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Li-Doping and Ag-Alloying Interplay Shows the Pathway for Kesterite Solar Cells with Efficiency Over 14%
No full textKesterite photovoltaic technologies are critical for the deployment of light-harvesting devices in buildings and products, enabling energy sustainable buildings, and households. The recent improvements in kesterite power conversion efficiencies have focused on improving solution-based precursors by improving the material phase purity, grain quality, and grain boundaries with many extrinsic doping and alloying agents (Ag, Cd, Ge…). The reported progress for solution-based precursors has been achieved due to a grain growth in more electronically intrinsic conditions. However, the kesterite device performance is dependent on the majority carrier density and sub-optimal carrier concentrations of 10 14-10 15 cm −3 have been consistently reported. Increasing the majority carrier density by one order of magnitude would increase the efficiency ceiling of kesterite solar cells, making the 20% target much more realistic. In this work, LiClO 4 is introduced as a highly soluble and highly thermally stable Li precursor salt which leads to optimal (>10 16 cm −3) carrier concentration without a significant impact in other relevant optoelectronic properties. The findings presented in this work demonstrate that the interplay between Li-doping and Ag-alloying enables a reproducible and statistically significant improvement in the device performance leading to efficiencies up to 14.1%
Muscle fibre satellite cells are located at a greater distance from capillaries in patients with COPD compared with healthy controls
No full textBackground COPD is a disease characterised by skeletal muscle dysfunction. A spatial relationship exists between satellite cells and muscle fibre capillaries, which has been suggested to be of major importance for satellite cell function. In the present study we compared the spatial relationship between satellite cells and capillaries in patients with COPD and age-matched healthy older adults. Methods Muscle biopsies were obtained from the vastus lateralis of n=18 patients with COPD (8 female, 10 male; age 66 +/- 5 years, mild-to-severe airflow obstruction) and n=18 age-, sex- and body mass index- matched healthy control adults (8 female, 10 male; age 68 +/- 5 years). Immunohistochemistry was used to assess type I/II muscle fibre size, distribution, myonuclear content, satellite cell number and fibre capillarisation. In addition, type I/II muscle fibre satellite cell distance to its nearest capillary was assessed. Results The percentage of type II muscle fibres was significantly greater in patients with COPD (62 +/- 10%) compared with controls (50 +/- 12%, p<0.05). Muscle fibre capillarisation was significantly lower in patients with COPD compared with controls (p<0.05). While satellite cell content was not different between groups, type I and type II satellite cell distance to its nearest capillary was significantly greater in patients with COPD (type I: 21.3 +/- 4.8 pm; type II: 26.7 +/- 9.3 pm) compared with controls (type I: 16.1 +/- 3.5 pm; type II: 22.7 +/- 5.8 pm; p<0.05). Conclusion Satellite cells are located at a greater distance from their nearest capillary in patients with COPD compared with age-matched controls. This increased distance could play a role in impaired satellite cell function in patients with COPD
Screening High-Biomass Grasses for Cadmium Phytoremediation
No full textInvestigating the ability of non-hyperaccumulator plants to grow in soils polluted by cadmium (Cd) and their potential for phytostabilization or phytoextraction is essential for assessing their use in phytomanagement efficiency. Therefore, we evaluated the tolerance of high-biomass grasses to Cd by measuring biomass production and element accumulation and valued them for their suitability for phytoextraction or phytostabilization purposes on moderately Cd-polluted land (total Cd concentration of 7.5 mg kg(-1)) by determining Cd accumulation in the plants and calculating the bioconcentration (Cd BCF) and translocation factors (Cd TF). Among the ten species under investigation, Panicum maximum cv. Massai and Pennisetum glaucum cv. Purpureum Schum showed lower root biomass due to Cd exposure. Cadmium exposure altered element accumulation in some grass species by reducing P, K, and Mg accumulation in P. glaucum cv. Purpureum Schum; K accumulation in P. maximum cv. Massai; Mg accumulation in P. maximum cv. Momba & ccedil;a; Ca, Fe, and Zn accumulation in P. maximum cv. Aruana; and B accumulation in Brachiaria brizantha cv. Piat & atilde;. However, this was not correlated with lowered biomass production, except for K, which was associated with lowered root biomass allocation in P. maximum cv. Massai and P. glaucum cv. Purpureum Schum. Cadmium concentrations decreased from roots to shoots, indicating a clear limitation of upward Cd transport. Although some grasses exhibited a Cd BCF > 1, the Cd TF remained below 0.4 for all tested species. These results indicate that, under moderate Cd pollution, the evaluated grasses are more suitable for Cd phytostabilization than phytoextraction, except for P. maximum cv. Massai and P. glaucum cv. Purpureum Schum, which showed inhibited root growth and may not be efficient over time.We thank the National Council for Scientific and Technological Development—CNPq from Brazil for the research fellowships (Grants #370333/2024-1, #171678/2023-0, #141404/2023-0), the Minas Gerais State Research Support Foundation—FAPEMIG from Brazil for the financial support (Grant #APQ-00819-23), and the Bijzonder Onderzoeksfonds—BOF from Belgium for the incoming mobilities (Grants #BOF22KV09 and #BOF22KV17). This study was also supported by the National Institute of Science and Technology (INCT) on Soil and Food Security, CNPq grant #406577/2022-6
SpannerLib: Embedding Declarative Information Extraction in an Imperative Workflow
No full textDocument spanners have been proposed as a formal framework for declarative Information Extraction (IE) from text, following IE products from the industry and academia. Over the past decade, the framework has been studied thoroughly in terms of expressive power, complexity, and the ability to naturally combine text analysis with relational querying. This demonstration presents SPANNERLIB-a library for embedding document spanners in Python code. SPANNERLIB facilitates the development of IE programs by providing an implementation of Spannerlog (Datalog-based document spanners) that interacts with the Python code in two directions: rules can be embedded inside Python, and they can invoke custom Python code (e.g., calls to ML-based NLP models) via user-defined functions. The demonstration scenarios showcase IE programs, with increasing levels of complexity, within Jupyter Notebook.This work was funded by the Israel Science Foundation (ISF) under grant 768/19. The work of Dean Light and Benny Kimelfeld has been funded by the German Research Foundation (DFG) under grant KI 2348/1-1. S. Vansummeren was supported by the Bijzonder Onderzoeksfonds (BOF) of Hasselt University under Grant No. BOF20ZAP02 as well as the Flanders AI research program
Organic Electrochemical Transistor Channel Materials: Copolymerization Versus Physical Mixing of Glycolated and Alkoxylated Polymers
No full textOrganic electrochemical transistors (OECTs) feature a polymer channel capable of conducting both ions and electronic charges. The choice of the channel material is critical for OECT performance. Many efforts have focused on improving performance via the chemical tunability of conjugated polymers - through backbone, side chain, and molar mass engineering - leading to useful design principles for accumulation-mode OECT materials. However, tuning the chemical structure of conjugated polymers often requires time-consuming optimization of the synthesis route. Meanwhile, variations in molar mass, dispersity, structural defects, and metal content present challenges when attempting to analyze the detailed effects of structural modifications, as multiple performance-determining factors are often (unintentionally) changed at the same time. Therefore, this study explores blended channel materials obtained by physically mixing glycolated and alkoxylated polymers in different ratios, and compares their OECT performance with the corresponding statistical copolymers. It is shown that mixing two well-performing materials creates blends that enable rational tuning of the transistor properties without compromising on performance. Thus, channels based on blends of alkoxylated and glycolated polymers hold promise for OECT technology with tailored response, as only two materials are needed to achieve any desired side chain ratio, simplifying the optimization of OECT characteristics.This project received funding from the European Union’s Horizon 2020 Research and Innovation Program under grant agreement no. 964677 (MITICS). W.M., K.V., L.B., J.V., and A.G. thank the FWO Vlaanderen for
financial support (WEAVE project G025922N and Ph.D. grants 1S70122N and 1S50820N). K.Z., N.B., and D.T. acknowledge the Swiss National Science Foundation (grant 200021E_205216) and the University of Bern for funding. We also thank O. Bardagot for helpful discussions on OECT measurements and data analysis. Use of the Stanford Synchrotron Radiation Light source, SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-76SF00515
Frequency of periprocedural myocardial injury and infarction stratified by cardiac troponin I and cardiac troponin T
No full textBackground: There are different definitions of periprocedural myocardial infarction (PPMI) both in terms of thresholds for cardiac biomarkers and the ancillary criteria for myocardial ischemia. Cardiac Troponin I (cTnI) and cardiac Troponin T (cTnT) are used interchangeably to diagnose PPMI. Objectives: This study evaluated the frequency of periprocedural myocardial injury and infarction as defined by the Society of Cardiovascular Angiography & Interventions (SCAI), the Academic Research Consortium-2 (ARC-2), and the 4th Universal definition of MI (4UDMI) stratified using cTnT versus cTnI, among patients with chronic coronary syndrome (CCS) and unstable angina. Results: Among 830 patients, PPMI rates according to the SCAI, ARC2 and 4UDMI criteria were 4.34 %, 2.05 %, and 4.94 % respectively, with higher rates seen for all definitions when using cTnI versus cTnT (SCAI: 9.84 % vs. 1.91 %, p <0.001; ARC 2: 3.15 % vs. 1.56 %, p = 0.136; and 4UDMI 5.91 % vs. 4.51 %, p = 0.391). Minor and major periprocedural myocardial injury was respectively observed in 58.31 % and 27.10 % of patients, with rates of both significantly higher when using cTnI versus cTnT (Minor: 69.29 % vs. 53.47 %, p < 0.001, Major: 49.21 % vs. 17.36%, p < 0.001). Conclusions: Among patients with CCS and unstable angina, PPMIs defined by SCAI occurred more frequently when using cTnI as opposed to cTnT, whereas the type of troponin had no impact on the incidence of PPMIs according to the ARC-2 and 4UDMI.The Multivessel TALENT trial is an investigator-initiated trial sponsored by the University of Galway, Ireland which received an unrestricted grant from SMT (Sahajanand Medical Technologies, India). The PIONEER IV trial is an investigator-initiated trial sponsored by the University of Galway, Ireland which received an unrestricted grant from SINOMED (Sino Medical Sciences Technology, China). The ASET-JAPAN study was funded by Boston Scientific Japan
Measuring Approximate Functional Dependencies: A Comparative Study
No full textApproximate functional dependencies (AFDs) are functional dependencies (FDs) that “almost” hold in a relation. While various measures have been proposed to quantify the level to which an FD holds approximately, they are difficult to compare and it is unclear which measure is preferable when one needs to discover FDs in real-world data, i.e., data that only approximately satisfies the FD. In response, this paper formally and qualitatively compares AFD measures. We obtain a formal comparison through a novel presentation of measures in terms of Shannon and logical entropy. Qualitatively, we perform a sensitivity analysis w.r.t. structural properties of input relations and quantitatively study the effectiveness of AFD measures for ranking AFDs on real world data. Based on this analysis, we give clear recommendations for the AFD measures to use in practice.We thank Dan Suciu for helpful discussions. S. Vansummeren was supported by the Bijzonder Onderzoeksfonds (BOF) of Hasselt University under
Grant No. BOF20ZAP02. This research received funding from the Flemish
Government under the “Onderzoeksprogramma Artificiele Intelligentie (AI) ¨
Vlaanderen” programme. This work was supported by Research Foundation—Flanders (FWO) for ELIXIR Belgium (I002819N). The resources and
services used in this work were provided by the VSC (Flemish Supercomputer
Center), funded by the Research Foundation – Flanders (FWO) and the
Flemish Government
Hoofdstuk 3. Totstandkoming van de overeenkomst - Afdeling C. Wijziging en beëindiging van de overeenkomst
No full textStructural rigidity, thermochromism and piezochromism of layered hybrid perovskites containing an interdigitated organic bilayer
No full textLayered hybrid perovskites are intensively researched today as highly tunable materials for efficient light harvesting and emitting devices. In classical layered hybrid perovskites, the structural rigidity mainly stems from the crystalline inorganic sublattice, whereas the organic sublattice has a minor contribution to the rigidity of the material. Here, we report two layered hybrid perovskites, (BTa) 2 PbI 4 and (F 2 BTa) 2 PbI 4 , which possess substantially more rigid organic layers due to hydrogen bonding, p-p stacking, and dipole-dipole interactions. These layered perovskites are phase stable under elevated pressures up to 5 GPa and upon temperature lowering down to 80 K. The organic layers, composed of benzotriazole-derived ammonium cations, are among the most rigid in the field of layered hybrid perovskites. We characterize structural rigidity using in situ single-crystal X-ray diffraction during compression up to 5 GPa. Interestingly, the enhanced rigidity of the organic sublattice does not seem to transfer to the inorganic sublattice, leading to an uncommon material configuration with rigid organic layers and deformable inorganic layers. The deformability of the inorganic sublattice is apparent from differences in optical properties between the crystal bulk and surface. Supported by first-principles calculations, we assign these differences to energy transfer processes from the surface to the bulk. The deformability also leads to reversible piezochromism due to shifting of the photoluminescence emission peak with increasing pressure up to 5 GPa, and thermochromism due to narrowing of the photoluminescence emission linewidth with decreasing temperature down to 80 K. This raises the possibility of applying these phase-stable layered hybrid perovskite materials in temperature and/or pressure sensors