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In this paper we argue for a developmental perspective in language assessment of second language learning, and that there is a need for an assessment with clear and precise criteria for evaluating the grammatical levels. Processability Theory is suggested as a theoretical framework for a stage model that enables teachers to follow the second language development over time. We have tested this appr

Advances in Inkjet-Printed Metal Halide Perovskite Photovoltaic and Optoelectronic Devices

Inkjet printing (IJP) has evolved over the past 30 years into a reliable, versatile, and cost-effective industrial production technology in many areas from graphics to printed electronic applications. Intensive research efforts have led to the successful development of functional electronic inks to realize printed circuit boards, sensors, lighting, actuators, energy storage, and power generation d

Cs x FA1- xPb(I1- yBr y)3 Perovskite Compositions : The Appearance of Wrinkled Morphology and its Impact on Solar Cell Performance

We report on the formation of wrinkle-patterned surface morphologies in cesium formamidinium-based CsxFA1-xPb(I1-yBry)3 perovskite compositions with x = 0-0.3 and y = 0-0.3 under various spin-coating conditions. By varying the Cs and Br contents, the perovskite precursor solution concentration and the spin-coating procedure, the occurrence and characteristics of the wrinkle-shaped morphology can b

Diffusion length of photo-generated charge carriers in layers and powders of CH3NH3PbI3 perovskite

The diffusion or transport lengths of photo-generated charge carriers in CH3NH3PbI3 layers (thickness up to 1 μm) and powders have been directly measured with high accuracy by modulated surface photovoltage after Goodman. The values of the diffusion lengths of photo-generated charge carriers ranged from 200 nm to tenths of μm. In thin CH3NH3PbI3 layers, the transport lengths corresponded to the la

Transient response of organo-metal-halide solar cells analyzed by time-resolved current-voltage measurements

The determination of the power conversion efficiency of solar cells based on organo-metal-halides is subject to an ongoing debate. As solar cell devices may exhibit very slow transient response, current-voltage scans in different directions may not be congruent, which is an effect often referred to as hysteresis. We here discuss time-resolved current-voltage measurements as a means to evaluate app

Hole transporting dye as light harvesting antenna in dye-sensitized TiO2 hybrid solar cells

We herein demonstrate the viability of utilizing the hole transporting medium of solidstate dye-sensitized solar cells for light harvesting. When using a hole transporting dye (HTD) in addition to an interface dye (ID) bound to the surface of the mesoporous metal oxide scaffold, both are shown to contribute to the photocurrent. Efficient energy transfer (ET) from the HTD to the ID was accomplished

Semi-transparent perovskite solar cells for tandems with silicon and CIGS

A promising approach for upgrading the performance of an established low-bandgap solar technology without adding much cost is to deposit a high bandgap polycrystalline semiconductor on top to make a tandem solar cell. We use a transparent silver nanowire electrode on perovskite solar cells to achieve a semi-transparent device. We place the semi-transparent cell in a mechanically-stacked tandem con

Chloride in lead chloride-derived organo-metal halides for perovskite-absorber solar cells

Organo-metal halide perovskites are an intriguing class of materials that have recently been explored for their potential in solar energy conversion. Within a very short period of intensive research, highly efficient solar cell devices have been demonstrated. One of the heavily debated questions in this new field of research concerns the role of chlorine in solution-processed samples utilizing lea

Hysteresis and transient behavior in current-voltage measurements of hybrid-perovskite absorber solar cells

Hybrid organo-metal halide perovskites are an exciting new class of solar absorber materials and have exhibited a rapid increase in solar cell efficiencies throughout the past two years to over 17% in both meso-structured and thin-film device architectures. We observe slow transient effects causing hysteresis in the current-voltage characterization of these devices that can lead to an over- or und

The treatment of renal hyperparathyroidism

Renal hyperparathyroidism (rHPT) is a complex and challenging disorder. It develops early in the course of renal failure and is associated with increased risks of fractures, cardiovascular disease and death. It is treated medically, but when medical therapy cannot control the hyperparathyroidism, surgical parathyroidectomy is an option. In this review, we summarize the pathophysiology, diagnosis,

Filter function of graphene oxide : Trapping perfluorinated molecules

We need clean drinking water, but current water purification methods are not always sufficient. This study examines the binding and binding mechanisms when graphene oxide is used as a filter material for removing perfluorinated substances and trihalomethanes. We use density functional theory calculations to examine the binding of the harmful molecules on graphene oxide. Our results indicate that t

The Mycobacterium marinum ESX-1 system mediates phagosomal permeabilization and type I interferon production via separable mechanisms

Following mycobacterial entry into macrophages the ESX-1 type VII secretion system promotes phagosomal permeabilization and type I IFN production, key features of tuberculosis pathogenesis. The current model states that the secreted substrate ESAT-6 is required for membrane permeabilization and that a subsequent passive leakage of extracellular bacterial DNA into the host cell cytosol is sensed by

Coherence and probability in legal evidence

The authors investigate to what extent an evaluation of legal evidence in terms of coherence (suggested by Thagard, Amaya, Van Koppen and others) is reconcilable with a probabilistic (Bayesian) approach to legal evidence. The article is written by one author (Dahlman) with a background in the bayesian approach to legal evidence, and one author (Mackor) with a background in scenario theory. The autThe authors investigate to what extent an evaluation of legal evidence in terms of coherence (suggested by Thagard, Amaya, Van Koppen and others) is reconcilable with a probabilistic (Bayesian) approach to legal evidence. The article is written by one author (Dahlman) with a background in the bayesian approach to legal evidence, and one author (Mackor) with a background in scenario theory. The aut

Cross-cutting view of current challenges in paediatric solid organ and haematopoietic stem cell transplantation in Europe : The European Reference Network TransplantChild

The low prevalence of European paediatric transplanted patients and scarcity of resources and expertise led to the need for a multidisciplinary network able to improve the quality of life of paediatric patients and families requiring a solid organ or haematopoietic stem cell transplantation. The European Reference Network (ERN) TransplantChild is one of the 24 ERNs established in a European legal