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Alternative sources of anticoagulants have arisen as a result of the increasing demand for safer anticoagulant clinical therapy, and the sulfated polysaccharides of seaweeds have gained attention in biomedicine. In this study, crude sulfated polysaccharide fractions (denominated Hf1, Hf2 and Hf3) were obtained from the red marine algaHalymenia floresia and the anticoagulant properties of a soluble crude polysaccharide fraction (Hf2s) were assayed. The three differential extractions yielded 38.6%. The polysaccharides are composed mainly of galactose, with small amounts of xylose and glucose. The anticoagulant properties of Hf2s containing 53.8% sulfate and 3% protein was also compared to those of heparin (193.0 IU mg-1) by assays of activated partial thromboplastin time (APTT) and thrombin time (TT) using normal human plasma. Hf2s showed a higheranticoagulant activity (68.4 IU mg-1) than those of Hf1s and Hf3s, whose activities were 37.6 and 36.6 IU mg-1, respectively. The compound was less active than heparin, but its anticoagulant mechanism suggested that it is dependent on cofactor heparin II to inhibit thrombin activity, but not on cofactors VIII and IX. Therefore, the polysaccharide from H. floresia interfered on coagulation cascade.O aumento da demanda por anticoagulantes para a terapia clínica tem motivado a busca por fontes alternativas de anticoagulantes mais seguros e os polissacarídeos sulfatados de algas marinhas têm ganhado atenção na biomedicina. Objetivou-se obter frações de polissacarídeossulfatados brutos (denominadas Hf1; Hf2 e Hf3) da alga marinha vermelha Halymenia floresia e para avaliar as propriedades anticoagulantes de uma fração polissacarídica bruta solúvel anticoagulante (Hf2s). As três extrações diferenciais renderam 38,60%. Os polissacarídeos são principalmente compostos de galactose com pequenas quantidades de xilose e glucose. As propriedades anticoagulantes da Hf2s, contendo 53,80% de sulfato e 3% de proteínas, foram também comparadas com a heparina (193,00 UI mg-1) pelo ensaio do tempo de tromboplastina parcial ativada (TTPA) e tempo de trombina (TT), usando plasma humano normal. A Hf2s apresentou maior atividade anticoagulante (68,40 UI mg-1) que Hf1s a Hf3s, cujas atividades foram 37,60 e 36,60 UI mg-1, respectivamente. O composto foi menos ativo que a heparina, mas sugere-se que o mecanismo anticoagulante seja dependente do cofator II da heparina para inibição da atividade da trombina, exceto pelos cofatores VIII a IX. Portanto, o polissacarídeo de H. floresia interferiu na cascata de coagulação.

Heparin (HEP) is known due to their side effects and the red seaweed Halymenia floresia (Hf) sulfated polysaccharides (SP) are heparinoids. In this study we purified the Hf-SP obtained from an aqueous extract and evaluated their anticoagulant activities. Hf-SP1 (25°C), Hf-SP2 (80°C) and Hf-SP3 (80°C) were sequentially isolated. Hf-SP3 had the highest sulfate content (37.45%). Hf-SP3 was fractionated by ion exchange chromatography on a DEAE-cellulose column using a NaCl gradient. Fractions were lyophilized and submitted to 0.5% agarose gel electrophoresis. The anticoagulant activity was evaluated by the activated partial thromboplastin time using rabbits plasma and expressed in international units per mg of SP using standard HEP (193 IU mg-1). The chromatographic procedure separated into four different SP fractions (F I, F II, F III and F IV) eluted at concentrations of 0.50, 0.75, 1.00 and 1.25 M of NaCl, respectively, reveling among them different marked on charge density, when compared by electrophoresis. F III had the highest anticoagulant activity (10.72 IU mg-1), suggesting that the sulfate is important in this process. In conclusion, our results suggest that sequential extractions of Hf-SP are an important biotechnological tool for identification of novel anticoagulants and studies of structural characterization are already in progress.

Alternative sources of anticoagulants have arisen as a result of the increasing demand for safer anticoagulant clinical therapy, and the sulfated polysaccharides of seaweeds have gained attention in biomedicine. In this study, crude sulfated polysaccharide fractions (denominated Hf1, Hf2 and Hf3) were obtained from the red marine alga Halymenia floresia and the anticoagulant properties of a soluble crude polysaccharide fraction (Hf2s) were assayed. The three differential extractions yielded 38.6%. The polysaccharides are composed mainly of galactose, with small amounts of xylose and glucose. The anticoagulant properties of Hf2s containing 53.8% sulfate and 3% protein was also compared to those of heparin (193.0 IU mg-1) by assays of activated partial thromboplastin time (APTT) and thrombin time (TT) using normal human plasma. Hf2s showed a higher anticoagulant activity (68.4 IU mg-1) than those of Hf1s and Hf3s, whose activities were 37.6 and 36.6 IU mg-1, respectively. The compound was less active than heparin, but its anticoagulant mechanism suggested that it is dependent on cofactor heparin II to inhibit thrombin activity, but not on cofactors VIII and IX. Therefore, the polysaccharide from H. floresia interfered on coagulation cascade.

Gliding has evolved independently as an isolated adaptive event within many vertebrate taxa. Yet, the underlying selection forces that led to these innovative adaptations remain ambiguous, especially in species that preclude direct observation. Our study utilized accelerometry and machine learning algorithms to compare the behavioural repertoires of two sympatric species, the Mahogany glider (Petaurus gracilis) and brushtail possum (Trichosaurus vulpecula), as to explore previously proposed selection pressures such as energy expenditure (VeBA), canopy use and ground avoidance measured by activity budgets. We found that mahogany gliders on average expend more activity‐related energy than brushtail possums but at different stages throughout the day. Canopy use was observed to be greater amongst mahogany gliders than brushtail possums, and we observed frequent ground use in brushtail possums yet none in mahogany gliders. The study found strong evidence to support ground avoidance as a potential driver for gliding evolution. The implications of these findings are important when considering the lack of knowledge surrounding evolved gliding behaviours in marsupials. Furthermore, the use of accelerometers and machine learning algorithms in behavioural studies has proven to be a robust and informative method and should be incorporated into future studies to understand the evolution of gliding behaviour. [ABSTRACT FROM AUTHOR]

Anna Bowers,1,2 Kristin Cleverley,1,2 Claudia Di Clemente,1 Joanna Henderson1 1Centre for Addiction and Mental Health, 2University of Toronto, Toronto, ON, Canada Abstract: There is an evident disparity between the number of youth who report experiencing problematic substance use and the number who seek treatment. To address this disparity, it is important to understand the reasons youth do and do not seek substance use treatment. Using qualitative data obtained from semistructured interviews with 31 youth aged 17–25 years presenting for treatment at a mental health hospital, the current study identifies themes in the factors that youth identify as having influenced them to seek or delay treatment. In alignment with self-determination theory, youth identified internal factors, such as wanting to better their academic, social, or financial situation, and external factors, such as familial pressure, as motivating them to seek treatment. Factors beyond those encompassed by self-determination theory were also revealed as having influenced youth decisions to seek treatment for substance abuse. These predominantly included structural factors, including satisfaction with previous treatment, accessibility of services, and availability of clinicians. These findings provide important insight for first-contact professionals and service providers looking to enhance youth motivation to seek and engage in treatment. Limitations and opportunities for future research are discussed. Keywords: substance use, mental health, youth, treatment seeking, motivation

In 2015, Transport Network Companies (TNC) such as Grab and Uber were introduced in the Philippines. With the worsening traffic management system in the country, TNC units use the power of an application to cater the commuting needs and demands of the Filipino commuting public following a car-sharing principle. Taking into account their startup success, the conventional taxi industry has been struggling. On this basis, this phenomenological study therefore involves an in-depth understanding of the struggles and subsequent condition of the taxi industry amid operations of TNCs. With the use of snowball and convenience sampling, the study involved semi-structured interviews with drivers of conventional taxi, commuters, and the Philippines' Land Transportation Franchising and Regulatory Board (LTFRB) members to obtain perspectives from the regulating body. Employing Billups’(2016) qualitative data analysis method, six themes emerged including Effects of Transport Network Companies, Protests and Complaints of Taxi Drivers, Consequent Actions of Taxi Drivers due to Income Reduction, Motivations for Taxi Driving Business Continuity, Perceptions of Taxi Drivers on TNVS, and Commuter Perspective on both Transport Services. Based on the findings, it is concluded that since the TNCs introduction, the conventional taxi industry has been bombarded of varied issues relating to the quality of transport service they provide in terms of convenience, comfort and ease, affordability, and accessibility. These findings then translate to the need of a partial deregulation that involves amendments on some memorandum circulars, and the pioneered Code of Ethics for the entire Philippine Taxi Industry so as to sustain and correspondingly compete with TNCs in relation to the demands of the market.

Copyright of Acta Scientiarum: Biological Sciences is the property of Universidade Estadual de Maringa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The lifetime of implants is affected by the aggressivity of the physiological medium, which mainly results from the relatively high concentration of ion chlorides. There are, however, other transient situations that may enhance the aggressivity of the environment in the adjacent zones to the implant. For example, during the first days of the implantation is rather frequent to get bruises, inflammation, and even infections. These modifications could dramatically influence the corrosion behaviour and decrease the life expectancy of the implant. In this work the corrosion behaviour of the MA 956, which has been proposed as a new biomaterial, is investigated under experimental conditions of low pH and deareation, which simulate the most typical medical complications in service.Además del contenido en iones cloruro que ya hacen del medio fisiológico un entorno corrosivo, en la vida de un implante se producen situaciones transitorias que pueden provocar cambios locales del medio en torno al implante. En los primeros días de la implantación de un biomaterial es relativamente frecuente que se produzcan hematomas, con bajada en el valor del pH, inflamación e incluso infección. Estas situaciones químicas cambiantes, aunque en general son transitorias pueden modificar drásticamente el comportamiento a corrosión de un biomaterial y por tanto afectar negativamente a la vida en servicio de las prótesis. En este trabajo se presenta el comportamiento a corrosión de la superaleación MA 956 con capa de alúmina, en suero fisiológico, en condiciones de bajo pH y desaireación para simular la posibilidad de hematomas, inflamación e infección de los tejidos que rodean la prótesis, dado que esta superaleación está propuesta como nuevo biomaterial.

Copyright of Acta Scientiarum: Technology is the property of Universidade Estadual de Maringa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Bipedalism has repeatedly evolved in many independent lineages throughout tetrapod history. Despite being widespread, the fundamental biomechanical factors involved in bipedalism remain unclear. This study experimentally investigated bipedalism in facultatively bipedal lizards and obligatorily bipedal birds to explore temporal asymmetry in the vertical component of the ground reaction force (Fz). Both lizards and birds showed significant temporal asymmetry – with higher vertical forces exerted earlier in the stance – as indicated by three different measures computed from force‐time profiles. This result parallels those reported previously for other bipedal animal groups that have a forward situated whole‐body centre of mass (COM), such as kangaroos and non‐human primates. Humans, in contrast, exhibit an orthograde posture with the COM close the hips, and show little temporal asymmetry in Fz, particularly during walking. Across a wide range of quadrupedal animals, temporal asymmetry is quite variable. Collectively, these results suggest that an ‘early‐skewed’ Fz may be an important feature of steady bipedal locomotion when the COM is forward of the hips, although an exact mechanism of cause‐and‐effect, if one exists, remains to be established. This finding has relevance for attempts at better understanding bipedal locomotion in extinct animals that likely had a COM located forward of the hips, such as carnivorous dinosaurs. [ABSTRACT FROM AUTHOR]

How extinct, non-avian theropod dinosaurs moved is a subject of considerable interest and controversy. A better understanding of non-avian theropod locomotion can be achieved by better understanding terrestrial locomotor biomechanics in their modern descendants, birds. Despite much research on the subject, avian terrestrial locomotion remains little explored in regards to how kinematic and kinetic factors vary together with speed and body size. Here, terrestrial locomotion was investigated in twelve species of ground-dwelling bird, spanning a 1,780-fold range in body mass, across almost their entire speed range. Particular attention was devoted to the ground reaction force (GRF), the force that the feet exert upon the ground. Comparable data for the only other extant obligate, striding biped, humans, were also collected and studied. In birds, all kinematic and kinetic parameters examined changed continuously with increasing speed, while in humans all but one of those same parameters changed abruptly at the walk-run transition. This result supports previous studies that show birds to have a highly continuous locomotor repertoire compared to humans, where discrete ‘walking’ and ‘running’ gaits are not easily distinguished based on kinematic patterns alone. The influences of speed and body size on kinematic and kinetic factors in birds are developed into a set of predictive relationships that may be applied to extinct, non-avian theropods. The resulting predictive model is able to explain 79–93% of the observed variation in kinematics and 69–83% of the observed variation in GRFs, and also performs well in extrapolation tests. However, this study also found that the location of the whole-body centre of mass may exert an important influence on the nature of the GRF, and hence some caution is warranted, in lieu of further investigation. [ABSTRACT FROM AUTHOR]

Primary blast injury (PBI) is the general term that refers to injuries resulting from the mere interaction of a blast wave with the body. Although few instances of primary ocular blast injury, without a concomitant secondary blast injury from debris, are documented, some experimental studies demonstrate its occurrence. In order to investigate PBI to the eye, a finite element model of the human eye using simple constitutive models was developed. The material parameters were calibrated by a multi-objective optimisation performed on available eye impact test data. The behaviour of the human eye and the dynamics of mechanisms occurring under PBI loading conditions were modelled. For the generation of the blast waves, different combinations of explosive (trinitrotoluene) mass charge and distance from the eye were analysed. An interpretation of the resulting pressure, based on the propagation and reflection of the waves inside the eye bulb and orbit, is proposed. The peculiar geometry of the bony orbit (similar to a frustum cone) can induce a resonance cavity effect and generate a pressure standing wave potentially hurtful for eye tissues. [ABSTRACT FROM PUBLISHER]