Resistive Memristors Using Robust Electropolymerized Porous Organic Polymer Films as Switchable Materials.

Porous organic polymers (POPs) with inherent porosity, tunable pore environment, and semiconductive property are ideally suitable for application in various advanced semiconductor-related devices. However, owing to the lack of processability, POPs are usually prepared in powder forms, which limits their application in advanced devices. Herein, we demonstrate an example of information storage application of POPs with film form prepared by an electrochemical method. The growth process of the electropolymerized films in accordance with the Volmer-Weber model was proposed by observation of atomic force microscopy. Given the mechanism of the electron transfer system, we verified and mainly emphasized the importance of porosity and interfacial properties of porous polymer films for memristor. As expected, the as-fabricated memristors exhibit good performance on low turn-on voltage (0.65 ± 0.10 V), reliable data storage, and high on/off current ratio (104). This work offers inspiration for applying POPs in the form of electropolymerized films in various advanced semiconductor-related devices.

Electrochemical Preparation of Porous Organic Polymer Films for High-Performance Memristors.

Porous organic polymer films (PFs) with intrinsical porosity and tuneable pore environment are ideally suited for application in electronic devices. However, the huge challenges still exist for construction of electronic devices based on PFs owing to lack of robustness, processability, and controllable preparation. Herein, we report the electrochemical preparation of carbazole-based porous organic polymer films (eCPFs) as switchable materials for the memristors. These eCPFs possess the characteristics of controllable thickness/size, high stability, and excellent porosity. Carbazole and cyano groups are introduced into the eCPFs to constructing electron transfer systems. Thus, the memristors constructed based on these eCPFs exhibit excellent switching performance, reliability, and reproducibility. The electrochemically controllable preparation method of porous organic polymer membranes proposed in this paper provides a feasible idea for the developments of electronic devices.

Porous organic polymers for electrocatalysis.

Porous organic polymers (POPs) composed of organic building units linked via covalent bonds are a class of lightweight porous network materials with high surface areas, tuneable pores, and designable components and structures. Owing to their well-preserved characteristics in terms of structure and composition, POPs applied as electrocatalysts have shown promising activity and achieved considerable advances in numerous electrocatalytic reactions, including the hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction, CO2 reduction reaction, N2 reduction reaction, nitrate/nitrite reduction reaction, nitrobenzene reduction reaction, hydrogen oxidation reaction, and benzyl alcohol oxidation reaction. Herein, we present a systematic overview of recent advances in the applications of POPs in these electrocatalytic reactions. The synthesis strategies, specific active sites, and catalytic mechanisms of POPs are summarized in this review. The fundamental principles of some electrocatalytic reactions are also concluded. We further discuss the current challenges of and perspectives on POPs for electrocatalytic applications. Meanwhile, the possible future directions are highlighted to afford guidelines for the development of efficient POP electrocatalysts.

In-situelectrochemical polymerization of aniline on flexible conductive substrates for supercapacitors and non-enzymatic ascorbic acid sensors.

Polyaniline, as a kind of conductive polymer with commercial application prospects, is still under researches in its synthesis and applications. In this work, polyaniline was fabricated on flexible substrates including carbon cloths and polyethylene naphthalate byin situelectropolymerization method. The synthesized flexible electrodes were characterized by scanning electron microscopy, High resolution transmission electron microscope, atomic force microscope, Fourier transform infrared, x-ray diffraction, and x-ray photoelectron spectroscopy. Owing to the conductivity and the reversible redox property, the polyaniline/carbon cloth electrodes show excellent properties such as decent supercapacitor performance and good detection capability toward ascorbic acid. As supercapacitors, the electrodes exhibit a specific capacitance as high as 776 F g-1at a current density of 1 A g-1and a long cycle life of 20 000 times in the three-electrode system. As ascorbic acid sensors, the flexible electrodes demonstrate stable response to ascorbic acid in the range of 1-3000µM with an outstanding sensitivity (4228µA mM-1cm-2), low detection limit (1µM), and a fast response time. This work holds promise for high-performance and low-cost flexible electrodes for both supercapacitors and non-enzymatic ascorbic acid sensors, and may inspire inventions of self-powered electrochemical sensor.

TRAIL inhibits HBV replication and expression by down-regulating liver-enriched transcription factors.

BACKGROUND AND STUDY AIMS: To investigate the role of low-concentration TRAIL on HBV replication and expression. MATERIAL AND METHODS: MTT assay was performed to determine the minimum concentrations of TRAIL protein in HepG2 cell apoptosis. HepG2 cells were transfected by HBV replication plasmid pHBV4.1. After the treatment with low concentration of TRAIL, the culture supernatant was collected to detect HBsAg and HBeAg by ELISA. Proteins were extracted from the resulted cells, followed by total RNA and HBV DNA intermediate replication. Southern Blot and Northern Blot were carried out to detect HBV RNA and HBV DNA replication intermediates, respectively. RT-PCR and Western Blot were carried out to detect gene and protein expressions for HNF4α, PPARα, and RXRα, respectively. RESULTS: 50 ng/ml of TRAIL protein led to significant decline on the secretions of HBsAg and HBeAg. Expression levels of HBV RNA and HBV DNA replication intermediates were significantly decreased too. In addition, gene and protein expressions of HNF4α, PPARα and RXRα also dropped, especially for PPARα whose expressions significantly decreased. CONCLUSION: TRAIL could inhibit HBV replication and expression by downregulating the expressions of liver-enriched transcription factors HNF4α, PPARα, and RXRα.

Flotation dynamics of metal and non-metal components in waste printed circuit boards.

Flotation is an effective and clean separation technology to realize the recovery of metal in waste printed circuit boards (WPCBs). The flotation kinetic of metal and non-metal components was concerned in this study. In addition, the loading of bubbles, the collision and shedding of particles and bubbles were used to assist in proving the particle dynamics results. By analyzing the force on the particles, the load of bubbles on particles was analyzed, and the appropriate volume ratio of bubbles to particles was 1.5-8.0, depending on the particle density. Moreover, Clift model and Schiller-Naumann model has high fitting accuracy for the final bubble velocity. In addition, metal particles have greater settling velocity, which results in shorter collision time with bubbles. In the process of bubble-particle rising, the shedding probability gradually decreases, and the shedding probability of metal particles is much higher than that of non-metal particles. The results of flotation kinetics show that the removal of impurity particles represented by silicon mainly occurs in the initial stage of flotation process. The loss of copper increases with flotation time and collector dosage. This study reveals the flotation kinetics of particles from the perspectives of bubble loading, bubble-particle collision and shedding.

[The Application of Estrogen Receptor Aptamer in Immunohistochemical Detection of Breast Cancer].

OBJECTIVE: To synthesize and select an estrogen receptors aptamer that can be used in immunostaining of breast cancer tissues. METHODS: ER protein was purified. ER aptamer that showed a high affinity and specificity for ER was synthesized and selected and by SELEX. Ligand -receptor interactions assay was adopted to measure the affinity of the aptamer-ER complex. Both the biotinylated aptamer and the anti-ER monoclonal antibody were tested for immunohistochemical staining of ER status on 105 breast cancer samples. Agreement on the detection of ER expression was determined by Kappa statistics. RESULTS: The dissociation contant (Kd) of the biotinylated aptamer-ER complex, as calculated by a linear regression analysis, was determined to be (0.34±0.05) nmol/L ( n=3, r=0.989). The binding capacity (B max) was 769.23 fmol/(mg prot·nmol -1·L -1). The ER aptamer and the anti-ER antibody both exhibited identical specificity to ER-expressing breast cancer cells. There was a high agreement between the two methods ( n=105, Kappa value=0.943, 95% confident interval=0.879-1.006, P<0.05 for the ER positive and negtive samples; n=75, Kappa value=0.805, 95% confident interval=0.642-0.967, P<0.05 for the ER weak and moderate/strong expression samples). Both the anti-ER antibody and the ER aptamer can also recognized breast cancer cells at the same sites. There was no expression in the negative controls. There were also positive expressions in the 2 endometrial cancer tissues by using biotinylated aptamer. CONCLUSIONS: Our results indicated that the synthesized ER aptamer has a high affinity to bind ER. ER aptamer and the anti-ER antibody can both be used for immunohistochemical staining of ER status in breast cancer tissue.

A nickel foam modified with electrodeposited cobalt and phosphor for amperometric determination of dopamine.

Considering the importance of dopamine (DA) detection for neuroscience and disease diagnosis, herein, an electrochemical sensor for dopamine is described. It is based on the use of a Ni-Co-P nanostructure fabricated on nickel foam via electrode position from cobalt chloride and ammonium phosphate for 10 min. Time-dependent experiments show the transformation of Ni-Co-P nanoparticles to spheres. The resulting electrode display excellent electrochemical response to DA. Figures of merit include (a) a working potential of 0.55 V (vs. Ag/AgCl); (b) an electrochemical sensitivity of 5262 µA mM-1 cm-2; (c) a wide linear range (from 0.5 to 2350 µM), and (d) a 1 µM detection limit. The outstanding electrochemical performance is explained by the synergistic effects of large surface area, improved electron transfer, presence of free binders, and the presence of three active components (nickel, cobalt and phosphonium ion). Graphical abstract A Ni-Co-P nanostructure was electrodeposited on nickel foam to obtain an electrochemical sensor for amperometric determination of dopamine with outstanding performance.

Drainage versus No Drainage after Laparoscopic Cholecystectomy for Acute Cholecystitis: A Meta-Analysis.

To conduct a randomized controlled trial (RCT), meta-analysis to assess the effectiveness of drains in reducing complications after laparoscopic cholecystectomy (LC) for acute cholecystitis needs to be carried out. An electronic search of PubMed, Embase, Science Citation Index, and the Cochrane Library from January 1990 to January 2018 was performed to identify randomized clinical trials that compare prophylactic drainage with no drainage in LC for acute cholecystitis. The outcomes were calculated as odds ratios (ORs) with 95 per cent confidence intervals (CIs) using RevMan 5.2. Four RCTs, which included 796 patients, were identified for analysis in our study. There was no statistically significant difference in the rate of morbidities (OR = 1.23, 95% CI 0.55-2.76, P = 0.61). Abdominal pain was more severe in the drain group 24 hours after surgery (mean difference = 0.80, 95% CI 0.47-1.14; P < 0.00001). No significant difference was present with respect to wound infection rate and hospital stay. The use of abdominal drainage does not appear to be of any benefit in patients having undergone early LC for acute cholecystitis.

Insight into the role of TRAIL in liver diseases.

TNF-related apoptosis inducing ligand (TRAIL) is a potential antitumor protein known for its ability to selectively eliminate various types of tumor cells without exerting toxic effects in normal cells and tissues. TRAIL has recently been suggested as a potential therapeutic target in hepatocellular carcinoma (HCC) because it promotes apoptosis in cancer cells. Furthermore, studies on the role of TRAIL in liver injury have reported that TRAIL plays an essential role in viral hepatitis, fatty liver diseases, etc. However, several contradictory and confounding effects of TRAIL in these liver diseases have not been fully elucidated or placed into perspective. Hence, this review summarizes recent progress in studies on TRAIL, including its role in apoptotic signaling, potential therapeutic applications of TRAIL in HCC, hepatitis virus infection, and liver fibrosis and cirrhosis.

Performance of serum HBcrAg in chronic hepatitis B patients with 8-year nucleos(t)ide analogs therapy.

AIM: This study aimed to investigate long-term kinetics of serum hepatitis B core-related antigen (HBcrAg) and its correlation with serum hepatitis B surface antigen (HBsAg) in a real-world cohort of patients who had received over 8 years of nucleos(t)ide analogs(NAs) therapy. METHODS: This was a retrospective study. All patients were recruited from our previous published study, who started therapy with NAs between 2007 and 2008. Serum HBcrAg and HBsAg levels were quantitatively measured at baseline, the sixth month and each year of follow-up, using the stored serum samples. RESULTS: Among the 94 patients, serum HBcrAg presented a gradually decreasing trend from baseline to year 8, either in HBeAg-negative or HBeAg-positive patients. After 8 years of NAs treatment, 21.3% of patients achieved serum HBcrAg < 3 log 10 U/mL, and only baseline HBcrAg was an independent predictor. Additionally, good correlation of HBcrAg and HBsAg was observed at baseline, but this correlation weakened remarkably during treatment. CONCLUSION: Serum HBcrAg is decreasing gradually with the duration of antiviral therapy, and baseline HBcrAg level is an independent predictor of long-term HBcrAg below the limit of detection.

Pronounced decline of serum HBsAg in chronic hepatitis B patients with long-term effective nucleos(t)ide analogs therapy.

AIMS: This study aims to investigate the kinetics of serum HBsAg levels in chronic hepatitis B patients with long-term nucleos(t)ide analogs (NAs) therapy. METHODS: This was a retrospective clinical study. Serum HBsAg in serial samples of 94 patients, who received at least 8 years of NAs therapy, were measured using Elecsys® HBsAg II Quant Assay. RESULTS: In this cohort, serum HBsAg levels reduced from 3.80 log10 IU/mL at baseline to 2.72 log10 IU/mL at year 8 (p < .001), and the percentage of patients with HBsAg <1000 IU/mL increased from 14.9% at baseline to 55.3% at year 8 (p < .001). The reduction of serum HBsAg did not differ significantly between patients stratified by baseline virological parameters and type of antiviral agents. But as compared to patients without HBeAg seroconversion, HBsAg levels were significant lower in patients with HBeAg seroconversion (3.19 vs. 2.47 log10 IU/mL at year 8, p = .001). As compared to patients with slow (0-1 log10 IU/mL) or steady HBsAg(≤0 log10 IU/mL) decline at year 1, patients with a rapid HBsAg (≥1 log10 IU/mL) decline had a significantly lower HBsAg levels from year 2 to 8. However, Cox regression analysis showed that only absolute HBsAg levels at year 1 was an independent predictor of subsequent HBsAg <1000 IU/mL at year 8 of antiviral therapy(HR 0.242, p = .004). CONCLUSION: Pronounced HBsAg declines could be achieved in patients after long-term effective therapy with NAs, and on-treatment low serum HBsAg level at year 1 might be a predictor of serum HBsAg <1000 IU/mL at year 8.

Visible light nonlinear absorption and optical limiting of ultrathin ZrSe3 nanoflakes.

The nonlinear absorption and nonlinear refractive properties of ZrSe3 nanoflakes were studied with a 6.5 ns pulse laser at 532 nm. Open-aperture Z-scan curves reveal that ZrSe3 nanoflakes have a strong reverse saturable absorption property, and close-aperture Z-scan curves show that ZrSe3 dispersions possess a positive nonlinear refractive index caused by self-focusing. The nonlinear absorption coefficient, the nonlinear refraction coefficient, and the figures of merit (FOM) of ZrSe3 dispersed in water with linear transmittances of 0.86 at input energy of 18 µJ are 6.35 × 10-10 m W-1 15.73 × 10-17 m2 W-1, and 10.09 × 10-11 esu · cm respectively. In addition, nonlinear optical (NLO) performance of ZrSe3 nanoflakes depends on organic solvent dispersions. ZrSe3 nanoflakes in water dispersions have the largest FOM of 10.27 × 10-11 esu · cm, while the FOM in ethanol dispersions is 5.41 × 10-11 esu · cm at the same input energy of 26.5 µJ. The optical limiting threshold Fth of ZrSe3 nanosheet is 2.2 J cm-2 under picosecond laser pulse. The Results imply that ZrSe3 nanoflakes are an extraordinarily promising material for novel nanophotonic devices like optical limiters.

Reverse saturable absorption and nonlinear refraction of ultrathin ZrS3 nanobelts.

The nonlinear optical (NLO) properties of a ZrS3 nanobelt were measured with a 6.5 ns pulse laser at 532 nm. Its optical response to the incident light exhibits good optical absorptive and refractive effects, with the nonlinear absorption coefficient ß = 4.42 × 10(-10) m W(-1) and the nonlinear refraction coefficient γ = 5.86 × 10(-17) m(2) W(-1) for the ZrS3 nanobelt in ethanol dispersions at an input energy of 34.25 µJ. In addition, the ß values and γ values have dependence on input energy. Results show that the ZrS3 nanobelts have an excellent reverse saturable absorption (RSA) performance in nanosecond pulses, demonstrating that ZrS3 nanobelts are an extraordinarily promising novel optical power limiting material. Meanwhile, compared to the pure ZrS3, graphene oxide (GO) and reduced graphene oxide (RGO), composites (ZrS3/GRO) exhibit an enhanced nonlinear absorption response at the same input energy.

Role of RANKL in the regulation of NFATc1 and c­Src mRNA expression in osteoclast­like cells.

This study was designed to determine the effects of receptor activator of nuclear factor κB ligand (RANKL) on the mRNA expression of nuclear factor of activated T-cells, cytoplasmic, calcineurin-dependent 1 (NFATc1) and c­Src in rat osteoclast­like cells. The marrow cells were exposed to macrophage colony-stimulating factor (M­CSF; 25 ng/ml) and different concentrations of RANKL (0, 50, 75 and 100 ng/ml) for 9 days. The mRNA expression of NFATc1 and c­Src was determined by polymerase chain reaction. Compared with the M­CSF (25 ng/ml)+RANKL (0 ng/ml) group, the levels of NFATc1 and c­Src mRNA expression were significantly increased in the M­CSF (25 ng/ml)+RANKL (75 and 100 ng/ml) groups (P<0.01, P<0.01, P<0.01 and P<0.01, respectively). Compared with the M­CSF (25 ng/ml)+RANKL (50 ng/ml) group, the levels of NFATc1 and c­Src mRNA expression was significantly increased in the M­CSF (25 ng/ml)+RANKL (75 and 100 ng/ml) groups (P<0.05, P<0.01, P<0.01 and P<0.01, respectively). Compared with M­CSF (25 ng/ml)+RANKL (75 ng/ml) group, the levels of NFATc1 and c­Src mRNA expression was significantly increased in the M­CSF (25 ng/ml)+RANKL (100 ng/ml) group, (P<0.01 and P<0.01, respectively). These data suggest that RANKL could regulate the expression of NFATc1 and c­Src mRNA in the marrow culture system.

The Function of Naringin in Inducing Secretion of Osteoprotegerin and Inhibiting Formation of Osteoclasts.

Osteoporosis has become one of the most prevalent and costly diseases in the world. It is a metabolic disease characterized by reduction in bone mass due to an imbalance between bone formation and resorption. Osteoporosis causes fractures, prolongs bone healing, and impedes osseointegration of dental implants. Its pathological features include osteopenia, degradation of bone tissue microstructure, and increase of bone fragility. In traditional Chinese medicine, the herb Rhizoma Drynariae has been commonly used to treat osteoporosis and bone nonunion. However, the precise underlying mechanism is as yet unclear. Osteoprotegerin is a cytokine receptor shown to play an important role in osteoblast differentiation and bone formation. Hence, activators and ligands of osteoprotegerin are promising drug targets and have been the focus of studies on the development of therapeutics against osteoporosis. In the current study, we found that naringin could synergistically enhance the action of 1α,25-dihydroxyvitamin D3 in promoting the secretion of osteoprotegerin by osteoblasts in vitro. In addition, naringin can also influence the generation of osteoclasts and subsequently bone loss during organ culture. In conclusion, this study provides evidence that natural compounds such as naringin have the potential to be used as alternative medicines for the prevention and treatment of osteolysis.

The Serum Anti-HBs Level Among Children Who Received Routine Hepatitis B Vaccination During Infancy in Mianyang City, China: A Cross-Sectional Study.

Hepatitis B virus (HBV) prevalence has declined remarkably in children due to nationwide universal vaccination program for HBV in China. However, the persistence of immune response against HBV infection and the optimal time point when a booster vaccination should be performed remain to be elucidated. To assess the persistence and level of antibody against hepatitis B surface antigen (anti-HBs) in a representative population of age 15 and younger who received routine hepatitis B vaccination in Mianyang City, China. A cross-sectional study was conducted in 2011. One thousand five hundred twenty-six children of age 15 and younger who received three doses of 5 µg hepatitis B vaccine series during infancy but did not receive a booster vaccination later were enrolled. Of the 1,526 children, the mean age was 8.2 ± 4.1 and 739 children were male. The median anti-HBs level was 23.0 mIU/mL, and the total percentage of anti-HBs levels ≥10 mIU/mL was 60.9%. With an increase of age, median anti-HBs level, percentage of anti-HBs levels ≥10 mIU/mL, and percentage of anti-HBs levels ≥100 mIU/mL declined remarkably in the early period and reached the lowest level at the age of 3 and then remained relatively stable. The median anti-HBs level, the percentage of anti-HBs levels ≥10 mIU/mL, and the percentage of anti-HBs levels ≥100 mIU/mL in 1- and 2-year-old children were much higher than that in children aged 3-15 (p < 0.05, respectively). Immunity against HBV infection gradually decreased in early ages of children of 15 and younger who received three doses of 5 µg hepatitis B vaccine series during infancy in China. Three dosages of 10 µg hepatitis B vaccine for infants and repeated vaccination or additional booster vaccination for some children at or before age 3 should be provided to get much more powerful immunity to HBV.

Sustained suppression of viral replication in improving vitamin D serum concentrations in patients with chronic hepatitis B.

Recently, the role of vitamin D in chronic hepatitis B (CHB) has attracted a lot attention. In this study, 128 naïve CHB patients (91 with positive HBeAg, 37 with negative-HBeAg) were enrolled, and 128 volunteers without liver diseases were enrolled as controls. Compared to that of healthy controls, the mean level of 25(OH)D3 in CHB patients was significantly lower; and the percent of patients with sufficient 25(OH)D3 (≥20 ng/mL) was also significantly lower than that of healthy controls. Among those CHB patients, the level of 25(OH)D3 was negatively correlated with the serum HBV-DNA level. Additionally, the level of 25(OH)D3 was significantly lower in HBeAg-positive patients than that in HBeAg-negative patients. After the patients went through the long-term antiviral treatments, both the mean level of 25(OH)D3 and the percent of patients with sufficient 25(OH)D3 increased significantly. Additionally, patients who were HBeAg free after the treatment also had much higher 25(OH)D3 level than those with persistent positive HBeAg. All those data suggested that the low vitamin D serum level was dangerous for CHB patients, and the level of 25(OH)D3 was highly negatively correlated with HBV-DNA levels. Effective antiviral therapy might increase the level of vitamin D in CHB patients.

Enhanced ultraviolet-visible light responses of phototransistors based on single and a few ZrS3 nanobelts.

Phototransistors based on single and three ZrS3 nanobelts were fabricated on SiO2/Si wafers by photolithography and the lift-off technique, respectively, and their light-induced electric properties were investigated in detail. Both the devices demonstrate a remarkable photoresponse from ultraviolet to near infrared light. The photoswitch current ratio (PCR) of the single-nanobelt phototransistor is 13 under the illumination of 405 nm light with an optical power of 10.5 mW cm(-2) at a bias of 5 V, while the PCR of the three-nanobelt device is 210 under the illumination of 405 nm light with an optical power of 5.57 mW cm(-2) at a bias of 1 V. On comparison of the photoresponses under the same conditions, the latter is found to be superior to the former, and both the devices show a much better photoresponse than the reported flexible ZrS3-nanobelt-film photodetector.

Association of the miRNA146a rs2910164 C>G Polymorphism with Head and Neck Cancer Risk: A Meta-analysis.

OBJECTIVE: To investigate any association of the miRNA146a rs2910164 C>G polymorphism with head and neck cancer risk. MATERIALS AND METHODS: The Medline, PubMed, PUBMED, EMBASE, Web of Science, WanFang and CNKI databases were searched and a meta-analysis was conducted using RevMan 5.2 software. RESULTS: After searching and evaluating the literature, a total seven papers involving 2,766 patients with head and neck cancer and 6,603 healthy controls were included into this meta analysis. The results showed that there were no significant differences between patients and healthy controls overall for the miRNA rs2910164 C>G gene polymorphism (dominant model:OR=0.78, 95%CI:0.58-1.04, P=0.09; recessive model:OR=0.86, 95%CI:0.67-1.12, P=0.27;GG:CC:OR=0.75, 95%CI:0.52-1.08, P=0.12;GC:CC:OR=0.79, 95%CI:0.60-1.04, P=0.10). However, a significant association of miRNA rs2910164 C>G gene polymorphism with Chinese head and neck cancer risk was noted, limited to the dominant model (OR=0.68, 95%CI:0.50-0.95, P=0.02;GG:CC:OR=0.62, 95%CI:0.42-0.92, P=0.02;GC:CC:OR=0.72, 95%CI:0.520.99, P=0.04). CONCLUSIONS: miRNA146a rs2910164 C>G polymorphism is not associated with head and neck cancer risk in general, but tehre may be link in Chinese.