Electrochromic Polymers Based on 1,4-Bis((9H-carbazol-9-yl)methyl)benzene and 3,4-Ethylenedioxythiophene Derivatives as Promising Electrodes for Flexible Electrochromic Devices

A 1,4-bis((9H-carbazol-9-yl)methyl)benzene (DCB)-containing homopolymer (P(DCB)) and four DCB- and ED-derivative (3,4-ethylenedioxythiophene (EDOT) and 3,4-ethylenedioxythiophene-methanol (EDm))-containing copolymers (P(DCB-co-ED), P(2DCB-co-ED), P(DCB-co-EDm), and P(2DCB-co-EDm)) were electropolymerized on ITO-polyethylene terephthalate (PET) substrates and their electrochromic performances were studied. DCB displays a lower Eonset than that of EDOT and EDm, conjecturing that the biscarbazole-containing DCB group shows a stronger electron-donating property than that of the ED derivatives. The P(2DCB-co-ED) film presents slate grey, dark khaki, and dark olive green at 0.0, 1.0, and 1.2 V. Bleaching-to-coloring switching studies of polymers show that P(2DCB-co-EDm) shows a high ΔT (31.0% at 725 nm) in solutions. Five dual-layer flexible electrochromic devices (ECDs) based on P(DCB), P(DCB-co-ED), P(2DCB-co-ED), P(DCB-co-EDm), and P(2DCB-co-EDm) as the anodic materials and PEDOT-PSS as the cathodic material are constructed. The P(2DCB-co-ED)/PEDOT-PSS flexible ECD shows a high ΔT (40.3% at 690 nm) and long-term electrochemical cycling stability, while the P(DCB-co-EDm)/PEDOT-PSS ECD shows a high ΔT (39.1% at 640 nm) and short response time (≤1.5 s). These findings offer us a new structural insight for the valuable design of conjugated polymers in high-contrast, flexible ECDs

PEDF Promotes Self-Renewal of Limbal Stem Cell and Accelerates Corneal Epithelial Wound Healing

Limbal epithelial stem cell (LSC) transplantation is a prevalent therapeutic method for patients with LSC deficiency. The maintenance of stem cell characteristics in the process of culture expansion is critical for the success of ocular surface reconstruction. Pigment epithelial-derived factor (PEDF) increased the numbers of holoclone in LSC monolayer culture and preserved the stemness of LSC in suspension culture by evidence of Np63, Bmi-1, and ABCG2 expression. BrdU pulse-labeling assay also demonstrated that PEDF stimulated LSCs proliferation. In air-lift culture of limbal equivalent, PEDF was capable of increasing the numbers of Np63-positive cells. The mitogenic effect of PEDF was found to be mediated by the phosphorylations of p38 MAPK and STAT3 in LSCs. Synthetic 44-mer PEDF (residues 78-121) was as effective as the full length PEDF in LSC expansion in suspension culture and limbal equivalent formation, as well as the activation of p38 MAPK and STAT3. In mice subjecting to mechanical removal of cornea epithelium, 44-mer PEDF facilitated corneal wound healing. Microscopically, 44-mer PEDF advanced the early proliferative response in limbus, increased the proliferation of Np63-positive cells both in limbus and in epithelial healing front, and assisted the repopulation of limbus in the late phase of wound healing. In conclusion, the capability of expanding LSC in cell culture and in animal indicates the potential of PEDF and its fragment (e.g., 44-mer PEDF) in ameliorating limbal stem cell deficiency; and their uses as therapeutics for treating corneal wound. STEM Cells2013;31: 1775-178

Electrochromic Devices Based on Poly(2,6-di(9H-carbazol-9-yl)pyridine)-Type Polymer Films and PEDOT-PSS

2,6-Di(9H-carbazol-9-yl)pyridine (DiCP) was synthesized and its corresponding homopolymer (PDiCP) and copolymers (P(DiCP-co-CPDT), P(DiCP-co-CPDT2), P(DiCP-co-CPDTK), and P(DiCP-co-CPDTK2)) were synthesized electrochemically. The anodic copolymer with DiCP:cyclopentadithiophene ketone (CPDTK) = 1:1 feed molar ratio showed high transmittance change (ΔT%) and colouration efficiency (η), which were measured as 39.5% and 184.1 cm2 C−1 at 1037 nm, respectively. Electrochromic devices (ECDs) were composed of PDiCP, P(DiCP-co-CPDT), P(DiCP-co-CPDT2), P(DiCP-co-CPDTK), and P(DiCP-co-CPDTK2) as anodically-colouring polymers, and poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonic acid) (PEDOT-PSS) as cathodically-colouring polymers. P(DiCP-co-CPDTK)/PEDOT-PSS ECD showed light silverish-yellow at 0.0 V, light grey at 0.7 V, grey at 1.3 V, light greyish blue at 1.7 V, and greyish blue at 2.0 V. Moreover, P(DiCP-co-CPDTK)/PEDOT-PSS ECD presented high ΔT (38.2%) and high η (633.8 cm2 C−1) at 635 nm

Effects of short-term oral anticoagulation following surgical bioprosthetic aortic valve replacement

Background: Short-term oral anticoagulation (OAC) is recommended for patients after surgical bioprosthetic aortic valve replacement (bAVR); however, the potential benefits remain controversial. This study evaluated the effects of short-term OAC following bAVR. Methods: From 2010 to 2017, total 450 patients who underwent bAVR were enrolled. The outcomes of patients who did (OAC group) and who did not receive OAC (without-OAC group) after bAVR were compared. Propensity-score matching (PSM) was used to adjust for potential confounders, and a 1:1 matched cohort was formed. The main outcomes were all-cause mortality and bioprosthetic valve dysfunction (BVD). Results: A total of 175 (39%) patients received OAC after bAVR. The median follow-up period was 2.9 years, the median duration of OAC use was 4 months; 162 pairs of patients were identified after the PSM. There was no significant difference in the prevalence of 1-year embolism/ischemic stroke between the OAC and without-OAC group in PSM cohort (0.62% vs. 1.89% for embolism, p = 0.623; 0 vs. 1.23% for ischemic stroke, p = 0.499). The prevalence of 1-year intracranial hemorrhage (ICH) between OAC and without-OAC group was also comparable (0.62% vs. 0.62%, p = 1). The OAC group had a lower all-cause mortality (adjusted hazard ratio (aHR):0.488, 95% confidence interval (CI): 0.259–0.919). There was also a trend for reduced BVD in the OAC group (aHR: 0.661, 95% CI: 0.339–1.290). Conclusion: Our study demonstrated that short-term OAC use after bAVR was associated with lower all-cause mortality. The prevalence of 1-year embolism/ischemic stroke/ICH were comparable despite of OAC use

Preparation of Advanced Carbon Anode Materials from Mesocarbon Microbeads for Use in High C-Rate Lithium Ion Batteries

Mesophase soft carbon (MSC) and mesophase graphite (SMG), for use in comparative studies of high C-rate Lithium Ion Battery (LIB) anodes, were made by heating mesocarbon microbeads (MCMB) at 1300 °C and 3000 °C; respectively. The crystalline structures and morphologies of the MSC, SMG, and commercial hard carbon (HC) were investigated by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and Raman spectroscopy. Additionally, their electrochemical properties, when used as anode materials in LIBs, were also investigated. The results show that MSC has a superior charging rate capability compared to SMG and HC. This is attributed to MSC having a more extensive interlayer spacing than SMG, and a greater number of favorably-oriented pathways when compared to HC

Appendectomy timing: Will delayed surgery increase the complications?

Background: This study investigated whether the time from emergency room registration to appendectomy (ETA) would affect the incidence of perforation and postoperative complications in patients with acute appendicitis. Methods: Patients who underwent an appendectomy at the Ren-Ai branch of Taipei City Hospital between January 2010 and October 2012 were retrospectively reviewed. Their demographics, white blood cell count, C-reactive protein, body temperature, computed tomography scan usage, operation method, pathology report, postoperative complication, length of hospital stay, and ETA were abstracted. Multivariate analysis was performed to search the predictors, including ETA, of outcomes for the perforation and postoperative complication rates. Results: A total of 236 patients were included in the study. Perforation occurred in 12.7% (30/236) and postoperative complications developed in 24.1% (57/236) of these patients. There were 121 patients with ETA <8 hours, 88 patients with ETA of 8–24 hours, and 27 patients with ETA >24 hours; patients with ETA >24 hours had significantly longer hospital stay. Univariate analysis showed that perforated patients were significantly older, and had higher C-reactive protein level, longer hospital stay, and higher complication rate. Patients who developed postoperative complications were significantly older, and had higher neutrophil count, less use of computed tomography, and higher open appendectomy rate. After multivariate analysis, age ≥55 years was the only predictor for perforation [odds ratio (OR) = 3.65; 95% confidence interval (CI), 1.54–8.68]; for postoperative complications, age ≥55 years (OR = 1.65; 95% CI, 1.84–3.25), perforated appendicitis (OR = 3.17; 95% CI, 1.28–7.85), and open appendectomy (OR = 3.21; 95% CI, 1.36–7.58) were associated. ETA was not a significant predictor in both analyses. Conclusion: In our study, it was observed that although longer ETA was associated with longer hospitalization, ETA was not correlated with postoperative complications. Our results inclined toward the position that appendectomy can be performed as a semielective surgery

The subject-dependent, cumulative, and recency association of aerobic fitness with academic performance in Taiwanese junior high school students

Abstract Background The objective of the current study was to examine whether the relation between aerobic fitness and academic achievement during adolescence is subject-dependent, and to investigate cumulative and recency effects. Methods This study made use of two nationwide datasets. The first was the aerobic fitness profile of junior high school students collected by the Ministry of Education in Taiwan. The second contained the scores on the Basic Competence Test for Junior High School Students (BCTJH). The sample consisted of 382,259 students who completed the BCTJH in the 5 years between 2009 and 2013. Data on each student’s aerobic fitness during their three years of junior high school were matched with their exam results at the end of this period. Results The results revealed that students classified as highly-fit during at least one of the three years had higher BCTJH scores than those who never achieved this level, with the size of effect increasing with the length of time that fitness was maintained. Additionally, aerobic fitness in the final year was more closely linked to BCTJH scores than that in the earlier two years. Fitness was also more strongly associated with exam performance in math, science and social science, relative to language-related subjects. Conclusions Our findings suggest that while aerobic fitness is positively related to academic achievement in Taiwanese junior high school students, the relationship depends on academic subject, as well as the length and time of being aerobically fit

RESEARCH Open Access PGASO: A synthetic biology tool for engineering a cellulolytic yeast

Background: To achieve an economical cellulosic ethanol production, a host that can do both cellulosic saccharification and ethanol fermentation is desirable. However, to engineer a non-cellulolytic yeast to be such a host requires synthetic biology techniques to transform multiple enzyme genes into its genome. Results: A technique, named Promoter-based Gene Assembly and Simultaneous Overexpression (PGASO), that employs overlapping oligonucleotides for recombinatorial assembly of gene cassettes with individual promoters, was developed. PGASO was applied to engineer Kluyveromycesmarxianus KY3, which is a thermo- and toxin-tolerant yeast. We obtained a recombinant strain, called KR5, that is capable of simultaneously expressing exoglucanase and endoglucanase (both of Trichodermareesei), a beta-glucosidase (from a cow rumen fungus), a neomycin phosphotransferase, and a green fluorescent protein. High transformation efficiency and accuracy were achieved as ~63 % of the transformants was confirmed to be correct. KR5 can utilize beta-glycan, cellobiose or CMC as the sole carbon source for growth and can directly convert cellobiose and beta-glycan to ethanol. Conclusions: This study provides the first example of multi-gene assembly in a single step in a yeast species other than Saccharomyces cerevisiae. We successfully engineered a yeast host with a five-gene cassette assembly and the new host is capable of co-expressing three types of cellulase genes. Our study shows that PGASO is an efficient tool for simultaneous expression of multiple enzymes in the kefir yeast KY3 and that KY3 can serve as a host for developing synthetic biology tools

PGASO: A synthetic biology tool for engineering a cellulolytic yeast

Background: To achieve an economical cellulosic ethanol production, a host that can do both cellulosic saccharification and ethanol fermentation is desirable. However, to engineer a noncellulolytic yeast to be such a host requires synthetic biology techniques to transform multiple enzyme genes into its genome. Results: A technique, named Promoter-based Gene Assembly and Simultaneous Overexpression (PGASO), that employs overlapping oligonucleotides for recombinatorial assembly of gene cassettes with individual promoters, was developed. PGASO was applied to engineer Kluyveromycesmarxianus KY3, which is a thermo- and toxin-tolerant yeast. We obtained a recombinant strain, called KR5, that is capable of simultaneously expressing exoglucanase and endoglucanase (both of Trichodermareesei ), a beta-glucosidase (from a cow rumen fungus), a neomycin phosphotransferase, and a green fluorescent protein. High transformation efficiency and accuracy were achieved as ~63% of the transformants was confirmed to be correct. KR5 can utilize beta-glycan, cellobiose or CMC as the sole carbon source for growth and can directly convert cellobiose and beta-glycan to ethanol. Conclusions: This study provides the first example of multi-gene assembly in a single step in a yeast species other than Saccharomyces cerevisiae . We successfully engineered a yeast host with a five-gene cassette assembly and the new host is capable of co-expressing three types of cellulase genes. Our study shows that PGASO is an efficient tool for simultaneous expression of multiple enzymes in the kefir yeast KY3 and that KY3 can serve as a host for developing synthetic biology tools