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This article presents a modified asymmetrical half-bridge flyback converter (AHBFC) to fulfill the single-stage step-down ac-dc universal input voltage application. This topology is obtained from the integration of a buck-type power factor correction, an auxiliary energy buffer, and a conventional AHBFC. By sharing common switches and utilizing transformer's leakage inductor, the single-stage circuit can achieve both high power factor (PF) and low total harmonic distortion with the simple constant on-time control while regulating the dc output voltage. In addition, it is able to operate in universal input voltage with low dc link voltage and low output voltage. Moreover, the zero voltage switching and the zero current switching features of the power switches can also be achieved. Detailed analyses and design procedures of the proposed converter are given and verified by the experimental results. Finally, the comparison with reported circuit topologies and power loss analyses verified by experimental results are presented to provide the insight of practical design.

The continuous technological advancement of computer simulation, display technology, and the internet of things leads to the opportunities to use cross-reality (XR) technologies in crisis management. XR emphasizes the compositions of different concepts in reality-virtuality continuum under a shared online virtual world, including virtual reality (VR), augmented reality (AR), and mixed reality (MR). It is touted as a promising tool to facilitate crisis management strategies in different stages, including prevention, onsite management, and recovery. This research contributes to the field of research in VR, XR, and crisis management (an essential component of healthcare) in the following four ways: (1) It proposes an idea to apply XR in crisis management. (2) It proposes a framework to connect VR, AR, and MR serving one purpose. (3) It presents a qualitative study to examine the user perception of the XR-based crisis management method. (4) It brings out the challenges and opportunities of using XR in crisis management.

COVID-19 should not be the world's last public health disaster, so there is an urgent need to learn from COVID-19 to prepare better for the next public health disaster. This study aims to understand the factors that make people wear a face mask at the beginning of an outbreak of public health disaster. Semi-structured interviews were conducted during April 2020 in China, one month after the COVID-19 was declared a pandemic. The respondents were members of the public living in China, covering two age groups: young adults and older adults. They were recruited using a convenient sample and snowball sampling strategy. The results were analysed using content analysis. Seventeen subjects were recruited, among which nine were young adults (average age = 26.4; SD = 10.5), and eight were older adults (average age = 60.4; SD = 12.1). This study found that environmental factors, personal factors, factors concerning wearing masks, specific circumstances, and development of the pandemic were the common factors considered by both young adults and older adults. This study should help the authority formulate prevention policies better to reduce the risk of an outbreak if there is a new virus outbreak in the future, unfortunately., Graphical abstract Image 1

Vietnam is in the emerging stage in supporting and protecting people with disabilities (PWDs) in terms of employment rights and opportunities. The main purpose of this study was to explore how Vietnamese perceive their coworkers with disabilities in general workplace settings. In addition, the secondary objective of this study was to explore how Vietnamese perceive community acceptance and inclusive education of PWDs in different environmental contexts. Results indicated participants had generally positive affective reactions toward their coworkers with disabilities in the workplace. However, findings also indicated that Vietnamese people possessed hierarchical attitudes toward people with different types of disabilities in terms of community acceptance and educational rights.

Comparing with the metal-oxide-semiconductor field-effect transistor (MOSFET), the switching frequency of the gallium nitride enhancement mode high electron mobility transistor (GaN E-HEMT) can be significantly increased. However, the impacts of parasitic inductance and capacitance to the circuit performance should be taken into account for design considerations. In this paper, the gate drive circuit design for GaN E-HEMT is described in detail. The effectiveness of the design considerations is fully examined by the simulation software, LTSPICE with GaN E-HEMT model introduced by Efficient Power Conversion (EPC). From the simulation results, the parasitic effects caused by the parasitic components can be clearly observed. Thus, the simulation results can provide the insight of practical design. Finally, a buck converter with 1 MHz switching frequency is built according to these design considerations.

This paper proposes a single-stage high-power-factor asymmetrical half-bridge AC-DC converter for power factor correction. The proposed converter is developed by integrating an asymmetrical half-bridge DC-DC converter with a set of coupled inductors and a blocking diode to achieve the single-stage AC-DC conversion with the buck-boost type power factor correction. By using the coupled inductors, the proposed converter can achieve near unity power factor and low total harmonic distortion without using extra switches and control circuits. Thus, the overall efficiency and power density of the AC-DC converter can be improved. The component counts and product cost can also be reduced. Moreover, the proposed converter can achieve zero-voltage switching for both power switches, so the switching loss can be reduced. Hence, the proposed converter has the advantages of near unity PF, low THD, zero-voltage switching, low product cost, and little component counts. A 100W experimental prototype circuit was built to verify the effectiveness of the proposed converter and the experimental results are presented in this paper. The proposed converter achieves a near unity power factor of 0.99 and low THD of 4.95% at 110Vrms line voltage.

A modified asymmetrical half-bridge flyback converter (AHBFC) to fulfill the single-stage buck-type AC-DC adaptor for notebook application is proposed in this paper. The modified AHBFC is obtained from the integration of a buck converter and a conventional AHBFC. The modified AHBFC is operated in the discontinuous conduction mode to achieve the high input power factor to meet the required regulations. Also, the modified AHBFC can achieve the zero voltage switching (ZVS) for the switch and the zero current switching (ZCS) for the output diode to improve the efficiency. Moreover, the transformer's leakage inductor is utilized as the resonant inductor so the circuit structure is further simplified. The operation principles, important characteristics, and equation derivations of the proposed buck-type AC-DC adaptor are explained. A design example of a 100 W prototype is presented. Computer simulation and experimental results with universal input voltage ranges are obtained to verify the performance of the proposed buck-type AC-DC adopter.

Background/PurposeMesh-augmented vaginal surgery for treatment of pelvic organ prolapse (POP) does not meet patients' needs. This study aims to test the hypothesis that fascia tissue engineering using adipose-derived stem cells (ADSCs) might be a potential therapeutic strategy for reconstructing the pelvic floor.MethodsHuman ADSCs were isolated, differentiated, and characterized in vitro. Both ADSCs and fibroblastic-differentiated ADSCs were used to fabricate tissue-engineered fascia equivalents, which were then transplanted under the back skin of experimental nude mice.ResultsADSCs prepared in our laboratory were characterized as a group of mesenchymal stem cells. In vitro fibroblastic differentiation of ADSCs showed significantly increased gene expression of cellular collagen type I and elastin (p

INTRODUCTIONHaving a child who is identified with a disability often comes as a shock with parents experiencing varied psychological impacts (Gupta & Singhal 2004; Summers, Behr, & Turnbull, 1989). Many researchers have pointed out that parents who have children with disabilities often experience feelings of guilt, shame, and embarrassment (Blacher & Hatton, 2001; Kang, Lovett, & Haring, 2002; Lamorey, 2002; Wong, Wong, Martinson, Lai, Chin, & He, 2004). Other researchers have identified several similar emotional stages that parents of children with disabilities may go through (Taylor, 2004). These stages include: shock, denial, anger, sadness, detachment, reorganization, and acceptance (Hornby, 2000). While examining psychological adjustment of parents of children with disabilities is an inpcrtant issue in disability-related studies, other researchers are concentrating their efforts on whether having a child with a disability influences marital relationships.In fact, some professionals have already indicated that having a child with a disability might influence marital relationships in positive, negative, ard mixed directions (Bloom, 1996; Turnbull & Turnbull, 2001). First of all, researchers mentioned that having a child with a disability, including mental retardation, may impair martial relationships due to several factors: unequal distribution of the care-taking tasks, the lack of time for hobbies, and stress concerning children's health (Taanila, Kokkonen, & Jarvelin, 1996; Friedridn & Friedrich, 1981). On the conntrary, many studies showed that having a child with a developmental delay or mental retardation may improve marital relationships (Raghavan, Weisner, & Patel, 1999; Helsel Family, 1985). Having a child with a disability allows couples to understand each other better, to share house work more equally, and to have enhanced opportunities to communicate their stress in order to support one another in providing for the needs of their child with a mental disability.Less significant effects on martial relationships among parents of children with specific disabilities, including Down syndrome, mental retardation, Diabetes mellitus, and motor disability has bean reported (Gau, Chiu, Soong, & Lee, 2008; Taanila et al., 1996). While research results demonstrated varied findings regarding how having a child with a disability can influence marital and overall family relationships, certain variables may mediate the effect. These factors may include: income, temperament of the individuals involved, religious beliefs, time of disability onset, type of disability, and availability of social services (Benson & Gross, 1989; Helsel Family, 1985; Hodapp & Krasner, 1994; Raghavan et al., 1999). Therefore, having a child with a disability influences marital relationships in a complex manner.Studies looking at the interaction patterns and relationships between children with disabilities and their sibling have been ccnducted as well (Harris & Glasberg, 2003; Sharpe & Rossiter, 2002). Similar to their parents, children who grow up with siblings with mental disabilities can also experience favorable, unfavorable, or no noticeable impacts. For instance, researchers stated that assuming caregiving responsibility for siblings with Autism expected by parents could be a stressor for nondisabled children (Lin, Tsai, & Chang, 2008). The feeling of parental favoritism toward their siblings with disabilities, including Down syndrome and mental retardation, is a common phenomenon experienced by children without disabilities (Bischoff & Tingstram, 1991). On the other hand, there was no major impact reported among children who have siblings with mental retardation and Autism (McHale, Sloan, & Simeonsson, 1986).Providing support services, such as group discussion, may assist children in learning how to get along with their siblings who have disabilities as well as help them obtain disabilityrelated knowledge (Dyson, 1998). …

The purpose of this study is to examine and describe the perceptions of Taiwanese mothers who have children with mild to moderate mental retardation as their children enter their teenage years (13-15 years of age). The focus is on whether these mothers' attitudes toward their children and other individuals with disabilities changed after they had experience in raising their own children with disabilities. The results of this qualitative study indicated that having experience in raising children with disabilities led participants to have a more positive outlook toward their children and others with disabilities. In addition, the results of this study demonstrated that the majority of interviewees believed that karma was a factor in their young teenagers being born with disabilities.

This paper developed and implemented automated image mosaicking procedures to produce seamless and smooth mosaics from random sequences of digital aerial images and satellite images. The procedure employs automated algorithms for global image registration, seam line extraction, radiometric adjustment, and composition of overlap images. Results of the experimentation on mosaicking black and white orthorectified aerial images and on mosaicking multi‐resolution color infrared SPOT‐2 and Landsat‐5 satellite images show that the implementation of automated conjugate point extraction and image matching algorithms automates the establishment of geometric registration among overlapped images, while the seam line selection and two‐step lookup table histogram matching approaches facilitate creating globally smooth and qualitative mosaics. The system developed in this paper makes complex composition of multi‐source multi‐resolution multi‐band images with different geometric and radiometric characteristics a...

This study investigated the attitudes of Taiwanese employees toward individuals and their supported coworkers with intellectual disabilities (ID). The findings indicated that the general attitudes of Taiwanese employees toward individuals with ID and their affective reactions toward their coworkers with ID were positive. These discoveries were contrary to previous beliefs that Taiwanese people tended to have societal stigma toward people and coworkers with ID. The outcomes also showed that the participants who had longer work contact with their coworkers with ID tended to have more positive attitudes toward them. Therefore, promoting supported employment trainings and opportunities for qualified people with ID was recommended.

Carbohydrates are the largest natural carbon source when compared to lignin, fatty acids, proteins and other biomass resources. One carbohydrate dehydration product, 5-hydroxymethylfurfural (HMF), is a versatile platform chemical used to derive a number of important C6 compounds, including 2,5-furandicarboxylic acid (FDCA), 2,5-dimethylfuran (DMF), 2,5-diformylfuran (DFF), adipic acid, caprolactone and levulinic acid. Due to structural similarity, FDCA could replace petrochemical-purified terephthalic acid (PTA) for the synthesis of bio-based polyesters to be used for the fabrication of plastic bottles, fibres and films. The oxidation product of HMF, FDCA, is among the original United States Department of Energy's top twelve value-added building blocks. HMF was not on the list because of its lack of high synthetic selectivity and yield. HMF is reactive and can undergo conversion to levulinic acid, humin and other by-products during the dehydration process. Dehydration technology of carbohydrates into HMF has improved since then; in particular, higher yields were realized in ionic liquid media. It is on the ‘Top10 + 4’ revised list of bio-based product opportunities from carbohydrates. This chapter describes the current progress on HMF formation by dehydration of carbohydrates and sugars as well as one-pot direct synthesis of HMF form lignocellulose in ionic liquids.

Neurotoxicities resulting from various medications are under diagnosed; Metronidazole-induced encephalopathy is one of them. Here we present two patients with a history of metronidazole use and discuss neuroimaging findings.We report two patients suffering from acute neurological symptoms associated with metronidazole use. A 70-year-old female who received a cumulative dose of 41.25g of metronidazole within one month, developed seizure. Brain magnetic resonance imaging (MRI) showed T2 hyperintensity over bilateral dentate nuclei and dorsal midbrain. A 56-year-old female suffering from acute onset of central vertigo with metronidazole use, took a total dose of 24g. The brain MRI showed T2 hyperintensity over dorsal midbrain and dorsal medulla, which disappeared in the following neuroimaging 50 days later. Metronidazole-induced encephalopathy (MIE) was suspected in both patients.Metronidazole-induced encephalopathy is an uncommon but potentially reversible disease in patients with acute neurological deficits from the use of metronidazole. Nonalcoholic Wernicke's encephalopathy may share a similar metabolic pathway with MIE, resulting in difficulties in diagnosis.

A low-temperature solution approach (90-95 degrees C) using FeCl(3) and urea was carried out to synthesize beta-FeOOH nanorods in aqueous solution. The as-synthesized beta-FeOOH nanorods were further calcined at 300 degrees C to form porous nanorods with compositions including both beta-FeOOH and alpha-Fe(2)O(3). The derived porous nanorods were engineered to assemble with four layers of polyelectrolytes (polyacrylic acid (PAA)/polyethylenimine(PEI)/PAA/PEI) on their surfaces as polyelectrolyte multilayer nanocapsules. Fluorescein isothiocyanate (FITC) molecules were loaded into the polyelectrolyte multilayer nanocapsules in order to investigate drug release and intracellular delivery in Hela cells. The as-prepared nanocapsules showed ionic strength-dependent control of the permeability of the polyelectrolyte shells. The release behavior of the entrapped FITC from the FITC-loaded nanocapsules exhibited either controlled- or sustained-release trends, depending on the compactness of the polyelectrolyte shells on the nanorod surfaces. Cytotoxicity measurements demonstrate that the native nanorods and the polymer-coated nanorods have excellent biocompatibility in all dosages between 0.1 ng mL(-1) and 100 microgm L(-1). The time dependence of uptake of FITC-loaded nanocapsules by Hela cancer cells observed by laser confocal microscopy indicates that the nanocapsules can readily be taken up by cancer cells in 15 min, a relatively short period of time, while the slow release of the FITC from the initial perimembrane space into the cytoplasm was followed by release into the nucleus after 24 h.