Testing In Field Research Articles

Assessment of workplace bullying in Italy by INAIL: forensic and occupational medicine considerations.

The Authors, after a broad examination of the operating methods of inail (National Institute for Accident Insurance at Work) for the correct assessment and indentification of workplace bullying, carried out a comparative evaluation on the various diagnostic tests in the forensic psychiatric field for this occupational problem.

Polymer‐Based MEMS Sensor for Label‐Free Chikungunya Virus Detection

AbstractPiezoelectric MEMS (Micro‐Electro‐Mechanical Systems) Cantilevers have successfully been used in a wide variety of applications in recent years. This paper is a simulation‐based study on Micro‐cantilever based Piezoelectric MEMS biosensors for Chikungunya Virus (CHIKV) detection. In addition to providing early detection, the proposed method is label‐free, faster, and more reliable. The proposed biosensor detects CHIKV E2 protein via MEMS Sensor. The basic principle involves using piezoelectric material on a micro‐cantilever for biomaterial detection. A piezoelectric MEMS cantilever is simulated in COMSOL Multiphysics and compared for voltage, stress, and displacement for three materials (silicon, gold, and PDMS). Analytical equations are derived. Post‐processing for biosensor design is done in SIMULINK. Simulated voltage, stress, and displacement show a linear relationship with the viral load. PDMS also provided the highest voltage and displacement among the three materials used for MEMS simulation. The graphs show the comparison between simulated and analytical values. Simulation results are also compared to clinical results to prove the biosensor's validity. MEMS Biosensor performance matches with the RT‐PCR results, with the added advantage of faster results. Diagnostic tests in the medical field can be performed using the proposed biosensor.

Experimental and numerical study of reverse power generation in coastal axial flow pump system using coastal water

Coastal areas require frequent drainage to prevent waterlogging, and are often equipped with axial flow pump systems to enable this. Reverse power generation from CAPS (coastal axial flow pump systems) using coastal water is an untapped but high-potential source of renewable energy. However, the design of CAPS usually considers only the pumping conditions; there isa huge difference in flow during the reverse power generation condition (TC) and the conventional pumping condition (PC). If such a CAPS were to operate under TC, there would be unknown risks to its hydraulic performance and operational stability. In this study a special experimental test bench is built for the evaluation of CAPS. Energy test and measurement of internal pressure field are carried out for TC and PC of CAPS under full flow condition. Then, the energy loss characteristics and the propagation law of CAPS under PC and TC are investigated by an unsteady numerical simulation, and the results of the simulation are compared with the experimental results. The flow field difference between the PC and TC is analyzed in detail, and the hydraulic performance, operation safety, and stability of CAPS under TC are evaluated. This paper is expected to be of reference value for the renewable utilization of low-head water resources in coastal areas.

An Anisotropic Dielectric Elastomer Actuator with an Oriented Electrospun Nanofiber Composite Film

AbstractAnisotropic actuation, a universal phenomenon in nature, may be inspiring for the development of intelligent soft robotics in the future. For dielectric elastomers (DEs), important investigations have been done to decrease the voltage and increase the actuation strain. However, mechanical isotropy of synthetic DEs shows in‐plane uniform deformation, lacking the controllability of the actuation direction. Herein, an anisotropic DE (denoted as ADE) is constructed by casting Ecoflex/BaTiO3 solution onto oriented TPU nanofibrous membranes fabricated via drum electrospinning. The resulting ADE with a seamless three‐layer structure features mechanical anisotropy in the elastic modulus, with the maximum ratio between x and y directions of the plane being 11. A prototype ADE‐based actuator demonstrates a high electroactuation anisotropy of 3.95, a large unidirectional length strain of 15%, and a high energy density of 0.014 MJ m−3 at an electric field of 40 V µm−1. Two potential applications, a flow divider valve simulating the Transwell test in the medical field and a mechanical stimulus component mimicking the maturation of cardiomyocytes, are successfully demonstrated. Thus, this work offers a versatile yet simple approach for fabricating anisotropic electroactive elastomer actuators in the future.

Multi-scale modelling of evolving plastic anisotropy during Al-alloy sheet forming

Accurate modelling of local evolving texture and yield surface evolution in complex strain path are of crucial importance to the accurate sheet metal forming simulations. This work proposed a novel multi-scale computational scheme, in which the full-field crystal plasticity (CP) modelling is mapped and real-time updated into each integration point following the local strain path in the finite element (FE) model. By the real-time close-loop feedback and update between the FE model and CP model, the evolving texture and its induced anisotropic plasticity evolution are considered utilizing on-the-fly virtual tests in the full deformation field. To carefully verify the developed computational framework, a comprehensive validation including plastic anisotropy characterization, cyclic hardening tests and deep drawing tests is conducted in an AA6016-T4 aluminium sheet with strong cube texture using ESAFORM Benchmark 2021. By comparison with experimental results and the conventional approaches with constant yield surface for the forming case, the newly developed method is thoroughly validated, showing that the significant texture evolution is observed in large plastic deformation and various strain paths lead to different texture evolution. The local evolving texture induced plastic anisotropy evolution has a considerable effect on the prediction accuracy of the deep drawing simulations, such as earing profile, wall thickness and loading history. Additionally, this method does not increase too much computation cost, enabling cost-effectively simulation of complex forming processes.

Field-Scale Modeling of Interwell Tracer Flow Behavior to Characterize Complex Fracture Networks Based on the Embedded Discrete Fracture Model in a Naturally Fractured Reservoir

Summary In a naturally fractured reservoir, natural fractures can not only provide main paths for fluid flow and increase its permeability but also complicate flow behavior and production performance. Interwell tracer tests have been widely applied to estimate the petrophysical properties; however, limited attempts have been made to accurately identify the natural fracture networks. In this study, the newly proposed numerical models have been verified and used to characterize the fracture distributions in a naturally fractured reservoir conditioned to tracer transport behavior. The stochastic fracture modeling approach is implemented to generate the randomly distributed natural fractures which are dealt with the embedded discrete fracture model (EDFM) while ensuring its sufficient accuracy. To be specific, the matrix domain is discretized using the structured grids, within which each embedded fracture is divided into a series of segments. Subsequently, nonneighboring connections (NNCs) allow us to couple the flow of fluid and tracer between the nonneighboring grid cells, while the historical tracer profiles are matched to delineate the geometry and properties of the fractures by taking multiple tracer transport mechanisms into account. Furthermore, the influences of fracture number, fracture length, fracture orientation, and tracer dispersion on the tracer production concentration have been investigated through sensitivity analysis. The response of an interwell tracer model is sensitive to the fracture parameters rather than tracer properties. A fracture network with its orientation parallel to the mainstream direction will cause the earliest tracer breakthrough. The tracer breakthrough time with an average fracture length of 40 m is 110 days earlier than that with a mean fracture length value of 10 m, while the tracer production peak concentration for the former is nearly two times higher than for the latter. A larger fracture number results in an earlier tracer breakthrough, and an intermediate fracture number will lead to the highest tracer production concentration. Additionally, the newly developed model has been validated through its comparison with the commercial ECLIPSE simulator and then extended to field applications to identify the possible fracture distributions by simulating multiwell tracer tests in the Midale field. The flexible and pragmatic EDFM-based method developed in this study can model the interwell tracer flow behavior as well as characterize the properties and geometries of the natural fractures with better accuracy and calculation efficiency in comparison with other fracture simulation methods (e.g., local grid refinement method).

The Trade-Off Between Luminance and Color Contrast Assessed With Pupil Responses.

A scene consisting of a white stimulus on a black background incorporates strong luminance contrast. When both stimulus and background receive different colors, luminance contrast decreases but color contrast increases. Here, we sought to characterize the pattern of stimulus salience across varying trade-offs of color and luminance contrasts by using the pupil light response. Three experiments were conducted with 17, 16, and 17 healthy adults. For all experiments, a flickering stimulus (2Hz; alternating color to black) was presented superimposed on a background with a complementary color to the stimulus (i.e., opponency colors in human color perception: blue and yellow for Experiment 1, red and green for Experiment 2, and equiluminant red and green for Experiment 3). Background luminance varied between 0% and 45% to trade off luminance and color contrast with the stimulus. By comparing the locus of the optimal trade-off between color and luminance across different color axes, we explored the generality of the trade-off. The strongest pupil responses were found when a substantial amount of color contrast was present (at the expense of luminance contrast). Pupil response amplitudes increased by 15% to 30% after the addition of color contrast. An optimal pupillary responsiveness was reached at a background luminance setting of 20% to 35% color contrast across several color axes. These findings suggest that a substantial component of pupil light responses incorporates color processing. More sensitive pupil responses and more salient stimulus designs can be achieved by adding subtle levels of color contrast between stimulus and background. More robust pupil responses will enhance tests of the visual field with pupil perimetry.

Operation and Testing of Indirect Field Oriented Control of Asymmetrical Six-Phase Open-Ended Winding Induction Machine Using Hardware-in-Loop (HIL) Emulator

This study deals with an asymmetrical six-phase open-ended winding induction machine in closed loop operation using indirect field-oriented control scheme. The closed loop scheme has been developed by using the two axis (d-q) modeling of six-phase induction machine in rotating synchronous reference frame and can be easily extended to any multiphase machine having the stator winding which are the multiple of three. Operation under steady-state is considered to develop the phasor diagram in closed loop operation of machine in the motoring mode. The performance of the asymmetrical six-phase induction machine (opened ended winding) is investigated in the entire four-quadrant operation. The complete machine drive system was developed by using MATLAB/Simulink, which was used to obtain analytical results in different modes. Furthermore, the analytical results in the motoring mode were experimentally validated through real-time simulation by using Typhoon hardware-in-loop (HIL) emulator.

Suitability of determining percentage hearing loss for monitoring cochlear implant rehabilitation

Calculation of percentage hearing loss (pHV) from the pure-tune audiogram according to Röser in 1973 or from the speech audiogram according to Boenninghaus and Röser in 1973 is a method still applied for quantitative assessment of hearing. However, this is not common for the evaluation of postoperative results of implantable hearing systems. During the regular work-up after cochlear implantation (CI) in Germany, all necessary parameters are available for calculation of pHV either from categorical loudness scaling (pHVKLS) or speech-recognition threshold (pHVFB). The parameters pHVKLS and pHVFB are introduced and calculated from data available from clinical routine. Their potential applicability for assessment of the result of CI is evaluated. This study comprises retrospective chart review of audiological parameters from 66CI procedures in one tertiary referral center. pHVKLS was calculated from the equal loudness curve 5CU, pHVFB from the Freiburg speech test in free field. While pHVKLS shows small variation, the variation in pHVFB is initially larger but decreases over time. Furthermore, starting from initial fitting, the mean pHV shows convergence over time. The difference between pHVFB and pHVKLS is positive and statistically significant. It is possible to calculate pHVKLS and pHVFB from routine data. Acorrelation of the difference between pHVFB and pHVKLS with successful CI performance seems plausible.

The heat conductivity mechanism of the IR heating propagation for surfaces decontamination in protected ground

Modern greenhouses usually have flat concrete surfaces with communications for subsurface and above surface heating. It is proposed to disinfect surfaces with infrared radiation. We solve the corresponding heat equation. Field tests of the temperature field in protected ground have been performed to verify the mathematical model validity and to determine the empiric coefficients. The numerical investigation of the solution when the quantity of the Fourier series terms changes from 100 to 200 gives the heating time τ = 15 …16 min. Using these theoretical and experimental investigations one may conclude that the sufficient heating of a surface at the depth up to 5 cm needs a relatively long time of 15 …16 min and the surface will be strongly overheated during this time. We recommend using infrared heating for the decontamination purposes, but only in the case of thin layers of the ground or of the surface. The temperature necessary for the surface contamination and elimination of different pathogenic microorganisms, fungi, rots etc. emerging in the protected ground is achieved at a relatively small-time interval of 30…40 c. We think that the infrared radiation is a powerful and advanced method of sanitation of thin layers and surfaces.

Forensic Genetics as a Tool for Forensic Investigation at the Crime Scene

The 21st century will bring us, as the 20th century brought us the specialization of forensic medicine, an increasing integration of subspecialties. The importance of DNA testing in the forensic field as a method of identification lies in its potential applicability to solve many cases that would be difficult to clarify by conventional investigative procedures and in the very high reliability of its results, only comparable with dactyloscopic expertise. The application of this profile allows the use of any fluid from the same person since it presents the same genetic code regardless of where the print comes from such as blood, saliva, semen, hair, sweat. The present research consists of a descriptive investigation that started with a transversal observational study of the application of DNA expertise for identification purposes. A bibliographic review of specialized sources on the subject was carried out, and an assessment was made of the importance of the application of DNA expertise as evidence in criminal proceedings and its impact on due process. It was analyzed the vulnerabilities that threaten the quality of the expertise and how the evaluation of the evidence can be thundered doubtful or inconclusive if the established protocols are not fulfilled, in addition the importance and perspectives of the genetic bank for forensic purposes were widely discussed, as well as the care to be taken by the risks that this has if the security measures provided for this purpose are not met.

Expanding the circularity of plastic and biochar materials by developing alternative low environmental footprint sensors

Flexible screen-printing technology modified with nano/material coating boosted the manufacturing of highly sensitive electrochemical sensors for fast and easy-to-handle tests in different application fields.

The Critical Need to Re-Balance Theory Building and Testing in the IS Field

The Critical Need to Re-Balance Theory Building and Testing in the IS Field

Incidence and Pattern of Neuro-Ophthalmological Disorders Presenting to Vitreoretinal Clinics in Bhutan: A 3-Year National Study.

To inform national health policy, we quantified the pattern of neuro-ophthalmological disorders (NODs) presenting to the national vitreoretinal clinics in Bhutan. Retrospective cross-sectional study. We reviewed all new NODs patients over three years. Demographic data, presenting complaints, treatment history, systemic diseases, diagnostic procedures, and diagnoses were quantified. Logistic regression examined the odds of factors linked to more common NODs. Of 226 patients, the majority were males (54.0%), farmers (60.2%), and urbanites (55.8%). Loss of vision was the most common presenting complaint (57.9%), followed by head or orbital trauma (19.5%). The best corrected visual acuity (BCVA) of 216 eyes (47.8%) was ≤6/60. Hypertension was the most common systemic disease (16.4%), followed by diabetes (3.5%), and intracranial space-occupying lesions (3.5%). Neuroimaging (37.6%) was the most common diagnostic test performed, followed by visual field testings (VFTs) (22.9%). With a NOD incidence of 7.8% p.a. (226/2913), optic atrophy (OA) was diagnosed in 134 patients (59.3%). Other common NODs were optic neuritis (15.5%), papilloedema (9.3%), and traumatic optic neuropathy (8.4%). Female gender increased the odds for glaucomatous OA by 2.65× (p = 0.044), and age by 1.09× per year (p < 0.001). Being female increased the odds of optic neuritis by 2.57× (p = 0.03). Over half of the NODs were OA, which could be curable with timely treatment. Improved treatment of glaucoma and non-communicable diseases would reduce the risk of NODs-induced visual loss in Bhutan. The need for improved neuro-ophthalmological assessment and a coordinated multidisciplinary approach to NODs are the highest priorities.

Design of Radiation Resistant Pre-amplifier for fusion reactors

The research of controlled nuclear fusion is not a simple process. The upcoming accomplishment of ITER means the beginning of a new phase of controlled nuclear fusion, which is building a fusion reactor. The operating electronics related to fusion reactors need to adapt to harsh environment and minimize the risk of any possible irradiation. Pre-amplifiers are widely used for signal conditioning in various diagnostic systems. And if not shielded, they would be easily damaged in a environment with strong radiation. In this study, a kind of Radiation Resistant Pre-amplifier (RRP) has been designed and manufactured. To verify its performance under radiation, tests in both gamma and neutron fields were carried out. And the performance of RRP is compared with that of an Ordinary Pre-amplifier (OP). The RRP was irradiated with gammas from a Co-60 source up to an accumulated dose of 1MGy, and was also irradiated with neutrons under a tandem accelerator up to a total neutron flux of 1013 n/cm2. The test results prove a performance improvement of radiation hardness on the RRP. And shielding optimization has been discussed with the circumstances of ITER port cell area in this paper. The RRP could better adapt to the complex irradiation environment of fusion reactors and possibly reduce shielding in the future.

Shaking table test and numerical simulation of free field in sand-sawdust mixed soil

The sand-sawdust mixture has been frequently used in the shaking table test because it is easy to adjust the shear wave velocity of model soil by changing the sawdust content. In this paper, the dynamic properties and the seismic responses of the free field in sand-sawdust mixture as well as the boundary effects of the laminar shear model box were investigated using a series of shaking table tests. The influences of different constitutive models on to the seismic response analysis of the model soil were studied by comparing the numerical results with the experimental results. The comparison shows that the boundary effect mainly influences the model soil within 0.75 times of the soil depth from the box boundary and the impact decreases with the increasing of soil depth. The natural frequency and acceleration amplification factor of the field decrease with the increasing amplitude of the ground motion. The comparison of the seismic response results for different constitutive models of the Hardin-Drnevich, Ramberg-Osgood, and Davidenkov models using the one-dimensional equivalent linearization method indicated that the combination of Davidenkov and Hardin-Drnevich model could improve the accuracy of seismic response for sand-sawdust mixed soil.

A novel strain field reconstruction method for test monitoring

For the static loading test in the aerospace field, conventional strain field reconstruction based on finite element analysis (FE-SFRM) is difficult to meet the accuracy requirements of test monitoring. A novel experiment strain field reconstruction method (EXP-SFRM) is proposed to improve the accuracy and monitoring effect of reconstructed field. Firstly, the coordinates of strain gauges are introduced to build the connections in space between discrete strain gauges and make it possible to check the accuracy of finite element analysis. Next, the real-time strains with high-precision coordinates are employed to reconstruct the strain field by radial basis function. A cantilever plate test and a large opening cylindrical shell (LOCS) test are performed to validate the high accuracy and good monitoring effect of EXP-SFRM. For the LOCS test, a maximum inward and outward bending criterion (MIOBC) is also proposed to determine the buckling regions. The results show that the average errors of EXP-SFRM are 2.8% (cantilever plate) and 17.4% (LOCS), which are 4.8% and 26.4% lower than these of FE-SFRM. Additionally, for LOCS, the risk regions predicted by EXP-SFRM are finally consistent with the real buckling regions, while these predicted by FE-SFRM are not. Compared with conventional FE-SFRM, the EXP-SFRM is proved to have high accuracy and good monitoring effect during test process.

Probe-AUT Multiple Reflection Suppression in the Over the Air Measurement of 5G Antennas Using Matrix Pencil Method

The effect of probe proximity to the antenna under test (AUT) in the fixed-probe spherical near field (SNF) measurement system is investigated. The matrix pencil method (MPM) is utilized to suppress the undesired multiple reflections between AUT and probe, and the optimal angular region for correction is determined in this scenario. The simulation results are compared with a reference set of data in terms of transmission coefficients and radiation patterns to evaluate the performance of the MPM in the probe-generated echo filtering procedure. To verify the functionality of the MPM in practice, two antennas are exploited as different probes to implement a spherical measurement system in a mini-anechoic chamber, which is developed for conducting the over the air (OTA) measurements of the fifth-generation (5G) antennas. By comparing the radiation pattern results, it is observed that applying the MPM to the sampled data leads to more accurate results in a compact near field (NF) measurement setup.

New technology can benefit established middle ear implant users: Samba 2 vs previous models of audio processors for Vibrant Soundbridge

IntroductionThe Vibrant Soundbridge (VSB) is a semi-implantable hearing aid for patients with various types of hearing loss and has been available for over 25 years. Recently, new audio processors with advanced signal processing, noise reduction, and multi-microphone technology have appeared. The aim of this study is to compare the benefits of using the newest Samba 2 processor to the previous generation processors in a group of experienced VSB users.MethodsThere were 22 experienced VSB users (mean time of using VSB was 9 years, SD = 2) who had their processor (D404 or Amadé) upgraded to the newest model (Samba 2). The mean age of the subjects was 56 years (SD = 20). Assessments were made by free-field audiometry, speech reception in quiet and noise, and Patient-Reported Outcome Measures (PROMs).ResultsHearing tests in free field showed statistically significant improvements in hearing sensitivity and speech discrimination in quiet and noise with the Samba 2 audio processor compared to the earlier technology. PROMs confirmed the benefits of using the newest audio processor and there was more satisfaction in terms of usability.ConclusionsAccess to modern technology for VSB patients provides measurable benefits.

"K-Powder" Exposure during Adolescence Elicits Psychiatric Disturbances Associated with Oxidative Stress in Female Rats.

Ketamine, also called 'K-powder' by abusers, an analog of phencyclidine, primarily acts as an antagonist of N-methyl-D-aspartic acid (NMDA) receptors, therapeutically used as an anesthetic agent. Ketamine also stimulates the limbic system, inducing hallucinations and dissociative effects. At sub-anesthetic doses, ketamine also displays hallucinatory and dissociative properties, but not loss of consciousness. These behavioral consequences have elicited its recreational use worldwide, mainly at rave parties. Ketamine is generally a drug of choice among teenagers and young adults; however, the harmful consequences of its recreational use on adolescent central nervous systems are poorly explored. Thus, the aim of the present study was to characterize the behavioral and biochemical consequences induced by one binge-like cycle of ketamine during the early withdrawal period in adolescent female rats. Adolescent female Wistar rats (n = 20) received intraperitoneally administered ketamine (10 mg/kg/day) for 3 consecutive days. Twenty-four hours after the last administration of ketamine, animals were submitted to behavioral tests in an open field, elevated plus-maze, and forced swimming test. Then, animals were intranasally anesthetized with 2% isoflurane and euthanized to collect prefrontal cortex and hippocampus to assess lipid peroxidation, antioxidant capacity against peroxyl radicals, reactive oxygen species, reduced glutathione, and brain-derived neurotrophic factor (BDNF) levels. Our results found that 24 h after recreational ketamine use, emotional behavior disabilities, such as anxiety- and depression-like profiles, were detected. In addition, spontaneous ambulation was reduced. These negative behavioral phenotypes were associated with evidence of oxidative stress on the prefrontal cortex and hippocampus.