2,249 research outputs found
The influence of the impedance function on gravity-based active accessibility measures: a comparative analysis applied to portuguese medium-sized cities
Active accessibility: A review of operational measures of walking and cycling accessibility
Active travel is enthusiastically promoted in the Westernworld due to its clear and demonstrated individual and collective benefits. While active travel has been shown to be associated with featuresof the built environment such as density and land-use mix, it is alsoassociated with walking and cycling accessibility-which we designateas active accessibility. However, the measurement of active accessibility is not straightforward and it can represent significantly differentfeatures of the built environment. This paper presents an extensivereview of published research that measures active accessibility. Weclassified the literature into four categories based on the methodologyused: distance-based, gravity-based or potential, topological or infrastructure-based, and walkability and walk score-type measures. A fifthcategory was created to classify outliers consisting of distinct methodological approaches or hybrids of the four main categories. We arguethat almost all of these methods have conceptual and computationallimitations, and that there are inconsistencies in the use of conceptsand terms. Furthermore, no sensitivity analysis was carried out on theselected parameters. We conclude by presenting some guidelines thatmight improve the value and clarity of active accessibility research,theory, and practice
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Annular Lichen Planus in Association with Crohn Disease
BACKGROUND: Lichen planus is an idiopathic inflammatory disease of the skin and mucous membranes. Although the etiology is not established, it has been associated with autoimmune diseases, viral infections, drugs and dental restoration materials. However, the association with inflammatory bowel disease has been very rarely reported in the literature.
CASE REPORT: A 19-year-old female patient presented with annular lesions on her upper body and limbs, with a sharply defined border and non-atrophic skin in the center. The lesions were hyperpigmented and had been stable for over one year. The histopathology confirmed the diagnosis of annular lichen planus. She had weight loss, occasional diarrhea, and a severe anemia. The investigation of these symptoms led to the diagnosis of Crohn disease and a sickle cell trait. Therapy with systemic corticosteroids and mesalazine controlled the intestinal disease, with concomitant improvement of the skin lesions.
CONCLUSIONS: As lichen planus can be associated with other immunological disorders, the association with inflammatory bowel disease should be considered in the evaluation of the patient
Learning about safety, prevention and quality of life through PBL: implications for teacher education
In Problem-Based Learning (PBL) students learn ‘new’ knowledge by solving problems. Studies focusing on the efficacy of PBL for the learning science content knowledge are rare and their results are not fully consistent. This study aims at: comparing the effectiveness of a transdisciplinary PBL and traditional teaching with regard to students’ learning of science knowledge within the scope of the theme Safety, Prevention and Quality of Life; finding out students’ opinions on transdisciplinary PBL approach. The sample is made of two 9th grade classes of a school located in the north of Portugal. The experimental class (24 students) approached the theme through PBL in an integrated way that is, Natural Sciences and Physical Sciences teachers pooled together the concepts that they were supposed to teach and organized PBL oriented teaching as if those concepts belonged to a single school subject. The control class (25 students) studied the same theme through traditional teaching, with the concepts of each school subject addressed separately by each one of the teachers. Data relative to content learning were collected by means of a pre- and a post-test and data relative to PBL students’ opinions on the new teaching approach were collected through an opinion questionnaire. Results indicate that transdisciplinary PBL led to a bit better results than traditional teaching and that students valued PBL.ERDF -European Regional Development Fund(PTDC/CPE-CED/108197/2008)info:eu-repo/semantics/publishedVersio
Elevated neopterin levels in non-allergic asthma
Neopterin is synthesized by human monocyte-derived macrophages upon stimulation with interferon-gamma (IFN-gamma). Measurement of neopterin concentration is useful to monitor cell-mediated (Th1-type) immune activation. In this study, we aimed to analyze the behaviour of neopterin in long lasting asthma considering its role as a marker of the Th1 environment and to establish the distinction between patients belonging either to the allergic or the non-allergic population, particularly in the elderly where asthma is often under diagnosed. Therefore we evaluated allergic parameters such as skin prick tests, IgE and hemogram (eosinophils count), and we compared our findings with neopterin values found in an age-matched control population. A group of individuals older than 65 was selected. It included 64 asthmatic patients (mean age 72+/-5 years) and 41 healthy individuals (mean age 79+/-7 years). In our study population, 42 patients presented positive skin tests, mainly to house dust mites. All patients were clinically stable and presented an average percentage of predicted forced expiratory volume in the first second (FEV1) of 73.6+/-25.3 and predicted median expiratory flow percentage (MEF50) of 38.8+/-26.7. Blood cell counts showed statistically different mean values of eosinophils between allergic and non-allergic controls (5.42+/-4.7% versus 2.8+/-2.8%; p2.1ng/ml) presented lower mean IgE values (IgE</=336.58IU) than those with lower neopterin values (</=2.1ng/ml) who presented mean IgE values of 402.70IU. Our initial findings may lead to a better understanding of the immunoinflammatory pathways in asthma. Further studies will probably show that serum neopterin could became a useful marker for asthma classification including in elderly patients with long lasting disease
Substance P in Long-Lasting Asthma: Immunoinflammatory pathways
Background: Substance P (SP) was described at the beginning of the 20th Century, and its biological action was recognized to have implications in neurogenic inflammation and constriction of smooth muscles. The changes associated with inflammatory chronicity can compromise organ function reversibility. The role of neuromechanisms in the pathology of the disease has been investigated in order to achieve better diagnosis and therapeutic approaches. The stimulation of human cells, such as macrophages and polymorphonuclear cells by SP leads to their activation and to the release of reactive oxygen species (ROS) by these cells. Consequently, a continuous inflammatory disability is observed, mainly if a decrease in antioxidant defence occurs. SP is a substrate for dipeptidyl peptidase IV (DPPIV), which is a multifunctional molecule with enzymatic and proinflammatory activities. CD26 is considered an activation T cell marker. The aim of the present study was to analyse if serum SP values in long-lasting asthma patients were related to lung function parameters. It was also decided to analyze the relationship of SP with superoxide dismutase (SOD) and total antioxidant activity in serum (TAS), as well as its association to CD26/DPPIV values considering their immunological and inflammatory properties. Methods/Data base: A group of individuals older than 65 years, including 64 asthmatic patients (mean age 72±5 years) and 41 healthy individuals (mean age 79±7years) was selected. Both subgroups were submitted to clinical observation, to skin prick tests (SPT) and to SP, TAS, SOD, and DPPIV determinations. T cell CD26 typing was also performed. Lung function tests were done on all patients. Results: Among the patients studied, 42 had positive skin tests, mainly to house dust mites. Asthmatic patients showed a significant increase in SP values (116.2±138.9 vs 39.5±17.9 pg/ml) when compared to controls and a significant decrease in TAS levels (.85±.13 vs .91±.10 mM) and in SOD levels (588.1±156.l vs 822.9±179.5 U/gHb). All patients were clinically stable and presented an average percentage of predict forced expiratory volume in the first second (FEV1) of 73.6±25.3 and median expiratory flow percentage of predict (MEF50) of 38.8±26.7. DPPIV values were significantly increased in asthmatics compared to controls (69.7±15.2 vs 58.6±14.3 U/L). The CD26 expression was only slightly increased in asthmatic patients (41.9±10.2 vs 39.4±11.4). Conclusion: These results confirm the role of SP in asthma and give a contribution for a better knowledge of the immunoinflammatory pathway associated with this chronic disorder. A final goal for these studies would be to achieve a better therapeutic approach in order to improve the outcome of asthmatic patients
The Deformable Mirror Demonstration Mission (DeMi) CubeSat: optomechanical design validation and laboratory calibration
Coronagraphs on future space telescopes will require precise wavefront
correction to detect Earth-like exoplanets near their host stars. High-actuator
count microelectromechanical system (MEMS) deformable mirrors provide wavefront
control with low size, weight, and power. The Deformable Mirror Demonstration
Mission (DeMi) payload will demonstrate a 140 actuator MEMS deformable mirror
(DM) with \SI{5.5}{\micro\meter} maximum stroke. We present the flight
optomechanical design, lab tests of the flight wavefront sensor and wavefront
reconstructor, and simulations of closed-loop control of wavefront aberrations.
We also present the compact flight DM controller, capable of driving up to 192
actuator channels at 0-250V with 14-bit resolution. Two embedded Raspberry Pi 3
compute modules are used for task management and wavefront reconstruction. The
spacecraft is a 6U CubeSat (30 cm x 20 cm x 10 cm) and launch is planned for
2019.Comment: 15 pages, 10 figues. Presented at SPIE Astronomical Telescopes +
Instrumentation, Austin, Texas, US
Association between calcium intake and body fat among pre-school Portuguese children
Obesity is the condition in which abnormally large body fat mass accumulates and causes a broad range of health problems. Some studies with children have reported an inverse asso ciation between dietary calcium intake and adiposity.info:eu-repo/semantics/publishedVersio
Substance P in Bronchial Asthma: Role in oxidant stress and in cell activation
The substance P (SP) was described in the beginning of the XXth Century, and its biological actions was recognized to have implications in neurogenic inflammation and constriction of smooth muscles. The bronchial asthma prevalence has been increasing in all developed countries. The changes associated to inflammatory chronicity can compromise the organ function reversibility. The role of neuromechanisms in the pathology of the disease has been investigated considering the hypotheses that better therapeutic approaches can be achieved. The stimulation of human cells by SP leads to their activation and to reactive oxygen species (ROS) release. Consequently a persisting inflammatory disability is observed, mainly if a decrease in the anti-oxidant defence occurs. SP is a substrate for dipeptidyl peptidase IV (DPPIV), which is a multifunctional molecule with enzymatic and proinflammatory activities. CD26 was identified as the membrane DPPIV and is considered as an activation T cell marker, as well as CD25. The aim of the present study was therefore to analyse if serum SP values in long-term asthma patients, were associated to lung function parameters, considering the role of SP in neurogenic inflammation and in bronchoconstriction. It was also proposed to analyse the relationship of SP with superoxide dismutase (SOD) and total anti-oxidation activity in serum (TAS), considering the ROS production during the inflammatory process, as well as its association to CD26 and CD25 values and their immunologic and inflammatory properties. A group of individuals older than 65 years including 64 asthmatic patients (mean age 72.4±5.1 years) and 41 healthy individuals (mean age 79.2±7.0 years) was selected. Both subgroups were submitted to clinical observation, to skin prick tests and to SP, TAS and SOD. T cell CD26 and CD25 typing was also performed. Lung function tests were done to all patients. Among patients studied, 42 presented positive skin tests, mainly to house dust mites. Asthmatic patients presented significant increased values of SP (116.2±138.9 vs 39.5±17.9 pg/ml) when compared to controls and a significant decrease of TAS (.85±.13 vs .91±.10 mM) and SOD (588.1±156.l vs 822.9±179.5 U/gHb). All patients have clinical stability and presented forced expiratory volume in one second (FEV1) values of 73.6±25.3 l/s and peak expiratory flow (PEF50) of 38.8±26.7l. The CD25 expression was significantly increased in disease (14.3±5.9 vs 22.4±7.8) while CD26 was only slightly increased (41.9±10.2 vs 39.4±11.4). These results confirm the role of SP in the respiratory pathology studied and give a contribution for a better knowledge of the network of immunoinflammatory pathway, associated to this chronic disorder. A final goal for these studies would be a better diagnostic and therapeutic approach in this pathology
Identificação de raças fisiológicas de Hemileia vstatrix Berk. & Br. no Estado do Espírito Santo, Brasil.
Cento e trinta e nove isolados de Hemileia vastatrix foram coletados de plantas de cultivares de Coffea canephora e Coffea arabica, nos estados do Espírito Santo e Minas Gerais. Os isolados foram inoculados em plantas do cultivar Catuaí Vermelho LCH 2077-2-5-44 em condição de casa de vegetação, de junho de 1995 a julho de 1997. A identificação de raças foi acompanhada pela inoculação de isolados de H. vastatrix em clones diferenciadores, mantidos em casa de vegetação no Departamento de Fitopatologia da Universidade Federal de Viçosa. Raças de H. vastatrix foram determinada segundo D’Oliveira (1954, 1957). A raça II foi identificada em todos os 96 isolados de C. canephora do estado do Espírito Santo
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