We probe electro-mechanical properties of InAs nanowire (diameter ∼100 nm) resonators where the suspended nanowire (NW) is also the active channel of a field effect transistor (FET). We observe and explain the non-monotonic dispersion of the resonant frequency with DC gate voltage). The effect of electronic screening on the properties of the resonator can be seen in the amplitude. We observe the mixing of mechanical modes with V DC g . We also experimentally probe and quantitatively explain the hysteretic non-linear properties, as a function of V DC g , of the resonator using the Duffing equation.
Electromechanical effects are important in semiconductor nanostructures as most of the semiconductors are piezoelectric in nature. These nanostructures find applications in electronic and optoelectronic devices where they may face challenges for thermal management. Low dimensional semiconductor nanostructures, such as quantum dots (QD) and nanowires, are the nanostructures where such challenges must be particularly carefully addressed. In this contribution we report a study on thermoelectromechanical effects in QDs. For the first time a coupled model of thermoelectroelasticity has been applied to the analysis of quantum dots and the influence of thermoelectromechanical effects on bandstructures of low dimensional nanostructures has been quantified. Finite element solutions are obtained for different thermal loadings and their effects on the electromechanical properties and bandstructure of QDs are presented. Our model accounts for a practically important range of internal and external thermoelectromechanical loadings. Results are obtained for typical QD systems based on GaN/AlN and CdSe/CdS (as representatives of III-V and II-VI group semiconductors, respectively), with cylindrical and truncated conical geometries. The wetting layer effect on electromechanical quantities is also accounted for. The energy bandstructure calculations for various thermal loadings are performed. Electromechanical fields are observed to be more sensitive to thermal loadings in GaN/AlN QDs as compared to CdSe/CdS QDs. The results are discussed in the context of the effect of thermal loadings on the performance of QD-based nanosystems.
Prediction of wind speed in the atmospheric boundary layer is important for wind energy assessment, satellite launching and aviation, etc. There are a few techniques available for wind speed prediction, which require a minimum number of input parameters. Four different statistical techniques, viz., curve fitting, Auto Regressive Integrated Moving Average Model (ARIMA), extrapolation with periodic function and Artificial Neural Networks (ANN) are employed to predict wind speed. These methods require wind speeds of previous hours as input. It has been found that wind speed can be predicted with a reasonable degree of accuracy using two methods, viz., extrapolation using periodic curve fitting and ANN and the other two methods are not very useful.
Attaining sufficient tissue exposure at the site of action to achieve the desired pharmacodynamic effect on a target is an important determinant for any drug discovery program, and this can be particularly challenging for oligonucleotides in deep tissues of the CNS. Herein, we report the synthesis and impact of stereopure phosphoryl guanidine-containing backbone linkages (PN linkages) to oligonucleotides acting through an RNase H-mediated mechanism, using Malat1 and C9orf72 as benchmarks. We found that the incorporation of various types of PN linkages to a stereopure oligonucleotide backbone can increase potency of silencing in cultured neurons under free-uptake conditions 10-fold compared with similarly modified stereopure phosphorothioate (PS) and phosphodiester (PO)-based molecules. One of these backbone types, called PN-1, also yielded profound silencing benefits throughout the mouse brain and spinal cord at low doses, improving both the potency and durability of response, especially in difficult to reach brain tissues. Given these benefits in preclinical models, the incorporation of PN linkages into stereopure oligonucleotides with chimeric backbone modifications has the potential to render regions of the brain beyond the spinal cord more accessible to oligonucleotides and, consequently, may also expand the scope of neurological indications amenable to oligonucleotide therapeutics.
Aims:There has been much speculation and discussion about the infective complications of percutaneous nephrolithotomy (PCNL). While fever is common after PCNL, the incidence of it progressing to urosepsis is fortunately less. Which patient undergoing PCNL is at risk of developing urosepsis and in whom aggressive treatment of fever postoperatively may prevent the progression to severe sepsis becomes a very important question. This study aims to answer these vital questions.Settings and Design:This is a single institutional, retrospective study over a period of 3 years.Materials and Methods:Retrospective analysis of medical records of the patients undergoing PCNL from August 2012 to July 2015 was done. A total of 580 patients were included in the study, and the study variables recorded were analyzed statistically.Statistical Analysis Used:Statistical analysis was performed by Chi-square test.Results:Three factors significantly correlated with postoperative severe sepsis, namely, stone size >25 mm, prolonged operative time >120 min, and significant bleeding requiring transfusion. Factors associated with fever after PCNL which did not progress to sepsis were the presence of staghorn calculi and multiple access tracts in addition to the factors listed above for sepsis.Conclusions:Fever after PCNL is not uncommon but it has a low incidence of progressing to life-threatening severe sepsis and multiorgan dysfunction syndrome. Special precautions and monitoring should be taken in patients with bigger stone (>25 mm) and patients with severe intraoperative hemorrhage requiring blood transfusion. It is better to stage the procedure rather than prolong the operative time (120 min). Identifying these factors and minimizing them may decrease the incidence of this life-threatening complication.
In this contribution the electromechanical effects in II-VI group semiconductor finite length embedded nanowires (NWs) are analysed with fully coupled models of electroelasticity. First, strain distributions are obtained using analytical expressions derived from the Eshelby formulation with an assumption of isotropy. These results are then compared with general three-dimensional model based calculations, accounting for anisotropy and piezoelectricity. Next, as representatives of group II-VI NW systems we take zincblende CdTe/ZnTe and wurtzite CdSe/CdS crystal structured materials. The detailed analysis of strain relaxation along with electromechanical distributions are presented for common cross-sectional shapes of NWs such as triangular, square and crescent. Comparative results for both models, analytic and numerical, are presented and their applicability is discussed. The effects of the finite length of the NWs on electromechanical distributions are also discussed.
Low-dose aspirin can be safely continued perioperatively during RARP, without increasing the bleeding-related complications and overall 90-day complication rates.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.