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Renewable energy production via solar energy is a promising solution to advent the globally mounting energy needs. Therefore, our work has been planned to develop, high efficient optoelectronic devices, which are cost effective and easily fabricated. Successfully, we developed Al doped ZnO nanorods (NRs) by two step process. Initially by using sol-gel technique we grow the seed layers and further we succeed ZnO nanorods by a simple hydrothermal process without using any toxic solvents. The obtained nanorods show remarkable electrical and optical properties characterized by I-V characteristics, UV- vis, Photoluminescence (PL) spectroscopy techniques. In addition, we have also investigated the surface morphological properties from FESEM which indicates that NRs are hexagonal in shape and the diameter of the rod varies from 232 nm to 297 nm as the Al concentration changes from 1% to 10% in ZnO. Band gap of Al doped ZnO NR decreases on increasing the concentration of doping from 3.23 to 2.73 eV. The PL spectrum shows emission peaks in the UV and visible region. From this we conclude that, these materials are good candidate for the optoelectronic applications. Thus, our approach will probably fetch and derive a noble route for the fabrication of new materials.

Undoped and Sn doped Zinc oxide nanorods were prepared by two step process: initially growth of seed layers by sol-gel spin coating technique and then zinc oxide nanorods by hydrothermal process using the precursors zinc nitrate hexahydrate, hexamine and tin chloride. The effects on the electrical, optical, mechanical and structural properties for various Sn concentrations were studied. The crystalline phase determination from X-ray diffraction (XRD) confirms that Sn doped ZnO nanorods have hexagonal wurtzite structure. The variations of stress and strain with different doping concentration of Sn in ZnO nanorods were studied. The doping effect on electrical properties and optical bandgap is estimated by current voltage characteristics and absorbance spectra respectively. The surface morphology was studied with field emission scanning electron microscope (FESEM), which shows that the formation of hexagonal nanorods arrays with increasing Sn concentration. The calculated value of Young's modulus of elasticity (Y) for all the samples remains same. These results can be used in optoelectronic devices.

Interaction of biogenic impurities with the Ni (1 1 1) catalyst surface was studied to understand their important role in inhibiting catalysis. Non-bonding interactions of amino acids (Alanine (Ala), Cysteine (Cys), Methionine (Met), Tryptophan (Trp), Histidine (His), Lysine (Lys), Glutamic acid (Glu) and Threonine (Thr)) in aqueous environment were examined using classical molecular dynamics (MD) simulations. The potential of mean force (PMF) profiles of amino acids revealed qualitative differences, resulting into altered orientation and the choice of preferential interacting site with the metal surface. The side chains of all the amino acids were observed to align parallel to the metal surface. Amino acids containing sulfur (Met and Cys) and heterocyclic nitrogen (Trp, His) were observed to interact favorably with the Ni surface. Most of the preferential interacting sites were observed to be in direct contact with the surface except Lys which interacted with the backbone nitrogen oriented away from the surface. The strength of non-bonded interactions varied from −13 to −71 kJ/mol with Ala as the weakest and Trp as the strongest interacting amino acids. The interaction energies scaled linearly with the solvent accessible surface area of the amino acids. Density functional theory (DFT) calculations were utilized to understand the bonding interactions of sulfur (S) containing amino acids (Met and Cys) and the irreversible catalyst deactivation caused by them. DFT calculations showed strong binding for both Cys (−123 kJ/mol) and Met (−115 kJ/mol), undergoing dissociation to form atomic S on the Ni (1 1 1) surface with an intrinsic activation barrier of 32 kJ/mol and 133 kJ/mol, respectively, for the C S bond cleavage. However, the mechanistic routes for dissociation followed by the two amino acids were a bit different. While in Cys, the C-H activation was followed by C S cleavage, in Met, C S bond was activated first to form S-CH 3 species on the catalyst surface. In contrast to Met at higher coverage, Cys was observed to decompose to elemental S on the surface. The mechanistic insights thus obtained lead to an explorative theoretical framework for the design of a bimetallic catalyst, which may be used in an integrated bio and chemo-catalytic process with reduced chances of deactivation. The Ni-Au alloy surface showed lower binding energies for both Met (−88 kJ/mol) and S (−132 kJ/mol), as compared to pure Ni surface, indicating promising prospects for the activity of such an alloy catalyst.

We compare the extent to which the properties of simple liquids are pertinent to short to moderate chain n-alkanes ranging from ethane (C2) to dodecane (C12). Explicit geometric features such as bonds, angles and dihedral potentials in currently available models of n-alkanes make these systems more realistic, and distinct from the generalized Lennard-Jones chain fluids. Our study confirms that the presence of these flexible geometric constraints completely suppresses the energy-virial correlation in these systems. However, they are found to have a strong energy-virial correlation in high density region of their phase diagram when the contribution from these geometric constraints are excluded. For fluids having simple liquid like behavior, semi-quantitative relationships between structure, dynamics, and thermodynamics are well established. Range of state points is explored to test the applicability of such relationships for n-alkanes. Considering the collection of monomer beads as the reference state, thermodynamic and structural entropic measures are systematically compared with and without intramolecular contributions. We show that the pair entropy computed with explicit intramolecular geometric constraints correlates well with thermodynamic excess entropy. Both the thermodynamic and pair entropy have strong isochore dependence with reduced diffusivity. Intermolecular pair entropy correlates well with reduced diffusivity. The role of multiparticle correlations is highlighted for predicting thermodynamic and transport properties in these chain systems. Triplet correlations in addition to pair correlations are used as an attempt to improve the structural contribution to excess entropy. We show that if the three particle contribution is included in the computation of structural entropy, the resulting value overestimates the excess entropy.

Simulations utilizing molecular dynamics (MD) were applied to study the anisotropic diffusion in the a – b plane of double perovskite structure, GdBaCo 2 O 5.5 (GBCO 5.5 ). Diffusion coefficient of GBCO 5.5 was calculated to be 5 × 10 −8 cm 2 s −1 at 873 K. The calculated diffusion coefficient was observed to increase on increasing temperature with an activation energy of 50.8 kJ/mol. Similar MD simulations were employed to study the effect of the level of Fe doping at the B-site of the co-doped GdBa 0.5 Sr 0.5 Co 2−x Fe x O 5+ δ . In the co-doped structure, increasing diffusion was observed on increasing the Fe doping to x = 1 (D = 7.5 × 10 −8 cm 2 s −1 at 923 K). This was contrary to the Pr or Nd based co-doped materials, LnBa 1−y Sr y Co 2−x Fe x O 5+δ (Ln = Pr, Nd), where maximum diffusion was calculated for Fe doping level at x = 0.5 (D = 5.16 × 10 −8 cm 2 s −1 for Ln = Pr and D = 1.18 × 10 −7 cm 2 s −1 for Ln = Nd at 873 K). The trend in diffusivity correlates well with the trends in the measured peak power density of a solid oxide fuel cell fabricated with these electrode materials.

BackgroundThiazide and thiazide-like diuretic agents are being increasingly used at lower doses. Hydrochlorothiazide (HCTZ) in the 12.5-mg dose remains the most commonly prescribed antihypertensive agent in the United States.ObjectivesThis study compared chlorthalidone, 6.25 mg daily, with HCTZ, 12.5 mg daily, by 24-h ambulatory blood pressure (ABP) monitoring and evaluated efficacy. Because HCTZ has been perceived as a short-acting drug, a third comparison with an extended-release formulation (HCTZ-controlled release [CR]) was added.MethodsThis 12-week comparative, double-blind, outpatient study randomized 54 patients with stage 1 hypertension to receive either chlorthalidone, 6.25 mg, (n = 16); HCTZ 12.5 mg (n = 18); or HCTZ-CR 12.5 mg (n = 20). ABP monitoring was performed at baseline and after 4 and 12 weeks of therapy.ResultsAll 3 treatments significantly (p < 0.01) lowered office BP at weeks 4 and 12 from baseline. At weeks 4 and 12, significant reductions in systolic and diastolic 24-h ambulatory and nighttime BP (p

Background: Because nearly 23,000 more neurosurgeons are needed globally to address 5 million essential neurosurgical cases that go untreated each year, there is an increasing interest in task-shifting and task-sharing (TS/S), delegating neurosurgical tasks to nonspecialists, particularly in low- and middle-income countries (LMICs). This global survey aimed to provide a cross-sectional understanding of the prevalence and structure of current neurosurgical TS/S practices in LMICs. Methods: The survey was distributed to a convenience sample of individuals providing neurosurgical care in LMICs with a Web-based survey link via electronic mailing lists of continental societies and various neurosurgical groups, conference announcements, e-mailing lists, and social media platforms. Country-level data were analyzed by descriptive statistics. Results: The survey yielded 127 responses from 47 LMICs; 20 countries (42.6%) reported ongoing TS/S. Most TS/S procedures involved emergency interventions, the top 3 being burr holes, craniotomy for hematoma evacuation, and external ventricular drain. Most (65.0%) believed that their Ministry of Health does not endorse TS/S (24.0% unsure), and only 11% believed that TS/S training was structured. There were few opportunities for TS/S providers to continue medical education (11.6%) or maintenance of certification (9.4%, or receive remuneration (4.2%). Conclusions: TS/S is ongoing in many LMICs without substantial structure or oversight, which is concerning for patient safety. These data invite future clinical outcomes studies to assess effectiveness and discussions on policy recommendations such as standardized curricula, certification protocols, specialist oversight, and referral networks to increase the level of TS/S care and to continue to increase the specialist workforce. Key words: Capacity, Global health, Global neurosurgery, LMIC, Task-sharing, Task-shifting, Workforce

The concept of intuitionistic fuzzy soft set (IFSS) arising from intuitionistic fuzzy set (IFS) is generalized by including a parameter reflecting a moderator's opinion about the validity of the information provided. The resulting generalized intuitionistic fuzzy soft set (GIFSS) finds a special role in the decision making applications. It can evaluate the given criteria along with the moderator's assessment of the furnished data. The properties of GIFSS are investigated and the associated relations called generalized intuitionistic fuzzy soft relations (GIFSR) are given. A similarity measure is given to compare two GIFSSs. As this is not applicable to fuzzy numbers, a new score function is devised to compare two intuitionistic fuzzy numbers (IFNs), the components of IFS. The effectiveness of the proposed GIFSS in decision making is demonstrated on four case studies.

Posterior dislocation or fracture-dislocation of the shoulder is a rare entity, and is often missed in the Emergency Department. The causes include a tonic-clonic seizure, electrocution, and major trauma. The clinical presentations are often misleading and thus the correct diagnosis may be delayed. Proper imaging of the shoulder in suspected cases is important in making the correct diagnosis. We report a rare case of bilateral posterior fracture-dislocation of the shoulders, which presented in the Emergency Department with clinical features suggestive of a dissecting aneurysm of the thoracic aorta. A review of the relevant literature is also presented.

The purpose of this study was to evaluate and assess the sporting and physical activities of patients who had undergone an Oxford medial unicompartmental knee arthroplasty (UKA). Seventy-six patients who underwent a UKA between 2000 and 2003 were reviewed. Demographic data such as age, sex and comorbidities were recorded. University of California Los Angeles (UCLA) activity level ratings and Oxford knee scores were determined for each patient. The sporting and physical activities of all patients' pre- and post-operatively were recorded. The mean age of patients was 64 years (range 49-81) at surgery and 66 years (range 53-82) at review. The mean follow up time was 18 months (range 4-46). Following surgery there was a significant improvement in UCLA activity level scores from 4.2 to 6.5 (Wilcoxon Matched-pairs Signed-rank Test, p

The present work deals with the dynamics of a mechanical switching system in which the state variables are continuous at the switching events, but the first derivative of the vector field changes discontinuously across the switching boundary. Earlier works have shown that hard impacting systems yield discrete maps with a term of power 1/2, and stick-slip systems yield discrete maps with a term of power 3/2. Maps of the first kind exhibit square-root singularity while those of the second kind are smooth, and therefore no border collision bifurcation occur in them. In this Letter we consider an impacting system with a wall cushioned with spring-damper support. The spring is constrained such that the force on the mass changes discontinuously at a grazing contact. We focus our attention on the change in the Jacobian matrix of a fixed point caused by grazing. We show that a typical property of border collision in such systems is that the determinant remains invariant and the trace shows a singularity at the grazing point. We also explain the observed bifurcations based on the available theory of border collision bifurcations.

Proximal fifth metatarsal fractures distal to the tuberosity are troublesome fractures to manage with a high incidence of delayed union and non-union. We present our study of 32 patients with this fracture who were followed up for a mean of 16 months. This is one of the largest reported series of such fractures. These fractures were classified as acute fractures (14 fractures), fractures with features of delayed union (15 fractures) and fractures with features of non-union (three fractures) at presentation according to the classification used by Torg in 1984. These patients were treated in a plaster cast and mobilised either non-weight bearing or with variations of weight bearing. Our findings correspond with those observed by Torg. Prevailing guidelines for the management of these fractures are ambiguous. A standardized classification is important because there is great variability in the types of fractures and appropriate treatment. The treatment of choice is suggested in view of the clinical and radiological findings at presentation. © 2005 Elsevier Ltd. All rights reserved.

We studied 29 patients with distal femoral fractures stabilised using the less invasive stabilisation system (LISS). Four patients were excluded from the final follow-up (three deaths and one case of quadriplegia). The mean age of the remaining 25 patients (9 males and 16 females) was 60.9 years and the mean follow-up 18 months (range 12-24 months). Eleven patients were tertiary referrals from other hospitals (seven cases were referred due to failure of primary fixation). Overall, there were 12 cases of high-energy trauma (7 open fractures). According to the AO classification, there were 5 Type 33A, 2 Type 33B and 12 Type 33C fractures and 4 Type 32A, 1 Type 32B, 1 Type 32C fractures. Functional assessment was performed using the modified Hospital for Special Surgery (HSS) and the Schatzker and Lambert scores. The average time to union in 22 cases was 3.5 months (range 2-5 months). All of the acute cases united without the need for bone grafting. There were three out of seven cases of non-union in the salvage group still undergoing treatment. The overall result in the acute cases was good and in the salvage cases fair. While this is a small series of patients, our preliminary data indicate favourable results using the LISS in stabilising acute distal femoral fractures. However, when the LISS is used as a revision tool the results seem to be less satisfactory. The system appears to be user-friendly and no technical difficulties were encountered.

Unicompartmental knee arthroplasty is now being used more commonly to treat single compartment disease of knee, with very encouraging results. We report on a rare case of common peroneal nerve palsy; 8 years after lateral unicompartmental knee arthroplasty. This palsy was caused by pressure on the common peroneal nerve, due to posterior migration of tibial component.