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1.
Nature ; 604(7905): 280-286, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35418631

RESUMO

Multijunction solar cells can overcome the fundamental efficiency limits of single-junction devices. The bandgap tunability of metal halide perovskite solar cells renders them attractive for multijunction architectures1. Combinations with silicon and copper indium gallium selenide (CIGS), as well as all-perovskite tandem cells, have been reported2-5. Meanwhile, narrow-gap non-fullerene acceptors have unlocked skyrocketing efficiencies for organic solar cells6,7. Organic and perovskite semiconductors are an attractive combination, sharing similar processing technologies. Currently, perovskite-organic tandems show subpar efficiencies and are limited by the low open-circuit voltage (Voc) of wide-gap perovskite cells8 and losses introduced by the interconnect between the subcells9,10. Here we demonstrate perovskite-organic tandem cells with an efficiency of 24.0 per cent (certified 23.1 per cent) and a high Voc of 2.15 volts. Optimized charge extraction layers afford perovskite subcells with an outstanding combination of high Voc and fill factor. The organic subcells provide a high external quantum efficiency in the near-infrared and, in contrast to paradigmatic concerns about limited photostability of non-fullerene cells11, show an outstanding operational stability if excitons are predominantly generated on the non-fullerene acceptor, which is the case in our tandems. The subcells are connected by an ultrathin (approximately 1.5 nanometres) metal-like indium oxide layer with unprecedented low optical/electrical losses. This work sets a milestone for perovskite-organic tandems, which outperform the best p-i-n perovskite single junctions12 and are on a par with perovskite-CIGS and all-perovskite multijunctions13.


Assuntos
Compostos de Cálcio , Índio , Cobre , Óxidos , Titânio
2.
Int J Cardiovasc Imaging ; 37(8): 2501-2515, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34019206

RESUMO

To provide clinically relevant criteria for differentiation between the athlete's heart and similar appearing hypertrophic (HCM), dilated (DCM), and arrhythmogenic right-ventricular cardiomyopathy (ARVC) in MRI. 40 top-level athletes were prospectively examined with cardiac MR (CMR) in two university centres and compared to retrospectively recruited patients diagnosed with HCM (n = 14), ARVC (n = 18), and DCM (n = 48). Analysed MR imaging parameters in the whole study cohort included morphology, functional parameters and late gadolinium enhancement (LGE). Mean left-ventricular enddiastolic volume index (LVEDVI) was high in athletes (105 ml/m2) but significantly lower compared to DCM (132 ml/m2; p = 0.001). Mean LV ejection fraction (EF) was 61% in athletes, below normal in 7 (18%) athletes vs. EF 29% in DCM, below normal in 46 (96%) patients (p < 0.0001). Mean RV-EF was 54% in athletes vs. 60% in HCM, 46% in ARVC, and 41% in DCM (p < 0.0001). Mean interventricular myocardial thickness was 10 mm in athletes vs. 12 mm in HCM (p = 0.0005), 9 mm in ARVC, and 9 mm in DCM. LGE was present in 1 (5%) athlete, 8 (57%) HCM, 10 (56%) ARVC, and 21 (44%) DCM patients (p < 0.0001). Healthy athletes' hearts are characterized by both hypertrophy and dilation, low EF of both ventricles at rest, and increased interventricular septal thickness with a low prevalence of LGE. Differentiation of athlete's heart from other non-ischemic cardiomyopathies in MRI can be challenging due to a significant overlap of characteristics also seen in HCM, ARVC, and DCM.


Assuntos
Cardiomegalia Induzida por Exercícios , Cardiomiopatias , Cardiomiopatia Hipertrófica , Atletas , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Meios de Contraste , Gadolínio , Humanos , Hipertrofia Ventricular Esquerda , Imageamento por Ressonância Magnética , Valor Preditivo dos Testes , Estudos Retrospectivos
3.
Acta Oncol ; 59(2): 149-156, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31559880

RESUMO

Background: We evaluated efficacy and toxicity of 68Ga-PSMA-Positron Emission Tomography/Computed Tomography (PET/CT)-directed stereotactic body radiotherapy and image-guided radiotherapy (SBRT/IGRT) for oligometastases of prostate cancer recurrences after previous surgery.Methods: Nineteen patients were analyzed within a prospective PET-registry study (064/2013BO1) and retrospectively analyzed (807/2017BO2) fulfilling the following inclusion criteria: biochemical recurrence after radical prostatectomy, ≤five 68Ga-PSMA-PET/CT positive lesions. Biochemical control was evaluated with EORTC (European Organization for Research and Treatment of Cancer)- and Phenix-definitions. Toxicity was scored according to CTCAE-criteria v. 4.03.Results: A total of 38 oligometastases (19 patients, 2 with re-treatment) were treated with SBRT/IGRT from October 2014 to July 2017. 68Ga-PSMA-PET/CT-positive lesions were detected on average 39 months (5-139) after prostatectomy (pT2b-3b pN0-1 cM0). Mean PSA (Prostate-specific antigen)-level at time of imaging reached 2.2 ng/mL (range 0.2-10.1). PET/CT-positive lesions were treated with different fractionation schedules reaching biological equivalent doses (BED) of 116.7-230.0 Gy. Concomitant androgen deprivation therapy (ADT) was given in seven patients. After a median follow-up of 17 months (4-42) all patients were alive. Estimated 1-year PSA- control (n = 19) reached 80.8% (Phenix) and 67.5% (EORTC). A PSA-decline (≥50%) was detected in 16/19 patients after radiotherapy. Higher graded G3+-acute toxicity did not occur. Temporary late G3-proctitis was detected in one patient.Conclusions: Reaching of nadir ≤0.1 or 0.2 ng/mL was associated by improved DMFS (distant metastases free survival) and could serve as a surrogate endpoint for RT of oligometastases after initial prostatectomy. Short term effects of 68Ga-PSMA-PET/CT-based ablative radiotherapy for oligometastases demonstrated an acceptable toxicity profile and favorable biochemical response.


Assuntos
Neoplasias da Próstata/patologia , Neoplasias da Próstata/radioterapia , Idoso , Fracionamento da Dose de Radiação , Isótopos de Gálio , Radioisótopos de Gálio , Humanos , Masculino , Glicoproteínas de Membrana/uso terapêutico , Pessoa de Meia-Idade , Metástase Neoplásica , Compostos Organometálicos/uso terapêutico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Intervalo Livre de Progressão , Estudos Prospectivos , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/mortalidade , Radiocirurgia , Radioterapia Guiada por Imagem , Estudos Retrospectivos
4.
J Vestib Res ; 28(5-6): 401-407, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30856139

RESUMO

BACKGROUND: The video-head impulse test employs the vestibulo-ocular reflex (VOR) to assess vestibular function. To this day, no consensus has been reached among scientists in terms of whether or not vHIT results change in MD patients as the disease progresses. OBJECTIVE: To assess whether the vHIT is more often abnormal in later stages of MD compared to earlier stages. METHODS: We retrospectively analyzed patients with 'definite' MD who had undergone a vHIT and caloric test between 2012 and 2015. Patients were evaluated based on duration of disease in years (≤1, >1≤5, >5≤10, >10) and stage of disease (stage I and II versus III and IV). For the vHIT, an abnormal vestibulo-ocular reflex was defined as a gain cut-off value of≤0.8 and presence of correction saccades including subanalyses using a cut-off value of≤0.9. RESULTS: In 89 definite MD patients (42 (47%) male, mean age 55±5 (SD)), data on both the caloric test and the vHIT were available. The risk of an abnormal vHIT was 25% in patients with a duration of disease over 10 years compared to 22% in the patients with a disease duration of 10 years or less (risk difference 3%, 95% CI:- 28% to 35%), p = 0.82). The risk for an abnormal vHIT in the Stage I and Stage II was 17% compared to 26% in Stage III and IV (risk difference 9%, 95% CI:- 30% to 11%). When using a cut-off value of 0.9 we also did not demonstrate a relationship between the duration of disease and the proportion of abnormal vHIT test results. CONCLUSIONS: There is no relationship between the proportion of abnormal vHIT test results in patients with MD in either duration or stage of disease.


Assuntos
Teste do Impulso da Cabeça/métodos , Doença de Meniere/fisiopatologia , Canais Semicirculares/fisiopatologia , Vestíbulo do Labirinto/fisiopatologia , Testes Calóricos , Feminino , Humanos , Masculino , Doença de Meniere/classificação , Pessoa de Meia-Idade , Reflexo Vestíbulo-Ocular/fisiologia , Estudos Retrospectivos , Fatores de Tempo , Gravação em Vídeo
5.
Nat Commun ; 8: 13938, 2017 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-28067308

RESUMO

The area of thin-film photovoltaics has been overwhelmed by organometal halide perovskites. Unfortunately, serious stability concerns arise with perovskite solar cells. For example, methyl-ammonium lead iodide is known to decompose in the presence of water and, more severely, even under inert conditions at elevated temperatures. Here, we demonstrate inverted perovskite solar cells, in which the decomposition of the perovskite is significantly mitigated even at elevated temperatures. Specifically, we introduce a bilayered electron-extraction interlayer consisting of aluminium-doped zinc oxide and tin oxide. We evidence tin oxide grown by atomic layer deposition does form an outstandingly dense gas permeation barrier that effectively hinders the ingress of moisture towards the perovskite and-more importantly-it prevents the egress of decomposition products of the perovskite. Thereby, the overall decomposition of the perovskite is significantly suppressed, leading to an outstanding device stability.

6.
Parkinsonism Relat Disord ; 19(12): 1110-2, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23948517

RESUMO

BACKGROUND: Dizziness is a frequent complaint of patients with Parkinson's disease (PD), and orthostatic hypotension (OH) is often thought to be the cause. We studied whether benign paroxysmal positional vertigo (BPPV) could also be an explanation. AIM: To assess the prevalence of benign paroxysmal positional vertigo in patients with Parkinson's disease, with and without dizziness. METHODS: 305 consecutive outpatients with PD completed the Movement Disorders Society-sponsored revision of the Unified Parkinsons' Disease Rating Scale-motor score, the Dizziness Handicap Inventory, the Dix-Hallpike maneuver and a test for orthostatic hypotension. When positive for benign paroxysmal positional vertigo, a repositioning maneuver was performed. Patients were followed for three months to determine the clinical response. RESULTS: 305 patients responded (186 men (61%), mean age 70.5 years (Standard Deviation 9.5 years)), of whom 151 (49%) complained of dizziness. 57 (38%) of the dizzy patients appeared to have orthostatic hypotension; 12 patients (8%) had a classical but previously unrecognized benign paroxysmal positional vertigo. A further four patients (3%) had a more atypical presentation of benign paroxysmal positional vertigo. Three months after treatment, 11 (92%) of patients with classical benign paroxysmal positional vertigo were almost or completely without complaints. We found no 'hidden' benign paroxysmal positional vertigo among patients without dizziness. The prevalence of benign paroxysmal positional vertigo among all patients with PD was 5.3%. CONCLUSION: Among Parkinson patients with symptoms of dizziness, up to 11% may have benign paroxysmal positional vertigo, which can be treated easily and successfully.


Assuntos
Tontura/epidemiologia , Doença de Parkinson/complicações , Vertigem/epidemiologia , Idoso , Vertigem Posicional Paroxística Benigna , Tontura/etiologia , Feminino , Humanos , Masculino , Pacientes Ambulatoriais , Prevalência , Vertigem/etiologia
7.
Bone Marrow Transplant ; 46(1): 110-5, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20383220

RESUMO

Autologous SCT (auto-SCT) introduces a reduced tolerance to chemotherapy even in patients with adequate engraftment, suggesting long-term effects of the transplantation procedure on the BM capacity. To study the hematopoietic cell compartment after auto-SCT, CD34(+) BM cells (n = 16) from patients at 6-9 months after auto-SCT were studied with regard to the progenitor subsets, colony frequency and cell cycle status. The BM compartments were studied in vivo using PET tracer 3-fluoro-3-deoxy-L-thymidine (¹8F-FLT PET). BM CD34(+) cells after auto-SCT were compared with normal CD34(+) cells and showed a phenotypic shift from common myeloid progenitor (CMP mean percentage 3.7 vs 19.4%, P=0.001) to granulocyte-macrophage progenitor (GMP mean percentage 51.8 vs 27.6%, P=0.01). In addition, a reduced clonogenic potential and higher cycling activity especially of the GMP fraction (41% ± 4 in G2/S phase vs 19% ± 2, P = 0.03) were observed in BM after auto-SCT compared with normal. The enhanced cycling activity was confirmed in vivo by showing a significantly higher uptake of the ¹8F-FLT PET tracer by the BM compartment. This study shows that auto-SCT results in defects of the hematopoietic compartment at least 6 months after auto-SCT, characterized by changes in the composition of progenitor subsets and enhanced in vitro and in vivo cycling activity.


Assuntos
Ciclo Celular , Transplante de Células-Tronco Hematopoéticas , Imagem Molecular/métodos , Células Progenitoras Mieloides/metabolismo , Fenótipo , Adulto , Antígenos CD34/metabolismo , Medula Óssea/metabolismo , Ensaio de Unidades Formadoras de Colônias , Didesoxinucleosídeos/farmacocinética , Seguimentos , Células Progenitoras de Granulócitos e Macrófagos/citologia , Células Progenitoras de Granulócitos e Macrófagos/metabolismo , Humanos , Linfoma/terapia , Pessoa de Meia-Idade , Células Progenitoras Mieloides/citologia , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/farmacocinética , Distribuição Tecidual , Transplante Autólogo , Imagem Corporal Total
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