A series of donor–acceptor–donor triazine‐based molecules with thermally activated delayed fluorescence (TADF) properties were synthesized to obtain highly efficient blue‐emitting OLEDs with ...non‐doped emitting layers (EMLs). The targeted molecules use a triazine core as the electron acceptor, and a benzene ring as the conjugated linker with different electron donors to alternate the energy level of the HOMO to further tune the emission color. The introduction of long alkyl chains on the triazine core inhibits the unwanted intermolecular D–D/A–A‐type π–π interactions, resulting in the intermolecular D–A charge transfer. The weak aggregation‐caused quenching (ACQ) effect caused by the suppressed intermolecular D–D/A–A‐type π–π interaction further enhances the emission. The crowded molecular structure allows the electron donor and acceptor to be nearly orthogonal, thereby reducing the energy gap between triplet and singlet excited states (ΔEST). As a result, blue‐emitting devices with TH‐2DMAC and TH‐2DPAC non‐doped EMLs showed satisfactory efficiencies of 12.8 % and 15.8 %, respectively, which is one of the highest external quantum efficiency (EQEs) reported for blue TADF emitters (λpeak<475 nm), demonstrating that our tailored molecular designs are promising strategies to endow OLEDs with excellent electroluminescent performances.
Getting the blues: A series of donor–acceptor–donor triazine‐based molecules with thermally activated delayed fluorescence (TADF) properties were synthesized to obtain highly efficient blue‐emitting OLEDs with non‐doped emitting layers (EMLs). The targeted molecules use a triazine core as the electron acceptor, and a benzene ring as the conjugated linker with different electron donors to alternate the energy level of the HOMO to further tune the emission color.
Two novel bipolar host materials based on carbazole and triarylborane moieties, i.e. B-2CZ and m-B-CZ, are synthesized and characterized. The spatially crowded compound B-2CZ exhibits a high thermal ...stability (Td > 340 °C) compared to the reported triarylboryl carbazoles, presumably due to the highly compact architecture. As a result, phosphorescent Ir(ppy)3 combined with both the borylated compounds is selected to construct a host-guest system. Devices A (B-2CZ) and B (m-B-CZ) achieve peak efficiencies of 19.3% (69.1 cd/A and 88.1 lm/W) and 19.1% (66.1 cd/A and 77.2 lm/W), respectively. The respective turn-on voltages of devices A and B are recorded at 2.4 and 2.6 V, which are much lower than that of device with the benchmark host (mCP, 3.3 V). In addition, at a higher practical luminance of 100 cd/m2 (1000 cd/m2), the external quantum efficiencies of devices A and B are still preserved at 19.1% (17.3%) and 18.2% (13.0%) with the mitigated efficiency drops of 1% (10%) and 5% (32%), suggesting the promising advantage for realizing efficient phosphorescent organic light-emitting devices.
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•Novel bipolar host materials, i.e. B-2CZ and m-B-CZ, exhibit a high thermal stability (B-2CZ, Td > 340 °C) compared to most reported triarylboryl carbazoles due to the spatially crowded and compact architecture.•The respective turn-on voltages of devices A and B are recorded at 2.4 and 2.6 V, which are much lower than that of devices with the conventional host (mCP, 3.3 V) and the reported triarylboryl-substituted carbazoles.•Devices A (B-2CZ) and B (m-B-CZ) achieve peak efficiencies of 19.3% (69.1 cd/A and 88.1 lm/W) and 19.1% (66.1 cd/A and 77.2 lm/W), respectively.
Imatinib (IM) is a first-line therapeutic drug for chronic myeloid leukemia (CML), a hematological disease. Mutations in the BCR-ABL domain increase formation of IM resistance in CML. However, not ...all patients are BCR-ABL domain-mutant dependent. Investigating non-mutant mechanisms in the development of acquired IM resistance is a critical issue. We explored the mechanisms which influence IM efficacy and resistance in CML. Higher protective autophagy was identified in IM-resistant K562 (K562R) cells. Inhibition of autophagy by the inhibitors, chloroquine and 3-methyladenine, enhanced IM's efficacy in K562R cells. In addition, microRNA (miR)-199a/b-5p were downregulated in K562R cells compared to parent cells. Overexpression of miR-199a/b-5p reduced autophagy and induced cell apoptosis, resulting in enhanced IM's efficacy in K562R cells. Moreover, expression levels of the Wingless-type MMTV integration site family member 2 (WNT2), a positive regulator of autophagy, were significantly higher in K562R cells, and it was validated as a direct target gene of miR-199a/b-5p. Overexpressions of miR-199a/b-5p inhibited WNT2 downstream signaling. Furthermore, overexpression and knockdown of WNT2 influenced autophagy formation and CML drug sensitivity to IM. Overexpression of WNT2 could also reverse miR-199a/b-5p-enhanced IM efficacy in K562R cells. These results emphasized that miR-199a/b-5p inhibited autophagy via repressing WNT2 signaling and might provide novel therapeutic strategies for future IM-resistant CML therapy and drug development.
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•Protective autophagy inhibited imatinib efficacy in CML cells.•miR-199a/b-5p reduced autophagy and enhanced imatinib efficacy.•WNT2 was identified as a direct target gene of miR-199a/b-5p.•Changes in WNT2 levels influenced autophagy formation and imatinib sensitivity.•Overexpression of WNT2 reversed miR-199a/b-5p-enhanced imatinib efficacy.
A series of charge-neutral bis-tridentate Ir(III) complexes (1, 3, and 4) were prepared via employing three distinctive tridentate prochelates, that is, (pzptBphFO)H2, (phpyim)H2·(PF6), and ...(pimb)H3·(PF6)2, which possess one dianionic pzptBphFO, together with a second monoanionic tridentate chelate, namely, (pzptBphFO)H, phpyim, and pimb, respectively. Moreover, a homoleptic, charge-neutral complex 2 was obtained by methylation of chelating (pzptBphFO)H of 1 in basic media, while closely related cationic complexes 5–7 were obtained by further methylation of the remaining pyrazolate unit of previously mentioned neutral complexes 2–4, followed by anion metatheses. All of these Ir(III) metal complexes showed a broadened emission profile with an onset at ∼450 nm, a result of an enlarged ligand-centered ππ* transition gap, but with distinct efficiencies ranging from 0.8% to nearly unity. Comprehensive spectroscopic and computational approaches were executed, providing a correlation for the emission efficiencies versus energy gaps and between the metal-to-ligand charge transfer/ππ* emitting excited state and upper-lying metal-centered dd quenching state. Furthermore, Ir(III) complexes 3 and 4 were selected as dopant emitters in the fabrication of sky-blue phosphorescent organic light-emitting diodes, affording maximum external quantum efficiencies of 16.7 and 14.6% with CIE x,y coordinates of (0.214, 0.454) and (0.191, 0.404) at a current density of 102 cd/m2, respectively. Hence, this research highlights an inherent character of bis-tridentate Ir(III) complexes in achieving high phosphorescence quantum yield at the molecular level.
Introduction
Although antifungal supplementation reduces the fungal load in the corneal storage medium, consensus is lacking on the influence of dosing and temperature. The study aims to evaluate the ...impact of eye bank warming protocol and timing of antifungal supplements on efficacy in Optisol-GS and tissue.
Methods
Corneoscleral rims contaminated with
Candida albicans
(
C. albicans
) were incubated in Optisol-GS, either without antifungal agents or with the addition of amphotericin B or voriconazole at various concentrations (2 ×, 5 ×, 10 ×, and 20 × MIC), at different time points, and under various preservation temperatures (2–8 °C versus 2 h-room temperature exposure). Antifungal efficacy was evaluated by counting viable yeast colonies cultured from Optisol-GS samples. Tissue sterility was determined through direct tissue culture and histological examination of the contaminated rims after a 14-day incubation period.
Results
Room temperature exposure did not increase colony growth at the same multiple MIC of antifungal agents. Although antifungal addition reduced
C. albicans
growth in a concentration-dependent manner, yeast growth was still observed in all Optisol-GS samples with a single supplementation after a 14-day incubation. Only groups with additional antifungal supplementation on either day 2 or day 6 showed a 99% or greater reduction of
C. albicans
growth in Optisol-GS samples and yielded negative results in direct tissue culture.
Conclusions
The eye bank warming protocol did not compromise antifungal efficacy. To sustain the required concentration and effectively reduce
C. albicans
growth in Optisol-GS and contaminated tissue, additional antifungal supplementation on either day 2 or day 6 was necessary during a 2-week preservation period.
1 Graduate Institute of Rehabilitation Science and Center for Healthy Aging Research, Chang Gung University, Tao-Yuan; and ;
2 Department of Physical Therapy, Dachien General Hospital, Miaoli, Taiwan
...Submitted 23 March 2009
; accepted in final form 24 July 2009
Phagocytosis and oxidative burst are critical host defense mechanisms in which neutrophils clear invading pathogens. Clearing phagocytic neutrophils by triggering apoptosis is an essential process for controlling inflammation. This study elucidates how various exercise bouts with/without hypoxia affected neutrophil bactericidal activity and subsequent apoptosis in humans. Fifteen sedentary males performed six distinct experimental tests in an air-conditioned normobaric hypoxia chamber: two normoxic exercises strenuous exercise (SE; up to maximal O 2 consumption) and moderate exercise (ME; 50% maximal O 2 consumption for 30 min) while exposed to 21% O 2 , two hypoxic exercises (ME for 30 min while exposed to 12% and 15% O 2 ), and two hypoxic exposures (resting for 30 min while exposed to 12% and 15% O 2 ). The results showed that 1 ) plasma complement-C3a desArg/C4a desArg/C5a concentrations were increased, 2 ) expressions of L-selectin/lymphocyte functin-associated antigen-1/Mac-1/C5aR on neutrophils were enhanced, 3 ) phagocytosis of neutrophils to Esherichia coli and release of neutrophil oxidant products by E. coli were elevated, and 4 ) E. coli -induced phosphotidylserine exposure or caspase-3 activation of neutrophils were promoted immediately and 2 h after both 12% O 2 exposure at rest and with ME as well as normoxic SE. Although neither normoxic ME nor breathing 15% O 2 at rest influenced these complement- and neutrophil-related immune responses, ME at both 12% and 15% O 2 resulted in enhanced complement activation in the blood, expressions of opsonic/complement receptors on neutrophils, or the bactericidal activity and apoptosis of neutrophils. Moreover, the increased neutrophil oxidant production and apoptosis by normoxic SE and hypoxic ME were ameliorated by treating neutrophils with diphenylene iodonium (a NADPH oxidase inhibitor). Therefore, we conclude that ME at 12–15% O 2 enhances bactericidal capacity and facilitates the subsequent apoptosis of neutrophils.
phagocytosis; apoptosis
Address for reprint requests and other correspondence: J.-S. Wang, Graduate Institute of Rehabilitation Science, Chang Gung Univ., 259 Wen-Hwa 1st Rd., Kwei-Shan, Tao-Yuan 333, Taiwan (e-mail: s5492{at}mail.cgu.edu.tw ).
Background
Saussurea involucrata
(Kar. et Kir.) commonly known as ‘snow lotus’ or ‘Xue Lian’ is an important plant in the traditional Chinese system of medicine. The plant contains flavonoids such as ...syringin and rutin. These compounds have been reported to be anti-rheumatic, anti-inflammatory and dilate blood vessels, lower blood pressure, prevent cardiovascular diseases, enhance immunity, and act as anti-aging, anti-cancer, and anti-fatigue agents. The species has become endangered due to the excessive collection of
S. involucrata
plants in the wild, slower plant growth and ecological destruction of natural habitats. There is a severe shortage of plant material, while the market demand is ever increasing. Hence, it is very important to apply tissue culture technique for plant propagation and production of the bioactive compounds of this species.
Results
Multiple shoot induction and proliferation in shoot base explants derived from
in vitro
raised seedlings of
S. involucrata
was achieved on 3/4 strength of Murashige and Skoog’s (MS) basal medium (MSBM) supplemented with 1.0 mg/L
−1
BA and 1.5 mg/L
−1
NAA. Rooting was induced in 100 % shoots cultured on 1/2X MSBM supplemented with 1.0 mg/L
−1
IBA for one week and then transfer to auxin free medium. The plantlets could be acclimatized successfully by sachet technique and established in the greenhouse. Maximum callus induction and proliferation in leaf segments was achieved on 1/2X MSBM supplemented with 0.5 mg/L
−1
BA, 0.5 mg/L
−1
NAA, 0.4 % gelrite and on incubation at 20 °C. Container closures had an influence on the quality and quantity of callus and production of the active compounds. The HPLC analysis showed much higher syringin content in
in vitro
shoots and callus as compared to commercially available market crude drug.
Conclusion
The present study describes an
in vitro
culture protocol of
Saussurea involucrata.
The bioactive compounds, syringin and rutin could be produced through tissue culture technique without sacrificing the endangered
Saussurea involucrata
plants in the wild.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
碩士
國立高雄第一科技大學
行銷與流通管理研究所
100
Based on the viewpoints of consumer heuristics, we intent to explore the effectiveness of convenience goods’ certification information appeals and message presentation ...styles on perceived quality, whether will make “Guarantee of quality is best and pattern rather than word” or not. And under the more rigorous and scientific consideration, we adopted the scenario in our experimental design. In order to avoid the interference coming from other external factors, two factors mixed design were used, and conducted as 2 (certification information appeals: country-of-origin and quality) ×3 (message presentation styles: word, pattern and word combine pattern ). There are 102 subjects to attend the experiment, and each scenario 33 subjects.
Confirmed our research hypotheses, the interaction effect of certification information appeals and message presentation styles on perceived quality is significant, the result of simple main effect shows that the higher perceived quality in quality appeal
碩士
國立虎尾科技大學
工業工程與管理研究所
100
Malignancy has been the first of the ten leading causes of death in Taiwan. The death toll caused by malignancy in Yunlin County is the second highest among all the cities ...and counties and the malignancy death rate per 100,000 populations in Yunlin County is 1.5 times of the national mortality. Because of this, case hospital in this research has invested tremendous capital for purchasing medical equipments and physician resources in order to establish the environment of cancer treatment and care in Yunlin County. However, it is found that when the cancer have been diagnosed for the patients in Yunlin county they often go to other hospitals in the neighboring county or city and treated there but not stay and treated in the case hospital. Therefore, the cancer patient’s hospitalized ratio has been low for the case hospital.
In this study, the Analytic Hierarchy Process (AHP) is used to identify the key factor of selecting treatment hospital for the malignancy patients. Hopefully, thes
碩士
朝陽科技大學
生化科技研究所碩士班
99
Saussurea involucrate is one of the most important medicinal plants in China. This species is mainly distributed to snowy mountains at an altitude of 4000–5000 m. It has used ...in the Chinese system of traditional medicine for over 2000 years for the treatment of many diseases such as arthritis, cancer, lumbago, hypertension and gynecological disease. Over exploitation and ecological destruction of the natural habits in recent years leads to severe shortage of this species. While the market demands are ever increasing. The potential of micropropagation can be exploited for rapid multiplication of this plant species and it may be an important venue to meet the ever increasing demand. The isolation of active constituents from the wild plant is economically not viable. Thus, the use of plant tissue and cell culture methods can be an effective means to grow the plants at large scale and meet up the ever increasing demand. The present study describes the use of Response Surface Methodology (R
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