436 research outputs found
Atividade antimicrobiana de subfrações padronizadas da planta Arrabidaea chica Verl.
Este estudo analisou o potencial terapêutico de extratos e subfrações padronizadas da planta amazônica Arrabidaea chica, visando seu uso tópico como medicamento e eficácia comprovada em doenças cutâneas
Cyclotron resonant scattering feature simulations. I. Thermally averaged cyclotron scattering cross sections, mean free photon-path tables, and electron momentum sampling
Electron cyclotron resonant scattering features (CRSFs) are observed as
absorption-like lines in the spectra of X-ray pulsars. A significant fraction
of the computing time for Monte Carlo simulations of these quantum mechanical
features is spent on the calculation of the mean free path for each individual
photon before scattering, since it involves a complex numerical integration
over the scattering cross section and the (thermal) velocity distribution of
the scattering electrons.
We aim to numerically calculate interpolation tables which can be used in
CRSF simulations to sample the mean free path of the scattering photon and the
momentum of the scattering electron. The tables also contain all the
information required for sampling the scattering electron's final spin.
The tables were calculated using an adaptive Simpson integration scheme. The
energy and angle grids were refined until a prescribed accuracy is reached. The
tables are used by our simulation code to produce artificial CRSF spectra. The
electron momenta sampled during these simulations were analyzed and justified
using theoretically determined boundaries.
We present a complete set of tables suited for mean free path calculations of
Monte Carlo simulations of the cyclotron scattering process for conditions
expected in typical X-ray pulsar accretion columns (0.01<B/B_{crit}<=0.12,
where B_{crit}=4.413x10^{13} G and 3keV<=kT<15keV). The sampling of the tables
is chosen such that the results have an estimated relative error of at most
1/15 for all points in the grid. The tables are available online at
http://www.sternwarte.uni-erlangen.de/research/cyclo.Comment: A&A, in pres
A aplicabilidade da comunicação na psicologia
This article aims to explain how communication affects the individual, both organizationally and clinically. We begin by defining what are the inherent aspects of communication, the different types of communication, and how they have different outcomes in social relationships. Then we explain the importance of communication and the right type of communication in the organizational and clinical environment, demonstrating a specific burnout situation where communication failure has disrupted and damaged people’s lives in the organizational context and also how communication, or assertive communication, has an impact on marital relations. This makes it urgent to become aware that we must open ourselves to COMMUNICATION.Este trabalho tem como objetivo explicar como a comunicação afeta o indivíduo, quer a nível organizacional, quer a nível clínico. Começamos assim por definir quais os aspetos inerentes à comunicação, os diferentes tipos de comunicação e como estes têm diferentes resultados nas relações sociais. De seguida, explicamos o quão importante é a comunicação e o tipo de comunicação adequado no ambiente organizacional e no clínico, demonstrando uma situação especifica de burnout, cuja falha de comunicação atrapalhou e prejudicou a vida de indivíduos, no contexto organizacional; e ainda como a comunicação, ou a comunicação assertiva mais especificamente, tem impacto nas relações conjugais. Torna-se assim urgente a tomada de consciência de que devemo-nos abrir para A COMUNICAÇÃO
Removal of Paracetamol and Cu2+ from Water by Using Porous Carbons Derived from Agrowastes
Publisher Copyright:
© 2023 by the authors.Dende and babassu coconuts are largely used in tropical countries, namely in Brazil, for the extraction of oils from kernels. The remaining biowastes are industrially processed to produce porous carbons (PCs). PCs derived from dende and babassu biowastes and produced at an industrial scale have been characterized by textural, chemical, and ecotoxicological parameters. A commercial activated carbon (CC) of mineral origin has been used as a benchmarking material. Although the CC sample presented a higher surface area (SBET = 1083 m2/g), the PCs derived from the biowastes were richer in micropores (Vmicro = 0.25–0.26 cm3/g), while the CC carbon presented wider pore size distribution with a higher mesopore volume (Vmeso = 0.41 cm3/g). All the adsorbents used in this work have shown a non-acute ecotoxic behavior for the bacterium Vibrio fischeri (EC50-30 min > 99% v/v). The adsorbents have been tested for paracetamol and Cu2+ adsorption in mono- and bicomponent solutions. The uptake capacities of paracetamol (qe, 98–123 mg g−1) and Cu2+ (qe, 15–18 mg g−1) from monocomponent solutions were similar to the ones obtained in the bicomponent solutions, indicating no competition or cooperative effects but a site-specific adsorption. This finding represents an advantage for the removal of these adsorbates when present in the same solution as they can be adsorbed under similar rates as in the single systems. Paracetamol adsorption was related to micropore filling, π-π interactions, and H-bonding, whereas Cu2+ removal was attributed to the cation exchange mechanism and complexation to the hydroxyl groups at the carbons’ surface.publishersversionpublishe
Evidences for lipid involvement in SARS-CoV-2 cytopathogenesis
The pathogenesis of SARS-CoV-2 remains to be completely understood, and detailed SARS-CoV-2 cellular cytopathic effects requires definition. We performed a comparative ultrastructural study of SARS-CoV-1 and SARS-CoV-2 infection in Vero E6 cells and in lungs from deceased COVID-19 patients. SARS-CoV-2 induces rapid death associated with profound ultrastructural changes in Vero cells. Type II pneumocytes in lung tissue showed prominent altered features with numerous vacuoles and swollen mitochondria with presence of abundant lipid droplets. The accumulation of lipids was the most striking finding we observed in SARS-CoV-2 infected cells, both in vitro and in the lungs of patients, suggesting that lipids can be involved in SARS-CoV-2 pathogenesis. Considering that in most cases, COVID-19 patients show alteration of blood cholesterol and lipoprotein homeostasis, our findings highlight a peculiar important topic that can suggest new approaches for pharmacological treatment to contrast the pathogenicity of SARS-CoV-2
In vivo molecular imaging of chemokine receptor CXCR4 expression in patients with advanced multiple myeloma
CXCR4 is a G-protein-coupled receptor that mediates recruitment of blood cells toward its ligand SDF-1. In cancer, high CXCR4 expression is frequently associated with tumor dissemination and poor prognosis. We evaluated the novel CXCR4 probe [(68)Ga]Pentixafor for in vivo mapping of CXCR4 expression density in mice xenografted with human CXCR4-positive MM cell lines and patients with advanced MM by means of positron emission tomography (PET). [(68)Ga]Pentixafor PET provided images with excellent specificity and contrast. In 10 of 14 patients with advanced MM [(68)Ga]Pentixafor PET/CT scans revealed MM manifestations, whereas only nine of 14 standard [(18)F]fluorodeoxyglucose PET/CT scans were rated visually positive. Assessment of blood counts and standard CD34(+) flow cytometry did not reveal significant blood count changes associated with tracer application. Based on these highly encouraging data on clinical PET imaging of CXCR4 expression in a cohort of MM patients, we conclude that [(68)Ga]Pentixafor PET opens a broad field for clinical investigations on CXCR4 expression and for CXCR4-directed therapeutic approaches in MM and other diseases
X-ray emission from magnetized neutron star atmospheres at low mass accretion rates. I. Phase-averaged spectrum
Recent observations of X-ray pulsars at low luminosities allow, for the first
time, to compare theoretical models for the emission from highly magnetized
neutron star atmospheres at low mass accretion rates ( g s) with the broadband X-ray data. The purpose of this paper
is to investigate the spectral formation in the neutron star atmosphere at low
and to conduct a parameter study of physical properties of the
emitting region. We obtain the structure of the static atmosphere, assuming
that Coulomb collisions are the dominant deceleration process. The upper part
of the atmosphere is strongly heated by the braking plasma, reaching
temperatures of 30-40 keV, while its denser isothermal interior is much cooler
(~2 keV). We numerically solve the polarized radiative transfer in the
atmosphere with magnetic Compton scattering, free-free processes, and
non-thermal cyclotron emission due to possible collisional excitations of
electrons. The strongly polarized emitted spectrum has a double-hump shape that
is observed in low-luminosity X-ray pulsars. A low-energy "thermal" component
is dominated by extraordinary photons that can leave the atmosphere from deeper
layers due to their long mean free path at soft energies. We find that a
high-energy component is formed due to resonant Comptonization in the heated
non-isothermal part of the atmosphere even in the absence of collisional
excitations. The latter, however, affect the ratio of the two components. A
strong cyclotron line originates from the optically thin, uppermost zone. A fit
of the model to NuSTAR and Swift/XRT observations of GX 304-1 provides an
accurate description of the data with reasonable parameters. The model can thus
reproduce the characteristic double-hump spectrum observed in low-luminosity
X-ray pulsars and provides insights into spectral formation.Comment: 18 pages, 10 figures, A&A accepte
Modelos de negócio e comunicação social: “telcos”, legacy media, novos media e start-ups jornalísticas em navegação digital: estudo prospectivo (2015-2020)
Este não é um estudo “chave na mão” que solucione os problemas do sector da comunicação social portuguesa, do sector em outros países ou à escala global. O estudo é “apenas” um contributo para a
identificação de tendências e de metodologias para reduzir a incerteza na gestão de empresas e redacções, procurando oferecer aquilo que, mais à frente, definimos enquanto uma “tecnologia de racionalidade”.
É um estudo híbrido quanto à sua forma e conteúdos. Híbrido entre a dimensão de investigação universitária e a prestação de serviços de consultoria, e que não esconde o objectivo, por entender ser na construção dessas pontes que pode produzir mais-valias para o sector da comunicação social em Portugal.info:eu-repo/semantics/publishedVersio
Immunogenicity of viral vaccines in the italian military
Military personnel of all armed forces receive multiple vaccinations and have been doing so since long ago, but relatively few studies have investigated the possible negative or positive interference of simultaneous vaccinations. As a contribution to fill this gap, we analyzed the response to the live trivalent measles/mumps/rubella (MMR), the inactivated hepatitis A virus (HAV), the inactivated trivalent polio, and the trivalent subunits influenza vaccines in two cohorts of Italian military personnel. The first cohort was represented by 108 students from military schools and the second by 72 soldiers engaged in a nine-month mission abroad. MMR and HAV vaccines had never been administered before, whereas inactivated polio was administered to adults primed at infancy with a live trivalent oral polio vaccine. Accordingly, nearly all subjects had baseline antibodies to polio types 1 and 3, but unexpectedly, anti-measles/-mumps/-rubella antibodies were present in 82%, 82%, and 73.5% of subjects, respectively (43% for all of the antigens). Finally, anti-HAV antibodies were detectable in 14% and anti-influenza (H1/H3/B) in 18% of the study population. At mine months post-vaccination, 92% of subjects had protective antibody levels for all MMR antigens, 96% for HAV, 69% for the three influenza antigens, and 100% for polio types 1 and 3. An inverse relationship between baseline and post-vaccination antibody levels was noticed with all the vaccines. An excellent vaccine immunogenicity, a calculated long antibody persistence, and apparent lack of vaccine interference were observed
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