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The insufficient supply of sugar units is the key limitation for the biosynthesis of glycosylated products. The unusual sugar TDP-L-mycarose is initially attached to the C3 of the polyketide erythronolide B, resulting in 3-O-a-mycarosylerythronolide B (MEB). Here, we present the de novo biosynthesis of MEB in Escherichia coli and improve its production using multi-strategy metabolic engineering. Firstly, by blocking precursor glucose-1-phosphate competing pathways, the MEB titer of triple knockout strain QC13 was significantly enhanced to 41.2 mg/L, 9.8-fold to that produced by parental strain BAP230. Subsequently, the MEB production was further increased to 48.3 mg/L through overexpression of rfbA and rfbB. Moreover, the CRISPRi was implemented to promote the TDP-L-mycarose biosynthesis via repressing the glycolysis and TDP-L-rhamnose pathway. Our study paves the way for efficient production of erythromycins in E. coli and provides a promising platform that can be applied for biosynthesis of other glycosylated products with unusual sugars. [ABSTRACT FROM AUTHOR]

The performance of hydrostatic turntables is strongly influenced by the geometry of oil pads. The properly designed structure of oil pads can reduce the power consumption of hydrostatic turntables and improves their service performance. A structural optimization of oil pads on a hydrostatic turntable based on particle swarm optimization is presented to improve the carrying performance and decrease energy costs. Using the finite difference method, the Reynolds equation is resolved to calculate the pressure distribution and flow rate in oil pads. The power cost of oil supply is determined according to the turntable working condition, and minimal energy consumption is set as the optimal solution. The geometrical parameters of the oil pad are chosen as individual elements that will converge to an optimal result by using PSO. [ABSTRACT FROM AUTHOR]

Timely and accurate extraction of urban land area using the Suomi National Polar-orbiting Partnership Visible Infrared Imaging Radiometer Suite (VIIRS) nighttime light data is important for urban studies. However, a comprehensive assessment of the existing methods for extracting urban land using VIIRS nighttime light data remains inadequate. Therefore, we first reviewed the relevant methods and selected three popular methods for extracting urban land area using nighttime light data. These methods included local-optimized thresholding (LOT), vegetation-adjusted nighttime light urban index (VANUI), integrated nighttime lights, normalized difference vegetation index, and land surface temperature support vector machine classification (INNL-SVM). Then, we assessed the performance of these methods for extracting urban land area based on the VIIRS nighttime light data in seven evaluation areas with various natural and socioeconomic conditions in China. We found that INNL-SVM had the best performance with an average kappa of 0.80, which was 6.67% higher than the LOT and 2.56% higher than the VANUI. The superior performance of INNL-SVM was mainly attributed to the integration of information on nighttime light, vegetation cover, and land surface temperature. This integration effectively reduced the commission and omission errors arising from the overflow effect and low light brightness of the VIIRS nighttime light data. Additionally, INNL-SVM can extract urban land area more easily. Thus, we suggest that INNL-SVM has great potential for effectively extracting urban land with VIIRS nighttime light data at large scales. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate vascular endothelial apoptosis, and the regulatory molecules involved in the condition of heatstroke caused by direct hyperthermia due to high core temperature and gut-derived endotoxemia. Human umbilical vascular endothelial cells (HUVECs) were isolated and treated with heat stress (43°C for 1 h), lipopolysaccharide (LPS; 1 μg/ml), or a combination of heat stress pretreatment followed by LPS. Caspase-3 activity, DNA fragmentation, and cell viability, determined using a 3-(4, 5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay, were measured to examine cellular apoptosis. Changes in the expression levels of heat shock protein (HSP) 27, HSP90 and B-cell lymphoma 2 (Bcl-2), and the phosphorylation of p38 were detected using Western blot assays. The specific inhibitor of p38, SB203580, was also used. LPS induced endothelial apoptosis, as indicated by increased caspase-3 activity, a high level of DNA fragmentation and low cell viability. LPS also increased p38 phosphorylation and decreased the expression levels of HSP27, HSP90 and Bcl-2. Heat stress pretreatment inhibited LPS-induced cellular apoptosis, increased the phosphorylation of p38, and increased the expression levels of HSP27, HSP90 and Bcl-2. Pretreatment with SB203580 had effects similar to those of heat stress in the amelioration of LPS-induced effects. These findings demonstrated that heat stress pretreatment decreased LPS-induced Bcl-2-associated apoptosis in HUVECs by attenuating p38 activation, thereby increasing the expression levels of HSP27 and HSP90. [ABSTRACT FROM AUTHOR]

The precision of the contact model for a joint interface strongly depends on the fractal dimension and fractal roughness coefficient. In this paper, an improved deep neural network method was adopted to predict the surface appearance parameters. In order to meet the high accuracy requirements for the prediction results of the contact model, a novel surface appearance prediction model was established utilizing a regularized deep belief network. The Bayesian regularization strategy was used to reduce the network weights during unsupervised training, which can effectively restrain the contribution of unimportant neurons. This allows to limit the occurrence of overfitting, and the layer-by-layer training was performed for each hidden layer based on a continuous transfer function. Meanwhile, the surface appearance parameters of the joint interface could be obtained by plugging arbitrary machining parameters into the training model. The specific contact model was then established based on fractal theory by applying the above-mentioned prediction results. The parameters of the joint interface were used to simulate the frequencies and vibration modes of frame-shaped structural parts. The contact model was validated by comparing the simulation results with experimental data. The proposed model is expected to provide a theoretical basis for optimizing the structure and improving the accuracy of computerized numerical control machines. [ABSTRACT FROM AUTHOR]

During work or long-term storage, grease is susceptible to thermal oxygen or mechanical aging, which affects the performance of grease or even leads to the destruction of the structural surface of grease lubricated products. As the main mechanism of grease lubrication, grease partitioning can explore the aging law of grease and effectively identify whether the grease fails. In this paper, 7014 aerospace grease was selected as the research object and accelerated test was conducted by high temperature thermal oxygen. The combination of grease separation degree and mass change rate was selected for comprehensive characterization of grease separation performance. The results show that the grease partitioning degree has a significant decreasing trend; the quality change has also decreased and the degradation trajectory is similar to the partitioning degree; it is inferred that the main reason for the decrease of grease partitioning performance may be the loss of base oil and the change of thickener fiber structure. [ABSTRACT FROM AUTHOR]

This paper demonstrates a versatile, facile and low-cost precipitate transformation method to synthesize ZnO/ZnS/MxS (metal sulfide) core/shell/shell (CSS) nanorods (NRs), including ZnO/ZnS/Ag2S, ZnO/ZnS/CuS, ZnO/ZnS/Cu2S, ZnO/ZnS/CdS and ZnO/ZnS/Bi2S3. The sufficient differences between the solubility product constants of ZnO, ZnS and MxS allow ZnO NRs to be converted to ZnO/ZnS and ZnO/ZnS/MxS nanostructures via an intermediary conversion route based on the ion-by-ion growth mechanism. The photocurrent density and efficiency for hydrogen generation of the ZnO/ZnS/Ag2S CSS nanostructure are measured to be up to 15.28 mA cm-2 and 15.92%, respectively, which is, to the best of our knowledge, the highest value ever reported for ZnO-based nanostructures. It is believed that these enhanced performances are attributed to the improved absorption efficiency and desirable gradient energy gap structure. In comparison with some other similar CSS NRs (i.e. ZnO/ZnS/CuS, ZnO/ZnS/Cu2S, ZnO/ZnS/CdS and ZnO/ZnS/Bi2S3) that are successfully prepared through the same method, ZnO/ZnS/Ag2S CSS NR is found to provide the best photoelectrochemical performance. [ABSTRACT FROM AUTHOR]

Abstract: By employing first principle and a quasi-harmonic Debye model, we study the phase stability, phase transition, electronic structure and thermodynamic properties of cadmium sulfide (CdS). The results indicate that CdS is a typical ionic crystal and that the zinc-blende phase in CdS is thermodynamically unstable. Moreover, the heat capacity of the wurtzite and rocksalt phases of CdS decreases with pressure and increases with temperature, obeying the rule of the Debye T 3 law at low temperature and the Dulong–Petit limit at high temperature. [Copyright &y& Elsevier]

One of the main differences between sentiment and infectious diseases is that the former one has two opposite infectious states: positive (optimistic) and negative (pessimistic), while the latter one has not. In this paper, based on the SISa model, we consider this issue and propose a new model of sentiment contagion called the SOSa-SPSa model. The results of both numerical and agent-based simulations show that our model could explain the process of sentiment contagion better than that of Hill et al. (2010). Further analysis shows that both the numbers of optimistic and pessimistic individuals will increase with the probability of spontaneity or contagion and decrease with the probability of recovery. Potential applications of this model in financial market have also been discussed. [ABSTRACT FROM AUTHOR]

Much literature finds that the skewness in the return distribution is negatively correlated with the risk premium coefficient, and speculation is the reason for the skewness in the return distribution. As further research, this paper, first taking up the time-varying property of the risk premium coefficient, proposes a GARCH-M model with a time-varying coefficient of the risk premium for an empirical study of the correlation between the conditional skewness in the return distribution and the time-varying risk attitude. The empirical study indicates that the coefficient of the risk premium varies with the time, and even in a mature market the conditional skewness in the return distribution is negatively correlated with the time-varying coefficient of the risk premium. [ABSTRACT FROM AUTHOR]

Current research on the impact of social interaction on the stock market participation only involves the traditional way of social interaction, and this paper further investigates the modern social interaction effects on the stock market participation and its activeness. The sample containing 150 Chinese counties is selected, and we apply grouping analysis and linear regression to conclude that social interaction has positive influence on the stock market participation and its activeness. Both traditional and modern social interaction ways affect the stock market participation and its activeness to the similar extent, so modern social interaction is of the same importance. Controlling for the respondents' age, wealth, and education level, the above conclusion still holds. [ABSTRACT FROM AUTHOR]

The novel method of an analogous beam is studied, which the flexural rigidity and mass per unit length correspond was described as the reciprocal of the mass per unit and the reciprocal of the flexural rigidity of the beam. It is shown that both beams possess the same natural frequencies of flexural vibration. In order to approximate calculation of these frequencies, the continuously distributed mass of the original beam is substituted for a number of concentrated masses. The analogous beam then becomes a chain of rigid links connected by pins and equipped with springs restraining the relative rotation of adjacent links. The equations of motion for the analogous beam can be solved by a procedure which consists of assuming a value for the natural frequency and calculating the deflections successively from one end of the beam to the other. Under normal circumstances, there will be a certain error, and one boundary condition will not be satisfied. The procedure is repeated with different values of the frequency until the error is removed. The method is illustrated by an example of a Crossbeam for which the fundamental frequency is found. [ABSTRACT FROM AUTHOR]

The effect of monorhamnolipid (monoRL) on the degradation of n-hexadecane by Candida tropicalis was investigated in this study. The concentration of hexadecane, cell growth, cell surface hydrophobicity (CSH), cell surface zeta potential (CSZP), and FT-IR spectra of cellular envelope were tested to determine the mechanisms. MonoRL at the initial concentrations of 11.4, 19, and 38 mg/l improved the degradation of hexadecane, and 19 mg/l was the best concentration. However, 114 mg/l monoRL suppressed the biodegradation probably because of the reduced bioavailability of hexadecane caused by the micelles. The presence of monoRL changed the cell surface properties, which was demonstrated by the increased CSH, the increased CSZP, and the changed FT-IR spectra of cellular envelope at 680 and 620 cm. The changes of cell surface properties may be a reason for the enhanced biodegradation of hexadecane by the yeast. The results indicate the potential application of monoRL in the bioremediation of hydrocarbons. [ABSTRACT FROM AUTHOR]

Oriented ZnO nanorods were fabricated in a two-step approach, including the synthesis of seed layer on different substrates and the growth of ZnO nanorods in aqueous solutions of zinc nitrate and hexamethylenetetramine at low temperature. The effects of seed layer synthesized by different methods, sol–gel method and electrochemical deposition method, on the orientation and morphologies of ZnO nanorods were compared in detail. The optimal parameters for the growth of highly oriented ZnO nanorod arrays were found and the forming mechanism was also disclosed. Furthermore, as an application of the ZnO nanorod film, dye-sensitized solar cells based on it were successfully fabricated. The cell performances of ZnO nanorods grown on ED-ZnO seed layer deposited at −700 mV were higher than those with SG-ZnO seed layer due to good nanostructure. [ABSTRACT FROM AUTHOR]

Although product design methods are well developed, the recent rise of environmentally conscious design, which includes materials selection as a key element, mandates the development of new engineering tools for decision-making. In this investigation, a method for establishing a life cycle environmental performance index is developed; it is envisioned that the index can be integrated into an environmentally conscious design process. The method addresses such traditional design factors as structural constraints and incorporates an additional consideration, the life cycle environmental impact. The method is applied to the design of an air conditioner support plate. In this application, it is desired to select a material that provides minimal environmental impact, subject to stiffness and strength constraints. Pareto optimization is adopted to analyze the results. The case study shows that the decision-making analysis can provide design guidelines and a criterion for materials selection to achieve environmentally conscious design. [ABSTRACT FROM AUTHOR]

The size and distribution of the contact stress at the assembly interface will directly affect the connection performance of the mechanical joint. However, the rough assembly interface presents strong dielectric discontinuity and material nonlinearity, which become the bottleneck restricting the development of contact stress detection. How to obtain contact stress by nondestructive testing means has become an urgent problem to be solved. In this paper, a multi-layer interface contact stress detection method based on contact acoustic resistance model is proposed to solve the difficult problem of rough interface contact stress detection. Firstly, based on the formation mechanism of contact acoustic resistance of rough assembly interface, the equivalent contact acoustic resistance expression of contact layer is derived. Secondly, the contact mechanism of rough assembly interface is clarified, and the mapping relationship model between contact acoustic resistance and contact stress is constructed. On this basis, according to the transmission law of ultrasonic wave at different interfaces of multilayer acoustic impedance, the expression of acoustic transmission coefficient at the interface of variable acoustic impedance is obtained. A contact stress detection method based on contact stress-contact acoustic resistance coefficient and acoustic transmission coefficient is proposed. The correctness of the theoretical model is verified by the tensile testing machine, and the maximum error is 15.52 %. This method will provide powerful data support for the evaluation of assembly interface connection state. [ABSTRACT FROM AUTHOR]

Streaming proton and alpha particles are permeating in the solar wind and solar atmosphere. These particles considerably affect the normal waves in electron–proton–alpha plasmas, especially inducing electrostatic and electromagnetic ion/ion beam instabilities. This paper gives a comprehensive investigation on stable and unstable parallel-propagating wave modes in plasmas with streaming proton and alpha particles. It illustrates that at a large beam velocity condition, the backward-propagating fast-magnetosonic/whistler wave (Alfvén/proton-beam or Alfvén/alpha beam mode wave) turns to forward propagation in the core proton rest frame, and couples with forward-propagating Alfvén/alpha-cyclotron and alpha-cyclotron/proton-cyclotron waves (fast-magnetosonic/whistler wave), triggering Alfvén/proton-cyclotron and fast-magnetosonic/whistler instabilities. Furthermore, as perpendicular thermal pressures of proton and alpha beams are larger than their parallel thermal pressures, several new electromagnetic instabilities arise in the case of the low ion streaming velocity, where both Alfvén/proton-cyclotron and fast-magnetosonic/whistler instabilities are stable. This paper also predicts the possible ion/ion electromagnetic instabilities in solar coronal holes, which can give a constraint on the ion differential drift velocity therein. [ABSTRACT FROM AUTHOR]

BACKGROUND: Heatstroke has become a common emergency event in hospitals. Procalcitonin PCT) is used as a biomarker of infection in the emergency department (ED), but its role in rhabdomyolysis RM) following exertional heatstroke (EHS) remains unclear. METHODS: A retrospective cohort study enrolled patients with EHS from the intensive care unit ICU). We collected RM biomarkers, inflammation markers, critical disease scores at admission, 24 48 h, and discharge, and 90-day mortality. Correlation analysis, linear regression and curve fitting were used to identify the relationship between PCT and RM. RESULTS: A total of 162 patients were recruited and divided into RM (n=56) and non-RM (n=106) groups. PCT was positively correlated with myoglobin (Mb), acute hepatic injury, disseminated intravascular coagulation (DIC), Sequential Organ Failure Assessment (SOFA) score, and Acute Physiology and Chronic Health Evaluation II (APACHE II) score, with correlation coefficients of 0.214, 0.237, 0.285, 0.454, and 0.368, respectively (all P<0.05). Interestingly, the results of curve fitting revealed a nonlinear relationship between PCT and RM, and a two-piecewise linear regression model showed that PCT was related to RM with an odds ratio of 1.3 and a cut-off of <4.6 ng/mL. Survival analysis revealed that RM was associated with higher mortality compared to non-RM cases (P=0.0093). CONCLUSION: High serum PCT concentrations are associated with RM after EHS in critically ill patients. Elevated PCT concentrations should be interpreted cautiously in patients with EHS in the ED. [ABSTRACT FROM AUTHOR]

Poly(vinylphosphonic acid) (PVPA) cross-linked networks on Ti6Al4V show superlubricity behavior when sliding against polytetrafluoroethylene in water-based lubricants. The superlubricity can occur but only with the existence of salt ions in the polymer cross-linked networks. This is different from the phenomenon in most polymer brushes. An investigation into the mechanism revealed that cations and anions in the lubricants worked together to yield the superlubricity even under harsh conditions. It is proposed that the preferential interactions of cations with PVPA molecules rather than water molecules are the main reason for the superlubricity in water-based lubricants. The interaction of anions with water molecules regulates the properties of the tribological interfaces, which influences the magnitude of the friction coefficient. Owing to the novel cross-linked networks and the interactions between cations and polymer molecules, their superlubricity can be maintained even at a high salt ion concentration of 5 M. These excellent properties make PVPA-modified Ti6Al4V a potential candidate for application in artificial implants. [ABSTRACT FROM AUTHOR]

In the electrical discharge machine (EDM), the slide carriage system of the x axis connects the lathe bed and the ram of the Y axis, its thermal-deformation has a directly effect on machining precision. Based on Solid-works and ANSYS Workbench software to build the finite element model (FEM) of the slide carriage system, the heat generation of the motor on the x axis, and the frictional heat of the bearing and guide as the main thermal source, there are two cases: applied and no contact thermal resistance (TCR) as the thermal-structure coupling deformation analysis. Established a model of the natural convection heat transfer coefficient with the temperature-change according to the actual measured the temperature curve of workshop and mathematical logarithm principle. The analysis told us that: in the thermal analysis of precision mechanical equipment, heat source comes from the external environment temperature and motor heat production, at the same time, the contact thermal resistance and the natural convection heat transfer coefficient with the temperature-change for the thermal characteristics of the equipment will make an important influence. [ABSTRACT FROM AUTHOR]

Calpains are a family of cysteine proteases, implicated in a wide range of cellular calcium-regulated functions. Evidence from previous studies using an inhibitor of calpain indicates that calpain activation is involved in the process of numerous inflammation-associated diseases. As a result of in-depth studies, calpains have been proposed to influence the process of inflammation via a variety of mechanisms. The aim of the present study is to provide an overview of recent reports regarding the role of calpain in the process of inflammation, including regulation of immune cell migration, modulation of the activation of inflammatory mediators, degradation of certain associated proteins and induction of cell apoptosis. Understanding these mechanisms may contribute to the investigation of novel therapeutic targets for inflammation-associated diseases. [ABSTRACT FROM AUTHOR]

We investigated the nonlinear elastic characteristic of an in-arm hydropneumatic suspension unit (ISU) as well as the damping characteristic of the controllable vane absorber. Due to the strong nonlinear characteristic of the ISU, simplify is needed to accurately model the vehicle. Based on the theory of multibody dynamics, a virtual prototype of the tracked vehicle was built, which includes the hydraulic system, the multi-dynamics of running gears and a road surface model. The virtual prototype is validated using both a static balancing test and a stiffness characteristics test. By simulating the road impact loading of the tracked vehicle when travelling on a trapezoidal US military road, the changes of the pitch angle and the acceleration of seats and centroid of the tracked vehicle was analyzed for two different damping ratios. We also determined key ride indicators for different speeds. The stiffness and damping characteristics of the ISU were tested in a bench experiment. [ABSTRACT FROM AUTHOR]

Translocation of 14-3-3 protein epsilon (14-3-3ε) was found to be involved in Triptolide (Tp)-induced inhibition of colorectal cancer (CRC) cell proliferation. However, the form of cell death induced by 14-3-3ε translocation and mechanisms underlying this effect remain unclear. This study employed label-free LCMS/ MS to identify 14-3-3ε-associated proteins in CRC cells treated with or without Tp. Our results confirmed that heterogeneous nuclear ribonucleoproteins C1/C2 (hnRNP C) were exported out of the nucleus by 14-3-3ε and degraded by ubiquitination. The nucleo-cytoplasmic shuttling of 14-3-3ε carrying hnRNP C mediated Tp-induced proliferation inhibition, cell cycle arrest and autophagic processes. These findings have broad implications for our understanding of 14-3-3ε function, provide an explanation for the mechanism of nucleo-cytoplasmic shuttling of hnRNP C and provide new insights into the complex regulation of autophagy. [ABSTRACT FROM AUTHOR]

Accuracy of machine tool with a gantry frame is reduced due to the vibration caused by inertial force impact. Hydrostatic slider bearings are considered as key structures of machine tools, which play an important role in improving impact and vibration resistance ability as dynamic performance. In this work, an incline model which combines bending deformation with linear displacement is simulated using working conditions of the straddle carrier under inertial force impact as an imitation of vibration amplitude. Using finite difference method (FDM), numerical solution of pressure distribution in oil pad can be determined by solving the Reynolds equation. Relationship between carrying capability and incline extent can be determined by analyzing the resolution of the Reynolds equation. A new type of oil pad size optimizing process is propose in this work, which is carried out based on the analysis of the analyzing result to enhance the inertial force resistance ability. Finally, impact resistance capacity of machine tool can be improved by sacrificing oil film thickness. [ABSTRACT FROM AUTHOR]

In five-axis machine tools, a rotary table is often used as a means for providing rotational motion and supporting the workpiece. Its rigidity, precision and carrying capacity is directly related to the machining ability and the accuracy of the NC machine tool. Traditional rotary table design is normally performed by teams, each with expertise in a specific discipline, which causes excessive iterations and cannot provide users with products of reliable working performance and bearing capacity. To achieve an optimal design with less cost and better performance, this paper considers the mutual interaction of hydrostatics and structure disciplines involved in the design of hydrostatic rotary tables, and a sensitivity-based multidisciplinary optimal design procedure of a hydrostatic rotary table is proposed. Sensitivity analysis is adopted to identify the key design parameters that have a major influence on the performance of rotary tables to improve the convergence of optimization process. The constrained multi-objective optimization problem is solved by using a particle swarm optimization approach. A hydrostatic rotary table of a five-axis heavy duty machine tool is selected as an illustration example. The results show that the proposed method can realize the multidisciplinary optimization resulting in a rotary table of good rigidity and bearing capacity [ABSTRACT FROM AUTHOR]

Pre-loading, both in terms of application method and actual applied force, significantly affects the stiffness and natural frequency of a high speed spindle system. The gyroscopic moment at high speed leads to whirling of the spindle, and the whirl frequency is not equal to the system's natural frequency. To discover the relationship between pre-load and whirl frequency, theoretical and experimental research was undertaken. Two numerical models of the angular contact ball bearings, based on rigid and constant pre-load mechanisms, were established. The shaft is considered as a set of Timoshenko beam elements, and gyroscopic moment and centrifugal force are both considered. Adding bearing stiffness in the form of springs to this finite element system produced a spindle-bearing coupled model. Iteration was used to deduce the interactions among bearing groups. The exact whirl frequency of a spindle subjected to different pre-load mechanisms has been calculated. To validate the proposed theory, frequency analysis was carried out on a Siemens CAT40 spindle. Experimental results agreed with theoretical calculations. The result shows that speed had a great influence on bearing stiffness and spindle whirl frequency. Adopting a reasonable pre-load method and pre-load force improved the spindle critical frequency. [ABSTRACT FROM AUTHOR]

Intrahepatic cholestasis represents a heterogeneous group of disorders that begin during childhood, most commonly manifesting as neonatal cholestasis, and lead to ongoing liver dysfunction in children and adults. For children, inherited pathogenic factors of cholestasis have gained increasing attention owing to the rapid development of molecular biology technology. However, these methods have their advantages and disadvantages in terms of simplicity, sensitivity, specificity, time required and expense. In the present study, an effective, sensitive and economical method is recommended, termed high-resolution melting (HRM) analysis and direct sequencing, based on general polymerase chain reaction, to detect mutations in disease-causing genes. As one type of inherited intrahepatic cholestasis, progressive familial intrahepatic cholestasis type 2 (PFIC2) is caused by pathogenic mutations in the ABCB11 gene, HRM was used to detect mutations in the ABCB11 gene in the present study, and the diagnosis for PFIC2 was made by comprehensive analysis of genetic findings and clinical features. Furthermore, the characteristics of mutations and single nucleotide polymorphisms (SNPs) in the ABCB11 gene were elucidated. A total of 14 types of mutations/polymorphisms were identified in 20 patients from mainland China, including six missense mutations (p.Y337H, p.Y472C, p.R696W, p.Q931P, p.D1131V and p.H1198R), one nonsense mutation (p.R928X) and seven SNPs (p.D36D/rs3815675, p.F90F/rs4148777, p.Y269Y/rs2287616, p.I416I/rs183390670, p.V444A/rs2287622, p.A865V/rs118109635 and p.A1028A/rs497692). Five mutations were novel. The majority of the mutations were different from those detected in other population groups. A total of 4/20 patients (1/5) were diagnosed to be PFIC2 by combining genetic findings with the clinical features. Polymorphisms V444A and A1028A, with an allele frequency of 74.5 and 67.2%, respectively, were highly prevalent in the mainland Chinese subjects. No differences were found between the patients with cholestasis and the control subjects. Efficient genetic screening facilitates the clinical diagnosis of genetic disorders. The present study demonstrated that HRM analysis was efficient and effective in detecting mutations and expanded the known spectrum of ABCB11 gene mutations. [ABSTRACT FROM AUTHOR]

Johanson-Blizzard syndrome is a very rare autosomal recessive disorder caused by mutations in the Ubiquitin-Protein Ligase E3 Component N-Recognin 1 (UBR1) gene. The syndrome is characterized by exocrine pancreatic insufficiency and a wide range of additional clinical features, including aplasia or hypoplasia of the alae nasi, oligodontia, sensorineural hearing loss, hypothyroidism, scalp defects, mental retardation, and developmental delay. Several other abnormalities in different organs, particularly anorectal, urogenital, and cardiac anomalies have been reported since the first description of this syndrome four decades ago. UBR1 gene defects are underlying the disease. Only symptomatic treatment is available. Exocrine pancreas insufficiency plus abnormal alae nasi is pathognomonic for Johanson-Blizzard syndrome. [ABSTRACT FROM AUTHOR]

The adsorption of NO2molecules on a series of zigzag (n,0) single-walled carbon nanotubes (SWNTs) (n 6-12) have been investigated by first-principles methods. The results indicate that the tube diameter and the concentration of NO2gas determine the interactions between NO2molecules and the tube. The chemisorption of a single NO2is only possible for the tube with a small diameter (n< 10), while the second NO2molecule can be chemisorbed for all tubes studied here. The additions of more NO2molecules in different patterns have also been considered for a (8,0) tube, and the NO2groups prefer the pair arrangement with stronger binding energy. According to the results of band structure calculations, overall, the SWNT exhibits a p-type response upon exposure to NO2gas and the electron charge transfer is an important reason for explaining the enhancement of conductivity of the tube. Moreover, it is interesting that, accompanied by charge transfer, the chemisorption of NO2also leads to the radical transfer from the NO2group to the carbon atoms at the ortho and para sites of the six-membered ring. As a result, the SWNT possesses the radical characteristic, which facilitates the further functionalization of the tube wall. [ABSTRACT FROM AUTHOR]

Objective: Rhabdomyolysis (RM) in exertional heatstroke (EHS) often leads to multiple organ dysfunction including acute kidney injury (AKI). Studies have shown that serum creatine kinase (CK) >1000 U/ L as a serological diagnostic criterion for RM does not reflect the risk of AKI or mortality. Methods: This longitudinal cohort study included all patients with EHS who were admitted to intensive care unit between January 2008 and June 2019. Serum myoglobin (sMb) was studied as the serological marker of RM and compared with CK. Outcome events were AKI and 90-day mortality. Results: A total of 161 patients were enrolled, of whom 52 (32.3%) had sMb ≥1000 ng/mL. Patients with sMb ≥1000 ng/mL had higher SOFA score, higher APACHE II score, lower GCS score, and higher incidence of disseminated intravascular coagulation, acute myocardial injury, acute liver injury, AKI, and 90-day mortality than patients with sMb <1000 ng/mL. Lymphocytes, neutrophils, D-Dimer were risk factors for AKI in patients with sMb ≥1000 ng/mL. Curve fitting showed a curved relationship between sMb and EHS-induced AKI but not CK. sMb ≥1000 ng/mL showed better predictive ability for AKI (area under curve: 0.786). APACHE II, SOFA, and GCS scores were risk factors for 90-day mortality in patients with sMb ≥1000 ng/mL. Conclusion: Serum myoglobin is a better predictor of AKI and 90-day mortality than CK in patients with RM after EHS. [ABSTRACT FROM AUTHOR]

Studies have indicated that reducing the process energy demand is as important as improving the energy conversion efficiency to make manufacturing equipment more energy efficient. However, little work has been done to understand the energy demand characteristics of the widely employed drawing process. In this paper, the energy demand of the cylindrical drawing process under a range of operating parameters was measured and analyzed. Since any energy saving efforts should not have negative effects on the product quality, the forming quality of the drawn part indicated by the maximum thinning and thickening ratios and variation of thickness was also considered. To identify the main contributors to energy demand and forming quality, two sets of experiments were designed based on the Taguchi method. The first set of experiments include three parameters (i.e., punch velocity, blank holder force, and drawn depth) at three levels, while the second set of experiments only include two factors (i.e., punch velocity and blank holder force) at three levels due to their impacts on the forming quality. Analysis of variance (ANOVA) and analysis of means (ANOM) were then used to analyze the experimental results. Finally, grey relational analysis (GRA) was used to reveal the correlation between the forming quality and the process energy. Results show that the mean thickness variation has the strongest relational grading with the process energy, which suggests that the process energy can be used as an effective indicator to predict mean thickness variation of the drawn part. The identified characteristics of the process energy and the forming quality can be used to select process parameters for reduced energy demands of drawing processes. [ABSTRACT FROM AUTHOR]

As energy efficiency increases in importance, researchers have identified manufacturing processes as opportunities where energy consumption can be reduced. Drawing is one widely employed, energy intensive manufacturing process, which could benefit by analysis of energy consumption during operation. To optimize the energy consumption of the drawing process, this paper developed an explicit model to quantify the process energy for the cylindrical drawing process by analyzing the dynamic punch force during the process. In this analysis, the evolution of the stress and strain was analyzed in the drawn part by considering all the structure parameters of the drawn part. The stress and strain analyses were integrated into an overall process energy model, and the behavior of the model was classified into three categories, based on their physical mechanisms, i.e., deformation energy, bending energy, and friction energy. The model was validated using numerical experiments designed by the Taguchi method where two different kinds of materials were tested over 18 runs. The results from the numerical experiments were compared with those from the model, and show that the maximum variation of the process energy predicted by this model is less than 10% for a given part. Sensitivity analysis was performed on the model to understand the contributions of the process parameters on the process energy to guide process optimization for lower energy consumption. The established model can assist in the rapid design of drawn parts with lower embodied energy. [ABSTRACT FROM AUTHOR]

Hydraulic presses are widely applied in various forming processes to manufacture products with complex shapes, however, they are energy-intensive. In order to lower the energy consumption, a variable-speed variable-displacement pump unit (SVVDP) was developed for hydraulic presses, where the flow rate required by the press in a forming process can be realized by changing the motor rotating speed and the pump displacement simultaneously. A theoretical model was built to reveal the energy dissipation behavior of the drive unit, which shows that the energy efficiency of the drive unit can be optimized by varying the rotating speed of the motor under a variety of load conditions. An experimental platform with a SVVDP was established to find the optimum rotating speed and the corresponding displacement in different load conditions, and experimental results verified the improved energy efficiency of the SVVDP compared with that of the commonly used single variable drive unit. By employing the strategy that the determined optimum rotating speeds in different load conditions were preset as recommended values for the drive unit working in different operations, the proposed drive unit was applied to a press completing a forming process and the results indicate significant energy saving potentials. [ABSTRACT FROM AUTHOR]

Tribology experiments using AISI 1045 carbon steels are used to investigate the tribo-magnetisation phenomenon and a new method for monitoring the wear state during friction is proposed. Variation in the magnetic memory signals on the wear surface of ferromagnetic material is studied. The results show that, in the testing direction parallel to the sliding and after removing wear debris during the severe wear stage, the distance between the trough features of the tangential component Hp(x) and that between the peak features of the gradient K of the normal component Hp(y) can provide the length of the wear area. Moreover, in the testing direction normal to the sliding, the tangential component Hp(x) shows obvious V-shape features, while the normal component Hp(y) has peak-trough features, which could also be used to estimate the width of the wear area. The tribology parameters and magnetic signal characteristics are also quantitatively correlated. The wear loss, m, increases exponentially with an increase in the maximum gradient Kmax of Hp(y), while the friction coefficient, f, and wear depth, h, increase linearly with Kmax . The maximum gradient Kmax, which can be measured using a simple technique, is a potential indicator to preliminarily evaluate the wear state of ferromagnetic materials during frictional wear [ABSTRACT FROM AUTHOR]

This paper describes a novel promising film based on the flowerlike CuWO4 structure, and applied to photoelectrochemical (PEC) water splitting as a photoanode first. The growth mechanism and microstructure of CuWO4 are discussed in detail. The PEC measurements indicate that flowerlike CuWO4 exhibited a photocurrent density of 0.58 mA/cm² at 0.8 V versus RHE. When coupled with CdS and FeOOH layers, the triple CuWO4/CdS/FeOOH photoanode exhibited further improved PEC performance with a higher photocurrent density of about 2.05 mA/cm² at 0.8 V versus RHE and excellent operation stability. The remarkable PEC performance stems from several crucial factors: (i) ideal band gap; (ii) improved light absorption; (iii) efficient charge-hole pair separation and collection. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the anti-exudative effects of sodium ferulate combined with oxymatrine in a mouse model of acetic acid-induced peritonitis. Furthermore, the underlying mechanisms were explored by determining the effects of these drugs on the volume and aquaporin 1 (AQP1) expression in vascular endothelial cells on omentum majus and human umbilical vein endothelial cells (HUVEC). Treatment with sodium ferulate combined with oxymatrine was shown to significantly inhibit acetic acid-induced vascular permeability in the peritonitis model mice and furthermore to significantly decrease the optical density of Evans blue, the leukocyte number and the levels of interleukin-6, C-reactive protein and interferon-γ in peritoneal lavage fluid. Pathological analysis of the omentum majus revealed that sodium ferulate and oxymatrine combination treatment significantly alleviated vascular endothelial cell edema and capillary loss. In vitro, flow cytometry revealed that the volume of HUVECs was significantly reduced in the drug treatment groups, as reflected in the forward scatter value. The optical density of AQP1 on the membrane of the vascular endothelial cells on omentum majus and HUVECs were significantly increased in the drug treatment groups compared with the model group. These results indicated that sodium ferulate and oxymatrine combination treatment possessed prominent anti-exudative effects and that the underlying mechanisms are likely to include the improvement of vascular endothelial cellular edema, possibly by upregulation of AQP1 expression on their membrane, which requires further exploration. [ABSTRACT FROM AUTHOR]

Tetrabenzo[7]circulene, a new member of aromatic saddles, was conveniently synthesized from 2-(1-naphthoyl)benzoic acid with the seven-membered ring constructed at an early stage of the synthesis. This method, upon minor modification, was also useful for synthesis of thiophene-annulated [7]circulenes. The structures of tetrabenzo[7]circulene and [7]circulene were compared in terms of symmetry, flexibility, and curvature on the basis of DFT calculations and X-ray crystallography. It was also found that tetrabenzo[7]circulene functioned as a p-type semiconductor in thin-film transistors and cocrystallized with C60. [ABSTRACT FROM AUTHOR]

It is critical to study the mass transfer of supercritical fluid degradation for carbon fiber composites to investigate their degradation mechanism, design the reactor, and develop recycling processes. The mass transfer process of supercritical fluid degradation was described from two aspects: mass diffusion from outside to inside, and from inside to outside. Mass transfer model of supercritical fluid degradation was established based on a proposed concentric cylindrical representative volume element. The reaction kinetic parameters were incorporated into the mass transfer equation, and the concentration distribution of supercritical fluid, mass transfer rate, reaction order, and reaction rate constant during the carbon fiber composites degradation process were calculated. Relaxation time was incorporated into the mass transfer process, and the supercritical fluid concentration calculation method considering non-Fick effect was proposed. Finally, two pretreatment methods were adopted to speed up the mass transfer process. [ABSTRACT FROM AUTHOR]

The lubricant film of hydrostatic circular pad in the heavy-duty rotary table is affected by the roughness, thermal and hydrodynamic effect, which can cut down the load‑carrying capacity and machining accuracy of the heavy-duty machine tool. In this paper, a coupled energy equation with mean Reynolds equation based on the Christensen’s stochastic model of rough surfaces is presented to analyze the temperature rising, pressure distribution and load‑carrying capacity of the hydrostatic circular pad. The mean Reynolds equation, momentum equation, continuity equation, and energy equation are coupled and solved using the finite difference method to obtain the characteristics of lubricant film. It is found that the uneven pressure distribution and the temperature rising of lubricant film in resistive oil edge of hydrostatic circular pad are related to the increase of dimensionless hydrodynamic parameter S due to the thermal and hydrodynamic coupling effect. The load-carrying capacity and stability of heavy-duty rotary table is weakened due to the thermal and hydrodynamic effects. [ABSTRACT FROM AUTHOR]

The energy efficiency of the piston pumps is one of the considerable important factors in design and analysis of hydraulic system, especially in the process of real-time tracking of energy dissipation in a variety of loading conditions. The existing methods for obtaining the energy efficiency curve of piston pumps are either time-consuming or inaccurate. In order to quantify the energy efficiency of the piston pumps quickly and accurately, the leakage and friction energy loss caused by the clearances in the sliding pairs are analyzed, and an overall efficiency model was established, which contains two constants to be determined by two test points. The accuracy of the model was verified based on a test rig for a hydraulic pump, and it can be improved by selecting appropriate test points via the method of deviation analysis. The results show that the proposed efficiency models are in good agreement with the experimental results, and the best test points are in the range of 0–25% and 51–75% of the peak pressure of the investigated piston pump. [ABSTRACT FROM AUTHOR]

Trichohepatoenteric syndrome (THES) is a rare autosomal, recessively inherited disorder. Mutations in the tetratricopeptide repeat domain 37 (TTC37) gene and the superkiller viralicidic activity 2-like (SKIV2L) gene have been identified to cause THES. The present study reported a case of a Chinese boy, who presented clinically with intrauterine growth retardation, intractable diarrhea, facial dysmorphism, abnormal scalp hair shafts, immune disorders and liver involvement. Targeted next-generation sequencing and Sanger DNA sequencing showed compound heterozygous mutations of the SKIV2L gene. The present study was the first, to the best of our knowledge, to report a case of a boy with THES resulting from compound heterozygous mutations of the SKIV2L gene in China. Target sequence capture combined with high-throughput next-generation sequencing technologies have shown to be effective methods for the molecular genetic assessment of rare inherited disorders. [ABSTRACT FROM AUTHOR]

We herein report an efficient synthesis of dibenzo[rt,m]rubicene, a new member of nonplanar cyclopenta-fused polycyclic aromatic hydrocarbon, and its derivatives. It is found th a t the conformation and molecular packing of dibenzo[a,m]rubicenes in the solid state can be tuned by the substituting groups, and the silylethynylated derivatives of dibenzo[fl,m]rubicenes function as p-type organic semiconductors in solution-processed thin film transistors with field effect mobility of up to 1.0 cm2 V–1 s–1. [ABSTRACT FROM AUTHOR]

Experimental evidence suggested that sodium ferulate (SF) and oxymatrine (OMT) combination had synergistic anti-inflammatory and antioxidant effects. We hypothesized that SF and OMT combination treatment might have protective effects on paraquat-induced acute lung injury. In our study, the Swiss mice were randomly divided into seven groups, including control, paraquat (PQ), SF (6.2 mg/Kg/day); OMT (13.8 mg/Kg/day) and three SF+OMT groups (3.1 + 6.9; 6.2 + 13.8 and 12.3 + 27.7 mg/Kg/day). The mortality and death time were monitored. Sprague-Dawley rats were randomly divided into seven groups including control, PQ, SF (3.1 mg/Kg/day); OMT (6.9 mg/Kg/day) and three SF+OMT groups (1.6 + 3.4; 3.1 + 6.9 and 6.2 + 13.8 mg/Kg/day). The lung wet/dry weight (W/D) ratio, lung histopathologic changes, C-reactive protein (CRP), interleukin-6 (IL-6), nuclear factor κB (NF-κB), malondialdehyde (MDA) and superoxidase dismutase (SOD) were analysed. Compared with PQ group, the mortality significantly decreased and the death time prolonged in SF and OMT combination treatment groups of mice. Also in SF and OMT combination treatment groups of rats, the increased lung W/D ratio and histopathological score induced by PQ injection were significantly decreased; the levels of CRP, IL-6, NF-κB and MDA in serum and lung homogenate were significantly decreased; the SOD activities in serum and lung homogenate were improved. These results suggested that SF and OMT combination had an obvious protective effect on PQ-induced lung injury. The anti-inflammatory and antioxidant effect might be involved in the mechanism. [ABSTRACT FROM AUTHOR]

Curcumin is known to possess anti-inflammatory properties. Despite the fact that curcumin is known to be a strong inhibitor of H+, K+-ATPase activity, the mechanism underlying the curcumin-induced inhibition of the transcription of the H+, K+-ATPase α subunit in gastric mucosal parietal cells remains unclear. The present study investigated the possible mechanism by which curcumin inhibits stomach H+, K+-ATPase activity during the acute phase of gastric ulcer disease. A rat model of stress-induced gastric ulcers was produced, in which the anti-ulcer effects of curcumin were examined. Curcumin-induced inhibition of the H+, K+-ATPase promoter via histone acetylation, was verified using a chromatin immunoprecipitation assay. The results showed that curcumin improved stress-induced gastric ulcer disease in rats, as demonstrated by increased pH values and reduced gastric mucosal hemorrhage and ulcer index. These effects were accompanied by a significant reduction in the level of histone H3 acetylation at the site of the H+, K+-ATPase promoter and in the expression of the gastric H+,K+-ATPase α subunit gene and protein. In conclusion, curcumin downregulated the acetylation of histone H3 at the site of the H+, K+-ATPase promoter gene, thereby inhibiting the transcription and expression of the H+, K+-ATPase gene. Curcumin was shown to have a preventive and therapeutic effect in gastric ulcer disease. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effects of the combination of sodium ferulate (SF) and oxymatrine (OMT) on mice with cecal ligation and puncture (CLP) -induced sepsis. Swiss male mice were randomly divided into a control group, CLP group, three SF + OMT groups (3.1+6.9; 6.2+13.8 and 12.3+27.7 mg/kg), SF (6.2 mg/kg) group and OMT (13.8 mg/kg) group. Eight hours after the administration of the drugs, the survival rates and survival times of the animals were monitored. In addition, the lung wet/dry weight (W/D) ratio; alanine aminotransferase (ALT), aspartate aminotrans-ferase (AST) and lactate dehydrogenase (LDH) levels in the serum; the C-reactive protein (CRP), interleukin-6 (IL-6) and interferon-γ (IFN-γ) levels in the serum and lung and liver homogenates; and the malondialdehyde (MDA) and superoxi-dase dismutase (SOD) levels in the lung and liver homogenates were measured. The bacterial load in the serum was also studied. Following treatment with the combination of SF and OMT, the survival rate increased and the survival time was prolonged; CLP-induced increases in the lung W/D ratio and the levels of ALT, AST, LDH, CRP, IL-6, IFN-γ and MDA were significantly reduced; and the SOD activity levels were increased, compared with those of the untreated animals with CLP-induced sepsis. These results indicated that the combination of SF and OMT induced protective effects against CLP-induced lethal sepsis of mice. The possible mechanism of these effects may be associated with the alleviation of systemic inflammation and diminishment of oxidative injury. [ABSTRACT FROM AUTHOR]

The motivation of this paper is to develop a new and straightforward approach to provide a topology optimization solution for the layout design of stiffened plate/shell structures. Inspired by the similarities between the branching patterns in nature and stiffener layout patterns in engineering, a so-called material increasing design concept is first introduced to represent the topology configuration of the stiffened plate/shell structures. In addition, a well-founded mathematical explanation for the principles, properties, and mechanisms of adaptive growth behaviors of branching patterns in nature is derived from the Kuhn-Tucker conditions, leading to a novel optimality criterion which can serve engineering purposes for stiffener layout design. In this criterion, the common growth mechanism is described as an ideal 'balanced point' among individual branches in terms of their weight distribution. After characterizing the relationship between the growth behavior and mechanics self-adaptability, the reproduction of branching patterns in nature is implemented by a global coordinative model, which consists of several bottom programming models to find the optimal height distributions of individual branches and a top programming model to play a global coordinative role among them. The benefit and the advantages of the suggested method are illustrated with several 2D examples that are widely used in the recent research of topology optimization. [ABSTRACT FROM AUTHOR]

Biological structures with preeminent performance in nature endow inexhaustible inspiration for creative design in engineering. In this paper, based on the observation of the naturalmorphogenesis of leaf veins, we put forward a simple and practicalmultidiscipline topology optimization method to produce the stiffener layout for plate/shell structures. This method simulates the emergence of complex branching patterns copying the self-optimization of leaf veins which always try to grow into a configuration with global optimal performances. Unlike the conventional topology optimizationmethods characterized by "subtractionmode," the proposed method is based on the "addition mode," giving great potential for designers to achieve more clear stiffener layout patterns rather than vague material distributions and, consequently, saving computational resources as well as enhancing availability of design outputs. Numerical studies of both static and dynamic problems considered in this paper clearly showthe suitability of the proposed method for the optimal design of stiffened plate/shell structures. [ABSTRACT FROM AUTHOR]

The transfer of ligninolytic enzymes in composting substrates (soil, vegetable leaf, rice straw and chaff) was investigated using a series of column elution experiments. Environmental scanning electron microscope (ESEM) and Fourier transform infra-red spectroscopy (FTIR) were used to analyze the mechanism of ligninolytic enzymes adsorption onto those substrates. The significant differences were found between substrates with adsorption of enzymes and those without enzymes by FTIR. Hydrophobic groups (methylene and alkane groups) and active groups (—CH2— CO—or— CH2— NH— ) contents decreased in the substrates with adsorption of enzymes. The transfer abilities of total protein in the four composting substrates (soil, vegetable leaf, rice straw and chaff) were weakened as the ratio of manganese peroxidase (MnP) to lignin peroxidase (LiP) increased from 4 to 6, and were enhanced when the MnP/LiP ratio increased to 8. The transfer abilities of LiP in the four composting substrates were enhanced continually with the increasing MnP/LiP ratio. The transfer of MnP was similar to that of total protein with the change of MnP/LiP ratio. These results indicated that the change of MnP/LiP ratio could affect the transfer of ligninolytic enzymes in different composting substrates. [Copyright &y& Elsevier]