Metal silicide/poly-Si Schottky diodes for uncooled microbolometers

Nickel silicide Schottky diodes formed on polycrystalline Si films are proposed as temperature sensors of monolithic uncooled microbolometer IR focal plane arrays. Structure and composition of nickel silicide/polycrystalline silicon films synthesized in a low-temperature process are examined by means of transmission electron microscopy. The Ni silicide is identified as multi-phase compound composed by 20 to 40% of Ni3Si, 30 to 60% of Ni2Si and 10 to 30% of NiSi with probable minor content of NiSi2 at the silicide/poly-Si interface. Rectification ratios of the Schottky diodes vary from ~100 to ~20 for the temperature increasing from 22 to 70C; they exceed 1000 at 80K. A barrier of ~0.95 eV is found to control the photovoltage spectra at room temperature. A set of barriers is observed in photo-emf spectra at 80K and attributed to the Ni-silicide/poly-Si interface. Absolute values of temperature coefficients of voltage and current are found to vary from 0.3 to 0.6%/K for forward biasing and around 2.5%/K for reverse biasing of the diodes.Comment: 18 pages, 7 figure

Quantifying prosthetic and intact limb use in upper limb amputees via egocentric video: an unsupervised, at-home study

Analysis of the manipulation strategies employed by upper-limb prosthetic device users can provide valuable insights into the shortcomings of current prosthetic technology or therapeutic interventions. Typically, this problem has been approached with survey or lab-based studies, whose prehensile-grasp-focused results do not necessarily give accurate representations of daily activity. In this work, we capture prosthesis-user behavior in the unstructured and familiar environments of the participants own homes. Compact head-mounted video cameras recorded ego-centric views of the hands during self-selected household chores. Over 60 hours of video was recorded from 8 persons with unilateral amputation or limb difference (6 transradial, 1 transhumeral, 1 shoulder). Of this, almost 16 hours of video data was analyzed by human experts using the 22-category ‘TULIP’ custom manipulation taxonomy, producing the type and duration of over 27,000 prehensile and non-prehensile manipulation tags on both upper limbs, permitting a level of objective analysis not previously possible with this population. Our analysis included unique observations on non-prehensile manipulations occurrence, determining that 79% of transradial body-powered device manipulations were non-prehensile, compared to 60% for transradial myoelectric devices. Conversely, only 16-19% of intact limb activity was non-prehensile. Additionally, multi-grasp terminal devices did not lead to increased activity compared to 1DOF devices

High-frequency Heating of Wood with Moisture Content Gradient

The influence of moisture content (MC) gradient on the development of a temperature gradient in wood heated in a high-frequency (HF) electromagnetic field was investigated. Fifteen layers of 1.6-mm-thick beech veneer (Fagus sylvatica L.), with dimension 400 X 400 mm, were used to simulate a moisture content (MC) gradient. A uniform MC of 5, 10, 15, and 20%, and two MC gradient schemes ranging from 20% to 5%, were used in the experiment. The dielectric constant and loss tangent were measured before HF heating at 6.3 MHz. During HF heating of wood, the magnitude of the MC, the shape of the MC gradient, and the potential for thermal losses influence the development of the temperature gradient. An MC gradient in a laminated composite could be used to control the shape and severity of the temperature gradient during HF heating

Patient Perspectives on Osseointegration: A National Survey of Veterans with Upper Limb Amputation

INTRODUCTION: Osseointegrated (OI) prostheses have a unique benefit-risk profile among prosthetic alternatives and have been marketed in the United States under a Humanitarian Device Exemption since 2015. Information about upper limb prosthesis user perspectives on benefits and risks, prosthesis-user subpopulations for whom OI is most acceptable, and outcomes that matter most to patients could help inform clinical and regulatory decision-making. Recent 21st Century Cures legislation expanded the role of patient experience data in the decision-making process of the U.S. Food and Drug Administration, recognizing that patient perspectives may be informative to regulators. OBJECTIVE: To better understand prosthesis user perspectives about the benefits and risks associated with upper limb OI prostheses. DESIGN: Patient perspective survey. SETTING: Telephone administration. PARTICIPANTS: National sample of veterans with upper limb loss. INTERVENTIONS: NA MAIN OUTCOME MEASURES: Benefit-risk survey developed for this study. RESULTS: Twenty-eight percent of unilateral and 13% of bilateral amputees were willing to consider osseointegration surgery. Multivariate logistic regression models [OR; 95% CI] showed that transhumeral amputation level [OR 1.40; 1.01-1.98] was associated with greater willingness to consider surgery, whereas older age [OR 0.17; 0.09-0.32] and higher VR-12 Mental Component Summary [OR 0.53; 0.35-0.81] were associated with less willingness. Having a durable/reliable device, the ability to do more activities, and having a comfortable device were rated as very important or somewhat important by 98% or more for every risk condition. CONCLUSIONS: Persons who were older, had transradial amputation (compared to transhumeral), and those who had better mental functioning were less willing to consider this surgery. Respondents who were willing to consider surgery indicated that the most important potential benefits were obtaining a durable/reliable device, the ability to do more activities, and having a comfortable device. Most were willing to accept one or more risks of surgery, with long-term risks including chronic pain, loss of nerve function, or device failure considered the most unacceptable. LEVEL OF EVIDENCE: III. has been contributed to by US Government employees and their work is in the public domain in the USA

Study of some citrus flavanones against zearalenone accumulation by Fusarium graminearum

Zearalenone (ZEA) is produced by Fusarium fungi in grains, in particular by Fusarium graminearum. ZEA is a non-steroidal estrogenic mycotoxin widely distributed. The flavanones naringin (NAR), hesperidin (HES) and neohesperidin (NEO) were extracted from citrus industry wastes, such as immature fruits, and tested against ZEA accumulation by F. graminearumin rice. Response Surace Methodology (RSM) was applied in order to optimize flavanones concentrations to achieve total ZEA reduction. Using this methodology, the optimal combinations obtained were HES -NAR: 0.232-0.299, HES-NEO: 0.400-0.001 and NAR-NEO: 0.423-0.001 mmol/kg rice in dry basis. However, NEO seems to have no effect on ZEA inhibition. When it is mixed with other flavanones, they need to be used in higher concentrations than when used alone. These theoretical concentrations obtained by RSM were assayed to verify the results, achieving total inhibition of ZEA accumulation in rice media. The use of the studied flavanones, obtained inexpensively from the residues of citrus industry, would tend to reduce food waste, improve profitability of these industries and diminish ZEA occurrence in rice.Fil: Pok, Paula Sol. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Orgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Salas, María Paula. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Orgánica; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; ArgentinaFil: Resnik, Silvia Liliana. Fundación de Investigaciones Científicas "Teresa Benedicta de la Cruz"; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Orgánica; ArgentinaFil: Pacin, A.. Fundación de Investigaciones Científicas "Teresa Benedicta de la Cruz"; ArgentinaFil: Munitz, Martín. Universidad Nacional de Entre Ríos; Argentin

Unbroken supersymmetry in the Aharonov-Casher effect

We consider the problem of the bound states of a spin 1/2 chargless particle in a given Aharonov-Casher configuration. To this end we recast the description of the system in a supersymmetric form. Then the basic physical requirements for unbroken supersymmetry are established. We comment on the possibility of neutron confinement in this system

Structural validity and reliability of the patient experience measure: A new approach to assessing psychosocial experience of upper limb prosthesis users

Recent advances in upper limb prosthetics include sensory restoration techniques and osseointegration technology that introduce additional risks, higher costs, and longer periods of rehabilitation. To inform regulatory and clinical decision making, validated patient reported outcome measures are required to understand the relative benefits of these interventions. The Patient Experience Measure (PEM) was developed to quantify psychosocial outcomes for research studies on sensory-enabled upper limb prostheses. While the PEM was responsive to changes in prosthesis experience in prior studies, its psychometric properties had not been assessed. Here, the PEM was examined for structural validity and reliability across a large sample of people with upper limb loss (n = 677). The PEM was modified and tested in three phases: initial refinement and cognitive testing, pilot testing, and field testing. Exploratory factor analysis (EFA) was used to discover the underlying factor structure of the PEM items and confirmatory factor analysis (CFA) verified the structure. Rasch partial credit modeling evaluated monotonicity, fit, and magnitude of differential item functioning by age, sex, and prosthesis use for all scales. EFA resulted in a seven-factor solution that was reduced to the following six scales after CFA: social interaction, self-efficacy, embodiment, intuitiveness, wellbeing, and self-consciousness. After removal of two items during Rasch analyses, the overall model fit was acceptable (CFI = 0.973, TLI = 0.979, RMSEA = 0.038). The social interaction, self-efficacy and embodiment scales had strong person reliability (0.81, 0.80 and 0.77), Cronbach\u27s alpha (0.90, 0.80 and 0.71), and intraclass correlation coefficients (0.82, 0.85 and 0.74), respectively. The large sample size and use of contemporary measurement methods enabled identification of unidimensional constructs, differential item functioning by participant characteristics, and the rank ordering of the difficulty of each item in the scales. The PEM enables quantification of critical psychosocial impacts of advanced prosthetic technologies and provides a rigorous foundation for future studies of clinical and prosthetic interventions