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[Display omitted] [ABSTRACT FROM AUTHOR]

Continuously recording the dynamic changes of circulating tumor cells (CTCs) is crucial for tumor metastasis. This paper creates a continuous magnetic separation microfluidic chip that enables rapid and continuous in vivo cell detection. The chip shows its potential to study tumor cell circulation in the blood, offering a new platform for studying the cellular mechanism of tumor metastasis. [ABSTRACT FROM AUTHOR]

Biochar amendment is one of the most promising agricultural approaches to tackle climate change by enhancing soil carbon (C) sequestration. Microbial‐mediated decomposition processes are fundamental for the fate and persistence of sequestered C in soil, but the underlying mechanisms are uncertain. Here, we synthesise 923 observations regarding the effects of biochar addition (over periods ranging from several weeks to several years) on soil C‐degrading enzyme activities from 130 articles across five continents worldwide. Our results showed that biochar addition increased soil ligninase activity targeting complex phenolic macromolecules by 7.1%, but suppressed cellulase activity degrading simpler polysaccharides by 8.3%. These shifts in enzyme activities explained the most variation of changes in soil C sequestration across a wide range of climatic, edaphic and experimental conditions, with biochar‐induced shift in ligninase:cellulase ratio correlating negatively with soil C sequestration. Specifically, short‐term (<1 year) biochar addition significantly reduced cellulase activity by 4.6% and enhanced soil organic C sequestration by 87.5%, whereas no significant responses were observed for ligninase activity and ligninase:cellulase ratio. However, long‐term (≥1 year) biochar addition significantly enhanced ligninase activity by 5.2% and ligninase:cellulase ratio by 36.1%, leading to a smaller increase in soil organic C sequestration (25.1%). These results suggest that shifts in enzyme activities increased ligninase:cellulase ratio with time after biochar addition, limiting long‐term soil C sequestration with biochar addition. Our work provides novel evidence to explain the diminished soil C sequestration with long‐term biochar addition and suggests that earlier studies may have overestimated soil C sequestration with biochar addition by failing to consider the physiological acclimation of soil microorganisms over time. [ABSTRACT FROM AUTHOR]

The development of different efficient flame retardants (FRs) to improve the fire safety of polymers has been a hot research topic. As the concept of green sustainability has gradually been raised to the attention of the whole world, it has even dominated the research direction of all walks of life. Therefore, there is an urgent calling to explore the green and simple preparation methods of FRs. The development of supramolecular chemistry in the field of flame retardancy is expanding gradually. It is worth noting that the synthesis of supramolecular flame retardants (SFRs) based on non-covalent bonds is in line with the current concepts of environmental protection and multi-functionality. This paper introduces the types of SFRs with different dimensions. SFRs were applied to typical polymers to improve their flame retardancy. The influence on mechanical properties and other material properties under the premise of flame retardancy was also summarized. [ABSTRACT FROM AUTHOR]

Breaking the trade-off between activity and selectivity has been a long-standing challenge in the field of catalysis. We demonstrate the importance of disentangling the target reaction from the secondary reactions for the case of direct syngas conversion to light olefins by incorporating germanium-substituted AlPO-18 within the framework of the metal oxide-zeolite (OXZEO) catalyst concept. The attenuated strength of the catalytically active Brønsted acid sites allows enhancing the targeted carbon-carbon coupling of ketene intermediates to form olefins by increasing the active site density while inhibiting secondary reactions that consume the olefins. Thus, a light-olefins selectivity of 83% among hydrocarbons and carbon monoxide conversion of 85% were obtained simultaneously, leading to an unprecedented light-olefins yield of 48% versus current reported light-olefins yields of ≤27%. [ABSTRACT FROM AUTHOR]

This paper summarizes the research status of natural starch graft modification methods, graft monomer selection, product preparation and purification, analyzes and summarizes different initiation methods and different types of graft products, looks forward to the development prospect of natural starch graft modified flocculant, and points out that while exploring better graft effect and flocculation effect, pay attention to the research on the universality of this kind of flocculant and the reduction of production cost. [ABSTRACT FROM AUTHOR]

Simple Summary: In this article, we studied the interactions between the invasive thrips pest Frankliniella occidentalis (WFT) and a native thrips Frankliniella intonsa (IFT) in China, where they co-exist on crop plants and WFT seems to outcompete IFT. In laboratory bioassays we focused on the reproductive mode of the thrips (sexual or parthenogenic), and the presence of a sugar source (honey or flowers), both variables that change over time during pest colonisation of a crop. Our results suggest that in the early stages of F. occidentalis invasion, the provision of honey (flowering) promotes this pest's population development. This research will inform effective strategies for the management of F. occidentalis invasion and help reduce subsequent crop damages. Background: Flower thrips (Frankliniella intonsa, IFT) and west flower thrips (Frankliniella occidentalis, WFT) are often found together on the host plant in China. WFT is an important invasive species that seems to outcompete the native IFT. In order to clarify the interspecific competitions between the two thrips, this study measured the population development of IFT and WFT under sexual and parthenogenetic reproductive modes on two hosts (fresh lentil bean pods with/without honey and pepper plants at seedling/flowering stages) in the laboratory. Results: When reared on fresh lentil bean pods (with/without honey), WFT population size was lower in mixed species populations compared to single species populations but the presence of WFT had nor negative effect on IFT population size. These results were dependent of the reproductive mode. When honey was supplied, the ratio of female-to-male in the progeny of WFT produced under sexual reproductive mode increased significantly in the presence of IFT. On pepper seedlings, mixed populations were more favorable to the population development of IFT at the seedling stage, but more favorable to WFT at the flowering stage. Conclusions: In the early stage of WFT invasion and colonization, the emergence of flowering and honey (nectar) sources may have a positive effect on the population development of WFT. [ABSTRACT FROM AUTHOR]

Phenolic compounds and their derivatives play a major role in the intensity and characteristics of grape (Vitis vinifera) astringency. The present study investigated the relationship between phenolic composition and astringency of six commercial table grape varieties (two of each white‐, red‐, and black‐skinned). Qualitative and quantitative liquid chromatography–mass spectrometry analysis was used to identify the variety‐specific phenolic profiles in the skins and total astringency intensity was assessed and described by a trained sensory panel. Thirty phenolic compounds were identified among the six varieties. Principal component analysis of the phenolic profiles revealed that the intensity of astringency of grape skin was positively correlated with catechin, epicatechin, epicatechin‐3‐O‐gallate, and proanthocyanidin dimers B1, B2, and B3. A further orthogonal partial least‐squares discrimination analysis of these compounds showed that catechin was the substance most strongly and positively correlated (R = 0.904) with grape skin astringency. Practical Application: This study provided a better understanding of the relationships between phenolic composition and table grape astringency and highlighted a potential metabolic marker that could be used as a predictor for the complex astringency sensory attributes of table grape berries. [ABSTRACT FROM AUTHOR]

Background: Itaconic acid, an unsaturated C5 dicarbonic acid, has significant market demand and prospects. It has numerous biological functions, such as anti-cancer, anti-inflammatory, and anti-oxidative in medicine, and is an essential renewable platform chemical in industry. However, the development of industrial itaconic acid production by Aspergillus terreus, the current standard production strain, is hampered by the unavoidable drawbacks of that species. Developing a highly efficient cell factory is essential for the sustainable and green production of itaconic acid. Results: This study employed combinatorial engineering strategies to construct Escherichia coli cells to produce itaconic acid efficiently. Two essential genes (cis-aconitate decarboxylase (CAD) encoding gene cadA and aconitase (ACO) encoding gene acn) employed various genetic constructs and plasmid combinations to create 12 recombination E. coli strains to be screened. Among them, E. coli BL-CAC exhibited the highest titer with citrate as substrate, and the induction and reaction conditions were further systematically optimized. Subsequently, employing enzyme evolution to optimize rate-limiting enzyme CAD and synthesizing protein scaffolds to co-localize ACO and CAD were used to improve itaconic acid biosynthesis efficiency. Under the optimized reaction conditions combined with the feeding control strategy, itaconic acid titer reached 398.07 mM (51.79 g/L) of engineered E. coli BL-CAR470E-DS/A-CS cells as a catalyst with the highest specific production of 9.42 g/g(DCW) among heterologous hosts at 48 h. Conclusions: The excellent catalytic performance per unit biomass shows the potential for high-efficiency production of itaconic acid and effective reduction of catalytic cell consumption. This study indicates that it is necessary to continuously explore engineering strategies to develop high-performance cell factories to break through the existing bottleneck and achieve the economical commercial production of itaconic acid. [ABSTRACT FROM AUTHOR]

Context: Morinda officinalis F.C. How. (MO) (Rubiaceae) can strengthen bone function. Objective: To examine the functional mechanism and effect of MO polysaccharides (MOPs) in rats with glucocorticoid-induced osteoporosis (GIOP). Materials and methods: Rats with GIOP were treated with 5, 15 or 45 mL/kg of MOP [n=15 for each dose, intraperitoneal (i.p.) injection every other day for 8 weeks]. The body weight of rats and histomorphology of bone tissues were examined. Bone marrow mesenchymal stem cells (BMSCs)-derived exosomes (Exo) were collected and identified. Bone marrow-derived macrophages (BMMs) were induced to differentiate into osteoclasts and treated with BMSC-Exo for in vitro studies. Results: MOP reduced the body weight (5, 15, or 45 mg/kg MOP vs. phosphate-buffered saline: 8%, 15% and 25%, p<0.01), elevated the bone volume to tissue volume (BV/TV), mean trabecular thickness (Tb.Th), mean trabecular number (Tb.N) and mean connectivity density (Conn.D) (40-86%, p<0.01), decreased the mean trabecular separation/spacing (Tb.Sp) (22-37%, p<0.01), increased the cortical bone continuity (35-90%, p<0.01) and elevated RUNX family transcription factor 2 and RANK levels (5-12%, p<0.01), but suppressed matrix metallopeptidase 9 and cathepsin K levels (9-20%, p<0.01) in femur tissues. BMSC-Exo from MOP-treated rats (MOP-Exo) suppressed osteoclastic differentiation and proliferation of BMMs. The downregulation of microRNA-101-3p (miR-101-3p) or the upregulation of prostaglandinendoperoxide synthase 2 (PTGS2) blocked the functions of MOP-Exo. Discussion and conclusions: MOP inhibits osteoclastic differentiation and could potentially be used for osteoporosis management. This suppression may be enhanced by the upregulation of miR-101-3p or the inhibition of PTGS2. [ABSTRACT FROM AUTHOR]

A modified power spectrum of biological tissues involving upper length-scale and bottom length-scale was introduced. In addition, the analytical expression of Hermite–Gaussian rectangular vortex beam with the parameter ( n = 2) in free space was derived. By this modified power spectrum, we established the normalized probability model of orbital angular momentum (OAM) states for Hermite–Gaussian rectangular vortex beams propagation in biological tissues. The results revealed that Hermite–Gaussian rectangular vortex beam exhibits a better anti-interference performance than Laguerre–Gaussian beam under the same conditions. The Hermite–Gaussian rectangular vortex beam propagates through a biological tissue with large bottom length-scale, small upper length-scale, small characteristic length of heterogeneity, low the fractal dimensions, and weak fluctuation strength, which produces a large normalized probability of signal OAM states. These results are fundamental to improving light propagation in tissue and provide a quantitative guidance for medical imaging and diagnosis. [ABSTRACT FROM AUTHOR]

Warming is known to reduce soil carbon (C) stocks by promoting microbial respiration, which is associated with the decomposition of microbial residue carbon (MRC). However, the relative contribution of MRC to soil organic carbon (SOC) across temperature gradients is poorly understood. Here, we investigated the contribution of MRC to SOC along two independent elevation gradients of our model system (i.e., the Tibetan Plateau and Shennongjia Mountain in China). Our results showed that local temperature increases were negatively correlated with MRC and SOC. Further analyses revealed that rising temperature reduced SOC via decreasing MRC, which helps to explain future reductions in SOC under climate warming. Our findings demonstrate that climate warming has the potential to reduce C sequestration by increasing the decomposition of MRC, exacerbating the positive feedback between rising temperature and CO2 efflux. Our study also considered the influence of multiple environmental factors such as soil pH and moisture, which were more important in controlling SOC than microbial traits such as microbial life‐style strategies and metabolic efficiency. Together, our work suggests an important mechanism underlying long‐term soil C sequestration, which has important implications for the microbial‐mediated C process in the face of global climate change. [ABSTRACT FROM AUTHOR]

[Display omitted] • Different taste and aroma characteristics were presented in 4 white tea and their processing samples. • The maturity of fresh tea leaves was the primary factor that promoted the formation of milky flavor. • The processing method was the key to inducing milky aroma under mature fresh tea leaves conditions. Targeted metabolomics combined with chemometrics were applied to investigate the flavor profiles of 4 white tea samples, which were produced from different maturity fresh tea leaves with different withering methods. Mature leaves that underwent novel withering process at higher temperature (28-30℃) and humidity (75 ± 3 %) (MN) were characterized by intense milky flavor. The content of free amino acids, catechins, and soluble sugars in MN were significantly lower than that in the other 3 tea samples, resulting in a sweet and mellow taste with low bitterness. Meanwhile, MN possessed the highest intensity of milky aroma, which could be mainly attributed to the existence of dihydro-5-pentyl-2(3H)-furanone and 2-pentyl-furan as the key volatile substances with coconut and creamy fragrance. These findings provide insight into the substance foundations of milky flavor, and identified leaf maturity and processing method as the determining factors of the milk-flavored white tea (MFWT). [ABSTRACT FROM AUTHOR]

The copper-modified tubular carbon nitride (CTCN) with higher specific surface area and pore volume was prepared by a simple in-situ hydrolysis and self-assembly. Increased ∼4.7-fold and ∼2.3-fold degradation rate for a representative refractory water pollutant (Ibuprofen, IBP) were achieved with low-energy light source (LED, 420 ± 10 nm), as compared to graphitic carbon nitride (GCN) and tubular carbon nitride (TCN), respectively. The high efficiency of IBP removal was supported by narrow band gap (2.15 eV), high photocurrent intensity (1.10 μA/cm2) and the high surface -OH group (14.75 μg/cm3) of CTCN. According to analysis of the various reactive species in the degradation, the superoxide radical (•O 2 −) played a dominant role, followed by •OH and h+, responsible for IBP degradation. Furthermore, Fukui functions were employed to predict the active sites of IBP, and combined with the HPLC-MS/MS results, possible mechanisms and pathways for photocatalytic degradation were indicated. This study will lay an important scientific foundation and a possible new approach for the treatment of emerging aromatic organic pollutants in visible-light-driven heterogeneous catalytic oxidation environment. [Display omitted] • Cu modified tubular carbon nitride (CTCN) was prepared by situ hydrolysis and self-assembly method. • The first study on photocatalysis without co-catalysts for the degradation of Ibuprofen (IBP) by CTCN. • High IBP removal was ascribed to the high reactivity of CTCN and the active site activation of Cu. • Among reactive species (.•O 2 −, •OH and h+) participated in photocatalytic oxidation, •O 2 − played the most significant role. [ABSTRACT FROM AUTHOR]

Phospholipase B (PLB) harbors three distinct activities with broad substrate specificities and application fields. Its hydrolyzing of sn-1 and sn-2 acyl ester bonds enables it to catalyze the production of L-alpha-glycerylphosphorylcholine (L-α-GPC) from phosphatidylcholine (PC) without speed-limiting acyl migration. This work was intended to obtain high-level active PLB and apply it to establish an efficient system for L-α-GPC synthesis. PLB from Pseudomonas fluorescens was co-expressed with five different molecular chaperones, including trigger factor (Tf), GroEL-GroES (GroELS), DnaK-DnaJ-GrpE (DnaKJE), GroELS and DnaKJE, or GroELS and Tf or fused with maltose binding protein (MBP) in Escherichia coli BL21(DE3) to improve PLB expression. PLB with DnaKJE-assisted expression exhibited the highest catalytic activity. Further optimization of the expression conditions identified an optimal induction OD600 of 0.8, IPTG concentration of 0.3 mmol/L, induction time of 9 h, and temperature of 25 °C. The PLB activity reached a maximum of 524.64 ± 3.28 U/mg under optimal conditions. Subsequently, to establish an efficient PLB-catalyzed system for L-α-GPC synthesis, a series of organic-aqueous mixed systems and surfactant-supplemented aqueous systems were designed and constructed. Furthermore, the factors of temperature, reaction pH, metal ions, and substrate concentration were further systematically identified. Finally, a high yield of 90.50 ± 2.21% was obtained in a Span 60-supplemented aqueous system at 40 °C and pH 6.0 with 0.1 mmol/L of Mg2+. The proposed cost-effective PLB production and an environmentally friendly PLB-catalyzed system offer a candidate strategy for the industrial production of L-α-GPC. [ABSTRACT FROM AUTHOR]

Objective: Endogenous hormones regulate numerous physiological processes in humans. Some of them are routinely measured in blood, saliva and/or urine for the diagnosis of dis orders. The analysis of fluids may, however, require multiple samples collected at different time points to avoid the high variability in the concentration of some hormones. In contrast, hair analysis has been proposed as an interesting alternative to reveal average hormone levels over a longer period. In this work, we developed and validated an anal ytical method for analyzing 36 endogenous steroid and thyroid hormones and one pineal hormone in human hair using ult ra-performance liquid chromatography (UPLC)-tandem mass spectrometry (MS/MS). Methods: Sample preparation involved hair decontamination, pulverization, methanol extraction, and purification with C18-solid phase extraction. Extracts were then divided into two po rtions, respectively injected into an UPLC-MS/MS system, and analyzed using two different instrumental methods. The method was applied to a healthy female population aged 25-45 years. Results: The method was validated on supplemented hair samples for the 37 targeted hormones, and its application to the population under study allowed to detect 32 compounds in 2-100% of the samples. Complete reference intervals (2.5-97.5th percentiles) were established for estrone, 17ß-estradiol, androstenedione, dehydroepiandrosterone, progesterone, 17a-hydroxyprogesterone, cortisone, cortisol and 3,3',5-triiodo-L-thyronine. Hair cortisone, cortisol, tetrahydrocortisone and tetrahydrocortisol concentrations were highly correlated with each other, with Kendall's t correlation coefficients ranging from 0.52 to 0.68. Conclusion: Allowing the detection of 32 hormones from different chemical c lasses, the present method will allow to broaden hormonal profiling for better identifying endocrine diso rders. [ABSTRACT FROM AUTHOR]

Diabetes mellitus (DM) is a leading risk factor for age-related dementia, but the mechanisms involved are not well understood. We previously discovered that hyperglycemia induced impaired myogenic response (MR) and cerebral blood flow (CBF) autoregulation in 18-mo-old DM rats associated with blood-brain barrier (BBB) leakage, impaired neurovascular coupling, and cognitive impairment. In the present study, we examined whether reducing plasma glucose with a sodium-glucose cotransporter-2 inhibitor (SGLT2i) luseogliflozin can ameliorate cerebral vascular and cognitive function in diabetic rats. Plasma glucose and HbA1c levels of 18-mo-old DM rats were reduced, and blood pressure was not altered after treatment with luseogliflozin. SGLT2i treatment restored the impaired MR of middle cerebral arteries (MCAs) and parenchymal arterioles and surface and deep cortical CBF autoregulation in DM rats. Luseogliflozin treatment also rescued neurovascular uncoupling, reduced BBB leakage and cognitive deficits in DM rats. However, SGLT2i did not have direct constrictive effects on vascular smooth muscle cells and MCAs isolated from normal rats, although it decreased reactive oxygen species production in cerebral vessels of DM rats. These results provide evidence that normalization of hyperglycemia with an SGLT2i can reverse cerebrovascular dysfunction and cognitive impairments in rats with long-standing hyperglycemia, possibly by ameliorating oxidative stress-caused vascular damage. [ABSTRACT FROM AUTHOR]

Recent studies have shown a trend towards using materials containing multiple proteins by high-moisture extrusion in plant-based meat analogs (PBMA). However, research on the selection of plant proteins and multiple protein structure changes during extrusion is limited. In this study, pea protein (PP), soy protein isolate (SPI), chickpea protein (CP) and wheat gluten (WG) were blended to prepare four mixtures, PP, PP-WG, PP-SPI-WG, and PP-CP-WG, were investigated for their effects on texture properties and protein structure of the extrudates, and changes in protein structure of PP-CP-WG mixture during the extrusion process were studied. The PP-CP-WG extrudates displayed the highest levels of hardness, chewiness, and fibrous degree of extrudates (25.80 ± 0.20, 4.65 ± 0.14, and 1.25 ± 0.04, respectively, P < 0.05). High-moisture extrusion led to a significant increase in disulfide bonds content and a significant decrease in surface hydrophobicity for four mixtures (with increases ranging from 35 to 80 % and decreases ranging from 9 to 39 %). During extrusion, the content of disulfide bonds increased, reaching a maximum value of 3.36 ± 0.02 μmol/g in the die, surface hydrophobicity decreased, the β-sheet content rose from 50.25 ± 0.23 % to 56.74 ± 0.71 %, and the fluorescence intensity decreased. This study would be useful for the development of PBMA containing a variety of proteins. • Extrusion of materials containing multiple proteins were studied. • PP-CP-WG extrudates displayed the highest levels of fibrous degree. • Thermal stability of proteins was significantly changed after extrusion. • Extrusion decreased the fluorescence intensity of raw proteins. • Disulfide bond content increased and then decreased during extrusion. [ABSTRACT FROM AUTHOR]

Background: Appropriate allocation of nursing staff is key to ensuring efficient nursing in hospitals, and is significantly correlated with patient safety, nursing quality, and nurse job satisfaction. However, there are few studies on nursing workforce allocation in the isolation wards of COVID-19 designated hospitals globally. This study aims to better understand the nursing workforce allocation in the isolation wards of COVID-19 designated hospitals in China, and provide a theoretical basis for efficiently deploying first-line nurses in China and across the world in the future. Methods: An online survey was conducted among the head nurses (n = 229) and nurses (n = 1378) in the isolation wards of 117 hospitals (selected by stratified sampling), using a self-reported human resource allocation questionnaire. Results: The average bed-to-nurse ratios of different isolation wards were different (Z = 36.742, P = 0.000). The bed-to-nurse ratios of the ICU, suspected COVID-19 cases ward, and confirmed COVID-19 cases ward, were 1:1.88, 1:0.56, and 1:0.45, respectively. The nurse work hours per shift in different isolation wards were also different (Z = 8.468, P = 0.014), with the specific values of the ICU, suspected COVID-19 cases ward, and confirmed COVID-19 cases ward, being 5, 6, and 6 h, respectively. A correlation analysis showed that the average work hours per shift was proportional to the overtime work of nurses (rs = 0.146), the proportion of nurse practitioners was proportional to the overall utilization rate of nursing human resources in the wards (rs = 0.136), and the proportion of nurses with college degrees was proportional to teamwork (rs = 0.142). The proportion of nurses above grade 10 was inversely proportional to teamwork and psychological problems (rs = 0.135, rs = 0.203). The results of multiple stepwise regression analyses showed that the work hours of nurses per shift was the main factor affecting nurse satisfaction and that the proportion of nurses and the work hours of nurses per shift were both independent factors affecting the length of stay (LOS) of patients. Conclusion: Hospitals in China have made good nursing workforce allocations during the COVID-19 pandemic, but there are certain shortcomings. Therefore, scientific and efficient nursing workforce allocation practice plans should be established to improve the ability of hospitals to deal with public health emergencies and are urgent problems that need to be addressed soon. [ABSTRACT FROM AUTHOR]

Background: Appropriate allocation of nursing staff is key to ensuring efficient nursing in hospitals, and is significantly correlated with patient safety, nursing quality, and nurse job satisfaction. However, there are few studies on nursing workforce allocation in the isolation wards of COVID-19 designated hospitals globally. This study aims to better understand the nursing workforce allocation in the isolation wards of COVID-19 designated hospitals in China, and provide a theoretical basis for efficiently deploying first-line nurses in China and across the world in the future. Methods: An online survey was conducted among the head nurses (n = 229) and nurses (n = 1378) in the isolation wards of 117 hospitals (selected by stratified sampling), using a self-reported human resource allocation questionnaire. Results: The average bed-to-nurse ratios of different isolation wards were different (Z = 36.742, P = 0.000). The bed-to-nurse ratios of the ICU, suspected COVID-19 cases ward, and confirmed COVID-19 cases ward, were 1:1.88, 1:0.56, and 1:0.45, respectively. The nurse work hours per shift in different isolation wards were also different (Z = 8.468, P = 0.014), with the specific values of the ICU, suspected COVID-19 cases ward, and confirmed COVID-19 cases ward, being 5, 6, and 6 h, respectively. A correlation analysis showed that the average work hours per shift was proportional to the overtime work of nurses (rs = 0.146), the proportion of nurse practitioners was proportional to the overall utilization rate of nursing human resources in the wards (rs = 0.136), and the proportion of nurses with college degrees was proportional to teamwork (rs = 0.142). The proportion of nurses above grade 10 was inversely proportional to teamwork and psychological problems (rs = 0.135, rs = 0.203). The results of multiple stepwise regression analyses showed that the work hours of nurses per shift was the main factor affecting nurse satisfaction and that the proportion of nurses and the work hours of nurses per shift were both independent factors affecting the length of stay (LOS) of patients. Conclusion: Hospitals in China have made good nursing workforce allocations during the COVID-19 pandemic, but there are certain shortcomings. Therefore, scientific and efficient nursing workforce allocation practice plans should be established to improve the ability of hospitals to deal with public health emergencies and are urgent problems that need to be addressed soon. [ABSTRACT FROM AUTHOR]

BACKGROUND: Neoadjuvant chemotherapy (NAC) is an important treatment for locally advanced breast cancer (LABC). However, there are no effective biomarkers to predict the efficacy. Therefore, there is an urgent need for new biomarkers to predict the response of LABC to NAC. LncRNA BCAR4 has been detected in a variety of malignant tumor tissues and used as a new biomarker for diagnosis and prognosis. However, LncRNA BCAR4 predicts the response of LABC to NAC is unclear. OBJECTIVE: Explore the predictive effect of LncRNA BCAR4 on the efficacy of NAC for LABC in three different evaluation systems. METHODS: First, the TCGA database was used to analyze the expression of LncRNA BCAR4 in 33 kinds of malignant tumors, and further explore its expression in breast cancer and its impact on the survival and prognosis of breast cancer. Furthermore, quantitative methods were used to measure the expression level of LncRNA BCAR4 in cancer tissues of 48 LABC patients, and the correlation between LncRNA BCAR4 and clinicopathological status and response to NAC under the evaluation system of 3, RECIST1.1, Miller-Payne (MP) score and whether it reaches pCR,was analyzed. RESULTS: TCGA data analysis found that LncRNA is highly expressed in a variety of malignant tumor tissues, including breast cancer. And relatively low expression, the shorter the overall survival time of high expression patients. The high expression of LncRNA BCAR4 is related to the size of the tumor, and there are differences in expression between stage I and other stages, but there is no obvious correlation with the positive lymph node and hormone receptor status. Among the three evaluation systems, only in the RECIST 1.1 evaluation system LncRNA BCAR4 has a predictive effect on NAC for LABC. The expression of LncRNA BCAR4 has no significant correlation with clinical stage, Ki-67% and hormone receptor status, and has no significant correlation with whether patients with locally advanced breast cancer obtain pCR during neoadjuvant chemotherapy. CONCLUSION: LncRNA BCAR4 is highly expressed in LABC tissues and may be an effective marker for predicting the efficacy of NAC for LABC. [ABSTRACT FROM AUTHOR]

BACKGROUND: Neoadjuvant chemotherapy (NAC) is an important treatment for locally advanced breast cancer (LABC). However, there are no effective biomarkers to predict the efficacy. Therefore, there is an urgent need for new biomarkers to predict the response of LABC to NAC. LncRNA BCAR4 has been detected in a variety of malignant tumor tissues and used as a new biomarker for diagnosis and prognosis. However, LncRNA BCAR4 predicts the response of LABC to NAC is unclear. OBJECTIVE: Explore the predictive effect of LncRNA BCAR4 on the efficacy of NAC for LABC in three different evaluation systems. METHODS: First, the TCGA database was used to analyze the expression of LncRNA BCAR4 in 33 kinds of malignant tumors, and further explore its expression in breast cancer and its impact on the survival and prognosis of breast cancer. Furthermore, quantitative methods were used to measure the expression level of LncRNA BCAR4 in cancer tissues of 48 LABC patients, and the correlation between LncRNA BCAR4 and clinicopathological status and response to NAC under the evaluation system of 3, RECIST1.1, Miller-Payne (MP) score and whether it reaches pCR,was analyzed. RESULTS: TCGA data analysis found that LncRNA is highly expressed in a variety of malignant tumor tissues, including breast cancer. And relatively low expression, the shorter the overall survival time of high expression patients. The high expression of LncRNA BCAR4 is related to the size of the tumor, and there are differences in expression between stage I and other stages, but there is no obvious correlation with the positive lymph node and hormone receptor status. Among the three evaluation systems, only in the RECIST 1.1 evaluation system LncRNA BCAR4 has a predictive effect on NAC for LABC. The expression of LncRNA BCAR4 has no significant correlation with clinical stage, Ki-67% and hormone receptor status, and has no significant correlation with whether patients with locally advanced breast cancer obtain pCR during neoadjuvant chemotherapy. CONCLUSION: LncRNA BCAR4 is highly expressed in LABC tissues and may be an effective marker for predicting the efficacy of NAC for LABC. [ABSTRACT FROM AUTHOR]

• In this work, we evaluated the potential mechanism of Nesfatin-1 in lipid metabolism and its role in lipid-related diseases, which is expected to provide a new therapeutic target for the prevention and treatment of obesity, metabolic syndrome and cardiovascular diseases. Nesfatin-1, an anorexic neuropeptide discovered in 2006, is widely distributed in the central nervous system and peripheral tissues. It has been shown to be involved in the regulation of food intake and lipid metabolism, inhibiting fat accumulation, accelerating lipid decomposition, and in general, inhibiting the development of lipid-related diseases, such as obesity and metabolic syndrome. Potential mechanisms of Nesfatin-1 action in lipid metabolism and lipid-related diseases will be discussed as well as its role as a biomarker in cardiovascular disease. This review expected to provide a new strategy for the diagnosis and prevention of clinically related diseases. [ABSTRACT FROM AUTHOR]

Vaccination is the most economic and effective measure to deal with infectious diseases and protect public health. Nowadays, due to the spread of COVID-19 and the ensuing pandemic, safe, effective vaccines are in urgent need. However, due to concerns about vaccine safety, there is still reluctance to vaccinate. In China, in response to the Changchun Changsheng Vaccine incident, the National People's Congress Standing Committee passed the Vaccine Administration Law in 2019, which marks China's first comprehensive piece of legislation on vaccine regulation. The law establishes a regulatory system covering the entire life cycle of vaccines, introduces the vaccine marketing authorization holder system, stipulates the legal responsibilities of all parties, and further clarifies the compensation system for any individuals who exhibit abnormal reactions to vaccination. In addition, it emphasizes the use of modern technology to build a national vaccine electronic platform for tracing. To balance vaccine efficacy and safety, it is necessary to further improve the vaccine risk management mechanism, promote cooperation between government and non-governmental actors, and avoid improper interventions in the vaccine market. [ABSTRACT FROM AUTHOR]

Background: SMARCAs, belonged to SWI/SNF2 subfamilies, are critical to cellular processes due to their modulation of chromatin remodeling processes. Although SMARCAs are implicated in the tumor progression of various cancer types, our understanding of how those members affect pancreatic carcinogenesis is quite limited and improving this requires bioinformatics analysis and biology approaches. Methods: To address this issue, we investigated the transcriptional and survival data of SMARCAs in patients with pancreatic cancer using ONCOMINE, GEPIA, Human Protein Atlas, and Kaplan–Meier plotter. We further verified the effect of significant biomarker on pancreatic cancer in vitro through functional experiment. Results: The Kaplan–Meier curve and log-rank test analyses showed a positive correlation between SMARCA1/2/3/SMARCAD1 and patients' overall survival (OS). On the other hand, mRNA expression of SMARCA6 (also known as HELLS) showed a negative correlation with OS. Meanwhile, no significant correlation was found between SMARCA4/5/SMARCAL1 and tumor stages and OS. The knockdown of HELLS impaired the colony formation ability, and inhibited pancreatic cancer cell proliferation by arresting cells at S phase. Conclusions: Data mining analysis and cell function research demonstrated that HELLS played oncogenic roles in the development and progression of pancreatic cancer, and serve as a poor prognostic biomarker for pancreatic cancer. Our work laid a foundation for further clinical applications of HELLS in pancreatic cancer. [ABSTRACT FROM AUTHOR]

Obesity, diabetes, hypertension and dyslipidemia are well-established risk factors for cardiovascular diseases (CVDs), and have been associated with exposure to persistent organic pollutants. However, studies have been lacking as regards effects of non-persistent pesticides on CVD risk factors. Here, we investigated whether background chronic exposure to polychlorinated biphenyls (PCBs) and multiclass pesticides were associated with the prevalence of these CVD risk factors in 502 Belgian and 487 Luxembourgish adults aged 18–69 years from the Nutrition, environment and cardiovascular health (NESCAV) study 2007–2013. We used hair analysis to evaluate the chronic internal exposure to three PCBs, seven organochlorine pesticides (OCs) and 18 non-persistent pesticides. We found positive associations of obesity with hexachlorobenzene (HCB), β-hexachlorocyclohexane (β-HCH) and chlorpyrifos, diabetes with pentachlorophenol (PCP), fipronil and fipronil sulfone, hypertension with PCB180 and chlorpyrifos, and dyslipidemia with diflufenican and oxadiazon, among others. However, we also found some inverse associations, such as obesity with PCP, diabetes with γ-HCH, hypertension with diflufenican, and dyslipidemia with chlorpyrifos. These results add to the existing evidence that OC exposure may contribute to the development of CVDs. Additionally, the present study revealed associations between CVD risk factors and chronic environmental exposure to currently used pesticides such as organophosphorus and pyrethroid pesticides. [Display omitted] • Hair analysis reveals associations between pollutant exposure and CVD risk factors. • Obesity was associated with both persistent and non-persistent pesticide exposure. • Diabetes was related to γ-HCH, PCP, PNP, fipronil, fipronil sulfone and oxadiazon. • Hypertension was associated with chlorpyrifos, fipronil, oxadiazon and diflufenican. • Dyslipidemia was related to chlorpyrifos, Cl 2 CA, trifluralin and diflufenican. [ABSTRACT FROM AUTHOR]

Introduction: The numbers of retrieved lymph nodes (RLNs) and positive lymph nodes (PLNs) had a significant impact on the survival of patients with ampulla of vater cancer (AVC), but the optimal numbers of the both were controversial. Objective: The cohort study aimed to explore the prognostic value and the optimal point of RLNs and PLNs for AVC. Methods: A total of 2347 AVC patients with M0 disease who underwent surgical resection and lymph node dissection from January 2004 to December 2013 were acquired from a prospective database. Results: The study found that the optimal cut-off values of RLNs were 18 in the N0 cohort and 16 in N1 or entire cohort due to the highest 5-year overall survival (OS) rate and disease-specific survival (DSS) rate and the separation of survival curves (all P < 0.05). In patients with RLNs ≥ 16, patients with PLN = 0 demonstrated significantly better 5-year OS and DSS rates (70.9% and 77.1%) compared to those with PLNs = 1–2 (41.6% and 44.7%; all P < 0.001), and patients with PLNs = 1–2 demonstrated significantly better 5-year OS and DSS rates (41.6% and 44.7%) compared to those with PLNs ≥ 3 (24.3% and 28.0%; all P < 0.001). Conclusions: This article recommended that at least 16 lymph nodes will improve the prognosis of AVC patients undergoing surgery. The best cut-off values of PLNs recommended for this study were 0 and 2, which may accurately stratify patients. [ABSTRACT FROM AUTHOR]

It is important to predict the capacity related parameters of reservoir such as brittleness, total organic carbon (TOC), in-situ stress, maturity of organic carbon (Ro), and buried depth in shale gas exploration and exploitation. Among these parameters, brittleness and TOC are especially important for shale gas exploitation. The complex resistivity measurement and analysis show that the rich organic shale in southern China features low resistivity and high chargeability. These characteristics are a geophysical prerequisite for predicting the sweet spot characteristic parameters of shale, such as TOC and brittleness, with rapid developing of high resolution controlled source electromagnetic (CSEM) method prospecting which can give resistivity and chargeability distribution of underground. Based on the rich organic shale composition analysis and complex resistivity measurements in southern China, this paper analysed the presence of pyrite as an associated mineral in organic-rich shale, and examined its relationship to resistivity, chargeability, TOC content and brittleness, and the quantitative relationship between the models has been established. Therefore, this study provides a firm experimental foundation for predicting parameters of shale sweet spots with CSEM prospecting. [ABSTRACT FROM AUTHOR]

In this study, we analyzed the geological, gravity, magnetic, and electrical characteristics of depressions in the Erlian Basin. Based on the results of these analyses, we could identify four combined feature parameters showing strong correlations and sensibilities to the reservoir oil-bearing conditions: the average residual gravity anomaly, the average magnetic anomaly, the average depth of the conductive key layer, and the average elevation of the depressions. The feature parameters of the 65 depressions distributed in the whole basin were statistically analyzed: each of them showed a Gaussian distribution and had the basis of Bayesian theory. Our Bayesian predictions allowed the definition of a formula to calculate the posterior probability of oil occurrence in the depressions based on the combined characteristic parameters. The feasibility of this prediction method was verified by considering the results obtained for the 22 drilled depressions. Subsequently, we were able to determine the oil-bearing threshold of hydrocarbon potential for the depressions in the Erlian Basin, which can be used as a standard for quantitative optimizations. Finally, the proposed prediction method was used to calculate the probability of hydrocarbons in the other 43 depressions. Based on this probability and on the oil-bearing threshold, the five depressions with the highest potential were selected as targets for future seismic explorations and drilling. We conclude that the proposed method, which makes full use of massive gravity, magnetic, electric, and geological data, is fast, effective, and allows quantitative optimizations; hence, it will be of great value for the comprehensive geophysical evaluation of oil and gas in basins with depression group characteristics. [ABSTRACT FROM AUTHOR]

Aims: Secondary grasslands reestablished after deforestation in subtropical and tropical regions greatly alter terrestrial carbon (C) and nitrogen (N) dynamics and their associated ecosystem functions. However, reliable evaluations of C and N dynamics in secondary grasslands across regional climatic gradient remain challenging. Methods: We investigated natural 13C and 15N abundance in plants and soil as well as their associations with environmental factors (including climatic, plant and edaphic variables) from 20 sites across a 600 km climatic gradient in secondary grasslands of southern China. Results: The δ13C values in plants and soil declined with increasing mean annual precipitation (MAP) but increased as the mean annual temperature (MAT) increased. These changes were mostly attributed to the shift in plant functional group between C4 and C3. In contrast, increasing MAP and decreasing MAT had positive effects on soil δ15N values, which were mainly related to changes in edaphic factors, including soil pH, soil C and N content and soil C:N ratios. Conclusions: Our findings indicate inverse patterns and different controls on soil δ13C and δ15N values along the climatic gradient, providing novel insights into the underlying mechanisms of ecosystem C and N dynamics in response to climate and vegetation change in secondary grasslands. [ABSTRACT FROM AUTHOR]

In order to realize the compressive stress and antifatigue manufacturing of titanium alloy TI-6Al-4V, a compound processing of longitudinal-torsional ultrasonic vibration and milling (LTUM) is proposed, a theoretical prediction model of machining-induced residual stress (RS) is established, and it is validated by experiments. The trajectory model of cutting edge in LTUM is constructed; furthermore, the undeformed chip thickness (UCT) model of LTUM is structured; The mechanical stress model of LTUM is established from the shear stress and plow stress; the thermal stress model of LTUM is established from shear thermal stress and plow thermal stress; Considering mechanical and thermal stress, the residual stress of longitudinal-torsional ultrasonic milling is established by loading and releasing stress. From numerical simulation of mechanical stress and thermal stress model, it shows that in LTUM, stress fluctuates with ultrasonic vibration, and mechanical stress absolute value is larger than that of traditional machining (TM); thermal stress absolute value is less than that of TM. A series of experiments are carried out to verify the RS model of LTUM. From present work, through theoretical prediction and experimental verification of machining-induced residual stress, it is concluded that established theoretical model predicts properties, and distribution of residual stress with high accuracy and the LTUM significantly increases surface compressive stress and compressive stress layer depth. It lays a foundation for the compressive stress and fatigue resistance of titanium alloys. [ABSTRACT FROM AUTHOR]

Traditional network MIMO systems with joint data processing usually require a large amount of backhaul data and a central processing station with very high processing power. In order to address this problem, the capacity of access network with network-enabled MIMO systems with distributed data processing is investigated in this paper. A study of network throughput for a system with interference mitigation and base station cooperation techniques is given. We also propose a distributed iterative decoding network structure as an alternative of joint detection/decoding scheme with network-enabled MIMO configurations, where iterative signal processing is performed at network level. Simulation results show that, with the proposed schemes, the complexity of data processing required to compute the detection solution is restricted and the complexity is distributed across access base stations, which results in a significant reduction in complexity of signal processing in hub base stations. [ABSTRACT FROM AUTHOR]

Background: Hepatocellular carcinoma (HCC) is a common primary malignant tumor which usually progresses to an advanced stage because of late diagnosis. Sorafenib (Sora) is a first line medicine for advanced stage HCC; however, it has been faced with enormous resistance. Simvastatin (Sim) is a cholesterol-lowering drug and has been reported to inhibit tumor growth. The present study aims to determine whether Sora and Sim co-treatment can improve Sora resistance in HCC. Methods: The HCC cell line LM3 and an established Sora-resistant LM3 cell line (LM3-SR) were used to study the relationship between Sora resistance and aerobic glycolysis. Cell proliferation, apoptosis and glycolysis levels were analyzed by western blotting, flow cytometry analysis and biomedical tests. A xenograft model was also used to examine the effect of Sim in vivo. Detailed mechanistic studies were also undertaken by the use of activators and inhibitors, and lentivirus transfections. Results: Our results demonstrated that the resistance to Sora was associated with enhanced aerobic glycolysis levels. Furthermore, LM3-SR cells were more sensitive to Sim than LM3 cells, suggesting that combined treatment with both Sora and Sim could enhance the sensitivity of LM3-SR cells to Sora. This finding may be due to the suppression of the HIF-1α/PPAR-γ/PKM2 axis. Conclusions: Simvastatin can inhibit the HIF-1α/PPAR-γ/PKM2 axis, by suppressing PKM2-mediated glycolysis, resulting in decreased proliferation and increased apoptosis in HCC cells, and re-sensitizing HCC cells to Sora. [ABSTRACT FROM AUTHOR]

For difficult-to-cut materials such as titanium alloy, a machining method of longitudinal-torsion ultrasonic-assisted milling (LTUM) was put forward to realize the anti-fatigue manufacturing, and cutting force, cutting temperature and residual stress (RS) were analyzed by 3D finite element simulation (FES). Firstly, based on thermal mechanical coupling, a 3D FES model of ultrasonic milling was established, the simulation of the cutting force, cutting temperature and RS were realized. Then, based on the 3D FES milling model, the milling process was equivalent to the oblique cutting model, it effectively improved the computation efficiency and realized longitudinal-torsional ultrasonic compound in milling process. Base on 3D equivalent model, compared with traditional milling (TM) and LTUM from the cutting force, cutting temperature and machined-induced RS. It is concluded that the LTUM effectively reduces the cutting force and cutting temperature, increases surface compressive stress and compressive stress layer depth. Furthermore, experiments were carried out to verify the equivalent model of LTUM, it shows that the simulated results are in agreement with experimental results, and predicts cutting force, cutting temperature and RS with high precision. [ABSTRACT FROM AUTHOR]

In recent years, the incidence of diseases associated with hepatic injury has increased in prevalence. Targeting the mitochondria to protect liver function has gained momentum due to their central role in energy production, apoptotic cell death, oxidative stress, calcium homeostasis, and lipid metabolism. In this study, we employed a hepatic mitochondria-based centrifugal ultrafiltration/liquid chromatography/mass spectrometry method (CM-HMC) to identify hepatic mitochondria ligands from medicinal herbs (MHs) including Notopterygii Rhizoma et Radix (NRR) that possess hepatic-protective effects. A total of 4 newly identified mitochondrial ligands were successfully identified by CM-HMC. The mitochondria-regulating activities of 3 of the 4 hits were confirmed using isolated mitochondria. The hepatic-protective effects of one of these hits were validated in carbon tetrachloride-damaged human liver L02 cell models. We have thus identified new natural hepatic-protectants that enhance our understanding of the hepatic-protective mechanisms of MHs. CM-HMC was proven to efficiently screen for mitochondrial ligands from MHs. [ABSTRACT FROM AUTHOR]

Ultrasonic horns are used in the ultrasonic-assisted milling and cutting tools. However, the interaction with tool end vibrations deteriorates the horn performance. In this study, the amplification coefficients and vibration node locations of an ultrasonic horn were determined via the 1D wave theory and optimized by the tool load effect account. By arranging spiral grooves at the straight part of the ultrasonic horn, a longitudinal-torsional modal converter was introduced. This made it possible to convert longitudinal vibrations into longitudinal-torsional coupled ones by the superposition of incident and reflected longitudinal waves with reflected transverse ones at grooves. Orthogonal L9 (33) tests with parameters of spiral grooves as variables were designed and conducted, and longitudinal-torsional ratios (LTR) of the milling tool end under different conditions were assessed using the commercial ANSYS software package. The in-depth analysis of simulation results implies that the LTR values are controlled by the following influence factors in the decreasing order: helical angle, number of grooves, and groove width. Single-factor tests indicate that LTR exhibits an initial drop and a further rise with the helical angle, attaining its minimal value at 30°; it drops with the number of grooves n, and remains practically unchanged with the groove width variation. Finally, the vibration tests of the proposed horn with the optimized parameters corroborated its feasibility and demonstrated its excellent performance in the ultrasonic-assisted milling tool application. [ABSTRACT FROM AUTHOR]

The accumulation of toxic bile acids (BAs) is closely related to liver injury, inflammation and tumorigenesis. The aim of the present study was to determine the role of the serum BA spectrum in the diagnosis and progression of liver cirrhosis. This was a prospective observational study involving patients with chronic hepatitis (n=23), liver cirrhosis (n=101), and cirrhosis complicated with hepatocellular carcinoma (CC-HCC; n=56). The 6-month survival of cirrhotic patients was recorded after blood collection. Comparisons of serum total BAs and individual BAs between different groups were performed using the Mann-Whitney U or Kruskal-Wallis tests. Correlation analysis was conducted by Spearman's correlation. Diagnosis and prediction analyses were performed using receiver operating characteristic curves. Survival was analyzed using the Kaplan-Meier method and multivariable Cox regression analysis. The concentrations of total BAs, glycocholic acid (GCA), glycochenodeoxycholic acid (GCDCA), taurocholic acid (TCA), taurochenoxycholic acid and tauroursodeoxycholic acid (TUDCA) were increased significantly in patients with early cirrhosis compared to patients with chronic hepatitis (P<0.05) and were associated with the diagnosis of cirrhosis (P=0.049, 0.004, 0.002, 0.003, 0.010 and 0.009, respectively). The levels of total BAs, primary conjugated BAs, and TUDCA increased as liver cirrhosis progressed (P<0.05). Serum total BAs, GCA, GCDCA, and TCA predicted the 6-month survival of patients with liver cirrhosis (P=0.0003, 0.005, 0.002, and 0.010 respectively). Based on multivariate Cox regression analysis, the level of total BAs was an independent predictor of mortality in cirrhotic patients (hazard ratios, 4.046; 95% CI, 1.620–10.108; P=0.003). In the early-stage cirrhosis group, the concentrations of total BAs and primary conjugated BAs were significantly elevated in patients with CC-HCC compared with patients with cirrhosis alone. In conclusion, total and individual BAs, especially primary conjugated BAs, are effective non-invasive markers in the diagnosis and prognosis of liver cirrhosis, and may be potential indicators in the occurrence of hepatocellular carcinoma in patients with early cirrhosis. [ABSTRACT FROM AUTHOR]

Objective. Liver fibrosis is a consequence of wound-healing responses to chronic liver insult and may progress to liver cirrhosis if not controlled. This study investigated the protection against liver fibrosis by isorhamnetin. Methods. Mouse models of hepatic fibrosis were established by intraperitoneal injection of carbon tetrachloride (CCl4) or bile duct ligation (BDL). Isorhamnetin 10 or 30 mg/kg was administered by gavage 5 days per week for 8 weeks in the CCl4 model and for 2 weeks in the BDL model. Protein and mRNA expressions were assayed by western blotting, immunohistochemistry, and quantitative real-time polymerase chain reaction. Results. Isorhamnetin significantly inhibited liver fibrosis in both models, inhibiting hepatic stellate cell (HSC) activation, extracellular matrix (ECM) deposition, and autophagy. The effects were associated with downregulation of transforming growth factor β1 (TGF-β1) mediation of Smad3 and p38 mitogen-activated protein kinase (MAPK) signaling pathways. Conclusion. Isorhamnetin protected against liver fibrosis by reducing ECM formation and autophagy via inhibition of TGF-β1-mediated Smad3 and p38 MAPK signaling pathways. [ABSTRACT FROM AUTHOR]

A feature of the Internet of Things (IoT) is that the data demanded users in the system need to be served with low energy consumption. To address this requirement, multi-input multi-output (MIMO) technology can be used in the communication modules. In this paper, a novel low-complexity parameter estimator combined with an MMSE detector and a constellation distance correction (CDC) structure is proposed for multiple antenna systems. A hard-output detector is proposed to enhance the reliability of the estimation output. By measuring the distance between constellation candidates and the MMSE estimated soft output, the proposed equalizer may avoid processing redundancy of candidates with decision distance. Simulation results show that the proposed MMSE-CDC technique may provide about the same BER performance as the other post detection processing (PDP) techniques but requires significant less computational complexity. [ABSTRACT FROM AUTHOR]

Highlights • The X-ray crystal structure of Ch KRED20/NAD+ complex was solved. • Three rounds of iterative saturation mutagenesis were performed. • Mutants with increased substrate acceptance toward aryl ketoesters were achieved. • One mutant had a k cat / K m 196-fold of the wild-type. • All three substrates were completely reduced at 100 g/l loading. Abstract Ch KRED20 is a robust NADH-dependent ketoreductase identified from the genome of Chryseobacterium sp. CA49 that can use 2-propanol as the ultimate reducing agent. The wild-type can reduce over 100 g/l ketones for some pharmaceutical relevant substrates, exhibiting a remarkable potential for industrial application. In this work, to overcome the limitation of Ch KRED20 to aryl ketoesters, we first refined the X-ray crystal structure of Ch KRED20/NAD+ complex at a resolution of 1.6 Å, and then performed three rounds of iterative saturation mutagenesis at critical amino acid sites to reshape the active cavity of the enzyme. For methyl 2-oxo-2-phenylacetate and ethyl 3-oxo-3-phenylpropanoate, several gain-of-activity mutants were achieved, and for ethyl 2-oxo-4-phenylbutanoate, improved mutants were achieved with k cat / K m increasing to 196-fold of the wild-type. All three substrates were completely reduced at 100 g/l loading catalyzed with selected Ch KRED20 mutants, and deliver the corresponding chiral alcohols with >90% isolated yield and 97 - >99%ee. [ABSTRACT FROM AUTHOR]

Talaromyces marneffei is the only dimorphic species in its genus and causes a fatal systemic mycosis named talaromycosis. Our previous study indicated that knockdown of AcuD gene (encodes isocitrate lyase of glyoxylate bypass) of T. marneffei by RNA interference approach attenuated the virulence of T. marneffei, while the virulence of the AcuD knockout strains was not studied. In this study, T. marneffei-zebrafish infection model was successfully established through hindbrain microinjection with different amounts of T. marneffei yeast cells. After co-incubated at 28°C, the increasing T. marneffei inoculum doses result in greater larval mortality; and hyphae generation might be one virulence factor involved in T. marneffei-zebrafish infection. Moreover, the results demonstrated that the virulence of the ΔAcuD was significantly attenuated in this Zebrafish infection model. [ABSTRACT FROM AUTHOR]

The fate of soil organic carbon (SOC) sequestered by afforestation is crucial for the mitigation of the anthropogenic climate change but remains largely unclear. This lack of knowledge is particularly true for SOC turnover driven by enzyme activity. Here we measured hydrolase (including β-glucosidase, α-glucosidase, cellobiohydrolase and xylanase) and oxidase (including polyphenol oxidase and peroxidase) activities in soil aggregates following 30-year afforestation in central China. We also analyzed the relationships of enzyme activities with SOC concentrations, soil C:nitrogen (N) ratios and δ 13 C values of soil organic pool (removing any carbonates by acid hydrolysis) and stable pool (NaOCl–resistant). Afforestation significantly enhanced soil β-glucosidase, α-glucosidase and xylanase activities in bulk soil, as well as SOC concentrations in bulk soil and all aggregate fractions compared to those in the open area and cropland. In particular, the woodland increased SOC concentration in >2000 μm macroaggregates by 4.2- and 3.2-fold, compared to the open area and cropland, respectively. Soil hydrolase activities were generally lower but SOC concentrations were higher in >2000 μm macroaggregates compared with those in other aggregate fractions following afforestation. Hydrolase activities were negatively correlated with SOC and C:N ratios in soil aggregate fractions following afforestation. Results of structural equation modeling indicated that the increasingly inhibited hydrolase activities with increasing soil aggregate size indirectly promoted SOC sequestration following afforestation. In addition, both hydrolase and oxidase were positively correlated with δ 13 C values in the stable pool of the afforested soils, confirming the essential role of enzymes for SOC turnover in soil aggregates following afforestation. Overall, our results highlight the importance of unevenly distributed enzyme activities among soil aggregates in regulating SOC sequestration following afforestation. [ABSTRACT FROM AUTHOR]

Nowadays, the reclamation of industrial waste acid characterized with low acid concentration and high metal ion content has attracted much attention. How to carry out effectively a separation between protons and metal ions becomes a top priority. In this report, a so-called proton permselective composite membrane was prepared specifically for waste acid reclamation by electrodialysis. Above all, a porous supporting membrane was prepared from polysulfone via classical wet phase inversion technology. Therein appropriate amount of sulfonated polysulfone (SPSF) was added to adjust its microstructure. Subsequently, a hydrophilic composite layer, such as Poly(ethylene imine) layer or Poly(vinyl alcohol) layer, was used to endow the proton permeability based on the unique transport mechanism of protons in which water molecules play an important role. ATR-FTIR and SEM were employed to monitor the changes in chemical composition and microstructure of as-prepared membranes, respectively. Furthermore, their electrodialytic transport properties, including electrical resistance, limiting current, water transport behaviors, proton permselectivity and anion-blocking ability, were investigated and compared with those of typical commercial cation-exchange membrane. As confirmed by series of electrochemical characterizations, as-prepared composite membranes, especially PVA-Series membranes, exhibited outstanding work performances and remarkable practical value in the acid recovery. At last, the ion substitution electrodialysis for waste acid reclamation in which typical composite membranes were assembled were also conducted to examine the process energy consumption, the concentration and purity of the produced acid. [ABSTRACT FROM AUTHOR]

Greater aridity predicted with climate change in drylands worldwide will affect soil nitrogen (N) cycling and the associated ecosystem functions. Despite >90% of soil N occurring in organic forms, the pathways of soil organic N (SON) turnover remain largely unknown in drylands, where biological activity is typically limited by water availability. Here we examined patterns of SON fractions and soil N-hydrolyzing enzyme activities across a 3700 km aridity gradient in arid and semiarid grasslands of northern China. We found that both the concentrations of all SON fractions and the proportion of more stable SON increased with increasing aridity index (AI, defined as mean annual precipitation/potential evapotranspiration). The largest SON fraction was hydrolysable NH 4 + in arid sites, but amino acid-N in semiarid sites. The activities of enzymes that hydrolyze relatively stable SON polymers (protease, peptidase, and N -acetyl-β-glucosaminidase) were negligible in arid sites (AI < 0.2), but increased significantly as AI increased in semiarid sites (AI > 0.2). Structural equation modeling indicated that the direct effect of microbial biomass on soil amidase was insignificant in arid sites, indicating that microbial SON turnover via enzymes is relatively weak. In semiarid sites, however, microbial biomass exerted significant direct positive effects on all soil N-hydrolyzing enzymes, suggesting strong microbial regulation of SON turnover via enzymatic mineralization. Altogether, our findings provide empirical evidence for divergent patterns of storage and turnover of SON between arid and semiarid grasslands. [ABSTRACT FROM AUTHOR]

Triclosan (TCS) is an antibacterial agent that is commonly used in personal care products. Because of its sediment-binding properties, TCS exposure presents a potential threat to sediment-dwelling aquatic organisms. Currently our knowledge of the fate and effects of sediment-associated TCS in aquatic systems is limited. To understand the impact of sediment-associated TCS, we used microcosms to assess effects of TCS exposure on a diverse range of organisms selected to mimic a subtropical community, with an exposure period of 28 days. We included the oligochaete freshwater worm Limnodrilus hoffmeisteri to evaluate the interaction between sediment-associated TCS and sediment-dwelling organisms, including potential loss of TCS from the sediment due to biological activity and bioaccumulation. Benthic macroinvertebrate presence significantly increased the TCS levels from 0.013 ± 0.007 μg/L to 0.613 ± 0.030 μg/L in the overlying water through biological activity, posing a potential additional risk to pelagic species, but it did not result in a significant reduction of the sediment concentration. Furthermore, worms accumulated TCS with estimated Biota-Sediment-Accumulation-Factors (BSAFs) ranging between 0.38–3.55. Other than for algae, TCS at environmental concentrations did not affect the survival of the introduced organisms, including the L. hoffmeisteri . Our results demonstrate that, although TCS at currently detected maximum concentration may not have observable toxic effects on the benthic macroinvertebrates in the short term, it can lead to bioaccumulation in worms. [ABSTRACT FROM AUTHOR]

This study proposes a replicon-based scheme for typing IncX plasmids into nine separately clustering subgroups, including IncX1α, IncX1β and IncX2–8. The complete nucleotide sequences of three IncX8 plasmids, namely pT5282-CTXM and p30860-NR from Enterobacter cloacae and p13190-KPC from Klebsiella pneumoniae , were determined and were compared with two other previously sequenced IncX8 plasmids (pCAV1043-58 and pCAV1741-16). These five plasmids possessed conserved IncX8 backbones with limited genetic variation with respect to gene content and organisation, and each of them carried one or three accessory modules that harboured resistance markers and metabolic gene clusters as well as transposons, insertion sequence (IS)-based transposition units and miniature inverted repeat transposable elements (MITEs), indicating that the relatively small IncX8 backbones were able to integrate various foreign genetic contents. The resistance genes bla CTX-M-3 and bla TEM-1 (β-lactam resistance), bla KPC-2 (carbapenem resistance) and Δ bla TEM-1 , and tet (A) (tetracycline resistance) and mph (E) (macrolide resistance) were found in pT5282-CTXM, p13190-KPC and pCAV1741-16, respectively, whilst p30860-NR and pCAV1043-58 carried no resistance genes. The data presented here provide an insight into the diversification and evolution history of IncX8 plasmids. [ABSTRACT FROM AUTHOR]

Soil nitrogen (N) availability is a major constraint for plant growth and consequently impacts soil carbon (C) sequestration following afforestation. The transformation of soil organic N to plant available form is predominantly catalyzed by N-hydrolyzing enzymes. Yet how N-hydrolyzing enzymes affect N availability for soil C sequestration under afforestation remains unclear. Here, we examined N-hydrolyzing enzyme activities, N masses (N contents in equivalent soil mass) and the δ 15 N values of total N (TN) pool and stable N pool (SN, NaOCl–resistant) in soil aggregates following 30 years of afforestation in subtropical China. The relationships of soil N mass and supply via enzymes with those of C were also developed. Afforestation increased TN masses and N-hydrolyzing enzyme activities, but declined the percentages of SN in TN and the δ 15 N values in soil aggregates. Soil TN mass was positively correlated with soil organic C mass in aggregates across land use types. Similarly, soil enzymes for N acquisition scaled isometrically with C acquisition with a slope of ∼1.0. Our results indicate that N constraint for soil C sequestration can be alleviated by increasing soil N-hydrolyzing enzyme activities combined with reducing SN:TN ratios and homeostatic ecoenzymatic C:N ratios following afforestation, which lead to tight coupling of soil N and C cycling. [ABSTRACT FROM AUTHOR]

Flame retardant treatment of epoxy resins (EP) to reduce their flammability for extending their range of applications attracts considerable attention. However, the synthesis process of conventional flame retardants is complicated and involves organic hazardous solvents. Meanwhile, how to ensure both the flame‐retardant and mechanical properties is a long‐standing and actual difficult problem. In this work, a supramolecular flame retardant (named ATPFR) is facilely created by one‐pot reaction, using cheap and accessible raw materials in an ecologically benign aqueous solvent. ATPFR is applied to improve the fire safety of EP. With only 5 wt% ATPFR addition, EP can reach the limiting oxygen index of 28.5% and the UL‐94 V‐0 rating with a significant "blow‐out effect." The cone calorimetry test reveals that the EP thermoset with 5 wt% ATPFR has a 75.8% reduction in the peak heat release rate (p‐HRR) and a 67.3% reduction in the peak smoke production rate (p‐SPR), respectively, compared with the pure EP. Additionally, EP composites with the small amount of ATPFR exhibit a slight decrease and maintain good mechanical properties. Therefore, the facile synthesis and application of this supramolecular flame retardant provide a reliable way for the construction of polymer materials with environment‐friendly and effective flame‐retardant system. [ABSTRACT FROM AUTHOR]

Background: The differential diagnosis of follicular thyroid carcinoma (FTC) and follicular adenoma (FA) before surgery is a clinical challenge. Many efforts have been made but most focusing on tumor cells, while the roles of tumor associated macrophages (TAMs) remained unclear in FTC. Here we analyzed the differences between TAMs in FTC and those in FA.Methods: We first analyzed the density of TAMs by CD68 immunostaining in 59 histologically confirmed FTCs and 47 FAs. Cytokines produced by FTC and FA were profiled using antibody array, and validated by quantitative PCR. Chemotaxis of monocyte THP-1 was induced by condition medium of FTC cell lines (FTC133 and WRO82-1) with and without anti-CCL15 neutralizing antibody. Finally, we analyzed CCL15 protein level in FTC and FA by immunohistochemistry.Results: The average density of CD68(+) cells was 9.5 ± 5.4/field in FTC, significantly higher than that in FA (4.9 ± 3.4/field, p < 0.001). Subsequently profiling showed that CCL15 was the most abundant chemokine in FTC compared with FA. CCL15 mRNA in FTC was 51.4-folds of that in FA. CM of FTC cell lines induced THP-1 cell chemotaxis by 33 ~ 77%, and anti-CCL15 neutralizing antibody reduced THP-1 cell migration in a dose-dependent manner. Moreover, we observed positive CCL15 immunostaining in 67.8% of FTCs compared with 23.4% of FAs.Conclusion: Our study suggested FTC might induce TAMs infiltration by producing CCL15. Measurement of TAMs and CCL15 in follicular thyroid lesions may be applied clinically to differentiate FTC from FA pre-operation. [ABSTRACT FROM AUTHOR]