ABSTRACT
The transmission of coronavirus disease 2019 (COVID-19) has presented challenges for the control of the indoor environment of isolation wards. Scientific air distribution design and operation management are crucial to ensure the environmental safety of medical staff. This paper proposes the application of adaptive wall-based attachment ventilation and evaluates this air supply mode based on contaminants dispersion, removal efficiency, thermal comfort, and operating expense. Adaptive wall-based attachment ventilation provides a direct supply of fresh air to the occupied zone. In comparison with a ceiling air supply or upper sidewall air supply, adaptive wall-based attachment ventilation results in a 15%-47% lower average concentration of contaminants, for a continual release of contaminants at the same air changes per hour (ACH; 10 h-1). The contaminant removal efficiency of complete mixing ventilation cannot exceed 1. For adaptive wall-based attachment ventilation, the contaminant removal efficiency is an exponential function of the ACH. Compared with the ceiling air supply mode or upper sidewall air supply mode, adaptive wall-based attachment ventilation achieves a similar thermal comfort level (predicted mean vote (PMV) of -0.1-0.4; draught rate of 2.5%-6.7%) and a similar performance in removing contaminants, but has a lower ACH and uses less energy.
ABSTRACT
Objective To study the chemical constituents from the leaves of Cyclocarya paliurus. Methods The compounds were isolated and purified by chromatographic techniques and their structures were identified on the basis of spectral features. Results Forteen known compounds, including 11 flavonoids and three phenolic acids, named kaempferol (1), quercetin (2), apigenin (3), tricin (4), eupatilin (5), 3,7,8,3'-tetrahydroxy-4'-methoxyflavone (6), myricetin (7), 3,5-dihydroxy-7-methoxy-3',4'-methylenedioxyflavone (8), isoquercitrin (9), quercetin-3-O-β-D-glucuronide (10), myricetin-3-O-β-D-glucuronide (11), caffeic acid (12), 5-caffeoylquinic acid (13), and 3-hydroxybenzoic acid-4-O-β-D-glucopyranoside (14) were isolated from the leaves of C. paliurus. Conclusion Compounds 3, 4, 5, and 14 are firstly obtained from C. paliurus. Compounds 6 and 8 are isolated from the genus of Cyclocarya for the first time. Compounds 1-11 showed moderate active against the brine shrimp larvae, and compounds 12-14 indicated significant growth inhibitory activity against the brine shrimp (Artemia salina) larvae.
ABSTRACT
Five iridium bis(carbene) complexes, [Ir(pmi)(2)(pypz)] (1), [Ir(mpmi)(2)(pypz)] (2), [Ir(fpmi)(2)(pypz)] (3), [Ir(fpmi)(2)(pyim)] (4), and [Ir(fpmi)(2)(tfpypz)] (5) (pmi=1-phenyl-3-methylimdazolin-2-ylidene-C,C(2'); fpmi=1-(4-fluorophenyl)-3-methylimdazolin-2-ylidene-C,C(2'); mpmi=1-(4-methyl-phenyl)-3-methylimdazolin-2-ylidene-C,C(2'); pypz=2-(1H-pyrazol-5-yl)pyridinato; pyim=2-(1H-imidazol-2-yl)pyridinato; and tfpypz=2-(3-(trifluoromethyl)-1H-pyrazol-5-yl)pyridinato), were synthesized and their structures were characterized by NMR spectroscopy, mass spectroscopy and X-ray diffraction. These complexes showed phosphorescent emission with the emission maxima between 453 and 490 nm. Various spectrophotometric measurements, cyclic voltammetric studies, and density functional theory (DFT) calculations show that, unlike most of the phosphorescent cyclometalated iridium complexes, the lowest unoccupied molecular orbital (LUMO) energy and the emissive state of these iridium complexes are mainly controlled by the N,N'-heteroaromatic (N^N) ligand. Despite the fact that the LUMO levels of these complexes are mainly on the N^N ligands, the efficiencies of the electroluminescent (EL) devices are very high. For example, the EL devices using [Ir(mpmi)(2)(pypz)], [Ir(fpmi)(2)(pypz)], and [Ir(fpmi)(2)(tfpypz)] as the dopant emitters exhibited light- to deep-blue electrophosphorescence with external quantum efficiencies of 15.2, 14.1, and 7.6% and Commission Internationale d'Énclairage (x,y) coordinates (CIE(x,y)) of (0.14, 0.27), (0.14, 0.18) and (0.14, 0.10), respectively.
ABSTRACT
<p><b>OBJECTIVE</b>To evaluate prospectively the efficacy and clinical significance of ultrasonography (US), helical computed tomography (HCT), endoscopic ultrasonography (EUS) and magnetic resonance imaging (MRI) in assessing locoregional invasion to the surrounding tissue or organs of primary pancreatic carcinoma.</p><p><b>METHODS</b>Sixty-eight consecutive patients with pancreatic carcinoma underwent US, HCT, EUS and MRI examinations before surgical exploration. All imaging results in terms of tumor size and locoregional invasion were assessed separately by two diagnostic radiologists and compared with the surgical and pathological findings.</p><p><b>RESULTS</b>Among the HCT, US, EUS and MRI examinations, EUS had the highest accuracy in assessing tumor size with a regression coefficient for the maximal and minimal diameter of 1.0250 (P = 0.0426) and 0.9873 (P < 0.0001), respectively. In the assessment of locoregional invasion to the surrounding tissue or organs, EUS also had the highest accuracy (75.8%) and sensitivity (80.0%), but MRI had the highest positive predicting value (97.4%). None of these four imaging techniques was significantly correlated with the surgical findings when analyzed by univariate logistic regression.</p><p><b>CONCLUSION</b>Endoscopic ultrasonography may be the most useful imaging technique in assessing tumor size, but for assessing loco-regional invasion of primary pancreatic carcinoma, combination of more than one imaging techniques may be necessary.</p>
