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71.
Cu2ZnSn(S,Se)4 (CZTSSe) solar cells with low cost and eco-friendly characteristics are attractive as future sources of electricity generation, but low conversion efficiency remains an issue. To improve conversion efficiency, a method of inserting intermediate layers between the CZTSSe absorber film and the Mo back contact is used to suppress the formation of MoSe2 and decomposition of CZTSSe. Among the candidates for the intermediate layer, graphene oxide (GO) and reduced GO have excellent properties, including high-charge mobility and low processing cost. Depending on the type of GO, the solar cell parameters, such as fill factor (FF), were enhanced. Thus, the conversion efficiency of 6.3% was achieved using the chemically reduced GO intermediate layer with significantly improved FF. 相似文献
72.
《Ophthalmology》1987,94(10):1310-1314
The adherence of Pseudomonas aeruginosa to extended-wear soft contact lenses (EWSCLs) may be an important initial step in the pathogenesis of EWSCL-associated infectious keratitis. P. aeruginosa tend to adhere more to worn EWSCLs than unworn EWSCLs (P < 0.05). Normal tear components such as aqueous solutions of albumin, lysozyme, and lactoferrin all significantly enhance adherence of P. aeruginosa to unworn EWSCLs often by as much as 300%. The presence of a 1 % solution of sialic acid in the bathing medium significantly reduces the adherence of P. aeruginosa to both unworn and worn lenses. Inhibition of bacterial adherence could also be achieved with the addition of mucin (which contains terminal sialic acid residues in its major sugar chains). Therefore, selective adherence by P. aeruginosa to a specific sugar (sialic acid) may be important in the initial attachment of the bacterium to soft contact lenses. 相似文献
73.
目的:评估有晶状体眼后房型人工晶状体(ICL)矫正超高度近视的疗效及安全性。方法:对超高度近视患者20例40眼接受普通型ICL或散光型后房型人工晶状体(TICL)治疗,术前屈光度球镜-10.0~-18.0D,柱镜-0.25~-3.00D,等效球镜-15.32D,术后随访12mo,观察指标包括UCVA,BCVA、角膜地形图、主观和客观验光、角膜内皮细胞计数、眼压测量、裂隙灯检查。结果:术后12mo,裸眼视力≥0.8者占80.0%(32眼)。30.0%(12眼)的术眼BCVA较术前提高1行,15.0%(6眼)的术眼BCVA较术前提高2行。术后12mo术眼屈光度在±0.50D者达70.0%(28眼)。术前患者平均眼压为16±2.8mmHg,术后6mo平均眼压为17±3.4mmHg,术前术后相比较差异无显著性(t=0.518,P=0.776),术前患者角膜内皮细胞计数平均为2823±243.6个/mm2,术后6mo平均为2709±273.2个/mm2,术前术后比较无显著性差异(t=0.794,P=0.422)。未发生继发性青光眼、视网膜脱离及并发性白内障。结论:ICL植入术矫正超高度近视具有良好的疗效和安全性,远期效果有待进一步观察。 相似文献
74.
角膜浅基质层针刺术联合软性角膜接触镜治疗丝状角膜炎临床观察 总被引:1,自引:0,他引:1
目的探讨角膜浅基质层针刺术联合软性角膜接触镜治疗丝状角膜炎的安全性和有效性。方法选择25例丝状角膜炎患者,表麻后刮除丝状物,间距0.5ram密集针刺病灶3ram范围内上皮层至浅基质层,术毕佩戴软性角膜接触镜,眼水点眼治疗原发病,随访观察。结果25例患者中21例症状完全消失,一次性治愈率84%,有效率100%。结论角膜浅基质层针刺联合软性角膜接触镜治疗丝状角膜炎是一种安全有效的方法,具有临床实用价值。 相似文献
75.
Energy harvesting devices made of piezoelectric material are highly anticipated energy sources for power wireless sensors. Tremendous efforts have been made to improve the performance of piezoelectric energy harvesters (PEHs). Noticeably, topology optimization has shown an attractive potential to design PEHs with enhanced energy conversion efficiency. In this work, an alternative yet more practical design objective was considered, where the open-circuit voltage of PEHs is enhanced by topologically optimizing the through-thickness piezoelectric material distribution of plate-type PEHs subjected to harmonic excitations. Compared to the conventional efficiency-enhanced designs, the open-circuit voltage of PEHs can be evidently enhanced by the proposed method while with negligible sacrifice on the energy conversion efficiency. Numerical investigations show that the voltage cancellation effect due to inconsistent voltage phases can be effectively ameliorated by optimally distributed piezoelectric materials. 相似文献
76.
Koichi Ito Emiko Chiba Noriko Oyama-Manabe Satoshi Washino Osamu Manabe Tomoaki Miyagawa Kohei Hamamoto Masahiro Hiruta Keisuke Tanno Hiroshi Shinmoto 《Magnetic resonance in medical sciences》2022,21(3):477
Purpose: To assess the diagnostic performance of the tumor contact length (TCL) and apparent diffusion coefficient (ADC) for predicting extraprostatic extension (EPE) of prostate cancer with capsular abutment (CA).Methods: Ninety-three patients with biopsy-proven prostate cancer underwent 3-Tesla MRI, including diffusion-weighted imaging (b value = 0, 2000 s/mm2) and radical prostatectomy. Two experienced radiologists, blinded to the clinicopathological data, retrospectively assessed the presence of CA on T2-weighted imaging (T2WI). TCL on T2WI and ADC values were measured on detecting CA in prostate cancer. We used the receiver operating characteristic curves to assess the diagnostic performance of TCL and ADC values for predicting EPE.Results: CA was present in 58 prostate cancers among 93 patients. The cut-off value for TCL was 6.9 mm, which yielded an area under the curve (AUC) of 0.75. This corresponded to a sensitivity, specificity, and accuracy of 84.2%, 61.5%, and 69.0%, respectively. The cut-off value for ADC was 0.63 × 10–3 mm2/s, which yielded an AUC of 0.76. This, in turn, corresponded to a sensitivity, specificity, and accuracy of 84.2%, 59.0%, and 67.2%, respectively. The combined cut-off value of TCL and ADC yielded an AUC of 0.82. The specificity (84.6%) and accuracy (81.0%) of the combined value were superior to their individual values (P < 0.05).Conclusion: A combination of TCL and ADC values provided high specificity and accuracy for detecting EPE of prostatic cancer with CA. 相似文献
77.
78.
Judy Strickland Qingda Zang Nicole Kleinstreuer Michael Paris David M. Lehmann Neepa Choksi Joanna Matheson Abigail Jacobs Anna Lowit David Allen Warren Casey 《Journal of applied toxicology : JAT》2016,36(9):1150-1162
One of the top priorities of the Interagency Coordinating Committee for the Validation of Alternative Methods (ICCVAM) is the identification and evaluation of non‐animal alternatives for skin sensitization testing. Although skin sensitization is a complex process, the key biological events of the process have been well characterized in an adverse outcome pathway (AOP) proposed by the Organisation for Economic Co‐operation and Development (OECD). Accordingly, ICCVAM is working to develop integrated decision strategies based on the AOP using in vitro, in chemico and in silico information. Data were compiled for 120 substances tested in the murine local lymph node assay (LLNA), direct peptide reactivity assay (DPRA), human cell line activation test (h‐CLAT) and KeratinoSens assay. Data for six physicochemical properties, which may affect skin penetration, were also collected, and skin sensitization read‐across predictions were performed using OECD QSAR Toolbox. All data were combined into a variety of potential integrated decision strategies to predict LLNA outcomes using a training set of 94 substances and an external test set of 26 substances. Fifty‐four models were built using multiple combinations of machine learning approaches and predictor variables. The seven models with the highest accuracy (89–96% for the test set and 96–99% for the training set) for predicting LLNA outcomes used a support vector machine (SVM) approach with different combinations of predictor variables. The performance statistics of the SVM models were higher than any of the non‐animal tests alone and higher than simple test battery approaches using these methods. These data suggest that computational approaches are promising tools to effectively integrate data sources to identify potential skin sensitizers without animal testing. Published 2016. This article has been contributed to by US Government employees and their work is in the public domain in the USA. 相似文献
79.
Comfort-Kone硬性角膜接触镜矫治圆锥角膜 总被引:1,自引:0,他引:1
目的观察comfort-kone硬性角膜接触镜(rigid gas-permeable contact lens,RGPCL)控制圆锥角膜发展的效果。方法 52例(94眼)患者采用"三点接触法"配戴comfort-kone RGPCL,分析对比配戴后屈光度、角膜地形图参数及泪液情况的变化,评价RGPCL控制圆锥角膜发展的临床效果。结果配戴RGPCL后最佳矫正视力0.83±0.24,与配戴前最佳矫正视力0.58±0.35比较,差异有显著统计学意义(t=-8.87,P=0.00);RGPCL矫正视力与配戴眼屈光度和角膜曲率半径呈显著相关(P=0.001、0.000),与角膜散光度无显著相关性(P=0.081)。随访期间RGPCL矫正视力稳定,角膜健康状况良好;患者主观适应时间为(11.13±9.10)d;长期配戴后基础泪液分泌量显著降低,差异有显著统计学意义(t=2.867,P=0.007)。结论 Comfort-Kone RGPCL能够显著提高圆锥角膜患者的视觉质量,长时间配戴安全、稳定,有效地控制了圆锥角膜的持续发展。 相似文献
80.
Smith J Plaat F Fisk NM 《BJOG : an international journal of obstetrics and gynaecology》2008,115(8):1037-1042
Although much effort has gone into promoting early skin-to-skin contact and parental involvement at vaginal birth, caesarean birth remains entrenched in surgical and resuscitative rituals, which delay parental contact, impair maternal satisfaction and reduce breastfeeding. We describe a 'natural' approach that mimics the situation at vaginal birth by allowing (i) the parents to watch the birth of their child as active participants (ii) slow delivery with physiological autoresuscitation and (iii) the baby to be transferred directly onto the mother's chest for early skin-to-skin. Studies are required into methods of reforming caesarean section, the most common operation worldwide. 相似文献