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Summary: 2D Ruddlesden‐Popper (RP) perovskites (R‐NH3)2An−1BnX3n+1 with tailorable photovoltaic features of low toxicity, reduced dimensionality, and defect tolerance hold promise to overcome the main constraints of perovskite solar cells (PSCs). A systematic investigation of the structural and electronic properties of pure and mixed (R‐NH3)2Pb1−xGexI4 systems was performed with and without spin‐orbit coupling (SOC), by using density functional theory (DFT). The organic spacer cations (R‐NH3+)2 of methylammonium (MA‐CH3NH3+) and Phenylethyl ammonium (PEA‐C6H5[CH2]2NH3+) with x = 0.0, 0.25, 0.50, 0.75, 1.0, resulted in the compositionally modified 32‐permutations by systematically substituting the inorganic cations. Short‐range ordering has categorized all studied compositions of (R‐NH3)2Pb0.50Ge0.50I4 into column and battenberg schemes depending on the Ge defect site. The competing effects of octahedral tilting and lattice distortion with bandgap bowing and SOC, across Pb‐Ge compositional systems, provide a systematic strategy to tune bandgaps. By controlling the cations' composition, these mixed 2D‐perovskites outlined the strategy to achieve the desired bandgap and band positions. A rational design approach of low dimensional perovskites was adopted to tune the electronic properties through the spacer and inorganic cation engineering. Our findings expose the scope of monolayer‐based systems as an ideal choice of absorber for the bottom sub‐cell in all‐perovskites 2D‐3D tandem solar cell, harvesting light from visible (2.4 eV) up to infrared (1.2 eV) in the solar spectrum with features of defect tolerance, quantum and dielectric confinement, low bandgap, low effective masses, and high mobility. [ABSTRACT FROM AUTHOR]

Objectives: The objective of this study was to assess the knowledge of acute coronary syndrome (ACS) patients regarding revascularization procedure following coronary angiography at a tertiary care cardiac center of Karachi, Pakistan. Methodology: This descriptive cross-sectional study included newly diagnosed adult patients of ACS admitted to the inpatients department. However, patients with the diagnosis of STsegment elevation myocardial infarction (STEMI) undergone primary PCI were excluded. Patients' knowledge level was assessed by interviewing patients with questionnaire consisted of a total of 10 multiple choice questions. Patients' response against each of the question was verified by the patient's hospital record file and categorized as correct or incorrect. Patients with =70% correct responses (7 out of 10) were categorized to have had sufficient knowledge about revascularization. Results: A total of 130 patients were included with mean age of patients was 57.42±18.43 years and majority of patients, 86.2%(112), were males. Sufficient knowledge regarding revascularization procedure was observed in only 37.7%(49) patients. Male patients had significantly higher frequency of sufficient knowledge than female patients (40.2%(45/112) vs. 22.2%(4/18); p<0.001). Similarly, knowledge level was significantly higher among urban resident than rural residents with frequency of 41.1%(39/95) vs. 28.6%(10/35); p=0.009. Likewise educational status (p<0.030) and age of the patients (p=0.003) were also found to be a significant factors associated with sufficient knowledge. Conclusion: Majority of patients had insufficient knowledge regarding acute coronary syndrome and its revascularization options among ACS patients. It is the need of hour to define strategies to so educate and counsel these patients properly. [ABSTRACT FROM AUTHOR]

Summary: We present a comparative study on the structural, electronic, elastic, and thermoelectric properties of the cubic inverse‐perovskites A3OX (where A = Li, Na, K and X = Cl, Br, I) by density functional theory (DFT). The cohesive, formation, and elastic properties analysis indicates that all studied materials are chemically, thermodynamically, and mechanically stable. Electronic properties reveal that all the inverse A3OX perovskite are direct bandgap semiconductors except Li3OCl and Li3OBr with ionic nature which is confirmed by electron localization function (ELF) analysis. We have also calculated Debye temperature (ΘD) and Grüneisen parameter (γ) to determine the lattice thermal conductivity for all the A3OX materials. Furthermore, thermoelectric (TE) properties are explored by calculating the Seebeck coefficient (S), electronic thermal conductivity, power factor (PF), electrical conductivity (σ/τ), lattice thermal conductivity, and ZT value. Our investigated A3OX inverse‐perovskites provide a fertile base that can improve the overall TE performance for TE applications and green energy production. [ABSTRACT FROM AUTHOR]

This study reports a systematic density functional theory-based analysis on electronic properties of individual doping and codoping of Ti and Ce into GaN. In the case of codoped GaN, the placement of Ti and Ce at nearest neighbour sites appeared as the most stable configuration. The unoccupied states in the case of individual doped material are observed to become occupied after codoping, and a metal-to-metal charge transfer of the Ti-N-Ce character is observed in the material. The interaction between dopants suggests 4f-5d-CB hybridization that opens the way to the exploitation of novel luminescence phenomena. A model showing charge transfer and interaction between the dopants is proposed. [ABSTRACT FROM AUTHOR]

Diagnosis of tumor and definition of tumor borders intraoperatively using fast histopathology is often not sufficiently informative primarily due to tissue architecture alteration during sample preparation step. Confocal laser microscopy (CLE) provides microscopic information of tissue in real-time on cellular and subcellular levels, where tissue characterization is possible. One major challenge is to categorize these images reliably during the surgery as quickly as possible. To address this, we propose an automated tissue differentiation algorithm based on the machine learning concept. During a training phase, a large number of image frames with known tissue types are analyzed and the most discriminant image-based signatures for various tissue types are identified. During the procedure, the algorithm uses the learnt image features to assign a proper tissue type to the acquired image frame. We have verified this method on the example of two types of brain tumors: glioblastoma and meningioma. The algorithm was trained using 117 image sequences containing over 27 thousand images captured from more than 20 patients. We achieved an average cross validation accuracy of better than 83%. We believe this algorithm could be a useful component to an intraoperative pathology system for guiding the resection procedure based on cellular level information. [ABSTRACT FROM AUTHOR]