348 research outputs found

    Effect of manganese oxide nanoparticle on growth performance and blood cells of rainbow trout (Oncorhynchus mykiss Walbaum 1792) fingerlings

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    This study was aimed to use nano manganese oxide (Mn2O3) as a mineral premix on growth parameters followed by the erythrocyte and leukocyte properties of rainbow trout (Oncorhynchus mykiss) fingerlings. 450 specimens of rainbow trout fingerlings with an average weight of 9.1±0.3 g after acclimation to the experimental condition were randomly distributed in triplicate to five treatments of raceways ponds with open flow. Basal diet as control treatment was prepared by adding no supplemental manganese mineral. Other experimental diets were prepared by adding 4, 8, 12 mg and 12 mg nano manganese oxide followed by 12 mg manganese sulfate (as positive control treatment) to each kg diet. The Fish were fed for 8 weeks under experimental conditions with the corresponding diets. At the end of feeding trial, growth performance followed by the hematological parameters were determined by cutting the caudal peduncle (n=5). Results demonstrated no significant differences in final weigh, specific growth rate, protein efficiency ratio, and condition factor of the fish among the treatments. However, erythrocytes, hemoglobin, and hematocrit of fish fed by 12 mg kg-1 nanoparticle manganese oxide were significantly higher than fish in other treatments (p<0.05), while no significant difference was found in erythrocyte indices including mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) between the treatments. There is also no significant difference in former variables of the fish fed manganese sulfate and control diet. Findings of the present study showed that the use of nano manganese oxide increase some blood parameters of rainbow trout fingerlings including number of erythrocytes, hemoglobin, and hematocrit

    Membrane Separation for Gases: Materials, Preparation Methods and Transport Mechanism

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    Gas adsorption and permeation of CO2 gas weremeasured on two carbon molecular sieve membranes over awide pressure range. The two membrane samples werefabricated under similar conditions but with different degreesof carbonization. The pressure dependence of the permeationtime lag was investigated and it is found that the diffusioncoefficient takes a stronger functional dependence on loadingthan the Darken relation and this dependence increases withthe degree of carbonization

    Versatile Like a Seahorse Tail: A Bio-Inspired Programmable Continuum Robot For Conformal Grasping

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    Compliant grasping is an important function of continuum robots that interact with humans and/or unpredictable environments. However, the existing robots often have cross-sections that remain constant along their length. This causes the robots to exhibit poor grasping ability, especially when dealing with objects with diverse curvatures. Here, inspired by the high adaptability of seahorse tails in grasping, we proposed a cable-driven continuum robot with tapered tensegrity, capable of conformally grasping objects with various curvatures. To characterize the effects of the tapering on the robot’s kinematics, we derived a mechanical model using multi-body dynamic framework for both predicting the configuration and developing a control strategy for cables. Theoretical predictions indicate that the curvature of each unit can be regulated by altering the length of the cables, allowing the robot to conform to objects with curvatures ranging from 1.48 m-1 to 28.21 m-1. We further employed a continuum robot and tested the control strategy that can be used for grasping floating objects when the curvature of the objects is used as the input. Our robotic design, which presents an example of embedded physical intelligence, can inspire in situ characterization techniques for collecting marine debris

    Is correction for metallic artefacts mandatory in cardiac SPECT/CT imaging in the presence of pacemaker and implantable cardioverter defibrillator leads?

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    Introduction: Metallic artifacts due to pacemaker/ implantable cardioverter defibrillator (ICD) leads in CT images can produce artifactual uptake in cardiac SPECT/CT images. The aim of this study was to determine the influence of the metallic artifacts due to pacemaker and ICD leads on myocardial SPECT/CT imaging. Methods: The study included 9 patients who underwent myocardial perfusion imaging (MPI). A cardiac phantom with an inserted solid defect was used. The SPECT images were corrected for attenuation using both artifactual CT and CT corrected using metal artifact reduction (MAR). VOI-based analysis was performed in artifactual regions. Results: In phantom studies, mean-of-relative-difference in white-region, between artifact-free attenuation-map without/with MAR were changed from 9.2 and 2.1 to 3.7 and 1.2 for ICD and pacemaker lead, respectively. However, these values for typical patient were 9.7±7.0 and 3.8±2.4 for ICD and pacemaker leads respectively, in white-region. MAR effectively reduces the artifacts in white-regions while this reduction is not significant in black-regions. Conclusion: Following application of MAR, visual and quantification analyses revealed that while quality of CT images were significantly improved, the improvements in the SPECT/CT images were not as pronounced or significant. Therefore cardiac SPECT images corrected for attenuation using CT in the presence of metallic-leads can be interpreted without correction for metal artefacts. © 2018 Tehran University of Medical Sciences. All rights reserved

    Nurses� perception of patient safety culture and its relationship with adverse events: a national questionnaire survey in Iran

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    Background: Patient safety culture is an important factor in determining hospitals� ability to address and reduce the occurrence of adverse events (AEs). However, few studies have reported on the impact of nurses� perceptions of patient safety culture on the occurrence of AEs. Our study aimed to assess the association between nurses� perception of patient safety culture and their perceived proportion of adverse events. Methods: A cross-sectional survey was carried out among 2295 nurses employed in thirty-two teaching hospitals in Iran. Nurses completed the Persian version of the hospital survey of patients� safety culture between October 2018 and September 2019. Results: Positive Response Rates of overall patient safety culture was 34.1 and dimensions of patient safety culture varied from 20.9 to 43.8. Also, nurses estimated that the occurrence of six adverse events varied from 51.2�63.0 in the past year. The higher nurses� perceptions of �Staffing�, �Hospital handoffs and transitions�, �Frequency of event reporting�, �Non-punitive response to error�, �Supervisor expectation and actions promoting safety�, �Communication openness�, �Organizational learning continuous improvement�, �Teamwork within units�, and �Hospital management support patient safety� were significantly related to lower the perceived occurrence at least two out of six AEs (OR = 0.69 to 1.46). Conclusions: Our findings demonstrated that nurses� perception regarding patient safety culture was low and the perceived occurrence of adverse events was high. The research has also shown that the higher level of nurses� perception of patient safety culture was associated with lowered occurrence of AEs. Hence, managers could provide prerequisites to improve patient safety culture and reduce adverse events through different strategies, such as encouraging adverse events� reporting and holding training courses for nurses. However, further research is needed to assess how interventions addressing patient safety culture might reduce the occurrence of adverse events. © 2021, The Author(s)

    Liposomal cytarabine as cancer therapy: From chemistry to medicine

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    Cancer is the second leading cause of death worldwide. The main modality to fight against cancer is surgery, radiotherapy, and chemotherapy, and more recently targeted therapy, gene therapy and immunotherapy, which play important roles in treating cancer patients. In the last decades, chemotherapy has been well developed. Nonetheless, administration of the drug is not always successful, as limited drug dosage can reach the tumor cells.. In this context, the possibility to use an encapsulated anti-cancer drug may potentially solve the problem. Liposomal cytarabine is a formulation with pronounced effectiveness in lymphomatous meningitis and reduced cardiotoxicity if compared to liposomal anthracyclines. Thus, the future liposomal cytarabine use could be extended to other diseases given its reduction in cytotoxic side effects compared to the free formulation. This review summarizes the chemistry and biology of liposomal cytarabine, with exploration of its clinical implications.N. Martins would like to thank the Portuguese Foundation for Science and Technology (FCT-Portugal) for the strategic project ref. UID/BIM/04293/2013 and "NORTE2020 - Programa Operacional Regional do Norte" (NORTE-01-0145-FEDER-000012). M. Martorell would like to thank the support offered by CONICYT PIA/APOYO CCTE AFB170007

    Parity Symmetry and Soft Limit for the Cachazo-Geyer Gravity Amplitude

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    In this note, we prove that the recent proposal for the tree-level n-particle N=8 supergravity amplitudes by Cachazo and Geyer satisfies parity symmetry and soft limit behavior expected for graviton scattering amplitudes
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