Protonated polyaniline (PANI) is directly polymerized on Nafion 117 (N117), forming a composite membrane, to act as a methanol-blocking layer to reduce the methanol crossover in the direct methanol ...fuel cell (DMFC), which is beneficial for the DMFC operating at high methanol concentration. The PANI layer grown on the N117 with a thickness of 100
nm has an electrical conductivity of 13.2
S
cm
−1. The methanol permeability of the PANI/N117 membrane is reduced to 59% of that of the N117 alone, suggesting that the PANI/N117 can effectively reduce the methanol crossover in the DMFC. Comparison of membrane-electrode-assemblies (MEA) using the conventional N117 and the newly developed PANI/N117 composite shows that the PANI/N117-based MEA outputs higher power at high methanol concentration, while the output power of the N117-based MEA is reduced at high methanol concentration due to the methanol crossover. The maximum power density of the PANI/N117-based MEA at 60
°C is 70
mW
cm
−2 at 6
M methanol solution, which is double the N117-based MEA at the same methanol concentration. The resistance of PANI/N117 composite membrane is reduced at elevated methanol concentration, due to the hydrogen bonding between methanol and PANI pushes the polymer chains apart. It is concluded that the PANI/N117-based MEA performs well at elevated methanol concentration, which is suitable for the long-term operation of the DMFC.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Optical reflection, or in other words the loss of reflection, from a surface becomes increasingly crucial in determining the extent of the light-matter interaction. The simplest example of using an ...anti-reflecting (AR) surface is possibly the solar cell that incorporates an AR coating to harvest sunlight more effectively. Researchers have now found ways to mimic biological structures, such as moth eyes or cicada wings, which have been used for the AR purpose by nature herself. These nanoscopic biomimetic structures lend valuable clues in fabricating and designing gradient refractive index materials that are efficient AR structures. The reflectance from a selected sub-wavelength or gradient index structures have come down to below 1% in the visible region of the spectrum and efforts are on to achieve broader bands of such enhanced AR regime. In addition to the challenge of broader bands, the performance of AR structures is also limited by factors such as omnidirectional properties and polarization of incident light. This review presents selected state-of-the-art AR techniques, reported over the last half a century, and their guiding principles to predict a logical trend for future research in this field.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Infection by hepatitis B virus (HBV) accounts for 50-80% of hepatocellular carcinoma (HCC) development worldwide, in which the HBV-encoded X protein (HBx) has critical role in the induction of ...carcinogenesis. Several studies have shown that thyroid hormone (TH) suppresses HCC development and protects hepatocytes from HBx-induced damage, thus it is of interest to examine whether TH can protect hepatocytes from HBx-induced carcinogenesis. By treating HBx- transgenic mice with or without TH, we confirmed the protective effects of TH on HBx-induced hepatocarcinogenesis, which was achieved via reduction of reactive oxygen species (ROS) inflicted DNA damage. We further found that TH induced biogenesis of mitochondria (MITO) and autophagy of HBx-targeted MITO simultaneously, consequently leading to suppression of HBx-promoted ROS and carcinogenesis. Using microarray data analysis, this protective effect of TH was found to be mediated via activation of PTEN-induced kinase 1 (PINK1) in hepatocytes. PINK1, in turn, activated and recruited Parkin, an E3 ligase, to ubiquitinate MITO-associated HBx protein and trigger selective mitophagy. The pathological significance of the TH/PINK1 pathway in liver protection was confirmed by the concomitant decrease in expression of both TR and PINK1 in matched HCC tumor tissues and negatively correlated with aggressive progression of cancer and poor prognosis. Our data indicate that TH/PINK1/Parkin pathway has a critical role in protecting hepatocytes from HBx-induced carcinogenesis. Notably, several liver-targeting therapeutic derivatives of TH facilitating prevention or therapy of steatosis have been identified. Furthermore, our proof-of-concept experiments suggest that application of T
constitutes an effective novel therapeutic or preventive option for HCC. Thus, the utilization of the agonists of TRs could be the meaningful strategy in liver relative diseases, ranging from simple hepatic steatosis to HCC.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
To describe the infection control preparedness measures undertaken for coronavirus disease (COVID-19) due to SARS-CoV-2 (previously known as 2019 novel coronavirus) in the first 42 days after ...announcement of a cluster of pneumonia in China, on December 31, 2019 (day 1) in Hong Kong.
A bundled approach of active and enhanced laboratory surveillance, early airborne infection isolation, rapid molecular diagnostic testing, and contact tracing for healthcare workers (HCWs) with unprotected exposure in the hospitals was implemented. Epidemiological characteristics of confirmed cases, environmental samples, and air samples were collected and analyzed.
From day 1 to day 42, 42 of 1,275 patients (3.3%) fulfilling active (n = 29) and enhanced laboratory surveillance (n = 13) were confirmed to have the SARS-CoV-2 infection. The number of locally acquired case significantly increased from 1 of 13 confirmed cases (7.7%, day 22 to day 32) to 27 of 29 confirmed cases (93.1%, day 33 to day 42; P < .001). Among them, 28 patients (66.6%) came from 8 family clusters. Of 413 HCWs caring for these confirmed cases, 11 (2.7%) had unprotected exposure requiring quarantine for 14 days. None of these was infected, and nosocomial transmission of SARS-CoV-2 was not observed. Environmental surveillance was performed in the room of a patient with viral load of 3.3 × 106 copies/mL (pooled nasopharyngeal and throat swabs) and 5.9 × 106 copies/mL (saliva), respectively. SARS-CoV-2 was identified in 1 of 13 environmental samples (7.7%) but not in 8 air samples collected at a distance of 10 cm from the patient's chin with or without wearing a surgical mask.
Appropriate hospital infection control measures was able to prevent nosocomial transmission of SARS-CoV-2.
Central venous catheters (CVCs) are frequently used for monitoring haemodynamic status and rapidly delivering fluid therapy during the peri- and postoperative periods. Indwelling CVCs are typically ...used 7–14 days postoperatively for additional monitoring and treatment, but patients may develop asymptomatic catheter-related thrombosis, leading to life-threatening pulmonary embolism and death. Early detection helps to avoid such complications.
This prospective observational study investigated the risk factors associated with catheter-related right internal jugular vein thrombosis in patients undergoing chest surgery. The study enrolled 24 patients who were scheduled to receive chest surgeries during which catheters were needed. To detect thrombus formation, Doppler ultrasound examinations from the thyroid cartilage level to the supraclavicular region were used after CVC placement and on each of the following days until the catheter was removed.
No thrombosis was found in patients before surgery, but it appeared in 75% (18/24) after surgery. The risks of thrombosis increased with a longer duration of anaesthesia, greater amounts of bleeding, and use of postoperative ventilator support.
Earlier catheter removal may reduce the risk of catheter-related thrombosis and avoid possibly fatal complications after catheter-related thrombosis.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The long-term outcome of 1390 children with acute lymphoblastic leukemia (ALL), treated in two successive clinical trials (Taiwan Pediatric Oncology Group (TPOG)-ALL-97 and TPOG-ALL-2002) between ...1997 and 2007, is reported. The event-free survival improved significantly (P=0.0004) over this period, 69.3+/-1.9% in 1997-2001 to 77.4+/-1.7% in 2002-2007. A randomized trial in TPOG-97 testing L-asparaginase versus epidoxorubicin in combination with vincristine and prednisolone for remission induction in standard-risk (SR; low-risk) patients yielded similar outcomes. Another randomized trial, in TPOG-2002, showed that for SR patients, two reinduction courses did not improve long-term outcome over one course. Decreasing use of prophylactic cranial irradiation in the period 1997-2008 was not associated with increased rates of CNS relapse, prompting complete omission of prophylactic cranial irradiation from TPOG protocols, beginning in 2009. Decreased use of etoposide and cranial irradiation likely contributed to the low incidence of second cancers. High-risk B-lineage ALL, T-cell, CD10 negativity, t(9;22), infant, and higher leukocyte count were consistently adverse factors, whereas hyperdiploidy >50 was a consistently favorable factor. Higher leukocyte count and t(9;22) retained prognostic significance in both TPOG-97 and TPOG-2002 by multivariate analysis. Although long-term outcome in TPOG clinical trials is comparable with results being reported worldwide, the persistent strength of certain prognostic variables and the lower frequencies of favorable outcome predictors, such as ETV6-RUNX1 and hyperdiploidy >50, in Taiwanese children warrant renewed effort to cure a higher proportion of patients while preserving their quality of life.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Background: To clarify the role of intention to treat for patients with localized nasal natural killer (NK)/T-cell lymphoma, and to determine the prognostic factors for these patients. Patients and ...methods: We conducted a retrospective review of 46 patients with localized nasal NK/T-cell lymphomas treated at a single institute between January 1988 and July 2002. Results: The type of intended treatment was a significant factor for overall survival (OS) (5-year OS: RT versus CT = 83.3% versus 28.6%, P = 0.0269) or failure-free survival (FFS) (5-year FFS: RT versus CT = 83.3% versus 27.1%, P = 0.0247). In the intended chemotherapy group, salvage with radiotherapy was superior to chemotherapy alone for OS (5-year OS: 42.2% versus 20.0%, P = 0.0252) or FFS (5-year FFS: 41.0% versus 20.0%, P = 0.0352). On multivariate analysis, both N stage and serum lactate hehydrogenase level were independent factors for OS and FFS. No radiotherapy was an independent adverse factor for OS; advanced T stage and more than one extranodal involvement were independent adverse factors for FFS. Conclusions: Patients with localized nasal NK/T-cell lymphomas were better managed with radiotherapy as front-line therapy. The advantage of radiotherapy persisted even as palliative therapy after chemotherapy.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The effects of Zr, Er and Cr additions on the microstructures, mechanical properties and corrosion resistance of Al–Zn–Mg–Cu alloy were investigated. The combined additions of Zr, Er and Cr to ...Al–Zn–Mg–Cu alloy led to the formation of coherent Zn, Mg, Cu, Cr-containing Al3(Zr, Er). These 15–25nm secondary precipitates remarkably inhibited the recrystallization of Al matrix, and numerous fine subgrain boundaries were retained. Compared to the partial recrystallized Al–Zn–Mg–Cu–Zr alloy, the unrecrystallized Al–Zn–Mg–Cu–Zr–Er–Cr alloy exhibited higher resistance to intergranular corrosion and stress corrosion with the improved mechanical properties and fracture toughness. The synergetic effects of Zr, Er and Cr on the precipitates, recrystallization and corrosion resistance of ultra-high strength Al–Zn–Mg–Cu alloys have been discussed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The nature of subproton scale fluctuations in the solar wind is an open question, partly because two similar types of electromagnetic turbulence can occur: kinetic Alfvén turbulence and whistler ...turbulence. These two possibilities, however, have one key qualitative difference: whistler turbulence, unlike kinetic Alfvén turbulence, has negligible power in density fluctuations. In this Letter, we present new observational data, as well as analytical and numerical results, to investigate this difference. These results show, for the first time, that the fluctuations well below the proton scale are predominantly kinetic Alfvén turbulence, and, if present at all, the whistler fluctuations make up only a small fraction of the total energy.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
To evaluate the refractive outcomes in children treated after intravitreal injection of bevacizumab (IVB) for retinopathy of prematurity (ROP).
A retrospective, bi-centre study of 34 patients (64 ...eyes) was conducted. The patients were divided into three groups, patients received intravitreal IVB (IVB group), patients received combined IVB and laser treatment (IVB + Laser group), or patients received lens-sparing vitrectomy (IVB + LSV group). Cycloplegic refraction and axial length (AXL) were evaluated at 2 years old.
The prevalences of myopia and high myopia were 47.5 and 10.0% in the IVB group, respectively, which were lower than those in the IVB + Laser (82.4 and 29.4%) and IVB + LSV (all 100%) groups (P = 0.001 and P < 0.001). The prevalences of emmetropia in the IVB group, IVB + Laser group, and IVB + LSV group were 50, 5.9, and 0% (P = 0.001). The AXL were similar among all groups.
At the 2-year follow-up, severe ROP patients treated with IVB alone were more likely to remain emmetropic and had lower prevalences of myopia and high myopia. The development of high myopia in severe ROP patients could not be explained by AXL changes but may be associated with abnormalities in the anterior segment.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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