Home spirometry for idiopathic pulmonary fibrosis: ready for prime time?

Home spirometry in IPF can be used to shorten clinical trials and may enable patient self-management in the future http://ow.ly/Jqft30dGia

Emergent Negative Differential Resistance with an Undisturbed Topological Surface State

Emergent properties in topological insulator heterostructures offer fresh insight not only to understand the system as a whole but also to design new approaches to device engineering at the nanoscale. Here we report the emergent phenomenon of negative differential resistance (NDR) on a topological insulator substrate. Starting with the spin-bearing cobalt fluorophthalocyanine molecule F16CoPc as the fundamental building block and the topological insulator (TI) Bi2Se3 as the host, using scanning tunneling spectroscopy (STS) we observe the emergence of NDR at the F16CoPc/Bi2Se3 interface at a specific negative bias. The topological surface state is also preserved in the process. Realizing NDR at the molecular scale presents a major advance toward designing ultrafast electron tunneling devices as well as high speed, low power, and compact nanoelectronic devices. The undisturbed topological surface state of Bi2Se3 offers added tunability for computer architectures that can be built concomitantly using the topological surface state and NDR

Enhancing Intermolecular Interaction by Cyano Substitution in Copper Phthalocyanine

On-surface molecular self-assembly is one of the key paradigms for understanding intermolecular interactions and molecule–substrate interactions at the atomic scale. Phthalocyanines are planar π-conjugated systems capable of self-assembly and can act as versatile, robust, and tunable templates for surface functionalization. One of the ways to tailor the properties of phthalocyanines is by pendant group substitution. How such a scheme brings about changes in the properties of the phthalocyanines at the nanoscale has not been greatly explored. Here we present an atomic-scale picture of the self-assembly of copper phthalocyanine, CuPc, and compare it with its cyano analogue, CuPc­(CN)_8,on Au(111) using scanning tunneling microscopy (STM) and scanning tunneling spectroscopy (STS) in ultrahigh vacuum (UHV) at 77 K. STM imaging reveals a tetramer unit cell to be the hallmark of each assembly. The periodicity of herringbone reconstruction of Au(111) is unchanged upon CuPc­(CN)₈ adsorption, whereas for CuPc adsorption this periodicity changes. STS measurements show an increment in the highest occupied–lowest unoccupied molecular orbital (HOMO–LUMO) gap from CuPc to CuPc­(CN)₈. Extensive ab initio calculations within density functional theory (DFT) match well with the experimental observations. STM imaging shows adsorption-induced organizational chirality for both assemblies. For CuPc­(CN)₈ at LUMO energy, the individual molecule exhibits an orbital-energy-dependent chirality on top of the existing organizational chirality. It remains achiral at HOMO energy and within the HOMO–LUMO gap. No such peculiarity is seen in the CuPc assembly. This energy-selective chiral picture of CuPc­(CN)₈ is ascribed to the cyano groups that participate in antiparallel dipolar coupling, thereby enhancing intermolecular interaction in the CuPc­(CN)₈ assembly. Thus, our atomically resolved topographic and spectroscopic studies, supplemented by DFT calculations, demonstrate that pendant group substitution is an effective strategy for tweaking intermolecular interactions and for surface functionalization

Off-Stoichiometric Nickel Cobaltite Nanoparticles: Thermal Stability, Magnetization, and Neutron Diffraction Studies

In the present investigation, we report a detailed examination of the effect of off-stoichiometry introduced in NiCo₂O₄ by adding excess cobalt. Thus, we compare and analyze the structural and magnetic properties of the Ni_0.75Co_2.25O₄ and NiCo₂O₄ cubic systems. A low temperature combustion method was utilized to synthesize stoichiometric (NiCo₂O₄) and off-stoichiometric (Ni_0.75Co_2.25O₄) nanoparticles on a large scale. The X-ray diffraction pattern for the sample annealed at high temperature (773 K) shows the presence of a much less intense NiO phase (∼2–5%) in Ni_0.75Co_2.25O₄ as compared to that in the case of NiCo₂O₄ sample (∼15–20%). The Ni 2p and Co 2p XPS spectra reveal the coexistence of Ni²⁺, Ni³⁺, Co²⁺, and Co³⁺ species on the surface of both the NiCo₂O₄ and Ni_0.75Co_2.25O₄ samples in differing proportions. In addition to the basic magnetic characterizations using PPMS, these were also analyzed by neutron diffraction. The off-stoichiometric Ni_0.75Co_2.25O₄ sample shows an interesting magnetic phase conversion from frustrated dipolar system to an enhanced magnetic ordering upon annealing. Local moments on the lattice sites of NiCo₂O₄ and Ni_0.75Co_2.25O₄ samples are further compared by neutron diffraction confirming stronger ordered moments and enhanced structural and thermal stability for the Ni_0.75Co_2.25O₄ sample

Self-Assembly and Photopolymerization of Sub‑2 nm One-Dimensional Organic Nanostructures on Graphene

While graphene has attracted significant attention from the research community due to its high charge carrier mobility, important issues remain unresolved that prevent its widespread use in technologically significant applications such as digital electronics. For example, the chemical inertness of graphene hinders integration with other materials, and the lack of a bandgap implies poor switching characteristics in transistors. The formation of ordered organic monolayers on graphene has the potential to address each of these challenges. In particular, functional groups incorporated into the constituent molecules enable tailored chemical reactivity, while molecular-scale ordering within the monolayer provides sub-2 nm templates with the potential to tune the electronic band structure of graphene via quantum confinement effects. Toward these ends, we report here the formation of well-defined one-dimensional organic nanostructures on epitaxial graphene via the self-assembly of 10,12-pentacosadiynoic acid (PCDA) in ultrahigh vacuum (UHV). Molecular resolution UHV scanning tunneling microscopy (STM) images confirm the one-dimensional ordering of the as-deposited PCDA monolayer and show domain boundaries with symmetry consistent with the underlying graphene lattice. In an effort to further stabilize the monolayer, in situ ultraviolet photopolymerization induces covalent bonding between neighboring PCDA molecules in a manner that maintains one-dimensional ordering as verified by UHV STM and ambient atomic force microscopy (AFM). Further quantitative insights into these experimental observations are provided by semiempirical quantum chemistry calculations that compare the molecular structure before and after photopolymerization

Templating Sub-10 nm Atomic Layer Deposited Oxide Nanostructures on Graphene via One-Dimensional Organic Self-Assembled Monolayers

Molecular-scale control over the integration of disparate materials on graphene is a critical step in the development of graphene-based electronics and sensors. Here, we report that self-assembled monolayers of 10,12-pentacosadiynoic acid (PCDA) on epitaxial graphene can be used to template the reaction and directed growth of atomic layer deposited (ALD) oxide nanostructures with sub-10 nm lateral resolution. PCDA spontaneously assembles into well-ordered domains consisting of one-dimensional molecular chains that coat the entire graphene surface in a manner consistent with the symmetry of the underlying graphene lattice. Subsequently, zinc oxide and alumina ALD precursors are shown to preferentially react with the functional moieties of PCDA, resulting in templated oxide nanostructures. The retention of the original one-dimensional molecular ordering following ALD is dependent on the chemical reaction pathway and the stability of the monolayer, which can be enhanced via ultraviolet-induced molecular cross-linking

Association of epicardial adipose tissue with early structural and functional cardiac changes in Type 2 diabetes

Background Dysregulated epicardial adipose tissue (EAT) may contribute to the development of heart failure in Type 2 diabetes (T2D). This study aimed to evaluate the associations between EAT volume and composition with imaging markers of subclinical cardiac dysfunction in people with T2D and no prevalent cardiovascular disease. Methods Prospective case-control study enrolling participants with and without T2D and no known cardiovascular disease. Two hundred and fifteen people with T2D (median age 63 years, 60 % male) and thirty-nine non-diabetics (median age 59 years, 62 % male) were included. Using computed tomography (CT), total EAT volume and mean CT attenuation, as well as, low attenuation (Hounsfield unit range −190 to −90) EAT volume were quantified by a deep learning method and volumes indexed to body surface area. Associations with cardiac magnetic resonance-derived left ventricular (LV) volumes and strain indices were assessed using linear regression. Results T2D participants had higher LV mass/volume ratio (median 0.89 g/mL [0.82–0.99] vs 0.79 g/mL [0.75–0.89]) and lower global longitudinal strain (GLS; 16.1 ± 2.3 % vs 17.2 ± 2.2 %). Total indexed EAT volume correlated inversely with mean CT attenuation. Low attenuation indexed EAT volume was 2-fold higher (18.8 cm3/m2 vs. 9.4 cm3/m2, p Conclusions Higher EAT volumes seen in T2D are associated with a lower mean CT attenuation. Low attenuation indexed EAT volume is independently, but only weakly, associated with markers of subclinical cardiac dysfunction in T2D.</p

Constructing custom-made radiotranscriptomic signatures of vascular inflammation from routine CT angiograms: a prospective outcomes validation study in COVID-19.

BackgroundDirect evaluation of vascular inflammation in patients with COVID-19 would facilitate more efficient trials of new treatments and identify patients at risk of long-term complications who might respond to treatment. We aimed to develop a novel artificial intelligence (AI)-assisted image analysis platform that quantifies cytokine-driven vascular inflammation from routine CT angiograms, and sought to validate its prognostic value in COVID-19.MethodsFor this prospective outcomes validation study, we developed a radiotranscriptomic platform that uses RNA sequencing data from human internal mammary artery biopsies to develop novel radiomic signatures of vascular inflammation from CT angiography images. We then used this platform to train a radiotranscriptomic signature (C19-RS), derived from the perivascular space around the aorta and the internal mammary artery, to best describe cytokine-driven vascular inflammation. The prognostic value of C19-RS was validated externally in 435 patients (331 from study arm 3 and 104 from study arm 4) admitted to hospital with or without COVID-19, undergoing clinically indicated pulmonary CT angiography, in three UK National Health Service (NHS) trusts (Oxford, Leicester, and Bath). We evaluated the diagnostic and prognostic value of C19-RS for death in hospital due to COVID-19, did sensitivity analyses based on dexamethasone treatment, and investigated the correlation of C19-RS with systemic transcriptomic changes.FindingsPatients with COVID-19 had higher C19-RS than those without (adjusted odds ratio [OR] 2·97 [95% CI 1·43-6·27], p=0·0038), and those infected with the B.1.1.7 (alpha) SARS-CoV-2 variant had higher C19-RS values than those infected with the wild-type SARS-CoV-2 variant (adjusted OR 1·89 [95% CI 1·17-3·20] per SD, p=0·012). C19-RS had prognostic value for in-hospital mortality in COVID-19 in two testing cohorts (high [≥6·99] vs low [InterpretationRadiotranscriptomic analysis of CT angiography scans introduces a potentially powerful new platform for the development of non-invasive imaging biomarkers. Application of this platform in routine CT pulmonary angiography scans done in patients with COVID-19 produced the radiotranscriptomic signature C19-RS, a marker of cytokine-driven inflammation driving systemic activation of coagulation and responsible for adverse clinical outcomes, which predicts in-hospital mortality and might allow targeted therapy.FundingEngineering and Physical Sciences Research Council, British Heart Foundation, Oxford BHF Centre of Research Excellence, Innovate UK, NIHR Oxford Biomedical Research Centre, Wellcome Trust, Onassis Foundation