluster and FAD to transfer electrons and is difficult because of the strong carbonoxygen bond. Here, we report the crystal structure of Arabidopsis HCAR at 2.7-Å resolution and reveal that two [4Fe-4S] clusters and one FAD within a very short distance form a consecutive electron pathway to the substrate pocket. In vitro kinetic analysis confirms the ferredoxin-dependent electron transport chain, thus supporting a proton-activated electron transfer mechanism. HCAR resembles a partial reconstruction of an archaeal F420-reducing [NiFe] hydrogenase, which suggests a common mode of efficient proton-coupled electron transfer through conserved cofactor arrangements. Furthermore, the trimeric form ofHCARprovides a biological clue of its interaction with light-harvesting complex II. [ABSTRACT FROM AUTHOR]

The oxygen evolution reaction (OER) process involves the magnetic reversal of oxygen-containing intermediates, and the influence of defect structures on the magnetic behavior of catalysts might play a crucial role in this process. There is scarce research on the intrinsic relationship among defects, magnetism and catalysis. Herein, cation vacancy β -Ni(OH) 2 nanosheets were successfully prepared through alkaline selective etching. To further analyze their spin-magnetic behavior, we found that the presence of defects caused the transformation of Ni(OH) 2 from antiferromagnetic to ferromagnetic. Furthermore, to further elucidate their intrinsic spin-magnetic effects, it was observed that the initially antiferromagnetic β -Ni(OH) 2 exhibited almost no spin-magnetic response upon the introduction of a magnetic field, with the overpotential almost unchanged. Conversely, introducing defect structures showed a noticeable spin-magnetic effect, reducing the overpotential by 20 mV at 20 mA cm−2. The combination of defects and magnetic fields provides new principles for developing high-performance catalysts and understanding catalytic mechanisms at the spin-electronic level. • Ni 1-x Vac x (OH) 2 was prepared to investigate the spin-magnetic behavior of defect. • The defects of Ni(OH) 2 led to transformation from antiferromagnetic to ferromagnetic. • The spin-magnetic effect can reduce the overpotential by 20 mV at 20 mA cm−2. [ABSTRACT FROM AUTHOR]

Studies have found lower risk of childhood cancer among Asian children. We aim to characterize the recent incidence and incidence-trend of childhood cancer in Taiwan after the National Health Insurance program was launched in March 1995. Data were extracted from the Taiwan Cancer Registry, a population-based database established in 1979. Cases diagnosed at age 0-14 from 1996 to 2010 were analyzed and categorized according to the International Classification of Childhood Cancer, Third Edition (ICCC-3). In total, 8032 childhood cancer cases were included, with a microscopic verification rate of 93.9%. The overall age-standardized rate (ASR) of incidence adjusted to the 2000 World Standard Population is 125.0 cases/million, with a male-to-female ratio of 1.3. The top five cancer types (ICCC-3 subgroup[s]; ASR per million) are acute lymphoblastic leukemia (Ia, 30.3), acute myeloid leukemia (Ib; 9.4), non-Hodgkin lymphoma (IIb,c,e, 9.0), extracranial germ cell tumor (Xb,c; 8.3), and neuroblastoma (IVa; 7.8). The median age of diagnosis was 6 years for both genders. During the study period, the ASR of childhood cancer has been increasing at a rate of 1.2% per year (95% confidence interval, 0.6-1.7%). In contrast to Western countries, China, Japan, and Taiwan have lower incidence of childhood cancer; however, Taiwan's incidence rates of childhood germ cell tumors and hepatic tumors are higher. In conclusion, this population-based study reveals that the incidence rate of childhood cancer in Taiwan is rising consistently. The high incidence of germ cell tumors warrants further investigation. [ABSTRACT FROM AUTHOR]

The formation of a SEI layer and its growth cause internal resistance increase and capacity loss, leading to performance degradation of lithium-ion batteries. In order to comprehensively investigate the effects of SEI growth on battery performance, a one-dimensional thermal-electrochemical model was developed. This model is equipped with a growth mechanism of the SEI layer coupled with thermal evolution, based on the diffusional process of the solvent through the SEI layer and the kinetic process at the interface between the solid and liquid phases. The model is able to reveal the effects of diffusivity, reaction kinetics and temperature on SEI layer growth and cell capacity fade. We show that depending on the SEI thickness, the growth can be kinetics-limited or diffusion-limited. With the layer becoming thicker, its growth rate slows down gradually due to increased diffusion resistance. The SEI layer grows faster during charge than discharge due to the difference in the electron flux through the SEI layer and the temperature change during cycling. Temperature rise due to reaction and joule heating accelerates the SEI layer growth, leading to more capacity loss. Our model can provide insights on position-dependent SEI growth rate and be used to guide the strategic monitoring location. [ABSTRACT FROM AUTHOR]

The author used an eye-tracking methodology to examine the influence of the concept-mapping learning strategy on learners performing an English reading task. Eighty-six freshmen enrolled in English courses participated in this control-group pretest-posttest experiment, and received either traditional or concept-mapping instruction for learning English reading skills. A concept-mapping strategy was introduced to the learners in the experimental group to improve their reading ability. The results of independent t tests, in which eye-tracking data on fixation time and fixation path were used, indicated that the participants who received concept-mapping instruction exhibited shorter fixation times on the core concept and other content in the text, compared with the group that received traditional instruction. Moreover, the experimental group demonstrated longer and irregular rereading paths than the control group (CG) did. These results indicated that concept mapping serves as a reference to assist average readers to improve and to identify primary ideas that clarify the meaning of an article. [ABSTRACT FROM AUTHOR]

In the optical multicast network, node and link failures have very important influence on the network survivability which may lead to multiple destinations cannot receive data. Based on the wavelength layered-graph method, a method of efficiency-score based on heuristic algorithm of pre-configured cycle (p-Cycle) based-segment protection (ESHS) for dynamic multicast with limited-range wavelength conversion was presented in this paper. By finding the multicast tree segment protection, the total available p-Cycles are constructed for the multicast. Then we calculate each p-Cycle efficiency-score, the highest efficient-score p-Cycle is selected as the multicast route protection p-Cycle. The simulation results show that the ESHS can get higher performance than the existing ESHT algorithm, in terms of multicast request blocking probability and wavelength utilization. [ABSTRACT FROM AUTHOR]

Four pilot-scale constructed wetlands (free water surface, SF; horizontal subsurface flow, HSF; vertical subsurface flows with different water level, VSF-L and VSF-H) were operated to assess their ability to remove sulfamethazine (SMZ) and tetracycline (TC) from wastewaters, and to investigate the abundance level of corresponding resistance genes (sulI, sulII, tetM, tetW and tetO) in the CWs. The results indicated that CWs could significantly reduce the concentration of antibiotics in wastewater, and the mass removal rate range of SMZ and TC were respectively 11%-95% and 85%-95% in the four systems on the basis of hydraulic equilibrium; further relatively high removal rate was observed in VSF with low water level. Seasonal condition had a significant effect on SMZ removal in the CWs (especially SMZ in SF), but TC removal in VSFs were not considered to have statistically significant differences in winter and summer. At the end period, the relative abundances of target genes in the CWs showed obvious increases compared to initial levels, ranging from 2.98 x 10-5 to 1.27 x 10-1 for sul genes and 4.68 x 10-6 to 1.54 x 10-1 for tet genes after treatment, and those abundances showed close relation to both characteristic of wastewater and configuration of CWs. [ABSTRACT FROM AUTHOR]

Mehrotra proposed a classical method for edge detection based on Gabor filter in 1992. He investigated the algorithm using the measures proposed by Canny and designed a criterion for one-dimensional (1-D) and two-dimensional (2-D) Gabor filter-based edge detector. The derivation was too complicated in time domain and it is not strict enough for 2-D step edge. We explain the Gabor filter-based edge detector by a more precise but much simpler mathematical derivation in frequency domain. [ABSTRACT FROM AUTHOR]

Achieving improved energy efficiency, a green economy and degradation of environmental pollutants are important challenges to achieving sustainable development strategies. Herein, we have designed and synthesized a series of LaFe 1-x O 3 (LaFeO 3 , LaFe 0.95 O 3 , and LaFe 0.9 O 3) crystals with Fe vacancies for photo-assisted electrocatalysis (PAEC). These catalysts are used for both the anodic and cathodic reactions, where the anode efficiently removes persistent organic pollutants such as methylene blue (MB), and the cathode converts water into hydrogen gas. We observed that the presence of Fe vacancies leads to rearranging the electronic structure on the surface, enhancing the photo-assisted electrocatalytic activity. The rate constant for the photo-assisted electrocatalytic LaFe 0.90 O 3 was measured to be 0.996 min−1, which is 2.37 times and 2.74 times higher than that of the electrocatalytic (0.420 min−1) and photocatalytic (0.363 min−1) processes, respectively. The hydrogen production efficiency reached 1.42 μmol min−1. This study provides the first evidence of the photo-assisted electrocatalytic mechanism and potential applications of LaFeO 3 -based catalysts in enhancing the electro-oxidation of pollutants. It offers additional insights for the rational design and construction of more efficient PAEC catalysts for effective wastewater purification and energy recovery. [Display omitted] • The photo-assisted electrocatalysis for LaFe 1-x O 3 has been demonstrated. • The LaFe 0.90 O 3 owned outstanding electrocatalytic and photocatalytic performance. • The presence of Fe vacancies can enhance photo-assisted electrocatalytic activity. [ABSTRACT FROM AUTHOR]

Streak cameras are widely used as ultrafast diagnostic tools in several research fields. With an increase in the complexity of the experiments being conducted, large-format streak cameras with high spatiotemporal resolution are required for wide-band, high-precision spectroscopic recording. This paper presents the design of a high-resolution large-format streak camera with a planar photocathode. To alleviate the effect of field curvature for a large-format photocathode and to improve its spatial resolution, a weak–strong double-focusing lens coupled with a spherical fluorescent screen is used. A high voltage is also used to reduce transit time dispersion in order to improve temporal resolution. Experimental results show that the minimum effective diameter of the planar photocathode is 40 mm, compare to the existing 30 mm photocathode, which can achieve a minimum spatial resolution of 1000 line pairs and a temporal resolution of approximately 4 ps. The dynamic spatial resolution achieved is 20 lp/mm and the deflection sensitivity is approximately 64 kV/mm. [ABSTRACT FROM AUTHOR]

Streak cameras are widely used as ultrafast diagnostic tools in several research fields as the spatiotemporal measurement is of great significance in physics, chemistry, and biomedical research. However, as action objects, electron beams inside streak tubes are easily affected by the surrounding environment, which may lead to deterioration in the performance. In this study, the influence of a geomagnetic field on a streak tube is verified through a simulation. Based on the simulation results, the variation in the image shape due to the geomagnetic field and the overall camera imaging characteristics are analysed theoretically for the first time. The experimental result demonstrates that the imaging characteristics are better after a theoretical analysis is conducted and the final image is adjusted according. We discuss how this analysis can further develop other types of electron optical imaging systems and experiments. [ABSTRACT FROM AUTHOR]

Mammalian Asn-linked glycans are extensively processed as they transit the secretory pathway to generate diverse glycans on cell surface and secreted glycoproteins. Additional modification of the glycan core by a-1,6-fucose addition to the innermost GlcNAc residue (core fucosylation) is catalyzed by an a-1,6-fucosyltransferase (FUT8). The importance of core fucosylation can be seen in the complex pathological phenotypes of FUT8 null mice, which display defects in cellular signaling, development, and subsequent neonatal lethality. Elevated core fucosylation has also been identified in several human cancers. However, the structural basis for FUT8 substrate specificity remains unknown. Here, using various crystal structures of FUT8 in complex with a donor substrate analog, and with four distinct glycan acceptors, we identify the molecular basis for FUT8 specificity and activity. The ordering of three active site loops corresponds to an increased occupancy for bound GDP, suggesting an induced-fit folding of the donor-binding subsite. Structures of the various acceptor complexes were compared with kinetic data on FUT8 active site mutants and with specificity data from a library of glycan acceptors to reveal how binding site complementarity and steric hindrance can tune substrate affinity. The FUT8 structure was also compared with other known fucosyltransferases to identify conserved and divergent structural features for donor and acceptor recognition and catalysis. These data provide insights into the evolution of modular templates for donor and acceptor recognition among GT-B fold glycosyltransferases in the synthesis of diverse glycan structures in biological systems. [ABSTRACT FROM AUTHOR]

Members of glycosyltransferase family 75 (GT75) not only reversibly catalyze the autoglycosylation of a conserved arginine residue with specific NDP-sugars but also exhibit NDPpyranose mutase activity that reversibly converts specific NDP-pyranose to NDP-furanose. The latter activity provides valuable NDP-furanosyl donors for glycosyltransferases and requires a divalent cation as a cofactor instead of FAD used by UDP-D-galactopyranose mutase. However, details of the mechanism for NDP-pyranose mutase activity are not clear. Here we report the first crystal structures of GT75 family NDPpyranose mutases. The novel structures of GT75 member MtdL in complex with Mn2+ and GDP, GDP-D-glucopyranose, GDPL-fucopyranose, GDP-L-fucofuranose, respectively, combined with site-directed mutagenesis studies, reveal key residues involved in Mn2+ coordination, substrate binding, and catalytic reactions. We also provide a possible catalytic mechanism for this unique type of NDP-pyranose mutase. Taken together, our results highlight key elements of an enzyme family important for furanose biosynthesis. [ABSTRACT FROM AUTHOR]

The genus Salmonella is responsible for many illnesses in humans and other vertebrate animals. We report here that Salmonella enterica serovar Typhimurium harbors three transketolases that support the non-oxidative branch of the pentose phosphate pathway. BLAST analysis identified two genes, STM14_2885 and STM14_2886, that together encode a putative transketolase (TktC) with 46-47% similarity to the known TktA and TktB isoforms. Assessing themRNAand protein expression for each of the three transketolases, we determined that all are expressed in WT cells and regulated to varying extents by the alternative sigma factor RpoS. Enzyme assays with lysates from WTand transketolase-knockout strains established that TktA is responsible for >88% of the transketolase activity in WT cells. We purified recombinant forms of each isoenzyme to assess the kinetics for canonical transketolase reactions. TktA and TktB had comparable values for Vmax (539-1362 µM NADH consumed/s), Km (80-739 µM), and catalytic efficiency (1.02 x 108-1.06 x 109 M-1/s) for each substrate tested. The recombinant form of TktC had lower Km values (23-120 µM), whereas the Vmax (7.8-16 µM NADH consumed/s) and catalytic efficiency (5.58 x 106 to 6.07 x 108 M-1/s) were 10-100-fold lower. Using a murine model of Salmonella infection, we showed that a strain lacking all three transketolases is avirulent in C57BL/6 mice. These data provide evidence that S. Typhimurium possesses three transketolases that contribute to pathogenesis. [ABSTRACT FROM AUTHOR]

Considerable research has been conducted on evaluating the effectiveness of land consolidation (LC). However, most of the previous studies dealt with such evaluation in the areas where LC has taken place, whereas few focused on the potential evaluation before LC is implemented. Furthermore, land fragmentation has critical effects on the effectiveness evaluation of LC, but is not appropriately measured by currently used landscape metrics in the potential evaluation since project zones of LC cannot be delimited before LC implementation. To fill these gaps, this study demonstrates a potential evaluation model for LC, in which land fragmentation is taken into account by buffering land parcels and then quantifying their contiguity with a proper method. This model was tested in a case study area – Yangshan County of Guangdong, China, and the results showed that the new model is more robust than the traditional approach that evaluates the potential of land parcels in LC in terms of their locations, quality, terrains, and distances to infrastructural facilities. Moreover, the model revealed that land fragmentation plays an important role in LC potential evaluation. These findings imply that the proposed method can provide more appropriate guidelines for land decision-makers. [ABSTRACT FROM AUTHOR]

Using Cu 2 O nanowires as sacrificial templates, SnO 2 nanotubes have been synthesized via wet chemical process. The morphology and the fine crystalline structure of the produced SnO 2 nanotubes have been characterized. None of any oxidizing agents or acid was added into the reaction system, which makes the mechanism much different from the known ones based on acidic or oxidative/redox etching of metal oxide templates. Accordingly one discusses the growth mechanism and attributes it to the hydrolysis of Sn 4+ , to form SnO 2 , and the coordination of CuCl with Cl − , to form soluble [CuClx] 1−x , eliminating Cu 2 O nanowires. [ABSTRACT FROM AUTHOR]

Aflatoxins are a series of highly toxic and carcinogenic secondary metabolites that are synthesized by Aspergillus species. The degradation of aflatoxin enzymes is an important regulatory mechanism which modulates mycotoxin producing. The retromer complex is responsible for the retrograde transport of specific biomolecules and the vacuolar fusion in the intracellular transport. Late endosomal-associated GTPase (Rab7) has been shown to be a downstream effector protein of the retromer complex. A deficiency in the retromer complex or Rab7 results in several cellular trafficking problems in yeast and humans, like protein abnormal accumulation. However, whether retromer dysfunction is involved in aflatoxin synthesis remains unclear. Here, we report that the core retromer complex, which comprises three vacuolar protein sortingassociated proteins (AflVps26-AflVps29-AflVps35), is essential for the development of dormant and resistant fungal forms such as conidia (asexual reproductive spore) and sclerotia (hardened fungal mycelium), as well as aflatoxin production and pathogenicity, in Aspergillus flavus. In particular, we show the AflVps26-AflVps29-AflVps35 complex is negatively correlated with aflatoxin exportation. Structural simulation, sitespecific mutagenesis, and coimmunoprecipitation experiments showed that interactions among AflVps26, AflVps29, and AflVps35 played crucial roles in the retromer complex executing its core functions. We further found an intrinsic connection between AflRab7 and the retromer involved in vesicle-vacuole fusion, which in turn affected the accumulation of aflatoxin synthesis-associated enzymes, suggesting that they work together to regulate the production of toxins. Overall, these results provide mechanistic insights that contribute to our understanding of the regulatory role of the core retromer complex in aflatoxin metabolism. [ABSTRACT FROM AUTHOR]

Fewer than 250 Asian elephants remain in China, occupying fragmented habitats of Yunnan Province. One such fragmented population of 18–23 individuals occupies the Nangunhe Nature Reserve Area in Lincang City, Yunnan Province, China. The greatest threat to the survival of this population is the loss and fragmentation of habitat. In this study, we applied an ecological niche factor analysis (ENFA) model to evaluate the habitat suitability of Lincang City for Asian elephants based on geographical factors, vegetation type, and human disturbance. Optimal, relatively suitable, and marginal habitat accounted for 0.16% (38.45 km 2 ), 0.61% (150.00 km 2 ), and 3.34% (817.26 km 2 ) of the total study area, whereas non-suitable habitat accounted for 95.89% (23,463.29 km 2 ) of this area. The marginality of Asian elephant habitat in Lincang was 1.954, indicating nonrandom selection of various eco-geographical variables in the environment. The primary factor affecting Asian elephant habitat quality was vegetation type, followed by geographical factors and human disturbance. A habitat quality map for the total distribution of Asian elephants remaining in China (i.e., Yunnan Province: Xishuangbanna, Lincang, and Pu'er) based on our current and previous study showed that just 1400.57 km 2 and 2689.62 km 2 relatively suitable and optimal habitat is available, owing to significant deforestation. In addition to reintroduction programs, conservation strategies should focus on improving the quality of marginal habitats for elephants, in parallel to placing ecological corridors through non-suitable habitat to connect all suitable habitats for this and other extremely small elephant populations in China to reduce genetic isolation and secure long-term survival for the species. [ABSTRACT FROM AUTHOR]

The Golgi enzyme UDP-GlcNAc:lysosomal enzymeN-acetylglucosamine- 1-phosphotransferase (GlcNAc-1-phosphotransferase), an α2β2γ2 hexamer, mediates the initial step in the addition of the mannose 6-phosphate targeting signal on newly synthesized lysosomal enzymes. This tag serves to direct the lysosomal enzymes to lysosomes. A key property of GlcNAc-1-phosphotransferase is its unique ability to distinguish the 60 or so lysosomal enzymes from the numerous nonlysosomal glycoproteins with identical Asn-linked glycans. In this study, we demonstrate that the two Notch repeat modules and the DNA methyltransferase-associated protein interaction domain of the αsubunit are key components of this recognition process. Importantly, different combinations of these domains are involved in binding to individual lysosomal enzymes. This study also identifies the γ-binding site on the α subunit and demonstrates that in the majority of instances the mannose 6-phosphate receptor homology domain of the γ subunit is required for optimal phosphorylation. These findings serve to explain how GlcNAc-1-phosphotransferase recognizes a large number of proteins that lack a common structural motif. [ABSTRACT FROM AUTHOR]

Although aspirin resistance is well reported in CVD, little is known about aspirin response in elderly patients with hyperhomocysteinaemia. The aim of the present study was to explore the prevalence of aspirin resistance in elderly patients with CVD and hyperhomocysteinaemia. A total of 370 elderly patients with CVD were recruited. The study included 216 patients with hyperhomocysteinaemia and 154 patients with normohomocysteinaemia receiving daily aspirin therapy (≥75 mg) over 1 month. The effect of aspirin was assessed using by light transmission aggregometry (LTA). Aspirin resistance was defined as ≥20% arachidonic acid induced aggregation according to LTA. Aspirin resistance was defined in 48 (13.0%) of 370 patients. The prevalence of aspirin resistance was higher in hyperhomocysteinaemic patients than normohomocysteinaemic patients (16.7% vs. 7.8%, odds ratio (OR) = 2.367; 95% confidence interval (CI) = 1.188-4.715, p = 0.012). In the multivariate logistic regression analysis, hyperhomocysteinaemia (OR = 2.406, 95% CI = 1.201-4.820, p = 0.013) was a significant risk factor for aspirin resistance. A significant number of CVD patients with hyperhomocysteinemia are resistant to aspirin therapy. Hyperhomocysteinemia is a significant risk factor for aspirin resistance in elderly patients with CVD. [ABSTRACT FROM AUTHOR]

Abstract In this work, hierarchically porous Cu doped Cu 2 O/reduced graphene oxide/cellulose (Cu@Cu 2 O/RGO/CE) hybrid catalysts were facilely prepared by in-suit deposition of Cu 2 O nanoparticles on 3D graphene oxide/cellulose (GO/CE) aerogels. The morphology, structure, optical properties, and photocatalytic performances of the resultant Cu@Cu 2 O/RGO/CE hybrid catalysts were investigated systematically. GO uniformly dispersed in cellulose matrix and induced the formation of homogeneous GO/CE hydrogels. And highly uniform octahedral Cu doped Cu 2 O nanoparticles anchored on the pore wall of the GO/CE aerogels without aggregation. The photocatalytic activity of Cu@Cu 2 O/RGO/CE hybrid catalysts for methyl orange (MO) was 2 times high to that of Cu 2 O/CE under visible light. This high photocatalytic activity of Cu@Cu 2 O/RGO/CE hybrid catalysts mainly derived from its specific hierarchical porous structure and hybrid phase compositions which were responsible for enhanced light harvesting, abundant catalytic active sites, excellent mass and electron transfer ability. Moreover, the Cu@Cu 2 O/RGO/CE hybrid catalysts could easily be recycled from aqueous solution and exhibited superior stability in cycle experiments. The main active species were detected to be. O 2 −,. OH and holes under visible light irradiation. Thus, this work provides a facile approach for preparing high-efficiency and easy recoverable photocatalysts, but also a promising technology for organic pollutant degradation. [ABSTRACT FROM AUTHOR]

Novel architectured porous Cu@Cu 2 O hybrid microspheres were successfully designed and synthesized using silk sericin (SS) as structure-director to firstly form the hierarchical Cu 2 O/SS microspheres by self-assembly, followed by a calcination process. A possible mechanism has been proposed based on the results of FESEM, TEM and XRD analysis. The photocatalytic performance of obtained porous Cu@Cu 2 O hybrid microspheres was investigated, and the synergistic effect of Cu and Cu 2 O phases contributed to improving the light absorption ability, electron-hole separation and transfer compared with pure Cu 2 O. Importantly, the photo-degradation ratio of Cu@Cu 2 O hybrid microspheres for methyl orange (MO) reached up to 99.9% after 110 min visible light irradiation, which is almost 1.3 times than that of pure Cu 2 O. Furthermore, Cu@Cu 2 O hybrid microspheres also exhibited outstanding reusability and stability because that its degradation efficiency for MO still maintained at 93.5% after five cycles. [ABSTRACT FROM AUTHOR]

[Display omitted] • Chemically stable dual-methylpipieridinium crosslinker was confirmed. • The QBNTP-MP11 AEM showed excellent conductivity and toughness. • The QBNTP-MP11 AEM displayed outstanding durability. • The BNTP-MP11 AEM exhibited high fuel cell and water electrolysis performance. A series of novel crosslinked poly(binaphthyl-co-terphenyl piperidinium)s (QBNTPs) based on various dual-piperidinium crosslinkers are designed and prepared as anion exchange membranes (AEMs) for alkaline fuel cells and water electrolysis. The excellent alkaline stability of the dual-piperidinium crosslinker with methyl substituent on the C4-position of the piperidinium ring is first confirmed. The as-prepared dual-methylpiperidinium crosslinked poly(binaphthyl-co-terphenyl piperidinium) (QBNTP-MP11) AEM shows an exceptional OH− conductivity (181.2 mS cm−1) and a suppressed swelling ratio (19.7%) at 90 °C. QBNTP-MP11 also exhibits a superior toughness (6.08 MJ m−3) and a marked storage modulus (6.52 × 106 Pa). Additionally, having less than 5% OH− conductivity deterioration after being treated in 2 M NaOH at 80 °C for 1560 h, QBNTP-MP11 demonstrates an outstanding durability. Notably, QBNTP-MP11 can achieve a high peak powder density of 1.41 W cm−2 in a single cell test and an excellent current density of 2.7 A cm−2 at 2.0 V in alkaline water electrolysis. Meanwhile, QBNTP-MP11 demonstrates a desirable durability in a single cell operation and water electrolysis. All those results validate that the durable and robust QBNTP-MP11 has a good application perspective. The work is anticipated to provide a valuable guidance for the design of new stable and high-performance AEMs. [ABSTRACT FROM AUTHOR]

Alkaline stability is the critical issue for the practical application of anion exchange membranes (AEMs) in fuel cells. The benzyltrimethyl ammonium and backbone with C-O linkages of the traditional AEMs are susceptible to attack by hydroxide ions resulting in poor alkaline stability of the AEMs. Herein, we present the preparation of polystyrene-b-poly(ethylene-co-butylene)-b-polystyrene (SEBS) triblock copolymer via grafting, ketone reduction and quaternization for AEM fuel cell applications. The quaternary ammonium (QA) groups are attached to the SEBS backbone free of C-O linkages via long flexible alkyl spacers, which are responsible for the robust alkaline stability of the AEMs. Thus, the hydroxide conductivity of SEBS-CH 2 -QA-1.5 was only decreased by 7.7% and 13.7% after immersing the membranes into a 1 M aqueous KOH solution at 60 and 90 °C for 360 h, respectively. Furthermore, SEBS-CH 2 -QA-1.5 with IEC of 1.23 meq g −1 exhibits a maximum hydroxide conductivity of 56.4 mS cm −1 at 80 °C and a maximum power density of 94.6 mW cm −2 under a current density of 300 mA cm −2 . [ABSTRACT FROM AUTHOR]

Aberrant proliferation and activation of lung fibroblasts contribute to the initiation and progression of idiopathic pulmonary fibrosis (IPF). However, the mechanisms responsible for the proliferation and activation of fibroblasts are not fully understood. The objective of this study was to investigate the role of miR-101 in the proliferation and activation of lung fibroblasts. miR-101 expression was determined in lung tissues from patients with IPF and mice with bleomycin-induced pulmonary fibrosis. The regulation of miR-101 and cellular signaling was investigated in pulmonary fibroblasts in vitro. The role of miR-101 in pulmonary fibrosis in vivo was studied using adenovirus-mediated gene transfer in mice. The expression of miR-101 was down-regulated in fibrotic lungs from patients with IPF and bleomycin-treated mice. The down-regulation of miR-101 occurred via the E26 transformation-specific (ETS) transcription factor. miR-101 suppressed the WNT5a-induced proliferation of lung fibroblasts by inhibiting NFATc2 signaling via targeting Frizzled receptor 4/6 and the TGF-β-induced activation of lung fibroblasts by inhibition of SMAD2/3 signaling via targeting the TGF-β receptor 1. Adenovirus-mediated miR-101 gene transfer in the mouse lung attenuated bleomycin-induced lung fibrosis and improved lung function. Our data suggest that miR-101 is an anti-fibrotic microRNA and a potential therapeutic target for pulmonary fibrosis. [ABSTRACT FROM AUTHOR]

Introduction: Perceived social isolation (PSI) is associated with substantial morbidity and mortality. Social media platforms, commonly used by young adults, may offer an opportunity to ameliorate social isolation. This study assessed associations between social media use (SMU) and PSI among U.S. young adults.Methods: Participants were a nationally representative sample of 1,787 U.S. adults aged 19-32 years. They were recruited in October-November 2014 for a cross-sectional survey using a sampling frame that represented 97% of the U.S.Population: SMU was assessed using both time and frequency associated with use of 11 social media platforms, including Facebook, Twitter, Google+, YouTube, LinkedIn, Instagram, Pinterest, Tumblr, Vine, Snapchat, and Reddit. PSI was measured using the Patient-Reported Outcomes Measurement Information System scale. In 2015, ordered logistic regression was used to assess associations between SMU and SI while controlling for eight covariates.Results: In fully adjusted multivariable models that included survey weights, compared with those in the lowest quartile for SMU time, participants in the highest quartile had twice the odds of having greater PSI (AOR=2.0, 95% CI=1.4, 2.8). Similarly, compared with those in the lowest quartile, those in the highest quartile of SMU frequency had more than three times the odds of having greater PSI (AOR=3.4, 95% CI=2.3, 5.1). Associations were linear (p<0.001 for all), and results were robust to all sensitivity analyses.Conclusions: Young adults with high SMU seem to feel more socially isolated than their counterparts with lower SMU. Future research should focus on determining directionality and elucidating reasons for these associations. [ABSTRACT FROM AUTHOR]

This paper is focusing on the synthesis and characterization of poly-crystalline ZnS nanotubes. The ZnS@ZnO core/shell nanorods were formed by replacing O 2− ions with S 2− ions released by hydrolyzed thioacetamide assisted by ethylene glycol; then, ZnS@ZnO core/shell nanorods were etched with potassium hydroxide solution to remove the ZnO core. Elaborate characterizations were carried out to show the fine crystalline structure. The key factor of preparing poly-crystalline ZnS nanotubes is the control over the replacement process of O 2− ions by S 2− ions with the assistance of ethylene glycol to inherit the morphology of ZnO nanorods. [ABSTRACT FROM AUTHOR]

Background matching is an important way to camouflage and is widespread among animals. In the field, however, few studies have addressed background matching, and there has been no reported camouflage efficiency in freshwater turtles. Background matching and camouflage efficiency of the four-eyed turtle, Sacalia quadriocellata , among three microhabitat sections of Hezonggou stream were investigated by measuring carapace components of CIE L*a*b* (International Commission on Illumination; lightness, red/green and yellow/blue) color space, and scoring camouflage efficiency through the use of humans as predators. The results showed that the color difference (ΔE), lightness difference (Δ L * ), and chroma difference (Δ a * b * ) between carapace and the substrate background in midstream were significantly lower than that upstream and downstream, indicating that the four-eyed turtle carapace color most closely matched the substrate of midstream. In line with these findings, the camouflage efficiency was the best for the turtles that inhabit midstream. These results suggest that the four-eyed turtles may enhance camouflage efficiency by selecting microhabitat that best match their carapace color. This finding may explain the high population density of the four-eyed turtle in the midstream section of Hezonggou stream. To the best of our knowledge, this study is among the first to quantify camouflage of freshwater turtles in the wild, laying the groundwork to further study the function and mechanisms of turtle camouflage. [ABSTRACT FROM AUTHOR]

In this paper, we propose a feature learning method for handwritten Chinese character recognition (HCCR), called discriminative quadratic feature learning (DQFL). Based on original gradient direction feature representation, quadratic correlation between features is used to promote the feature dimensionality, then discriminative feature extraction (DFE) is used for dimensionality reduction. By combining dimensionality promotion and reduction, we can learn a much more discriminative and nonlinear feature representation, which can then boost the classification accuracy significantly. For dimensionality promotion, two types of correlation are exploited, namely, statistical correlation and spatial correlation. Statistical correlation is computed on multiple local feature vectors in different regions of the character image; while spatial correlation encodes the dependency between features of two positions. Feature correlation increases the dimensionality by over 40,000. DFE then reduces the dimensionality to less than 300 without losing discriminability. Classification is performed using nearest prototype classifier (NPC), modified quadratic discriminant function (MQDF) and discriminative learning quadratic discriminant function (DLQDF). In experiments on the CASIA-HWDB1.1 standard dataset, the proposed DQFL method improves the test accuracies of NPC, MQDF and DLQDF by 4.94%, 1.83%, and 1.82%, respectively. The test accuracy is further improved by training set expansion. On the ICDAR 2013 Chinese handwriting recognition competition dataset, the proposed DQFL+DLQDF classifier outperforms the best participating system based on deep convolutional neural network (CNN), while the test speed is much faster. [ABSTRACT FROM AUTHOR]

In this paper, the influence of the addition of Al2O3 particles on the microstructure and wear properties of Fe-based amorphous coatings prepared by high velocity oxygen fuel (HVOF) has been studied. The wear behaviors of the composite coatings were evaluated against Si3N4 in a pin-on-disk mode in air and in 3.5 wt.% NaCl solution. It was found that the Al2O3 particles were homogenously distributed in the amorphous matrix and the composite coatings exhibited improved wear resistance and reduced coefficient of friction (COF) in both air and wet conditions as compared to the monolithic amorphous coating. The composite coating reinforced with 20 wt.% Al2O3 particles exhibit the best wear performance, which, for example, has extremely low COF (< 0.2) and high wear resistance (2-3 times higher than monolithic amorphous coating). Detailed analysis on the worn surface indicated that the wear mechanism for the amorphous and composite coatings is similar and is dominated by oxidative delamination in air and by corrosion wear in 3.5% NaCl solution. The enhanced wear resistance is mainly attributed to the addition of Al2O3 particles which exhibit high hardness, good corrosion resistance and excellent chemical and thermal stability. [ABSTRACT FROM AUTHOR]

Polymers of intrinsic microporosity are attractive membrane materials for gas separation due to their high specific surface and microporous structure. PIM-1 being the most representative one shows extremely high permeability but moderate selectivity for CO 2 separation. In this study, the CO 2 selectivity of PIM-1 is remarkably enhanced via blending with polyethylene glycol (PEG). A series of PIM-1/PEG blended membranes are prepared for separation of CO 2 /N 2 , CO 2 /CH 4 by varying the molecular weight (MW) and content of PEG. Their structure and physicochemical properties are explicitly characterized including density, morphology and thermostability. The blended membranes have less d -spacing of packed chains than pure PIM-1. The pure gas permeabilities of CO 2 , N 2 and CH 4 are measured with varying MW and content of PEG. The PEG blend depresses gas permeability of the PIM-1 membrane but greatly improves the CO 2 selectivity, especially for CO 2 /CH 4 separation. The membranes with 2.5 wt% PEG at different MWs have excellent separation performance for CO 2 /CH 4 separation, which surmounts the 2008 upper bound line. Specifically the membrane with 3.5 wt% PEG of 20 kDa has the CO 2 permeability of 1952 barrer and CO 2 /CH 4 selectivity of 39.0 that is more than three times that of the pure PIM-1 membrane. The as-prepared PIM-1/PEG membranes have a great potential for CO 2 separation. [ABSTRACT FROM AUTHOR]

A novel type of graphene oxide (GO)/Nafion composite membrane is fabricated and used as a proton exchange membrane for direct methanol fuel cells (DMFCs) in this article. The membranes are prepared by depositing GO nanosheets on the surface of recast Nafion ® 117 via a layer-by-layer (LbL) procedure using 1, 4-phenyldiamine hydrochloride (PDHC) as the cross-linker. This approach prevents the GO nanosheets from dissolving in water and imparts the composite membranes a good stability. The methanol permeability of the composite membranes is lower than that of recast Nafion ® 117 measured under the same conditions. The composite membrane with 80-layered GO nanosheets exhibits a value of 6.7×10 −8 cm 2 s −1 at 30 °C, which is two orders of magnitude lower than that of recast Nafion ® 117. In addition, the relative selectivity of the composite membranes is 5 times higher than that of recast Nafion ® 117. The endurance time of the composite membranes in Fenton׳s reagent is 10 times longer than that of Nafion. Single cell evaluation using the composite membrane with 50-layered GO showed an open circuit voltage (OCV) of 0.67 V. A maximum power density of 64.38 mW cm −2 at a current density of 200 mA cm −2 can be achieved at 60 °C. [ABSTRACT FROM AUTHOR]

The tetratricopeptide repeat (TPR)-containing protein FLU is a negative regulator of chlorophyll biosynthesis in plants. It directly interacts through its TPR domain with glutamyl-tRNA reductase (GluTR), the rate-limiting enzyme in the formation of δ-aminolevulinic acid (ALA). Delineation of how FLU binds to GluTR is important for understanding the molecular basis for FLU-mediated repression of synthesis of ALA, the universal tetrapyrrole precursor. Here, we characterize the FLU-GluTR interaction by solving the crystal structures of the uncomplexed TPR domain of FLU (FLUTPR) at 1.45-Å resolution and the complex of the dimeric domain of GluTR bound to FLUTPR at 2.4-Å resolution. Three non-canonical TPR motifs of each FLUTPR form a concave surface and clamp the helix bundle in the C-terminal dimeric domain of GluTR. We demonstrate that a 2:2 FLUTPR-GluTR complex is the functional unit for FLU-mediated GluTR regulation and suggest that the formation of the FLU-GluTR complex prevents glutamyl-tRNA, the GluTR substrate, from binding with this enzyme. These results also provide insights into the spatial regulation of ALA synthesis by the membrane-located FLU protein. [ABSTRACT FROM AUTHOR]

Dental cone beam computed tomography (CBCT) provides high-resolution tomographic images and has been gradually used in clinical practice. Thus, it is important to examine the amount of radiation dose resulting from dental CBCT examinations. In this study, we developed an in-house anthropomorphic adult head phantom to evaluate the level of effective dose. The anthropomorphic phantom was made of acrylic and filled with plaster to replace the bony tissue. The contour of the head was extracted from a set of adult computed tomography (CT) images. Different combinations of the scanning parameters of CBCT were applied. Thermoluminescent dosimeters (TLDs) were used to measure the absorbed doses at 19 locations in the head and neck regions. The effective doses measured using the proposed phantom at 65, 75, and 85 kVp in the D-mode were 72.23, 100.31, and 134.29 μSv, respectively. In the I-mode, the effective doses were 108.24, 190.99, and 246.48 μSv, respectively. The maximum percent error between the doses measured by the proposed phantom and the Rando phantom was l4.90%. Therefore, the proposed anthropomorphic adult head phantom is applicable for assessing the radiation dose resulting from clinical dental CBCT. [ABSTRACT FROM AUTHOR]

Flower-like ZnS or ZnS:Cu2+ nanostructures were prepared in aqueous solution via H2S diffusion procedure. The morphology of products can be controlled by adjusting the growth time or concentration of Cu2+. A bit of Wurtzite phase attributed to the high surface energy has been found with X-ray diffraction. The strong photoluminescence emission centered at 368nm. XRD, HR-TEM, EDS map and FTIR all confirm that Cu2+ was doped in ZnS lattice. [ABSTRACT FROM AUTHOR]

KDP crystals were grown by the "point seed" rapid growth technique from aqueous solutions with different organic additives, including NTA, HEDTA, EDTA and DCTA. The growth rates were up to about 20 mm/day. The influences of these organic additives on the growth habit and optical properties of these as-grown KDP crystals have been studied. Such organic additives were all found to be able to enhance the solution stability and promote the growth rate for the (100) face of KDP crystals. Furthermore, the UV transmittance and laser damage threshold of the KDP crystals were both increased with the addition of these organic additives. It is proposed that the beneficial influences are due to the chelating action of such organic additives with metal ion impurities in the growth solutions. [ABSTRACT FROM AUTHOR]

Urinary trichloroacetic acid (TCAA) and baseline blood trihalomethanes (THMs) have been measured as biomarkers of exposure to drinking water disinfection by-products (DBPs) that have been associated with increased risk of cancers and adverse reproductive outcomes. This study aimed to identify predictors of urinary TCAA and baseline blood THMs among men in China. Urine samples, blood samples, and information on socio-demographic factors and water-use activities were collected from 2216 men who participated in a cross-sectional study of exposure to drinking water DBPs and reproductive health during 2011 to 2012. Urinary TCAA and baseline blood THMs including chloroform (TCM), bromodichloromethane (BDCM), dibromochloromethane (DBCM), and bromoform (TBM) were analyzed. Multivariable linear regression was used to evaluate predictors of urinary TCAA and baseline blood THM concentrations. Tap water consumption was significantly associated with creatinine-adjusted urinary TCAA concentration (β = 0.23 µg/g creatinine per log10 unit; 95% CI: 0.12, 0.35). Men with surface water source had 0.13 (95% CI: 0.00, 0.27) higher mean creatinine-adjusted urinary TCAA concentrations than those with ground water source. Smoking was associated with lower concentration of creatinine-adjusted urinary TCAA. Age was significantly associated with baseline blood Br-THM (sum of BDCM, DBCM, and TBM) concentration (β = 0.01 ng/L per unit; 95% CI: 0.00, 0.02). Increased household income was associated with decreased concentrations of baseline blood BDCM and Br-THMs. Our results suggest that tap water consumption, water source, smoking, age, and household income as the primary determinants of exposure to drinking water DBPs should be considered in exposure assessment. [ABSTRACT FROM AUTHOR]

Magnesium protoporphyrin IX O-methyltransferase (ChlM) catalyzes transfer of the methyl group from S-adenosylmethionine to the carboxyl group of the C13 propionate side chain of magnesium protoporphyrin IX. This reaction is the second committed step in chlorophyll biosynthesis from protoporphyrin IX. Here we report the crystal structures of ChlM from the cyanobacterium Synechocystis sp. PCC 6803 in complex with S-adenosylmethionine and S-adenosylhomocysteine at resolutions of 1.6 and 1.7 Å, respectively. The structures illustrate the molecular basis for cofactor and substrate binding and suggest that conformational changes of the two "arm" regions may modulate binding and release of substrates/products to and from the active site. Tyr-28 and His- 139 were identified to play essential roles for methyl transfer reaction but are not indispensable for cofactor/substrate binding. Based on these structural and functional findings, a catalytic model is proposed. [ABSTRACT FROM AUTHOR]