Visualizing Atomic-Scale Negative Differential Resistance in Bilayer Graphene

We investigate the atomic-scale tunneling characteristics of bilayer graphene on silicon carbide using the scanning tunneling microscopy. The high-resolution tunneling spectroscopy reveals an unexpected negative differential resistance (NDR) at the Dirac energy, which spatially varies within the single unit cell of bilayer graphene. The origin of NDR is explained by two near-gap van Hove singularities emerging in the electronic spectrum of bilayer graphene under a transverse electric field, which are strongly localized on two sublattices in different layers. Furthermore, defects near the tunneling contact are found to strongly impact on NDR through the electron interference. Our result provides an atomic-level understanding of quantum tunneling in bilayer graphene, and constitutes a useful step towards graphene-based tunneling devices. DOI: 10.1103/PhysRevLett.110.036804X11109sciescopu

A Statistical Model for the Geotechnical Parameters of Cement-Stabilised Hightown's Soft Soil: A Case Study of Liverpool, UK

This study investigates the effect of two important parameters (length of curing period and percentage of the added binder) on the strength of soil treated with OPC. An intermediate plasticity silty clayey soil with medium organic content was used in this study. This soft soil was treated with different percentages of a commercially available cement type 32.5-N. laboratory experiments were carried out on the soil treated with 0, 1.5, 3, 6, 9, and 12% OPC by the dry weight to determine the effect of OPC on the compaction parameters, consistency limits, and the compressive strength .Unconfined compressive strength test (UCS) was carried out on cement treated specimens after exposing them to different curing periods (1, 3, 7, 14, 28, and 90 days). The results of UCS test were used to develop a non-linear multiple regression model to find the relationship between the predicted and the measured maximum compressive strength of treated soil (qu). The results indicated that there were a significant improvement in the index of plasticity (IP) with treating by OPC; IP was decreased from 21 to 14.1 by using 12% of OPC; this percentage was enough to increase the unconfined compressive strength of the treated soil up to 1362kPa after 90 days of curing. With respect to the statistical model of the predicted qu, the results showed that the regression coefficients (R2) was equal to 0.8534 which indicates a good reproducibility for the constructed model

Management of first-trimester miscarriage: a systematic review and network meta-analysis

Background First-trimester miscarriage affects up to a quarter of women worldwide. With many competing treatment options available, there is a need for a comprehensive evidence synthesis. Objectives and rationale We conducted a systematic review and network meta-analysis to assess the effectiveness and safety of treatment options for first-trimester miscarriage: expectant management (EXP), sharp dilation and curettage (D+C), electric vacuum aspiration (EVAC), manual vacuum aspiration (MVA), misoprostol alone (MISO), mifepristone+misoprostol (MIFE+MISO) and misoprostol plus electric vacuum aspiration (MISO+EVAC). Search methods We searched MEDLINE, Embase, CINAHL, AMED and Cochrane Library from inception till June 2018. We included randomized trials of women with first-trimester miscarriage (<14 weeks gestation) and conducted a network meta-analysis generating both direct and mixed evidence on the effectiveness and side effects of available treatment options. The primary outcome was complete evacuation of products of conception. We assessed the risk of bias and the global network inconsistency. We compared the surface under the cumulative ranking curve (SUCRA) for each treatment. Outcomes A total of 46 trials (9250 women) were included. The quality of included studies was overall moderate with some studies demonstrating a high risk of bias. We detected unexplained inconsistency in evidence loops involving MIFE+MISO and adjusted for it. EXP had lower effectiveness compared to other treatment options. The effectiveness of medical treatments was similar compared to surgery. Mixed evidence of low confidence suggests increased effectiveness for MIFE+MISO compared to MISO alone (RR 1.49, 95% CI: 1.09–2.03). Side effects were similar among all options. Fewer women needed analgesia following EVAC compared to MISO (RR for MISO 0.43, 95% CI: 0.27–0.68) and in the EXP group compared to EVAC (RR 2.07, 95% CI: 1.25–3.41). MVA had higher ranking (low likelihood) for post-treatment infection and serious complications (SUCRA 87.6 and 79.2%, respectively) with the highest likelihood for post-treatment satisfaction (SUCRA 98%). Wider implications Medical treatments for first-trimester miscarriage have similar effectiveness and side effects compared to surgery. The addition of MIFE could increase the effectiveness of MISO and reduce side effects, although evidence is limited due to inconsistency. EXP has lower effectiveness compared to other treatment options

Morin, A Flavonoid, On Lipid Peroxidation And Antioxidant Status In Experimental Myocardial Ischemic Rats

Background: Myocardial infarction affects a large population in the world. Lipid peroxide metabolism plays an important role in the pathology of myocardial infarction. Objective: The present study was designed to investigate the antioxidant potential of morin, a flavonoid in isoproterenol (ISO)-induced myocardial infarction (MI), in rats.Materials and Methods: Male albino Wistar rats were pre-treated with morin (40 mg/kg), daily for a period of 30 days. After the treatment period, ISO (85 mg/kg), was subcutaneously injected in rats at an interval of 24 h for 2days.Re s u l t s : ISO-administered rats showed elevated levels of thiobarbituric acid reactive substances (TBARS), and lipid hydro-peroxide (LOOH), in plasma and heart. Pretreatment with morin, the above changes were significantly reduced to near normal level. ISOadministered rats showed decrease in the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) in heart. In addition, decrease the levels non enzymatic antioxidants such as reduced glutathione (GSH), vitamin C and vitamin E in plasma and heart while ceruloplasmin in plasma.Conclusion: Pretreatment with morin, reversed these above biochemical changes towards normalcy. These findings revealed that, the morin possess antioxidant activity in experimentally induced cardiac toxicity.Key words: Morin, Isoproterenol, Myocardial infarction, Lipid peroxidation, Antioxidant

Removal of Nitrogen Compounds from Industrial Wastewater Using Sequencing Batch Reactor: The Effects of React Time

This study was performed to optimise the react time (RT) and study its effects on the removal rates of nitrogen compounds in a sequencing batch reactor (SBR) treating synthetic industrial wastewater. The results showed that increasing the RT from 4 h to 10, 16 and 22 h significantly improved the nitrogen compounds’ removal efficiency, it was increased from 69.5% to 95%, 75.7 to 97% and from 54.2 to 80.1% for NH3-N, NO3-N and NO2-N respectively. The results obtained from this study showed that the RT of 22 h was the optimum for nitrogen compounds removal efficiency

Influence of Cardiospermum halicacabum leaf extract on membrane-bound ATPases in streptozotocin-induced diabetic rats

Background: Cardiospermum halicacabum L. proved to have anti-inflammatory, antihyperglycemic, antioxidant, antiglycation, analgesic and antipyretic activities. It also has been used in Ayurveda and folk medicine for the treatment of rheumatism, fever and earache.Objective: The present study was aimed to evaluate the effect of Cardiospermum halicacabum leaf extract (CHE) on membrane-bound ATPases in streptozotocin (STZ)-induced diabetic rats.Methods: Diabetes was induced in male albino Wistar rats by intraperitonial administration of STZ (40 mg/kg BW). CHE (200 mg/kg BW) or glibenclamide (600 μg/kg BW) was administered orally once daily for 45 days to normal and STZ-induced diabetic rats.Results: The activities of membrane-bound ATPases such as total ATPase, Na+/K+-ATPase, Mg2+-ATPase and Ca2+-ATPase were significantly decreased in erythrocytes and tissues of STZ-induced diabetic rats. Oral administration of CHE to diabetic rats significantly increased the activities of these enzymes towards near normalcy.Conclusions: Thus, the present study indicates that the beneficial role of membrane-bound ATPases in STZ-induced diabetic rats. The antihyperglycemic, antioxidant and antihyperlipidemic properties of CHE could be helpful to maintain the activities of membrane-bound ATPases in STZ-induced diabetic rats showing the membrane stabilizing property of extract.Keywords: Streptozotocin, blood glucose, diabetes, membrane-bound ATPases, Cardiospermum halicacabu

Electronic Instability in a Zero-Gap Semiconductor: The Charge-DensityWave in (TaSe4)(2)I

We report a comprehensive study of the paradigmatic quasi-1D compound (TaSe4)(2)I performed by means of angle-resolved photoemission spectroscopy (ARPES) and first-principles electronic structure calculations. We find it to be a zero-gap semiconductor in the nondistorted structure, with non-negligible interchain coupling. Theory and experiment support a Peierls-like scenario for the charge-density wave formation below T-CDW = 263 K, where the incommensurability is a direct consequence of the finite interchain coupling. The formation of small polarons, strongly suggested by the ARPES data, explains the puzzling semiconductor-to-semiconductor transition observed in transport at T-CDW.open114sciescopu

A novel methodology to predict monthly municipal water demand based on weather variables scenario

This study provides a novel methodology to predict monthly water demand based on several weather variables scenarios by using combined techniques including discrete wavelet transform, principal component analysis, and particle swarm optimisation. To our knowledge, the adopted approach is the first technique to be proposed and applied in the water demand prediction. Compared to traditional methods, the developed methodology is superior in terms of predictive accuracy and runtime. Water consumption coupled with weather variables of the Melbourne City, from 2006 to 2015, were obtained from the South East Water retail company. The results showed that using data pre-processing techniques can significantly improve the quality of data and to select the best model input scenario. Additionally, it was noticed that the particle swarm optimisation algorithm accurately predicts the constants of the suggested model. Furthermore, the results confirmed that the proposed methodology accurately estimated the monthly data of municipal water demand based on a range of statistical criteria