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Literature notes that firms are keen to develop big data analytics capability (BDAC, e.g. big data analytics (BDA) management and technology capability) to improve their competitive performance (e.g. financial performance and growth performance). Unfortunately, the extant literature has limited understanding of the mechanisms by which firms' BDAC affects their competitive performance, especially in the context of small and medium-sized enterprises (SMEs). Using resource capability as the theoretical lens, this paper specifically examines how BDAC influences SMEs' competitive performance via the mediating role of business models (BMs). Also, this study explores the moderating effect of COVID-19 on the relationship between BDAC and BMs. Supported by Partial Least Squares-Structural Equation Modelling (PLS-SEM) and data from 242 SMEs in China, this study finds the mediating roles of infrastructure and value attributes of BMs in enhancing the relationship of BDAC on competitive performance. Furthermore, the improvement of financial performance comes from the matching of BDA management capability with infrastructure attributes of BMs, while the improvements in growth come from the matching of BDA management capability and BDA technology capability with value attributes of BMs. The result also confirms the positive moderating effects of COVID-19 on the relationship of BDA management capability and value attributes of BMs. This study enriches the integration of BDAC and BMs literature by showing that the match between BDAC and BMs is vital to achieve competitive performance, and it is helpful for managers to adopt an informed BDA strategy to promote widespread use of BDAs and BMs.

Microvascular invasion (MVI) is a key pathological factor that severely affects the postoperative prognosis of patients with hepatocellular carcinoma (HCC). However, no MVI classification schemes based on standardized gross sampling protocols of HCC are available at present. 119 HCC specimens were sampled at multiple sites (3-, 7-, and 13 points) for the optimum MVI detection rate. 16,144 resected HCCs were graded as M0, M1 or M2 by adopting three-tiered MVI grading (MVI-TTG) scheme based on the seven-point sampling protocol (SPSP). Survival analyses were performed on 2573 patients to explore the advantages of MVI-TTG. The MVI detection rate determined by SPSP was significantly higher than that determined by the 3-point sampling method (34.5% vs. 47.1%, p = 0.048), but was similar to that determined by the 13-point sampling method (47.1% vs. 51.3%, p = 0.517). Among 16,144 resected HCCs, the proportions of M0, M1 and M2 specimens according to SPSP were 53.4%, 26.2% and 20.4%, respectively. Postoperative survival analysis in 2573 HCC patients showed that the 3-year recurrence rates in M0, M1 and M2 MVI groups were 62.5%, 71.6% and 86.1%, respectively (p

Erosion control materials with long-term effective, economical and environmentally friendly properties play a critical role in controlling erodible and unstable sandy slopes deformed under rainfall. In this study, a novel cellulose-based curing agent was developed and applied as a sustainable sand fixation materisal. The novel cellulose-based curing agent was a dual-polymer composite material (DPCM), which was prepared by mixing two kinds of organic polymer materials: carboxymethyl cellulose (CMC) and polyacrylamide (PAM). The microstructure and composition of DPCM were characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The adsorption kinetics of the curing agent on sand particles was discussed by fitting with pseudo-first-order and pseudo-second-order kinetic models. Water resistance and the compressive strength of the sand-fixing specimen at different curing ages were studied. Finally, the DPCM stabilization layer’s resistance to water erosion was investigated using a rainfall simulation test. The results demonstrated that the adsorption kinetic behavior of DPCM adsorbed on sand particles followed pseudo-second-order kinetics. Additionally, the interaction between the DPCM and sand particles was primarily hydrogen bonding, covalent bonds, and physical adsorption. The compressive stress was in the range from 53 to 915 kPa. Sandy slopes treated by DPCM showed excellent resistance to water erosion under a rainfall intensity of 120 mm/h.

For electrically conductive adhesives (ECAs), high electrical conductivity generally conflicts with excellent mechanical properties because electrical conductivity increases while desirable mechanical properties decrease with the increase in loading of conductive fillers or removal of lubricants on the silver filler surface. In this work, a method was developed to improve both the electrical conductivity and mechanical properties of the ECAs by introducing double bonds. Itaconic acid (IA) was used to replace the lubricant on the silver flake (Ag-F) surface, and acrylic acid (AA) was used as part of the ECA resin matrix. IA can replace the lubricant on the Ag-F surface, similar to other short-chain dibasic acids, to improve the ECA electrical conductivity. Furthermore, IA can be polymerized with AA to form covalent bonds between the silver flakes and the resin matrix, enhancing the mechanical properties of ECA. Compared with ECA filled with commercial silver flakes, the electrical conductivity of ECA filled with IA-treated silver flakes increased by ~ 21%, and the lap shear strength increased by ~ 29%.

We aimed to establish a discriminative gene-expression-based classifier to predict survival outcomes of T-cell lymphoblastic lymphoma (T-LBL) patients. After exploring global gene-expression profiles of progressive (n = 22) vs. progression-free (n = 28) T-LBL patients, 43 differentially expressed mRNAs were identified. Then an eleven-gene-based classifier was established using LASSO Cox regression based on NanoString quantification. In the training cohort (n = 169), high-risk patients stratified using the classifier had significantly lower progression-free survival (PFS: hazards ratio 4.123, 95% CI 2.565–6.628; p

Catalytic oxidation of formaldehyde (HCHO) at ambient temperature is an effective method for indoor HCHO removal. In this study, Ni/Co-Layered double hydroxides (LDHs) with different molar ratios were successfully synthesized via a one-step hydrothermal method. Their structure and morphology were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET)-specific surface area, X-ray photoelectron spectroscopy (XPS), and H2 temperature-programmed reduction (H2-TPR), respectively. The catalytic activity results show that Ni/Co-LDHs with the Ni/Co ratio of 1:2 exhibited enhanced activity for HCHO decomposition. The removal efficiency of indoor HCHO was up to 99.7% at ambient temperature, and it remained highly stable without any obvious deactivation even after a reaction time of 800 min. The abundant hydroxyl groups were favorable for catalytic activity, which could not only enrich the adsorption of HCHO on the surface of catalysts, but also directly react with HCHO to obtain CO2 and H2O. Moreover, the redox cycles of Ni3+/Ni2+ and Co3+/Co2+ would provide more reactive oxygen species and therefore promote catalytic reaction. This work can provide a new insight into LDH-based catalysts for low-concentration HCHO removal in practical application.

The issue, high glass-forming abilities (GFAs) in solute-absent multicomponent metallic glasses (MGs), has been investigated by systematic experimental measurements coupled with theoretical calculations in the Cu34Zr14Ti36Pd16 quaternary alloy. It is found that the synergetic contribution of some atomic- and cluster-level structural features leads to the high GFA in this quaternary composition. At the atomic scale, Pd and Ti addition decreases the size gaps between Cu and Zr atoms, and increases the atomic packing efficiency; at the cluster scale, there are more icosahedral or icosahedral-like local structures, and the cluster regularity is enhanced because of the optimization of both topological and chemical distributions in clusters. The present work provides an in-depth understanding of GFAs in multicomponent alloys, and will shed light on the development of more MGs with high GFAs.

Intraductal papillary neoplasms of the bile duct (IPNBs) are a group of rare lesions with uncertain clinical findings and imaging features. We aim to investigate the clinicopathological features and imaging findings of IPNBs on contrast-enhanced ultrasound (CEUS) and contrast-enhanced computed tomography (CECT). From February 2005 to March 2018, 30 patients with pathologically confirmed IPNBs were retrospectively identified in our hospital. Demographic, clinical, and pathological data, CEUS and CECT features and surgical strategies were analyzed. The most common clinical manifestations were abdominal pain (53.3%), jaundice (23.3%), and acute cholangitis (10.0%). Among all lesions, 5/30 (16.7%) lesions presented as dilated bile ducts only, while 13/30 (43.3%) lesions presented as dilated bile ducts with intraductal papillary masses, and 12/30 (40.0%) presented as solid masses with dilated bile ducts. For the 20 patients who underwent both CEUS and CECT, 18 lesions were hyperenhanced on CEUS, and 17 lesions were hyperenhanced on CECT in the arterial phase. In total, 16 and 18 lesions showed washout in the portal and late phases on CEUS, while the corresponding number of lesions that showed washout in the portal and late phases on CECT were 11 and 13. Twelve lesions (40.0%) showed atypical hyperplasia, while 16/30 (53.3%) lesions underwent malignant transformations. There are 3 major forms of IPNBs on grayscale ultrasound, including diffusely dilated bile ducts without visible mass; focal dilated bile duct with intraductal papillary masses; and solid mass surrounded by dilated bile ducts. The enhancement patterns of IPNBs on CEUS and on CECT were consistent. IPNB has a high malignant potential, and patients should be treated with surgical resection after the diagnosis is established.

New prognostic factors are needed to establish indications for haematopoietic stem cell transplantation (HSCT) in first complete remission (CR1) for T-cell lymphoblastic lymphoma (T-LBL) patients. We used microarray to compare T-LBL tissue samples (n = 75) and fetal thymus tissues (n = 20), and identified 35 differentially expressed miRNAs. Using 107 subjects as the training group, we developed a five-miRNA-based classifier to predict patient survival with LASSO Cox regression: lower risk was associated with better prognosis (disease-free survival (DFS): hazard ratio (HR) 4.548, 95% CI 2.433–8.499, p

Higher mortality in asthmatics has been shown previously. However, evidence on different asthma phenotypes on long-term mortality risk is limited. The aim was to evaluate the impact of asthma phenotypes on mortality in general population. Data from the National Health and Nutrition Examination Survey from 2001–2002 to 2013–2014 linked mortality files through December 31, 2015, were used (N = 37,015). Cox proportional hazards regression was used to estimate the risk of all-cause and cause-specific mortality adjusting for sociodemographic characteristics, smoking, body mass index, and chronic conditions. During the mean follow-up time of 7.5 years, 4326 participants died from a variety of causes. Current asthma, but not former asthma was associated with increased all-cause mortality (current asthma: HR = 1.37; 95% CI 1.20–1.58; Former asthma: HR = 0.93; 95% CI 0.73–1.18); as well as mortality from cardiovascular disease (HRCurrent = 1.41; 95% CI 1.08–1.85) and chronic lower respiratory diseases (HRCurrent = 3.17; 95% CI 1.96–5.14). In addition, we found that the HR for cardiovascular disease (CVD) mortality was slightly greater in people with childhood-onset asthma than those with adult-onset asthma. The HR for chronic lower respiratory diseases (CLRD) mortality was greater in people with adult-onset asthma than those with childhood-onset asthma. However, the differences were not statistically significant. Our study suggested that current asthma but not former asthma was associated with increased all-cause, CLRD and CVD mortality. Future well-designed studies with larger sample are required to demonstrate the association and clarify the potential mechanisms involved.

Preoperative prediction of microvascular invasion (MVI) in patients with hepatocellular cancer (HCC) is important for surgery strategy making. We aimed to develop and validate a combined intratumoural and peritumoural radiomics model based on gadolinium-ethoxybenzyl-diethylenetriamine (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) for preoperative prediction of MVI in primary HCC patients. This study included a training cohort of 110 HCC patients and a validating cohort of 50 HCC patients. All the patients underwent preoperative Gd-EOB-DTPA-enhanced MRI examination and curative hepatectomy. The volumes of interest (VOIs) around the hepatic lesions including intratumoural and peritumoural regions were manually delineated in the hepatobiliary phase of MRI images, from which quantitative features were extracted and analysed. In the training cohort, machine-learning method was applied for dimensionality reduction and selection of the extracted features. The proportion of MVI-positive patients was 38.2% and 40.0% in the training and validation cohort, respectively. Supervised machine learning selected ten features to establish a predictive model for MVI. The area under the receiver operating characteristic curve (AUC), sensitivity, specificity of the combined intratumoural and peritumoural radiomics model in the training and validation cohort were 0.85 (95% confidence interval (CI), 0.77–0.93), 88.2%, 76.2%, and 0.83 (95% CI, 0.71–0.95), 90.0%, 75.0%, respectively. We evaluate quantitative Gd-EOB-DTPA-enhanced MRI image features of both intratumoural and peritumoural regions and provide an effective radiomics-based model for the prediction of MVI in HCC patients, and may therefore help clinicians make precise decisions regarding treatment before the surgery. • An effective radiomics model for prediction of microvascular invasion in HCC patients is established. • The radiomics model is superior to the radiologist in prediction of MVI. • The radiomics model can help clinicians in pretreatment decision making.

Synthesis, characterization, and coating performance of castor oil (CO)-based waterborne hyperbranched polyurethane acrylate (WHPUA) emulsions are highlighted in this work. Herein, a second-generation CO-based hyperbranched polyester (C20) was synthesized by introducing the renewable CO as a B3 core and dimethylolpropionic acid as an AB2 monomer via a pseudo-one-pot condensation procedure. Three types of CO-based WHPUA emulsions were prepared through the addition of the hyperbranched C20 with maleic anhydride (MA) and the isocyanate-bearing semiadduct (IPDI-HEA) at different MA/IPDI-IH molar ratios without the addition of any emulsifiers. The prepared emulsions were further formulated into UV-curable coating formulations and exposed to a medium-pressure mercury lamp. Consequently, the obtained UV-cured coatings exhibited outstanding adhesion performance, excellent transparency, and an acceptable degree of final double bond conversion. Owing to a relatively low concentration of hydrophilic units and a large number of acrylate functionalities in the waterborne oligomer, the obtained films were endowed with high crosslinking density and low hydrophilic nature, thus producing enhanced tensile strength, pencil hardness, water resistance, and chemical resistance. Due to their combination of renewable materials, a waterborne system and a UV-curing technique, these CO-based WHPUA emulsions offer promising opportunities to be used as environmentally friendly coatings.

A novel environmentally friendly method was developed to fabricate hollow core–shell conductive nanoparticles using a natural and nontoxic material, nanocrystalline cellulose (NCC), as the template. The NCC used in this study has nano-scale rod-like structure. After the oxidization to dialdehyde cellulose, the insulated NCC was functionalized by poly(dopamine) (PDA) in weakly alkaline conditions through Schiff base reaction and self-polymerization. The Schiff base can be hydrolyzed in an aqueous acetone solution via ultraviolet radiation so that the hollow structure constructed. This structure not only strengthened the mechanical properties but also provided more active sites for silver deposition. Utilizing the chelating ability of the catechol groups in PDA, electroless plating method was used to form the silver coating layer. Scanning electron microscope and Dynamic Light Scattering measurements indicated that these nanoparticles (NPs) had well-defined morphology and a mean diameter of 100–120 nm. Moreover, these prepared Ag–DA–NCC0 NPs exhibited excellent conductivity. Their electrical resistivity reached 0.2 mΩ·cm, which is much higher than that of many other conductive particles used in conductive adhesive.

This paper reports on a novel self-matte or bulk-matte waterborne polyurethane coating composite with inherently extremely low gloss. The coating composite was comprised of a siloxane-containing waterborne polyurethane (SPU) resin and a crosslinked waterborne polyurethane (CPU) resin. The CPU resin was mainly responsible for fabricating the micro-rough surface of the film, which was achieved by a crosslinking reaction between the waterborne polyurethane and bisphenol A-type epoxy E-44 resin. The SPU resin was used to improve the comprehensive properties of the film, which was ascribed to the addition of silane coupling agent KH792. Compared with traditional matte coatings, this coating composite made it possible to avoid high loadings of matting agent and to arrive at highly flexible low-gloss finishes. Gloss levels of as low as a few tenths of a percent, even at high incidence angles, have been achieved with zero loading of extraneous dulling agent. The chemical structures of the SPU and CPU resins were characterized by FTIR-ATR and NMR spectra. The micro-rough topographies and surface rough degrees of the SPU, CPU and their 50%/50% composite films were measured by SEM and MSP, respectively. The particle sizes and particle morphologies of the SPU and CPU resins were imaged by TEM. Finally, the comprehensive properties of the SPU, CPU and their 50%/50% composite resins were evaluated, including the water contact angle, film transparency, tensile strength and storage stability.

Manganese dithionate (MnS2O6), formed in the leaching process of pyrolusite slurry with SO2, is a concern because of its ability to decrease the purity of MnSO4 (industrial raw material). Information regarding the oxidation and recovery of dithionate ion is scarce. In this study, we investigated the leaching process of MnO2 with MnS2O6 in the liquid phase. The leaching reaction presented one way to oxidize MnS2O6. The most suitable operating parameters on the oxidation efficiencies of MnS2O6 were established as follows: MnO2 dosage, 21.7 g L−1; agitation speed, 450 rpm; initial H2SO4 concentration, 1.81 mol L−1; initial MnS2O6 concentration, 28.5 g L−1; and reaction temperature, 372.5 K. Under the optimum conditions, the removal efficiency of 97.55% for MnS2O6 was obtained in 30 min. The experimental results showed that increasing the initial concentrations of MnS2O6 and H2SO4 and the reaction temperature resulted in a decrease in the content of MnS2O6. The dithionate oxidation process could be well modeled by the shrinking core model with an inert product layer, which indicated that the process was controlled by the interfacial chemical reaction. The reaction orders with respect to initial H2SO4 concentration and initial MnS2O6 concentration were 1.64 and 0.18, and the activation energy was 60.1 kJ mol−1 as well as pre-exponential factor was 5.9 × 106.

Self-matt coating of waterborne polyurethane (WBPU) was synthesized by combining prepolymer and self-emulsification methods. The emulsion was fabricated from both hydroxy carboxylic acid and aminosulfonic acid types of hydrophilic chain-extending agents, in which the 2-[(2-aminoethyl) amino] ethane sulphonate sodium (AAS salt) was produced in laboratory. This emulsion demonstrated an excellent matt performance without the addition of extra matting agents after filming. Four different kinds of surface properties were measured on the film: the specular gloss (60° gloss meter), the contact angle (CA), the surface roughness degree (3D Surface Profilometer), and the topography of the coatings surface (SEM). The results showed that tons of spherical particles with diameter in a few micrometers were aggregated on the film surface. The effect of the roughness parameters (R a and R q ) and the average particle size of the emulsions on the specular gloss degree were probed. The research indicated that the emulsion with average particle size in the range of 2.5–3.0 µm and, meanwhile, the film with roughness parameters R a and R q both greater than 1 µm could attain the best matt effect. The WBPU emulsions showed good physical and mechanical properties, and were introduced into wood varnish for matting purpose.

To prospectively investigate the usefulness of acoustic structure quantification (ASQ) for noninvasive assessment of liver fibrosis in patients with chronic hepatitis B (CHB). Consecutive patients with CHB scheduled for liver biopsy or partial liver resection underwent standardized ASQ examinations. The ASQ parameter, named focal disturbance (FD) ratio, were compared with METAVIR scores. The analysis was based on receiver operating characteristic (ROC) curves and multiple regression analysis. A total of 114 patients were enrolled in the final analysis. The area under the ROC curve for the FD ratio was 0.84 for significant fibrosis (≥ F2), 0.86 for severe fibrosis (≥ F3), and 0.83 for cirrhosis (= F4). The optimal cutoff values for the FD ratio were 0.25, 0.30 and 0.50 for fibrosis stages ≥ F2, ≥ F3 and = F4, respectively. The prevalence of a difference of at least two stages between the FD ratio and the histological stage was 12.3 % (14 of 114). The fibrosis stage (P

Allograft rejection has been an obstacle for long-term survival of patients for many years. Current strategies for transplant rejection are not as optimal as we expected, especially for long-term treatments. Trichinella spiralis, a nematode parasitized in mammalian muscle and as an invader, maintains harmonious with host in the long term by evading host immune attack. To determine whether T. spiralis infection impacts on allograft rejection, we performed mice cardiac allograft transplantation model by using BALB/c (H-2(b)) mice as donors and C57BL/6 (H-2(b)) mice orally infected with 300 muscle larvae for 28 days as recipients. Graft survival was monitored by daily palpation of the abdomen; histologic change was observed by HE stain; and CD4(+), CD8(+), CD4(+)IFN-γ(+), and CD4(+)IL-17(+) T cells and regulatory T cells were examined with the use of flow cytometry. Serum cytokine levels were measured by Luminex. Finally, we found that mean survival time of cardiac allografts in T. spiralis group was 23.40 ± 1.99 days, while the vehicle control group was 10.60 ± 0.75 days. Furthermore, we observed alleviated histological changes in the heart allograft, decreased corresponding CD8(+) T cells, suppressed Th1 and Th17 responses, and increased regulatory T cell frequency in a murine cardiac transplantation model at day 7 post-transplantation in experimental group. These data suggest that T. spiralis infection resulted in prolonged allograft survival following murine cardiac transplantation, with suppressed Th1/Th17 responses and augmented regulatory T cells.

Single-crystal X-ray diffraction structural data of four Fe-Mg tourmalines with different Fe contents from Xinjiang, Sichuan, and Yunnan Provinces, China, were collected at room temperature and −100°C. The intrinsic dipole moments of polyhedra and the total intrinsic dipole moment of the unit cell were calculated. By comparing the intrinsic electric dipole moments of the X, Y, Z, T, and B site polyhedra, it is found that the T site polyhedron makes the greatest contribution to the total intrinsic dipole moment. The pyroelectric coefficients of four Fe-Mg tourmalines were experimentally determined, and the influence of intrinsic dipole moments on their pyroelectric properties was investigated. The experimental results show that, compared with the case at room temperature, the intrinsic dipole moments change with the total Fe content at −100°C in a completely different way. With the decrease of temperature, the total intrinsic dipole moments of tourmaline decrease. Over the same temperature interval, the pyroelectric coefficients increase with the increase in intrinsic dipole moment.

Polyurethane foam (PUF) was prepared from liquefied wood with polymethylene polyphenylisocyanate by one-shot method, with organosilicon as surfactant, water as blowing agent and stannous octoate and triethylene diamine as co-catalyst. The biodegradability of the PUF was studied by soil burial for a period of 12 months. The Fourier transform infrared (FT-IR) study, morphological observation and percent weight loss were used to discuss the biodegradability of polyurethane foam from liquefied wood. The FT-IR analyses showed that the PUF had biodegraded via oxidation of the ether soft segment or degradation of wood components. The weight loss rate showed that the addition of liquefied wood could accelerate the degradation of PUF.

Semi-interpenetrating network(semi-IPN) hydrogels composed of sodium carboxylmethyl cellulose(NaCMC) and poly N-isopropylacrylamide(PNIPAm) were prepared by free radical polymerization of N-isopropyl acrylamide(NIPAm) in dimethylsulfoxide(DMSO) in the presence of NaCMC. The structures of hydrogels were characterized by Fourier transform infrared spectroscopy(FTIR), scanning electron microscopy(SEM) and differential scanning calorimetry(DSC). SEM images show that the hydrogels present porous network structures. Most water in the hydrogels were free water and freezing water. The equilibrium swelling ratio(ESR) and swelling rate(SR) were quite different at various swelling temperature. ESR of the hydrogels ranged abruptly from 15.2 g/g to 1.56 g/g and the hydrogels changed from transparent into opaque with swelling temperature changing from 33 °C to 34 °C, that is to say, the hydrogels exhibited the good temperature sensitivity at about 33 °C similar to low critical solution temperature(LCST) of pure PNIPAm, swelling rate were very different at below and above LCST due to hydrogel swelling with different swelling mechanism. Moreover, the semi-IPN hydrogels swelled much rapidly than pure PNIPAm hydrogels did at room temperature, the equillibrium swelling ratio(ESR) and swelling rate of the hydrogels increased with increasing of NaCMC content, i e. It is suggested that NaCMC could be potential for preparation of porous and rapid swelling hydrogels

Effects of three dispersed medium systems consisting of isopropyl alcohol (IPA), ethyl alcohol (EtOH) and toluene (TOL) on the substitution patterns of carboxymethyl cellulose (CMC) were studied, and the corresponding influences on solution performances were investigated on a rheometer. In EtOH-IPA system, the structure of higher average substitution degree and enlarged partial substitution degrees disparity (determined by 1H nuclear magnetic resonance) but lower distribution uniformity along molecular chains (speculated from static/dynamic light scattering) were characterized by which the thixotropy and apparent viscosity of solution decreased due to the aggregation of longer unsubstituted segments. For the phase separation (identified by gas chromatography) of TOL-IPA system, considerable unsubstituted regions in the structure aggregated into hydrophobic centers to form swollen macrogel particles in solution, leading to the sharp rise in apparent viscosity and almost constant flow-behavior index with hardly any thixotropic behaviors presented.

Nonwoven fiber mats of hydroxypropyl methylcellulose trimellitate (HPMCT) with potential applications in controlled delivery of drugs and scaffolds for tissue cultures have been successfully fabricated by electrospinning of HPMCT solutions. The formation and diameters of HPMCT fibers fabricated by electrospinning were strongly influenced by the solvents employed, electrostatic field strength, and solution concentrations. The electrospun products generated from all HPMCT solutions with various weight-average molecular weights in methanol/dichloromethane (1:1) solvent consisted of clustered beads, while methanol/dichloromethane (1:5) solvent helped to generate smooth, uniform, submicron fibers. From the relationship between specific viscosity and molecular weight in different solvents, it could be concluded that methanol/dichloromethane (1:5) solvent enhanced the molecular entanglements, improved the viscosity of the solutions, thus helped to generate smooth fibers. When all the other variables were kept constant, the concentration range suitable for electrospinning was between 10% and 16% (wt), and the average fiber diameter increased as the concentration increased. When all the other variables were kept constant, the average fiber diameter decreased as the strength of the electrostatic field increased. Electrospinning the solutions of two compounds with similar structure, hydroxypropyl methylcellulose phthalate (HPMCP) and HPMCT, we found that the fibers electrospun from HPMCP were thicker than that from HPMCT, which is attributed to the fact that the solution’s conductivity of HPMCT (containing two free carboxyl groups) is higher than that of HPMCP (containing only one free carboxyl group).

Transcription factor Oct4 plays critical roles in maintaining pluripotency and controlling lineage commitment of embryonic stem cells (ESCs). Our previous study indicates that Wwp2, a mouse HECT-type E3 ubiquitin ligase, ubiquitinates Oct4 and promotes its degradation in a heterologous system. However, roles of Wwp2 in regulating endogenous Oct4 protein levels as well as molecular characteristics of the function of Wwp2 have not been determined. Here, we report that Wwp2 plays an important role in Oct4 ubiquitination and degradation during differentiation of embryonal carcinoma cells (ECCs), although it does not appear to affect Oct4 protein levels in the undifferentiated ECCs and ESCs. Importantly, inhibition of Wwp2 expression by specific RNA interference elevates the Oct4 protein level, leading to attenuation in retinoid acid-induced activation of differentiation-related marker genes. Mechanistically, Wwp2 catalyzes Oct4 poly-ubiquitination via the lysine 63 linkage in a dosage-dependent manner. Interestingly, Wwp2 also regulates its own ligase activity in a similar manner. Moreover, auto-ubiquitination of Wwp2 occurs through an intra-molecular mechanism. Taken together, these results demonstrate a crucial role of Wwp2 in controlling endogenous Oct4 protein levels during differentiation processes of ECCs and suggest an interesting dosage-dependent mechanism for regulating the catalytic activity of the E3 ubiquitin ligase, Wwp2.

To assess the impact of surgical approaches and clinico-pathological parameters on the prognosis of localized renal cell carcinoma (RCC) after laparoscopic radical nephrectomy (LRN) or open radical nephrectomy (ORN). Between 2002 and 2008, 336 patients with localized RCC were treated at our two institutions. Of these, 261 were classified as clinical stage pT1 and 75 as pT2, the mean age was 52.3 years. One hundred forty-two patients underwent LRN, and 194 underwent ORN. The medical records of all patients were retrospectively reviewed. The mean follow-up was 44 months (12–84 months). The 3-, 5-, and 7-year cancer-specific survival (CSS) rates of LRN group (96.3, 94.6, and 92.5%, respectively) were equivalent to ORN (97.4, 94.2, and 91.4%, respectively). The mean CSS rates were not significantly different between LRN and ORN groups for either pT1 (82.3 vs. 81.6 months, P = 0.713) or pT2 (69.0 vs. 72.1 months, P = 0.729). Univariate analysis demonstrated significant impact of tumor stage (pT1 vs. pT2, P = 0.002) and tumor grade (G1/2 vs. G3/4, P = 0.045) on CSS. Surgical approach (laparoscopic or open) was not a statistically significant factor on CSS. Multivariate analysis identified that tumor stage was an independent prognostic factor for CSS of localized RCC (P = 0.007). Based on the long-term follow-up, our evaluation suggests that LRN is oncologically equivalent to ORN for patients with pT1 or pT2 tumors. Among the clinical variables, tumor stage appears to be an independent prognostic factor of CSS of localized RCC patients.

Rigid polyurethane foams were fabricated with five kinds of liquefied sugarcane bagasse polyols (LBP). The foams derived from sugarcane bagasse were investigated by thermogravimetric analysis (TGA), and the thermal degradation data were analyzed using the Coast-Redfern method and Ozawa method to obtain the reaction order and activation energy. The results indicate that the sugarcane bagasse-foams exhibit an excellent heat-resistant property, whereas their pyrolysis procedures are quite complicated. The reaction as first order only takes place from 250 to 400 °C, and the pyrolysis activation energies vary from 20 to 140 kJ/mol during the whole pyrolysis process.

A composite electrode of Pt nanoparticles coupled with tourmaline is prepared on glassy carbon (GC) disk electrode via electrodeposition. The nanocomposite of Pt/tourmaline is characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray powder diffraction, and transmission electron microscopy examinations linked with energy dispersive X-ray analysis. The electrocatalytic performance of the composite electrode (Pt/tourmaline/GC) is investigated in electrocatalysis oxidation of methanol at room temperature by cyclic voltammetry and chronoamperometry. It is indicated that Pt nanoparticles with size of ∼5 nm are uniformly assembled along the tourmaline particles and Pt exists in metallic and oxidated states confirmed by XPS. The results of electro-oxidation of methanol show that Pt/tourmaline catalyst is catalytically more active and stable than platinum-modified GC electrode, and the onset potential of Pt/tourmaline shifts 0.15 V to the negative side, and also the current density is significantly enhanced.

Smart polymer nanocontainers were formed by self-assembly of polyelectrolytes, which consist of chitosan and poly (N-isopropylacrylamide-co-acrylic acid). This is a novel easy method to synthesize smart nanocontainers. It was found that diameter and stability of the nanocontainers were changed by a variety of the environmental conditions.

The thermally-induced phase transformation behaviors of carboxylated poly(phenylene oxide)(CPPO)/polystyrene(PS), and PPO/PS blends were studied by using a difference-spectrum method of Fourier Transform Infrared Spectrometry (FTIR). The difference intensities(μ) and vibration frequency shifts(Δν) of the characteristic infrared absorption bands in both CPPO/PS and PPO/PS increased with raising temperature. A linear temperature dependence in the band frequency vs. temperature plots was observed for PPO/PS system, while three slopes corresponding to the three temperature ranges: below 190°C, 190°–215°C, and above 220°C, appeared in frequency-temperature curves for the CPPO/PS blend. These temperature ranges are consistent with the UCST area, the miscible area and the LCST area obtained by our previous works. The mechanism of phase transformation of CPPO/PS was discussed.