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Black phosphorus (BP) is an emerging two-dimensional semiconductor material, which has interesting structural features and broad application prospects in the fields of optoelectronic devices, energy storage, and biomedicine. However, a large amount of evidence is still needed to clarify the potential mechanism for the synthesis of high-quality BP crystals in chemical vapor transport (CVT) reactions. In this work, High-purity BP crystal was synthesized by CVT method in amorphous Red Phosphorus (aRP), Sn and I2 system. We found that the synthesis of BP experienced three stages of structural transformation of aRP-P4-Hittorf’s Phosphorus (HP)-BP. First, the phase transition of aRP and P4 molecules was reversible in the sublimation stage; then, the P4 molecules were gradually transformed into the HP structure in the transportation and deposition stage; however, the nucleation of BP quickly inhibited the growth of HP and completed the phase transition quickly; Finally, the remaining P4 molecules were transformed into BP structure, which promoted the growth of BP crystals. This crystallization kinetics explained the nucleation mechanism during the formation of BP, and the competitive nucleation between HP and BP provided the possibility for the bottom-up preparation of BP nanobelts.

Immobilization of single metal atoms on a solid host opens numerous possibilities for catalyst designs. If that host is a two-dimensional sheet, sheet curvature becomes a design parameter potentially complementary to host and metal composition. Here, we use a combination of density functional theory calculations and microkinetic modeling to compare the mechanisms and kinetics of formic acid decomposition and formation, chosen for their relevance as a potential hydrogen storage medium, over single Ru atoms anchored to pyridinic nitrogen in a planar graphene flake (RuN4-G) and curved carbon nanotube (RuN4-CNT). Activation barriers are lowered and the predicted turnover frequencies are increased over RuN4-CNT relative to RuN4-CNT. The results highlight the potential of curvature control as a means to achieve high performance and robust catalysts.

Ammonia oxidation is the heart of the Ostwald process and is important in emissions control. Catalytic behaviors are a function of conditions and are observed to vary across the platinum group metals (PGMs) Pt, Pd, Rh. Here, we combine density functional theory computations and microkinetic modeling to rationalize these dependencies. We compute reactions over model (2 1 1) and (1 1 1) surfaces of PGMs. Binding energies are similar on Pd and Pt and generally greater on Rh, while activation energies vary across all metals. Rates on (2 1 1) surfaces are greater than (1 1 1) surfaces. The stepped Pt is most active and stepped Rh most selective to N2 at ammonia slip conditions, while at Ostwald process conditions, stepped Pd is most active and stepped Pt most selective to NO. Degree of rate and selectivity control analysis provides insights into the reactions limiting performance of PGMs. Both activation barriers and surface coverages influence rates and selectivities.

ContainsZACROS input files and python scripts for postprocessing simulation outputs.&nbsp

Cervical cancer is the fourth most common malignant tumor in women worldwide. The persistent infection of high-risk Human Papillomavirus (hrHPV) is considered to be the primary cause of this disease. As an innate immune receptor, the nucleotide-binding oligomerization domain protein-1 (NOD1) recognizes the pathogen-associated molecular pattern (PAMP), subsequently initiating immune responses. NOD1 is also involved in the apoptotic signaling pathway and mutates in many cancer cells. In the study, we revealed that NOD1 expression decreased during the progression of cervical intraepithelial neoplasia to cervical cancer and that HPV16 E6/E7 oncoproteins induced down-regulation of NOD1. Moreover, the activation of NOD1 promoted the apoptosis of HPV16-positive cervical cancer cells. The data indicated that the dysregulation of NOD1-mediated inflammation and apoptosis may contribute to cervical intraepithelial neoplasia progression and cervical cancer.

Pd-catalyzed reduction has emerged as a promising treatment strategy to remove the recalcitrant disinfection byproduct N-nitrosodimethylamine (NDMA). However, the reaction pathways remain unexplored, and questions remain about how water solvent influences NDMA reduction mechanisms and selectivity. Here, we compute the energies and barriers of all relevant elementary steps in NDMA reduction by H2 on Pd(111) using density functional theory. We further calculate water-assisted H-shuttling for all hydrogenation reactions explicitly and include water solvation for all elementary reactions implicitly. We parametrize microkinetic models to predict product formation rates and selectivities over a wide range of NDMA concentrations. We show that H2O-mediated H-shuttling lowers the reaction barriers for all hydrogenation reactions involved in NDMA reduction while implicit solvation has negligible impact on the reaction and activation energies. We further conduct batch experiments with SiO2-supported Pd nanoparticles and compare them with the microkinetic models. The predicted rates, selectivity, and apparent activation energy from the model parametrized with both explicit H2O-mediated H-shuttling and implicit solvation correspond well with experimental observations. Models that ignore water as an H-shuttle or solvent fail to recover the experimental rates and apparent activation energy. We identified the rate-determining steps of the reaction and show the reaction flow pathways of the complicated reaction network. Finally, we demonstrate that water-mediated H-shuttling changes the rate-determining steps and reaction flows of elementary reactions.

Heterogeneous catalysts coupled with non-thermal plasmas (NTP) are known to achieve reaction yields that exceed the contributions of the individual components. Rationalization of the enhancing potential of catalysts, however, remains challenging because the background contributions from NTP or catalysts are often non-negligible. Here, we first demonstrate platinum (Pt)-catalyzed nitrogen (N2) oxidation in a radio frequency plasma afterglow at conditions at which neither catalyst nor plasma alone produces significant concentrations of nitric oxide (NO). We then develop reactor models based on reduced NTP- and surface-microkinetic mechanisms to identify the features of each that lead to the synergy between NTP and Pt. At experimental conditions, NTP and thermal catalytic NO production are suppressed by radical reactions and high N2 dissociation barrier, respectively. Pt catalyzes NTP-generated radicals and vibrationally excited molecules to produce NO. The model construction further illustrates that the optimization of productivity and energy efficiency involves tuning of plasma species, catalysts properties, and the reactor configurations to couple plasma and catalysts. These results provide unambiguous evidence of synergism between plasma and catalyst, the origins of that synergy for N2 oxidation, and a modeling approach to guide material selection and system optimization., Heterogeneous catalysts coupled with non-thermal plasma are known to achieve higher reaction yields, but disentangling the gain achieved by the individual components remains challenging. Here, NO is produced from N2 and O2 in a plasma-catalytic reactor at conditions at which neither catalyst nor plasma alone is productive, providing unambiguous evidence of plasma-catalyst synergy.

Sensitive testing for Microcystins-LR (MC-LR) is needed because of its serious environmental and human health hazards. In this work, a new type of surface plasmon resonance (SPR) enhanced cathodic electrochemiluminescence (ECL) aptasensing platform was designed in which boron and nitrogen co-doped graphene quantum dots (BN-GQDs) were used as the luminary and bismuth nanoparticles (Bi NPs) were used as the SPR source. SPR effect of non-precious metal Bi NPs can induce and enhance ECL signal of BN-GQDs because the fluorescence spectrum of BN-GQDs overlaps well with the ultraviolet-visible absorption spectrum of Bi NPs. On this basis, a sensitive sensing system based on the Bi NPs and BN-GQDs was established for MC-LR detection. The results showed that the ECL sensing signal obtained was linear with the negative logarithm of the target MC-LR concentration in the range of 0.01-5000 pM, and the detection limit was 0.003 pM. In addition, the sensor had high stability and good reproducibility, which can be applied to the detection of MC-LR in actual samples. The method had good specificity and can not be disturbed by its homolog, which can be used for sensitive and reliable detection of complex samples.

Background: Most tumors have an enhanced glycolysis flux, even when oxygen is available, called the aerobic glycolysis or the Warburg effect. Metabolic reprogramming promotes cancer progression, and is even related to the tumorigenesis. However, it is not clear whether the observed metabolic changes act as a driver or a bystander in cancer development. Methods: In this study, the metabolic characteristics of oral precancerous cells and cervical precancerous lesions were analyzed by metabolomics, and the expression of glycolytic enzymes in cervical precancerous lesions was evaluated by RT-PCR and Western blot analysis. Results: In total, 115 and 23 metabolites with reliable signals were identified in oral cells and cervical tissues, respectively. Based on the metabolome, oral precancerous cell DOK could be clearly separated from normal human oral epithelial cells (HOEC) and oral cancer cells. Four critical differential metabolites (pyruvate, glutamine, methionine and lysine) were identified between DOK and HOEC. Metabolic profiles could clearly distinguish cervical precancerous lesions from normal cervical epithelium and cervical cancer. Compared with normal cervical epithelium, the glucose consumption and lactate production increased in cervical precancerous lesions. The expression of glycolytic enzymes LDHA, HK II and PKM2 showed an increased tendency in cervical precancerous lesions compared with normal cervical epithelium. Conclusions: Our findings suggest that cell metabolism may be reprogrammed at the early stage of tumorigenesis, implying the contribution of metabolic reprogramming to the development of tumor.

Ammonia oxidation is operated at different temperatures over Pt catalysts of different structures to recover different products. In this work, we elucidate the dependency of ammonia oxidation rates and selectivities on both Pt structure and temperature. We perform density functional theory (DFT) computations to compare the reaction and activation energies of elementary reactions on Pt(211) and Pt(111). We develop a microkinetic model parametrized with the DFT results. We show that barriers to product formation are lower on stepped Pt than on terrace, leading to a much higher step rate at low temperature to selectively oxidize ammonia to nitrogen. At high temperature, however, both step and terrace perform comparably in rate to selectively produce nitric oxide. While N2 is always the thermodynamic product, relative N and O coverages interact to make NO the kinetic product at high temperature. The predicted rate and selectivity are consistent with experiments. We further show rate-controlling steps on the t...

Both introducing oxygen vacancies (OVs) and enhancing charge transfer efficiency (CTE) have been proved to be effective strategies to improve the capability of the catalyst to activate peroxymonosulfate (PMS). The OVs on catalysts can promote the CTE of the catalyst/PMS oxidation system. However, current OVs introduction methods can only lead to very limited CTE enhancement. Here, the synthesis of CoP/CoOx heterostructured nanoparticles with abundant OVs and dramatically enhanced CTE through a reliable partial phosphidation method using ZIF-67 as a precursor was reported. The excellent CTE of the CoP/CoOx/PMS oxidation system was the result of the synergy of increased OVs and introduced CoP with high conductivity. When served as Fenton-like catalyst for tetracycline (TC) degradation via activating PMS, due to the synergy between abundant OVs and high CTE, CoP/CoOx exhibited superior performance for TC removal, with the pseudo-second-order kinetic rate constant ∼ 10.3 and 77.4 times that of CoPx and Co3O4, respectively. Moreover, the cobalt leakage (0.06 mg/L) was only about 1/2 and 1/3 of that of CoPx and Co3O4, respectively. The mechanism study suggested that SO4•−, •OH and O2•− played an important role in TC degradation. The excellent catalytic performance of CoP/CoOx was attributed to its abundant OVs and high CTE to generate more active oxygen species. This work provides new insights for designing and developing efficient catalysts for wastewater treatment via Fenton-like process.

The composite comprised of graphene and carbon nanotubes (CNTs) exhibited significantly enhanced electrochemical performance due both to the improved dispersion and inhibition of restacking of graphene and CNTs. In this work, graphene nanoribbons (GNRs)/CNTs composite (GNRs/CNTs) was synthesized on gram-scale by chemical vapor deposition. Under optimal growth conditions, the yield of GNRs/CNTs as high as 26 g per gram catalyst could be achieved in 30 min growth time. The morphology and quality of the as-synthesized composite was verified by using SEM, TEM and Raman spectroscopy. The electrochemical properties of GNRs/CNTs was evaluated using cyclic voltammetry (CV) and galvanostatic charge-discharge techniques. GNRs/CNTs exhibited specific capacitance of 242.3 F/g at 0.5 A g-1, which was over 4 times of that of CNTs. The GNRs/CNTs based electrodes exhibited excellent cycling stability at 1 A g-1 for over 4000 cycles, which can be attributed to the excellent electrical conductivity and the unique structure. When employed as electrode for membrane capacitive desalination, the desalination capacity of 16.46 mg g-1 has been achieved under 1.2 V with 500 mg L-1 NaCl solution as feeding water.

Objectives To evaluate the diagnostic values of urine liquid-based cytology (LBC), fluorescence in situ hybridization (FISH), and p16/Ki-67 dual immunostaining in the detection of upper tract urothelial carcinomas (UTUCs). Methods Sixty-one patients with UTUCs were retrospectively analyzed. All patients were diagnosed both by urine cytology and by FISH, and histologically confirmed as UTUCs. Thirty-two patients had been stained with p16/Ki-67 dual labeling. Results The sensitivities for low-grade UTUCs (LGUTUCs) and high-grade UTUCs (HGUTUCs) were 33.3% and 67.4% by LBC, 60% and 69.6% by FISH, and 12.5% and 66.7% by p16/Ki-67 dual labeling, respectively. Conclusions Our results indicated that LBC was more suitable to identify HGUTUCs, FISH was highly valuable for predicting LGUTUCs, and p16/Ki-67 dual labeling was useful for distinguishing HGUTUCs from LGUTUCs. The combined application of these methods may improve the sensitivity or accuracy in the detection or diagnosis of UTUCs.

Circular RNAs (circRNAs) are a novel group of noncoding RNAs characterized by a covalently closed loop. An increasing evidence suggests that deregulated circRNAs exert their essential regulatory roles in oncogenesis. However, little is explored on the biological role of novel circRNAs in cervical cancer (CC) progression. In the present study, we analyzed two GSE microarrays to screen for CC-specific circRNAs and found two circRNAs both expressed in CC cells and tissues. Among them, circ_0005576 was significantly overexpressed in both CC tissues and cell lines. Furthermore, upregulated circ_0005576 was positively associated with advanced FIGO stage, lymph node metastasis, but was negatively related with overall survival of CC patients. Additionally, circ_0005576 knockdown induced a suppressed cell growth, colony formation and metastasis of HeLa and SiHa cells. Mechanistically, circ 0005576 was mainly located in the cytoplasm and served as a sponge of miR-153-3p to increase kinesin family member 20A (KIF20A) expression. Rescue assays further validated the effects of circ_0005576/miR-153-3p/KIF20A axis on CC proliferation, migration and invasion. In conclusion, our research reveals a novel circ_0005576/miR-153-3p/KIF20A axis promoting CC progression, which may suggest a new insight into the pathogenesis of CC.

Heterogeneous catalysis is essential to industrial chemical processes, from those that transform petroleum into fuels and chemicals to those, like the Haber Bosch process, that create fertilizers to feed the planet. Catalysis science has revealed that the most common heterogeneous catalysts, which include the later members of the d block transition metals, present a tableau of reactivity limited by intrinsic correlations between the various reaction steps that make up a surface catalytic reaction. Coupling of heterogeneous catalysts with non-thermal plasmas offers the potential to break these constraints. While empirical evidence suggests that such combinations can enhance apparent catalytic function relative to plasmas or catalysts alone, the absence of basic models to rationalize this behavior and guide material and plasma selection has limited progress. In this talk I will describe our recent work to bridge this gap, focusing on nitrogen reduction (ammonia synthesis) and nitrogen oxidation (NO synthesis) as two different approaches to realize chemical transformations that are difficult or impossible to achieve through catalytic routes alone.

Graphene-supported uranium dioxide (UO2) nanocrystals are potentially important fuel materials. Here, we investigate the possibility of synthesizing graphene-supported UO2 nanocrystals in polar ethylene glycol compounds by the polyol reduction of uranyl acetylacetone under boiling reflux, thereby enabling the use of an inexpensive graphene precursor graphene oxide into a one-pot process. We show that triethylene glycol is the most suitable solvent with an appropriate reduction potential for producing nanometer-sized UO2 crystals compared to monoethylene glycol, diethylene glycol, and polyethylene glycol. Graphene-supported UO2 nanocrystals synthesized with triethylene glycol show evidence of heteroepitaxy, which can be beneficial for facilitating heat transfer in nuclear fuel particles. Furthermore, we show that graphene-supported UO2 nanocrystals synthesized by polyol reduction can be readily stored in alcohols, impeding oxidation from the prevalent oxygen in air. Together, these methods provide a facile approach for preparing and storing graphene-supported UO2 nanocrystals for further investigation and development under ambient conditions.

Estrogen signaling influences the development and progression of ovarian tumors, but the underlying mechanisms are not well understood. In a previous study we demonstrated that impairment of estrogen receptor alpha (ERα)-mediated olfactomedin 4 (OLFM4) expression promotes the malignant progression of endometrioid adenocarcinoma, and we identified OLFM4 as a potential target of miR-486-5p. In this study we investigated the role of OLFM4 in ovarian serous adenocarcinoma. Ovarian serous adenocarcinoma tissues had reduced OLFM4 expression. Expression of OLFM4 was positively correlated with ERα expression, and estrogen (E2) treatment in ovarian cancer cells induced OLFM4 expression in an ERα-dependent manner. In contrast to ERα, miR-486-5p levels were inversely correlated with OLFM4 expression in ovarian serous adenocarcinoma. Ovarian cancer cells transfected with miR-486-5p mimics showed decreased OLFM4 mRNA expression, and ovarian cancer cells treated with E2 showed reduced cellular miR-486-5p levels. OLFM4 knockdown enhanced proliferation, migration, and invasion by ovarian cancer cells. Low expression of OLFM4 was also associated with high tumor FIGO stage and poor tumor differentiation. These results suggest OLFM4 is downregulated by miR-486-5p, which contributes to ovarian cancer tumorigenesis. Conversely, estrogen receptor signaling downregulates miR-486-5p and upregulates OLFM4 expression, slowing the development and progression of ovarian cancer.

In order to effectively improve the capability of equipment fault prediction and realize state maintenance, this paper presents an improved hybrid model fault prediction method based on adaptive genetic neural network. It mainly uses genetic algorithm to improve the BP neural network, and iterates out the optimized initial weight gradually, introduces the strategy of adaptive adjustment of cross probability and mutation probability, and adjusts the probability of crossing or mutation according to the fitness of the individual to be crossed or changed. The example shows that the model of improved adaptive genetic neural network has better prediction effect, faster convergence speed and more generalization ability than simple BP neural network, and the performance of fault prediction is also enhanced greatly.

Neurotropic infiltrative growth and distant metastasis are the main causes of death in salivary adenoid cystic carcinoma (SACC) patients. Long noncoding RNAs (lncRNAs) are involved in many human neoplasms, however, their potential roles in SACC are unclear. In our study, we found that ADAM metallopeptidase with thrombospondin type 1 motif, 9 (ADAMTS9) antisense RNA 2 (ADAMTS9-AS2) was significantly upregulated in SACC patients with metastasis and SACC-lung metastasis (LM) cells. Moreover, ADAMTS9-AS2 expression was closely associated with the prognosis and distant metastasis in SACC patients. Next, we found that c-myc could specifically bind to the promoter of ADAMTS9-AS2 and activated its transcription. Knockdown of ADAMTS9-AS2 significantly inhibited migration and invasion of SACC cells in vitro and distant lung metastasis in vivo. Furthermore, ADAMTS9-AS2, which mainly expressed in the cytoplasm, shared microRNA (miRNA) response elements with Integrin α6 (ITGA6). Overexpression of ADAMTS9-AS2 competitively bound to miR-143-3p that inhibited ITGA6 from miRNA-mediated degradation, and thus it activated the activity of PI3K/Akt and MEK/Erk signaling and facilitated SACC metastasis. In summary, ADAMTS9-AS2 promotes migration and invasion in SACC by competing with miR-143-3p. This sheds a new insight into the regulation mechanism of ADAMTS9-AS2, and it provides a possible application for the SACC treatment.

Numerous findings have demonstrated that long noncoding RNA (lncRNA) dysregulation plays a key role in many human neoplasms, including tongue squamous cell carcinoma (TSCC), yet the potential mechanisms of lncRNAs in chemo-resistance remain elusive. Our research showed that the lncRNA KCNQ1OT1 was upregulated in chemo-insensitive TSCC tissues compared with chemo-sensitive TSCC specimens. Meanwhile, high KCNQ1OT1 expression was closely correlated with poor prognosis. Furthermore, KCNQ1OT1 promoted TSCC proliferation and conferred TSCC resistance to cisplatin-induced apoptosis in vitro and in vivo. Using online database analysis, we predicted that the lncRNA KCNQ1OT1 facilitates tumor growth and chemo-resistance by acting as a competing endogenous RNA (ceRNA) to modulate the expression of miR-211-5p. And miR-211-5p upregulation significantly impaired TSCC proliferation and resumed TSCC chemo-sensitivity, which is contrary to the function of lncRNA KCNQ1OT1. Luciferase experiments confirmed that miR-211-5p harbor binding sites for the 3′-UTRof Ezrin mRNA, and Ezrin/Fak/Src signaling was activated in cisplatin-resistant TSCC cells. Finally, miR-211-5p inhibition in sh-KCNQ1OT1-expressing TSCC cells rescued the suppressed cell proliferation and cisplatin resistance induced by KCNQ1OT1 knockdown. In summary, our study has elucidated the role of the oncogenic lncRNA KCNQ1OT1 in TSCC growth and chemo-resistance, which may serve as a new target for TSCC therapy.

Replacing precious noble-metal catalysts with non-precious metal ones is a well-recognized strategy for reducing the cost of catalytic water treatment. The implementation of this strategy is, however, challenging. To reduce the cost by using non-precious metal catalysts, the reactivity ratio between non-precious and precious metal catalysts must exceed their price ratio. Here, we report for the first time that the parity condition has been surpassed for cobalt (Co), in comparison to the most active precious metal catalyst made of palladium, in the catalytic reduction of p-nitrophenol with borohydride. This is achieved by affixing Co nanoparticles on two-dimensional layered double oxide (LDO) nano disks through thermal phase transformation of cobalt-magnesium–aluminum layered double hydroxide precursors. We show that the catalytic activity of LDO–Co is a function of Co molar fraction among metal cations. The highest reactivity is achieved at a molar fraction of 28%, giving a pseudo first order rate constant of 86(±3) min−1 at 25 °C for a catalyst dose of 1 g L−1 (as Co) and an initial p-nitrophenol concentration of 0.2 mM. Compared to other Co nano-catalysts described in the literature, the LDO–Co design has improved the reactivity of cobalt by at least 49 times. We further show that the high reactivity of LDO–Co remains after repeated reuse as well as after borohydride is replaced by formate, a moderate reductant and hydrogen donor. We propose that the high reactivity and superior longevity of LDO–Co are results of the heteroepitaxial fixation of cobalt on LDO through cobalt–oxygen bonds that are similar to those in spinel cobalt oxide.

Metal-catalyzed hydrolysis is an important reaction for releasing hydrogen stored in ammonia borane, a promising fuel form for the future hydrogen economy, under ambient conditions. A variety of catalysts made of different transition metals have been investigated to improve the efficiency of hydrogen generation; however, little attention has been given to the possible influence of the compensation effect on catalyst design. Using face-centered cubic (FCC) packed ruthenium (Ru) nanoparticles supported on layered double oxide nanodisks, we show that the compensation effect produces an isokinetic temperature at Ti = 17.5(±1.6) °C within the operational range of hydrogen generation. We further show that the turnover frequency (TOF) of the reaction can be maximized for operations performed below Ti by reducing the size of Ru-FCC nanoparticles, which increases the fraction of edge and corner atoms and lowers the activation energy. At 15 °C, TOF can reach more than 90% of the theoretical maximum (0.72 mol m–2 h–...

Blending noble metal catalysts with inexpensive transition metals can reduce material cost in catalytic water treatment by improving the catalytic reactivity. An important challenge is, however, to synthesize a series of alloy nanoparticles with varied compositions so that the screening of catalytic reactivity can be performed rapidly for a contaminant of interest. Here, we report a facile approach for the rapid synthesis of bimetallic nanoalloys using cycle-controlled microwave-assisted polyol reduction, with an option of fixing the nanoalloys directly on graphene supports in a one-pot operation. Using Pt and Ni as the model noble and promoter metals, we show that Pt/Ni nanoparticles with diameters ranging from 2.8 to 4 nm can be readily synthesized within minutes. The surface Ni percentage of the nanoparticles are varied from 0 to 100%, which serves as a model system for nanoalloy screening. Using the model contaminant p-nitrophenol, we further show that the reactivity-composition relationship has a classic volcano shape as the Sabatier principle predicts. The highest reactivity is found with a surface Ni percentage of approximately 50%.

The development of accurate, reliable and low cost devices for glucose detection is one of the most important scientific and technological hotspots. In this study, we proposed a unique one-step thermal synthesis strategy to synthesize nickel (Ni) nanoparticles modified graphene (GE) sheets by using metal-oleate complex as the precursor and sodium sulfate as a template. With the assistance of sodium sulfate particles, Ni nanoparticles with particle size of about 99.2nm were homogenously anchored on graphene nanosheets in the product. The electrochemical behavior of the nanocomposite towards enzyme-free glucose oxidation was investigated systematically by cyclic voltammetry and amperometric measurements. The results reveal that the GE/Ni nanocomposite exhibited excellent electrocatalytic response to glucose with a wide linear range of 0.01-2.5mM, a low detection limit of 0.79μM, and a high sensitivity of 388.4μA mM-1cm-2. In addition, no significant interference was observed from potential interference species. The simple, efficient and scalable synthesis and the excellent catalytic performance endow the GE/Ni nanocomposite great potential application in enzymeless glucose detection.

This study investigated the cotransport of titanium dioxide nanoparticles (nTiO2) and fullerene nanoparticles (nC60), two of the most widely utilized nanoparticles, in saturated quartz sand under a series of ionic strengths in NaCl solutions (0.1-10 mM) at both pH 5 and 7. Under all examined ionic strengths at pH 5, both breakthrough curves and retained profiles of nTiO2 in the copresence of nC60 were similar to those without nC60, indicating that nC60 nanoparticles copresent in suspensions did not significantly affect the transport and retention of nTiO2 in quartz sand at pH 5. In contrast, under all examined ionic strengths at pH 7, the breakthrough curves of nTiO2 in the copresence of nC60 in suspensions were higher and the retained profiles were lower than those without nC60, which demonstrated that the presence of nC60 in suspensions increased the rate of transport (decreased retention) of nTiO2 in quartz sand at pH 7. Competition of deposition sites on quartz sand surfaces by the copresence of nC60 was found to contribute to the increased nTiO2 transport at pH 7. Under all examined ionic strength conditions at both pH 5 and 7, the breakthrough curves of nC60 were reduced in the copresence of nTiO2, and the corresponding retained profiles were higher than those without nTiO2, indicating that the presence of nTiO2 decreased the transport of nC60 in quartz sand. Co-deposition of nC60 with nTiO2 in the form of nTiO2-nC60 clusters as well as the deposition of nC60 onto previously deposited nTiO2 were responsible for the increased nC60 deposition in the presence of nTiO2 at pH 5, whereas deposition of nC60 onto surfaces of predeposited nTiO2 was found to be responsible for the increased nC60 deposition at pH 7.

In this study, reduced graphene oxide (RGO) supported Ni nanoparticles were synthesized by a facile in-situ refluxing approach using triethylene glycol as both reductive and dispersing agent. The as-synthesized RGO/Ni nanocomposites were characterized by X-ray diffraction, Raman spectroscopy and transmission electron microscopy, which revealed that Ni nanoparticles with hexagonal close-packed structure were homogeneously dispersed on the surface of RGO sheets. The catalytic activity and electrochemical properties of the RGO/Ni nanocomposites were investigated. It is found that the RGO/Ni nanocomposites exhibit markedly enhanced catalytic activity toward the reduction of p -nitrophenol by NaBH 4 , which is comparable to noble metal catalyst. The RGO/Ni nanocomposites also exhibited excellent electrocatalytic response to glucose. The linear range, detection limit and sensitivity were estimated to be 0.01–3.0 mM ( R 2 = 0.997), 2.8 μM and 535.258 μA mM −1 cm −2 , respectively. It is expected that this facile method presented here could be extended to synthesize other RGO/metal nanocomposites with various functions.

Background and Purpose Antiplatelet therapy is widely used for the primary or secondary prevention of stroke. Drugs like clopidogrel have emerged as alternatives for traditional antiplatelet therapy, and dual therapy with clopidogrel and aspirin is of particular interest. We conducted this meta-analysis to systematically review studies about dual therapy comparing monotherapy with aspirin alone. Methods Randomized controlled trials were searched in PubMed (1966-May, 2015), EMBASE (1947-May, 2015), the Cochrane Central Register of Controlled Trials (CENTRAL) (1948-May, 2015), WHO International Clinical Trial (ICTRP) (2004-May, 2015), China Biology Medicine disc (CBM disc) (1978-May, 2015) and were included into the final analysis according to the definite inclusion criteria mentioned in the study selection section. Risk ratio (RR) was pooled with 95% confidence interval (CI) for dichotomous data. The heterogeneity was considered significant if the χ2 test was significant (P value 50.00%. Subgroup analyses were carried out on the long and short time periods, the race and region. Results We included 5 studies involving 24,084 patients. A pooled analysis showed that dual therapy with clopidogrel and aspirin had a lower stroke incidence than monotherapy in both the short term and long term (RR = 0.69, 95% CI: 0.59–0.82, P

Carbon nanotubes (CNTs) are promising nanomaterials that have the potential to revolutionize water treatment practices in the future. The direct use of unbounded CNTs, however, poses health risks to humans and ecosystems because they are difficult to separate from treated water. Here, we report the design and synthesis of carbon nanotube ponytails (CNPs) by integrating CNTs into micrometer-sized colloidal particles, which greatly improves the effectiveness of post-treatment separation using gravitational sedimentation, magnetic attraction, and membrane filtration. We further demonstrate that CNPs can effectively perform major treatment tasks including adsorption, disinfection, and catalysis. Using model pollutants such as methylene blue, Escherichia coli, and p-nitrophenol, we show that all the surfaces of individual CNTs in CNPs are accessible during water treatment. Our results suggest that the rational design of hierarchical structures represents a feasible approach to develop nanomaterials for engineering applications such as water and wastewater treatment.