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Hearing loss affects over 1.3 billion individuals worldwide, with the greatest burden among adults. Little is known regarding the association between adult-onset hearing loss and employment.
Seven databases (PubMed, Embase, Cochrane Library, ABI/Inform Collection, Business Source Ultimate, Web of Science and Scopus) were searched through to October 2018. The key word terms used related to hearing loss and employment, excluding paediatric or congenital hearing loss and deaf or culturally deaf populations.
The initial search resulted in 13 144 articles. A total of 7494 articles underwent title and abstract screening, and 243 underwent full-text review. Twenty-five articles met the inclusion criteria. Studies were set in 10 predominantly high-income countries. Seven of the 25 studies analysed regionally or nationally representative datasets and controlled for key variables. Six of these seven studies reported associations between hearing loss and employment.
The highest quality studies currently available indicate that adult-onset hearing loss is associated with unemployment. However, considerable heterogeneity exists, and more rigorous studies that include low- and middle-income countries are needed.
In this paper we are concerned with a model in econophysics, the subfield of statistical physics that applies concepts from traditional physics to economics. Our model is an example of an interacting particle system with disorder, meaning that some of the transition rates are not identical but rather drawn from a fixed distribution. Economical agents are represented by the vertices of a connected graph and are characterized by the number of coins they possess. Agents independently spend one coin at rate one for their basic need, earn one coin at a rate chosen independently from a distribution ϕ, and exchange money at rate µ with one of their nearest neighbors, with the richest neighbor giving one coin to the other neighbor. If an agent needs to spend one coin when his/her fortune is at 0, he/she dies, i.e. the corresponding vertex is removed from the graph. Our first results focus on the two extreme cases of lack of cooperation µ=0 and perfect cooperation µ = ∞ for finite connected graphs. These results suggest that, when overall the agents earn more than they spend, cooperation is beneficial for the survival of the population, whereas when overall the agents earn less than they spend, cooperation becomes detrimental. We also study the infinite one-dimensional system. In this case, when the agents earn less than they spend on average, the density of agents that die eventually is bounded from below by a positive constant that does not depend on the initial number of coins per agent or the level of cooperation.
Introduction/Innovation Concept: In 2014, Eastern Ontario paramedic services, their medical director staff and area community colleges developed an EMS Boot Camp experience to orient Queen’s University and the University of Ottawa emergency medicine residents to the role of paramedics and the challenges they face in the field. Current EMS ride-alongs and didactic classroom sessions were deemed ineffective at adequately preparing residents to provide online medical control. From those early discussions came the creation of a real-world, real-time (RWRT) educational experience. Methods: Specific challenges unique to paramedicine are difficult to communicate to a medical control physician at the other end of a telephone. The goal of this one-day educational experience is for residents to gain insight into the complexity and time sensitive nature of delivering medical care in the field. Residents are immersed as responding paramedics in a day of intense RWRT simulation exercises reflecting the common paramedic logistical challenges to delivering patient care in an uncontrolled and dynamic environment. Curriculum, Tool, or Material: Scenarios, run by paramedic students, are overseen by working paramedics from participating paramedic services. Residents learn proper use of key equipment found on an Ontario ambulance while familiarize themselves with patient care standards and medical directives. Scenarios focus on prehospital-specific clinical care issues; performing dynamic CPR in a moving vehicle, extricating a bariatric patient with limited personnel, large scale multi-casualty triage as well as other time sensitive, high risk procedures requiring online medical control approval (i.e. chest needle thoracostomy). Conclusion: EMS Boot Camp dispels preconceived biases regarding “what it’s really like” to deliver high quality prehospital clinical care. When providing online medical control in the future, the residents will be primed to understand and expect certain challenges that may arise. The educational experience fosters collaboration between prehospital and hospital-based providers. The sessions provide a reproducible, standardized experience for all participants; something that cannot be guaranteed with traditional EMS ride-alongs. Future sessions will evaluate participant satisfaction and self-efficacy with the use of a standard evaluation form including pre/post self-evaluations.
The symmetry properties of many inorganic two-dimensional monolayer crystals make them piezoelectric, whereas their three-dimensional parent crystals are not. The emergence of piezoelectricity in the single-layer limit points toward intriguing electromechanical effects and applications in the single- or few-layer regime. We use density functional theory to calculate the piezoelectric coefficients of BN, MoS2, MoSe2, MoTe2, WS2, WSe2 and WTe2. These coefficients are found to be comparable to, and in some cases greater than those of commonly used wurtzite piezoelectrics. The centrosymmetry of a BN bilayer prevents a piezoelectric effect for this structure. However, by developing an elastic model, we find that the bilayer exhibits an unusual electromechanical coupling to the curvature, similar to that of a bimorph. A BN bilayer is found to amplify the constituent monolayers’ in-plane piezoelectric displacements by factors on the order of 103-104 into out-of plane deflections.
AIDA (Asteroid Impact and Deflection Assessment) is a project of a joint mission demonstration of asteroid deflection and characterisation of the kinetic impact effects. It involves the Johns Hopkins Applied Physics Laboratory (with support from members of NASA centers including Goddard Space Flight Center, Johnson Space Center, and the Jet Propulsion Laboratory), and the European Space Agency (with support from members of the french CNRS/Cte dAzur Observatory and the german DLR). This assessment will be done using a binary asteroid target. AIDA consists of two independent but mutually supporting mission concepts, one of which is the asteroid kinetic impactor and the other is the characterisation spacecraft. The objective and status of the project will be presented.
It has been reported  that microwave radiation can enhance many of the mechanical properties of Bombyx mori silkworm cocoon silk, as measured in constant strain rate tensile tests to failure and in stress relaxation tests. The consequences of microwave radiation will affect decisions about the use of silk in settings subjected to significant microwave exposure – for example, as a reinforcing fiber in an epoxy matrix composite that may be microwave cured, or as a component in aircraft radomes.
There are two possible mechanisms by which microwave radiation may affect a material : (i) the radiation may enable chemical and/or microstructural changes – and therefore property changes – in the same way that conventional heating would, or (ii) the high heating rates that are achievable by microwaving may selectively favor changes that would be masked under conventional conditions, where heating rates are low enough to give preference to changes that have a lower activation energy. Here we explore the former possibility for silk.
We characterized several mechanical properties of degummed and subsequently annealed B. mori silk, and compared them to the corresponding properties of degummed B. mori silk that was not annealed. The annealing treatment was carried out at 140 °C for 7 hours (conditions that optimally increased crystal size in an unrelated study of B. mori silk ), and then the fibers were allowed to cool gradually to room temperature over the course of an hour. Comparison of mechanical properties revealed no differences between the materials that we tested. Thus, for annealed silk, we do not observe the enhancements that can be achieved by microwaving. We conclude that in cases where microwaving affects the properties of silk, those changes are not a simple consequence of annealing by the microwaves.
A CMOS integrated microelectrode array (IMA) utilizing a low-inpedance transimpedance input has been developed. The design uses a three-stage amplifier, including a transimpedance input stage, buffer, and multiplexor. The input stage presents a low impedance which provides bias for the neural input and maximizes the current transfer into the circuit. The amplifiers are replicated in an 8x8 array, enabling measurement of a network of 64 neurons invitro. The chip was post-processed to provide a bio-compatible gold interface between the electrodes and the neurons. Simulations and experimental results demonstrate the functionality of the new design. Additional measurements are underway to provide experimental confirmation of the system with in-vitro neurons.
We report on the growth and magnetic properties of single crystal Mn-doped GaN, InGaN, and AlGaN films. The III-Nitride films were grown by MOCVD, while the Mn doping was performed by solid-state diffusion of a surface Mn layer deposited by pulsed laser ablation. Mn-doped InxGa1-xN films were grown with x < 0.15, where the easy axis of magnetization rotates from in-plane to out-of-plane by changing the InxGa1-xN thickness/strain-state of the film from compressively strained to relaxed. Mn-doped AlxGa1-xN films were grown with x < 0.40 showing ferromagnetic behavior above room temperature. SQUID measurements ruled out superparamagnetism within these films. By optimizing the growth and annealing conditions of Mn-doped III-Nitrides, we have achieved Curie temperatures in the range of 228 to 500K. These ferromagnetic Mn-doped III-Nitride films exhibit hysteresis with a coercivity of 100–500 Oe. TEM analysis showed no secondary phases within these films.
Olivines from igneous rocks generally have low calcium contents. However, olivines crystallized from strongly silica-undersaturated magmas occasionally contain large amounts of kirschsteinite (Ki" CaFeSiO4) and monticellite (Mo: CaMgSiO4) components. The purpose of this note is to report the first natural occurrence of kirschsteinite crystals that have lamite (La: CazSiO4) in the mineralogical norm.
Silicon-based polymers with σconjugated electrons have specific properties; photoreactivity for microlithography and photoconductivity for hole transport materials. To explore the possibility of combining these two properties to develop photoresists with electronic transport capability, photoconductivity of polysilanes is investigated in connection with their photoinduced chemical modification. Increase in photocurrent is observed accompanying photoreaction of poly(dimethylsilane) vacuum deposited films. This increase is found to be greatly enhanced in oxygen atmosphere. Such changes of photocurrent can be explained by charge transfer to electron acceptors from Si dangling bonds postulated to be formed during photoreaction.
The ferroelectric (Pb, La) (Zr,Ti)03 (PLZT(9.4/65/35)) optical waveguiding thin films have been prepared on SiO2 coated Si and on silica glass substrates by pulsed laser deposition. X-ray θ–2θ scans revealed that the films are single-phase pseudo-cubic perovskite. The surface chemical composition of the as grown films were determined by XPS. The ferroelectric properties of the films as grown on Pt/Ti coated silicon were demonstrated by using a modified Sawyer-Tower circuit, and the optical waveguiding properties of the films were characterized by using a rutile prism coupling method. The as grown films have an average transmittance of 80% in the wavelength range of 400˜2000nm and a refractive index of 2.2 at 632.8mn close to the bulk PLZT. The distinct m-lines of the guided TM and TE modes of the films as grown on SiO2 coated Si substrates have been observed.
This paper presents the process and experimental results about the improved initial bonding between #7740 glass and silicon wafers. We employed a modified initial bonding procedure, called by water-enhanced direct bonding(WDB) technique, and could obtain large initially-bonded area(≥ 95% of the whole wafer area) at room temperature and high interface energy (≥ 2,000 erg/cm2) through 250 °C post-annealing even though the glass wafer had high surface roughness. The main factors contributing to the wider bonded area and higher interface energy in the developed WDB process could be inferred the increase of chemical species (oxygen and hydroxyl groups) responsible for initial hydrogen bonding and conversion from hydroxyl bonds to siloxane bonds in the temperature range between room temperature and 250 °C.
In this work, we proposed a direct bonding method using interlayers for single crystalline silicon wafers and glass wafers. Various materials were used for interlayers of thermal oxide, sputtered nitride, electron-beam(E-beam) evaporated silicon oxide and molybdenum. After hydrophilization, samples were spin dried and mated together without external forces. Three types of solutions were used for hydrophilizing the samples. Changes of average surface roughness after hydrophilization of the single crystalline silicon wafer, thermal oxide and E-beam silicon-oxide were inspected using atomic force microscope(AFM). Bonding interfaces of the bonded pairs were observed by scanning electron microscope(SEM). Voids and non-contact areas of the bonding pairs were also inspected using infrared(IR) transmission microscope. Surface energy, tensile strength measurements and breaking tests were also done.
A silicon-to-silicon anodic bonding process using a glass layer deposited by electron beam evaporation will be described. Corning #7740 Pyrex glass was used the source material of electron evaporation. From Auger electron spectroscopy (AES), the composition of the deposited glass layer is nearly same as that of the bulk Pyrex glass plate. Wafers are bonded at a temperature as low as 135 °C with an applied voltage as small as 35Vdc, enabling of this technique to be applied to vacuum packaging of microelectronic devices. Experimental results reveal that an evaporated glass layer of more than 1 μ m thick is suitable for anodic bonding. Finally, The role of sodium ions in anodic bonding was also studied by investigating the theoretical bonding mechanism and examining the results of secondary ion mass spectroscopy (SIMS) analysis.
The elastic modulus and hardness of materials used in a MEMS acoustic emission sensor were determined using nanoindentation techniques. In addition to testing each individual material, the behavior of four candidate bottom electrode structures, two based on nitride layers and two based on oxide layers, have been evaluated. The multilayer nitride bottom electrode is relatively unaffected by a 950 °C annealing step; however, some evidence of second phase formation in the polycrystalline silicon layer has been observed. Increasing the thickness of the thermally grown silicon dioxide in the oxide based electrodes lowers the measured hardness of the top layer of platinum while increasing the measured modulus of the entire electrode at depths corresponding to the oxide film. Errors of up to 25% in the calculated area of indentation based on the indenter shape function occur for indentations which penetrate both the platinum and oxide films.