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111.
Andrej Classen Lukas Einsiedler Thomas Heumueller Arko Graf Maximilian Brohmann Felix Berger Simon Kahmann Moses Richter Gebhard J. Matt Karen Forberich Jana Zaumseil Christoph J. Brabec 《Liver Transplantation》2019,9(1)
Current state‐of‐the‐art organic solar cells (OSCs) still suffer from high losses of open‐circuit voltage (VOC). Conventional polymer:fullerene solar cells usually exhibit bandgap to VOC losses greater than 0.8 V. Here a detailed investigation of VOC is presented for solution‐processed OSCs based on (6,5) single‐walled carbon nanotube (SWCNT): [6,6]‐phenyl‐C71‐butyric acid methyl ester active layers. Considering the very small optical bandgap of only 1.22 eV of (6,5) SWCNTs, a high VOC of 0.59 V leading to a low Egap/q ? VOC = 0.63 V loss is observed. The low voltage losses are partly due to the lack of a measurable charge transfer state and partly due to the narrow absorption edge of SWCNTs. Consequently, VOC losses attributed to a broadening of the band edge are very small, resulting in VOC,SQ ? VOC,rad = 0.12 V. Interestingly, this loss is mainly caused by minor amounts of SWCNTs with smaller bandgaps as well as (6,5) SWCNT trions, all of which are experimentally well resolved employing Fourier transform photocurrent spectroscopy. In addition, the low losses due to band edge broadening, a very low voltage loss are also found due to nonradiative recombination, ΔVOC,nonrad = 0.26 V, which is exceptional for fullerene‐based OSCs. 相似文献
112.
Andrej Classen Thomas Heumueller Isabell Wabra Johannes Gerner Yakun He Lukas Einsiedler Ning Li Gebhard J. Matt Andres Osvet Xiaoyan Du Andreas Hirsch Christoph J. Brabec 《Liver Transplantation》2019,9(39)
With state‐of‐the‐art organic solar cells (OSCs) surpassing 16% efficiency, stability becomes critical for commercialization. In this work, the power of using photoluminescence (PL) measurements on plain films is demonstrated, as well as high‐performance liquid chromatography analysis to reveal the origin of UV instabilities in OSCs based on the most commonly used acceptors PC70BM ([6,6]‐phenyl‐C71‐butyric acid methyl ester), ITIC (3,9‐bis(2‐methylene‐(3‐(1,1‐dicyanomethylene)‐indanone))‐5,5,11,11‐tetrakis(4‐hexylphenyl)‐dithieno[2,3‐d:2′,3′‐d′]‐s‐indaceno[1,2‐b:5,6‐b′]dithiophene), and o‐IDTBR (indacenodithiophene‐based non‐fullerene acceptor). The UV dependent stability tests reveal instabilities in solar cells based on PC70BM and ITIC while devices based on o‐IDTBR are highly stable even under UV illumination. The analysis of solar cell devices based on charge extraction and sub‐bandgap external quantum efficiency only shows the UV‐dependent emergence of traps, while PL spectra of plain films on glass allows the disentanglement and identification of individual instabilities in multi‐component bulk‐heterojunction devices. In particular, the PL analysis demonstrates UV instabilities of PC70BM and ITIC toward the processing additive 1,8 diiodooctane (DIO). The chemical analysis reveals the in‐depth mechanism, by providing direct proof of photochemical reactions of PC70BM and ITIC with UV‐induced radicals of DIO. Based on this scientific understanding, it is shown how to stabilize PBQ‐QF:PC70BM devices. 相似文献
113.
Prolonged response times are observed with targets having been presented as distractors immediately before, called negative priming effect. Among others, inhibitory and retrieval processes have been suggested underlying this behavioral effect. As those processes would involve different neural activation patterns, a functional magnetic resonance imaging (fMRI) study including 28 subjects was conducted. Two tasks were used to investigate stimulus repetition effects. One task focused on target location, the other on target identity. Both tasks are known to elicit the expected response time effects. However, there is less agreement about the relationship of those tasks with the explanatory accounts under consideration. Based on within-subject comparisons we found clear differences between the experimental repetition conditions and the neutral control condition on neural level for both tasks. Hemodynamic fronto-striatal activation patterns occurred for the location-based task favoring the selective inhibition account. Hippocampal activation found for the identity-based task suggests an assignment to the retrieval account; however, this task lacked a behavioral effect. 相似文献
114.
Tobias Stubhan Ning Li Norman A. Luechinger Samuel C. Halim Gebhard J. Matt Christoph J. Brabec 《Liver Transplantation》2012,2(12):1433-1438
We demonstrate solution‐processed tungsten trioxide (WO3) incorporated as hole extraction layer (HEL) in polymer solar cells (PSCs) with active layers comprising either poly(3‐hexylthiophene) (P3HT) or poly[(4,4'‐bis(2‐ethylhexyl)dithieno[3,2‐b:2′,3′‐d]silole)‐2,6‐diyl‐alt‐(4,7‐bis(2‐thienyl)‐2,1,3‐benzothiadiazole)‐5,50‐diyl] (Si‐PCPDTBT) mixed with a fullerene derivative. The WO3 layers are deposited from an alcohol‐based, surfactant‐free nanoparticle solution. A short, low‐temperature (80 °C) annealing is sufficient to result in fully functional films without the need for an oxygen‐plasma treatment. This allows the application of the WO3 buffer layer in normal as well as inverted architecture solar cells. Normal architecture devices based on WO3 HELs show comparable performance to the PEDOT:PSS reference devices with slightly better fill factors and open circuit voltages. Very high shunt resistances (over 1 MΩ cm2) and excellent diode rectification underline the charge selectivity of the solution‐processed WO3 layers. 相似文献
115.
116.
Thoma G Beerli C Bigaud M Bruns C Cooke NG Streiff MB Zerwes HG 《Bioorganic & medicinal chemistry letters》2008,18(6):2000-2005
Introduction of polar groups in a series of potent CCR5 antagonists which are very likely to adversely affect the conduction system in the heart led to the identification of NIBR-1282 which did not show adverse effects when tested in an isolated rabbit heart ex vivo model. Administration of NIBR-1282 in combination with a non-efficacious dose of CsA led to significant prolongation of kidney allograft survival in cynomolgus monkeys. 相似文献
117.
Conrad H Gebhard K Krönig H Neudorfer J Busch DH Peschel C Bernhard H 《Journal of immunology (Baltimore, Md. : 1950)》2008,180(12):8135-8145
The human epidermal growth factor receptor 2 (HER2) has been targeted as a breast cancer-associated Ag by T cell-based immunotherapeutical strategies such as cancer vaccines and adoptive T cell transfer. The prerequisite for a successful T cell-based therapy is the induction of T cells capable of recognizing the HER2-expressing tumor cells. In this study, we generated human cytotoxic T cell clones directed against the HER2(369-377) epitope known to be naturally presented with HLA-A*0201. Those HER2-reactive CTLs, which were also tumor lytic, exhibited a similar lysis pattern dividing the targets in lysable and nonlysable tumor cells. Several HER2-expressing tumor cells became susceptible to CTL-mediated lysis after IFN-gamma treatment and, in parallel, up-regulated molecules of the Ag-presenting machinery, indicating that the tumor itself also contributes to the success of CTL-mediated killing. Some of the HER2(369-377)-reactive T cells specifically cross-reacted with the corresponding peptides derived from the family members HER3 and/or HER4 due to a high sequence homology. The epitopes HER3(356-364) and HER4(361-369) were endogenously processed and contributed to the susceptibility of cell lysis by HER cross-reacting CTLs. The principle of "double" or "triple targeting" the HER Ags by cross-reacting T cells will impact the further development of T cell-based therapies. 相似文献
118.
119.
Valentin Aebischer Amar Abu-Ghazaleh Gisela Metzler Lena Riedl Claus Garbe Lukas Flatz Thomas Eigentler Stephan Forchhammer 《Pigment cell & melanoma research》2023,36(6):512-521
The increasing number of melanoma patients makes it necessary to develop best possible strategies for prognosis assessment in order to recommend appropriate therapy and follow-up. The prognostic significance of tumor cell pigmentation has not been fully elucidated. Hematoxylin and eosin (H&E)-stained sections of 775 melanomas diagnosed between 2012 and 2015 were independently assessed for melanin pigment abundance by two investigators, and the impact on melanoma-specific survival was calculated. Unpigmented melanomas (n = 99) had a melanoma-specific survival of 67.7%, melanomas with moderate pigmentation (n = 384) had a melanoma-specific survival of 85.9%, and strongly pigmented melanomas (n = 292) had a melanoma-specific survival of 91.4% (p < .001). In an analysis of melanoma-specific survival adjusted for pT stage and pigmentation, we found a nonsignificant impact of pigmentation abundance with a hazard ratio of 1.277 (p = .74). The study presented here provides evidence in a German cohort that patients with pigmented melanomas have a more favorable prognosis than those diagnosed with nonpigmented melanomas. Moreover, the abundance of pigmentation already seems to provide a first prognostic estimate. However, it does not appear to provide significant additional value for prognostic assessment according to the AJCC 2017 pT classification. 相似文献
120.
Molecularly cloned feline immunodeficiency virus NCSU1 JSY3 induces immunodeficiency in specific-pathogen-free cats. 总被引:3,自引:0,他引:3
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J S Yang R V English J W Ritchey M G Davidson T Wasmoen J K Levy D H Gebhard M B Tompkins W A Tompkins 《Journal of virology》1996,70(5):3011-3017
A full-length feline immunodeficiency virus NCSU1 (FIV-NCSU1) genome (JSY3) was cloned directly from FIV-NCSU1-infected feline CD4+ lymphocyte (FCD4E) genomic DNA and identified by PCR amplification with 5' long terminal repeat, gag, env, and 3' long terminal repeat primer sets. Supernatant from FCD4E cells cocultured with JSY3-transfected Crandell feline kidney (CrFK) cells was used as an inoculum. Cell-free JSY3 virus was cytopathogenic for FCD4E lymphocytes but did not infect CrFK cells in vitro. To determine in vivo infectivity and pathogenesis, six young adult specific-pathogen-free cats were inoculated with cell-free JSY3 virus. Provirus was detected at 2 weeks postinfection (p.i.) and was still detectable at 25 weeks p.i. as determined by gag region PCR-Southern blot analysis of peripheral blood mononuclear cell lysates. Infectious virus was recovered from peripheral blood mononuclear cells at 6 and 25 weeks p.i., and an antibody response to FIV was detected by 4 weeks. In the acute phase of infection, JSY3 provirus was found only in the CD4+ lymphocyte subset; however, by 14 weeks p.i., the greatest provirus burden was detected in B lymphocytes. All six cats were panlymphopenic at 2 weeks p.i., CD4+/CD8+ ratios were inverted by 6 weeks p.i., and five of the six cats developed lymphadenopathy by 10 weeks p.i. To determine if the JSY3 molecular clone caused immunodeficiency similar to that of the parental wild-type FIV-NCSU1, the cats were challenged with the low-virulence ME49 strain of Toxoplasma gondii at 29 weeks p.i. Five of six cats developed clinical signs consistent with generalized toxoplasmosis, and three of six cats developed acute respiratory distress and required euthanasia. Histopathologic examination of the severely affected cats revealed generalized inflammatory reactions and the presence of T. gondii tachyzoites in multiple tissues. None of the six age- and sex-matched specific-pathogen-free cats inoculated with only T. gondii developed clinical disease. Our results suggest that the pathogenesis of the molecularly cloned NCSU1 JSY3 is similar to that of wild-type FIV-NCSU1. 相似文献