Strongly reduced bias dependence in spin-tunnel junctions obtained by ultraviolet light assisted oxidation

For future implementation of ferromagnetic tunnel junctions, we need a better understanding of the influence of the insulating barrier preparation method on the junction resistance, tunnel magnetoresistance (TMR), and its voltage bias dependence. In this letter, we focus on the bias dependence of junctions (Co-Al2O3-Ni80Fe20) prepared by ultraviolet light assisted in situ oxidation in an O-2 ambient. For an initial Al thickness of 1.3 nm, the resistance times area product of the junctions is 60 k Omega mu m(2), while showing up to 20% TMR at 5 mV bias. The decrease of TMR with bias voltage up to 1 V is remarkably small leading to V-1/2, for which half of the low-bias TMR remains, well over 0.6 V. (C) 2000 American Institute of Physics. [S0003-6951(00)02908-9]

Codesigning consumer engagement strategies with ethnic minority consumers in Australian cancer services: The CanEngage Project protocol

Introduction Consumer engagement is central to high-quality cancer service delivery and is a recognised strategy to minimise healthcare-associated harm. Strategies developed to enhance consumer engagement specifically in relation to preventing healthcare harm include questioning health professionals, raising concerns about possible mistakes or risks in care and encouraging patients and caregivers to report suspected errors. Patients from ethnic minority backgrounds are particularly vulnerable to unsafe care, but current engagement strategies have not been developed specifically for (and with) this population. Using an adapted approach to experience-based codesign (EBCD) to support the target population, the aim of the project is to codesign consumer engagement interventions to increase consumer engagement and safety in New South Wales and Victorian cancer inpatient, outpatient and day procedure services. Methods and analysis A mixed-method project will be undertaken at six study sites. Our EBCD approach includes a preparatory phase in which we will provide training and support to the codesign participants, in addition to recruiting and training consumer cofacilitators for the codesign workshops. The project will follow the EBCD process of gathering and synthesising observational data from each cancer service, with interview data from consumers and staff. With the resulting in-depth understanding of the safety threats commonly experienced by ethnic minority consumers in each site, we will work through feedback events and codesign groups with consumers and staff to determine how they can be more involved with their care to minimise the potential for patient harm. Consumer engagement interventions will be coproduced in each of the six participating services that are tailored to the ethnic minority populations served. Ethics and dissemination Ethics approval has been obtained from the Western Sydney Local Health District Human Research Ethics Committee. The project will provide strategies for ethnic minority consumers to engage with cancer services to minimise healthcare-associated harm that may be applied to diverse healthcare settings

Effect of microstructural evolution on magnetic properties of Ni thin films

Copyright © Indian Academy of Sciences.The magnetic properties of Ni thin films, in the range 20–500 nm, at the crystalline-nanocrystalline interface are reported. The effect of thickness, substrate and substrate temperature has been studied. For the films deposited at ambient temperatures on borosilicate glass substrates, the crystallite size, coercive field and magnetization energy density first increase and achieve a maximum at a critical value of thickness and decrease thereafter. At a thickness of 50 nm, the films deposited at ambient temperature onto borosilicate glass, MgO and silicon do not exhibit long-range order but are magnetic as is evident from the non-zero coercive field and magnetization energy. Phase contrast microscopy revealed that the grain sizes increase from a value of 30–50 nm at ambient temperature to 120–150 nm at 503 K and remain approximately constant in this range up to 593 K. The existence of grain boundary walls of width 30–50 nm is demonstrated using phase contrast images. The grain boundary area also stagnates at higher substrate temperature. There is pronounced shape anisotropy as evidenced by the increased aspect ratio of the grains as a function of substrate temperature. Nickel thin films of 50 nm show the absence of long-range crystalline order at ambient temperature growth conditions and a preferred [111] orientation at higher substrate temperatures. Thin films are found to be thermally relaxed at elevated deposition temperature and having large compressive strain at ambient temperature. This transition from nanocrystalline to crystalline order causes a peak in the coercive field in the region of transition as a function of thickness and substrate temperature. The saturation magnetization on the other hand increases with increase in substrate temperature.University Grants Commission for Centre of Advanced Studies in Physic

Fitness Landscape Transformation through a Single Amino Acid Change in the Rho Terminator

Regulatory networks allow organisms to match adaptive behavior to the complex and dynamic contingencies of their native habitats. Upon a sudden transition to a novel environment, the mismatch between the native behavior and the new niche provides selective pressure for adaptive evolution through mutations in elements that control gene expression. In the case of core components of cellular regulation and metabolism, with broad control over diverse biological processes, such mutations may have substantial pleiotropic consequences. Through extensive phenotypic analyses, we have characterized the systems-level consequences of one such mutation (rho*) in the global transcriptional terminator Rho of Escherichia coli. We find that a single amino acid change in Rho results in a massive change in the fitness landscape of the cell, with widely discrepant fitness consequences of identical single locus perturbations in rho* versus rhoWT backgrounds. Our observations reveal the extent to which a single regulatory mutation can transform the entire fitness landscape of the cell, causing a massive change in the interpretation of individual mutations and altering the evolutionary trajectories which may be accessible to a bacterial population

The femoral insertions of the anteromedial and posterolateral bundles of the anterior cruciate ligament: a radiographic evaluation

The aim of this radiographic study was to visualize the femoral insertion sites of the anteromedial (AM) and posterolateral (PL) bundle of the anterior cruciate ligament (ACL) on lateral radiographs in different angles of knee flexion to gain better understanding for arthroscopic femoral tunnel placement in ACL double bundle reconstruction. Four fresh cadaveric knees with an intact ACL were dissected to isolate the AM and PL bundle of the ACL. We obtained lateral radiographs of each knee over the range of 0°–90° flexion in 30° increments after painting the bundles with a radiopaque tantalum powder. The center of the radiographically marked femoral insertion was defined for each bundle on the lateral roentgenogram. We analyzed the relationship of knee flexion and the projection of the relative position of the femoral insertion sites of both bundles of the ACL on the lateral roentgenogram. The centre of the PL bundle visualized more anterior and distal than the centre of the AM bundle with the knee held in 90° flexion. The centers of the AM and PL bundle were horizontally aligned when the knee was flexed over 90°. The resulting images allow a radiographic description of the femoral insertion sites of both bundles in different angles of knee flexion. It is essential to be aware of the degree of knee flexion when drilling the femoral tunnels

Simvastatin ameliorates established pulmonary hypertension through a heme oxygenase-1 dependent pathway in rats

<p>Abstract</p> <p>Background</p> <p>Simvastatin has been shown to ameliorate pulmonary hypertension by several mechanisms in experimental animal models. In this study, we hypothesized that the major benefits of simvastatin in pulmonary hypertension occur via the heme oxygenase-1 pathway.</p> <p>Methods</p> <p>Simvastatin (10 mg/kgw/day) was tested in two rat models of pulmonary hypertension (PH): monocrotaline administration and chronic hypoxia. The hemodynamic changes, right heart hypertrophy, HO-1 protein expression, and heme oxygenase (HO) activity in lungs were measured in both models with and without simvastatin treatment. Tin-protoporphyrin (SnPP, 20 μmol/kg w/day), a potent inhibitor of HO activity, was used to confirm the role of HO-1.</p> <p>Results</p> <p>Simvastatin significantly ameliorated pulmonary arterial hypertension from 38.0 ± 2.2 mm Hg to 22.1 ± 1.9 mm Hg in monocrotaline-induced PH (MCT-PH) and from 33.3 ± 0.8 mm Hg to 17.5 ± 2.9 mm Hg in chronic hypoxia-induced PH (CH-PH) rats. The severity of right ventricular hypertrophy was significantly reduced by simvastatin in MCT-PH and CH-PH rats. Co-administration with SnPP abolished the benefits of simvastatin. Simvastatin significantly increased HO-1 protein expression and HO activity in the lungs of rats with PH; however co-administration of SnPP reduced HO-1 activity only. These observations indicate that the simvastatin-induced amelioration of pulmonary hypertension was directly related to the activity of HO-1, rather than its expression.</p> <p>Conclusion</p> <p>This study demonstrated that simvastatin treatment ameliorates established pulmonary hypertension primarily through an HO-1-dependent pathway.</p

Pleiotropic effects of statins in distal human pulmonary artery smooth muscle cells

<p>Abstract</p> <p>Background</p> <p>Recent clinical data suggest statins have transient but significant effects in patients with pulmonary arterial hypertension. In this study we explored the molecular effects of statins on distal human pulmonary artery smooth muscle cells (PASMCs) and their relevance to proliferation and apoptosis in pulmonary arterial hypertension.</p> <p>Methods</p> <p>Primary distal human PASMCs from patients and controls were treated with lipophilic (simvastatin, atorvastatin, mevastatin and fluvastatin), lipophobic (pravastatin) and nitric-oxide releasing statins and studied in terms of their DNA synthesis, proliferation, apoptosis, matrix metalloproteinase-9 and endothelin-1 release.</p> <p>Results</p> <p>Treatment of human PASMCs with selected statins inhibited DNA synthesis, proliferation and matrix metalloproteinase-9 production in a concentration-dependent manner. Statins differed in their effectiveness, the rank order of anti-mitogenic potency being simvastatin > atorvastatin > > pravastatin. Nevertheless, a novel nitric oxide-releasing derivative of pravastatin (NCX 6550) was effective. Lipophilic statins, such as simvastatin, also enhanced the anti-proliferative effects of iloprost and sildenafil, promoted apoptosis and inhibited the release of the mitogen and survival factor endothelin-1. These effects were reversed by mevalonate and the isoprenoid intermediate geranylgeranylpyrophosphate and were mimicked by inhibitors of the Rho and Rho-kinase.</p> <p>Conclusions</p> <p>Lipophilic statins exert direct effects on distal human PASMCs and are likely to involve inhibition of Rho GTPase signalling. These findings compliment some of the recently documented effects in patients with pulmonary arterial hypertension.</p

Can teaching agenda-setting skills to physicians improve clinical interaction quality? A controlled intervention

<p>Abstract</p> <p>Background</p> <p>Physicians and medical educators have repeatedly acknowledged the inadequacy of communication skills training in the medical school curriculum and opportunities to improve these skills in practice. This study of a controlled intervention evaluates the effect of teaching practicing physicians the skill of "agenda-setting" on patients' experiences with care. The agenda-setting intervention aimed to engage clinicians in the practice of initiating patient encounters by eliciting the full set of concerns from the patient's perspective and using that information to prioritize and negotiate which clinical issues should most appropriately be dealt with and which (if any) should be deferred to a subsequent visit.</p> <p>Methods</p> <p>Ten physicians from a large physician organization in California with baseline patient survey scores below the statewide 25th percentile participated in the agenda-setting intervention. Eleven physicians matched on baseline scores, geography, specialty, and practice size were selected as controls. Changes in survey summary scores from pre- and post-intervention surveys were compared between the two groups. Multilevel regression models that accounted for the clustering of patients within physicians and controlled for respondent characteristics were used to examine the effect of the intervention on survey scale scores.</p> <p>Results</p> <p>There was statistically significant improvement in intervention physicians' ability to "explain things in a way that was easy to understand" (p = 0.02) and marginally significant improvement in the overall quality of physician-patient interactions (p = 0.08) compared to control group physicians. Changes in patients' experiences with organizational access, care coordination, and office staff interactions did not differ by experimental group.</p> <p>Conclusion</p> <p>A simple and modest behavioral training for practicing physicians has potential to positively affect physician-patient relationship interaction quality. It will be important to evaluate the effect of more extensive trainings, including those that work with physicians on a broader set of communication techniques.</p

Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV

A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7 TeV is presented. The data were collected at the LHC, with the CMS detector, and correspond to an integrated luminosity of 4.6 inverse femtobarns. No significant excess is observed above the background expectation, and upper limits are set on the Higgs boson production cross section. The presence of the standard model Higgs boson with a mass in the 270-440 GeV range is excluded at 95% confidence level.Comment: Submitted to JHE

Search for New Physics with Jets and Missing Transverse Momentum in pp collisions at sqrt(s) = 7 TeV

A search for new physics is presented based on an event signature of at least three jets accompanied by large missing transverse momentum, using a data sample corresponding to an integrated luminosity of 36 inverse picobarns collected in proton--proton collisions at sqrt(s)=7 TeV with the CMS detector at the LHC. No excess of events is observed above the expected standard model backgrounds, which are all estimated from the data. Exclusion limits are presented for the constrained minimal supersymmetric extension of the standard model. Cross section limits are also presented using simplified models with new particles decaying to an undetected particle and one or two jets