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Thermal dissipation is an important issue for power devices. In this work, the impact of thermal effects on the performance of Cu electroplated GaN-based high-electron-mobility transistors (HEMTs) are considered. Electrical, thermometry and micro-Raman characterization techniques were used to correlate the effects of improved heat dissipation on device performance for GaN HEMTs with different thicknesses of Si substrate (50, 100, 150 μm), with and without an additional electroplated Cu layer. GaN HEMTs on electroplated Cu on Si (≤50 μm) demonstrate an enhanced on/off current ratio compared to bare Si substrate by a factor of ~400 (from 9.61 × 105 to 4.03 × 108). Of particular importance, surface temperature measurements reveal a much lower channel temperature for thinner HEMT devices with electroplated Cu samples compared to those without.

Background Military veterans (veterans, in short), due to their unique military experience, face a variety of health issues either unique to their service or more common than the general population. This study aims to achieve a better understanding of the publications focused on veterans from 1989 to 2018 using a PubMed-based bibliometric analysis of research articles on veterans. Methods We searched the PubMed website for publications in journal article category from 1989 through 2018, indexed with the MeSH descriptor, "Veterans" or "Veterans Health". Recorded articles were retrieved and analyzed. Results During the period 1989-2018, there were 12 710 articles related to veterans or veterans' health, up from 66 articles in 1989 to 1225 articles in 2018. Of all the selected articles, 5242 (41.24%) can be classified under research support by the US government, 2773 (21.81%) by non-US government, and 1700 (13.38%) by the Office of Extramural Research (OER) of the National Institutes of Health. Of the 15 most prolific authors, 14 were affiliated with the US institutions. The journal that published the highest number of articles related to veterans was the journal Military Medicine (504 articles, 3.97%), followed by the Journal of Traumatic Stress (397 articles, 3.12%), Psychiatric Services (Washington, D.C.) (299 articles, 2.35%), and Journal of Rehabilitation Research and Development (279 articles, 2.20%). Among all publications, 18.04% (n = 2293) were published in journals of psychiatry, followed by 13.51% (n = 1717) of psychology and 7.71% (n = 980) of neurology. Conclusion Publications related to veterans increased significantly from 1989 to 2018. A considerable number of the publications were in journals of psychiatric and psychological categories. However, most publications were descriptive of US veterans. Future research related to veterans in Taiwan deserves further exploration to provide a reference for prioritization of the health care and policy making.

In this work, we demonstrate a novel high-power vertical-cavity surface-emitting laser (VCSEL) array with highly single-mode (SM) and single-polarized output performance without significantly increasing the intra-cavity loss and threshold current ( I th). By combining a low-loss zinc-diffusion aperture with an electroplated copper substrate, we can obtain a highly SM output (side mode suppression ratio > 50 d B ) with a very narrow divergence angle ( 1 / e 2 : ∼ 10 ∘ ) under high output power (3.1 W; 1% duty cycle) and sustain a single polarization state, with a polarization suppression ratio of around 9 dB, under the full range of bias currents. Compared to the reference device without the copper substrate, the demonstrated array can not only switch the output optical spectra from quasi-SM to highly SM but also maintain a close threshold current value ( I th: 0.8 versus 0.7 mA per unit device) and slope efficiency. The enhancement in fundamental mode selectivity of our VCSEL structure can be attributed to the single-polarized lasing mode induced by tensile strain, which is caused by the electroplated copper substrate, as verified by the double-crystal x-ray measurement results.

Rapid and efficient detection of viral infection is crucial for the prevention of disease spread during an outbreak and for timely clinical management. In this paper, the utility of Tat peptide-modified molecular beacons (MBs) as a rapid diagnostic tool for the detection of virus-infected cells was demonstrated. The rapid intracellular delivery mediated by the Tat peptide enabled the detection of infected cells within 30 s, reaching saturation in signal in 30 min. This rapid detection scheme was coupled with flow cytometry (FC), resulting in an automated, high-throughput method for the identification of virus-infected cells. Because of the 2-order-of-magnitude difference in fluorescence intensity between infected and uninfected cells, as few as 1% infected cells could be detected. Because of its speed and sensitivity, this approach may be adapted for the practical diagnosis of multiple viral infections.

The trend to use administrative health care databases as research material is increasing but not well explored. Taiwan's National Health Insurance Research Database (NHIRD), one of the largest administrative health care databases around the world, has been used widely in academic studies. This study analyzed 383 NHIRD studies published between 2000 and 2009 to quantify the effects on overall growth, scholar response, and spread of the study fields. The NHIRD studies expanded rapidly in both quantity and quality since the first study was published in 2000. Researchers usually collaborated to share knowledge, which was crucial to process the NHIRD data. However, once the fundamental problem had been overcome, success to get published became more reproducible. NHIRD studies were also published diversely in a growing number of journals. Both general health and clinical science studies benefited from NHIRD. In conclusion, this new research material widely promotes scientific production in a greater magnitude. The experience of Taiwan's NHIRD should encourage national- or institutional-level data holders to consider re-using their administrative databases for academic purposes.

In this study, we describe the use of nuclease-resistant molecular beacons (MBs) for the real-time detection of coxsackievirus B6 replication in living Buffalo green monkey kidney (BGMK) cells via Tat peptide delivery. A nuclease-resistant MB containing 2′- O -methyl RNA bases with phosphorothioate internucleotide linkages was designed to specifically target an 18-bp 5′ noncoding region of the viral genome. For intracellular delivery, a cell-penetrating Tat peptide was conjugated to the MB by using a thiol–maleimide linkage. Presence of the Tat peptide enabled nearly 100% intracellular delivery within 15 min. When the conjugate was introduced into BGMK cell monolayers infected with coxsackievirus B6, a discernible fluorescence was observed at 30 min after infection, and as few as 1 infectious viral particle could be detected within 2 h. The stability and the intracellular delivery properties of the modified MBs enabled real-time monitoring of the cell-to-cell spreading of viral infection. These results suggest that the Tat-modified, nuclease-resistant MBs may be powerful tools for improving our understanding of the dynamic behavior of viral replication and for therapeutic studies of antiviral treatments.

BackgroundNot enough information has been gathered regarding the parameters of color Doppler ultrasonography (CDU) for evaluating diffuse thyroid disorders in Taiwan. The aims of this study were to compare the CDU parameters between the right and left inferior thyroid arteries (ITAs), and to investigate which CDU parameters can differentiate between euthyroid and hyperthyroid glands.Patients and MethodsWe retrospectively reviewed data from patients who had undergone CDU to image thyroid disorders from December 2003 to April 2004 in order to analyze the CDU parameters that can be used to evaluate bilateral ITA. The mean age of the patients was 40.8 ± 16.6 years (range, 10—72 years). The female to male distribution was 2.2:1 (43 females and 20 males). The ITA of patients with normal thyroid, simple goiter and autoimmune thyroid disease were scanned with CDU. The parameters evaluated included pulsatility index (PI), resistive index (RI), peak systolic velocity (PSV), blood volume flow (VF) and diameter (Diam) of ITA. We then evaluated the relationships among these parameters between the right and the left ITAs and differences in parameters between patients with euthyroidism and hyperthyroidism. Significant parameters were analyzed by the t test and simple linear regression.ResultsThere was good Pearson's correlation among all parameters (PI, RI, PSV, VF and Diam) (p < 0.001) between the right and left ITAs in all 63 patients. No significant differences were noted between the right and left ITAs (p > 0.05). These same results were seen in patients with euthyroidism (30 patients) and hyperthyroidism (27 patients), except that Diam of ITA had poor correlation between both sides in the hyperthyroid group. The CDU parameters of ITA were higher in patients with hyperthyroidism than in those with euthyroidism.ConclusionThere were no significant differences in CDU parameters between the right and left ITAs. However, all parameters had higher values in patients with hyperthyroidism than in those with normal thyroid function. Therefore, we conclude that unilateral ITACDU can be used to evaluate diffuse thyroid disorder. A large-scale study is needed to investigate which CDU parameters can be used to differentiate between euthyroid and hyperthyroid status in clinical practice.

The mass transport of methanol mixed with ferric chloride hexahydrate (FeCl3 · 6H2O) in poly(methyl methacrylate) and poly(methyl methacrylate)/iron carbonate particulate(p) nanocomposites is prepared by chemical vapor crystallization and the resulting materials, which are subjected to characterization to evaluate thermal and optical properties, have been investigated. Mass transport is an anomalous and endothermic process and satisfies the van't Hoff plot. We have prepared successfully poly(methyl methacrylate)(PMMA)/iron carbonate particulates nanocomposites using CO2 gas slowly diffused into saturated solvent mixture-treated poly(methyl methacrylate) for 48 h. After SEM observation, approximately 80 nm iron carbonate particulates were precipitated and evenly distributed in the poly(methyl methacrylate) matrix. In comparison with solvent mixture-treated PMMA, the cut-off wavelength of transmittance in nanocomposites shifts to the shorter wavelength side (red shift). The presence of nanoscale iron carbonate particulates increased the glass transition temperature of the nanocomposites as determined by differential scanning calorimeter, and the glass transition temperature increased with increasing content of nanoscale iron carbonate particulates. The FTIR spectra of solvent mixture-treated poly(methyl methacrylate) and nanocomposites are also studied. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2329–2338, 2005

Aims: Human embryonic stem cell-derived cardiomyocytes (hESC-CMs) or mesenchymal stem cells (MSCs) facilitate post-infarct recovery, but the potential benefit of combination therapy using MSCs and hESC-CMs has not been examined. Our objective was to define the gene expression changes in donor and host-derived cells that are induced in vivo after co-transplantation of cardiomyocytes with and without mesenchymal stem cells expressing the prosurvival gene heme oxygenase 1. Methods and results: Human MSCs were engineered to over-express heme oxygenase-1 (HO-1) following lentiviral vector-mediated transduction. Athymic nude rats were subjected to myocardial infarction and received hESC-CMs alone, hESC-CMs plus human MSCs, hESC-CMs plus MSCs overexpressing HO-1, or saline. Real time PCR identified gene expression changes. Cardiac function was assessed by angiography. Co-transplantation of unmodified MSCs plus hESC-CMs elevated CXCR4, HGF, and IGF expression over levels induced by injection of hESC-derived cardiomyocytes alone. In animals co-transplanted with MSC over-expressing HO-1, the expression of these genes was further elevated. Gene expression levels of VEGF, TGF-β, CCL2, SMAD7, STAT3 and cardiomyocyte transcription factors were highest in the HO-1 MSC plus hESC-CM group at 30 days. Human CD31+, CD34+, isl-1+, NXK2.5 and c-kit+ transcripts were elevated. Rodent genes encoding NKX2.5, troponin T and CD31 were elevated and cell cycle genes were induced. Ejection fraction improved by six to seven percent. Conclusions: Co-administration of HO-1 MSCs plus hESC-CMs increased expression of pro-survival and angiogenesis-promoting genes in human cells and transcripts of cardiac and endothelial cell markers in rodent cells, consistent with activation of tissue repair in both transplanted hESC-CMs and the host heart.

Background: Some adolescents have special health care needs. Privacy concerns, unawareness or ethnical/cultural factors are barriers to women visiting obstetricians/gynecologists (OB/GYNs). The utilization of OB/GYN services by adolescent girls is seldom reported. The aim of this study was to investigate the pattern and consequences of first visits to OB/GYNs by adolescent girls within the National Health Insurance in Taiwan. Methods: From the 1-million cohort dataset of the National Health Insurance Research Database spanning from 1996 to 2007, adolescent girls visiting OB/GYNs for the first time were identified. The characteristics of first visits were analyzed. Their follow-up visits and admissions within 1 year after their first visits to OB/GYNs were traced. Results: In 2006, only 5.8% (n = 2,682) of 46,582 adolescent girls in our study cohort had their first visits to OB/GYNs: 46.7% with diagnoses of menstrual disorders and 14.8% with diagnoses related to inflammatory or infectious diseases of the genital organs. The examination most frequently ordered was pregnancy test (for 19.9% of these first visits). Very few (0.4%) first visits were for preventive services. Among the infrequent admissions (85 admissions of 75 girls) to obstetric/gynecology wards within 1 year after first visits, the majority (74 of 85 admissions) were pregnancy-related. Conclusion: The leading motivating factor for first visits to OB/GYNs by adolescent girls was menstrual disorders. The majority of subsequent admissions were pregnancy-related, indicating that adolescent pregnancy deserves further attention. [J Chin Med Assoc 2010;73(3):144–149]

To investigate the patterns of traditional Chinese medicine (TCM) use among pregnant women in the National Health Insurance program in Taiwan.Women who gave birth in Taiwan in 2006 were identified from the National Health Insurance Research Database. Claims for reimbursement following TCM ambulatory visits by these women were analyzed.In total, 20.9% of women in the study who gave birth in 2006 used TCM during pregnancy, with older women more likely to utilize this form of care (23.9% of women35 years of age vs 16.2% of women20 years of age). There was an increase in the use of TCM for pregnancy-related problems such as hypertension (194 women before pregnancy vs 2163 during) and nausea/vomiting (220 women before vs 1648 during). The predominant modality (88.4%) of TCM treatment during pregnancy was herbal preparation.Traditional Chinese medicine, with the exception of acupuncture, is popular among pregnant women in Taiwan. In addition to its efficacy, the safety of TCM during pregnancy requires future investigation.

Waterborne transmitted viruses pose a public health threat due to their stability in aquatic environment and the easy transmission with high morbidity rates at low infectious doses. Two major challenge of virus analysis include a lack of adequate information in infectivity and the inability to cultivate certain epidemiologically important viruses in vitro. The use of fluorescent probes in conjunction with fluorescence microscopy allows us to reveal dynamic interactions of the viruses with different cellular structures in living cells that are impossible to detect by immunological or PCR-based experiments. Real-time viral detection in vivo provides sufficient information regarding multiple steps in infection process at molecular level, which will be valuable for the prevention and control of viral infection.

Multigranularity optical cross-connects (MG-OXCs) have emerged as the means to save the cost of manufacturing large optical cross-connects (OXCs) used in the IP-over-WDM networks. This paper considers the virtual topology configuration problem in the MG-OXC networks that has not yet been studied. We assume that the future traffic pattern is known a priori and we are to reconfigure the original topology, without dramatically changing the current virtual topology, to the new one that is suitable for the new traffic pattern. We propose our heuristic preference based reconfiguration algorithm (PBRA) to solve the problem by constructing an auxiliary graph to help determining the addition, deletion, or keeping of the virtual links. Simulation results show that we can change less original virtual topology at the cost of small increase in blocking probability.

Here we describe a new hybrid fluorescent nanoprobe composed of a nuclease-resistant molecular beacon (MB) backbone, CdSe-ZnS core-shell quantum dots (QDs) as donors, and gold nanoparticles (Au NPs) as quenchers, for the real-time visualization of virus replication in living cells. By using a Au NP-MB to QD ratio of 6 : 1, a 7.3-fold increase in fluorescent signal was achieved upon target binding. For living cell experiments, a hexahistidine-appended Tat peptide was self-assembled onto the QD surface to provide nearly 100% non-invasive delivery of the QD-MB-Au NP probes within 2 h. By directly visualizing the fluorescent complexes formed with the newly synthesized viral RNA, this QD-MB-Au NP probe provided sensitive and real-time detection of infectious viruses as well as the real-time visualization of cell-to-cell virus spreading.