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Temperature resulting from the joule heating power and the turn-on and turn-off dissipation of high-power, high-frequency applications is the root cause of their thermal instability, electrical performance degradation, and even thermal-fatigue failure. Thus, the study presents thermal and electrical characterizations of the power MOSFET module packaged in SOT-227 under natural convection and forced convection through three-dimensional (3D) thermal-electric (TE) coupled field analysis. In addition, the influences of some key parameters like electric loads, ambient conditions, thermal management considerations (heat sink, heat spreader) and operation conditions (duty cycle and switching frequency) on the power loss and thermal performance of the power module are addressed. The study starts from a suitable estimation of the power losses, where the conduction losses are calculated using the temperature- and gate-voltage-dependent on-state resistance and drain current through the device, and the switching losses are predicted based on the ideal switching waveforms of the power MOSFETs applied. The effectiveness of the theoretical predictions in terms of device’s power losses and temperatures is demonstrated through comparison with the results of circuit simulation and thermal experiment.
High-quality cardiopulmonary resuscitation (CPR) is a fundamental intervention for cardiac arrest, yet health care providers rarely adhere to recommended guidelines. Real-time feedback improves CPR performance. It is currently unknown how Canadian emergency physicians assess CPR quality during cardiac arrest and if they use feedback devices. Our aim was to describe how emergency physicians assess CPR quality and to describe eventual barriers to implementation of feedback technology.
This was a cross-sectional survey that was distributed to attending and resident emergency physicians through the Canadian Association of Emergency Physicians. Responses were summarized and analyzed using descriptive statistics.
The response rate was 19% (323/1735). Visual observation was the most common method of assessing CPR quality (41.2%), with leaders standing at the foot of the bed (67.4%). This was followed by real-time pulse check (29.7%) and end-tidal CO2 values (21.7%). Only 12% of physicians utilized CPR feedback technology. The most common perceived barrier to utilization was unavailability, inexperience with devices and lack of guidelines/evidence for their use.
Most Canadian emergency physicians that responded to our survey, assess quality of CPR by standing at the foot of the bed and utilize visual observation and palpation methods which are known to be inaccurate. A minority utilize objective measurements such as ETCO2 or feedback devices, with the greatest barrier being lack of availability.
Major depressive disorder (MDD) is highly heterogeneous and can be classified as treatment-resistant depression (TRD) or antidepressant-responsive depression (non-TRD) based on patients' responses to antidepressant treatment. Methods for distinguishing between TRD and non-TRD are critical clinical concerns. Deficits of cortical inhibition (CI) have been reported to play an influential role in the pathophysiology of MDD. Whether TRD patients' CI is more impaired than that of non-TRD patients remains unclear.
Paired-pulse transcranial magnetic stimulation (ppTMS) was used to measure cortical inhibitory function including GABAA- and GABAB-receptor-related CI and cortical excitatory function including glutamate-receptor-related intracortical facilitation (ICF). We recruited 36 healthy controls (HC) and 36 patients with MDD (non-TRD, n = 16; TRD, n = 20). All participants received evaluations for depression severity and ppTMS examinations. Non-TRD patients received an additional ppTMS examination after 3 months of treatment with the SSRI escitalopram.
Patients with TRD exhibited reduced short-interval intracortical inhibition (SICI) and long-interval intracortical inhibition (LICI), as shown by abnormally higher estimates, than those with non-TRD or HC (F = 11.030, p < 0.001; F = 10.309, p < 0.001, respectively). After an adequate trial of escitalopram treatment, the LICI of non-TRD reduced significantly (t = − 3.628, p < 0.001), whereas the ICF remained lower than that of HC and showed no difference from pretreatment non-TRD.
TRD was characterized by relatively reduced CI, including both GABAA- and GABAB-receptor-mediated neurons while non-TRD preserved partial CI. In non-TRD, SSRIs may mainly modulate GABAB-receptor-related LICI. Our findings revealed distinguishable features of CI in antidepressant-resistant and responsive major depression.
The modification of halloysite nanotubes (HNTs) as fillers is very effective at improving the performance of polymers. A novel modification of HNTs through grafting dodecylamine onto their surfaces was conducted here. Owing to the improvement in dispersibility of HNTs in polytetrafluoroethylene (PTFE), the mechanical properties and wear resistance (in particular) of the dodecylamine-modified HNT-filled PTFE composite were enhanced significantly.
Information systems (IS) have facilitated workflow in the health care system for years. However, the utilization of IS in disaster medical assistance teams (DMATs) has been less studied.
In Taiwan, we started a program in 2008 to build up an information system, MEDical Assistance and Information Dashboard (MED-AID), to improve the capability and increase the efficiency of our national DMAT.
Method: The mission of our national DMAT was to provide acute trauma care and subacute outpatient care in the field after an emergency event (e.g., earthquakes). We built the IS through a user-oriented process to fit the need of the DMAT. We first analyzed the response work in the DMAT missions and reviewed the current paperwork. We evaluated the eligibility and effectiveness of the core functions of DMATs by experts in Taiwan and then developed the IS. The IS was then tested and revised each year in two table-top exercises and one regional full-scale exercise by the DMAT staffs who came from different hospitals in Taiwan.
During the past 10 years, we identified several core concepts of IS of DMAT: patient tracking, medical record, continuity of care, integration of referral resources, disease surveillance, patient information reporting, and medical resources management. The application of the IS facilitate the DMAT in providing safe patient care with continuous recording and integrate patient referral resources based on geographic information. The IS also help the planning in real-time disease surveillance and logistic function in the medical resources monitoring.
Information systems could facilitate patient care and relieve the workload on information analysis and resources management for DMATs.
Cellulitis is a common infection of the skin and soft tissue. Susceptibility to cellulitis is related to microorganism virulence, the host immunity status and environmental factors. This retrospective study from 2001 to 2013 investigated relationships between the monthly incidence rate of cellulitis and meteorological factors using data from the Taiwanese Health Insurance Dataset and the Taiwanese Central Weather Bureau. Meteorological data included temperature, hours of sunshine, relative humidity, total rainfall and total number of rainy days. In otal, 195 841 patients were diagnosed with cellulitis and the incidence rate was strongly correlated with temperature (γS = 0.84, P < 0.001), total sunshine hours (γS = 0.65, P < 0.001) and total rainfall (γS = 0.53, P < 0.001). The incidence rate of cellulitis increased by 3.47/100 000 cases for every 1° elevation in environmental temperature. Our results may assist clinicians in educating the public of the increased risk of cellulitis during warm seasons and possible predisposing environmental factors for infection.
This study addresses the causal linkage between customer incivility and service quality through the lens of self-determination theory, according to which need satisfaction as a potential mechanism mediates this relationship. Additionally, it examines the moderating role of surface acting in the relationship between customer incivility and need satisfaction. Dyadic questionnaires were collected from restaurant employees and their customers in Taiwan. A total of 190 employees and 645 customers participated in this study. Results found that need satisfaction mediates the negative relationship between customer incivility and service quality. Surface acting moderates the relationship between customer incivility and need satisfaction as well as the mediation effect of customer incivility on service quality through need satisfaction. Specifically, the indirect effect of need satisfaction on the relation between customer incivility and service quality creativity was more significantly negative at a high level of surface acting than the effect at a low level.
Research suggests an association between metabolic disorders, such as type 2 diabetes mellitus (T2DM), and schizophrenia. However, the risk of metabolic disorders in the unaffected siblings of patients with schizophrenia remains unclear.
Using the Taiwan National Health Insurance Research Database, 3135 unaffected siblings of schizophrenia probands and 12,540 age-/sex-matched control subjects were included and followed up to the end of 2011. Individuals who developed metabolic disorders during the follow-up period were identified.
The unaffected siblings of schizophrenia probands had a higher prevalence of T2DM (3.4% vs. 2.6%, p = 0.010) than the controls. Logistic regression analyses with the adjustment of demographic data revealed that the unaffected siblings of patients with schizophrenia were more likely to develop T2DM (odds ratio [OR]: 1.39, 95% confidence interval [CI]: 1.10–1.75) later in life compared with the control group. Moreover, only female siblings of schizophrenia probands had an increased risk of hypertension (OR: 1.47, 95% CI: 1.07–2.01) during the follow-up compared with the controls.
The unaffected siblings, especially sisters, of schizophrenia probands had a higher prevalence of T2DM and hypertension compared with the controls. Our study revealed a familial link between schizophrenia and T2DM in a large sample. Additional studies are required to investigate the shared pathophysiology of schizophrenia and T2DM.
Assembly optimization of printed circuit boards (PCBs) has received considerable research attention because of efforts to improve productivity. Researchers have simplified complexities associated with PCB assembly; however, they have overlooked hardware constraints, such as pick-and-place restrictions and simultaneous pickup restrictions. In this study, a hybrid group search optimizer (HGSO) was proposed. Assembly optimization of PCBs for a multihead placement machine is segmented into three problems: the (1) auto nozzle changer (ANC) assembly problem, (2) nozzle setup problem, and (3) component pick-and-place sequence problem. The proposed HGSO proportionally applies a modified group search optimizer (MGSO), random-key integer programming, and assigned number of nozzles to an ANC to solve the component picking problem and minimize the number of nozzle changes, and the place order is treated as a traveling salesman problem. Nearest neighbor search is used to generate an initial place order, which is then improved using a 2-opt method, where chaos local search and a population manager improve efficiency and population diversity to minimize total assembly time. To evaluate the performance of the proposed HGSO, real-time PCB data from a plant were examined and compared with data obtained by an onsite engineer and from other related studies. The results revealed that the proposed HGSO has the lowest total assembly time, and it can be widely employed in general multihead placement machines.
In order to improve the dispersibility of halloysite nanotubes (HNTs) in polytetrafluoroethylene (PTFE), the modification of HNT surfaces was studied with three types of modifiers (polymethyl methacrylate [PMMA], sodium dodecyl sulfate [SDS] and carboxylic acid). The modified HNTs were characterized by Fourier-transform infrared (FTIR) spectrometry, transmission electron microscopy (TEM), scanning electron microscopy (SEM) and contact angle measurements. The HNTs were used to reinforce the mechanical properties of PTFE. The mechanical results indicated that the tensile strength of the modified HNT-filled PTFE nanocomposites (F-HNT/PTFE) improved to an acceptable degree and Young's modulus increased significantly. The tribological results showed that the wear rate of F-HNT/PTFE decreased by 21–82 and 9–40 times compared to pure PTFE and the pristine F-HNT/PTFE, respectively.
Bipolar disorder is a highly heritable mental illness that transmits intergeneratively. Previous studies supported that first-degree relatives (FDRs), such as parents, offspring, and siblings, of patients with bipolar disorder, had a higher risk of bipolar disorder. However, whether FDRs of bipolar patients have an increased risk of schizophrenia, major depressive disorder (MDD), autism spectrum disorder (ASD), and attention deficit hyperactivity disorder (ADHD) remains unclear.
Among the entire population in Taiwan, 87 639 patients with bipolar disorder and 188 290 FDRs of patients with bipolar disorder were identified in our study. The relative risks (RRs) of major psychiatric disorders were assessed among FDRs of patients with bipolar disorder.
FDRs of patients with bipolar disorder were more likely to have a higher risk of major psychiatric disorders, including bipolar disorder (RR 6.12, 95% confidence interval (CI) 5.95–6.30), MDD (RR 2.89, 95% CI 2.82–2.96), schizophrenia (RR 2.64, 95% CI 2.55–2.73), ADHD (RR 2.21, 95% CI 2.13–2.30), and ASD (RR 2.10, 95% CI 1.92–2.29), than the total population did. These increased risks for major psychiatric disorders were consistent across different familial kinships, such as parents, offspring, siblings, and twins. A dose-dependent relationship was also found between risk of each major psychiatric disorder and numbers of bipolar patients.
Our study was the first study to support the familial coaggregation of bipolar disorder with other major psychiatric disorders, including schizophrenia, MDD, ADHD, and ASD, in a Taiwanese (non-Caucasian) population. Given the elevated risks of major psychiatric disorders, the public health government should pay more attention to the mental health of FDRs of patients with bipolar disorder.
Findings from observational studies on the associations between vitamin E intake and stroke risk remain controversial, and the dose–response relationship between vitamin E intake and risk of stroke remains to be determined. We conducted a meta-analysis of prospective studies aiming to clarify the relationships between vitamin E intake and risk of stroke. Relevant studies were identified by searching online databases through to June 2018. We computed summary relative risks (RR) with corresponding 95 % CI. Among 3156 articles retrieved from online databases and relevant bibliographies, nine studies involving 3284 events and 220 371 participants were included in the final analyses. High dietary vitamin E intake was inversely associated with the risk of overall stroke (RR=0·83, 95 % CI 0·73, 0·94), and with the risk of stroke for individuals who were followed-up for <10 (RR=0·84, 95 % CI 0·72, 0·91). There was a non-linear association between dietary vitamin E intake and stroke risk (P=0·0249). Omission of any single study did not alter the summary result. In conclusion, this meta-analysis suggests that there is a significant inverse relationship between dietary vitamin E intake and stroke risk. This meta-analysis provides evidence that a higher dietary vitamin E intake is associated with a lower stroke risk.
Real-time Precise Point Positioning (PPP) has been evolved as a cost-effective technique for highly precise maritime positioning. For a long period, maritime PPP technology has mainly relied on the Global Positioning System (GPS). With the revitalisation of GLONASS and the emerging BeiDou navigation satellite system (BDS), it is now feasible to investigate real-time navigation performance of multi-constellation maritime PPP with GPS, BDS and GLONASS. In this contribution, we focus on maritime PPP performance using real world maritime kinematic data and real-time satellite correction products. The results show that BDS has lower position accuracy and slower convergence time than GPS. The BDS and GPS combination has the best performance among the dual-constellation configurations. Meanwhile, the integration of BDS, GLONASS and GPS significantly improves the position accuracy and the convergence time. Some outliers in the single constellation configuration can be mitigated when multi-constellation observations are utilised.
A high power laser system was used to drive the ignition of inertial confinement fusion (ICF), of which the high energy, the uniform focal spot, the accurate laser waveform, and the synchronization between the laser beams are key parameters. To accomplish this, global laser characteristics control should be assured, which was the main purpose of the injection laser system. In this paper, the key technological progress involved in the improvement of the performance of the injection laser of SG-II is reported, including frequency domain control, time domain control, near-field spatial shaping, pre-amplifier technology, and the optical parametric chirped pulse amplification pump source.
We present a recent progress of the SG-II 5PW facility, which designed a multi-petawatt ultrashort pulse laser based on optical parametric chirped-pulse amplification (OPCPA). The prior two optical parametric amplifiers have been accomplished and chirped pulses with an energy of 49.7 J and a full-width-at-half-maximum (FWHM) spectrum bandwidth of 85 nm have been achieved. In the PW-scale optical parametric amplification (OPA), with the pump pulse that has an energy of 118 J from the second harmonic generation of the SG-II 7th beam, the pump-to-signal conversion efficiency is up to 41.9%, which to the best of our knowledge is the highest among all of the reported values for OPCPA systems. The compressed pulse is higher than 37 J in 21 fs (1.76 PW), and the focal spot is
after the closed-loop corrections by the adaptive optics. Limited by the repetition of the pump laser, the SG-II 5PW facility operates one shot per hour. It has successfully been employed for high energy physics experiments.
An optically addressed liquid crystal modulator for wavefront control of 1053 nm laser beam is reported in this paper. Its working principle, control method and spatial phase modulation capability are mainly introduced. A new method of measuring the relationship between gray level and phase retardation is proposed. The rationality of the curve is further confirmed by designing special experiments. According to the curve, several spatial phase distributions have been realized by this home-made device. The results show that, not only the maximum phase retardation is larger than
for 1053 nm wavelength, but also the control accuracy is high. Compared with the liquid crystal on silicon type spatial light modulator, this kind of modulator has the advantages of generating smooth phase distribution and avoiding the black-matrix effect.