Organic room-temperature phosphorescence from halogen-bonded organic frameworks: hidden electronic effects in rigidified chromophores.

Development of purely organic materials displaying room-temperature phosphorescence (RTP) will expand the toolbox of inorganic phosphors for imaging, sensing or display applications. While molecular solids were found to suppress non-radiative energy dissipation and make the RTP process kinetically favourable, such an effect should be enhanced by the presence of multivalent directional non-covalent interactions. Here we report phosphorescence of a series of fast triplet-forming tetraethyl naphthalene-1,4,5,8-tetracarboxylates.

The electronic structure of FeV-cofactor in vanadium-dependent nitrogenase.

The electronic structure of the active-site metal cofactor (FeV-cofactor) of resting-state V-dependent nitrogenase has been an open question, with earlier studies indicating that it exhibits a broad = 3/2 EPR signal (Kramers state) having values of ∼4.3 and 3.8, along with suggestions that it contains metal-ions with valencies [1V, 3Fe, 4Fe].

Inside polyMOFs: layered structures in polymer-based metal-organic frameworks.

In this report, we explore the internal structural features of polyMOFs consisting of equal mass ratios of metal-coordinating poly(benzenedicarboxylic acid) blocks and non-coordinating poly(ethylene glycol) (PEG) blocks. The studies reveal alternating lamellae of metal-rich, crystalline regions and metal-deficient non-crystalline polymer, which span the length of hundreds of nanometers. Polymers consisting of random PEG blocks, PEG end-blocks, or non-coordinating poly(cyclooctadiene) (COD) show similar alternation of metal-rich and metal-deficient regions, indicating a universal self-assembly mechanism.

Primary age-related EBV-associated effusion-based lymphoma successfully treated with rituximab and thoracentesis.

EBV-positive HHV8-negative EBL is part of the spectrum of EBV-positive diffuse large B-cell lymphoma NOS. This entity can be labeled as primary age-related EBV-associated EBL and appears to respond well to rituximab and thoracentesis.

Long periodic ripple in a 2D hybrid halide perovskite structure using branched organic spacers.

Two-dimensional (2D) halide perovskites have great promise in optoelectronic devices because of their stability and optical tunability, but the subtle effects on the inorganic layer when modifying the organic spacer remain unclear. Here, we introduce two homologous series of Ruddlesden-Popper (RP) structures using the branched isobutylammonium (IBA) and isoamylammonium (IAA) cations with the general formula (RA)(MA) Pb I (RA = IBA, IAA; MA = methylammonium = 1-4). Surprisingly, the IAA = 2 member results in the first modulated 2D perovskite structure with a ripple with a periodicity of 50.

Orbital energy mismatch engenders high-spin ground states in heterobimetallic complexes.

The spin state in heterobimetallic complexes heavily influences both reactivity and magnetism. Exerting control over spin states in main group-based heterobimetallics requires a different approach as the orbital interactions can differ substantially from that of classic coordination complexes. By deliberately engendering an energetic mismatch within the two metals in a bimetallic complex we can mimic the electronic structure of lanthanides.

Synthetic investigation of competing magnetic interactions in 2D metal-chloranilate radical frameworks.

The discovery of emergent materials lies at the intersection of chemistry and condensed matter physics. Synthetic chemistry offers a pathway to create materials with the desired physical and electronic structures that support fundamentally new properties. Metal-organic frameworks are a promising platform for bottom-up chemical design of new materials, owing to their inherent chemical predictability and tunability relative to traditional solid-state materials.

Towards a unified understanding of the copper sites in particulate methane monooxygenase: an X-ray absorption spectroscopic investigation.

The enzymatic conversion of the greenhouse gas, methane, to a liquid fuel, methanol, is performed by methane monooxygenases (MMOs) under mild conditions. The copper stoichiometry of particulate MMO (pMMO) has been long debated, with a dicopper site previously proposed on the basis of a 2.51 Å Cu-Cu feature in extended X-ray absorption fine structure (EXAFS) data.

Superstructured Biomaterials Formed by Exchange Dynamics and Host-Guest Interactions in Supramolecular Polymers.

Dynamic and reversible assembly of molecules is ubiquitous in the hierarchical superstructures of living systems and plays a key role in cellular functions. Recent work from the laboratory reported on the reversible formation of such superstructures in systems of peptide amphiphiles conjugated to oligonucleotides and electrostatically complimentary peptide sequences. Here, a supramolecular system is reported upon where exchange dynamics and host-guest interactions between -cyclodextrin and adamantane on peptide amphiphiles lead to superstructure formation.

Near-infrared stimulation of the auditory nerve: A decade of progress toward an optical cochlear implant.

Objectives: We provide an appraisal of recent research on stimulation of the auditory system with light. In particular, we discuss direct infrared stimulation and ongoing controversies regarding the feasibility of this modality. We also discuss advancements and barriers to the development of an optical cochlear implant.

COVID-19 phobia across the world: Impact of resilience on COVID-19 phobia in different nations.

Aim: This research study focused on exploring the impact of resilience on COVID-19 phobia (C19P) among individuals from different nations including a cluster of European countries, India, Indonesia, Pakistan and the United States of America (USA).

Method: We recruited research participants via disseminating an electronic survey on Facebook Messenger (FM) that included 812 participants. The electronic survey assessed unidentifiable demographic information, the COVID-19 Phobia Scale (C19P-S; Arpaci et al.

Optically Activated 3D Thin-Shell TiO for Super-Sensitive Chemoresistive Responses: Toward Visible Light Activation.

One of the well-known strategies for achieving high-performance light-activated gas sensors is to design a nanostructure for effective surface responses with its geometric advances. However, no study has gone beyond the benefits of the large surface area and provided fundamental strategies to offer a rational structure for increasing their optical and chemical performances. Here, a new class of UV-activated sensing nanoarchitecture made of highly periodic 3D TiO, which facilitates 55 times enhanced light absorption by confining the incident light in the nanostructure, is prepared as an active gas channel.

Sacrificial Synthesis of Supported Ru Single Atoms and Clusters on N-doped Carbon Derived from Covalent Triazine Frameworks: A Charge Modulation Approach.

High-temperature pyrolysis of nitrogen (N)-rich, crystalline porous organic architectures in the presence of a metal precursor is an important chemical process in heterogeneous catalysis for the fabrication of highly porous N-carbon-supported metal catalysts. Herein, covalent triazine framework (CTF) and CTF-I (that is, CTF after charge modulation with iodomethane) are presented as sacrificial templates, for the synthesis of carbon-supported Ru catalysts-Ru-CTF-900 and Ru-CTF-I-900 respectively, following high-temperature pyrolysis at 900 °C under N atmosphere. Predictably, the dispersed Ru on pristine CTF carrier suffered severe sintering of the Ru nanoparticles (NPs) during heat treatment at 900 °C.

Seed size and capitulum position drive germination and dormancy responses to projected warming for the threatened dune endemic (Asteraceae).

Among coastal plant species at risk from rapid environmental changes is the North American Great Lakes dune endemic . Despite being listed as federally threatened, little is known about how seed attributes influence germination and dormancy-break patterns in the context of climate change. Following a previous work where we found differences in the number and weight of seeds among capitulum positions and study sites, here we examine the effects of seed attributes (capitulum position, seed weight, and site of origin) on the proportion and timing of seed germination under temperature treatments that simulate projected warming in the Great Lakes (20/10, 25/10, and 30/10°C day/night).

Toughening of a Soft Polar Polythiophene through Copolymerization with Hard Urethane Segments.

Polar polythiophenes with oligoethylene glycol side chains are exceedingly soft materials. A low glass transition temperature and low degree of crystallinity prevents their use as a bulk material. The synthesis of a copolymer comprising 1) soft polythiophene blocks with tetraethylene glycol side chains, and 2) hard urethane segments is reported.

Thienoisoindigo (TII)-Based Quinoidal Small Molecules for High-Performance n-Type Organic Field Effect Transistors.

A novel quinoidal thienoisoindigo (TII)-containing small molecule family with dicyanomethylene end-capping units and various alkyl chains is synthesized as n-type organic small molecules for solution-processable organic field effect transistors (OFETs). The molecular structure of the 2-hexyldecyl substituted derivative, , is determined via single-crystal X-ray diffraction and shows that the core is planar and exhibits molecular layers stacked in a "face-to-face" arrangement with short core intermolecular distances of 3.28 Å.

Effects of anthropogenic habitat disturbance and infection on a sentinel species' gut bacteria.

Habitat disturbance, a common consequence of anthropogenic land use practices, creates human-animal interfaces where humans, wildlife, and domestic species can interact. These altered habitats can influence host-microbe dynamics, leading to potential downstream effects on host physiology and health. Here, we explored the effect of ecological overlap with humans and domestic species and infection with the protozoan parasite on the bacteria of black and gold howler monkeys (), a key sentinel species, in northeastern Argentina.

Development and validation of language and visuospatial composite scores in ADNI.

Introduction: Composite scores may be useful to summarize overall language or visuospatial functioning in studies of older adults.

Methods: We used item response theory to derive composite measures for language (ADNI-Lan) and visuospatial functioning (ADNI-VS) from the cognitive battery administered in the Alzheimer's Disease Neuroimaging Initiative (ADNI). We evaluated the scores among groups of people with normal cognition, mild cognitive impairment (MCI), and Alzheimer's disease (AD) in terms of responsiveness to change, association with imaging findings, and ability to differentiate between MCI participants who progressed to AD dementia and those who did not progress.

Self-Healing of Electrical Damage in Polymers.

Polymers are widely used as dielectric components and electrical insulations in modern electronic devices and power systems in the industrial sector, transportation, and large appliances, among others, where electrical damage of the materials is one of the major factors threatening the reliability and service lifetime. Self-healing dielectric polymers, an emerging category of materials capable of recovering dielectric and insulating properties after electrical damage, are of promise to address this issue. This paper aims at summarizing the recent progress in the design and synthesis of self-healing dielectric polymers.

Resource competition shapes biological rhythms and promotes temporal niche differentiation in a community simulation.

Competition for resources often contributes strongly to defining an organism's ecological niche. Endogenous biological rhythms are important adaptations to the temporal dimension of niches, but how other organisms influence such temporal niches has not been much studied, and the role of competition in particular has been even less examined. We investigated how interspecific competition and intraspecific competition for resources shape an organism's activity rhythms.

A Pilot Program Assessing Bronchoscopy Training and Program Initiation in a Low-income Country.

Background: Flexible bronchoscopy is an essential procedure for the evaluation and management of the pulmonary disease. However, this technology and related training is not available in many low-middle income countries (LMICs). We conducted a pilot training program for flexible bronchoscopy in Uganda.

Public Health and Climate Benefits and Trade-Offs of U.S. Vehicle Electrification.

Vehicle electrification is a common climate change mitigation strategy, with policymakers invoking co-beneficial reductions in carbon dioxide (CO) and air pollutant emissions. However, while previous studies of U.S.

Aβ oligomer induced cognitive impairment and evaluation of ACU193-MNS-based MRI in rabbit.

Introduction: Amyloid-beta oligomers (AβOs) accumulate in Alzheimer's disease and may instigate neuronal pathology and cognitive impairment. We examined the ability of a new probe for molecular magnetic resonance imaging (MRI) to detect AβOs in vivo, and we tested the behavioral impact of AβOs injected in rabbits, a species with an amino acid sequence that is nearly identical to the human sequence.

Methods: Intracerebroventricular (ICV) injection with stabilized AβOs was performed.

Designing Policy Solutions to Build a Healthier Rural America.

Disparities exist in the health, livelihood, and opportunities for the 46-60 million people living in America's rural communities. Rural communities across the United States need a new energy and focus concentrated around health and health care that allows for the designing capturing, and spreading of existing and new innovations. This paper aims to provide a framework for policy solutions to build a healthier rural America describing both the current state of rural health policy and the policies and practices in states that could be used as a national model for positive change.