47 research outputs found

    Zoledronic Acid and Survival in Patients with Metastatic Bone Disease From Lung Cancer and Elevated Markers of Osteoclast Activity: A Novel Molecular Mechanism

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    Gentamicin-attenuated leishmania infantum vaccine: protection of dogs against canine visceral leishmaniosis in endemic area of southeast of Iran

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    An attenuated line of Leishmania infantum (L. infantum H-line) has been established by culturing promastigotes in vitro under gentamicin pressure. A vaccine trial was conducted using 103 naive dogs from a leishmaniosis non-endemic area (55 vaccinated and 48 unvaccinated) brought into an endemic area of southeast Iran. No local and/or general indications of disease were observed in the vaccinated dogs immediately after vaccination. The efficacy of the vaccine was evaluated after 24 months (4 sandfly transmission seasons) by serological, parasitological analyses and clinical examination. In western blot analysis of antibodies to L. infantum antigens, sera from 10 out of 31 (32.2%) unvaccinated dogs, but none of the sera from vaccinated dogs which were seropositive at >100, recognized the 21 kDa antigen of L. infantum wild-type (WT). Nine out of 31 (29%) unvaccinated dogs, but none of vaccinated dogs, were positive for the presence of Leishmania DNA. One out of 46 (2.2%) vaccinated dogs and 9 out of 31 (29%) unvaccinated dogs developed clinical signs of disease. These results suggest that gentamicin-attenuated L. infantum induced a significant and strong protective effect against canine visceral leishmaniosis in the endemic area

    Chattering-Free Robust Adaptive Sliding Mode Speed Control for Switched Reluctance Motor

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    This study describes an adaptive sliding mode control (ASMC) for the control of switched reluctance motor (SRM). The main objective is to minimize torque ripples with controller effort smoothness while the system is under perturbation by structured uncertainties, unknown parameters, and external disturbances. The control algorithm employs an adaptive approach to remove the need for prior knowledge within the bound of perturbations. This is suitable for tackling the chattering problem in the sliding motion of ASMC. In order to achieve control effort smoothness and more effective elimination of chattering, the algorithm then incorporates proper modifications in order to build a chattering-free robust adaptive sliding mode control (RASMC) using Lyapunov stability theory. A final advantage of the algorithm is that system stability and error convergence are guaranteed. The effectiveness of the proposed controller in improving robustness and minimizing ripples is demonstrated by numerical simulation. Experimental validation is used to demonstrate the efficiency of the proposed scheme. The results indicate that RASMC provides a superior performance with respect to speed tracking and disturbance rejection over the conventional sliding mode control (CASMC) in the face of uncertainties in model and dynamic loads

    Stabilization of DC–DC buck converter with unknown constant power load via passivity-based control plus proportion-integration

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    Abstract It is known that constant power load (CPL) may cause a negative impedance, which seriously affects the stability of power system. In this paper, a new control algorithm for DC–DC buck converter feeding unknown CPL is proposed. First, under the assumption of known extracted power load, the standard passivity–based control (PBC) is presented to reshape the system energy and compensate for the negative impedance and a proportion‐integration (PI) action around passive output is added to improve disturbance rejection performance, which forms the PBC plus PI (PBC+PI). Then, a parameter estimation algorithm is developed, based on immersion and invariance (I&I) technique, in order to online estimate the extracted power load. In the next step, the online estimation scheme is adopted to construct an adaptive strategy. Finally, the stability analysis of the cascaded system containing a closed‐loop control system and observer error dynamics is conducted. Simulation and experimental results are demonstrated to validate the performance of the proposed controller

    Evaluation of Various Fixation Methods in Acute Scapholunate Dissociation, A Finite Element Study

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    Objective: This study aimed to compare the outcomes of fixing scapholunate with pins and screws in parallel,convergent, and divergent orientations.Methods: In this computer simulation study, the CT scan images of a healthy subject wereused to construct a 3D model of the wrist joint using MIMICS software. The imposed force to scaphoid and3D model lunate bones, as well as the scapholunate angle and distance, were compared in different surgicaltechniques using parallel, divergent, and convergent pins and screws.Results: In the absence of external force, the imposed stress applied to the scaphoid and lunate bones in casesof parallel pins and screws were 7.5MPa, 5.08MPa (pins), 1.134MPa, and 1.151MPa (screws), and 10.90MPa,10.90MPa (pins), 9.7MPa, and 34.1MPa (screws) for 50N flexion force. The imposed stress in this approach issignificantly lower compared to other interventions. Better outcomes were seen regarding scapholunate angleand scapholunate distance in using parallel pins or screws as well.Conclusion: In conclusion, implementing parallel pins and screws for scapholunate fixation had better resultsin terms of achieving carpal stability in scapholunate dissociation. However, fixation with pins and screwsshowed a statistically significant difference. Furthermore, a wide range of motion exercises with no additionalforces can be used in the rehabilitation of patients undergoing this surgery

    Chronic Total Occlusion-Angioplasty with Antegrade Approach: A two-Year Experience in “Modarres Hospital”, A Tertiary University Hospital, Tehran, Iran

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    Introduction: New techniques for the percutaneous treatment of coronary chronic total occlusions (CTO) have had a high success rate since a few years ago, so the interest for this treatment has been increasing these days.Methods: The current observational study was performed in Modarres hospital as a tertiary referral center. All the patients with documented stable angina who had failed to response to full guideline-mediated medical therapy, referred to our hospital, were candidates for coronary angiography. Antegrade strategy was applied for all these patients. The length of the lesion, the fluoroscopy time of the CTO angioplasty, consumed contrast volume, the number of guide wires used, whether a corsair or tornus micro-catheter was used or not, and the success rate of the angioplasty were documented for further analysis.Results: A total of 47 patients with documented stable angina were finally included. The median age was 59 (45-78) and 70.2% were male. The mean length of the lesion was 34.0 ± 1.1 .The mean fluoroscopy time and contrast volume were 57.9 ± 3.2 minutes and 525.9 ± 20.9 mL, respectively. In average, 2.2 guide wires were used. Corsair and tornus micro-catheters were applied in 30 (63.8%) and 5 (10.6%) of the cases, respectively. Seven complications (all including coronary dissection) occurred. In-hospital major adverse cardiac events (MACE) rate was 10.6%, all of which were non-Q wave myocardial infarction. The success rate was 85.1%. The higher number of used wires, use of corsair, and tornus micro-catheter were not significantly concordant with success rate (P-value > 0.05); in addition, longer lesion was not concordant with unsuccessfulness rate (P-value > 0.05).Conclusions: Patient selection for CTO-angioplasty should be performed more carefully. Patients’ quality of life and risk of probable procedural complications and future cardiac events should be assessed to decide the best treatment approach. Radiation exposure, contrast consumption and fluoroscopy time are recommended to be monitored during the procedure and thresholds should be defined to enhance safety and efficacy

    The Comparison of Biomechanical Volar and Dorsal Plating in Distal Part Radius Fractures; a Finite Element Analysis Study

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    Objective: To compare the stability of the radius stabilized fractured parts by volar and dorsal planting based on modeling approach. Methods: Ten forearm models were created based on Computed Tomography (CT) Scan images by using of Mimics software. The distal part fracture of radius was induced in the models. The stress were developed and implanted in various parts of the bone and and their displacement were evaluated in volar and dorsal inserted implants. Results: The results of this study showed that the stress developed in screws, implant and bony parts differed significantly between volar and dorsal plate conditions. The displacement of implant and bony parts in volar plating was more than dorsal plating (p=0.05). However, the screws displacement in dorsal plating significantly increased compared to volar plating. Conclusion: The stress developed in dorsal and volar implants is not too high to fail the structure. However, it seems that the irritation of soft tissue and tendon would be less in volar inserted implant than dorsal implant. It is recommended to use valor plating to be a good approach for stabilizing the distal part fracture of radius

    COVID-19 related stigma among the general population in Iran

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    Funding Information: GT is supported by the National Institute for Health Research (NIHR) Applied Research Collaboration South London at King’s College London NHS Foundation Trust, and by the NIHR Asset Global Health Unit award. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care. GT is also supported by the Guy’s and St Thomas’ Charity for the On Trac project (EFT151101), and by the UK Medical Research Council (UKRI) in relation to the Emilia (MR/S001255/1) and Indigo Partnership (MR/R023697/1) awards. Publisher Copyright: © 2022, The Author(s).Peer reviewedPublisher PD
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