Local Environment of Sc and Y Dopant Ions in Aluminum Nitride Thin Films.

The local environments of Sc and Y in predominantly ⟨002⟩ textured, Al1-xDoxN (Do = Sc, x = 0.25, 0.30 or Y, x = 0.25) sputtered thin films with wurtzite symmetry were investigated using X-ray absorption (XAS) and photoelectron (XPS) spectroscopies. We present evidence from the X-ray absorption fine structure (XAFS) spectra that, when x = 0.25, both Sc3+ and Y3+ ions are able to substitute for Al3+, thereby acquiring four tetrahedrally coordinated nitrogen ligands, i.e., coordination number (CN) of 4. On this basis, the crystal radius of the dopant species in the wurtzite lattice, not available heretofore, could be calculated. By modeling the scandium local environment, extended XAFS (EXAFS) analysis suggests that when x increases from 0.25 to 0.30, CN for a fraction of the Sc ions increases from 4 to 6, signaling octahedral coordination. This change occurs at a dopant concentration significantly lower than the reported maximum concentration of Sc (42 mol % Sc) in wurtzite (Al, Sc)N. XPS spectra provide support for our observation that the local environment of Sc in (Al, Sc)N may include more than one type of coordination.

C-Axis Textured, 2-3 µm Thick Al0.75Sc0.25N Films Grown on Chemically Formed TiN/Ti Seeding Layers for MEMS Applications.

A protocol for successfully depositing [001] textured, 2−3 µm thick films of Al0.75Sc0.25N, is proposed. The procedure relies on the fact that sputtered Ti is [001]-textured α-phase (hcp). Diffusion of nitrogen ions into the α-Ti film during reactive sputtering of Al0.75,Sc0.25N likely forms a [111]-oriented TiN intermediate layer. The lattice mismatch of this very thin film with Al0.75Sc0.25N is ~3.7%, providing excellent conditions for epitaxial growth. In contrast to earlier reports, the Al0.75Sc0.25N films prepared in the current study are Al-terminated. Low growth stress (<100 MPa) allows films up to 3 µm thick to be deposited without loss of orientation or decrease in piezoelectric coefficient. An advantage of the proposed technique is that it is compatible with a variety of substrates commonly used for actuators or MEMS, as demonstrated here for both Si wafers and D263 borosilicate glass. Additionally, thicker films can potentially lead to increased piezoelectric stress/strain by supporting application of higher voltage, but without increase in the magnitude of the electric field.

Anomaly Detection for Individual Sequences with Applications in Identifying Malicious Tools.

Anomaly detection refers to the problem of identifying abnormal behaviour within a set of measurements. In many cases, one has some statistical model for normal data, and wishes to identify whether new data fit the model or not. However, in others, while there are normal data to learn from, there is no statistical model for this data, and there is no structured parameter set to estimate. Thus, one is forced to assume an individual sequences setup, where there is no given model or any guarantee that such a model exists. In this work, we propose a universal anomaly detection algorithm for one-dimensional time series that is able to learn the normal behaviour of systems and alert for abnormalities, without assuming anything on the normal data, or anything on the anomalies. The suggested method utilizes new information measures that were derived from the Lempel-Ziv (LZ) compression algorithm in order to optimally and efficiently learn the normal behaviour (during learning), and then estimate the likelihood of new data (during operation) and classify it accordingly. We apply the algorithm to key problems in computer security, as well as a benchmark anomaly detection data set, all using simple, single-feature time-indexed data. The first is detecting Botnets Command and Control (C&C) channels without deep inspection. We then apply it to the problems of malicious tools detection via system calls monitoring and data leakage identification.We conclude with the New York City (NYC) taxi data. Finally, while using information theoretic tools, we show that an attacker's attempt to maliciously fool the detection system by trying to generate normal data is bound to fail, either due to a high probability of error or because of the need for huge amounts of resources.

Privacy-Aware Distributed Hypothesis Testing.

A distributed binary hypothesis testing (HT) problem involving two parties, a remote observer and a detector, is studied. The remote observer has access to a discrete memoryless source, and communicates its observations to the detector via a rate-limited noiseless channel. The detector observes another discrete memoryless source, and performs a binary hypothesis test on the joint distribution of its own observations with those of the observer. While the goal of the observer is to maximize the type II error exponent of the test for a given type I error probability constraint, it also wants to keep a private part of its observations as oblivious to the detector as possible. Considering both equivocation and average distortion under a causal disclosure assumption as possible measures of privacy, the trade-off between the communication rate from the observer to the detector, the type II error exponent, and privacy is studied. For the general HT problem, we establish single-letter inner bounds on both the rate-error exponent-equivocation and rate-error exponent-distortion trade-offs. Subsequently, single-letter characterizations for both trade-offs are obtained (i) for testing against conditional independence of the observer's observations from those of the detector, given some additional side information at the detector; and (ii) when the communication rate constraint over the channel is zero. Finally, we show by providing a counter-example where the strong converse which holds for distributed HT without a privacy constraint does not hold when a privacy constraint is imposed. This implies that in general, the rate-error exponent-equivocation and rate-error exponent-distortion trade-offs are not independent of the type I error probability constraint.

[INTERVENTIONS TO IMPROVE THE QUALITY OF THE INTERNSHIP YEAR].

AIMS: To describe three interventions that have improved the quality of the internship. BACKGROUND: All medical school graduates are required to take a one year internship, rotating through various hospital departments. By various objective and subjective measures, the quality, benefit and efficacy of the internship varies significantly between departments and hospitals and also depends on where the interns studied. METHODS: The interventions were: First, all graduates of foreign medical schools (FMG) were required to interview and present a patient, demonstrating practical knowledge of spoken and written Hebrew and basic medical terminology prior to the start of the internship. Second, on the first day of their internship in internal medicine the new interns participate in an orientation day, addressing multiple clinical, administrative and other components. Third, upon the completion of their rotation in internal medicine, the interns participate in an interactive session to help them prepare for their future career. RESULTS: First, during the first 3 years after introducing the Hebrew test, 101 FMGs took the test, 89 (88%) passed the first time, the remainder passed the 2nd or 3rd test after another 1-3 months of studying Hebrew. Of 31 women, 30 (97%) passed the first time, compared to 59/70 (84%) of the men (p=0.065); 27/28 (96%) of Jewish interns passed the first time compared to 62/73 (85%) non-Jewish interns (p=0.99). Physicians report on the significantly increased ability of FMGs to participate in all activities from the onset of their internship. Second, upon completion of the orientation, 137 interns provided feedback of its 12 components; satisfaction was marked on a Likert scale (ranging from 1 [low] to 5 [high]) and ranged from 4.2±0.1 to 4.7±0.6; high/very high satisfaction with the various components ranged from 79% to 96%. Third, feedback was provided by 96 interns after participating in the interactive session helping to prepare for the future; satisfaction with the 5 components of the session ranged from 3.8±0.8 (on the acquired insight into the possibilities, scope and limitations regarding their future career) to 4.5±0.7 (regarding the relevance of such sessions). Sub-analysis revealed several statistically significant differences between male and female interns (male interns indicated these sessions to be more important to them than females, p<0.01), and FMG (as compared to graduates from Israeli medical schools) indicated that they had acquired relevant information more often (p<0.001). CONCLUSIONS: Various interventions positively impact the quality, benefit and efficacy of the internship as observed by physicians working with the residents, as well as perceived by the interns themselves.

Overuse and Underuse of Visual Field Testing Over 15 Years.

PRéCIS:: A 15-year analysis of 198,843 visual field (VF) tests revealed a growing trend for their performance for nonglaucoma indications. Adherence to glaucoma management guidelines was suboptimal. Guidelines for referral to VF assessments should be established. PURPOSE: The purpose of this study was to identify trends in VF assessments over 15 years among patients with and without suspected or confirmed glaucoma, in a large healthcare maintenance organization. METHODS: This was a population-based retrospective cohort study, conducted by means of electronic medical database analyses. STUDY POPULATION: Maccabi Healthcare Services is an healthcare maintenance organization that insures 2 million members constituting 25% of the population. All members who underwent at least 1 VF test between January 2000 and December 2014 were included. In addition, all members with glaucoma or suspected glaucoma diagnosis or who were prescribed with antiglaucoma medications were evaluated. MAIN OUTCOME MEASURES: VF performance rates. RESULTS: A total of 93,617 Maccabi Healthcare Services members underwent 198,843 VF tests; of whom 47.9% involved patients without any glaucoma-related conditions. There was a growing trend over time toward more of those members to undergo VF tests and, by 2014, non-glaucoma-related members comprised 74.0% of new VF assessments. In contrast, 32.3% of glaucoma-related patients did not perform even 1 VF test throughout the entire study period. Although over 2 years (25.95±6.33 mo) passed between the first glaucoma-related diagnosis and first VF test, once a patient underwent the first VF test, an average once-a-year VF follow-up (0.95±0.37 annual tests) began. CONCLUSION: There is a growing trend for VF tests being apparently overused for indications other than glaucoma. Concurrently, adherence to glaucoma management guidelines on VF tests is suboptimal, leading to discernible underuse. Guidelines for VF assessments in nonglaucoma patients should be established. Adherence to existing glaucoma management guidelines should be improved.

Statin Therapy: Diabetes Mellitus Risk and Cardiovascular Benefit in Primary Prevention.

BACKGROUND: The salutary effects of statin therapy in patients with cardiovascular disease (CVD) are well established. Although generally considered safe, statin therapy has been reported to contribute to induction of diabetes mellitus (DM). OBJECTIVES: To assess the risk-benefit of statin therapy, prescribed for the prevention of CVD, in the development of DM. METHODS: In a population-based real-life study, the incidence of DM and CVD were assessed retrospectively among 265,414 subjects aged 40-70 years, 17.9% of whom were treated with statins. Outcomes were evaluated according to retrospectively determined baseline 10 year cardiovascular (CV) mortality risks as defined by the European Systematic COronary Risk Evaluation, statin dose-intensity regimen, and level of drug adherence. RESULTS: From 2010 to 2014, 5157 (1.9%) new cases of CVD and 11,637 (4.4%) of DM were observed. Low-intensity statin therapy with over 50% adherence was associated with increased DM incidence in patients at low or intermediate baseline CV risk, but not in patients at high CV risk. In patients at low CV risk, no CV protective benefit was obtained. The number needed to harm (NNH; incident DM) for low-intensity dose regimens with above 50% adherence was 40. In patients at intermediate and high CV risk, the number needed to treat was 125 and 29; NNH was 50 and 200, respectively. CONCLUSIONS: Prescribing low-dose statins for primary prevention of CVD is beneficial in patients at high risk and may be detrimental in patients at low CV risk. In patients with intermediate CV risk, our data support current recommendations of individualizing treatment decisions.

Utilization of ultrasonography to detect developmental dysplasia of the hip: when reality turns selective screening into universal use.

BACKGROUND: Developmental dysplasia of the hip (DDH) occurs in 3-5 of 1000 live births and is associated with known risk factors. In most countries, formal practice for early detection of DDH entails the combination of risk factor identification and physical examination of the hip, while the golden standard diagnostic instrument is hip ultrasonography (US). This practice is commonly referred to as selective screening. Infants with positive US findings are treated with a Pavlik harness, a dynamic abduction splint. The objective of our study was to evaluate hip US utilization patterns in Maccabi Healthcare Services (MHS), a large health plan. METHODS: Study population: All MHS members, born between June 2011 and October 2014, who underwent at least one US before the age of 15 months. STUDY VARIABLES: Practice specialty and number of enrolled infants. Positive US result was defined as referral to an abduction splint. Cost was based on Ministry of Health price list. Chi square and correlation coefficients were employed in the statistical analysis. RESULTS: Of the 115,918 infants born during the study period, 67,491 underwent at least one hip US. Of these, 60.6% were female, mean age at performance: 2.2 months. Of those who underwent US, 625 (0.93%) were treated with a Pavlik harness: 0.24% of the male infants and 1.60% of the female infants (p < 0.001). Analysis of physician practice characteristics revealed that referral to US was significantly higher among pediatricians as compared with general practitioners (60% and 35%, respectively). Practice volume had no influence on referral rate. Direct medical costs of the 107 hip US examinations performed that led to detection of one positive case (treated by Pavlik): US$10,000. CONCLUSIONS: Current pattern of hip US utilization for early detection of DDH resembles universal screening more closely than selective screening. This can inform policy decisions as to whether a stricter selective screening or a formal move to universal screening is appropriate in Israel.

Surfactant-induced phases in water-supported alkane monolayers: I. Thermodynamics.

Alkanes longer than n = 6 carbons do not spread on the water surface, but condense in a macroscopic lens. However, adding trimethylammonium-based surfactants, C(m)TAB, in submillimolar concentrations causes the alkanes to spread and form a single Langmuir-Gibbs (LG) monolayer of mixed alkanes and surfactant tails, which coexists with the alkane lenses. Upon cooling, this LG film surface-freezes at a temperature T(s) above the bulk freezing temperature T(b). The thermodynamics of surface freezing (SF) of these LG films is studied by surface tension measurements for a range of alkanes (n = 12-21) and surfactant alkyl lengths (m = 14, 16, 18), at several concentrations c. The surface freezing range T(s)-T(b) observed is up to 25 °C, an order of magnitude larger than the temperature range of SF monolayers on the surface of pure alkane melts. The measured (n,T) surface phase diagram is accounted for well by a model based on mixtures' theory, which includes an interchange energy term ω. ω is found to be negative, implying attraction between unlike species, rather than the repulsion found for SF of binary alkane mixtures. Thus, the surfactant/alkane mixing is a necessary condition for the occurrence of SF in these LG films. The X-ray derived structure of the films is presented in an accompanying paper.

Predictors of blood pressure control among hypertensives in community health centers.

BACKGROUND: The correlates of blood pressure (BP) control among hypertensive individuals who have access to care in community-based health-care settings are poorly characterized, particularly among minority and immigrant populations. METHODS: Using data extracted from electronic medical records in four federally qualified health centers in New York, we investigated correlates of hypertension (HTN) control in cross-sectional analyses. The sample consisted of adult, nonobstetric patients with a diagnosis of HTN and a clinic visit between June 2007 and October 2008 (n = 2,585). RESULTS: Forty-nine percent of hypertensive patients had controlled BP at their last visit. Blacks had a higher prevalence of HTN (B, 32.8%; W, 16.2%; H, 11.5%) and were less likely to have controlled BP (B, 42.2%; W, 50.9%; H, 50.8%) compared with Hispanics and whites. Medication intensification did not differ by race/ethnicity. In multivariate analyses higher body mass index (BMI), black race, diabetes, fewer clinical encounters, and male gender were associated with poor BP control. However, when we applied the Seventh Report of the Joint National Committee (JNC 7) definition for BP control for nondiabetic patients (systolic blood pressure (SBP) <140, diastolic blood pressure (DBP) <90) to all patients with HTN, we found no difference in BP control between those with and without diabetes. CONCLUSIONS: Blacks had poorer HTN control compared with whites and Hispanics. Significant discrepancies in BP control between hypertensive patients with and without diabetes may be related to a lack of provider adherence to JNC 7 guidelines that define BP control in this population as <130/80. Further research is needed to understand racial disparities in BP control as well as factors influencing clinician's management of BP among patients with diabetes.

Technology-driven intervention to improve hypertension outcomes in community health centers.

OBJECTIVES: To assess the impact of an electronic medical record (EMR) with clinical decision support (CDS) and performance feedback on provider adherence to guideline-recommended care and blood pressure (BP) control compared with a standard EMR alone. STUDY DESIGN: Quasi-experimental with repeated measures. METHODS: The study was conducted in a 4-site, federally qualified health center, Open Door Family Medical Centers, located in New York. The research team, Open Door leadership, providers, and staff developed and implemented a tailored multicomponent CDS system, which included a BP alert, a hypertension (HTN) order set, an HTN template, and clinical reminders. We extracted patient-level data for each encounter 17 months prior to implementation of the intervention (June 2007-October 2008) and 15 months post-intervention (April 2009-June 2010), from the EMR's data tables for all adult nonobstetric patients with a diagnosis of HTN (N = 3636). RESULTS: Rates of HTN control were significantly greater in the post-intervention period compared with the baseline period (50.9% vs 60.8%; P <.001). Process measures, derived from the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure Guidelines, also improved significantly. Logistic regression with generalized estimating equations showed that patients were 1.5 times more likely to have controlled BP post-intervention than pre-intervention. Correlates of poor BP control were black race, higher body mass index, diabetes, female gender, income, and a greater number of prescribed antihypertensive medications. CONCLUSIONS: Our findings suggest that health information technology that is implemented as part of a multicomponent quality improvement initiative can lead to improvements in HTN care and outcomes.