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Despite the great appeal of two-dimensional semiconductors for electronics and optoelectronics, to achieve the required charge carrier concentrations by means of chemical doping remains a challenge due to large defect ionization energies (IEs). Here, by decomposing the defect IEs into three parts based on ionization process, we propose a conceptual picture that the large defect IEs are caused by two effects of reduced dimensionality. While the quantum confinement effect makes the neutral single-electron point defect levels deep, the reduced screening effect leads to high energy cost for the electronic relaxation. The first-principles calculations for black phosphorus and MoS2 do demonstrate the general trend. Using BP monolayer either embedded into dielectric continuum or encapsulated between two hBN layers, we demonstrate the feasibility of increasing the screening to reduce the defect IEs. Our analysis is expected to help achieve effective carrier doping and open ways toward more extensive applications of 2D semiconductors.

To investigate the relation of blood arsenic concentration (BAC) with clinical effect and safety of arsenic-containing Qinghuang Powder (青黄散, QHP) in patients with myelodysplastic syndrome (MDS). Totally 163 patients with MDS were orally treated with QHP for 2 courses of treatment, 3 months as 1 course. The BACs of patients were detected by atomic fluorescence spectrophotometry at 1, 3, and 6 months during the treatment, and the effective rate, hematological improvement and safety in patients after treatment with QHP were analyzed. After 2 courses of treatment, the total effective rate was 89.6% (146/163), with 31.3% (51/163) of hematological improvement and 58.3% (95/163) of stable disease. The hemoglobin increased from 73.48 ± 19.30 g/L to 80.39 ± 26.56 g/L (P 0.05). Among 46 patients previously depended on blood transfusion, 28.3% (13/46) completely got rid of blood transfusion and 21.7% (10/46) reduced the volume of blood transfusion by more than 50% after treatment. The BACs were significantly increased in patients treated for 1 month with 32.17 ± 18.04 μ g/L (P 0.05). The adverse reactions of digestive tract during the treatment were mild abdominal pain and diarrhea in 14 cases (8.6%), and no patients discontinued the treatment. The BACs of patients with gastrointestinal adverse reactions were significantly lower than those without gastrointestinal adverse reactions (22.39 ± 10.38 vs. 37.89 ± 11.84, μ g/L, P

The efficiencies of ${\mathrm{Cu}}_{2}\mathrm{ZnSn}{\mathrm{Se}}_{4}$ (CZTSe) solar cells with a narrower band gap at 1.0 eV are currently higher than those of ${\mathrm{Cu}}_{2}\mathrm{ZnSn}{\mathrm{S}}_{4}$ (CZTS), with the optimal band gap according to the Shockley-Queisser model. To understand this abnormal observation, we studied the nonradiative recombination rates induced by the deep levels of the dominant defects in CZTSe, i.e., the ${\mathrm{Sn}}_{\mathrm{Zn}}(2+/+)$, ${\mathrm{Sn}}_{\mathrm{Zn}}(+/0)$, and $[{\mathrm{Cu}}_{\mathrm{Zn}}\text{\ensuremath{-}}{\mathrm{Sn}}_{\mathrm{Zn}}](+/0)$ levels. We found that the effective recombination centers in CZTS, namely, ${{\mathrm{Sn}}_{\mathrm{Zn}}}^{2+}$ and ${[{\mathrm{Cu}}_{\mathrm{Zn}}\text{\ensuremath{-}}{\mathrm{Sn}}_{\mathrm{Zn}}]}^{+}$, have much smaller carrier capture rates in CZTSe, and are less detrimental to the minority carrier lifetime and energy conversion efficiency. The smaller carrier capture rates for CZTSe can be attributed to the higher electronic transition energies, lower phonon frequencies, and weaker electron-phonon coupling effects in CZTSe compared to those in CZTS, because the large Se cations give rise to larger lattice constants and a softer lattice in CZTSe.

The damping capacity ( Q −1 ) of cast Mg-xY (x = 1, 3, 7 wt%) binary alloys were studied in aspects of yttrium (Y) content, heat treatment and pre-deformation. The relationship between amplitude and Q −1 fitted well with the G-L dislocation damping model for all the studied alloys. With Y content increasing from 1% to 7%, the Q −1 significantly decreased from 0.15 to 0.002 in the strain range of 10 −6 ∼10 −3 , while the yield strength increased from 20 ± 2 MPa to 92 ± 4 MPa. The solid solution heat treatment (T4, 793 K × 6 h) markedly improved the Q −1 , because the movement of dislocations was impeded by more Y solute atoms as weak pinning points. The 25% pre-deformation reduced the Q −1 value of T4 treated Mg-1Y alloys by half, which may result from the increased dislocation density due to work hardening and the decreased stacking fault energy by the Y addition. Moreover, both the pre-deformation and increasing Y content extended the critical strain amplitude e c . The Mg-Y alloys exhibited promising potential for developing high-performance damping alloys based on comparing with several Mg-based damping alloys in terms of both damping capacity and strength.

The graphite-filled polyurethane/poly(methyl methacrylate-butyl methacrylate) (PU/P(MMA-BMA)) semi-interpenetrating polymer networks (IPNs) were synthesized by sequential method. The influences of graphite particle content and size on the 60/40 PU/P(MMA-BMA) IPNs were studied. The damping properties of IPN composites were evaluated by dynamic mechanical thermal analysis (DMA) and cantilever beam resonance methods. The mechanical performances were investigated using tensile and hardness devices. DMA results revealed that the incorporation of graphite particles improved damping properties of IPNs significantly. The 5% graphite-filled IPN composite exhibited the widest temperature range and the highest loss factor (tan δ) when the test frequency was 1 Hz. As to the damping properties covering a wide frequency range from 1 to 3,000 Hz, the addition of graphite particles broadened the damping frequency range (Δf, where tan δ is above 0.3) and increased the tan δ value of IPNs. Among them, the composite with 7.5% graphite showed the best damping capacity. And the hardness and the tensile strength of IPN composites were also improved significantly. POLYM. COMPOS., 2013 © 2013 Society of Plastics Engineers

Polyurethane/poly (methylacrylate-butylmethacrylate-2-Hydroxyethylmethacrylate) Interpenetrating polymernetworks (IPNs) were prepared by sequential polymerization. Their glass transition performance was measured by using differential scanning calorimetry (DSC). DSC results revealed there are three glass transition temperatures (Tg) for both IPNs samples. Their damping properties were evaluated according to ASTM E756-05. Their loss factor (tan δ>0.3) from 10-1300Hz displays a wide temperature range of 94°C.

To investigate the effects of Propyl Gallate (PrG) on cellular adhesion between human To investigate the effects of Propyl Gallate (PrG) on cellular adhesion between human umbilical vein endothelial cells (HUVEC) and polymorphonuclear leukocytes (PMN) as well as the expression umbilical vein endothelial cells (HUVEC) and polymorphonuclear leukocytes (PMN) as well as the expression of intercellular adhesion molecule-1 (ICAM-1, CD54) and E-selectin (CD62E) on the VEC surface. of intercellular adhesion molecule-1 (ICAM-1, CD54) and E-selectin (CD62E) on the VEC surface.A human VEC inflammation model was induced by tumor necrosis factor alpha (TNF-alpha). VECs were pre- A human VEC inflammation model was induced by tumor necrosis factor alpha (TNF-alpha). VECs were preincubated with varying concentrations of PrG (0.001-5 mmol/L) or 1 per thousand DMSO (v:v) or 10 mmol/L acetylsalicylic incubated with varying concentrations of PrG (0.001-5 mmol/L) or 1 per thousand DMSO (v:v) or 10 mmol/L acetylsalicylic acid (ASA) for 1 h, and then were stimulated with 10 ng/mL TNF-alpha for 6 h. Rose bengal vital staining method acid (ASA) for 1 h, and then were stimulated with 10 ng/mL TNF-alpha for 6 h. Rose bengal vital staining method was used to measure the adherence rate of PMN to VEC, while flow cytometry was used to determine the was used to measure the adherence rate of PMN to VEC, while flow cytometry was used to determine the expression of CD54 and CD62E on the VEC surface. expression of CD54 and CD62E on the VEC surface.After 6 h of incubation with TNF-alpha, the adherence After 6 h of incubation with TNF-alpha, the adherence of PMN to HUVECs as well as the percentage of fluorescence-positive cells and mean fluorescence intensity of PMN to HUVECs as well as the percentage of fluorescence-positive cells and mean fluorescence intensity (MFI) of surface CD54 and CD62E in HUVECs increased significantly ( (MFI) of surface CD54 and CD62E in HUVECs increased significantly (P0.01). Pre-treatment of HUVECs with0.01). Pre-treatment of HUVECs with PrG (0.1-5 mmol/L) significantly suppressed the adherence of PMN to VECs induced by TNF-alpha (PrG (0.1-5 mmol/L) significantly suppressed the adherence of PMN to VECs induced by TNF-alpha (P0.05). PrG0.05). PrG (1-5 mmol/L) inhibited the VEC surface expression of CD62E and CD54 in a dose-dependent way ( (1-5 mmol/L) inhibited the VEC surface expression of CD62E and CD54 in a dose-dependent way (P0.05). PrG0.05). PrG at lower concentrations (0.001-0.1 mmol/L) showed no effect on CD54 expression, while it showed a slightly at lower concentrations (0.001-0.1 mmol/L) showed no effect on CD54 expression, while it showed a slightly increasing trend in CD62E expression (increasing trend in CD62E expression (P0.05). ASA at 10 mmol/L had no obvious effect on the positive rate of0.05). ASA at 10 mmol/L had no obvious effect on the positive rate of CD62E and CD54. CD62E and CD54.High concentrations of PrG (0.1-5 mmol/L) exert its inhibitory effect on cellular High concentrations of PrG (0.1-5 mmol/L) exert its inhibitory effect on cellular adherence of PMN to HUVECs, and its mechanism may be related to inhibiting surface expression of CD54 and adherence of PMN to HUVECs, and its mechanism may be related to inhibiting surface expression of CD54 and CD62E in HUVECs. Its action concentration was lower than that of ASA. CD62E in HUVECs. Its action concentration was lower than that of ASA.

The calcineurin pathway has been reported to be essential for the development of azole resistance in Candida albicans. The depletion or ectopic over-expression of RTA2 increased or decreased susceptibility of C. albicans to azoles, respectively. CaCl(2)- induced activation of the calcineurin pathway in wildtype C. albicans promoted resistance to azoles, while the Ca(2+) chelator (EGTA), calcineurin inhibitors (FK506 and cyclosporin A) and the deletion of RTA2 blocked the resistance-promoting effects of CaCl(2). Furthermore, we found that RTA2 was up-regulated in a calcineurin-dependent manner. The depletion of RTA2 also made the cell membrane of C. albicans liable to be destroyed by azoles and RTA2 over-expression attenuated the destroying effects. Finally, the disruption of RTA2 caused an increased accumulation of dihydrosphingosine (DHS), one of the two sphingolipid long-chain bases, by decreasing release of DHS. In conclusion, our findings suggest that RTA2 is involved in calcineurin-mediated azole resistance and sphingoid long-chain base release in C. albicans.

Objective This study was designed to investigate the effect of Panax notoginseng saponin (PNS) on platelet adhesion to injured endothelial cells (ECs) and platelet activation induced by injured ECs, and to explore its underlying mechanisms. Methods Human umbilical vein endothelial cells (HUVECs) pretreated with aspirin (ASA,15 μg/mL) or PNS (160 μg/mL), or neither, were exposed to oxidized low-density lipoprotein (ox-LDL,80 mg/L) for 16 h. Platelets were then added and co-cultured with HUVECs for 5 min. Platelet adhesion to ECs, platelet CD62p expression, and HUVEC apoptosis were assessed by fluorescence activated cell sorting (FACS)·Supernatant concentration of 6-keto-PGF1α and thromboxane 2 (TXB 2 ) were measured by radioimmunoassay. Cyclooxygenase-1 (COX-1) and COX-2 protein expression were measured by western blotting. Results The inhibitory effect of PNS on platelet activation was similar to ASA, but the inhibitory effect of PNS on platelet adhesion to ECs was superior to ASA. PNS modulated COX-2 expression, and increased 6-keto-PGF1α concentration in HUVECs, while down-regulated COX-1 expression and decreased supernatant TXB 2 concentration in platelets. Co-culturing of injured HUVECs with platelets increased HUVEC apoptosis induced by ox-LDL compared with HUVECs cultured without platelets; ASA increased HUVEC apoptosis induced by ox-LDL when cultured without platelets, while decreased the apoptosis when co-cultured with platelets. Conclusions EC protection by ASA is closely associated with its inhibitory effect on platelet activation. PNS is superior to ASA in protecting ECs and in inhibiting platelet adhesion to injured ECs, and the regulation of COX pathway in both ECs and platelets might be the underlying mechanisms of PNS.

CaIPF7817, a functionally unknown gene in Candida albicans, was suggested to be involved in the redox system previously, but its exact role is unknown. In this study, ipf7817 null mutant was generated with the URA-blaster method. After the deletion of CaIPF7817, intracellular levels of reactive oxygen species were significantly increased; mitochondrial membrane potential, a direct indicator of mitochondrial function, was elevated; some important redox-related genes, including GLR1, SOD2, and TRR1, were up-regulated; and the GSH/GSSG ratio was raised. These changes indicated that CaIPF7817 played important roles in the regulation of redox homeostasis in C. albicans.

Ethnopharmacological relevance Panax quinquefolium saponin (PQS) is the active component extracted from traditional Chinese medicine Panax quinquefolius L. and has been widely used as a supplement to dual antiplatelet drugs (DA) for treatment of coronary artery disease (CAD) for two decades; however, the efficacy of PQS combined with DA against platelet adhesion to endothelial cells (ECs), an essential step in thrombosis, remains unclear. Aim of the study To compare PQS combined with DA and DA alone in inhibiting platelet adhesion to injured human umbilical vein endothelial cells (HUVECs) and to explore the possible mechanisms focusing on PI3K/AKT, COX-2/6-keto-PGF 1α , and COX-1/TXB 2 pathways. Methods HUVECs injured by oxidized low-density lipoprotein (ox-LDL) were randomly allocated into control, model, DA, PQS+DA (P+DA), LY294002 (a PI3K inhibitor)+DA (L+DA), and LY294002+PQS+DA (LP+DA) groups. HUVEC apoptosis, platelet adhesion to injured HUVECs, and platelet CD62p expression were assayed by fluorescence activated cell sorting (FACS). The concentrations of 6-keto-PGF 1α and TXB 2 in the supernatant were measured by radioimmunoassay. Protein expression of phosphorylated-PI3K, PI3K, phosphorylated-AKT, AKT, COX-1, and COX-2 in both platelets and HUVECs was evaluated by western blot. Results Compared to DA alone, PQS combined with DA reduced platelet adhesion to HUVECs and HUVEC apoptosis more potently, increased the concentration of supernatant 6-keto-PGF 1α and up-regulated phospho-AKT protein in HUVECs. LY294002 mitigated the effects of PQS on HUVEC apoptosis and platelet adhesion. Conclusions These findings show that PQS as a powerful supplement to DA, attenuated HUVEC apoptosis and improved the DA-mediated reduction of platelet adhesion to injured HUVECs and the underlying mechanisms may be associated with PI3K/AKT and COX pathways in HUVECs and platelets. PQS might provide a new complementary approach to improve the prognosis of thrombotic diseases in future.

To explore the significance of platelet activation (PA) in patients with unstable angina pectoris (UA) and the effect of Xuefu Zhuyu pill (XZP, a Chinese composite recipe) on it, by way of determining platelet membrane glycoprotein CD62P, CD41/CD45 expressions in whole blood of healthy persons and UA patients. XZP was given orally to 45 UA patients for 2 weeks. Their expressions of CD62P and CD41/CD45 in peripheral blood were determined before and after treatment by whole blood flow cytometry with special marked antibody, and compared with those in 10 healthy persons of the same age as a normal control group. Amount of expressions of CD62P and CD41/CD45 (FC%) in UA patients before treatment were 24. 22±7. 92 and 25. 89±8.10 respectively, all higher than those in the control group (P 0.05) . Platelet adhesion rate reduced significantly (P

Trehalose, a nonreducing disaccharide which accumulates dramatically during stationary phase or under oxidative stress, is well known as a stress protectant in several organisms. Here we investigated the putative correlation of trehalose with Cap1p, which is a basic region-leucine zipper (bZip) transcription factor participating in oxidative stress tolerance in Candida albicans. HPLC-MS analysis showed that trehalose did not accumulate in the cap1/cap1 mutant during stationary phase. When the mutant was exposed to high concentration of H2O2, trehalose accumulation was still not induced. Under both of the conditions above, the cap1/cap1 mutant showed high sensitivity to H2O2, and the cell viability was rather low. Furthermore, when exogenous trehalose was added to the culture of the cap1/cap1 mutant, the tolerance of this strain to oxidative stress was increased. Real time reverse transcription polymerase chain reaction (RT-PCR) analysis revealed that the transcript levels of TPS2 and TPS3 were increased in the wild type strain compared to that in cap1/cap1 mutant when exposed to H2O2. These results indicated that trehalose accumulation is important to the oxidative stress tolerance mediated by Cap1p in C. albicans.

Candidiasis can be associated with the formation of biofilms on bioprosthetic surfaces. The intrinsic resistance of Candida albicans biofilms to the most commonly used antifungal agents has been demonstrated. Here we examined the effect of baicalein (BE) on C. albicans biofilm formation. Confocal laser scanning microscopy showed that C. albicans biofilm was inhibited and growth was predominantly composed of yeast cells and pseudohyphae. The effect of inhibition was dose-dependent. Over 70% inhibition of biofilms was observed at BE concentrations between 4 microg/mL and 32 microg/mL. Moreover, BE was active against different growth stages of biofilms, with 89% and 52% inhibition when BE was added at 0 h and 24 h of the incubation period, respectively. The water-hydrocarbon two-phase assay showed a decrease in cell surface hydrophobicity in the BE-treated groups compared with the control group. Consistent with this, real-time reverse transcriptase polymerase chain reaction (RT-PCR) results showed that BE-treated cells expressed lower levels of CSH1 mRNA than cells grown in the absence of BE. Our data provide useful information for the development of new strategies to reduce the incidence of device-associated infections.

To study the cytotoxicity induced by haematoporphyrin monomethyl ether (HMME)-mediated sonodynamic therapy (SDT) on C6 glioma cells.The potent photosensitizer HMME was used as the sensitizer. Rat C6 glioma cells were incubated with HMME (10 microg/mL) in the dark for 2 h and then subjected to ultrasound treatment at 1.0 MHz and 0.5 W/cm2 for 2 min. The growth inhibition rate at different time points after SDT was determined by MTT assay. The apoptotic rate and cell circle profiles were examined with flow cytometry. Fine structures were observed with transmission electron microscope (TEM). The sonodynamic effect on the glioma cells was also studied in the absence or presence of various reactive oxygen species (ROS) scavengers.The growth inhibition rate of C6 glioma cells after SDT significantly increased. SDT also increased the apoptosis and proliferation rate (APR). TEM examination showed the morphological features of apoptosis or necrosis. The addition of NaN(3) showed a strong protective effect again SDT.Our data indicated that SDT could kill C6 glioma cells in vitro and possibility through induction of apoptosis and necrosis. Singlet oxygen ((1)O2) may play an important role in SDT.

The damping behaviors of Fe-13Cr-2.5Mo alloy at ambient temperatures and the AC magnetic field are tested with the improved reversal torsion machine. The precipitations distributing in the annealed alloy are also observed with SEM. The results show that because the defections decrease during the annealing treatment, causing a higher damping capacity of this alloy. This damping drops linearly to 63% when the ambient temperature changes from 23 o C to 500 o C, resulting from the gradual decrease of ferromagnetism. On the other hand, the AC magnetic field causes the damping capacity to drop sharply, and finally it reaches a much lower level.