Differentially heterogeneous hydration environment of the familial mutants of α-synuclein.

The behavior of hydration water around familial Parkinson's disease linked mutants of α-synuclein may be linked to the early-onset of Parkinson's disease. For the first time, this study compares the local structure and dynamics of hydration water around different segments of some of the natural mutants of α-synuclein, i.e.

The Quest for High-Temperature Superconductivity in Nickelates under Ambient Pressure.

Recently, superconductivity with ≈ 80 K was discovered in LaNiO under extreme hydrostatic pressure (>14 GPa). For practical applications, we needed to stabilize this state at ambient pressure. It was proposed that this could be accomplished by substituting La with Ba.

Influence of Atomic Relaxations on the Moiré Flat Band Wave Functions in Antiparallel Twisted Bilayer WS.

Twisting bilayers of transition metal dichalcogenides gives rise to a moiré potential resulting in flat bands with localized wave functions and enhanced correlation effects. In this work, scanning tunneling microscopy is used to image a WS bilayer twisted approximately 3° off the antiparallel alignment. Scanning tunneling spectroscopy reveals localized states in the vicinity of the valence band onset, which is observed to occur first in regions with S-on-S Bernal stacking.

Ferroelectric Switching at Symmetry-Broken Interfaces by Local Control of Dislocations Networks.

Semiconducting ferroelectric materials with low energy polarization switching offer a platform for next-generation electronics such as ferroelectric field-effect transistors. Recently discovered interfacial ferroelectricity in bilayers of transition metal dichalcogenide films provides an opportunity to combine the potential of semiconducting ferroelectrics with the design flexibility of 2D material devices. Here, local control of ferroelectric domains in a marginally twisted WS bilayer is demonstrated with a scanning tunneling microscope at room temperature, and their observed reversible evolution is understood using a string-like model of the domain wall network (DWN).

Assessing the DNA structural integrity via selective annihilation of Watson-Crick hydrogen bonds: Insights from molecular dynamics simulations.

Understanding the role of base pairing and stacking displayed by polynucleotide chains interwind together resulting in a double-helical B-DNA type structure is crucial to gaining access to the sophisticated structural arrangement of DNA. Several computational and experimental studies hinted towards the dominance of base pairing over stacking for duplex stability. To find out how significant the individual Watson-Crick hydrogen bonds are in maintaining the double-helical integrity of the DNA, in the present article, we selectively switched off the hydrogen bonds (one specific bond or their combinations in all the base pairs at a time) via manipulating the force fields for A-T and G-C base pairs.

Evidence for higher order topology in Bi and BiSb.

Higher order topological insulators (HOTIs) are a new class of topological materials which host protected states at the corners or hinges of a crystal. HOTIs provide an intriguing alternative platform for helical and chiral edge states and Majorana modes, but there are very few known materials in this class. Recent studies have proposed Bi as a potential HOTI, however, its topological classification is not yet well accepted.

Hydration Thermodynamics of Familial Parkinson's Disease-Linked Mutants of α-Synuclein.

The hydration thermodynamics of different mutants of α-synuclein (α-syn) related to familial Parkinson's disease (PD) is explored using a computational approach that combines both molecular dynamics simulations in water and integral equation theory of molecular liquids. This analysis focuses on the change in conformational entropy, hydration free energy (HFE), and partial molar volume of α-syn upon mutation. The results show that A53T, A30P, E46K, and H50Q mutants aggregate more readily and display increased HFE and less negative interaction volume than the wild-type α-syn.

Hydration Thermodynamics of the N-Terminal FAD Mutants of Amyloid-β.

The hydration thermodynamics of amyloid-β (Aβ) and its pathogenic familial Alzheimer's disease (FAD) mutants such as A2V, Taiwan (D7H), Tottori (D7N), and English (H6R) and the protective A2T mutant is investigated by a combination of all-atom, explicit water molecular dynamics (MD) simulations and the three-dimensional reference interaction site model (3D-RISM) theory. The change in the hydration free energy on mutation is decomposed into the energetic and entropic components, which comprise electrostatic and nonelectrostatic contributions. An increase in the hydration free energy is observed for A2V, D7H, D7N, and H6R mutations that increase the aggregation propensity of Aβ and lead to an early onset of Alzheimer's disease, while a reverse trend is noted for the protective A2T mutation.

Interaction Volume Is a Measure of the Aggregation Propensity of Amyloid-β.

This study highlights the significance of the partial molar volume of amino acids in predicting the aggregation propensity of an intrinsically disordered protein, amyloid-β (Aβ), and its mutants in aqueous solution. The change in the interaction volume of the protein or mutant is quantitatively correlated with its calculated experimental aggregation propensity. This method also reveals how the interaction volume may be tuned by changing the charge and hydrophobicity of Aβ.

Effect of Alzheimer's Disease Causative and Protective Mutations on the Hydration Environment of Amyloid-β.

This study investigates the local structure and dynamics of hydration water around the intrinsically disordered protein amyloid-β (Aβ) and its Alzheimer's disease causative N-terminus mutants, i.e., A2V, Taiwan (D7H), Tottori (D7N), and English (H6R), and the protective A2T mutant via atomistic MD simulations.

Tip-induced superconductivity coexisting with preserved topological properties in line-nodal semimetal ZrSiS.

ZrSiS was recently shown to be a new material with topologically non-trivial band structure that exhibits multiple Dirac nodes and a robust linear band dispersion up to an unusually high energy of 2 eV. Such a robust linear dispersion makes the topological properties of ZrSiS insensitive to perturbations like carrier doping or lattice distortion. Here, we show that a novel superconducting phase with a remarkably high [Formula: see text] of 7.

Comparison of nine coronary risk scores in evaluating patients presenting to hospital with undifferentiated chest pain.

Introduction: We compared performance of nine risk scores for coronary heart disease (CHD) among patients presenting to an emergency department (ED) with undifferentiated chest pain of possible coronary origin.

Methods: A retrospective study was undertaken of adult patients presenting with chest pain to atertiary hospital ED with no electrocardiographs or troponin results diagnostic of ischemic chest pain (ICP) or acute coronary syndrome at ED presentation, and no clearly evident noncoronary diagnosis. Risk scores were applied using cut-points distinguishing low- from high-risk patients according to discharge diagnosis of noncardiac chest pain (NCCP) or ICP, respectively.

Received care compared to ADP-guided care of patients admitted to hospital with chest pain of possible cardiac origin.

Purpose: To assess the extent to which accelerated diagnostic protocols (ADPs), compared to traditional care, identify patients presenting to emergency departments (EDs) with chest pain who are at low cardiac risk and eligible for early ED discharge.

Patients And Methods: Retrospective study of 290 patients admitted to hospital for further evaluation of chest pain following negative ED workup (no acute ischemic electrocardiogram [ECG] changes or elevation of initial serum troponin assay). Demographic data, serial ECG and troponin results, Thrombolysis in Myocardial Infarction (TIMI) score, cardiac investigations, and outcomes (confirmed acute coronary syndrome [ACS] at discharge and major adverse cardiac events [MACEs]) over 6 months of follow-up were analyzed.

Hydration Water Distribution around Intrinsically Disordered Proteins.

The distribution and local structural order of hydration water in the proximity of intrinsically disordered proteins/regions are investigated within the frame work of three-dimensional (3D)-reference interaction site model theory. The hydration water distribution around the protein surface is quantified in terms of the 3D distribution function and the water-protein radial distribution function (RDF), whereas the local ordering of water molecules around the protein surface is measured in terms of the tetrahedral order parameter. To the best of our knowledge, this is the first theoretical study of the 3D hydration water distribution profiles of disordered proteins.

Underuse of risk assessment and overuse of computed tomography pulmonary angiography in patients with suspected pulmonary thromboembolism.

Background: Evidence suggests the potential overuse of computed tomography pulmonary angiography (CTPA) in patients with suspected pulmonary thromboembolism (PTE) in the absence of consistent use of pre-test clinical prediction rules and D-dimer assays.

Aim: To evaluate use and diagnostic utility of clinical prediction rules and D-dimer assay in patients with suspected PTE and quantify potentially avoidable overuse of CTPA in low risk patients.

Methods: A total of 344 consecutive patients undergoing CTPA at a tertiary hospital was studied with regards to the use of D-dimer assays and clinical prediction rules for PTE.

Mesoscopic superconductivity and high spin polarization coexisting at metallic point contacts on Weyl semimetal TaAs.

A Weyl semimetal is a topologically non-trivial phase of matter that hosts mass-less Weyl fermions, the particles that remained elusive for more than 80 years since their theoretical discovery. The Weyl semimetals exhibit unique transport properties and remarkably high surface spin polarization. Here we show that a mesoscopic superconducting phase with critical temperature T=7 K can be realized by forming metallic point contacts with silver (Ag) on single crystals of TaAs, while neither Ag nor TaAs are superconductors.

Unconventional superconductivity at mesoscopic point contacts on the 3D Dirac semimetal Cd3As2.

Three-dimensional (3D) Dirac semimetals exist close to topological phase boundaries which, in principle, should make it possible to drive them into exotic new phases, such as topological superconductivity, by breaking certain symmetries. A practical realization of this idea has, however, hitherto been lacking. Here we show that the mesoscopic point contacts between pure silver (Ag) and the 3D Dirac semimetal Cd3As2 (ref.

Self-oriented β-crystalline phase in the polyvinylidene fluoride ferroelectric and piezo-sensitive ultrathin Langmuir-Schaefer film.

We report on the direct observation of ferroelectric switching and piezoelectric behaviour in ultrathin polyvinylidene fluoride (PVDF) films prepared by horizontal Langmuir-Schaefer (LS) technique. We have prepared pure β-phase by just increasing the number of LS layers without using additional non-ferroelectric assisting agents. Edge-on oriented CH2-CF2 units of PVDF at the air-water interface enable self-orientation of ferroelectric dipoles by means of the hydrogen bonding network.

One-pot sequential alkynylation and cycloaddition: regioselective construction and biological evaluation of novel benzoxazole-triazole derivatives.

Individually, benzoxazole and triazole moieties are of significant biological interest owing to their importance in drugs and pharmaceuticals. To assess their combined biological impact when woven into one molecule, we designed a novel, regioselective, multicomponent, one-pot (MCOP) approach for the construction of benzoxazole-linked triazoles. The synthesis has been achieved in two sequential steps involving copper-catalyzed alkynylation of benzoxazole followed by a 1,3-dipolar cycloaddition reaction.

Aiming to be NEAT: safely improving and sustaining access to emergency care in a tertiary referral hospital.

Objective: To implement and evaluate strategies for improving access to emergency department (ED) care in a tertiary hospital.

Methods: A retrospective pre-post intervention study using routinely collected data involving all patients presenting acutely to the ED of a major tertiary hospital over a 2-year period. Main outcome measures were changes in: the percentage of patients exiting the ED (all patients, patients discharged directly from the ED, patients admitted to inpatient wards); mean patient transit times in the ED; inpatient mortality rates; rates of ED 'did not wait' and re-presentations within 48 h of ED discharge; and selected safety indicators.

Evaluation and outcomes of patients admitted to a tertiary medical assessment unit with acute chest pain of possible coronary origin.

Objectives: The study aims to (i) profile clinical characteristics, risk estimates of acute coronary syndrome (ACS), use and yield of non-invasive cardiac testing, discharge diagnosis and 30-day outcomes among patients admitted with acute chest pain of possible coronary origin; and (ii) construct a risk stratification algorithm that informs management decisions.

Methods: This is a retrospective cohort study of 130 consecutive patients admitted to a tertiary hospital medical assessment unit between 24 January and 22 March 2012. Estimates of ACS risk were based on Australian guidelines and Thrombolysis in Myocardial Infarction (TIMI) scores.