361 research outputs found

    Socially assistive robotics: robot exercise trainer for older adults

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    Physical activities have tremendous benefit to older adults. A report from the World Health Organization has mentioned that lack of physical activity contributed to around 3.2 million premature deaths annually worldwide. Research also shows that regular exercise helps the older adults by improving their physical fitness, immune system, sleep and stress levels, not to mention the countless health problems it reduces such as diabetes, cardiovascular disease, dementia, obesity, joint pains, etc. The research reported in this paper is introducing a Socially Assistive Robot (SAR) that will engage, coach, assess and motivate the older adults in physical exercises that are recommended by the National Health Services (NHS) in the UK. With the rise in the population of older adults, which is expected to triple by 2050, this SAR will aim to improve the quality of life for a significant proportion of the population. To assess the proposed robot exercise trainer, user’s observational evaluation with 17 participants is conducted. Participants are generally happy with the proposed platform as a mean of encouraging them to do regular exercise correctly

    Turbulent characteristics of a semiarid atmospheric surface layer from cup anemometers – effects of soil tillage treatment (Northern Spain)

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    International audienceThis paper deals with the characteristics of turbulent flow over two agricultural plots with various tillage treatments in a fallow, semiarid area (Central Aragon, Spain). The main dynamic characteristics of the Atmospheric Surface Layer (ASL) measured over the experimental site (friction velocity, roughness length, etc.), and energy budget, have been presented previously (Frangi and Richard, 2000). The current study is based on experimental measurements performed with cup anemometers located in the vicinity of the ground at 5 different levels (from 0.25 to 4 m) and sampled at 1 Hz. It reveals that the horizontal wind variance, the Eulerian integral scales, the frequency range of turbulence and the turbulent kinetic energy dissipation rate are affected by the surface roughness. In the vicinity of the ground surface, the horizontal wind variance logarithmically increases with height, directly in relation to the friction velocity and the roughness length scale. It was found that the time integral scale (and subsequently the length integral scale) increased with the surface roughness and decreased with the anemometer height. These variations imply some shifts in the meteorological spectral gap and some variations of the spectral peak length scale. The turbulent energy dissipation rate, affected by the soil roughness, shows a z-less stratification behaviour under stable conditions. In addition to the characterization of the studied ASL, this paper intends to show which turbulence characteristics, and under what conditions, are accessible through the cup anemometer

    Performance comparison of baseline routing protocols in pocket switched network

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    Pocket Switched Network (PSN) is a branch of Delay Tolerant Network (DTN) which is intended to work in a challenged network. Challenged network is network with lack of infrastructure such as disaster area. As such, the network has intermittent connectivity. PSN provides a new paradigm to distribute messages in the network by taking advantage of roaming nodes from one place to another. In this paper, network performances of eight PSN routing protocols are investigated namely, First Contact, Direct Delivery, Epidemic, PRotocol using History of Encounter and Transitivity (PRoPHET), Spray and Wait, Binary Spray and Wait, Fuzzy Spray, Adaptive Fuzzy Spray and Wait. The performance metrics are packet delivery ratio, overhead ratio and average latency. Opportunistic Network Environment (ONE) simulator is used to evaluate the network performance. Experiments show that Epidemic has the best performance in term of message delivery ratio, but it has the highest overhead ratio. Direct Delivery has the lowest overhead ratio (zero overhead ratio) and PRoPHET has the lowest latency average

    Preparation and characterization of artemether inclusion complexes with hydroxypropyl-β-cyclodextrin

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    Purpose: To investigate experimentally the inclusion of artemether into the cavity of  hydroxypropyl-β-cyclodextrin and examine its effect on the solubility and dissolution rate of the drug.Methods: Inclusion complexes of artemether with hydroxypropyl-β-cyclodextrin of molar ratios 1:1, 1:2 and 1:3 were prepared using the kneading method. Phase solubility analysis and in vitro dissolution studies were utilized in evaluating the influence of inclusion complex formation on the solubility and dissolution rate of the drug. The complexes were characterized using differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR). The inclusion complex containing equimolar concentrations of artemether and hydroxypropyl-β-cyclodextrin was then formulated into tablets via direct compression and  evaluated for various pharmaceutical characteristics including hardness, friability, absolute drug content and comparative in vitro dissolution profiles with some  commercially available brands of artemether.Results: The phase solubility diagram for the formed complexes in water at 37 oC indicated a linear curve soluble complex system (referred to as the AL system), and a stability constant (KC) value of 143 M-1. Evidence consistent with inclusion complex formation was obtained using FT-IR and DSC. The formulated inclusion complex tablets exhibited a higher rate of dissolution than the pure drug and commercial brands, showing 3.9-, 1.8- and 1.6-fold increases, respectively, over a period of 15 min.Conclusion: Inclusion complexation of artemether with hydroxypropyl-β-cyclodextrin is a promising approach to enhance the solubility and dissolution rate of the drug.Keywords: Artemether, 2-Hydroxypropyl-β-cyclodextrin, Dissolution, Solubility enhancement, Inclusion comple

    Interfacial friction in upward annular gas–liquid two-phase flow in pipes

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    Accurate prediction of interfacial friction between the gas and liquid in annular two-phase flow in pipes is essential for the proper modelling of pressure drop and heat transfer coefficient in pipeline systems. Many empirical relationships have been obtained over the last half century. However, they are restricted to limited superficial liquid and gas velocity ranges, essentially apply to atmospheric pressures, and the relationships are only relevant for pipes with inner diameters between 10 and 50 mm. In this study, we carried out experiments in a large diameter flow loop of 101.6 mm internal diameter with the superficial gas and liquid ranges of 11–29 m/s and 0.1–1.0 m/s respectively. An examination of published interfacial friction factor correlations was carried out using a diverse database which was collected from the open literature for vertical annular flow. The database includes measurements in pipes of 16–127 mm inner diameter for the liquid film thickness, interfacial shear stress, and pressure gradient for air-water, air-water/glycerol, and argon-water flows. Eleven studies are represented with experimental pressures of up to 6 bar. Significant discrepancies were found between many of the published correlations and the large pipe data, primarily in the thick film region at low interfacial shear stress. A correlation for the interfacial friction factor was hence derived using the extensive database. The correlation includes dimensionless numbers for the effect of the diameter across pipe scales to be better represented and better fit the wide range of experimental conditions, fluid properties, and operating pressures

    Маніпулятивні та комунікативні елементи суспільно-політичної діяльності мас-медіа

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    No Phlebotomine sandflies had ever been reported in the Comoros Archipelago, including the three islands of the Republic of the Union of Comoros (Grande Comore, Moheli and Anjouan) and the French oversea department of Mayotte. During three field surveys carried out in 2003, 2007 and 2011, we provided the first record of Phlebotomine sandflies in this area. A total of 85 specimens belonging to three species were caught: a new species S. (Vattieromyia) pessoni n. sp. (two females from Grande Comore), a new subspecies of Sergentomyia (Rondanomyia) goodmani (80 specimens from Grande Comore and one from Anjouan) and Grassomyia sp. (two females from Moheli). The individualisation of chese taxa was inferred both from morphological criteria and sequencing of a part of the cytochrome b of the mitochondrial DNA. These taxa are closely related to Malagasy sandflies

    Environmental Susceptibility and Resistance to Coronavirus Disease-19 (COVID-19): A Review

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    It is believed that certain environmental factors modulate coronavirus disease-19 (COVID-19). This review outlines the role of environmental factors in COVID-19 infectivity, spread, and severity. Relevant articles were retrieved from Google Scholar, SpringerLink, and Scopus, then pooled and duplicates removed with EndNote software. Available information reveals that temperature, relative humidity (RH), sunlight, pollutants, and population density modulate COVID-19 infectivity and pathogenicity. COVID-19 spread is promoted by low temperature (< 25 °C) and RH (< 40%), whereas it is inhibited by high temperature (> 25 °C) and RH (> 40%). Sunlight exposure alters the virus’s genetic material and boosts the host’s immune function by raising serum vitamin D (25-hydroxyvitanim D), reducing the virus’s viability and replication. Prolonged indoor stays with poor ventilation cause re-breathing of the air and increase carbon dioxide concentration, particularly in crowded rooms, predisposing to COVID-19. Pollutants, including particulate matter, nitrogen dioxide, ozone, and sulphur dioxide, may overexpress the virus’s receptor called angiotensin-converting enzyme 2 (ACE2), thereby increasing the virus’s infectivity. Pollutants may also induce inflammation of the respiratory tract, weakening the immune function and thereby increasing susceptibility to COVID-19. High population density increases body contact and thus susceptibility to the virus. To stem the incidence and mortality of COVID-19, the mentioned environmental factors must be kept at healthy levels

    Toward N-nitrosamines free water: Formation, prevention, and removal

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    This study elucidates the recent trends in the formation, prevention, and removal of N-nitrosamines such as Nnitrosodimethylamine(NDMA) from wastewater or drinking water. Reports are rife on the occurrence of NDMA in areas such as amine degradation during postcombustion CO2 capture (PCC), chlorinated/chloraminated and ozonated drinking water, smoked or cooked foods personal care, tobacco and pharmaceutical products. The major routes responsible for the formation of NDMA in portable waters include chlorination/ chloramination and ozonation. The major NDMA precursors are secondary, tertiary, and quaternary amines such as dimethylamine, diethanolamine, and triethanolamine. Due to the environmental and public health concerns posed by this contaminant, a proactive approach is necessary towards suppressing their occurrence, as well as their removal. Consequently, this study critically reviewed the formation, prevention, and removal of N-nitrosamines. The study discussed NDMA prevention techniques, such as physical adsorption, preoxidation, and biological activated carbon. The removal techniques discussed here include physicochemical (such as combined adsorption and microwave irradiation and UV photolysis), bioremediation, catalytic reduction, and dope technology. Irrespective of the effectiveness and seemingly economic viability of some of these technologies, preventing the occurrence of NDMA right from the outset is more potent because the treatments consume more energy

    Cartilage regeneration by chondrogenic induced adult stem cells in osteoarthritic sheep model

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    Objectives: In this study, Adipose stem cells (ADSC) and bone marrow stem cells (BMSC), multipotent adult cells with the potentials for cartilage regenerations were induced to chondrogenic lineage and used for cartilage regenerations in surgically induced osteoarthritis in sheep model. Methods: Osteoarthritis was induced at the right knee of sheep by complete resection of the anterior cruciate ligament and medial meniscus following a 3-weeks exercise regimen. Stem cells from experimental sheep were culture expanded and induced to chondrogenic lineage. Test sheep received a single dose of 2×107 autologous PKH26-labelled, chondrogenically induced ADSCs or BMSCs as 5 mls injection, while controls received 5 mls culture medium. Results: The proliferation rate of ADSCs 34.4±1.6 hr was significantly higher than that of the BMSCs 48.8±5.3 hr (P = 0.008). Chondrogenic induced BMSCs had significantly higher expressions of chondrogenic specific genes (Collagen II, SOX9 and Aggrecan) compared to chondrogenic ADSCs (P = 0.031, 0.010 and 0.013). Grossly, the treated knee joints showed regenerated de novo cartilages within 6 weeks post-treatment. On the International Cartilage Repair Society grade scores, chondrogenically induced ADSCs and BMSCs groups had significantly lower scores than controls (P = 0.0001 and 0.0001). Fluorescence of the tracking dye (PKH26) in the injected cells showed that they had populated the damaged area of cartilage. Histological staining revealed loosely packed matrixes of de novo cartilages and immunostaining demonstrated the presence of cartilage specific proteins, Collagen II and SOX9. Conclusion: Autologous chondrogenically induced ADSCs and BMSCs could be promising cell sources for cartilage regeneration in osteoarthritis

    Economic Evaluation of Soy-Chocolate Beverage Drink

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    Abstract Soy-chocolate beverage drink is a nutritional health drink was obtained from soya bean and cocoa powder. The study was conducted to evaluate the economic analyses of soy-chocolate beverage drink production with a view to establishing the profitability of the investment. The method used in this study involved an investment decision model comprising Net present value (NPV), Benefit Cost Ratio (BCR) and Internal Rate of Return (IRR). The results indicates an NPV of N480, 535 discounted at 21%, BCR of 2.5 and IRR of 21.33% These positive values are indices to the fact that investment of soya chocolate beverage is a profitable venture and worthwhile
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