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The study objective was to observe the treatment effect of the farnesoid X receptor (FXR) agonist GW4064 in a rat model of hilar cholangiocarcinoma to explore a new therapeutic target for gene therapy for hilar cholangiocarcinoma. Eighty male Wistar rats were randomly divided into four groups (treatment group, model group, control group and sham operation group, 20 rats in each group). The four groups were fed a standard diet. The treatment group and the model group were injected with a suspension of cholangiocarcinoma QBC939 cells into the hilar bile duct with a microsyringe, the control group was injected with normal saline, and the sham operation group was not injected with anything. A modified tail suspension test (TST) was used to evaluate the vitality of the rats. At 4 weeks, one rat in the treatment group and model group was euthanized, and the changes in the hilar bile duct were recorded. The procedure was repeated at 6 weeks. After 6 weeks, hilar cholangiocarcinoma occurred in the treatment group and model group. Then, the treatment group was injected with GW4064 intraperitoneally at a dose of 50 mg/kg/day. One week after injection, the rats in the four groups were euthanized. Pathological examination confirmed that tumours had formed, and hilar bile duct tissues were taken from the four groups. FXR, Bsep, Ntcp and NF-κB expression in the hilar bile duct was detected by real-time polymerase chain reaction (RT–PCR) and immunohistochemistry. After three weeks, the rats in the treatment group and model group ate less, and their weight was significantly reduced. Six weeks later, hilar cholangiocarcinoma was detected in the treatment group and model group. After treatment with GW4064, the ratios of FXR/GAPDH mRNA, Bsep/GAPDH mRNA, Ntcp/GAPDH mRNA and NF-κBp65/GAPDH mRNA were significantly different among the four groups. Under a light microscope, FXR protein reacted with anti-FXR antibody, Bsep protein reacted with anti-Bsep antibody, Ntcp protein reacted with anti-Ntcp antibody and NF-κBp65 protein reacted with anti-NF-κBp65 antibody, and they showed granular expression. Every pathological section included 4,800 cells, and there were different numbers of positive cells in each group. FXR expression in the hilar cholangiocarcinoma of rats was significantly lower than that in normal hilar bile duct tissues. GW4064 increased the expression of FXR in tumour tissues. These findings suggest that FXR may be a new therapeutic target and that GW4064 may be helpful in the treatment of hilar cholangiocarcinoma. [ABSTRACT FROM AUTHOR]

Aiming at the high cost of quantum equipment and the difficulty of preparing discrete variable quantum states, a measurement-device-independent continuous variable semi-quantum key distribution (MDI-CV-SQKD) protocol is proposed. We, respectively, give the prepared-measure model and the entanglement-based (EB) model of the MDI-CV-SQKD protocol. Based on the EB model, we analyze the secret key rate and other performance of the protocol and perform numerical simulations. Then we analyze the amount of information transmitted by the channel under different attacks. As long as the channel parameters meet certain conditions, secure communication can be carried out. Through parameter adjustment, the solution can achieve the maximum secret key rate. The protocol has the advantages of easy preparation of continuous variables quantum states, low cost of semi-quantum user equipment, and high utilization of full quantum users. It also has characteristics such as the unconditional security of the full quantum protocol, the resistance to the detector side-channel attack of the measurement-device-independent protocol, and the extension of the transmission distance. Therefore, this protocol has important practical value. [ABSTRACT FROM AUTHOR]

Background: Establish patient-derived tumor xenograft (PDTX) from advanced GICs and assess the clinical value and applicability of PDTX for the treatment of advanced gastrointestinal cancers. Methods: Patients with advanced GICs were enrolled in a registered multi-center clinical study (ChiCTR-OOC-17012731). The performance of PDTX was evaluated by analyzing factors that affect the engraftment rate, comparing the histological consistency between primary tumors and tumorgrafts, examining the concordance between the drug effectiveness in PDTXs and clinical responses, and identifying genetic variants and other factors associated with prognosis. Results: Thirty-three patients were enrolled in the study with the engraftment rate of 75.8% (25/33). The success of engraftment was independent of age, cancer types, pathological stages of tumors, and particularly sampling methods. Tumorgrafts retained the same histopathological characteristics as primary tumors. Forty-nine regimens involving 28 drugs were tested in seventeen tumorgrafts. The median time for drug testing was 134.5 days. Follow-up information was obtained about 10 regimens from 9 patients. The concordance of drug effectiveness between PDTXs and clinical responses was 100%. The tumor mutation burden (TMB) was correlated with the effectiveness of single drug regimens, while the outgrowth time of tumorgrafts was associated with the effectiveness of combined regimens. Conclusion: The engraftment rate in advanced GICs was higher than that of other cancers and meets the acceptable standard for applying personalized therapeutic strategies. Tumorgrafts from PDTX kept attributes of the primary tumor. Predictions from PDTX modeling closely agreed with clinical drug responses. PDTX may already be clinically applicable for personalized medication in advanced GICs. [ABSTRACT FROM AUTHOR]

The original magnesium slag has poor desulfurization activity, so modification treatments are needed to improve its desulfurization activity. In this article, magnesium slag was modified by quenching hydration. The crystal structure and morphology characteristics were obtained by XRD and TEM. And to further understand the relationship between crystal structure and desulfurization performance, desulfurization experiments were carried out by TGA. A theoretical basis for future development of desulfurization methods was provided, which could not only alleviate the disposal problem but also help control SO2 pollution. The results showed that the naturally cooled magnesium slag was mainly composed of γ-C2S and β-C2S. The irregular coordination of Ca2+ in β-C2S was the main reason that the hydration activity of β-C2S was higher than that of γ-C2S. With the increase of quenching temperature, the β-C2S content increased continuously, promoting the formation of C–S–H with developed pore structure. With the increasing hydration temperature, the hydration reaction of β-C2S could be promoted, and more amorphous C–S–H could be generated. The hydration product C–S–H enhanced the physical adsorption capacity, and the increase of crystal structure defects enhanced the chemical adsorption capacity. At 950 °C quenching temperature and 90 °C hydration temperature, the desulfurization activity was the highest. [ABSTRACT FROM AUTHOR]

Phenolic compounds in apples 17 cultivars (Malus domestica Borkh.) and 3 wild forms (Malus sp.) were analyzed to study the impact of genetic background, growth site, and fruit bagging. The impact of altitude was studied in nine cultivars by analyzing fruits collected from orchards at three altitudes. Procyanidin B2 (71–628 μg/g fresh weight), (−)-epicatechin (35–357 μg/g), and chlorogenic acid (28–563 μg/g) were always the three most abundant phenolic compounds in the apple samples studied, except for the cultivar 'Qinguan', which had a very low content of (−)-epicatechin (13 μg/g) and procyanidin B2 (8 μg/g). The wild apples of M. prunifolia (Willd.) Borkh were 5-times richer in epicatechin (278 μg/g) and procyanidin B2 (628 μg/g) than the commercial cultivars of M. domestica Borkh (86 and 54, respectively). Among the commercial cultivars, 'Qinguan' had the highest level of chlorogenic acid but the lowest content of flavan-3-ols, whereas 'Liuyuehong' was characterized by the highest content of quercetin glycosides. Procyanidin B2, and (−)-epicatechin correlated negatively, while other phenolics positively, with altitude. The response of phenolic compounds to altitude variation depended on latitude variation and genetic backgrounds. Bagging treatment reduced the contents of most phenolic compounds, with the impact of cultivars and length of re-exposure before harvest. This is also the first report on phenolic compounds in several important new cultivars, adding new knowledge on the compositional characteristics of global apple resources. [ABSTRACT FROM AUTHOR]

Molecular hydrogen (H2) is a physiologically inert gas. However, during the last 10 years, increasing evidence has revealed its biological functions under pathological conditions. More specifically, H2 has protective effects against a variety of diseases, particularly nervous system disorders, which include ischemia/reperfusion injury, traumatic injury, subarachnoid hemorrhage, neuropathic pain, neurodegenerative diseases, cognitive dysfunction induced by surgery and anesthesia, anxiety, and depression. In addition, H2 plays protective roles mainly through anti-oxidation, anti-inflammation, anti-apoptosis, the regulation of autophagy, and preservation of mitochondrial function and the blood-brain barrier. Further, H2 is easy to use and has neuroprotective effects with no major side-effects, indicating that H2 administration is a potential therapeutic strategy in clinical settings. Here we summarize the H2 donors and their pharmacokinetics. Meanwhile, we review the effectiveness and safety of H2 in the treatment of various nervous system diseases based on preclinical and clinical studies, leading to the conclusion that H2 can be a simple and effective clinical therapy for CNS diseases such as ischemia-reperfusion brain injury, Parkinson's disease, and diseases characterized by cognitive dysfunction. The potential mechanisms involved in the neuroprotective effect of H2 are also analyzed. [ABSTRACT FROM AUTHOR]

Introduction: This systematic review aims to verify the efficacy of acarbose monotherapy in treating obese or overweight patients without diabetes.Methods: In the study, we conducted a systematic search of the Pub-Med, EMBASE, Cochrane and Science Citation Index Expanded databases in search of clinical trials on acarbose treatment, overweight and obesity. The crucial inclusion criteria were as follows: (1) patients were diagnosed as overweight or obese (BMI ≥ 25 kg/m2); (2) randomized controlled trials (RCTs); (3) patients had undergone acarbose monotherapy or placebo control; (4) acarbose treatment had been carried out for at least 3 months. Exclusion criteria were as follows: (1) patients diagnosed with diabetes mellitus (DM); (2) patients had received a weight loss medication or surgery in the past 3 months; (3) papers not published in English; (4) repeated research results of the same experiment or repeated published documents.Results: A total of 7 studies involving 132 in the acarbose group and 137 in placebo group, 269 subjects in total, were included in this meta-analysis. From the selected seven papers, we extracted the following clinical parameters: systolic blood pressure (SBP), diastolic blood pressure (DBP), body weight (BW), body mass index (BMI), triglyceride (TG), total cholesterol (TC), low density lipoprotein (LDL), high density cholesterol (HDL) and fasting plasma glucose (FPG). An important finding of our research is that TG was the only significantly reduced parameter in the acarbose group. Weight mean difference (WMD) was - 0.21 (95% CI - 0.33, - 0.09) mmol/l between acarbose (P = 0.0006) and placebo patients. Reduction of BMI was also greater for acarbose than placebo subjects, although the discrepancy was not statistically significant (P = 0.56). Moreover, no hypoglycemia occurred in either the acarbose group or placebo group. A few subjects experienced gastrointestinal reactions, but these were mild and improved over time. Acarbose has no obvious influence on other metabolic indexes.Conclusion: Acarbose monotherapy is beneficial in reducing TG levels in obese or overweight patients and will not result in hypoglycemia during medication. The side effects of acarbose are mild. [ABSTRACT FROM AUTHOR]

Increased blood pressure variability (BPV) has been proved to be associated with cardiovascular morbidity and mortality. It is of great significance to elucidate the mechanism of BPV increase. The cation channel transient receptor potential canonical 6 (TRPC6) is involved in a series of cardiovascular disease. Our experiment aimed to explore the role of TRPC6 in the development of BPV increase. Sino-aortic denervation (SAD) operation was applied to establish the model of BPV increase in rats. The BPV was presented as the standard deviation to the mean of systolic or diastolic blood pressure every 1 h during 12 h of the light period. SAD was performed in male Sprague Dawley (SD) rats at the age of 10 weeks. At 8 weeks after SAD operation, the hemodynamic parameters were determined non-invasively via a Rodent Blood Pressure Analysis System. The TRPC6 expressions in myocardial and thoracic aortic tissue was determined utilizing Western Blot, immunofluorescence and quantitative RT-PCR. The expression of TRPC3 was detected as well. To investigate whether TRPC6 was a causative factor of BPV increase in SAD rats, TRPC6 activator and inhibitor with three progressively increasing doses were intraperitoneally injected to the SAD rats. We found that SAD rats presented significant augmentation of systolic and diastolic BPV with no change of BP level and heart rate. The mRNA and protein expression levels of TRPC6 in myocardial and thoracic aortic tissue in SAD rats were substantially increased, but there was no obvious change in TRPC3 expression. The systolic and diastolic BPV increase were dose-dependently exacerbated after TRPC6 activation with GSK1702934A but were dose-dependently attenuated after TRPC6 inhibition with SAR7334. In Conclusion, the TRPC6 (but not TRPC3) expressions in myocardial and thoracic aortic tissue were substantially increased in SAD rats, and TRPC6 probably played an important role in the development of BPV elevation. [ABSTRACT FROM AUTHOR]

Background: The role of laparoscopic liver resection (LLR) for lesions located in posterosuperior (PS) segments remains a matter of development to be further assessed. This systematic review aims to compare the short-term and oncological outcomes between laparoscopic and open liver resection (OLR) in PS lesions.Methods: EMBASE, MEDLINE and Cochrane Library were searched from date of inception to June 2019. This meta-analysis was performed using the STATA 12.0 statistical software. Standardized mean differences (SMDs), odds ratios (ORs) and hazard ratios (HRs) were calculated for continuous variables, dichotomous variables and long-term variables, respectively, with 95% confidence intervals (CIs).Results: A total of 788 patients from eight studies were identified for the final analysis, with 371 patients in the LLR group and 417 in the OLR group. Although the operation time (SMD 0.22; 95% CI 0.08-0.36; P = 0.003) was longer whereas overall complication rate (OR 0.50; 95% CI 0.36-0.70; P < 0.001) and postoperative hospital stay (SMD - 0.45; 95% CI - 0.59 to - 0.30; P = 0.003) were lower in the LLR group than in the OLR group, no significant differences in blood loss (SMD - 0.14; 95% CI - 0.28 to 0.00; P = 0.054), transfusion rate (OR 0.92; 95% CI 0.56-1.54; P = 0.764), major complication rate (OR 0.63; 95% CI 0.38-1.05; P = 0.079), R0 resection rate (OR 1.04; 95% CI 0.55-1.96; P = 0.902), and disease-free survival (DFS) for hepatocellular carcinoma (HCC) (HR 1.43; 95% CI 0.95-2.17), DFS for colorectal liver metastases (HR 1.05; 95% CI 0.61-1.81), overall survival for HCC (HR 1.00; 95% CI 0.43-2.30) were noted between the groups.Conclusion: LLR is technically feasible and safe without compromising long-term oncological outcomes for selected patients with lesions in the PS segments of the liver. [ABSTRACT FROM AUTHOR]

Phenethyl-bridged DOPO derivative (DiDOPO) was combined with graphene nanosheets (GNSs) in epoxy resin (EP) to improve its flame retardancy. The results indicated that the introduction of only 1.5 wt% DiDOPO/1.5 wt% GNS in EP increased the limited oxygen index (LOI) from 21.8% to 32.2%, hence meeting UL 94 V-0 rating. The thermogravimetric analyses revealed that char yield rose in presence of GNSs to form thermally stable carbonaceous char. The decomposition and pyrolysis products in gas phase were characterized by thermogravimetry-Fourier transform infrared spectroscopy (TG-FTIR), and the release of large amounts of phosphorus was detected in the gas phase. The evaluation of flame-retardant effect by cone calorimetry demonstrated that GNSs improved the protective-barrier effect of fire residue of EP/DiDOPO/GNS. The latter was further confirmed by digital photography and scanning electron microscopy (SEM). Also, Raman spectroscopy showed that GNSs enhanced graphitization degree of the resin during combustion. Overall, the combination of DiDOPO with GNSs provides an effective way for developing high-performance resins with improved flame retardancy. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the efficacy of metformin versus a placebo in the treatment of patients with simple obesity without obesity related diseases.Methods: A search was done on Pub-Med, EMBASE, Cochrane, and Science Citation Index Expanded databases. The main inclusion criteria included the following:(1) randomized controlled trials. (2) patients diagnosed as being overweight or obese. (3) patients were randomly assigned to receive metformin or control. Exclusion criteria included the following: patients diagnosed with an obesity related disease, such as diabetes mellitus (DM) or polycystic ovary syndrome (PCOS).Results: Compared with the placebo, weighted mean difference (WMD) was 2.33 (95% CI 0.31, 4.35) kg higher with metformin (p = 0.02). Compared with the placebo, WMD was 0.57 (95% CI 0.35, 0.79) kg/m² higher with metformin(p < 0.00001). There was no significant difference in the reduction of waist circumference between the metformin group and the control group (p = 0.05). The fasting blood glucose levels were significantly lower in the metformin group than in the control group (p < 0.00001). However, no hypoglycemia was noted in the metformin group or the control group.Conclusion: Metformin is effective in reducing body weight of simple obesity patients, and metformin does not induce hypoglycemia as a side effect. [ABSTRACT FROM AUTHOR]

Previous studies showed that, in chronic lymphocytic leukemia (CLL) patients with isolated 13q deletion (13q-), those carrying higher percentage of leukemic cells with 13q- had more aggressive diseases. However, the prognostic value of the percentage of leukemic cells with 13q- in Chinese CLL patients with isolated 13q- remained to be determined. Using interphase fluorescence in situ hybridization (FISH), we identified 82 patients (25.4%) with isolated 13q deletion from a cohort of 323 untreated CLL patients. Among patients with isolated 13q deletion, cases of 13q- cells ≥ 80% (13q-H) had significantly shorter time to first treatment (TTT) than those of < 80% 13q- cells (13q-L) (median 11 vs. 92 months, p = 0.0016). A higher lymphocyte count (p = 0.0650) was associated with 13q-H, while other clinical, immunophenotypic, or molecular features did not differ between patients with 13q-H and 13q-L. Although 13q-H only showed marginal significance in multivariate analysis of TTT (hazards ratio 2.007; 95% confidence interval 0.975-4.129; p = 0.059), it helped refine the risk stratification based on Binet stage or immunoglobulin heavy chain variable gene (IGHV) status. In cases in Binet A or B stage, patients with 13q-H had a significantly shorter TTT (median TTT 18 months vs. undefined, p = 0.0101). And in IGHV mutated patients, 13q-H was also associated with reduced TTT (median TTT 13q-H. 18 months vs. 13q-L undefined, p = 0.0163). In conclusion, the prognosis of CLL patients with isolated 13q deletion was heterogeneous with 13q-H identifying patients with worse outcome. [ABSTRACT FROM AUTHOR]

Abstract: Trimetazidine (TMZ) has been demonstrated to have protective effects against myocardial ischemia/reperfusion (MI/R) injury. In the present study, we investigated the effects and the underlying mechanisms of TMZ on autophagy during MI/R in vivo and in vitro. In the in vivo study, an animal model of MI/R was induced by coronary occlusion. TMZ (20 mg/kg/day) protected the rat hearts from MI/R-induced heart failure by increasing ejection fraction and fractional shortening and decreasing end-systolic volume, end-diastolic volume, left ventricular (LV) internal diameter at systole, and LV internal diameter at diastole; it alleviated myocardial injury and oxidative stress by decreasing LDH, creatine kinase MB isoenzyme, ROS, and MDA levels and increasing SOD and glutathione peroxidase levels in plasma. TMZ also reduced myocardial infarct size and apoptosis. Moreover, TMZ markedly inhibited MI/R-induced autophagy by decreasing the protein and messenger RNA levels of LC3-II, Beclin1, ATG5, and ATG7 and the number of autophagosomes and by involving the AKT/mTOR pathway. Further, in the in vitro experiments, H9c2 cells were incubated with TMZ (40 μM) to explore the direct effects of TMZ following exposure to hypoxia and reoxygenation (H/R). TMZ increased cell viability and the concentration of intracellular SOD and inhibited H/R-induced cell apoptosis and ROS production. Moreover, TMZ decreased the number of autophagosomes and autophagy-related protein expression; it also upregulated p-AKT and p-mTOR expression. In addition, TMZ augmented Bcl-2 protein expression and diminished Bax protein expression, the Bax/Bcl-2 rate, and cleaved caspase-3 level. However, these effects on H9c2 cells were notably abolished by the PI3K inhibitor LY294002. In conclusion, our results showed that TMZ inhibited I/R-induced excessive autophagy and apoptosis, which was, at least partly, mediated by activating the AKT/mTOR pathway.Key messages: TMZ improved cardiac function, alleviated myocardial injury and oxidative stress, and reduced the myocardial infarct area and apoptosis.TMZ inhibited MI/R-induced myocardial autophagy, H/R-induced H9c2 cell apoptosis, and autophagy flux.The effect of TMZ on autophagy was repressed by LY294002.TMZ protected against MI/R injury by inhibiting excessive autophagy via activating the AKT/mTOR pathway. [ABSTRACT FROM AUTHOR]

α-asarone (ASR) is a major bioactive compound isolated from the rhizome of Acorus tatarinowii Schott and it has extensive biological effects. Clinically, anxiety disorder is a common comorbidity of chronic pain. However, limited information is available regarding the effects of ASR on chronic pain-related anxiety. This study aims to evaluate the anxiolytic effects of ASR in chronic pain mice. Chronic inflammatory pain was induced by hind-paw injection of complete Freund's adjuvant (CFA). Behavioral tests, western-blot analysis and whole-cell patch recordings were performed to evaluate the subsequent events. We found that ASR induced anxiolytic activities in CFA-injected mice but did not affect the nociceptive threshold. ASR administration reversed the up-regulation of GluR1-containing α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, NR2A-containing N-methyl-D-aspartate (NMDA) receptors and down-regulation of γ-aminobutyric acid A (GABA) receptors in the basolateral amygdala (BLA) of CFA-injected mice. Electrophysiological data revealed that ASR treatment restored the balance between excitatory and inhibitory neurotransmissions, which was disturbed in the BLA of CFA-injected mice. Moreover, ASR prevented the hyper-excitability of pyramidal neurons in the BLA of chronic pain mice. Our results suggested that the anxiolytic effects of ASR were partially due to maintaining the balance between excitatory/inhibitory transmissions and attenuating neuronal hyper-excitability of excitatory neurons in the BLA. [ABSTRACT FROM AUTHOR]

Introduction: Sunitinib is approved in China for treatment of gastrointestinal stromal tumors (GIST), after disease progression on, or intolerance to, imatinib. However, available data from prospective clinical trials on its efficacy and safety in Chinese patients is limited. Our objective is to determine the efficacy and safety of sunitinib in Chinese patients with imatinib-resistant/intolerant GIST. Methods: An open-label, single-arm, multicenter, phase IV study was performed in Chinese patients with imatinib-resistant/intolerant GIST. Sunitinib was administered orally in 6-week cycles of 4 weeks on-treatment (50 mg once daily) and 2 weeks off-treatment. The primary endpoint was progression-free survival (PFS). Tumors were assessed every 6 weeks for the first 24 weeks and every 12 weeks thereafter. Responses were evaluated according to Response Evaluation Criteria in Solid Tumors (RECIST) version 1.0. Results: A total of 60 patients were enrolled, of whom 59 were treated with sunitinib. All patients were Asian, and mean age was 55.1 years. Median PFS was 46.4 weeks (95% CI 33.6-53.1). An objective response (complete or partial) was observed in 11/58 (19%) patients. Median overall survival was 111.3 weeks (95% CI 75.4-167.1), median time to tumor progression was 47.3 weeks (95% CI 34.1-59.3), and median time to tumor response was 22.6 weeks (95% CI 10.4-57.3). The most common adverse events included leukopenia, fatigue, hand-foot syndrome, and neutropenia. No new safety concerns were identified. Conclusions: This study confirms that sunitinib is active and well tolerated in Chinese patients with imatinib-resistant/intolerant GIST. ClinicalTrials.gov identifier: NCT00793871. Funding: Pfizer Inc, USA. [ABSTRACT FROM AUTHOR]

Host immunity and tumor microenvironment significantly influence follicular lymphoma (FL) outcomes. Lymphopenia has been identified as a negative prognostic factor for FL. However, there is limited data regarding prognostic value of peripheral blood T lymphocyte subsets, especially absolute CD4 T cell counts (ACD4C) in FL. We studied 127 consecutive FL patients to investigate whether peripheral blood ACD4C or absolute monocytes (AMC) at diagnosis had an impact on FL prognosis. In our cohort, both low ACD4C and high AMC were the parameters associated with inferior progression-free survival (PFS) ( P = 0.021 and P = 0.013, respectively) and inferior overall survival (OS) ( P = 0.020 and P = 0.005, respectively) by univariate analysis. Multivariate analysis revealed that only low ACD4C was statistically significant in worse PFS (hazard ratio, 2.811; 95 % confidence interval, 1.137−6.950; P = 0.025) and shorter OS (hazard ratio, 3.393; 95 % confidence interval, 1.037−11.105; P = 0.043) independent of FLIPI-2. Evaluation of blood ACD4C could be a useful indicator of outcome in previously untreated FL patients. [ABSTRACT FROM AUTHOR]

The memristive behavior of AlO-based device is significantly improved by introducing Ag nanoparticles (NPs). Inserting Ag NPs can effectively reduce the switching voltages, increase the resistance ratio (about 10) and enhance the sweep endurance (300 cycles). In particular, the stable switching properties are obtained by inserting an Ag NPs layer with an average diameter of 14 nm on the surface of bottom electrode, and the devices show a long retention time (more than 10 s) compared with the devices without Ag NPs. The switching mechanism is related to the oxygen-vacancy-based conducting filaments and the interfacial effect. The local enhancement and nonuniform distribution of electric field have the benefits to promote, induce and modulate the growth of conducting filaments, such as shape, location and orientation, which are responsible for the improvement performance of the devices. [ABSTRACT FROM AUTHOR]

The Original article is published with an error in Table. [ABSTRACT FROM AUTHOR]

The excellent memristive behavior of ZnO-based devices with embedded Ti nano-layers is obtained. The results show that inserting Ti layers can effectively reduce the switching voltages and increase the R/ R ratio (more than 10). In particular, the stable switching properties is obtained by introducing 2.5 nm Ti layer, and the devices show good sweep endurance (about 320 cycles) and a long retention time of more than 10s as compared with the devices without Ti layer. A model combining the redox reaction and the oxygen vacancy-based conducting filament is proposed to explain the memory effect. The conducting filament will be formed and ruptured along fixed paths at a certain region due to the non-uniform distribution of oxygen vacancies, which is responsible for the improvement of device performance. [ABSTRACT FROM AUTHOR]

Highly sensitive detection of proteins offers the possibility of early and rapid diagnosis of various diseases. Microchip-based immunoassay integrates the benefits from both immunoassays (high specificity of target sample) and microfluidics (fast analysis and low sample consumption). However, direct capture of proteins on bare microchannel surface suffers from low sensitivity due to the low capacity of microsystem. In this study, we demonstrated a microchip-based heterogeneous immunoassay using functionalized SiO nanoparticles which were covalently assembled on the surface of microchannels via a liquid-phase deposition technique. The formation of covalent bonds between SiO nanoparticles and polydimethylsiloxane substrate offered sufficient stability of the microfluidic surface, and furthermore, substantially enhanced the protein capturing capability, mainly due to the increased surface-area-to-volume ratio. IgG antigen and FITC-labeled anti-IgG antibody conjugates were adopted to compare protein-enrichment effect, and the fluorescence signals were increased by ∼75-fold after introduction of functionalized SiO nanoparticles film. Finally, a proof-of-concept experiment was performed by highly efficient capture and detection of inactivated H1N1 influenza virus using a microfluidic chip comprising highly ordered SiO nanoparticles coated micropillars array. The detection limit of H1N1 virus antigen was 0.5 ng mL, with a linear range from 20 to 1,000 ng mL and mean coefficient of variance of 4.71 %. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A theoretical approach for predicting the attenuation of microwave propagation in sandstorms is presented, with electric charges generated on the sand grains taken into account. It is found that the effect of electric charges distributed partially on the sand surface is notable. The calculated attenuation is in good agreement with that measured in certain conditions. The distribution of electric charges on the surface of sand grains, which is not easy to measure, can be approximately determined by measuring the attenuation value of electromagnetic waves. Some effects of sand radius, dielectric permittivity, frequency of electromagnetic wave, and visibility of sandstorms on the attenuation are also discussed quantitatively. Finally, a new electric parameter is introduced to describe the roles of scattering, absorption and effect of charges in attenuation. [ABSTRACT FROM AUTHOR]

A new multi-functional iniferter with photo-induced and thermal dissociation group in one molecule, diethyl 2,3-dicyano-2,3-di(p- N,N-diethyldithiocarbamylmethyl)phenylsuccinate(DDDCS), was successfully synthesized. The bulk polymerizations of styrene (St) with DDDCS were studied. The initiation can take place either under UV light irradiation by the reversible C-S bonds dissociation of DDDCS or under heating by the reversible hexa-substituted C-C bond thermally dissociation. The polymerizations have "living" polymerization characteristics under both cases, i.e., the yield and the molecular weight of the resulting polymer increased linearly with increasing reaction time, and the resultant polymers can act as macroiniferter for preparing block copolymer. [ABSTRACT FROM AUTHOR]

The etching effects of hydrogen plasma for semiconductor materials including single crystalline silicon, polycrystalline silicon, silicon dioxide, and aluminum in plasma immersion ion implantation (PHI) doping experiments have been investigated. Etching can alter device structure and affect implant profile and dose. The effects of varying different PIII process parameters such as pulse potential, pulse repetition frequency, and substrate temperature are presented. The experimental data show that the spontaneous etching by hydrogen radicals enhanced by ion bombardment is responsible for the etching phenomena that occurs at the material surface. A model is used to calculate the retained implant dose and impurity profile when the etching effect is considered. [ABSTRACT FROM AUTHOR]

Silicon devices including diodes, metal oxide semiconductor capacitors, and p-channel metal oxide semiconductor transistors were fabricated by plasma immersion ion implantation (PHI) doping technique using a microwave multipolar bucket plasma system. BH diluted in helium (1%) was used as the gas source. The contamination by helium, hydrogen, iron, sodium, and aluminum impurities was evaluated by secondary ion mass spectrometry measurements. During PHI processing in an aluminum chamber with a stainless steel wafer holder, no aluminum and a dose of 4.1 x 10/cm of Fe were detected. Most of Fe ions were shielded by a thin layer of SiO during the device fabrications. Good quality devices have been demonstrated including low reverse current of 15 nA/cm (V = -5 V) in diodes and reasonable lifetimes of the minority carriers such as t = 55.0 µsec and = τ 54.2 µsec. [ABSTRACT FROM AUTHOR]