Quantitative Edge Analysis Can Differentiate Pancreatic Carcinoma from Normal Pancreatic Parenchyma.

This study aimed to introduce specific image feature analysis, focusing on pancreatic margins, and to provide a quantitative measure of edge irregularity, evidencing correlations with the presence/absence of pancreatic adenocarcinoma. We selected 50 patients (36 men, 14 women; mean age 63.7 years) who underwent Multi-detector computed tomography (MDCT) for the staging of pancreatic adenocarcinoma of the tail of the pancreas.

Screening and Antiscreening Effects in Endohedral Nanotubes.

Recently we investigated from first-principles screening properties in systems where small molecules, characterized by a finite electronic dipole moment, are encapsulated in different nanocages. The most relevant result was the observation of an antiscreening effect in alkali-halide nanocages characterized by ionic bonds: in fact, due to the relative displacement of positive and negative ions, induced by the dipole moment of the encapsulated molecule, these cages act as dipole-field amplifiers, different from what is observed in carbon fullerene nanocages, which exhibit instead a pronounced screening effect. Here we extend the study to another class of nanostructures: the nanotubes.

Superfluidity Meets the Solid State: Frictionless Mass Transport through a (5,5) Carbon Nanotube.

Superfluidity is a well-characterized quantum phenomenon which entails frictionless motion of mesoscopic particles through a superfluid, such as ^{4}He or dilute atomic gases at very low temperatures. As shown by Landau, the incompatibility between energy and momentum conservation, which ultimately stems from the spectrum of the elementary excitations of the superfluid, forbids quantum scattering between the superfluid and the moving mesoscopic particle, below a critical speed threshold. Here, we predict that frictionless motion can also occur in the absence of a standard superfluid, i.

Quantum-mechanical water-flow enhancement through a sub-nanometer carbon nanotube.

Experimental observations unambiguously reveal quasi-frictionless water flow through nanometer-scale carbon nanotubes (CNTs). Classical fluid mechanics is deemed unfit to describe this enhanced flow, and recent investigations indicated that quantum mechanics is required to interpret the extremely weak water-CNT friction. In fact, by quantum scattering, water can only release discrete energy upon excitation of electronic and phononic modes in the CNT.

MBD + C: How to Incorporate Metallic Character into Atom-Based Dispersion Energy Schemes.

The dispersion component of the van der Waals interaction in low-dimensional metals is known to exhibit anomalous "Type-C non-additivity" [ 1157]. This causes dispersion energy behavior at asymptotically large separations that is missed by popular atom-based schemes for dispersion energy calculations. For example, the dispersion interaction energy between parallel metallic nanotubes at separation falls off asymptotically as approximately , whereas current atom-based schemes predict asymptotically.

Quantitative edge analysis of pancreatic margins in patients with head pancreatic tumors: correlations between pancreatic margins and the onset of postoperative pancreatic fistula.

Objective: To assess the correlation between pancreatic quantitative edge analysis as a surrogate of parenchymal stiffness and the incidence of postoperative pancreatic fistula (POPF), in patients undergoing pancreaticoduodenectomy (PD).

Methods: All consecutive patients who underwent PD at our Institution between March 2018 and November 2019 with an available preoperative CT were included. Pancreatic margin score (PMS) was calculated through computer-assisted quantitative edge analysis on the margins of the pancreatic body and tail (the expected pancreatic remnant) on non-contrast scans with in-house software.

Quantitative Edge Analysis of Pancreatic Margins in Patients with Chronic Pancreatitis: A Correlation with Exocrine Function.

Background: Many efforts have been made to improve accuracy and sensitivity in diagnosing chronic pancreatitis (CP), obtaining quantitative assessments related to functional data. Our purpose was to correlate a computer-assisted analysis of pancreatic morphology, focusing on glandular margins, with exocrine function-measured by fecal elastase values-in chronic pancreatitis patients.

Methods: We retrospectively reviewed chronic pancreatitis patients who underwent fecal elastase assessment and abdominal MRI in our institute within 1 year.

Experimental and Theoretical Studies toward Superior Anti-corrosive Nanocomposite Coatings of Aminosilane Wrapped Layer-by-Layer Graphene Oxide@MXene/Waterborne Epoxy.

Herein, layer-by-layer MXene/graphene oxide nanosheets wrapped with 3-aminopropyltriethoxy silane (abbreviated as F-GO@MXene) are proposed as an anti-corrosion promoter for waterborne epoxies. The GO@MXene nanohybrid is synthesized by a solvothermal reaction to produce a multi-layered 2D structure without defects. Then, the GO@MXene is modified by silane wrapping under a reflux reaction, in order to achieve chemical stability and to create active sites on the nanohybrid surface for reaction with the polymer matrix of the coating.

Exact Sum-Rule Approach to Polarizability and Asymptotic van der Waals Functionals─Derivation of Exact Single-Particle Benchmarks.

Using a sum-rule approach, we develop an exact theoretical framework for polarizability and asymptotic van der Waals correlation energy functionals of small isolated objects. The functionals require only monomer ground-state properties as input. Functional evaluation proceeds via solution of a single position-space differential equation, without the usual summations over excited states or frequency integrations.

Colossal Enhancement of Atomic Force Response in van der Waals Materials Arising from Many-Body Electronic Correlations.

Understanding complex materials at different length scales requires reliably accounting for van der Waals (vdW) interactions, which stem from long-range electronic correlations. While the important role of many-body vdW interactions has been extensively documented for the stability of materials, much less is known about the coupling between vdW interactions and atomic forces. Here we analyze the Hessian force response matrix for a single and two vdW-coupled atomic chains to show that a many-body description of vdW interactions yields atomic force response magnitudes that exceed the expected pairwise decay by 3-5 orders of magnitude for a wide range of separations between perturbed and observed atoms.

Optical van-der-Waals forces in molecules: from electronic Bethe-Salpeter calculations to the many-body dispersion model.

Molecular forces induced by optical excitations are connected to a wide range of phenomena, from chemical bond dissociation to intricate biological processes that underpin vision. Commonly, the description of optical excitations requires the solution of computationally demanding electronic Bethe-Salpeter equation (BSE). However, when studying non-covalent interactions in large-scale systems, more efficient methods are desirable.

Real Space-Real Time Evolution of Excitonic States Based on the Bethe-Salpeter Equation Method.

We introduce a method for constructing localized excitations and simulating the real time dynamics of excitons at the Many-Body Perturbation Theory Bethe-Salpeter Equation level. We track, on the femto-seconds scale, electron injection from a photoexcited dye into a semiconducting slab. From the time-dependent many-body wave function we compute the spatial evolution of the electron and of the hole; full electron injection is attained within 5 fs.

Tunable van der Waals interactions in low-dimensional nanostructures.

Non-covalent van der Waals interactions play a major role at the nanoscale, and even a slight change in their asymptotic decay could produce a major impact on surface phenomena, self-assembly of nanomaterials, and biological systems. By a full many-body description of vdW interactions in coupled carbyne-like chains and graphenic structures, here, we demonstrate that both modulus and a range of interfragment forces can be effectively tuned, introducing mechanical strain and doping (or polarizability change). This result contrasts with conventional pairwise vdW predictions, where the two-body approximation essentially fixes the asymptotic decay of interfragment forces.

Many-body van der Waals interactions beyond the dipole approximation.

Long-ranged van der Waals (vdW) interactions are most often treated via Lennard-Jones approaches based on the combination of two-body and dipolar approximations. While beyond-dipole interactions and many-body contributions were separately addressed, little is known about their combined effect, especially in large molecules and relevant nanoscale systems. Here, we provide a full many-body description of vdW interactions beyond the dipole approximation, efficiently applicable to large-scale systems.

Vemurafenib plus Rituximab in Refractory or Relapsed Hairy-Cell Leukemia.

Background: Hairy-cell leukemia (HCL) is a CD20+ indolent B-cell cancer in which a BRAF V600E kinase-activating mutation plays a pathogenetic role. In clinical trials involving patients with refractory or relapsed HCL, the targeting of BRAF V600E with the oral BRAF inhibitor vemurafenib led to a response in 91% of the patients; 35% of the patients had a complete response. However, the median relapse-free survival was only 9 months after treatment was stopped.

Dietary Oxalate Loading Impacts Monocyte Metabolism and Inflammatory Signaling in Humans.

Unlabelled: Diet has been associated with several metabolic diseases and may impact immunity. Increased consumption of meals with high oxalate content may stimulate urinary calcium oxalate (CaOx) crystals, which are precursors to CaOx kidney stones. We previously reported that CaOx stone formers have decreased monocyte cellular bioenergetics compared to healthy participants and oxalate reduces monocyte metabolism and redox status .

From quantum to continuum mechanics in the delamination of atomically-thin layers from substrates.

Anomalous proximity effects have been observed in adhesive systems ranging from proteins, bacteria, and gecko feet suspended over semiconductor surfaces to interfaces between graphene and different substrate materials. In the latter case, long-range forces are evidenced by measurements of non-vanishing stress that extends up to micrometer separations between graphene and the substrate. State-of-the-art models to describe adhesive properties are unable to explain these experimental observations, instead underestimating the measured stress distance range by 2-3 orders of magnitude.

Trends in the Change in Graphene Conductivity upon Gas Adsorption: The Relevance of Orbital Distortion.

The experimental ability to alter graphene (G) conductivity by adsorption of a single gas molecule is promoting the development of ultra-high-sensitivity gas detectors and could ultimately provide a novel playground for future nanoelectronics devices. At present, the underpinning effect is broadly attributed to a variation of G carrier concentration, caused by an adsorption-induced Fermi-level shift. By means of first-principle Kubo-Greenwood calculations, here we demonstrate that adsorbate-induced orbital distortion could also lead to small but finite G conductivity changes, even in the absence of Fermi-level shifts.

Inherent Biophysical Properties Modulate the Toxicity of Soluble Amyloidogenic Light Chains.

In light chain amyloidosis (AL), fibrillar deposition of monoclonal immunoglobulin light chains (LCs) in vital organs, such as heart, is associated with their severe dysfunction. In addition to the cellular damage caused by fibril deposition, direct toxicity of soluble prefibrillar amyloidogenic proteins has been reported, in particular, for cardiotoxicity. However, the molecular bases of proteotoxicity by soluble LCs have not been clarified.

School Burnout, Relational, and Organizational Factors.

Work stress and burnout affect teachers to a significant extent. The objective of this study is to evaluate and compare the impact of relational and organizational factors on teacher burnout in two samples of primary school teachers, one Italian (Naples) and the other Swiss (Cantone Ticino). The hypothesis is that, given the socio-cultural and economic differences of the two contexts, the variables under investigation impact teacher burnout differently.

van der Waals interactions in DFT using Wannier functions without empirical parameters.

A new implementation is proposed for including van der Waals (vdW) interactions in Density Functional Theory (DFT) using the Maximally Localized Wannier Functions (MLWFs), which is free from empirical parameters. With respect to the previous DFT/vdW-WF2 method, in the present DFT/vdW-WF2-x approach, the empirical, short-range, damping function is replaced by an estimate of the Pauli exchange repulsion, also obtained by the MLWF properties. Applications to systems contained in the popular S22 molecular database and to the case of an Ar atom interacting with graphite and comparison with reference data indicate that the new method, besides being more physically founded, also leads to a systematic improvement in the description of vdW-bonded systems.

Faraday-like Screening by Two-Dimensional Nanomaterials: A Scale-Dependent Tunable Effect.

The modulation of electric fields by mono- or few-layer two-dimensional (2D) nanomaterials embodies a major challenge through vast technological areas, including 2D nanoscale electronics, ultrathin cable shielding, and nanostructured battery and supercapacitor electrodes. By a quantum-mechanical analysis of Faraday-like electrostatic screening due to diverse 2D nanolayers we demonstrate that electric field screening is triggered by charge response nonlocality. The effective screening factor is not only influenced by average polarizability but further exhibits nontrivial scalings with respect to surface distance: while ideal 2D metallic systems cause complete Faraday-cage screening, semimetallic graphene yields a finite, roughly scale-independent field reduction factor.

Anomalous van der Waals-Casimir interactions on graphene: A concerted effect of temperature, retardation, and non-locality.

Dispersion forces play a major role in graphene, largely influencing adhesion of adsorbate moieties and stabilization of functional multilayered structures. However, the reliable prediction of dispersion interactions on graphene up to the relevant ∼10 nm scale is an extremely challenging task: in fact, electromagnetic retardation effects and the highly non-local character of π electrons can imply sizeable qualitative variations of the interaction with respect to known pairwise approaches. Here we address both issues, determining the finite-temperature van der Waals (vdW)-Casimir interaction for point-like and extended adsorbates on graphene, explicitly accounting for the non-local dielectric permittivity.

Excellent outcomes of 2G-TKI therapy after imatinib failure in chronic phase CML patients.

Second-generation tyrosine kinase inhibitors (2G-TKIs) dasatinib and nilotinib produced historical rates of about 50% complete cytogenetic response (CCyR) and about 40% major molecular response (MMR) in chronic myeloid leukaemia (CML) patients failing imatinib. Direct comparisons between dasatinib and nilotinib are lacking, and few studies addressed the dynamics of deep molecular response (DMR) in a "real-life" setting. We retrospectively analyzed 163 patients receiving dasatinib ( = 95) or nilotinib ( = 68) as second-line therapy after imatinib.