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Here, we investigate the use of few-layer metal organic chemical vapor deposition (MOCVD) grown BN as a two-dimensional buffer layer for plasma enhanced atomic layer deposition (PE-ALD) of Al2O3 on graphene for top gated field effect transistors (FETs). The reactive nature of PE-ALD enables deposition of thin (2 nm) dielectrics directly on graphene and other two-dimensional materials without the need for a seed or functionalization layer; however, this also leads to significant oxidation of the graphene layer as observed by Raman. In FETs, we find this oxidation destroys conductivity in the graphene channel. By transferring thin (1.6 nm) MOCVD BN layers on top of graphene channels prior to PE-ALD, the graphene is protected from oxidation enabling BN/Al2O3 layers as thin as 4 nm. Raman and X-ray photoelectron spectroscopy on BN films show no significant oxidation caused by PE-ALD of Al2O3. Inserting the BN layer creates an atomically abrupt interface significantly reducing interface charges between the graphene and Al2O3 as compared to use of a 2 nm Al buffer layer. This results in a much smaller Dirac voltage (- 1 V) and hysteresis (0.9 V) when compared to FETs with the Al layer (VDirac = - 6.1 V and hysteresis = 2.9 V).
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AIMS: To evaluate whether and what combinations of diabetes quality metrics were achieved in a multicentre trial in South Asia evaluating a multicomponent quality improvement intervention that included non-physician care coordinators to promote adherence and clinical decision-support software to enhance physician practices, in comparision with usual care. METHODS: Using data from the Centre for Cardiometabolic Risk Reduction in South Asia (CARRS) trial, we evaluated the proportions of trial participants achieving specific and combinations of five diabetes care targets (HbA1c <53 mmol/mol [7%], blood pressure <130/80 mmHg, LDL cholesterol <2.6 mmol/L, non-smoking status, and aspirin use). Additionally, we examined the proportions of participants achieving the following risk factor improvements from baseline: ≥11-mmol/mol (1%) reduction in HbA1c , ≥10-mmHg reduction in systolic blood pressure, and/or ≥0.26-mmol/l reduction in LDL cholesterol. RESULTS: Baseline characteristics were similar in the intervention and usual care arms. Overall, 12.3%, 29.4%, 36.5%, 19.5% and 2.2% of participants in the intervention group and 16.2%, 38.3%, 31.6%, 11.3% and 0.8% of participants in the usual care group achieved any one, two, three, four or five targets, respectively. We noted sizeable improvements in HbA1c , blood pressure and cholesterol, and found that participants in the intervention group were twice as likely to achieve improvements in all three indices at 12 months that were sustained over 28 months of the study [relative risk 2.1 (95% CI 1.5,2.8) and 1.8 (95% CI 1.5,2.3), respectively]. CONCLUSIONS: The intervention was associated with significantly higher achievement of and greater improvements in composite diabetes quality care goals. However, among these higher-risk participants, very small proportions achieved the complete group of targets, which suggests that achievement of multiple quality-of-care goals is challenging and that other methods may be needed in closing care gaps.
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Sistemas de Apoyo a Decisiones Clínicas , Diabetes Mellitus Tipo 2/terapia , Mejoramiento de la Calidad , Indicadores de Calidad de la Atención de Salud , Aspirina/uso terapéutico , Presión Sanguínea , LDL-Colesterol/metabolismo , Atención a la Salud/organización & administración , Diabetes Mellitus Tipo 2/metabolismo , Hemoglobina Glucada/metabolismo , Humanos , India , Pakistán , Inhibidores de Agregación Plaquetaria/uso terapéutico , Calidad de la Atención de Salud , Fumar/epidemiologíaRESUMEN
AIMS: To describe physicians' acceptance of decision-support electronic health record system and its impact on diabetes care goals among people with Type 2 diabetes. METHODS: We analysed data from participants in the Centre for Cardiometabolic Risk Reduction in South Asia (CARRS) trial, who received the study intervention (care coordinators and use of a decision-support electronic health record system; n=575) using generalized estimating equations to estimate the association between acceptance/rejection of decision-support system prompts and outcomes (mean changes in HbA1c , blood pressure and LDL cholesterol) considering repeated measures across all time points available. We conducted in-depth interviews with physicians to understand the benefits, challenges and value of the decision-support electronic health record system and analysed physicians' interviews using Rogers' diffusion of innovation theory. RESULTS: At end-of-trial, participants with diabetes for whom glycaemic, systolic blood pressure, diastolic blood pressure and LDL cholesterol decision-support electronic health record prompts were accepted vs rejected, experienced no reduction in HbA1c [mean difference: -0.05 mmol/mol (95% CI -0.22, 0.13); P=0.599], but statistically significant improvements were observed for systolic blood pressure [mean difference: -11.6 mmHg (95% CI -13.9, -9.3); P ≤ 0.001], diastolic blood pressure [mean difference: -5.2 mmHg (95% CI -6.5, -3.8); P ≤ 0.001] and LDL cholesterol [mean difference: -0.7 mmol/l (95% CI -0.6, -0.8); P ≤0.001], respectively. The relative advantages and compatibility of the decision-support electronic health record system with existing clinic set-ups influenced physicians' acceptance of it. Software complexities and data entry challenges could be overcome by task-sharing. CONCLUSION: Wider adherence to decision-support electronic health record prompts could potentially improve diabetes goal achievement, particularly when accompanied by assistance from a non-physician health worker.
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Ensayos Clínicos como Asunto , Sistemas de Apoyo a Decisiones Clínicas , Registros Electrónicos de Salud , Adhesión a Directriz/estadística & datos numéricos , Planificación de Atención al Paciente , Médicos , Adulto , Asia/epidemiología , Actitud del Personal de Salud , Ensayos Clínicos como Asunto/métodos , Ensayos Clínicos como Asunto/organización & administración , Toma de Decisiones , Sistemas de Apoyo a Decisiones Clínicas/organización & administración , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/terapia , Angiopatías Diabéticas/prevención & control , Registros Electrónicos de Salud/organización & administración , Femenino , Humanos , Masculino , Persona de Mediana Edad , Planificación de Atención al Paciente/organización & administración , Médicos/psicología , Médicos/estadística & datos numéricos , Atención Primaria de Salud/métodos , Atención Primaria de Salud/organización & administración , Atención Primaria de Salud/estadística & datos numéricos , Conducta de Reducción del RiesgoRESUMEN
Electrical resistivity measurement of freshly prepared uncured and cured soil-cement materials is done and the correlations between the factors controlling the performance of soil-cement and electrical resistivity are discussed in this paper. Conventional quality control of soil-cement quite often involves wastage of a lot of material, if it does not meet the strength criteria. In this study, it is observed that, in soil-cement, resistivity follows a similar trend as unconfined compressive strength, with increase in cement content and time of curing. Quantitative relations developed for predicting 7-day strength of soil-cement mix, using resistivity of the soil-cement samples at freshly prepared state, after 1-hour curing help to decide whether the soil-cement mix meets the desired strength and performance criteria. This offers the option of the soil-cement mix to be upgraded (possibly with additional cement) in its fresh state itself, if it does not fulfil the performance criteria, rather than wasting the material after hardening.
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BACKGROUND AND PURPOSE: Neurointerventional surgery may expose patients and physician operators to substantial amounts of ionizing radiation. Although strategies for reducing patient exposure have been explored in the medical literature, there has been relatively little published in regards to decreasing operator exposure. The purpose of this study was to evaluate the efficacy of shielding systems in reducing physician exposure in a modern neurointerventional practice. MATERIALS AND METHODS: Informed consent was obtained from operators for this Health Insurance Portability and Accountability Act-compliant, institutional review board-approved study. Operator radiation exposure was prospectively measured during 60 consecutive neurointerventional procedures from October to November 2013 using a 3-part lead shielding system. Exposure was then evaluated without lead shielding in a second 60-procedure block from April to May 2014. A radiation protection drape was randomly selected for use in half of the cases in each block. Two-way analysis of covariance was performed to test the effect of shielding systems on operator exposure while controlling for other covariates, including procedure dose-area product. RESULTS: Mean operator procedure dose was 20.6 µSv for the entire cohort and 17.7 µSv when using some type of shielding. Operator exposure significantly correlated with procedure dose-area product, but not with other covariates. After we adjusted for procedure dose-area product, the use of lead shielding or a radiation protection drape significantly reduced operator exposure by 45% (F = 12.54, P < .0001) and 29% (F = 7.02, P = .009), respectively. The difference in protection afforded by these systems was not statistically significant (P = .46), and their adjunctive use did not provide additional protection. CONCLUSIONS: Extensive lead shielding should be used as much as possible in neurointerventional surgery to reduce operator radiation exposure to acceptable levels. A radiation protection drape is a reasonable alternative when standard lead shielding is unavailable or impractical to use without neglecting strategies to minimize the dose.
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Exposición Profesional/prevención & control , Médicos , Exposición a la Radiación/prevención & control , Protección Radiológica/métodos , Radiografía Intervencional/efectos adversos , Femenino , Humanos , Masculino , Estudios Prospectivos , Dosis de Radiación , Radiografía Intervencional/métodosRESUMEN
Reversible cerebral vasoconstriction syndrome is a clinical and radiologic syndrome that represents a common presentation of a diverse group of disorders. The syndrome is characterized by thunderclap headache and reversible vasoconstriction of cerebral arteries, which can either be spontaneous or related to an exogenous trigger. The pathophysiology of reversible cerebral vasoconstriction syndrome is unknown, though alterations in cerebral vascular tone are thought to be a key underlying mechanism. The syndrome typically follows a benign course; however, reversible cerebral vasoconstriction syndrome may result in permanent disability or death in a small minority of patients secondary to complications such as ischemic stroke or intracranial hemorrhage.
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Enfermedades Arteriales Cerebrales/fisiopatología , Arterias Cerebrales/fisiopatología , Cefaleas Primarias/etiología , Cefaleas Primarias/fisiopatología , Vasoconstricción , Adulto , Encéfalo/fisiopatología , Enfermedades Arteriales Cerebrales/diagnóstico , Enfermedades Arteriales Cerebrales/terapia , Femenino , Cefaleas Primarias/diagnóstico , Humanos , Hemorragias Intracraneales/etiología , Pronóstico , Accidente Cerebrovascular/etiología , Síndrome , Vasoespasmo Intracraneal/etiologíaRESUMEN
The diagnostic evaluation of a patient with reversible cerebral vasoconstriction syndrome integrates clinical, laboratory, and radiologic findings. Imaging plays an important role by confirming the presence of cerebral vasoconstriction; monitoring potential complications such as ischemic stroke; and suggesting alternative diagnoses, including CNS vasculitis and aneurysmal subarachnoid hemorrhage. Noninvasive vascular imaging, including transcranial Doppler sonography and MR angiography, has played an increasingly important role in this regard, though conventional angiography remains the criterion standard for the evaluation of cerebral artery vasoconstriction. Newer imaging techniques, including high-resolution vessel wall imaging, may help in the future to better discriminate reversible cerebral vasoconstriction syndrome from primary angiitis of the CNS, an important clinical distinction.
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Neuroimagen/métodos , Vasoespasmo Intracraneal/diagnóstico , Diagnóstico Diferencial , Humanos , MasculinoRESUMEN
BACKGROUND: Clostridium difficile infection (CDI) recurs in 20-30% of patients. AIM: To describe the predictors of recurrence in out-patients with CDI. METHODS: Out-patient cases of CDI in Olmsted County, MN residents diagnosed between 28 June 2007 and 25 June 2010 were identified. Recurrent CDI was defined as recurrence of diarrhoea with a positive C. difficile PCR test from 15 to 56 days after the initial diagnosis with interim resolution of symptoms. Patients who had two positive tests within 14 days were excluded. Cox proportional hazard models were used to assess the association of clinical variables with time to recurrence of CDI. RESULTS: The cohort included 520 out-patients; 104 had recurrent CDI (cumulative incidence of 17.5% by 30 days). Univariate analysis identified increasing age and antibiotic use to be associated with recurrent CDI. Severe CDI, peripheral leucocyte count and change in serum creatinine >1.5-fold were not. In a multiple variable model, concomitant antibiotic use was associated with risk of recurrent CDI (HR = 5.4, 95% CI 1.6-17.5, P = 0.005), while age (HR per 10 year increase = 1.1, 95% CI 0.9-1.3, P = 0.22); peripheral leucocyte count >15 × 10(9) /L (HR = 1.0, 95% CI 0.5-2.1, P = 0.92); and change in serum creatinine greater than 1.5-fold (HR = 0.8, 95% CI 0.4-1.5, P = 0.44) were not. CONCLUSIONS: Antibiotic use was independently associated with a dramatic risk of recurrent Clostridium difficile infection in an out-patient cohort. It is important to avoid unnecessary systemic antibiotics in patients with Clostridium difficile infection, and patients with ongoing antibiotic use should be monitored closely for recurrent infection.
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Antibacterianos/uso terapéutico , Infecciones por Clostridium/epidemiología , Diarrea/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Atención Ambulatoria/estadística & datos numéricos , Niño , Preescolar , Clostridioides difficile/genética , Infecciones por Clostridium/tratamiento farmacológico , Infecciones por Clostridium/genética , Infecciones por Clostridium/microbiología , ADN Bacteriano/análisis , Diarrea/tratamiento farmacológico , Diarrea/microbiología , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Modelos de Riesgos Proporcionales , Recurrencia , Factores de Riesgo , Adulto JovenRESUMEN
Underground structures at shallow depths are often constructed for metro lines, either in loose or dense layered soils. Tunnelling in urban areas is predominantly under surface structures and on tunnelling, innumerable changes in the form of distortion take place in strata surrounding the tunnel. Extent of displacement/damage to buildings or the tunnel-soil structure interaction depends on the type of building and nature of strata. Effect on displacements has been less studied in granular soils compared to other types of soils like clays. In this paper, parametric studies are conducted to find the displacements at surface, in granular soil conditions, due to varying building storeys and building eccentricities from the tunnel centre line. Effect of presence of geosynthetic layer under footings is further studied. Prior to the parametric studies, validity of the model used is checked with field data available for a stretch of tunnel in South India. Results of simulation studies reveal that inclusion of building reduces displacements at the surface in the dense strata. In very dense strata, the displacements increase as compared to the case without a building. As the centre of the building moves away from the tunnel centre line, settlement above the tunnel matches displacements in the case without building. Applicability of 3DEC software is checked with respect to the present study.