Generation of Stable, Low-Divergence Electron Beams by Laser-Wakefield Acceleration in a Steady-State-Flow Gas Cell

Laser-driven, quasimonoenergetic electron beams of up to ~200 MeV in energy have been observed from steady-state-flow fas cells. These beams emitted within a low-divergence cone of 2.1 ± 0.5 mrad FWHM display unprecedented shot-to-shot stability in energy (2.5% rms), pointing (1.4 mrad rms), and charge (16% rms) owing to a highly reproducible gas-density profile within the interaction volume. Laser-wakefield acceleration in gas cells of this type provides a simple and reliable source of relativistic electrons suitable for applications such as the production of extreme-ultraviolet undulator radiation

Functional foods. Reflexions of a scientist regarding a market in expansion

The International Union of Pure and Applied Chemistry (IUPAC) decidió en 2006 impulsar el estudio en América Latina de los nutracéuticos como una oportunidad científica y de interés comercial para toda la comunidad. La inciativa, impulsada por el Subcommittee on Medicinal Chemistry and Drug Development de la IUPAC, presidido por C.R. Ganellin, ha permitido unir esfuerzos de investigadores de América Latina. El proyecto se ha realizado con una presentación general del tema, que se corresponde con este trabajo, al que seguirá inmediatamente una publicación acerca de la situación concreta en diferentes países de la región. El trabajo se presenta de forma simultánea en distintas revistas de manera que se facilite el acceso a él y su siguiente discusión por parte de los interesados, en un intento de crear un clima de interés por el tema sobre la base de la investigación de conocimientos tradicionales y experiencias científicas que permitan la innovación en beneficio de todos, muy especialmente, de las sociedades productoras, así como de las personas que precisen de los compuesto

Mendelian randomization supports bidirectional causality between telomere length and clonal hematopoiesis of indeterminate potential

Human genetic studies support an inverse causal relationship between leukocyte telomere length (LTL) and coronary artery disease (CAD), but directionally mixed effects for LTL and diverse malignancies. Clonal hematopoiesis of indeterminate potential (CHIP), characterized by expansion of hematopoietic cells bearing leukemogenic mutations, predisposes both hematologic malignancy and CAD. TERT (which encodes telomerase reverse transcriptase) is the most significantly associated germline locus for CHIP in genome-wide association studies. Here, we investigated the relationship between CHIP, LTL, and CAD in the Trans-Omics for Precision Medicine (TOPMed) program (n = 63,302) and UK Biobank (n = 47,080). Bidirectional Mendelian randomization studies were consistent with longer genetically imputed LTL increasing propensity to develop CHIP, but CHIP then, in turn, hastens to shorten measured LTL (mLTL). We also demonstrated evidence of modest mediation between CHIP and CAD by mLTL. Our data promote an understanding of potential causal relationships across CHIP and LTL toward prevention of CAD

SARS-CoV-2-specific nasal IgA wanes 9 months after hospitalisation with COVID-19 and is not induced by subsequent vaccination

BACKGROUND: Most studies of immunity to SARS-CoV-2 focus on circulating antibody, giving limited insights into mucosal defences that prevent viral replication and onward transmission. We studied nasal and plasma antibody responses one year after hospitalisation for COVID-19, including a period when SARS-CoV-2 vaccination was introduced. METHODS: In this follow up study, plasma and nasosorption samples were prospectively collected from 446 adults hospitalised for COVID-19 between February 2020 and March 2021 via the ISARIC4C and PHOSP-COVID consortia. IgA and IgG responses to NP and S of ancestral SARS-CoV-2, Delta and Omicron (BA.1) variants were measured by electrochemiluminescence and compared with plasma neutralisation data. FINDINGS: Strong and consistent nasal anti-NP and anti-S IgA responses were demonstrated, which remained elevated for nine months (p < 0.0001). Nasal and plasma anti-S IgG remained elevated for at least 12 months (p < 0.0001) with plasma neutralising titres that were raised against all variants compared to controls (p < 0.0001). Of 323 with complete data, 307 were vaccinated between 6 and 12 months; coinciding with rises in nasal and plasma IgA and IgG anti-S titres for all SARS-CoV-2 variants, although the change in nasal IgA was minimal (1.46-fold change after 10 months, p = 0.011) and the median remained below the positive threshold determined by pre-pandemic controls. Samples 12 months after admission showed no association between nasal IgA and plasma IgG anti-S responses (R = 0.05, p = 0.18), indicating that nasal IgA responses are distinct from those in plasma and minimally boosted by vaccination. INTERPRETATION: The decline in nasal IgA responses 9 months after infection and minimal impact of subsequent vaccination may explain the lack of long-lasting nasal defence against reinfection and the limited effects of vaccination on transmission. These findings highlight the need to develop vaccines that enhance nasal immunity. FUNDING: This study has been supported by ISARIC4C and PHOSP-COVID consortia. ISARIC4C is supported by grants from the National Institute for Health and Care Research and the Medical Research Council. Liverpool Experimental Cancer Medicine Centre provided infrastructure support for this research. The PHOSP-COVD study is jointly funded by UK Research and Innovation and National Institute of Health and Care Research. The funders were not involved in the study design, interpretation of data or the writing of this manuscript

Large-scale phenotyping of patients with long COVID post-hospitalization reveals mechanistic subtypes of disease

One in ten severe acute respiratory syndrome coronavirus 2 infections result in prolonged symptoms termed long coronavirus disease (COVID), yet disease phenotypes and mechanisms are poorly understood1. Here we profiled 368 plasma proteins in 657 participants ≥3 months following hospitalization. Of these, 426 had at least one long COVID symptom and 233 had fully recovered. Elevated markers of myeloid inflammation and complement activation were associated with long COVID. IL-1R2, MATN2 and COLEC12 were associated with cardiorespiratory symptoms, fatigue and anxiety/depression; MATN2, CSF3 and C1QA were elevated in gastrointestinal symptoms and C1QA was elevated in cognitive impairment. Additional markers of alterations in nerve tissue repair (SPON-1 and NFASC) were elevated in those with cognitive impairment and SCG3, suggestive of brain–gut axis disturbance, was elevated in gastrointestinal symptoms. Severe acute respiratory syndrome coronavirus 2-specific immunoglobulin G (IgG) was persistently elevated in some individuals with long COVID, but virus was not detected in sputum. Analysis of inflammatory markers in nasal fluids showed no association with symptoms. Our study aimed to understand inflammatory processes that underlie long COVID and was not designed for biomarker discovery. Our findings suggest that specific inflammatory pathways related to tissue damage are implicated in subtypes of long COVID, which might be targeted in future therapeutic trials

Carbon dioxide gas sensing behavior of nanostructured GdCoO3 prepared by a solution-polymerization method

Stimulation of the localized surface plasmon of metallic nanoparticles has been shown to be an effective mechanism to induce photothermal damage in biological tissues. However, few studies have focused on single cell or subcellular ablation. Our results show that, upon incubation, gold nanostars are internalized by neurons of acute mouse cerebellar brain slices, clustering inside or close to the nucleus. By stimulating the nanostarsí surface plasmon using a femtosecond laser, we show deformation of single nuclei and single cells. Given its precision and extremely localized effect, this is a promising technique for photothermal therapy in areas sensitive to collateral thermal damage such as the nervous system. " 2014 Optical Society of America.",,,,,,"10.1364/BOE.5.004002",,,"http://hdl.handle.net/20.500.12104/43024","http://www.scopus.com/inward/record.url?eid=2-s2.0-84908506803&partnerID=40&md5=367ac33c6fc86bc96a94a8f972a9904

Evi And Np Antibodies In Chronic Chagas Infection: A Report In Patients With Different Clinical Forms [anticorpos Evi E Np Na Infeccao Chagasica Cronica. Estudo Em Pacientes Com Diferentes Formas Clinicas]

[No abstract available]24161

Nanoparticle assisted photothermal deformation of individual neuronal organelles and cells

Stimulation of the localized surface plasmon of metallic nanoparticles has been shown to be an effective mechanism to induce photothermal damage in biological tissues. However, few studies have focused on single cell or subcellular ablation. Our results show that, upon incubation, gold nanostars are internalized by neurons of acute mouse cerebellar brain slices, clustering inside or close to the nucleus. By stimulating the nanostars’ surface plasmon using a femtosecond laser, we show deformation of single nuclei and single cells. Given its precision and extremely localized effect, this is a promising technique for photothermal therapy in areas sensitive to collateral thermal damage such as the nervous system. © 2014 Optical Society of America

An approach to physiologically meaningful distributed inverse solutions to the neuro-electromagnetic inverse problem

The problem of determining the generators of brain electromagnetic activity has no unique solution. The only way to deal this problem, sometimes denominated "the problem of the non-uniqueness", is to restrict the set of possible solutions by using either physiological or mathematical constraints or a combination of both. The main purpose of this work is to propose a method for obtaining a unique distributed solution to the neuro-electromagnetic inverse problem by considering physiological constraints regarding the spatio temporal distribution of the generators. We will focus in discussing distributed inverse solutions (given in terms of the current density vector) which are general enough to include the concentrated inverse solution. Aspects related to the uniqueness of the new inverse solution proposed are discussed that suggest that this solution warrants further development. We consider as the main merit of this proposal the possibility of including new terms extracted from the new developments in neurophysiology

Unusual free radical polymerization of vinyl acetate in anionic microemulsion media

The polymerization of vinyl acetate in one-phase o/w microemulsions stabilized with Aerosol OT (AOT) is examined as a function of concentration and type of initiator (V-50 and KPS) and temperature. Conversions and reaction rates increase with increasing concentration of V-50 and temperature. Faster polymerization rates and higher conversions are achieved with KPS because of the different electrostatic interactions between the charged microemulsion droplets and the free radicals of KPS and V-50. Average molar masses and polydispersity indexes (M̄w/M̄n) are much smaller than those observed in emulsion polymerization using the same surfactant, even at high conversions. Analysis of the molar mass distribution indicates that chain-transfer reactions to monomer are the controlling chain-growth mechanism in the polymerization of vinyl acetate in AOT microemulsions at all conversions