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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]

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]

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]

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]

Mantle-derived spinel peridotite and spinel plagioclase pyroxenite xenoliths hosted in Cenozoic alkali basalts (20 Ma) are found in the Xikeer area, western Tarim Block, NW China. Based on petrographic and geochemical characteristics, the peridotite xenoliths are divided into three groups. Group 1 peridotite xenoliths have experienced high degree melt extraction (~ 17% fractional melting) and weak, incipient metasomatism. Group 2 and 3 peridotite xenoliths have undergone extensive silicate melt metasomatism, resulting in clinopyroxenes with spoon-shaped and highly fractionated REE patterns respectively. Although their present texture is metamorphic, the pyroxenite xenoliths were initially of metasomatic origin, with high pressure protolith mineral assemblage of orthopyroxene + clinopyroxene + spinel ± olivine. Numerical modeling of the Mg-number shows that the Xikeer pyroxenites may have resulted from reaction between Group 1 peridotite and a primitive Permian picritic melt at a high melt/rock ratio (> 15) and that the host basanite is incapable of being the metasomatic melt. The Re-Os isotopic systematics of the Xikeer peridotites and pyroxenites yield an apparent isochron of ~ 290 Ma, virtually identical to the age of Tarim flood basalts. Their εNd(t = 290 Ma) ranges from + 9.5 to + 14.3, typical of convecting mantle. We propose that the Xikeer xenolith suite may have been initially formed by melt extraction from the convecting mantle and, shortly after, was refertilized by Tarim mantle plume melts during the Early Permian, a process which is referred to as mantle 'auto-refertilization'. [ABSTRACT FROM AUTHOR]

A series of novel 2,6-conjugated Bodipy metal-free organic dyes (UY5-8) with phenothiazine (PTZ) moiety as electron donor for the dye-sensitized solar cells (DSSCs) have been designed and synthesized. The optical, electrochemical properties and photovoltaic performances are extensively investigated. The structure-property relationship shows that the introduction of various auxiliary conjugated spacers and anchoring groups are favorable to changing the efficiency of DSSCs. Among these dyes, UY7 comprised of furan with lower resonance energy as linker and cyanoacetic acid unit as electron acceptor possesses a flatter structure and longer electron recombination lifetime. Hence, a DSSCs using UY7 showing best photovoltaic performance with a short-circuit photocurrent density (Jsc) of 13.64mAcm-2, an open-circuit photovoltage (Voc) of 590mV and a fill factor (ff) of 0.66, corresponding to an overall conversion efficiency (η) of 5.31% under 100mWcm-2 simulated AM 1.5 G solar irradiation. This is the best reported result in the solar cell with a Bodipy dye as photosensitizer. [ABSTRACT FROM AUTHOR]

In solar cell technology, surface texturing is essential for reducing the reflectance of cell surfaces and increasing their efficiency. This study employs photo-assisted electrochemical etching (PAECE) to fabricate a hybrid structure comprising a reversed pyramid structure and a high aspect ratio macro-pore on the silicon wafer surface, to reduce cell surface reflectance. The experimental results show that the etching depth of the fabricated macro-pore array structure was approximately 67.1µm and its diameter was approximately 5µm on the 525-µm-thick sample, such that the aspect ratio of the pore was approximately 13.4:1. The mean reflectance of a blank silicon wafer is 37.4% in the wavelength range of 280-800nm; however, the reversed pyramid created using a 120-min PAECE process and 25-min RIE can reduce the mean reflectance to 0.7% on the 380-µm-thick sample. The novel fabrication process developed in this study is low cost and the hybrid structure can be applied to antireflection structures in single crystalline silicon solar cells. [ABSTRACT FROM AUTHOR]

In this study, a new process was proposed to enhance the stability and efficiency of an anaerobic baffled reactor (ABR). The process was examined in a four equal compartments ABR with total volume of 3.46 L. The first compartment was operated for fermentative hydrogen production and the last three compartments were used as continuous singer chamber microbial electrolysis cells (MECs) for methanogenesis. The system was operated at 35 ± 1 °C and hydraulic retention time (HRT) of 24 h with influent chemical oxygen demand (COD) concentration of 3500 mg/L–4000 mg/L. The results indicated that the proportion of hydrogen in the first compartment was 20.7% and proportions of methane in the last three compartments were 98.0%, 93.6% and 70.1%, respectively. A total of 98.0% of COD removal rate was achieved as well. Hence, this new system has following advantages: hydrogen production with cleaner effluent, high COD removal rate, and net methane production for practical use. [ABSTRACT FROM AUTHOR]