478 research outputs found

    Distribution patterns and indicators of the smooth hammerhead shark (Sphyrna zygaena) in the Atlantic Ocean

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    The smooth hammerhead shark, Sphyrna zygaena, is a pelagic shark occasionally captured as bycatch by industrial pelagic longline fleets in the Atlantic Ocean. Data for this study were collected by fishery observers, between 2003 and 2016. Datasets analyzed included information on catches per unit effort (CPUE), size and sex of smooth hammerhead sharks bycaught by the Portuguese pelagic longline fishery in the Atlantic Ocean. A total effort of 2 523 288 hooks yielded 638 sharks, ranging in size from 123 to 275 cm fork length. Larger sharks tended to occur in open ocean habitats and smaller specimens in coastal areas. Results confirmed the wide latitudinal range of the species (45 degrees N-35 degrees S), although CPUE was higher closer inshore within the Tropical North and Equatorial regions. An overall sex ratio of 1.4 males for each female was observed, with more males in both inshore and offshore waters. Significant differences in CPUE and size distribution were found between regions, years and quarters of the year. Mean CPUE increased and mean specimen size decreased in the Equatorial region from 2012 onwards. In order to remove fishery-dependent effects from CPUE data, a Tweedie Generalized Linear Model (GLM) was used to create a relative index of abundance (standardized CPUE). The index showed some oscillations in the initial years (2008-2010), followed by a decreasing trend until 2013 and then an increasing trend in more recent years, until 2016. The distributional patterns and indicators presented in this study provide a better understanding of the smooth hammerhead shark's spatio-temporal dynamics and population structure in the Atlantic Ocean and can be used to improve management and conservation measures for this species.AgĂȘncia financiadora Programa Nacional de Amostragem Biologica (PNAB) within the EU Data Collection Framework (DCF) Project "SHARK-TAG: Migrations and habitat use of the smooth hammerhead shark in the Atlantic Ocean" Oceanario de Lisboa Investigator-FCT contract from the Portuguese Foundation for Science and Technology (FCT, Fundacao para a Ciencia e Tecnologia) - EU European Social Fund IF/00253/2014 Programa Operacional Potencial Humanoinfo:eu-repo/semantics/publishedVersio

    Performance Tiers within a Competitive Age Group of Young Swimmers Are Characterized by Different Kinetic and Kinematic Behaviors

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    The present study aimed to analyze swimmers’ in-water kinetic and kinematic behaviors according to different swimming performance tiers within the same age group. An amount of 53 highly trained swimmers (girls and boys: 12.40 ± 0.74 years) were split up into 3 tiers based on their personal best performance (i.e., speed) in the 50 m freestyle event (short-course): lower-tier (1.25 ± 0.08 m·s−1); mid-tier (1.45 ± 0.04 m·s−1); and top-tier (1.60 ± 0.04 m·s−1). The in-water mean peak force was measured during a maximum bout of 25 m front crawl using a differential pressure sensors system (Aquanex system, Swimming Technology Research, Richmond, VA, USA) and defined as a kinetic variable, while speed, stroke rate, stroke length, and stroke index were retrieved and considered as kinematic measures. The top-tier swimmers were taller with a longer arm span and hand surface areas than the low-tier, but similar to the mid-tier. While the mean peak force, speed and efficiency differed among tiers, the stroke rate and stroke length showed mixed findings. Coaches should be aware that young swimmers belonging to the same age group may deliver different performance outcomes due to different kinetic and kinematic behaviors.Portuguese Foundation for Science and Technology (FCT),Grants 2020.08326.BD and UIDB04045/202

    Biomechanical responses to water fitness programmes: a narrative review

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    In the past years, there was an increasing interest in the biomechanical responses in water fitness sessions. The present review consolidates the current “state-of-art” on the biomechanical responses in water fitness programmes. The literature was searched and screened studies on: (i) healthy subjects; and (ii) water fitness sessions and programmes reporting physical condition outcomes. A total of 36 studies met the inclusion criteria and categorized into four categories: (i) kinematics (n = 5); (ii) ground reaction force (n = 10); (iii) neuromuscular (n = 8); and (iv) strength (n = 14). There was a larger amount of evidence on strength, whereas some gaps in the body of knowledge still persist in the remaining categories. The existent studies cover a large range of age brackets (from young adults to the elderly). Women were recruited more often than men to be part of the studies. The effect of music cadence, body segments, exercise type (e.g., alternated or simultaneous), water depth, resistance equipment, and training protocols were the main topics under research.info:eu-repo/semantics/publishedVersio

    Shoreline response to a sandy nourishment in a wave-dominated coast using video monitoring

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    PTDC/EAM-REM/30324/2017 UIDB/00308/2020 PTDC/EAM-OCE/31207/2017 PTDC/ECI-EGC/31090/2017 UID/MAR/04292/2019Beach nourishment is a soft engineering intervention that supplies sand to the shore, to increase the beach recreational area and to decrease coastal vulnerability to erosion. This study presents the preliminary evaluation of nourishment works performed at the high-energy wave-dominated Portuguese coast. The shoreline was adopted as a proxy to study beach evolution in response to nourishment and to wave forcing. To achieve this aim, images collected by a video monitoring system were used. A nourishment calendar was drawn up based on video screening, highlighting the different zones and phases where the works took place. Over the six-month monitoring period, a total amount of 25 video-derived shorelines were detected by both manual and automated procedures on video imagery. Nourishment works, realized in summer, enlarged the emerged beach extension by about 90mon average. During winter, the shoreline retreated about 50m due to wave forcing. Spatial analysis showed that the northern beach sector was more vulnerable and subject to erosion, as it is the downdrift side of the groin.publishersversionpublishe

    Molecular biomarkers associated with respiratory insufficiency in amyotrophic lateral sclerosis

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    Abstract in proceedings of the Fourth International Congress of CiiEM: Health, Well-Being and Ageing in the 21st Century, held at Egas Moniz’ University Campus in Monte de Caparica, Almada, from 3–5 June 2019.This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.info:eu-repo/semantics/publishedVersio

    A comparison of load cell and pressure sensors to measure in-water force in young competitive swimmers

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    The purpose of this study was to compare the in-water force of young competitive swimmers using tethered swimming and differential pressure sensors. Thirty-one swimmers (16 girls and 15 boys) were randomly assigned to perform two in-water tests. Swimmers completed two maximum bouts of 25 m front crawl with a differential pressure system and a 30 s maximum bout with an attached load cell (tethered-swimming). The peak force (FPEAK, in N) of dominant and non-dominant upper limbs was retrieved for further analysis. Comparison between methods revealed significant differences in all force variables (p ≀ 0.05) and the biases (mean differences) were large in girls (FPEAK dominant, 45.89 N; FPEAK non-dominant, 43.79 N) and boys (FPEAK dominant, 67.26 N; FPEAK non-dominant, 61.78 N). Despite that, simple linear regression models between the two methods showed significant relationships with a moderate effect in all variables for girls, whereas in boys a high and moderate effect was verified for FPEAK of dominant and non-dominant limbs (respectively). It seems that using pressure sensors and tethered swimming leads to different FPEAK values in young competitive, where correction factors are needed to compare data between both methods.The authors would like to thank all swimming coaches for their voluntary support as well as all the swimmers involved. This project was supported by the Portuguese Foundation for Science and Technology (FCT), I.P., under Grants 2020.08326.BD and UID 04045/2020.info:eu-repo/semantics/publishedVersio

    Mitochondrial Dynamics in the Drosophila Ovary Regulates Germ Stem Cell Number, Cell Fate, and Female Fertility

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    This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (H2020-ERC-2017-STGGA 759853-StemCellHabitat), Wellcome Trust and Howard Hughes Medical Institute (HHMI-208581/Z/17/Z-Metabolic Reg SC fate), EMBO Installation grant (H2020-EMBO3311/2017/G2017), and by Fundação para a CiĂȘncia e Tecnologia (IF/01265/2014/CP1252/CT0004 and PD/BD/128003/2016 to MG).The fate and proliferative capacity of stem cells have been shown to strongly depend on their metabolic state. Mitochondria are the powerhouses of the cell being responsible for energy production via oxidative phosphorylation (OxPhos) as well as for several other metabolic pathways. Mitochondrial activity strongly depends on their structural organization, with their size and shape being regulated by mitochondrial fusion and fission, a process known as mitochondrial dynamics. However, the significance of mitochondrial dynamics in the regulation of stem cell metabolism and fate remains elusive. Here, we characterize the role of mitochondria morphology in female germ stem cells (GSCs) and in their more differentiated lineage. Mitochondria are particularly important in the female GSC lineage. Not only do they provide these cells with their energy requirements to generate the oocyte but they are also the only mitochondria pool to be inherited by the offspring. We show that the undifferentiated GSCs predominantly have fissed mitochondria, whereas more differentiated germ cells have more fused mitochondria. By reducing the levels of mitochondrial dynamics regulators, we show that both fused and fissed mitochondria are required for the maintenance of a stable GSC pool. Surprisingly, we found that disrupting mitochondrial dynamics in the germline also strongly affects nurse cells morphology, impairing egg chamber development and female fertility. Interestingly, reducing the levels of key enzymes in the Tricarboxylic Acid Cycle (TCA), known to cause OxPhos reduction, also affects GSC number. This defect in GSC self-renewal capacity indicates that at least basal levels of TCA/OxPhos are required in GSCs. Our findings show that mitochondrial dynamics is essential for female GSC maintenance and female fertility, and that mitochondria fusion and fission events are dynamically regulated during GSC differentiation, possibly to modulate their metabolic profile.publishersversionpublishe

    A pilot study on the efficacy of a single intra-articular administration of Triamcinolone Acetonide, Hyaluronan, and a combination of both for clinical management of osteoarthritis in Police Working Dogs

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    Research Areas: Veterinary SciencesObjectives: To describe and compare the use and effectiveness of a single intra-articular injection (IA) of triamcinolone acetonide (TA), hyaluronan (HA), and a combination of both (TA+HA) in police working dogs with natural occurring hip osteoarthritis (OA). Study Design: Prospective, randomized, single-blinded study. Sample Population: Thirty animals with naturally occurring hip OA. Methods: Animals were randomly divided in three groups: GT, treated with 20 mg of TA per hip joint; GH, treated with treated 20 mg of HA per hip joint; and GTH, treated with a combination of 20 mg of TA and 20 mg of HA per hip joint. Response to treatment, measured by the Canine Brief Pain Inventory (divided in Pain Interference Score-PIS and Pain Severity Score-PSS) and the Hudson Visual Analog Scale (HVAS), was evaluated in seven different time points: T0 (before treatment), T1 (after 15 days), T2, T3, T4, T5, and T6 (after 1, 2, 3, 4, and 5 months, respectively). Results were compared using a Kruskal-Wallis test or a Wilcoxon signed ranks test, and p < 0.05 was set. Results: Comparing results of the different time points considered with T0, significant differences were registered in GH at T1 for HVAS (p = 0.03) and PIS (p = 0.04); and in GTH at T1 (p = 0.05 for HVAS and p = 1 for PSS or >= 2 for PIS. In GTH, treatment was successful in four animals between T1 and T5 (40%, n = 10) and three at T6-T7 (30%, n = 10) for PSS and three animals of GTH at T1 (30%), two at T2 (20%), three between T3 and T4 (30%), and two between T5 and T7 (20%)info:eu-repo/semantics/publishedVersio

    The effects of a transportation cost shock on firm performance and behavior

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    Funding Information: ☆ The authors are grateful to Kristian Behrens (the editor), two anonymous referees, Pedro Bação, Ronald Bachmann, Pedro Pita Barros, Samira Barzin, MĂĄrio Centeno, Joana Costa, Dave Donovan, Luisa Doerr, Ed Glaeser, Robert Gold, Nezih Guner, Julian Hinz, Adelheid Holl, Gabriel Kreindler, Xiang Li, Pedro Martins, Alejandro Micco, Yi Niu, Susana Peralta, Alfredo M Pereira, Miguel Portela, Pedro Portugal, Francisco QueirĂł, Lasare Samartzidis, Rok Spruk, and seminar participants at Nova SBE, the DUP meeting (Harvard University), the 3rd CompNet ProdTalks, SAEe2020, the 9th PhD Student Workshop on Industrial and Public Economics (ECO-SOS), the 10th European Meeting of the UEA, COMPIE 2021, the 14th Annual Meeting of the PEJ, EARIE 2021, Jornadas de Economia Industrial of the Spanish Economic Association, 11th ifo Dresden Workshop on Regional Economics, CAED 2021 (Coimbra), the 4th Meeting on Transport Economics and Infrastructure, the Fourth International Workshop “Market Studies and Spatial Economics”, the Spring Meeting for Young Economists (OrlĂ©ans), the 7th Linked Employer-Employee Data Workshop (FEP), and the 2022 SMU-Jinan Conference on Urban and Regional Economics for useful comments and suggestions. We would also like to thank BPLim – Banco de Portugal for providing the necessary data for this study and Nuno Afonso for excellent research assistance. This work was funded by Fundação para a CiĂȘncia e Tecnologia (UIDB/00124/2020, UIDP/00124/2020 and Social Sciences DataLab - PINFRA/22209/2016), POR Lisboa and POR Norte (Social Sciences DataLab, PINFRA/22209/2016). All errors are our own. Funding Information: The authors are grateful to Kristian Behrens (the editor), two anonymous referees, Pedro Bação, Ronald Bachmann, Pedro Pita Barros, Samira Barzin, MĂĄrio Centeno, Joana Costa, Dave Donovan, Luisa Doerr, Ed Glaeser, Robert Gold, Nezih Guner, Julian Hinz, Adelheid Holl, Gabriel Kreindler, Xiang Li, Pedro Martins, Alejandro Micco, Yi Niu, Susana Peralta, Alfredo M Pereira, Miguel Portela, Pedro Portugal, Francisco QueirĂł, Lasare Samartzidis, Rok Spruk, and seminar participants at Nova SBE, the DUP meeting (Harvard University), the 3rd CompNet ProdTalks, SAEe2020, the 9th PhD Student Workshop on Industrial and Public Economics (ECO-SOS), the 10th European Meeting of the UEA, COMPIE 2021, the 14th Annual Meeting of the PEJ, EARIE 2021, Jornadas de Economia Industrial of the Spanish Economic Association, 11th ifo Dresden Workshop on Regional Economics, CAED 2021 (Coimbra), the 4th Meeting on Transport Economics and Infrastructure, the Fourth International Workshop “Market Studies and Spatial Economics”, the Spring Meeting for Young Economists (OrlĂ©ans), the 7th Linked Employer-Employee Data Workshop (FEP), and the 2022 SMU-Jinan Conference on Urban and Regional Economics for useful comments and suggestions. We would also like to thank BPLim – Banco de Portugal for providing the necessary data for this study and Nuno Afonso for excellent research assistance. This work was funded by Fundação para a CiĂȘncia e Tecnologia (UIDB/00124/2020, UIDP/00124/2020 and Social Sciences DataLab - PINFRA/22209/2016), POR Lisboa and POR Norte (Social Sciences DataLab, PINFRA/22209/2016). All errors are our own. Publisher Copyright: © 2023 The Author(s)We study the firm-level responses to a substantial increase in transportation costs in the wake of a quasi-experiment that introduced tolls in a subset of Portuguese highways. Exploiting a unique dataset encompassing the universe of Portuguese private firms, we find that the introduction of tolls caused a substantial decrease in turnover (−10.2%) and productivity (−4.3%) in treated firms vis-Ă -vis firms in the comparison group. In response to the tolls, firms substantially cut employment-related expenses and purchases of other inputs. Labor costs were reduced by both employment cuts and a decrease in average wages. While firms did not increase inventory, there is some evidence for increased firm exit, in particular by firms in tradables sectors.publishersversionpublishe

    Evaluation of four clinical metrology instruments for the assessment of osteoarthritis in dogs

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    Research Areas: Agriculture; Veterinary Sciences; ZoologyOsteoarthritis (OA) is the most commonly diagnosed joint disease in companion animals, and proper tools are necessary to assess patients and response to treatment. We aimed to perform the psychometric evaluation of several clinical metrology instruments (CMI), developed to evaluate pain and assess outcome. Fifty police working dogs with bilateral hip OA were assessed in a prospective, randomised, double-blinded study. Patients were evaluated using a stance analyser in six different moments divided over a 180-day period. Pedometer step count, weight-bearing symmetry index and deviation from normal weight-bearing were calculated and used for criterion validity. In each evaluation moment, a copy of the Hudson Visual Analogue Scale (HVAS), Canine Brief Pain Inventory (CBPI), Liverpool Osteoarthritis in Dogs (LOAD) and Canine Orthopaedic Index (COI) were completed by the dogs’ handlers. Correlations between CMIs were evaluated as construct validity. Further evaluation was performed with the Kaiser–Meyer–Olin measure of sampling adequacy, Eigenvalue and scree-plot analysis. Internal consistency was tested with Cronbach’s α. Significant weak correlation was found between all CMIs and stance analysis symmetry index measure and deviation, indicating criterion validity. Significant weak correlation was also found between pedometer count and LOAD plus COI. Cronbach’s α was 0.80 for HVAS, 0.98 for CBPI, 0.97 for LOAD and 0.98 for COI. Significant strong correlation was observed between CMIs, indicating construct validity. We present criterion and construct validity of these CMIs, which are able to capture various dimensions of OA. They can be used for the evaluation of osteoarthritis and response to treatment in dogs.info:eu-repo/semantics/publishedVersio
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