262 research outputs found
Benchmarking some Portuguese S&T system research units: 2nd Edition
The increasing use of productivity and impact metrics for evaluation and
comparison, not only of individual researchers but also of institutions,
universities and even countries, has prompted the development of bibliometrics.
Currently, metrics are becoming widely accepted as an easy and balanced way to
assist the peer review and evaluation of scientists and/or research units,
provided they have adequate precision and recall.
This paper presents a benchmarking study of a selected list of representative
Portuguese research units, based on a fairly complete set of parameters:
bibliometric parameters, number of competitive projects and number of PhDs
produced. The study aimed at collecting productivity and impact data from the
selected research units in comparable conditions i.e., using objective metrics
based on public information, retrievable on-line and/or from official sources
and thus verifiable and repeatable. The study has thus focused on the activity
of the 2003-06 period, where such data was available from the latest official
evaluation.
The main advantage of our study was the application of automatic tools,
achieving relevant results at a reduced cost. Moreover, the results over the
selected units suggest that this kind of analyses will be very useful to
benchmark scientific productivity and impact, and assist peer review.Comment: 26 pages, 20 figures F. Couto, D. Faria, B. Tavares, P.
Gon\c{c}alves, and P. Verissimo, Benchmarking some portuguese S\&T system
research units: 2nd edition, DI/FCUL TR 13-03, Department of Informatics,
University of Lisbon, February 201
Effect of exercise training on lymphocyte subpopulations in chemically and hormonally induced prostate cancer: flow cytometry analysis
Introduction: Long-term and regular exercise training is suggested to have an immunomodulatory effect, protecting against several diseases. This work aimed to analyse the effect of exercise training on peripheral lymphocyte subpopulations in a model of prostate cancer (PCa) chemically and hormonally induced.
Methods: Fifty-five male Wistar Unilever rats of 4 weeks of age were randomly divided into four experimental groups as follow: control sedentary group (SED+CONT; n=10), control exercised group (EX+CONT; n=10), induced sedentary group (SED+PCa; n=15) and induced exercised group (EX+PCa; n=20). Prostate lesions were induced through the sequential administration of flutamide (50 mg/kg, TCI Chemicals, USA), testosterone propionate (100 mg/kg, TCI Chemicals, Portland, USA) and N-methyl-N-nitrosourea (30 mg/kg, Sigma Chemical, Spain), and subcutaneous implantation of tubes filled with crystalline testosterone (Sigma Chemical, Spain). At eight weeks of age, exercised animals started the training in a treadmill (Treadmill Control LE 8710, USA), 5 days/weeks, for 53 weeks. Animals were sacrificed at 61 weeks of age through an intraperitoneal injection of ketamine (75 mg/kg, Imalgene® 1000, Merial S.A.S., France) and xylazine (10 mg/kg, Rompun® 2%, Bayer Healthcare S.A., Germany), followed by exsanguination by cardiac puncture. Peripheral blood of all animals was collected by intracardiac puncture and transferred into tubes containing EDTA salt as an anticoagulant for flow cytometry analysis. The following conjugated monoclonal antibodies were used: cyCD3-BV421, CD3-FITC, CD25-APC, CD45-BV510, CD127-PE, CD161-FITC, CD4-PE/Cy7, CD45RA-APC/Cy7, OX-82-PE and CD8a-PerCP. The flow cytometry immunophenotyping was performed in a BD FACSCantoTM II cytometer (BD Biosciences, USA) and data were analysed with InfinicytTM, flow cytometry software 1.7 version. The prostate was collected and stained with H&E for histopathological analysis. Statistical analysis was performed using SPSS 25. The differences were considered statistically significant at p<0.05.
Results: A higher level of CD161+NK cells were observed in EX+PCa group when compared with SED+PCa group (p0.05).
Conclusion: These results reinforce the beneficial role of exercise in anti-tumour immune response. Additional studies are warranted to better understand these results
Analysis of Freight Trip Generation Model for Food and Beverage in Belo Horizonte (Brazil)
Today, one of the main challenges faced in urban logistics is the distribution of goods. In Brazil, mid to large cities have experienced consequences of unplanned urban sprawl and lack of adequate transportation infrastructure. The relationship between urban planning and transport stands out the attractiveness of some urban activities with direct impacts on the movement of people and goods and other component elements of urban space. The segment of bars and restaurants falls within this context, therefore is a vital activity responsible for significant percentage of jobs and revenue in a city. Altogether, foods & beverages commercial activities move daily large volumes of goods to meet the need of customers. This paper presents the results of a freight trip generation model developed for pubs and restaurants in Belo Horizonte (Brazil). Once performed the model determined the number of trips generated per day per establishment. In order to expand the discrete result to a continuous one, the results were geographically interpolated to a continuous surface and extrapolated within the city limits. The data for the freight trip generation model were obtained by survey. For this, we designed a structured questionnaire to obtain information about goods, frequency, operational time, place of performance of the loading/unloading of goods, establishment size and the number of employees. Besides these information, we investigated the acceptance of alternative practices in the delivery of goods, such as off-peak delivery. To accomplish the proposed models, we applied a simple linear regression, correlating the following variables: (i) Number of trips versus area of the establishment; (ii) Number of trips versus number of employees; (iii) Number of trips versus operation day of the establishment. With the results of the linear regression for travel generations, conducted the data interpolation based on the standard deviation of the results to define the sample classification bands. This interpolation method was chosen because it is one of the most suitable for analysis of spatially scattered points due to the straightforwardness of the model and because it does not consider extra noise such as slope and spatial constraints as barriers. In this method, interpolation is determined by the value assigned to each point (in this case the number of trips), wherein the closer the points the higher the correlation trend. Finally, the resulting trip generation surface was analysed together with other geographic data such as demographic data, road network density and socioeconomic data. Findings indicate the importance of a mathematic-geographic model for trip generation as a feasible approach for support transportation planning & operation for urban goods distribution. Critical information such as the high concentration of pubs and restaurants in the same region can reinforce the vocation of the city for trading. However, an elevated number of freight vehicles to meet a high and growing demand becomes a problem specially in areas where urban road network is not efficient (not properly designed and parking spaces not properly used). This study also highlights the need for an urban freight mobility plan and public policies, by offering sustainable alternatives for urban goods distribution, which improve the urban environment. By using geospatial analysis, the study delivered statistics data and maps to catch the attention of decision makers and transportation managers, therefore facilitate the discussion on transportation policies in the city of Belo Horizonte
Effects of physical exercise in biochemical parameters and dorsolateral prostate lesions: data from a rat model of prostate cancer
Background: Prostate cancer (PCa) is among the most prevalent cancers worldwide. Physical exercise is widely recognized due to its beneficial effects. This study aimed to evaluate the effects of physical exercise on biochemical pa- rameters and in dorsolateral prostate lesions in a rat model of PCa.
Materials and Methods: Ninety-five male Wistar Unilever rats were randomly divided into eight groups sacrificed at 35 (groups I) or 61 weeks of age (groups II): control sedentary groups (Cont+Sed I (n = 10); Cont+Sed II (n = 10)); induced sedentary group (PCa+Sed I (n = 10); PCa+Sed II (n = 15)); control exercised groups (Cont+EX I (n = 10); Cont+EX II(n = 10)) and induced exercised groups (PCa+EX I (n = 10); PCa+EX II (n = 20)). All procedures were approved (DGAV, no. 021326). Animals from exercised groups started the exer- cise program in a treadmill at 8 weeks of age, for 28 weeks or 53 weeks. The animals were trained 5 days/week, 60 min per day. Prostate lesions were induced at 12 weeks of age, with sequential administration of flutamide, testosterone propion- ate and N-methyl-N-nitrosourea, and subcutaneous implants of crystalline testosterone. Animals were sacrificed at 35 or 61 weeks of age. Peripheral blood of all animals was col- lected by intracardiac puncture. A complete necropsy was performed. The dorsolateral prostate tissues sections were processed for histological analysis. Data were analysed using SPSS 25. p 0.05). Dorsolateral prostate lesions were classified as dysplasia, prostatic intraep- ithelial neoplasia (PIN) and microinvasive carcinoma. The number of prostate lesions was higher in animals from groups II than in those from groups I, mainly in PCa+Sed II animals when compared with PCa+Sed I (p 0.05).
Conclusions: Overall, the animals sacrificed at 61 weeks of age developed more dorsolateral prostate lesions than ani- mals sacrificed at 35 weeks of age, which may be related to a longer testosterone exposure
Physical exercise in a chemically and hormonally induced rat model of prostate cancer: friend or foe?
Introduction: Physical exercise is widely recognized for its beneficial health effects, namely in prostate cancer (PCa). This study aimed to evaluate the effect of physical exercise in a rat model of chemically and hormonally induced PCa.Results: Body weight was lower in exercised groups than in sedentary, either in control or in PCa groups (p0.05) and animals from PCa-exercised group showed 70.0% of dysplasia, 58.8% of PIN and 58.8% of microinvasive carcinoma (p>0.05). Conclusions: No group showed systemic signs of inflammation or clinical abnormalities. Although the prostate lesions frequencies were slightly lower in exercised PCa-induced animals than in sedentary ones, data didn ́t achieve statistical significance. However, our results suggest that physical exercise may have some preventive effect on the PCa-lesion’s development. These data deserve more investigation to clarify the effect of exercise training on prostate cancer prevention
Evaluation of push and pull communication models on a VANET with virtual traffic lights
It is expected in a near future that safety applications based on vehicle-to-everything communications will be a common reality in the traffic roads. This technology will contribute to improve the safety of vulnerable road users, for example, with the use of virtual traffic light systems (VTLS) in the intersections. This work implements and evaluates a VTLS conceived to help the pedestrians pass safely the intersections without real traffic lights. The simulated VTLS scenario used two distinct communication paradigms—the pull and push communication models. The pull model was implemented in named data networking (NDN), because NDN uses natively a pull-based communication model, where consumers send requests to pull the contents from the provider. A distinct approach is followed by the push-based model, where consumers subscribe previously the information, and then the producers distribute the available information to those consumers. Comparing the performance of the push and pull models on a VANET with VTLS, it is observed that the push mode presents lower packet loss and generates fewer packets, and consequently occupies less bandwidth, than the pull mode. In fact, for the considered metrics, the VTLS implemented with the pull mode presents no advantage when compared with the push mode.This work has been supported by national funds through FCT—Fundação para a Ciência e Tecnologia
within the Project Scope: UID/CEC/00319/2020 and by the European Structural and Investment Funds in the
FEDER component, through the Operational Competitiveness and Internationalization Programme (COMPETE
2020) [Project nº 039334; Funding Reference: POCI-01-0247-FEDER-039334]
A new approach on communications architectures for intelligent transportation systems
A Vehicular Adhoc Network (VANET) is a generic communications conceptualization that can be applied to Intelligent Transportation Systems (ITS) and its main goal is to allow exchange of information between moving vehicles, fixed infrastructures, pedestrians with personal devices, and all other electronic devices able to connect to a VANET environment. Information exchange between different stakeholders brings a relevant potential to the development of applications to help users in different areas such as traffic safety and efficiency, infotainment and personal comfort. However, due to the expected heterogeneity (different processing power and storage capabilities, communications technologies and mobility patterns) and large scale on the number of devices involved, application interoperability in VANET contexts can be a challenging problem. Non-agnostic standard communications architectures for ITS systems have some deploying limitations and lack important specific implementation details. This paper presents an agnostic VANET architecture (it permits the use of several communication technologies in an open and modular framework), which is an adaption of present standards approach, to be deployed on ITS systems as a mean to overcome their main limitations. (C) 2017 The Authors. Published by Elsevier B.V.This work has been sponsored by the Portugal Incentive System for Research and Technological Development. Project in co-promotion no 002797/2015 (INNOVCAR 2015-2018), and also by COMPETE: POCI-01-0145-FEDER-007043 and FCT - Fundação para a Ciência e Tecnologia within the Project Scope: UID/CEC/00319/2013
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