28 research outputs found

    Total phenolic content, antioxidant and antibacterial activities of the extract of ephedra procera fisch. et mey

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    Ephedra procera belonging to the family Ephedraceae is a poison and medicinal plant. The main aim of the present study was to determine total phenolic content and antioxidant and antibacterial activities of ethanolic extract from the aerial parts of E. procera collected from a natural habitat in Chaharmahal va Bakhtiari province, Southwestern Iran. The total phenolic content of the extract by Folin-Ciocalteu method and the antioxidant activity using DPPH assay were determined. The antibacterial activity, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) of the extract were evaluated against five bacteria, including Proteus vulgaris, Pseudomonas aeruginosa, Enterobacter aerogenes, Bacillus cereus and Staphylococcus aureus. Total phenolic content in the extract of E. procera was 0.718 mg tannic acid/g dry weight extract. The results indicated that the ethanolic extract of E. procera exhibited radical scavenging activity. In addition, the results of this study confirmed that the ethanolic extract of E. procera exhibited antibacterial activity. In conclusion, the extract of E. procera could be an important source of phenolic components with antioxidant capacity and antibacterial activity.Naser Vahed Dehkordi, Mehrdad Ataie Kachouie, Abdollah Ghasemi Pirbalouti, Fatemeh Malekpoor and Mohammad Rabe

    A data science approach for quantifying spatio-temporal effects to graft failures in organ transplantation

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    This is the author accepted manuscript. The final version is available from IEEE via the DOI in tis recordThe transplantation of solid organs is one of the most important accomplishments of modern medicine. Yet, organ shortage is a major public health issue; 8,000 people died while waiting for an organ in 2014. Meanwhile, the allocation system currently implemented can lead to organs being discarded and the medical community still investigates factors that affects early graft failure such as distance and ischemic time. In this paper, we investigate early graft failure under a spatio-temporal perspective using a data science unified approach for all six organs that is based on complementary cumulative analysis of both distance and ischemic time. Interestingly, although distance seems to highly affect some organs (e.g. liver), it appears to have no effect on others (e.g. kidney). Similarly, the results on ischemic time confirm it affects early graft failure with higher influence for some organs such as (e.g. heart) and lower influence for others such as (e.g. kidney). This poses the question whether the allocation policies should be individually designed for each organ in order to account for their particularities as shown in this work

    Cell delivery systems using alginate : carrageenan hydrogel beads and fibers for regenerative medicine applications

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    The present work was focused on the development and characterization of new hydrogel systems based on natural origin polymers, namely, alginate and carrageenan, into different formats and with adequate properties to sustain the viability of encapsulated cells, envisioning their application as cell delivery vehicles for tissue regeneration. Different formulations of alginate and carrageenan hydrogels and different processing parameters were considered to determine the best conditions required to achieve the most adequate response in terms of the mechanical stability, cell viability, and functionality of the developed systems. The morphology, size, and structure of the hydrogels and their degradation behavior and mechanical properties were evaluated during this study. In addition to cytotoxicity studies, preliminary experiments were carried out to investigate the ability of alginate−carrageenan beads/fibers to encapsulate chondrocytes. The results obtained indicated that the different formulations, both in the form of beads and fibers, have considerable potential as cell-carrier materials for cell delivery in tissue engineering/ regenerative medicine applications.European NoE EXPERTISSUES - NMP3-CT-2004-500283Fundação para a Ciência e a Tecnologia (FCT) - SFRH/BD/64070/2009

    A systematic review of attitudes, anxiety, acceptance, and trust towards social robots

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    As social robots become more common, there is a need to understand how people perceive and interact with such technology. This systematic review seeks to estimate people’s attitudes toward, trust in, anxiety associated with, and acceptance of social robots; as well as factors that are associated with these beliefs. Ninety-seven studies were identified with a combined sample of over 13,000 participants and a standardized score was computed for each in order to represent the valence (positive, negative, or neutral) and magnitude (on a scale from 1 to − 1) of people’s beliefs about robots. Potential moderating factors such as the robots’ domain of application and design, the type of exposure to the robot, and the characteristics of potential users were also investigated. The findings suggest that people generally have positive attitudes towards social robots and are willing to interact with them. This finding may challenge some of the existing doubt surrounding the adoption of robotics in social domains of application but more research is needed to fully understand the factors that influence attitudes

    This content has been downloaded from IOPscience. Please scroll down to see the full text. An automated two-phase system for hydrogel microbead production An automated two-phase system for hydrogel microbead production

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    Abstract Polymeric beads have been used for protection and delivery of bioactive materials, such as drugs and cells, for different biomedical applications. Here, we present a generic two-phase system for the production of polymeric microbeads of gellan gum or alginate, based on a combination of in situ polymerization and phase separation. Polymer droplets, dispensed using a syringe pump, formed polymeric microbeads while passing through a hydrophobic phase. These were then crosslinked, and thus stabilized, in a hydrophilic phase as they crossed through the hydrophobic-hydrophilic interface. The system can be adapted to different applications by replacing the bioactive material and the hydrophobic and/or the hydrophilic phases. The size of the microbeads was dependent on the system parameters, such as needle size and solution flow rate. The size and morphology of the microbeads produced by the proposed system were uniform, when parameters were kept constant. This system was successfully used for generating polymeric microbeads with encapsulated fluorescent beads, cell suspensions and cell aggregates proving its ability for generating bioactive carriers that can potentially be used for drug delivery and cell therapy

    An automated two-phase system for hydrogel microbead production

    No full text
    Polymeric beads have been used for protection and delivery of bioactive materials, such as drugs and cells, for different biomedical applications. Here, we present a generic two-phase system for the production of polymeric microbeads of gellan gum or alginate, based on a combination of in situ polymerization and phase separation. Polymer droplets, dispensed using a syringe pump, formed polymeric microbeads while passing through a hydrophobic phase. These were then crosslinked, and thus stabilized, in a hydrophilic phase as they crossed through the hydrophobic–hydrophilic interface. The system can be adapted to different applications by replacing the bioactive material and the hydrophobic and/or the hydrophilic phases. The size of the microbeads was dependent on the system parameters, such as needle size and solution flow rate. The size and morphology of the microbeads produced by the proposed system were uniform, when parameters were kept constant. This system was successfully used for generating polymeric microbeads with encapsulated fluorescent beads, cell suspensions and cell aggregates proving its ability for generating bioactive carriers that can potentially be used for drug delivery and cell therapy.Fundação para a Ciência e a Tecnologia (FCT

    Domestic drones : context of use in research literature

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    Domestic robotic entities are on the rise, out of which, domestic drones are taking place in our society as one of the upcoming interactive technologies that we will see in our daily lives. In this paper, we scope for research literature that addresses the use of domestic drones within our environments to understand the current usage as well as identifying future research directions. After performing a search based collection of relevant papers in the ACM digital library (N=61 papers), we analysed the drone's application areas, their interaction modalities, the target users, and the level of autonomy of the proposed systems. The results show interesting trends in the modalities of interaction (visual projection combined with hand/foot gestures) as well as important research gaps such as child-drone interaction, and the use of drones for healthcare or education, given that currently most use cases for domestic drones are generic in nature
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