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A robust biomedical informatics infrastructure is essential for academic health centers engaged in translational research. There are no templates for what such an infrastructure encompasses or how it is funded. An informatics workgroup within the Clinical and Translational Science Awards network conducted an analysis to identify the scope, governance, and funding of this infrastructure. After we identified the essential components of an informatics infrastructure, we surveyed informatics leaders at network institutions about the governance and sustainability of the different components. Results from 42 survey respondents showed significant variations in governance and sustainability; however, some trends also emerged. Core informatics components such as electronic data capture systems, electronic health records data repositories, and related tools had mixed models of funding including, fee-for-service, extramural grants, and institutional support. Several key components such as regulatory systems (e.g., electronic Institutional Review Board [IRB] systems, grants, and contracts), security systems, data warehouses, and clinical trials management systems were overwhelmingly supported as institutional infrastructure. The findings highlighted in this report are worth noting for academic health centers and funding agencies involved in planning current and future informatics infrastructure, which provides the foundation for a robust, data-driven clinical and translational research program.
Differences between verbal and non-verbal cognitive development from childhood to adulthood may differentiate between those with and without psychotic symptoms and affective symptoms in later life. However, there has been no study exploring this in a population-based cohort.
The sample was drawn from the MRC National Survey of Health and Development, and consisted of 2384 study members with self-reported psychotic experiences and affective symptoms at the age of 53 years, and with complete cognitive data at the ages of 8 and 15 years. The association between verbal and non-verbal cognition at age 8 years and relative developmental lag from age 8 to 15 years, and both adult outcomes were tested with the covariates adjusted, and mutually adjusted for verbal and non-verbal cognition.
Those with psychotic experiences [thought interference (n = 433), strange experience (n = 296), hallucination (n = 88)] had lower cognition at both the ages of 8 and 15 years in both verbal and non-verbal domains. After mutual adjustment, lower verbal cognition at age 8 years and greater verbal developmental lag were associated with higher likelihood of psychotic experiences within individuals, whereas there was no association between non-verbal cognition and any psychotic experience. In contrast, those with case-level affective symptoms (n = 453) had lower non-verbal cognition at age 15 years, and greater developmental lag in the non-verbal domain. After adjustment, lower non-verbal cognition at age 8 years and greater non-verbal developmental lag were associated with higher risk of case-level affective symptoms within individuals.
These results suggest that cognitive profiles in childhood and adolescence differentiate psychiatric disease spectra.
The legal environment may improve response willingness among local health department (LHD) workers. We examined whether 3 hypothetical legal protections influence LHD workers’ self-reported response willingness for 4 emergency scenarios and whether specific demographic factors are associated with LHD workers’ response willingness given these legal protections.
Our 2011–2012 survey included questions on demographics and about attitudes and beliefs regarding LHD workers’ willingness to respond to 4 emergency scenarios given specific legal protections (i.e., ensuring priority health care for workers’ families, granting workers access to mental health services, and guaranteeing access to personal protective equipment). Data were collected from 1238 LHD workers in 3 states.
Across scenarios, between 60% and 83% of LHD workers agreed that they would be more willing to respond given the presence of 1 of the 3 hypothetical legal protections. Among the 3 legal protections, a guarantee of personal protective equipment elicited the greatest agreement with improved response willingness.
Specific legal protections augment a majority of LHD workers’ response willingness. Policymakers must, however, balance improved response willingness with other considerations, such as the ethical implications of prioritizing responders over the general public. (Disaster Med Public Health Preparedness. 2015;9:98–102)
For effective responses to emergencies, individuals must have the ability to respond and also be willing to participate in the response. A growing body of research points to gaps in response willingness among several occupational cohorts with response duties, including the Emergency Medical Services (EMS) workforce. Willingness to respond is particularly important during an influenza or other pandemic, due to increased demands on EMS workers and the potential for workforces to be depleted if responders contract influenza or stay home to care for sick dependents. State emergency preparedness laws are one possible avenue to improve willingness to respond.
Presence of certain state-level emergency preparedness laws (ie, ability to declare a public health emergency; requirement to create a public health emergency plan; priority access to health resources for responders) is associated with willingness to respond among EMS workers.
Four hundred twenty-one EMS workers from the National Registry of Emergency Medical Technicians’ (NREMT's) mid-year Longitudinal EMT Attributes and Demographics Study (LEADS) were studied. The survey, which included questions about willingness to respond during an influenza pandemic, was fielded from May through June 2009. Survey data were merged with data about the presence or absence of the three emergency preparedness laws of interest in each of the 50 US states. Unadjusted logistic regression analyses were performed with the presence/absence of each law and were adjusted for respondents’ demographic/locale characteristics.
Compared to EMS workers in states that did not allow the government to declare a public health emergency, those in states that permitted such declarations were more likely to report that they were willing to respond during an influenza pandemic. In adjusted and unadjusted analyses, this difference was not statistically significant. Similar results were found for the other state-level emergency preparedness laws of interest.
While state-level emergency preparedness laws are not associated with willingness to respond, recent research suggests that inconsistencies between the perceived and objective legal environments for EMS workers could be an alternative explanation for this study's findings. Educational efforts within the EMS workforce and more prominent state-level implementation of emergency preparedness laws should be considered as a means to raise awareness of these laws. These types of actions are important steps toward determining whether state-level emergency preparedness laws have the potential to promote response willingness among EMS workers.
RutkowL, VernickJS, ThompsonCB, PirralloRG, BarnettDJ. Emergency Preparedness Law and Willingness to Respond in the EMS Workforce. Prehosp Disaster Med. 2014;29(4):1-6.
For optical fields the notion of a total angular momentum has long been known. The concept of a light beam carrying orbital angular momentum, however, was unfamiliar until it was discovered that Laguerre-Gaussian beams, within the paraxial approximation, carry a well-defined orbital angular momentum [1, 2]. This discovery started the modern interest in orbital angular momentum of light. In this chapter we discuss the theoretical framework of orbital angular momentum of light in terms of fields and light beams and how to generate these. The material in this chapter is based in parts on the PhD thesis of Götte .
A quantitative treatment of the mechanical effects of light became possible only after light had been integrated into Maxwell's dynamical theory of electromagnetic waves. With this theory Poynting  derived a continuity equation for the energy in the electromagnetic field. After Heaviside [5, 6] introduced the vectorial notation for the Maxwell equations this continuity equation could be written in its modern form using the Poynting vector. Interestingly, the linear momentum density in the electromagnetic field is also given by the Poynting vector apart from constant factors depending on the chosen system of units. Poynting  also derived an expression for the angular momentum of circularly polarised light by means of a mechanical analogue in the form of a rotating shaft. Later, Poynting's expression was verified by measuring the torque on a quarter wave-plate due to circularly polarised light .
The quantum mechanical description of the azimuthal rotation angle and the orbital angular momentum around the polar axis differs greatly from the description of position and momentum. This has led to a controversy over the existence of a self-adjoint angle operator in the literature. It is possible to circumvent the problems of defining a self-adjoint operator for a periodic variable by using trigonometric functions of operators as a basis for the quantum mechanical description. This approach, however, does not allow us to study the properties of the angle operator itself. By using a state space of an arbitrarily large yet finite number of dimensions, it is possible to introduce angle and orbital angular momentum as a conjugate pair of variables both represented by Hermitian matrices. After physical and measurable quantities have been calculated in this state space the number of dimensions is allowed to tend to infinity in a limiting procedure.
The first part of this chapter reviews the difficulties associated with the quantum mechanical formulation of angle and orbital angular momentum and presents a way to overcome these problems using a finite-dimensional state space. In the second part this formulation is generalised to include the phenomenon of non-integer orbital angular momentum. This part is based on a chapter of the PhD thesis of Götte , where further details may be found.
The correct description of a periodic variable such as a rotation angle or the optical phase has been a long standing problem in quantum mechanics. At the root of the problem is the question of whether the variable itself is restricted in a 2π radian range or whether it evolves continuously without bound.
The aim of this study was to estimate the amount of childhood hepatitis B virus transmission in children born in the UK, a very low-prevalence country, that is preventable only by universal hepatitis B immunization of infants. Oral fluid specimens were collected from schoolchildren aged 7–11 years in four inner city multi-ethnic areas and tested for the presence of antibody to hepatitis B core antigen (anti-HBc). Those found positive or indeterminate were followed up with testing on serum to confirm their hepatitis B status. The overall prevalence of anti-HBc in children was low [0·26%, 95% confidence interval (CI) 0·14–0·44]. The estimated average annual incidence of hepatitis B was estimated to be 29·26/100 000 children (95% CI 16·00–49·08). The total incidence that is preventable only by a universal infant immunization programme in the UK was estimated to be between 5·00 and 12·49/100 000. The study demonstrates that the extent of horizontal childhood hepatitis B virus transmission is low in children born in the UK and suggests that schools in the UK are an uncommon setting for the transmission of the virus. Targeted hepatitis B testing and immunization of migrants from intermediate- and high-prevalence countries is likely to be a more effective measure to reduce childhood transmission than a universal infant immunization programme.
We have demonstrated a uniform, robust interface for high-k deposition with significant improvements in device electrical performance compared to conventional surface preparation techniques. The interface was a thin thermal oxide that was grown and then etched back in a controlled manner to the desired thickness. Utilizing this approach, an equivalent oxide thickness (EOT) as low as 0.87 nm has been demonstrated on high-k gate stacks having improved electrical characteristics as compared to more conventionally prepared starting surfaces.
Si-Si(B) doping superlattices (pipi structures) were grown by MBE and studied using double crystal x-ray diffraction and SIMS. Detailed analysis of the complex x-ray rocking curves required comparison of experimental data with theoretically simulated data. It is demonstrated that this technique is sensitive to irregularities in the dopant composition, dopant distribution and superlattice period. The B concentration profile is shown to spread well into the intrinsic layers and the extent and magnitude of the dopant distribution has been quantified. A comparison of this data with SIMS showed good agreement for the distribution of B and reasonable agreement for the peak values of B concentration.
Recent results on metastable semiconducting alloys, concerning in particular the growth of new Sn-based alloys (GaSb)1−x(Sn2)x and Gel−xSnx and the physical properties of (GaAs)1−x(Ge2)x and (GaSb)1−x(Ge2)x, are discussed. (GaSb)1−x(Sn2)x and Ge1−xSnx alloy films were grown with x-values as high as 0.20 and 0.15, respectively, well in excess of equilibrium Sn solid solubility limits (<1%) while epitaxial (GaAs)1−x(Ge2) and (GaSb)1−x(Ge2)x alloys were obtained on (100) GaAs at compositions ranging across the pseudobinary phase diagram. Low energy ion bombardment induced collisional mixing and preferential sputtering during film growth played a critical role in obtaining single phase alloys. An optimal ion energy, which depended on the ion flux and the alloy composition, was determined, allowing in most cases growth at temperatures T, sufficient for obtaining single crystal alloys on (100) GaAs and (100) Ge substrates. Decomposition of the Sn-based alloys occurred above a critical Ts- value via α-Sn-rich precipitates which were stable above the β-Sn melting point. X-ray diffraction, STEM, EXAFS, and Raman spectroscopy measurements, performed on single crystal (GaAs)1−x(Ge2)x and (GaSb)1−x(Ge2)x alloys, indicate that there is a transition in the long-range order from zincblende to diamond with increasing x while the short-range order remains perfect at all compositions, i.e. no V-V or III-Ill bonds are observed. These results are discussed in light of recent models which relate (GaAs)1−x(Ge2)x atomic structure to its band structure and optical properties.
The reactions of metal oxides including CuO, ZnO, V2O5, and PbO with 1,1,1,5,5,5-hexaflouro- 2,4-pentanedione (hfacH) were investigated. A hot-wall reactor was used to react hfacH with metal oxide powders to form sufficient quantities of volatile reaction products for characterization by Infrared Spectroscopy (IR), Elemental Analysis (EA), Nuclear Magnetic Resonance (NMR), Mass Spectroscopy (MS), Thermogravimetric Analysis and Differential Thermal Analysis (DTA). PbO, ZnO and CuO powders reacted rapidly at 200 °C to form the corresponding metal β-diketonates and V2O5 reacted to give OV(hfac)2. A differential cold-wall reactor was to used to measure etch rates of CuOx films as a function of temperature and hfacH partial pressure. AES and XPS analysis of the laser ablation deposited CuOx film annealed in an O2 atmosphere revealed that the film was composed of CuO and Cu2O. Etch rates of up to a I l.βm/min at hfacH partial pressure of 1 Torr at 270 °C were obtained. Laser induced etching of the same CuOx film with hfacH showed evidence of copper oxide removal.
HI/H2/Ar discharges are shown to be universal etchants for rn-V semiconductors, giving rise to highly anisotropic features with smooth surface morphologies. At loy dc self bia:s (-100V) and low pressure (1 mTorr), etch rates for all III-V materials of >2000Å min−1 are possible for high HI percentages in the discharges, whereas rates greater than 1 Åm min−1 are obtained at higher pressures and dc biases. These etch rates are approximately an order of magnitude faster than for CH4/H2/Ar mixtures under the same conditions and there is no polymer deposition on the mask or within the reactor chamber with HI/H2/Ar. Auger Electron Spectroscopy reveals residue-free, stoichiometric surfaces after dry etching in this mixture. As i result, photoluminescence intensities from dry etched samples remain high with little apparent damage introduction. Changes in the near-surface carrier concentration due to hydrogen passivation effects are also negligible with HI-based mixtures in comparison to CH4-based dry etching.
This paper describes a novel route for removal of surface carbon from heavy-metal fluoride glasses melted in vitreous carbon crucibles. The technique utilizes dry etching with active fluorine produced in a NF3 plasma generated in a microwave cavity.
Ionising radiations have been observed to produce significant improvements in thin film adhesion by several experimental groups. We present the results of an exhaustive and conclusive series of experiments on the effect of clean processing and heavy ion irradiation on the adhesion of metal films to substrates of silicon and tantalum. The experiments were performed in a unique research-scale Ultra High Vacuum Cluster tool, to gain control of the all important surface and interface compositions.
Our results show that adhesion is greatest for films deposited on atomically clean surfaces. Such films adhere better than conventionally deposited films subjected to a post deposition irradiation treatment. Clean processed samples show no benefit from subsequent radiation processing. Our results are consistent with the radiation enhanced adhesion phenomenon being due to the radiolysis of interfacial contaminant layers, producing an interface with lower interfacial energy and hence better bonding. Where adhesion enhancement is observed, the process is consistent with a semi-empirical model of the process using an activation energy of some 5 eV per atom.
Low temperature Si and Si1−xGex epitaxy is one of the major thrusts in the trend towards low temperature Si processing for future generation ULSI circuits and novel Si-based devices. A remote plasma-enhanced chemical vapor deposition (RPCVD) technique has been developed to achieve Si homoepitaxy and Si1−xGex heteroepitaxy at low temperatures (≤450'C). P-type films have been grown by introducing 90 ppm or 5000 ppm B2H6/He into the system during the growth process to achieve in situ electrically active boron doping. A mesa diode structure with minimal thermal budget in the fabrication process has been employed to evaluate the properties of the boron-doped Si and Si1−xGex films grown at 450°C by RPCVD. Leakage current densities are reduced for diodes grown at 14–18 W (40–50 Å/min. growth rates) compared to similar devices grown at 6.6 W (5 Å/min.). N-type films have been grown by the introduction of 50 ppm PH3/He. Secondary ion mass spectroscopy (SIMS) has been employed to analyze the boron and phosphorus incorporation efficiencies and doping profiles under different conditions. Boron and phosphorus doping profile transitions as sharp as 50–100 Å/decade have been achieved. Transmission electron microscopy (TEM) has been used to investigate the microstructure of the B-doped films.