553 research outputs found
Imagery and long-slit spectroscopy of the Polar-Ring Galaxy AM2020-504
Interactions between galaxies are very common. There are special kinds of
interactions that produce systems called Polar Ring Galaxies (PRGs), composed
by a lenticular, elliptical, or spiral host galaxy, surrounded by a ring of
stars and gas, orbiting in an approximately polar plane. The present work aims
to study AM2020-504, a PRG with an elliptical host galaxy, and a narrow and
well defined ring, probably formed by accretion of material from a donor
galaxy, collected by the host galaxy. Our observational study was based on BVRI
broad band imagery as well as longslit spectroscopy in the wavelenght range
4100--8600\AA, performed at the 1.6m telescope at the Observat\'orio do Pico
dos Dias (OPD), Brazil. We estimated a redshift of z= 0.01683, corresponding a
heliocentric radial velocity of 5045 +/-23 km/s. The (B-R) color map shows that
the ring is bluer than the host galaxy, indicating that the ring is a younger
structure. Standard diagnostic diagrams were used to classify the main ionizing
source of selected emission-line regions (nucleus, host galaxy and ring). It
turns out that the ring regions are mainly ionized by massive stars while the
nucleus presents AGN characteristics. Using two empirical methods, we found
oxygen abundances for the HII regions located in the ring in the range
12+log(O/H)=8.3-8.8 dex, the presence of an oxygen gradient across the ring,
and that AM2020-504 follows the metallicity-luminosity relation of spiral
galaxies. These results support the accretion scenario for this object and
rules out cold accretion as source for the HI gas in the polar ring
Adult mastocytosis: a review of the Santo António Hospital 's experience and an evaluation of World Health Organization criteria for the diagnosis of systemic disease
BACKGROUND:
Mastocytosis is a clonal disorder characterized by the accumulation of abnormal mast cells in the skin and/or in extracutaneous organs.
OBJECTIVES:
To present all cases of mastocytosis seen in the Porto Hospital Center and evaluate the performance of World Health Organization diagnostic criteria for systemic disease.
METHODS:
The cases of twenty-four adult patients with mastocytosis were reviewed. Their clinical and laboratorial characteristics were assessed, and the properties of the criteria used to diagnose systemic mastocytosis were evaluated.
RESULTS:
The age of disease onset ranged from 2 to 75 years. Twenty-three patients had cutaneous involvement and 75% were referred by dermatologists. Urticaria pigmentosa was the most common manifestation of the disease. One patient with severe systemic mast cell mediator-related symptoms showed the activating V560G KIT mutation. The bone marrow was examined in 79% of patients, and mast cell immunophenotyping was performed in 67% of the participants. Systemic disease was detected in 84% of cases, and 81% of the sample had elevated serum tryptase levels. All the diagnostic criteria for systemic mastocytosis had high specificity and positive predictive value. Bone marrow biopsy had the lowest sensitivity, negative predictive value and efficiency, while the highest such values were observed for mast cell immunophenotyping. Patients were treated with regimens including antihistamines, sodium cromoglycate, alpha-interferon, hydroxyurea and phototherapy.
CONCLUSIONS:
Cutaneous involvement is often seen in adult mastocytosis patients, with most individuals presenting with indolent systemic disease. Although serum tryptase levels are a good indicator of mast cell burden, bone marrow biopsy should also be performed in patients with normal serum tryptase, with flow cytometry being the most adequate method to diagnose systemic disease
Dax1 modulates ERα-dependent hypothalamic estrogen sensing in female mice
Coupling the release of pituitary hormones to the developmental stage of the oocyte is essential for female fertility. It requires estrogen to restrain kisspeptin (KISS1)-neuron pulsatility in the arcuate hypothalamic nucleus, while also exerting a surge-like effect on KISS1-neuron activity in the AVPV hypothalamic nucleus. However, a mechanistic basis for this region-specific effect has remained elusive. Our genomic analysis in female mice demonstrate that some processes, such as restraint of KISS1-neuron activity in the arcuate nucleus, may be explained by region-specific estrogen receptor alpha (ERα) DNA binding at gene regulatory regions. Furthermore, we find that the Kiss1-locus is uniquely regulated in these hypothalamic nuclei, and that the nuclear receptor co-repressor NR0B1 (DAX1) restrains its transcription specifically in the arcuate nucleus. These studies provide mechanistic insight into how ER may control the KISS1-neuron, and Kiss1 gene expression, to couple gonadotropin release to the developmental stage of the oocyte
Reduzindo o efeito da radiação ultravioleta sobre leveduras para o controle de podridões pós-colheita de frutas.
O objetivo deste trabalho foi avaliar a suscetibilidade natural de isolados promissores de levedura e selecionar fotoprotetores com potencial de uso em futuras formulaçõe
Fixação biológica de nitrogênio em agroecossistemas da região Semiárida do Nordeste.
A fixação biológica de nitrogênio (FBN) é um processo natural conduzido por um conjunto de procariotos que apresentam a capacidade de reduzir o N2 atmosférico à amônia, uma das formas assimiláveis pelas plantas; é considerado o segundo processo biológico mais importante da natureza, atrás apenas da fotossíntese (Moreira; Siqueira, 2006). Pelas suas características, esse é o principal processo de entrada de nitrogênio (N) nas cadeias alimentares, o que ressalta a importância ecológica desse processo nos ambientes naturais
Maker Club in Pre-School
The project allows pre-school children to develop the problematization of what they are learning and, in secondary school, students’ perspectives of cooperative in the development of scientific literacy. In this type of activity, children, with the help of high school students, deepen and consolidate behavioral values for life, thus enabling a positive change in their attitudes, in the way of believing, innovating, planning and persisting to conquer. Theactivities developed are accessible, both in approach and availability as well as in the cost of materials
Functionalized asphalt mixtures: Photocatalytic, superhydrophobic and self-cleaning properties
Functionalization of road pavement asphalt mixtures provides new capabilities that can mitigate problems like air pollution and road accidents. In this research, nano-TiO2 and micro-ZnO were deposited through an aqueous solution by spraying it over the surface of asphalt mixture samples in order to promote the photocatalytic, superhydrophobic and self-cleaning capabilities. Tested by degradation of Rhodamine B, to assess the Photocatalytic Efficiency, and by Water Contact Angle (WCA), to assess the wettability of the materials, this technique can be used to promote these multifunctional capabilities in asphalt mixtures. With these enhanced surface characteristics, road safety and the environment, through pollutants degradation like NOx and SO2, will be improved.This work was supported by FCT—Fundação para a Ciência e Tecnologia—through the project
PEst-OE/ECI/UI4047/2014info:eu-repo/semantics/publishedVersio
Resistance training practices of Brazilian Olympic sprint and jump coaches: toward a deeper understanding of their choices and insights (part III)
In the final part of this three-article collection on the training strategies of Brazilian Olympic sprint and jump coaches, we provide a detailed description of the resistance training methods and exercises most commonly employed by these speed experts. Always with the objective of maximizing the sprint and jump capabilities of their athletes, these experienced coaches primarily utilize variable, eccentric, concentric, machine-based, isometric, complex, and isoinertial resistance training methods in their daily practices. Squats (in their different forms), Olympic weightlifting, ballistics, hip thrusts, lunges, calf raises, core exercises, leg curls, stiff-leg deadlifts, and leg extension are the most commonly prescribed exercises in their training programs, during both the preparatory and competitive periods. Therefore, the current manuscript comprehensively describes and examines these methods, with the additional aim of extrapolating their application to other sports, especially those where sprint speed is a key performance factor
Pain and analgesia in critical illness
A detecção, quantificação e tratamento da dor em doente crítico é, à longa data, uma preocupação dos clínicos que tra-
balham em Unidades de Cuidados Intensivos. Não obstante, a dor é frequente em doentes críticos, independentemente do
seu critério de admissão.
Os autores apresentam uma revisão sobre analgesia em doente critico enfatizando o recurso a escalas apropriadas para o
seu diagnóstico, quantificação e avaliação de terapêuticas efetuadas. São descritas as abordagens farmacológicas (sistémicas
e regionais) recomendadas e discute-se a evolução do evento doloroso agudo a crónico em contexto de cuidados intensivos
Reduzindo o efeito da radiação ultravioleta sobre leveduras para o controle de podridões pós-colheita de frutas.
O objetivo deste trabalho foi avaliar a suscetibilidade natural de isolados promissores de levedura e selecionar fotoprotetores com potencial de uso em futuras formulações
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