scholarly journals Influence of Cable Lengths on EMI Emissions of a DC/DC Converter

2020 ◽  
Vol 93 (1-4) ◽  
pp. 26-30
Author(s):  
Baghdadi Benazza ◽  
Abdelber Bendaoud ◽  
Jean-Luc Schanen
Keyword(s):  
Experimental Model ◽  
Buck Converters ◽  
Common Mode ◽  
Electromagnetic Pollution ◽  
The Impact

The aim of this study is to evaluate the influence of the position of a DC/DC static converter between a source and a load with regard to the conducted EMC emissions measured on the source. An experimental model was established through the analysis of relevant stresses, such as the variation in the lengths of the source-converter, converter-load cables and the impact of the shield connection. Through this study, it was observed that the circuit was sensitive to too large variations in the capacities of common mode and of the link, and the results obtained make it possible to confirm the reality of the electromagnetic pollution of the static DC/DC converter "Buck" as a function of connections. The results of this research can be used in DC/DC network designs based on buck converters.

Performance and Loads of a Lift Offset Rotor, Part II: Prediction Validations with Measurements

2021 ◽  
Author(s):  
Joseph H. Schmaus ◽  
Inderjit Chopra
Keyword(s):  
Experimental Model ◽  
Comprehensive Analysis ◽  
Rotor Part ◽  
Pitch Bearing ◽  
The Impact

The predictions of an upgraded UMARC comprehensive analysis are compared to experimental lift offset rotor results. The experiments cover a range of collective pitch angles (θ°) from 2° to 10°, advance ratios (μ) from 0.21 to 0.53, and lift offset from 0% to 20%. The experimental model rotors are from a system of coaxial hingeless rotors, with two blades each, and a first flap frequency of approximately 1.6/rev. The simulation is compared with isolated rotor performance and controls with lift offset, loads, and pitch link forces. Increasing efficiency with increasing lift offset, the impact of lift offset on different loads, and the dependence of pitch link loads on pitch bearing damping are identified in the experiment and correlated with the simulation.

scholarly journals Deletion of arginase 2 attenuates neuroinflammation in an experimental model of optic neuritis

PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0247901
Author(s):  
Amritha A. Candadai ◽  
Fang Liu ◽  
Abdelrahman Y. Fouda ◽  
Moaddey Alfarhan ◽  
Chithra D. Palani ◽  
...  
Keyword(s):  
Optic Neuritis ◽  
Experimental Model ◽  
Axonal Degeneration ◽  
Wild Type ◽  
Autoimmune Encephalomyelitis ◽  
Optic Nerves ◽  
Clinical Presentations ◽  
Retinal Neurodegeneration ◽  
The Impact ◽  
Experimental Autoimmune

Vision impairment due to optic neuritis (ON) is one of the major clinical presentations in Multiple Sclerosis (MS) and is characterized by inflammation and degeneration of the optic nerve and retina. Currently available treatments are only partially effective and have a limited impact on the neuroinflammatory pathology of the disease. A recent study from our laboratory highlighted the beneficial effect of arginase 2 (A2) deletion in suppressing retinal neurodegeneration and inflammation in an experimental model of MS. Utilizing the same model, the present study investigated the impact of A2 deficiency on MS-induced optic neuritis. Experimental autoimmune encephalomyelitis (EAE) was induced in wild-type (WT) and A2 knockout (A2-/-) mice. EAE-induced cellular infiltration, as well as activation of microglia and macrophages, were reduced in A2-/- optic nerves. Axonal degeneration and demyelination seen in EAE optic nerves were observed to be reduced with A2 deletion. Further, the lack of A2 significantly ameliorated astrogliosis induced by EAE. In conclusion, our findings demonstrate a critical involvement of arginase 2 in mediating neuroinflammation in optic neuritis and suggest the potential of A2 blockade as a targeted therapy for MS-induced optic neuritis.

scholarly journals Electromagnetic Pollution as a Possible Explanation for the Decline of House Sparrows in Interaction with Other Factors

Birds ◽  
2021 ◽  
Vol 2 (3) ◽  
pp. 329-337
Author(s):  
Alfonso Balmori
Keyword(s):  
Electromagnetic Radiation ◽  
Thermal Effects ◽  
House Sparrow ◽  
Bird Species ◽  
Passer Domesticus ◽  
The Other ◽  
Rapid Decline ◽  
House Sparrows ◽  
Electromagnetic Pollution ◽  
The Impact

In recent decades, there has been a decline of the House Sparrow (Passer domesticus), mainly in European cities, and several hypotheses have been proposed that attempt to determine the causes of this rapid decline. Previous studies indicated that house sparrows were significantly negatively associated with increasing electromagnetic radiation and sparrows disappeared from areas most polluted. In addition, there are many studies on the impact of radiation on other bird and non-bird species, as well as numerous laboratory studies that demonstrated detrimental effects at electric field strength levels that can be found in cities today. Electromagnetic radiation is the most plausible factor for multiple reasons, including that this is the only one that affects the other hypotheses proposed so far. It is a type of pollution that affects productivity, fertility, decreases insects (chicken feed), causes loss of habitat, decreases immunity and can promote disease. Additionally, the recent sparrow decline matches the deployment of mobile telephony networks. Further, there are known mechanisms of action for non-thermal effects of electromagnetic radiation that may affect sparrows causing their decline. Thus, electromagnetic radiation must be seriously considered as a factor for house sparrows’ decline, probably in synergy with the other factors previously proposed.

The impact of naloxegol treatment on gastrointestinal transit and colonic volume

2017 ◽  
Vol 16 (1) ◽  
pp. 172-172
Author(s):  
D. Grønlund ◽  
A.E. Olesen ◽  
J.L. Poulsen ◽  
C. Brock ◽  
A.M. Drewes
Keyword(s):  
Experimental Model ◽  
Transit Time ◽  
Gastrointestinal Transit ◽  
Receptor Activation ◽  
Opioid Antagonist ◽  
Imaging Method ◽  
Transit System ◽  
Gi Symptoms ◽  
Gi Transit ◽  
The Impact

Abstract Aims Opioid treatment is associated with gastrointestinal (GI) side effects, known as opioid-induced bowel dysfunction (OIBD). Symptoms of OIBD are caused by opioid receptor activation in the enteric nervous system, which results in increased GI transit time and increased faecal volume in the colon. OIBD can be experimentally induced in healthy participants through oral oxycodone treatment. The aim of this study was to investigate whether administration of naloxegol, a peripherally restricted opioid antagonist, could reduce GI symptoms, GI transit time, and colorectal volume, using an experimental model of OIBD. Methods In a double blind crossover trial, twenty-five healthy males were randomly assigned to a six day treatment of oral oxycodone in combination with either oral naloxegol or placebo. At baseline and at day six, participants filled in the Patient Assessment of Constipation Symptom questionnaire, and colorectal volume was quantified with a magnetic resonance imaging method. Participants swallowed a small electromagnetic capsule, which allowed determination of total and segmental GI transit times, using the 3D-Transit system. Results In the established model of oxycodone induced OIBD, fewer GI symptoms were observed during naloxegol treatment, compared to placebo (P <0.01). Naloxegol decreased median total transit time by 27% (56 vs 71 h, P < 0.05) and decreased colorectal transit time by 33% (45 vs 59 h, P < 0.01), compared to placebo. No difference in colorectal volume was found between the two treatments. Conclusions In an experimental model of OIBD, GI symptoms and GI transit time were reduced during treatment with naloxegol, compared to placebo. However, naloxegol treatment did not reduce colorectal volume. These findings add information on the potential of naloxegol to be used in prevention and treatment of OIBD.

Abstract 401: Experimental Aneurysm in Rats Excluded by Stent Graft: A New Model to Assess the Impact of Endovascular Aneurysm Repair on the Pathophysiology of Abdominal Aortic Aneurysm.

2012 ◽  
Vol 32 (suppl_1) ◽  
Author(s):  
Martin Rouer ◽  
Martin Rouer ◽  
Jean-Marc Alsac ◽  
Jean-Baptiste Michel
Keyword(s):  
Experimental Model ◽  
Ex Vivo ◽  
Endovascular Aneurysm Repair ◽  
Small Animal ◽  
Normal Diet ◽  
Biological Study ◽  
Experimental Aneurysm ◽  
Midline Laparotomy ◽  
The Impact

Introduction Biological study of the impact of endovascular aortic repair (EVAR) on pathophysiology of aortic abdominal aneurysms (AAA) can only be performed indirectly in humans, by imaging or search for peripheral biomarkers in the circulating blood. Therefore biological mechanism’s modifications into the aneurismal wall related to its endovascular exclusion are still to be elucidated, and small animal models should bring a valuable help in this field. We describe a new experimental model of stentgraft implantation for the exclusion of AAA in rats. Methods Aneurysms were induced as previously described by intra-aortic elastase injection in Wistar rats, or by aortic decellularized xenograft transplantation in Lewis rats. At least 15 days later, the midline laparotomy was reopened, and 3mm covered stentgraft were inserted and deployed in the AAA to obtain its exclusion. The patency of the graft and the AAA exclusion could be assessed by a global arteriogram through the carotid artery. After closure of the laparotomy, the rats were awakened and returned to a normal diet. Results This experimental model of AAA exclusion by a stentgraft allows many in vivo and ex vivo studies of the pathophysiology of AAA after EVAR. Histological modifications of the aortic wall and the intra-luminal thrombus could be assessed. The impact of EVAR on the adventitial immuno-inflammatory activity could be studied by different imaging such as MRI, scintigraphy or PET-scan. In situ biological and enzymatic activities could be evaluated to better understand the local mechanisms leading to AAA shrinkage or expansion after EVAR. Conclusion Exclusion by stentgraft of experimental AAA in rats is the first described model of EVAR in small animals. It is feasible and reproducible for both elastase and xenograft experimental AAA models. This model will definitely help to a better analysis and understanding of the impact of stentgrafting on biological mechanisms in the aneurismal wall, that lead to EVAR success with shrinkage of aneurismal sac or EVAR failure with its continuing expansion.

scholarly journals Numerical analysis of the impact of removing a corner column in a continuous slab-column structure in relation to the experimental model

2020 ◽  
Vol 310 ◽  
pp. 00054
Author(s):  
Miroslaw Wieczorek
Keyword(s):  
Numerical Analysis ◽  
Numerical Modelling ◽  
Experimental Model ◽  
Experimental Research ◽  
Experimental Results ◽  
Numerical Calculations ◽  
Column Structure ◽  
Continuous Slab ◽  
The Impact ◽  
Model Support

The paper presents the numerical analysis of the impact of removing a corner column on the behavior of a continuous slab-column structure. The model uses the minimal reinforcement amount compliant with Eurocodes. The basis for numerical modelling was the experimental research of a piece of a slab-column structure with the dimensions of 3.0×3.0 m in column axes. The article includes a detailed description of the assumed conditions of the model support, the method of loading and reading of the results. The paper also compares the obtained results of numerical calculations with experimental results.

scholarly journals The impact of the competence quorum sensing system on Streptococcus pneumoniae biofilms varies depending on the experimental model

2011 ◽  
Vol 11 (1) ◽  
pp. 75 ◽  
Author(s):  
Claudia Trappetti ◽  
Luciana Gualdi ◽  
Lorenzo Di Meola ◽  
Prashant Jain ◽  
Cindy C Korir ◽  
...  
Keyword(s):  
Streptococcus Pneumoniae ◽  
Quorum Sensing ◽  
Experimental Model ◽  
Sensing System ◽  
Quorum Sensing System ◽  
The Impact

scholarly journals Common mode behavior in grid connected DC and AC decoupled PV Inverter topologies

2016 ◽  
Vol 65 (3) ◽  
pp. 481-493 ◽  
Author(s):  
D. John Sundar ◽  
M. Senthil Kumaran
Keyword(s):  
Leakage Current ◽  
High Efficiency ◽  
Economic Feasibility ◽  
Photovoltaic Systems ◽  
Common Mode ◽  
Pv Inverter ◽  
Mode Behavior ◽  
The Common ◽  
Utility Grid ◽  
The Impact

Abstract The transformer-less grid connected inverters are gaining more popularity due to their high efficiency, very low ground leakage current and economic feasibility especially in photovoltaic systems. The major issue which surfaces these systems is that of common mode leakage current which arises due to the absence of an electrical transformer connected between the inverter and the utility grid. Several topologies have evolved to reduce the impact of common mode leakage current and a majority of them have succeeded in eliminating the impacts and have well kept them within the limits of grid standards. This paper compares and analyses the impact of the common mode leakage current for four popular inverter configurations through simulation of the topologies such as H5, H6, HERIC and FBZVR inverters.

Sign in / Sign up

Export Citation Format

Share Document