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The rational fabrication of heterostructures is one of efficient strategies for improving photocatalytic performance of semiconductor photocatalysts. Very recently, Domen and co-workers found that Ta3N5 single crystals grown on the surface of KTaO3 can accomplish photocatalytic overall water splitting for the first time. In order to comprehend the underlying mechanism of this photocatalytic system, we have performed a systematic study based on density functional theory first-principles calculations. Ta3N5(010)/KTaO3(110) slab models have been built according to experimental observations by considering two common terminations of KTaO3(110) surface, named as Ta3N5/O2 and Ta3N5/KTaO. The formations of interfacial bonds are thermodynamically stable, showing a covalent interaction between two components of a heterostructure. Ta3N5/O2 has a higher mobility of photogenerated charge carriers and lower recombination rate of charge carriers than Ta3N5/KTaO. The light absorption of heterostructures displays the feature of KTaO3 in the short wavelength region and the characteristic of Ta3N5 in the long wavelength region. The calculated band offsets show that Ta3N5/O2 and Ta3N5/KTaO have distinct Type-II band alignments, with Ta3N5 as the accumulator of photoinduced electrons in the former and the collector of photogenerated holes in the latter, respectively. The difference in charge density and electrostatic potential between two components acts as a driving force to promote the transfer of electrons and holes to different domains of the interface, which is beneficial to extend the lifetime of photoinduced carriers. Our results demonstrate that the function of Ta3N5 in Ta3N5/KTaO3 photocatalytic system is determined by the termination property of KTaO3(110) surface, which provides a likely reason of the observed photocatalytic activity of overall water splitting achieved by Ta3N5 synthesized by using KTaO3 as a precursor for the nitridation reaction.

New energy vehicles (NEVs) are welcomed by both policymakers and consumers because of their energy saving and low carbon properties. However, due to their high production cost and limited cruising range, the development of the NEV industry relies heavily on governments’ cash subsidy (CS) programs. At the same time, policymakers in several countries, including the United States (California) and China, have introduced carbon regulation (CR) to re-energize the NEV market. CS and CR have different impacts on the consumer and production sides. To this end, we propose a hybrid model combining the advantages of both. Through this model, the impacts of different interventions on product demands, profits, carbon emissions and technology RD providing CS increases the profits of the supply chain members, but supply chain profits under CR show uncertain trends; (2) CS reduces total emissions only if the unit carbon emission of NEVs is small enough, and the effect of NEVs’ carbon quota on total emissions under CR shows a similar trend, whereas the impact of carbon price on total emissions under CR depends on specific thresholds. Further results show that when a customer values NEVs highly, the proposed hybrid model produces the lowest total emission; (3) Optimal technology RD otherwise, CR performs better. The hybrid model shows potential in outperforming the other two policies in terms of the optimal technology RD (4) Supply chain integration decreases the optimal technology R&D in the case of CR, whereas in the case of CS, technology R&D does not vary with integration or decentralization of the supply chain.

Emerging markets have created significant opportunities for European small- and medium-sized enterprises (SMEs). Highly dissimilar market contexts compared to traditional markets and missing resources present substantial barriers to successfully serve those markets. Collaborative partnerships with local SMEs can help to overcome the barriers. Knowledge on how SMEs can develop lasting collaborative relationships in highly dissimilar contexts is scarce. This research investigates which factors influence the stability of more informal collaborative partnerships of Central European SMEs with SMEs located in China. A qualitative analysis of four cases confirms the importance of complementarity of partner resources, working well together based on mutual trust and commitment, shared sensemaking, and the balanced consideration of partner interests. Mutual learning and adaptation in iterative steps to enhance shared sensemaking and seeing differences in interpretation and behavior arising from contextual dissimilarity as opportunities instead of threats turn out to be SME-specific factors essential for building stable informal collaborative relations.

Biochar has been increasingly applied in constructed wetlands (CWs) to remediate heavy metal (HM)-polluted water. Nevertheless, only few studies have elucidated the enhanced mechanism and potential synergies related to the HM removal from biochar-based CWs (BC-CWs) for HMs removal. This study used cadmium (Cd) as the target HM and added biochar into CWs to monitor physicochemical parameters, plant' physiological responses, substrate accumulation, and microbial metabolites and taxa. In comparison with the biochar-free CW (as CWC), a maximum Cd

A self-supporting electrode (FeCo-MOF/CNFs) combining iron cobalt bimetallic metal-organic frameworks (FeCo-MOFs) with carbon nanofibers (CNFs) was applied as the anode of a microbial fuel cell (MFC). The introduction of FeCo-MOFs enhanced graphitization degree and electrical conductivity, which endowed FeCo-MOF/CNFs with excellent electrocatalytic performance and good biocompatibility. The hierarchical porous structure of FeCo-MOF/CNFs provided abundant attachment sites for electroactive bacteria (EAB) and facilitated rapid electron transfer. The MFC equipped with FeCo-MOF/CNFs anode (FeCo/CNFs-MFC) exhibited considerable power generation output (maximum power density: 5.3 ± 0.2 W/m

Bacillus subtilis, a spore-forming industrial bacterium, is widely used for production of enzymes and valuable chemicals. The spore-formation, however, always results in remarkably reduced cell-density, thereby reducing product yield. Here, we constructed different non-spore-forming B. subtilis mutants via single-gene regulation. During the three spore-forming stages: signal sensing, transduction, and sporulation, we found that deleting only a single gene of sporulation, i.e. spo0A, spoIIIE, and spoIVB, can completely block the spore generation. Interestingly, the engineered non-sporulating mutants exhibited physiological heterogeneity and distinct synthetic capabilities. The spo0A-null spore-free mutant displayed remarkably high enzyme production capacity, such as 194% enhance amylase production. However, the spoIVB-null non-spore-forming mutant was especially efficient in producing secondary metabolites, such as surfactin; its flask titer increased significantly to 16.7 g/L, with the overexpression and Leu addition strategy. Our results offer a new strategy for re-modeling B. subtilis to further improve its fermentation efficiency and application.

Pulmonary fibrosis has been characterized by abnormal proliferation of fibroblasts and massive deposition of the extracellular matrix, which results from a complex interplay of chronic injury and inflammatory responses. MicroRNA-301a (miR-301a) is activated by multiple inflammatory stimulators, contributing to multiple tumorigenesis and autoimmune diseases. This study showed that miR-301a was overexpressed in a bleomycin-induced murine model of pulmonary fibrosis and patients with idiopathic pulmonary fibrosis (IPF). In addition, miR-301a was activated by transforming growth factor β (TGF-β) and interleukin 6 (IL-6) in normal and IPF fibroblasts, which was markedly reversed by the signal transducer and activator of transcription 3 (STAT3) inhibitor. The genetic ablation of miR-301a in mice reduced bleomycin-induced lung fibrosis, and the downregulation of miR-301a restrained proliferation and activation of fibroblasts. Furthermore, this study demonstrated that TSC1 was a functional target of miR-301a in fibroblasts, and the negative regulation of TSC1 by miR-301a promoted the severity of pulmonary fibrosis through the mammalian target of rapamycin (mTOR) signaling pathway. The blocking of miR-301a by the intravenous injection of antagomiR-301a inhibited the proliferation of fibroblasts and the structural destruction of lung tissues in the bleomycin-induced lung fibrosis mouse model. The findings revealed the crucial role of the miR-301a/TSC1/mTOR axis in the pathogenesis of pulmonary fibrosis, suggesting that miR-301a might serve as a potential therapeutic target., Graphical Abstract, Abnormal activation of fibroblasts is the key event of pulmonary fibrosis. In this study, Want et al. reported that miR-301a deficiency protects against bleomycin-induced fibrosis in mice by inhibiting the activation of fibroblasts. The findings also revealed a significant role for the miR-301a/TSC1/mTOR axis in pulmonary fibrosis.

β-Ge3N4 loaded with nanoparticulate RuO2 as a cocatalyst is the first successful non-oxide photocatalyst for overall water splitting. To get an insight into the working mechanism of this particular photocatalytic system, we have calculated geometrical structures of low-index surfaces for β-Ge3N4. Analysis of surface energies indicates that the most preferentially exposed surface is (100). The band gap of surface is narrower than that of bulk due to the dangling bonds. Dissociative water adsorption on (100) surface is thermodynamically favorable. The adsorption behavior of (RuO2)n (n = 2, 3, and 4) clusters on the β-Ge3N4(100) surface has been explored. It is found that all the clusters bind to (100) surface strongly by forming interfacial bonds so that the adsorptions are exothermic processes. The calculation on density of states for β-Ge3N4(100) surface loaded with (RuO2)n clusters reveals that photo-induced electrons tend to accumulate on (RuO2)n clusters and holes tend to stay in β-Ge3N4. Based on the theoretical indication of Type-II staggered band alignment, we have proposed that in photocatalytic water splitting reaction, oxygen evolution reaction is inclined to occur on the surface of β-Ge3N4 while hydrogen evolution reaction is apt to occur on (RuO2)n clusters. In a word, loading RuO2 nanoparticles as a reduction cocatalyst benefits the charge separation in β-Ge3N4. Furthermore, attaching (RuO2)n clusters onto β-Ge3N4(100) surface results in the redshift of absorption edge and the increase of absorption intensity. Our calculations have reasonably explained the experimental observation on the decomposition of water into H2 and O2 after loading RuO2 cocatalyst in β-Ge3N4 photocatalyst.

We tested the hypothesis that maternal perinatal serum levels of poly and perfluoroalkyl substances (PFASs) predict risk for breast cancer in daughters in a 54-year follow-up of 9300 daughters born 1959-1967 in the Child Health and Development Studies pregnancy cohort. Total cholesterol and PFASs were measured in archived maternal perinatal serum for 102 daughter breast cancer cases diagnosed by age 52, and 310 controls matched on birth year and blood draw trimester. High maternal N-ethyl-perfluorooctane sulfonamido acetic acid (EtFOSAA), a precursor of perfluorooctane sulfonic acid (PFOS), in combination with high maternal total cholesterol predicted a 3.6-fold increased risk of breast cancer (pinteraction

In this work, the adequacy check of errors-in-variables varying-coefficient models is investigated when replicate measurements are available. Estimation using the naive method that ignores measurement errors is biased. After the calibration of the estimators of the regression coefficient functions, we construct an empirical-process-based test statistic by the attenuation of corrected residuals. The asymptotic properties of the test statistic under the null hypothesis, global and various local alternatives are established. Simulation studies and real data analyses reveal that the proposed test performs satisfactorily.

Skull stripping or brain extraction on magnetic resonance imaging is a crucial step for structure analyses. In spite of good performances of conventional methods on adult brains, the skull stripping for T1-weighted imaging (T1WI) images on the neonatal brain remains a challenge because of the low image contrast. Therefore, this paper proposes a multi-view pyramid skull stripping network (PSSNet) for neonatal T1WI. To achieve superior skull stripping performance, the conventional pyramid scene parsing network was modified through (1) adding the spatial information of raw feature maps by squeezing the channel information during the feature extraction; (2) increasing the receptive field and adding boundary repair block instead of direct up-sampling; (3) obtaining the final mask through a fusion module on multi-view 2D slices. The 3D skull stripping problem was decomposed into multi-view 2D segmentation tasks to improve the efficiency. We enrolled T1WI images of 70 neonates from the local hospital and 7 infants from the publicly available dataset NeuroBrainS12 (MICCAI 2012). Images of 51 and 26 subjects were used for model training and validation. We compared the proposed method with 7 commonly used methods by using the Dice ratio, sensitivity, specificity, and efficiency. The proposed multi-view PSSNet with the highest Dice ratio (95.44–97.33%) was superior to other methods. Meanwhile, the sensitivity (93.19–97.02%), specificity (97.52–99.68%), and efficiency (8.59–9.30 s per subject) of the proposed method were comparable with the state-of-the-art method. In conclusion, the proposed skull stripping network was robust on neonatal T1WI datasets and feasible in clinical applications.

Electrocatalytic nitrate reduction reaction (NO

Urolithiasis is a common urological disease with a high morbidity and recurrence rate, of which calcium oxalate (CaOx) is the most common type of stone that underlies the disease. However, the potential metabolic mechanisms of CaOx urolithiasis remain unclear. The present study aimed to seek potential biomarkers and metabolic mechanisms of CaOx urolithiasis in adults. Urine samples were collected from 36 healthy individuals and 36 patients diagnosed with bilateral upper-urinary-tract stones. All of the stones were composed of CaOx. Ultra-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) was used to perform a metabolic fingerprinting analysis. Principal component analysis (PCA) and orthogonal partial least-squares determinant analysis (OPLS-DA) were carried out to analyze the multivariate data. There were 18 differential metabolites identified, which mainly involved caffeine, phenylalanine, galactose, and tyrosine metabolism. The results revealed potential urinary biomarkers, via metabolic fingerprinting of adults with CaOx urolithiasis, which may help to improve future metabolic evaluation of urolithiasis. The elucidated metabolic pathways may have potential applications as novel treatment targets of CaOx urolithiasis. Additionally, our study suggests that the UPLC-Q-TOF/MS platform may offer new insights into the pathobiology of urolithiasis.

Background and Purpose Periventricular pseudocysts (PVPCs) are cystic cavities originating from the germinal matrix. The effects of PVPCs on the development of white matter (WM) in neonates remain unclear. This study aimed to characterise WM microstructural variations in neonates with PVPCs with and without additional abnormities on MRI. Materials and methods Neonates with PVPCs and controls with no MRI abnormalities were retrospectively enrolled. Test subjects were divided into groups 1 (isolated PVPCs) and 2 (PVPCs with additional MRI abnormalities). The PVPC MRI features collected included lateralisation, locularity, anatomic location, and the maximum anteroposterior diameter. Diffusion tensor imaging (DTI)-derived fractional anisotropy (FA), radial diffusivity (RD), and axial diffusivity (AD) were compared between the PVPC and control groups using tract-based spatial statistics. Results Thirty-eight neonates with PVPCs and 60 controls were enrolled. Groups 1 and 2 contained 15 and 23 subjects, respectively. The additional MRI findings in group 2 included intracranial haemorrhage, punctate WM lesions, hypoxic-ischaemic encephalopathy, and acute cerebral infarction. No significant differences were found in PVPC MRI features between the 2 test groups. Compared to controls, no significant changes in DTI metrics were observed in group 1 neonates; whereas extensive WM regions with decreased FA, increased RD, and unchanged/increased AD were found in group 2. Conclusions Isolated PVPCs are not independently correlated with WM microstructural variations in neonates. This result provides further evidence for supporting the benign outcome of fetuses with isolated PVPCs.

SrTiO3 is a promising candidate photocatalyst for overall water splitting. Loading suitable cocatalysts, such as NiOx, the mixture of Ni and NiO, remarkably improve the photocatalytic activity. However, spatial locations and functions of components in NiOx/SrTiO3 are under debate. Here, using first-principles density functional theory (DFT) calculations, we investigate the initial growth of Nin (n = 1–4) and (NiO)n (n = 1, 2 and 4) clusters on stoichiometric (100) surfaces of SrTiO3, and explore interfacial and electronic structures of composite photocatalysts. It is found that Nin clusters are easier to undergo aggregation on SrO-termination than on TiO2-termination. The adsorption of Nin cluster on (100) surfaces elevates the Fermi level towards the conduction band, which may benefit the occurrence of hydrogen evolution reaction. The structural similarity between (NiO)n cluster and surface has an essential effect on the most stable adsorption configuration. For (NiO)n/SrTiO3 systems, the occupied states of (NiO)n cluster well overlap with those of (100) surfaces in the valence band maximum, which is in favor of the separation of photogenerated electrons and holes to SrTiO3 support and (NiO)n cluster, respectively. The detailed DFT analysis provides important insights into the growth of NiOx on surfaces of SrTiO3 and presents an explanation on the different models of NiOx/SrTiO3 photocatalyst proposed by experimental groups. Our calculations build a basis for further investigations on the mechanism of photocatalytic water-splitting reaction in NiOx/SrTiO3 composite system.

Background Dietary fiber is the undigested carbohydrate that escapes small intestinal digestion and absorption, and then reaches the large intestine for partial or complete fermentation by the colonic microbiota. Fermentation of dietary fiber into short-chain fatty acids (i.e., acetic, propionic, and butyric particularly) in the colon has been reported to bring about positive changes in microbiota composition and reduce the risk of colon-related diseases as well as some metabolic syndromes, such as obesity, diabetes, chronic kidney disease, and systemic inflammation. Scope and approach There is a growing interest in the fate of different dietary fibers in the gastrointestinal tract regarding their rate and extent (location) of fermentation and microbiota changes, particularly from data obtained with static and dynamic in vitro models. These models provide information on the fermentation performance and microbiota modulation by dietary fibers with diverse structures and enable the formulation of functional foods with health benefits. Key findings and conclusions This review summarizes the fermentation performance of various dietary fibers using in vitro models. Both the physical and chemical structures of dietary fibers are critical factors that determine fermentation rate, short-chain fatty acid profiles and growth of different bacterial groups. Considering the potential relationship between fermentation performance and health, three principles for designing fermentable dietary fiber are proposed: slow fermentation in the colon; high butyrate and/or propionate production; and selective bacterial growth, promoting the beneficial bacteria that improve the intestinal barrier function.

Epoxide hydrolases (EHs) are attractive enzymes for producing enantiopure epoxides and diols, but do not display enough stability when lysates or Escherichia coli whole cells are used as biocatalysts. In this work, an organic-solvent tolerant strain Rhodococcus ruber THdAdN was utilized to overexpress an epoxide hydrolase from Agrobacterium radiobacter (ArEH), using E. coli BL21(DE3) as a control. The proportion of ArEH in all soluble proteins of R. ruber THdAdN(ArEH) reached 30.3%, which was comparable to that of E. coli BL21(DE3)(ArEH). Due to a higher cell density in flask cultivation, the maximum ArEH activity of R. ruber THdAdN(ArEH) toward epichlorohydrin (ECH) reached 5.4 U/mL, approximately 5-fold higher than that of E. coli BL21(DE3)(ArEH). More importantly, compared with E. coli BL21(DE3)(ArEH), ArEH in R. ruber THdAdN(ArEH) showed a 10-fold enhanced thermostability, better tolerance against alkali pH, and reduced substrate and product inhibition, which significantly improved its performance in the resolution of high concentration ECH. By substrate feeding, 98.5% ee (R)-ECH was obtained with a 35.5% yield from 512 mM racemic ECH hydrolyzed by R. ruber THdAdN(ArEH). Compared with using free enzyme as biocatalysts, utilization of the R. ruber cells harboring ArEH improved the final (R)-ECH concentration by 46%.

Soil carbon (C), nitrogen (N), and phosphorus (P) are some of the most important indicators of soil quality, especially in fragile ecological environments with shallow soils. However, the differences in their variations and influencing factors related to scale in karst areas remain unclear. Therefore, variations in surface soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) distributions and their determinant factors were quantitatively analyzed at different scales (i.e., region, sub-region, and catchment) in a typical karst area, southwest China. Overall, both soil nutrient variations and the determinant factors involved varied with scale. The coefficients of variation for SOC, TN, and TP increased significantly from catchment to sub-region scales but changed only slightly between sub-region and region scales. At region and sub-region scales, lithology only affected TP significantly, while land use affected all soil nutrients significantly. However, the explanations for TP variation by lithology and for SOC, TN, and TP variations by land use increased by 12.2, 7.0, 11.0, and 12.8% at sub-region scale over the values observed at region scale, respectively. When lithology and land use were controlled, soil depth was observed playing an important role in soil nutrients at the three studied scales. At region and sub-region scales, other factors related to soil texture (clay, silt, or sand content), topography (elevation or TWI), and climate (MAT or MAP) were selected as significant variables and accounted for a larger proportion of nutrient variation. However, at catchment scale, bare rock rate and micro-topography (e.g., slope) explained soil nutrient variation to a larger proportion. Therefore, elucidation of the role of factors influencing soil nutrients at different scales can provide a guide for soil quality assessment in karst areas.

Poly(vinyl alcohol) (PVA)-xanthan gum (XG) hydrogel, which possesses good reusable absorption properties, has been prepared by the freezing–thawing method. Hydrogels prepared with different ratios compositions are characterized using Fourier transform infrared spectroscopy (FTIR) and Scanning electron microscope (SEM), and examined in terms of their swelling behavior, mechanical, rheological and adsorption properties. The results show that a shift in the major signals of FTIR for OH absorption, and with varied intensities in the FTIR spectra andmore and more wrinkles observed in SEM indicated cross-linked interaction by the polymers. All the features of the PVA-XG hydrogel are closely related to its rheological properties. The presence of XG visibly improves the swelling ratio of PVA-XG and reduces the compression properties of PVA-XG due to the formation of hydrogen bonds between the PVA and XG. PVA-XG-4 had the best adsorption of methylene blue (MB) dye, such enhancement in adsorption can be attributed to strong electrostatic attraction between XG and MB. The adsorption conformed to the second-order kinetic model and the adsorption process conformed to the Langmuir isotherm model. In addition, PVA-XG-4 exhibits a promising cycling absorption performance. The 1st and 5th cycle of dye removal for PVA-XG-4 reached to 92 and 80%, respectively. Provides basis for application in water treatment.

Bovine viral diarrhea virus (BVDV) infection causes significantly economic losses to cattle industry worldwide, also including China. The epidemiological prevalence of infection associated with BVDV in dairy cattle has not been systematically assessed in China. Therefore, we undertook this study to evaluate prevalent of BVDV infection. We conducted a systematic review and meta-analysis of data from papers on the BVDV incidence and prevalence in dairy cattle in China by searching China Science and Technology Journal Database, China National Knowledge Infrastructure (CNKI), Wan Fang Database and PubMed for publication from March 2003 to March 2018. The 41 studies reporting the prevalence of BVDV in cattle in China were selected upon our inclusion criterion. The pooled BVDV prevalence in dairy cattle in China was estimated to 53.0% (95% CI 40.2–65.7) based on the data obtained from the 27,530 cows tested using serological or virological assay in the qualified papers published during the periods (χ² = 51,861.0, I2 = 99.9%). The highest BVDV positive rate in dairy flocks reached 90.0% in Fujian province of China, followed by Shaanxi (88.9%) and Shandong (83.3%). The prevalence in the six administrative districts of China was validated to be highly variable (25.7%–72.2%) and reached 72.2% in dairy cattle flocks of Northern China. Besides, the BVDV-RNA positive rate was estimated 27.1% (95% CI 17.3–37.0) based on 6 studies, comparatively, the pooled BVDV seroprevalence based on 35 studies was about 57.0% (95% CI 44.4–69.5) in China. This systematic review and meta-analysis firstly established an estimated prevalence of BVDV in dairy herds in China, indicating that the BVDV infection is escalating, though there is a bias in the number of studies between 2003–2009 and 2010–2018 timescales. This study may help understand the status of BVDV infection in dairy herds in China. Further extensive and comprehensive investigation is recommended, and effective intervention measures for preventing and controlling BVDV spread in dairy herds should be deployed, especially herds that have been exposed to BVDV.

Two pairs of new flavans, moracinflavan A and B (1a/1b and 2a/2b), together with another five new flavan derivatives moracinflavan C–G (3–7), and three known flavans (8–10) were isolated from the leaves of Morus alba. Their structures were elucidated by detailed analyses based on spectroscopic data. Separation of the stereoisomeric mixtures of 1a and 1b, 2a and 2b was achieved using chiral HPLC, and the absolute configurations of the respective stereoisomers were determined based on comparison of experimental and calculated electronic circular dichroism (ECD) spectra. Using an ARE-dependent luciferase reporter assay, we identified that these flavans were capable of increasing ARE-luciferase activities. This indicated that these flavans are potential Nrf2 activators.