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1.
ACS Appl Mater Interfaces ; 13(20): 24130-24137, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-33974398

RESUMO

Radiative cooling to subambient temperatures can be efficiently achieved through spectrally selective emission, which until now has only been realized by using complex nanoengineered structures. Here, a simple dip-coated planar polymer emitter derived from polysilazane, which exhibits strong selective emissivity in the atmospheric transparency window of 8-13 µm, is demonstrated. The 5 µm thin silicon oxycarbonitride coating has an emissivity of 0.86 in this spectral range because of alignment of the frequencies of bond vibrations arising from the polymer. Furthermore, atmospheric heat absorption is suppressed due to its low emissivity outside the atmospheric transparency window. The reported structure with the highly transparent polymer and underlying silver mirror reflects 97% of the incoming solar irradiation. A temperature reduction of 6.8 °C below ambient temperature was achieved by the structure under direct sunlight, yielding a cooling power of 93.7 W m-2. The structural simplicity, durability, easy applicability, and high selectivity make polysilazane a unique emitter for efficient prospective passive daytime radiative cooling structures.

2.
Nanoscale Res Lett ; 16(1): 50, 2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33744997

RESUMO

Oxide/metal/oxide (OMO) layer stacks are used to replace transparent conductive oxides as front contact of thin-film solar cells. These multilayer structures not only reduce the overall thickness of the contact, but can be used for colouring of the cells utilizing interference effects. However, sheet resistance and parasitic absorption, both of which depend heavily on the metal layer, should be further reduced to reach higher efficiencies in the solar cells. In this publication, AgOX wetting layers were applied to OMO electrodes to improve the performance of Cu(In,Ga)Se2 (CIGS) thin-film solar cells. We show that an AgOX wetting layer is an effective measure to increase transmission and conductivity of the multilayer electrode. With the presented approach, we were able to improve the short-circuit current density by 18% from 28.8 to 33.9 mA/cm2 with a metal (Ag) film thickness as low as 6 nm. Our results highlight that OMO electrodes can be an effective replacement for conventional transparent conductive oxides like aluminium-doped zinc oxide on thin-film solar cells.

3.
Diagnostics (Basel) ; 10(6)2020 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-32512707

RESUMO

Breast cancers (BC) can mutate, allowing metastatic tumors (MT) to sometimes differ to primary tumors (PT) in gene expression. Despite contemporary metastatic breast cancer (MBC) therapy, subtype conversion seems prognostically disadvantageous. We strived to determine the influence of mRNA-assessed intrinsic subtype stability comparing PT and MT biopsies and circulating tumor cell (CTC)-based liquid biopsies on progression free survival (PFS) and overall survival (OS). Additional analyzed prognostic factors were PT subtype, MT subtype and hormone receptor loss. Kaplan-Meier curves and the log rank tests were used to compare PFSs and OSs. The proportions of luminal B and triple negative subtype MTs were increased compared to those observed in PTs. Fifteen patients were found to have tumors that underwent intrinsic subtype conversion and their OS was significantly decreased (p = 0.038). No such difference was observed when it comes to PFS. The majority of these tumors switched to a more aggressive intrinsic subtype. No significant differences in PFSs or OSs were observed between subtype converters with triple negative PTs compared to those with luminal subtype PTs. The same is true of subtype stable patients. Total CTC, iCTC and aCTC counts decreased with therapy, but there were no significant differences between subtype converters and subtype stable patients. Our data confirm a poorer overall survival of the intrinsic subtype converters and emphasize the importance of acquiring biopsies and re-biopsies of all available metastatic lesions alongside with CTC-based liquid biopsies for earlier recognition of patients with poorer prognosis and in need of altered individualized therapy regimens.

4.
J Pain ; 20(8): 898-907, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30710707

RESUMO

Spatial integration of parts of the body is impaired in patients with complex regional pain syndrome (CRPS). Because the training of mental rotation (MR) has been shown to be among the effective therapy strategies for CRPS, impairment of MR is also important for the pathophysiological understanding of CRPS. The aim of this study was to evaluate whether differences in the neural representation of MR occur between patients with CRPS and healthy controls (HC). Therefore, we included 15 patients with chronic CRPS and 15 age- and gender-matched HC. We assessed behavioral (accuracy and reaction time for MR of both hands), clinical (Disabilities of Arm, Shoulder and Hand questionnaire) and magnetic resonance imaging (T1-weighted, function magnetic resonance imaging during MR) data. Reaction times in the patient group were delayed compared with HC without a lateralization effect for the affected hand side. Although both groups showed an activation pattern typical for MR, only HC showed a highly significant contrast for the rotated versus unrotated hands in the right intraparietal sulcus. Patients with CRPS showed a reduction of functional magnetic resonance imaging activation in areas including the subthalamic nucleus, nucleus accumbens, and putamen. Regression analysis for the CRPS group emphasized the importance of putamen and nucleus accumbens activation for MR performance. This study highlights the reduced access of patients with CRPS for mental resources modulating arousal, emotional response, and subcortical sensorimotor integration. PERSPECTIVE: This study localized the underlying neural responses for impaired mental rotation in patients with complex regional pain syndrome as a decrease in basal ganglia (putamen) and nucleus accumbens activation.


Assuntos
Encéfalo/diagnóstico por imagem , Síndromes da Dor Regional Complexa/diagnóstico por imagem , Imaginação/fisiologia , Rotação , Adulto , Idoso , Idoso de 80 Anos ou mais , Mapeamento Encefálico , Síndromes da Dor Regional Complexa/fisiopatologia , Feminino , Mãos/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tempo de Reação/fisiologia
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