1,123 research outputs found
Clinical microbiology study of diabetic foot ulcer in Iran; pathogens and antibacterial susceptibility
The aim of this study was to investigate microbial pathogens and their antibiotic susceptibility profile in infected diabetic foot ulcers in Iranian patients. This was a one-year cross sectional study on diabetic patients with infected diabetic foot ulcer at Shariati Teaching Hospital, Tehran, Iran. Grade of ulcer was determined by Wagner's criteria. Specimens were obtained from the base of ulcer, deep part of the wound or aspiration and were tested with gram staining and antibacterial susceptibility was determined with both disk diffusion and E-Test methods. Total of 546 pathogens were isolated from 165 ulcers of 149 patients. Gram positive aerobes including Enterococcal species and methicillin resistant Staphylococcus aureus (S. aureus) (21.4 and 19.4%, respectively) were identified as the most common pathogens followed by Gram negative isolates including Escherichia coli and Pseudomonas-aeruginosa (12.6 and 5.4%, respectively). The majority of wounds were classified as Wagner grades 2 and 3 (15.7 and 75.7%). Appropriate empiric treatment to cover both these Gram positive and Gram negative pathogens is crucially important
Study of the antibacterial activity of total extract and Petroleum ether, chloroform, ethyl acetate and aqueous fractions of aerial parts of heliotropium bacciferum against staphylococcus aureus, Bacillus cereus, Pseudomonas aeruginosa, E.coli, Salmonella enteritidis
Heliotropium bacciferum is One of the plants belonging to the family Boraginaceae , which is Restricted distribution in the south of Iran. It is used for Hypotension, fever, stomach ulcers in traditional medicine. In this study, the antibacterial effects of extracts and fractions of chloroform, ethyl acetate and aqueous, aerial parts of Heliotropium bacciferum Forssk was evaluated against five bacterial strains. The methanol extract were prepared using the percolation method. Fractions of chloroform, Petroleum ether, ethyl acetate, methanol and aqueous respectively by Liquid - Liquid fractionation of the total extract were prepared. The antibacterial activity against two Gram positive bacteria, three Gram negative bacterial using Minimum inhibitory concentration in microplate and well plate method. Results showed that H. bacciferum extracts exhibited a significant activity against strains Staphylococcus aureus, Bacillus cereus,Pseudomonas aeruginosa, E.coli, Salmonella enteritidis. MIC and well plate is between 7.6-125 ÎĽg/ml. The results of this study indicate that extracts of the plant H.bacciferum has a antimicrobial effect against strains are listed And among the extracts, aqueous part is that most antibacterial effect of the other fraction and then methanolic extract has the greatest effect
Sleep Disturbances in Patients with Rheumatoid Arthritis
BACKGROUND: Sleep problems are frequent in chronic diseases like rheumatoid arthritis (RA). The present study was conducted to determine frequency of sleep disturbances and their relations with disease severity.METHODS: The present case-control study was performed on 100 rheumatoid patients who were referred to the rheumatology clinic at the Avicenna hospital. A hundred age- and sex- matched healthy individuals were recruited in the study as a control group. Pittsburgh Sleep Quality questionnaire, Insomnia Severity Index questionnaire and EpworthSleepiness Scale were used. The disease activity was calculated with the disease activity score 28. The collected data were analyzed using SPSS version 19.RESULTS: Mean scores of the sleep quality were 6.2±4.3 in patients and 4.6±2.5 in control group. 28% of the patients had good sleep quality whereas 72% had poor sleep quality. Daytime sleepiness was present in24.8% of the patients and 15% of the control group. Multiple logistic regressions showed that insomnia, pain and disease intensity were the most important factors that determine patients' sleep quality.CONCLUSION: The present study showed that sleep disturbances are frequent in patients with RA and may contribute to disease severity. It is recommended that rheumatoid patients be evaluated for sleep disturbances during routine examinations.KEY WORDS: Rheumatoid arthritis, Sleep quality, Insomnia, Daytime sleepines
Power Flow Control in Multi-Terminal HVDC Grids Using a Serial-Parallel DC Power Flow Controller
© 2013 IEEE. Multi-terminal HVDC (MT-HVDC) grids have no capability of power flow control in a self-sufficient manner. To address this important issue, utilization of dc-dc high power and high-voltage converters is motivated. However, proposing suitable partial-rated dc-dc converters as well as their suitable modeling and control in both primary and secondary control layers as well as the stability analysis are the existing challenges that should be alleviated beforehand. This paper addresses the control of power flow problem through the application of a power converter with a different connection configuration, namely, serial parallel dc power flow controller (SPDC-PFC). The SPDC-PFC input is the transmission line voltage, and its output is transmission line current. Therefore, employing a full-power dc-dc converter is avoided as a merit. Additionally, in this paper, the common two-layer MT-HVDC grid control framework comprised of primary and secondary layers is efficiently modified in order to integrate the SPDC-PFC. A differential direct voltage versus active power droop control scheme is applied to the SPDC-PFC at the local control layer, guaranteeing dynamic stability, while an extended dc power-flow routine - integrating the SPDC-PFC - is developed at the secondary control layer to ensure the static stability of the entire MT-HVDC grid. The proposed control framework enables the SPDC-PFC to regulate the flow of current/power in the envisioned HVDC transmission line. From the static and dynamic simulation results conducted on the test CIGRE B4 MT-HVDC grid, successful operation of the proposed SPDC-PFC and control solutions are demonstrated by considering power flow control action. In more detail, the SPDC-PFC successfully regulates the compensated lines' power to the desired reference both in static and dynamic simulations by introducing suitable compensation voltages. In addition, good dynamic performance under both SPDC-PFC power reference and wind power-infeed change is observed
Structure and Growth of Core–shell Nanoprecipitates in Al–Er–Sc–Zr–V–Si High-temperature Alloys
Lightweight Sc-containing aluminum alloys exhibit superior mechanical performance at high temperatures due to core–shell, L12-ordered trialuminide nanoprecipitates. In this study, the structure of these nanoprecipitates was studied, using different transmission electron microscopy (TEM) techniques, for an Al–Er– Sc–Zr–V–Si alloy that was subjected to a two-stage overaging heat treatment. Energy-dispersive X-ray spectroscopy of the spherical Al3(Sc, Zr, Er ,V) nanoprecipitates revealed a core–shell structure with an Sc- and Er-enriched core and a Zr-enriched shell, without a clear V outer shell. This structure is stable up to 72% of the absolute melting temperature of Al for extended periods of time. High-angle annular dark-field scanning TEM was used to image the {100} planes of the nanoprecipitates, demonstrating a homogeneous L12-ordered superlattice structure for the entire nanoprecipitates, despite the variations in the concentrations of solute atoms within the unit cells. A possible growth path and compositional trajectory for these nanoprecipitates was proposed using high-resolution TEM observations, where different rod-like structural defects were detected, which are considered to be precursors to the spherical L12-ordered nanoprecipitates. It is also hypothesized that the structural defects could consist of segregated Si; however, this was not possible to verify with HAADF-STEM because of the small differences in Al and Si atomic numbers. The results herein allow a better understanding of how the Al–Sc alloys’ core–shell nanoprecipitates form and evolve temporally, thereby providing a better physical picture for future atomistic structural mappings and simulations
Nutritional care of elderly patients in acute care settings: A qualitative study
© 2016 Japan Geriatrics Society. Aim: Poor nutritional status is common in older adult patients. The present study aimed to explore barriers and facilitators to nutritional care of elderly patients in acute care settings. Methods: Data were collected through individual face-to-face interviews with 12 registered nurses, and analyzed using interpretive description methodology. Results: Two core themes emerged from the analysis of data: (i) neglected care, with three subthemes of "support but also independence," "unsupportive environment" and "responsibility of the family;" and (ii) a humanitarian ethic, with two subthemes of "respect and dignity" and "humanitarian care." Conclusions: As an integral part of holistic care, elderly patient nutrition should be emphasised in health professional education, and promoted through managerial support, multidisciplinary collaborations, and implementation of appropriate monitoring and evaluation systems
Combination of theoretical and in situ experimental investigations of the role of lithium dopant in manganese nitride: a two-stage reagent for ammonia synthesis
Manganese nitride related materials are of interest as two-stage reagents for ammonia synthesis via nitrogen chemical looping. However, unless they are doped with a co-cation, manganese nitrides are thermochemically stable and a high temperature is required to produce ammonia under reducing conditions, thereby hindering their use as nitrogen transfer materials. Nevertheless, when lithium is used as dopant, ammonia generation can be observed at a reaction temperature as low as 300 °C. In order to develop strategies for the improvement of the reactivity of nitride materials in the context of two-stage reagents, it is necessary to understand the intrinsic role of the dopant in the mechanism of ammonia synthesis. To this end, we have investigated the role of lithium in increasing the manganese nitride reactivity by in situ neutron diffraction studies and N2 and H2 isotopic exchange reactions supplemented by DFT calculations
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