scholarly journals Using Torque-Angle and Torque–Velocity Models to Characterize Elbow Mechanical Function: Modeling and Applied Aspects

2019 ◽  
Vol 141 (8) ◽  
Author(s):  
Diane Haering ◽  
Charles Pontonnier ◽  
Nicolas Bideau ◽  
Guillaume Nicolas ◽  
Georges Dumont
Keyword(s):  
Human Movement ◽  
Velocity Model ◽  
Mathematical Function ◽  
Velocity Models ◽  
Physiological Values ◽  
The Mathematical Model ◽  
Torque Angle

Characterization of muscle mechanism through the torque-angle and torque–velocity relationships is critical for human movement evaluation and simulation. in vivo determination of these relationships through dynamometric measurements and modeling is based on physiological and mathematical aspects. However, no investigation regarding the effects of the mathematical model and the physiological parameters underneath these models was found. The purpose of the current study was to compare the capacity of various torque-angle and torque–velocity models to fit experimental dynamometric measurement of the elbow and provide meaningful mechanical and physiological information. Therefore, varying mathematical function and physiological muscle parameters from the literature were tested. While a quadratic torque-angle model seemed to increase predicted to measured elbow torque fitting, a new power-based torque–velocity parametric model gave meaningful physiological values to interpret with similar fitting results to a classical torque–velocity model. This model is of interest to extract modeling and clinical knowledge characterizing the mechanical behavior of such a joint.

scholarly journals Characterization of a New Chitosanase from a Marine Bacillus sp. and the Anti-Oxidant Activity of Its Hydrolysate

Marine Drugs ◽  
2020 ◽  
Vol 18 (2) ◽  
pp. 126
Author(s):  
Chunrui Ma ◽  
Xiao Li ◽  
Kun Yang ◽  
Shangyong Li
Keyword(s):  
Radical Scavenging ◽  
Maximal Activity ◽  
Hydroxyl Groups ◽  
Bacillus Sp ◽  
Low Molecular Weight Chitosan ◽  
Anti Oxidant

Chitooligosaccharide (COS) has been recognized to exhibit efficient anti-oxidant activity. Enzymatic hydrolysis using chitosanases can retain all the amino and hydroxyl groups of chitosan, which are necessary for its activity. In this study, a new chitosanase encoding gene, csnQ, was cloned from the marine Bacillus sp. Q1098 and expressed in Escherichia coli. The recombinant chitosanase, CsnQ, showed maximal activity at pH 5.31 and 60 °C. Determination of CsnQ pH-stability showed that CsnQ could retain more than 50% of its activity over a wide pH, from 3.60 to 9.80. CsnQ is an endo-type chitosanase, yielding chitodisaccharide as the main product. Additionally, in vitro and in vivo analyses indicated that chitodisaccharide possesses much more effective anti-oxidant activity than glucosamine and low molecular weight chitosan (LMW-CS) (~5 kDa). Notably, to our knowledge, this is the first evidence that chitodisaccharide is the minimal COS fragment required for free radical scavenging.

Generalization of traveltime inversion

Geophysics ◽  
1992 ◽  
Vol 57 (1) ◽  
pp. 9-14 ◽  
Author(s):  
Gérard C. Herman
Keyword(s):  
Time Windows ◽  
Velocity Model ◽  
Inversion Method ◽  
Nonlinear Inversion ◽  
Error Norm ◽  
Arrival Times ◽  
Traveltime Inversion ◽  
Velocity Models ◽  
Use Of Data

A nonlinear inversion method is presented, especially suited for the determination of global velocity models. In a certain sense, it can be considered as a generalization of methods based on traveltimes of reflections, with the requirement of accurately having to determine traveltimes replaced by the (less stringent and less subjective) requirement of having to define time windows around main reflections (or composite reflections) of interest. It is based on an error norm, related to the phase of the wavefield, which is directly computed from wavefield measurements. Therefore, the cumbersome step of interpreting arrivals and measuring arrival times is avoided. The method is applied to the reconstruction of a depth‐dependent global velocity model from a set of plane‐wave responses and is compared to other methods. Despite the fact that the new error norm only makes use of data having a temporal bandwidth of a few Hz, its behavior is very similar to the behavior of the error norm used in traveltime inversion.

scholarly journals Characterization of Parameters to Predict the Structural Behaviour of Geopolymeric Mortar Plates Strengthened with Carbon Fiber Reinforced Polymer

2014 ◽  
Vol 634 ◽  
pp. 485-497 ◽  
Author(s):  
Alfonso Pappalardo ◽  
Said Jalali ◽  
Felipe José Silva
Keyword(s):  
Carbon Fiber ◽  
Structural Engineering ◽  
Thin Plates ◽  
Experimental Program ◽  
Structural Behaviour ◽  
Pull Out ◽  
The Face ◽  
The Mathematical Model

This study includes the identification of parameters for the characterization of the structural behavior of thin plates composed of geopolymer mortars structured with bi-directional carbon fiber mesh. Initially, facade projects, designed by offices in São Paulo using the concepts of sustainable architecture, promoting the use of geopolymeric materials are presented. Then shows the composition of the geopolymer mortar used in this study and the characterization of their mechanical properties. As part of the experimental program, this study evaluates the plate bending behavior and the effect of pull-out test and push-off test of the metallic inserts. It has used the advanced features of ATENA computational mechanics program, which correspond to the state of the art in Finite Element Modeling of reinforced concrete structures, which allow the calibration of the mathematical model based on information from the experimental program. The numerical results showed satisfactory adhesion with the experimental results. It also has emphasized the importance of validation of these results on the determination of loads collapse of structural elements, as is reflected positively in the field of Structural Engineering in the face of increasing advancement of surface modeling programs and technological innovations in according to sustainability criteria for constructions materials.

Mitochondrial Neurogastrointestinal Encephalomyopathy (MNGIE): Biochemical Features and Therapeutic Approaches

2007 ◽  
Vol 27 (1-3) ◽  
pp. 151-163 ◽  
Author(s):  
M. C. Lara ◽  
M. L. Valentino ◽  
J. Torres-Torronteras ◽  
M. Hirano ◽  
R. Martí
Keyword(s):  
Molecular Genetic ◽  
In Vivo Studies ◽  
Gene Encoding ◽  
Mitochondrial Neurogastrointestinal Encephalomyopathy ◽  
Mtdna Replication ◽  
Biochemical Features

Over the last 15 years, important research has expanded our knowledge of the clinical, molecular genetic, and biochemical features of mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). The characterization of mitochondrial involvement in this disorder and the seminal determination of its genetic cause, have opened new possibilities for more detailed and deeper studies on the pathomechanisms in this progressive and fatal disease. It has been established that MNGIE is caused by mutations in the gene encoding thymidine phosphorylase (TP), which lead to absolute or nearly complete loss of its catalytic activity, producing systemic accumulations of its substrates, thymidine (dThd) and deoxyuridine (dUrd). Findings obtained from in vitro and in vivo studies indicate that the biochemical imbalances specifically impair mitochondrial DNA (mtDNA) replication, repair, or both leading to mitochondrial dysfunction. We have proposed that therapy for MNGIE should be aimed at reducing the concentrations of these toxic nucleosides to normal or nearly normal levels. The first treatment, allogeneic stem-cell transplantation (alloSCT) reported in 2006, produced a nearly full biochemical correction of the dThd and dUrd imbalances in blood. Clinical follow-up of this and other patients receiving alloSCT is necessary to determine whether this and other therapies based on a permanent restoration of TP will be effective treatment for MNGIE.

scholarly journals Joint interpretation of magnetotelluric, seismic, and well-log data in Hontomín (Spain)

Solid Earth ◽  
2016 ◽  
Vol 7 (3) ◽  
pp. 943-958 ◽  
Author(s):  
Xènia Ogaya ◽  
Juan Alcalde ◽  
Ignacio Marzán ◽  
Juanjo Ledo ◽  
Pilar Queralt ◽  
...  
Keyword(s):  
Seismic Data ◽  
Velocity Model ◽  
Unconsolidated Sediments ◽  
Well Log ◽  
Storage Site ◽  
Near Surface ◽  
Log Data ◽  
Velocity Models ◽  
Joint Interpretation

Abstract. Hontomín (N of Spain) hosts the first Spanish CO2 storage pilot plant. The subsurface characterization of the site included the acquisition of a 3-D seismic reflection and a circumscribed 3-D magnetotelluric (MT) survey. This paper addresses the combination of the seismic and MT results, together with the available well-log data, in order to achieve a better characterization of the Hontomín subsurface. We compare the structural model obtained from the interpretation of the seismic data with the geoelectrical model resulting from the MT data. The models correlate well in the surroundings of the CO2 injection area with the major structural differences observed related to the presence of faults. The combination of the two methods allowed a more detailed characterization of the faults, defining their geometry, and fluid flow characteristics, which are key for the risk assessment of the storage site. Moreover, we use the well-log data of the existing wells to derive resistivity–velocity relationships for the subsurface and compute a 3-D velocity model of the site using the 3-D resistivity model as a reference. The derived velocity model is compared to both the predicted and logged velocity in the injection and monitoring wells, for an overall assessment of the computed resistivity–velocity relationships. The major differences observed are explained by the different resolution of the compared geophysical methods. Finally, the derived velocity model for the near surface is compared with the velocity model used for the static corrections in the seismic data. The results allowed extracting information about the characteristics of the shallow unconsolidated sediments, suggesting possible clay and water content variations. The good correlation of the velocity models derived from the resistivity–velocity relationships and the well-log data demonstrate the potential of the combination of the two methods for characterizing the subsurface, in terms of its physical properties (velocity, resistivity) and structural/reservoir characteristics. This work explores the compatibility of the seismic and magnetotelluric methods across scales highlighting the importance of joint interpretation in near surface and reservoir characterization.

scholarly journals Development, in vitro and in vivo evaluations of novel lipid drug delivery system of Newbouldia laevis (P. Beauv.)

2016 ◽  
Vol 3 ◽  
pp. 184954351667344
Author(s):  
Chukwuebuka Umeyor ◽  
Emmanuel Anaka ◽  
Franklin Kenechukwu ◽  
Chinazom Agbo ◽  
Anthony Attama
Keyword(s):  
Encapsulation Efficiency ◽  
Folk Medicine ◽  
Research Work ◽  
Lipid Matrix ◽  
Solid Lipid ◽  
Development In Vitro

Newbouldia laevis (P. Beauv.) is a tropical rainforest plant used in traditional folk medicine for the treatment of malaria, cough, joint pains, stomach ache, oedema and inflammation. The main thrust of this research work was to study the analgesic/anti-nociceptive properties of N. laevis-loaded solid lipid microdispersions. N. laevis leaves were extracted using ethanol, and the extract was formulated into solid lipid microdispersions using lipid matrix comprising a rational blend of Precirol® ATO 5 and Softisan® 154. Characterization of the solid lipid microdispersions include determination of morphology, particle size, pH, thermal property, encapsulation efficiency percentage and analgesic/anti-nociceptive property. The results obtained showed that the particles were spherical with sizes ranging from 40 µm to 125 µm. The solid lipid microdispersions maintained a stable pH within the acidic region of 5–6 with insignificant variations ( p > 0.05) over a period of 90 days. Thermal analysis showed that N. laevis was entrapped in the lipid matrix used for the formulations. Solid lipid microdispersions recorded a maximum encapsulation efficiency up to 88.1%. N. laevis-loaded solid lipid microdispersions also produced good analgesic/anti-nociceptive property comparable with the standard diclofenac potassium. N. laevis-loaded solid lipid microdispersions showed good analgesic/anti-nociceptive effect and could be used in the treatment and management of pain.

scholarly journals Towards Polypharmacokinetics: Pharmacokinetics of Multicomponent Drugs and Herbal Medicines Using a Metabolomics Approach

2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Ke Lan ◽  
Guoxiang Xie ◽  
Wei Jia
Keyword(s):  
Molecular Mechanisms ◽  
Metabolic Response ◽  
Herbal Medicines ◽  
Multivariate Statistical ◽  
Vast Number ◽  
Wide Range ◽  
Viable Approach

Determination of pharmacokinetics (PKs) of multicomponent pharmaceuticals and/or nutraceuticals (polypharmacokinetics, poly-PKs) is difficult due to the vast number of compounds present in natural products, their various concentrations across a wide range, complexity of their interactions, as well as their complex degradation dynamicsin vivo. Metabolomics coupled with multivariate statistical tools that focus on the comprehensive analysis of small molecules in biofluids is a viable approach to address the challenges of poly-PK. This paper discusses recent advances in the characterization of poly-PK and the metabolism of multicomponent xenobiotic agents, such as compound drugs, dietary supplements, and herbal medicines, using metabolomics strategy. We propose a research framework that integrates the dynamic concentration profile of bioavailable xenobiotic molecules that result fromin vivoabsorption and hepatic and gut bacterial metabolism, as well as the human metabolic response profile. This framework will address the bottleneck problem in the pharmacological evaluation of multicomponent pharmaceuticals and nutraceuticals, leading to the direct elucidation of the pharmacological and molecular mechanisms of these compounds.

scholarly journals Simultaneous Determination of the Rates of the TCA Cycle, Glucose Utilization, α-Ketoglutarate/Glutamate Exchange, and Glutamine Synthesis in Human Brain by NMR

1995 ◽  
Vol 15 (1) ◽  
pp. 12-25 ◽  
Author(s):  
Graeme F. Mason ◽  
Rolf Gruetter ◽  
Douglas L. Rothman ◽  
Kevin L. Behar ◽  
Robert G. Shulman ◽  
...  
Keyword(s):  
Human Brain ◽  
Glucose Consumption ◽  
Tca Cycle ◽  
High Rate ◽  
Cycle Rate ◽  
The Tca Cycle ◽  
Glutamine Synthesis ◽  
Physiological Values

13C isotopic tracer data previously obtained by 13C nuclear magnetic resonance in the human brain in vivo were analyzed using a mathematical model to determine metabolic rates in a region of the human neocortex. The tricarboxylic acid (TCA) cycle rate was 0.73 ± 0.19 μmol min−1 g−1 (mean ± SD; n = 4). The standard deviation reflects primarily intersubject variation, since individual uncertainties were low. The rate of α-ketoglutarate/glutamate exchange was 57 ± 26 μmol min−1 g−1 ( n = 3), which is much greater than the TCA cycle rate; the high rate indicates that α-ketoglutarate and glutamate are in rapid exchange and can be treated as a single combined kinetic pool. The rate of synthesis of glutamine from glutamate was 0.47 μmol min−1 g−1 ( n = 4), with 95% confidence limits of 0.139 and 3.094 μmol min−1 g−1; individual uncertainties were biased heavily toward high synthesis rates. From the TCA cycle rate the brain oxygen consumption was estimated to be 2.14 ± 0.48 μmol min−1 g−1 (5.07 ± 1.14 ml 100 g−1 min−1; n = 4), and the rate of brain glucose consumption was calculated to be 0.37 ± 0.08 μmol min−1 g−1 ( n = 4). The sensitivity of the model to the assumptions made was evaluated, and the calculated values were found to be unchanged as long as the assumptions remained near reported physiological values.

scholarly journals Effects and Characterization of Some Topical Ointments Based on Vegetal Extracts on Incision, Excision, and Thermal Wound Models

Molecules ◽  
2020 ◽  
Vol 25 (22) ◽  
pp. 5356
Author(s):  
Calin Vasile Andritoiu ◽  
Corina Elena Andriescu ◽  
Constanta Ibanescu ◽  
Cristina Lungu ◽  
Bianca Ivanescu ◽  
...  
Keyword(s):  
Wistar Rats ◽  
Histopathological Examination ◽  
Contraction Rate ◽  
Thermal Burn ◽  
Arctium Lappa ◽  
Ointment Base ◽  
The One

The present paper aims to formulate and characterize four phytotherapeutic ointments based on Hippophae fructus, Calendulae flos, Bardanae folium, and Millefolii herba, which are included in a novel ointment base. In order to investigate the healing properties of the ointments, in vivo experimental wound models of linear incision, circular excision, and thermal burn were performed on Wistar rats. Topical treatment was performed daily for 21 days. Determination of the wound contraction rate (WCR), the period of reepithelization, and histopathological examination were achieved. Additionally, for the tested ointments, oscillatory and rotational rheological tests were carried out, and for the extracts, HPLC analysis was performed. The results demonstrate that the tested novel ointments are safe for use and the most effective ointment proved to be the one based on Arctium lappa, followed by that of Calendulae flos.

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