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Modulation of the in vitro Oxidative Stress and Erythrocyte Cell Membrane Integrity Using Aqueous, Hydroethanolic and Ethanolic Stem-Barks Extracts of Greenwayodendron suaveolens (Engl. & Diels) Verdc

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Pharmacology & Pharmacy 2024年第3期15卷 39-61页

作者： Patrick Hervé Diboue Betote Moustapha Gambo Abdoulaye Francis Ngolsou Esther Del Florence Ndedi Moni Adeline Sabine Fanta Yadang Fidel Castro Lah Weyepe gabriel A. Agbor Nga Nnanga Maximilienne Ascension Nyegue Laboratory of Pharmacology and Drugs Discovery Centre for Research on Medicinal Plants and Traditional Medicine Institute of Medical Research and Medicinal Plants Studies Yaoundé Cameroon Laboratory of Microbiology Department of Microbiology Faculty of Science University of Yaoundé I Yaoundé Cameroon Multidisciplinary Laboratory Department of Galenical Pharmacy and Pharmaceutical Law Faculty of Medicine and Biomedical Sciences University of Yaoundé I Yaoundé Cameroon Department of Physicochemical and Pharmaceutical Sciences Faculty of Health Sciences Abdou Moumouni University Niamey Niger Department of Pharmaceutical and Biological Sciences Faculty of Medicine and Pharmaceutical Sciences University of Douala Douala Cameroon Laboratory of Pharmaceutical Technology Centre for Research on Medicinal Plants and Traditional Medicine Institute of Medical Research and Medicinal Plants Studies Yaoundé Cameroon

Pneumonia, a respiratory infection induces acute or chronic inflammation, characterized by increased activity of lymphocytes and neutrophils, thus generating oxygen-free radicals that decrease the endogenous antioxidants defence system. The aim of this experimental study focused on the capacity of nontoxic aqueous, hydroethanolic and ethanolic extracts of Greenwayodendron suaveolens (Engl. & Diels) Verdc. subsp. suaveolens to regulate free reactive species and protein inflammation generated by infectious disease. The phytochemical screenings of G. suaveolens extracts were carried out according to precipitation and colorimetric methods. The total antioxidant and flavonoid contents were determined by the Folin-Ciocalteu and Aluminium Chloride ethanolic methods. The efficiency of G. suaveolens extracts on free radicals was evaluated using DPPH•, ABTS+•, and FRAP methods. The anti-inflammatory properties of extracts were evaluated according to in vitro protein (BSA) denaturation, Proteinase Inhibitory Action, and Red Blood Cell Membrane stabilization assays. The G. suaveolens aqueous, hydroethanolic and ethanolic extracts were used for the acute toxicity assessment according to the OECD protocol. The obtained results showed the presence of flavonoids, phenols, polyphenols, tannins, anthocyanins, alkaloids, terpenoids, and sterols as secondary metabolites families in G. suaveolens extracts. The highest contents of total antioxidants and flavonoids were highlighted in the hydroethanolic extract. However, it’s the G. suaveolens aqueous extract that showed the best free radical DPPH• and ABTS+• scavenging activities (SC50) of 11.06 μg/mL and 15.16 μg/mL respectively. The highest ferric-reducing activity was found in G. suaveolens ethanolic extract with 866.23 μg EGA/mg of dry weight. The hydroethanolic extract has shown a high anti-inflammatory activity through BSA denaturation and erythrocyte membrane haemolysis with i

关键词： Greenwayodendron suaveolens Secondary Metabolites Oxidative Stress Antioxidant Activity Anti-Inflammatory Properties and Oral Acute Toxicity

Numerical study of solar absorption heat storage system applied to Bucharest city

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Building Simulation 2021年第3期14卷 601-616页

作者： Noureddine Cherrad Adrian-gabriel Ghiaus University Kasdi Merbah ofOuargla Faculty of Applied SciencesDepartment of Mechanical EngineeringOuarglaAlgeria Doctoral School Technical University of Civil Engineering of BucharestBucharestRomania

Buildings represent a large part in terms of fossil energy consumption,which depends on the great need for *** if the solar absorption heat storage system is possible,the performance of this system is affected by the cycle limits and the climatic *** goal of the present study is to control the thermal performance of the system cycle according to the imposed climatic conditions of Bucharest city,Romania,and therefore a numerical model was developed for this *** scheme and the thermodynamic cycle,the energy and mass balance equations,and the computational algorithm were *** results show that the cycle temperature increases at the end of desorption when the heating power supplied to the desorber is increased,which is also proportional to the drop in temperature at the beginning of the *** temperature at the end of absorption and the mass flow rates of the solution have a significant effect on the thermal power released from the absorber and used to heat the *** an average daily heat power of 1.35 kW/m^(2) and 10 hours per day of heating the building,the system with a solar collector area of 3 m^(2) has the capacity of heat supply for all the cold ***,an economic strategy remains necessary.

关键词： numerical model absorption heat storage cycle temperatures climatic conditions

Selective and constructive mechanisms contribute to neural circuit formation in the barrel cortex of the developing rat

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Advances in Bioscience and Biotechnology 2013年第7期4卷 785-797页

作者： Eileen Uribe-Querol Eduardo Martínez-Martínez Luis Rodrigo Hernández Patricia Padilla Cortés Horacio Merchant-Larios gabriel gutiérrez-Ospinac Cell Biology and Physiology Department Instituto de Investigaciones Biomédicas Universidad Nacional Autónoma de México Mexico City Mexico División de Estudios de Posgrado e Investigación Facultad de Odontología Universidad Nacional Autónoma de México Mexico City Mexico Unidad de HPLC Instituto de Investigaciones Biomédicas Universidad Nacional Autónoma de México Mexico City Mexico

The cellular strategy leading to formation of neuronal circuits in the rodent barrel cortex is still a matter of controversy. Both selective and constructive mechanisms have been proposed. The selective mechanism involves an overproduction of neuronal processes and synapses followed by activity dependent pruning. Conversely, a constructive mechanism would increase the number of axons, dendrites, and synapses during development to match functionality. In order to discern the contributions of these two mechanisms in establishing a neuronal circuit in the somatosensory cortex, morphometric analysis of dendritic and axonal arbor growth was performed. Also, the number of synapses was followed by electron microscopy during the first month of life. We observed that axonal and dendritic arbors retracted distal branches, and elongated proximal branches, resulting in increased arbor complexity. This neuronal remodeling was accompanied by the steady increase in the number of synapses within barrel hollows. Similarly, the content of molecular markers for dendrites, axons and synapses also increased during this period. Finally, cytochrome oxidase activity rose with age in barrels indicating that the arbors became more complex while synapse density and metabolic demands increased. Our results support the simultaneous use of both selective and constructive mechanisms in establishing the barrel cortex circuitry.

关键词： Barrel Cortex Synaptogenesis Axonal Growth Dendritic Growth Thalamocortical Pathway

Modeling behaviors of a coal pillar rib using the progressive S-shaped yield criterion

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第3期12卷 484-492页

作者： Sankhaneel Sinha gabriel Walton Colorado School of Mines GoldenCO80401USA

Spalling of pillar ribs has been a major hazard in the mining industry for *** the absence of rib support guidelines,accidents have continued to occur in recent *** effective support guidelines requires a complete understanding of complex pillar damage *** models represent a convenient tool for analyzing this problem,but the behavior of such models is dependent of the choice of the constitutive *** this study,a recently proposed constitutive model was used to simulate the rib fracturing process in a longwall chain pillar at West Cliff *** calibration,the model was able to capture the rib displacement profiles for multiple locations of the longwall face and the stress evolution 4 m into the *** rib bolts in the model were found to be yielding over 60% of their length under the headgate loading *** model also predicted a steady damage accumulation in the rib for certain face locations,which is consistent with the description of the rib at the *** was localized along the upper part of the pillar and underscored the role that the dirt band played in controlling rib deterioration at the *** ability of the numerical model to replicate field measurements provides confidence in the capabilities of the new constitutive ***,the need of using multi-point calibration is highlighted by comparing the results of the calibrated model to an alternative model calibrated to a smaller amount of data.

关键词： S-shaped yield criterion Coal pillar Back-analysis Numerical modeling

Integration of three-dimensional continuum model and two-dimensional bonded block model for studying the damage process in a granite pillar at the Creighton Mine,Sudbury,Canada

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第2期13卷 275-288页

作者： Sankhaneel Sinha gabriel Walton Geology and Geological Engineering Colorado School of MinesGoldenCO80401USA

Bonded blockmodel(BBM)has shownpotential in replicating rockmass behavior aswell as the rockesupport interactionmechanism,but their practical application is limited totwo dimensions due to the high associated computational *** allow for the use of BBM in simulating three-dimensional(3D)problems,this study proposes an integrated 3D continuumetwo-dimensional(2D)discontinuum approach,in context of rock pillars.A cross-section of a granite pillar was simulated using a BBM with a load path from a calibrated mine-scale FLAC^(3D)*** support as employed in the mine was also incorporated in different stages during the *** was calibrated by varying the input parameters until the displacements at six locations within the pillarmatchedthosemeasuredby amulti-point borehole extensometer(MPBX)inthe *** calibratedmodel was subsequently used to understand how the support and load path influenced the damage evolution in the *** shear component of the load pathwas found to have amajor effect on the severity and extent of the damaged *** the support density was increased in the model,the lateral displacements along the pillar walls were significantly suppressed in a somewhat unpredictable *** explained by the interaction between the supports and the damaged regions at the corners,which ultimately modified the stresses along the pillar *** amount of displacement reduction obtained by increasing the support density illustrates the potential of BBMto be used as a support design tool.

关键词： Bonded block model(BBM) Rock pillars Supports Continuum-discontinuum integration

Challenges associated with numerical back analysis in rock mechanics

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第6期14卷 2058-2071页

作者： gabriel Walton Sankhaneel Sinha Department of Geology and Geological Engineering Colorado School of MinesGoldenCO80401USA

Numerical back analysis is a valuable tool available to rock mechanics researchers and *** studies related to back analysis methods focused primarily on applications of increasingly sophisticated optimization algorithms(primarily machine learning algorithms)to rock mechanics *** methods have typically been applied to relatively simple problems;however,more complex back analyses continue to be conducted primarily through ad hoc manual trial-and-error *** paper provides a review of the basic concepts and recent developments in the field of numerical back analysis for rock mechanics,as well as some discussion of the relationship between back analysis and more broadly established frameworks for numerical *** challenges of flexible constraints,non-uniqueness,material model limitations,and disparate data sources are considered,and representative case studies are presented to illustrate their impacts on back *** role of back analysis(or“model calibration”)in bonded particle modelling(BPM),bonded block modelling(BBM),and synthetic rock mass(SRM)modelling is also considered,and suggestions are made for further studies on this topic.

关键词： Back analysis Numerical modelling Inversion Case studies

Modelling fuel loads of understorey vegetation and forest floor components in pine stands in NW Spain

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Forest Ecosystems 2022年第6期9卷 775-789页

作者： Jose A.Vega Stefano Arellano-Perez Juan gabriel Alvarez-Gonzalez Cristina Fernandez Enrique Jimenez Pedro Cuinas Jose María Fernandez-alonso Daniel J.Vega-Nieva Fernando Castedo-Dorado Cecilia alonso-Rego Teresa Fontúrbel Ana Daría Ruiz-Gonzalez Centro de Investigacion Forestal de Lourizan PO Box 12736080PontevedraSpain Unidad de Gestion Ambiental y Forestal Sostenible(UXAFORES) Departamento de Ingeniería AgroforestalEscuela Politecnica Superior de IngenieríaUniversidad de Santiago de CompostelaCampus Universitario s/n27002LugoSpain Facultad de Ciencias Forestales Universidad Juarez del Estado de DurangoRío Papaloapan y Blvd.Durango s/nCol.Valle del Sur34120DurangoMexico Departamento de Ingeniería y Ciencias Agrarias Universidad de LeonCampus de Ponferrada24401PonferradaSpain

In this study,310 destructively sampled plots were used to develop two equation systems for the three main pine species in NW Spain(***;*** and ***):one for estimating loads of understorey fuel components by size and condition(live and dead)and another one for forest floor *** systems of equations were simultaneously fitted for estimating fuel loads using overstorey,understorey and forest floor variables as *** systems of equations included both the effect of pine species and the effect of understorey compositions dominated by ferns-brambles or by woody species,due to their obvious structural and physiological *** general,the goodness-of-fit statistics indicated that the estimates were reasonably robust and accurate for all of the fuel *** best results were obtained for total understorey vegetation,total forest floor and raw humus fuel loads,with more than 76%of the observed variability explained,whereas the poorest results were obtained for coarse fuel loads of understory vegetation with a 53%of observed variability *** reduce the overall costs associated with the field inventories necessary for operational use of the models,the additive systems were fitted again using only overstorey variables as potential *** relationships for fine(<6 mm)and total understorey vegetation and total forest floor fuel loads were obtained,indicating the complexity of the forest overstorey-understorey and overstorey-forest floor ***,these models explained around 52%of the observed ***,equations estimating the total understorey vegetation and the total forest floor fuel loads based only on canopy cover were *** models explained only 26%-32%of the observed variability;however,their main advantage is that although understorey vegetation in forested landscapes is largely invisible to remote sensing,canopy cover can be estimated with moderate accuracy,allowin

关键词： Area-based approach Additive equation systems Live and dead fine fuel Pinus pinaster Pinus radiata Pinus sylvestris

Effect of music therapy on short-term psychological and physiological outcomes in mechanically ventilated patients:A randomized clinical pilot study

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Journal of Intensive Medicine 2024年第4期4卷 515-525页

作者： Mark Ettenberger Rosangela Casanova-Libreros Josefina Chávez-Chávez Jose gabriel Cordoba-Silva William Betancourt-Zapata Rafael Maya Lizeth Alexa Fandino-Vergara Mario Valderrama Ingrid Silva-Fajardo Sandra Milena Hernández-Zambrano SONO-Centro de Musicoterapia BogotáColombia Vice-Rectorate for Research Fundación Universitaria de Ciencias de la SaludBogotáColombia Department of Biomedical Engineering University of Los AndesBogotáColombia Department of Rehabilitation Sociedad de Cirugía de Bogotá Hospital de San JoséBogotáColombia Faculty of Nursing Fundación Universitaria de Ciencias de la SaludBogotáColombia

Background:Elevated anxiety levels are common in patients on mechanical ventilation(MV)and may challenge *** suggests music-based interventions may reduce anxiety during ***,studies inves-tigating specific music therapy techniques,addressing psychological and physiological well-being in patients on MV,are ***:This three-arm randomized clinical pilot study was conducted with MV patients admitted to the intensive care unit(ICU)of Hospital San Joséin Bogotá,Colombia between March 7,2022,and July 11,*** were divided into three groups:intervention group 1(IG1),music-assisted relaxation;intervention group 2(IG2),patient-preferred therapeutic music listening;and control group(CG),standard *** main outcome measure was the 6-item State-Anxiety *** outcomes were:pain(measured with a visual analog scale),resilience(measured with the Brief Resilience Scale),agitation/sedation(measured with the Richmond Agitation-Sedation Scale),vital signs(including heart rate,blood pressure,oxygen saturation,and respiratory rate),days of MV,extubation success,and days in the ***,three patients underwent electroencephalography during the ***:Data from 23 patients were analyzed in this *** age range of the patients was 24.0-84.0 years,with a median age of 66.0 years(interquartile range:57.0-74.0).Of the 23 patients,19 were female(82.6%).No statistically significant differences between the groups were observed for anxiety(P=0.330),pain(P=0.624),resilience(P=0.916),agitation/sedation(P=0.273),length of ICU stay(P=0.785),or vital signs.A statistically significant difference between the groups was found for days of MV(P=0.019).Electroencephalography mea-surements showed a trend toward delta and theta band power decrease for two patients and a power increase on both beta frequencies(slow and fast)in the frontal areas of the brain for one ***:In this pilot study,music therapy did not sig

关键词： Music therapy Mechanical ventilation Intensive care unit Anxiety Pain

Understanding roof deformation mechanics and parametric sensitivities of coal mine entries using the discrete element method

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International Journal of Mining Science and Technology 2020年第1期30卷 123-129页

作者： Rami Abousleiman gabriel Walton Sankhaneel Sinha Department of Geology and Geological Engineering Colorado School of MinesGoldenCO 80218USA

Although conventional coal mine designs are conservative regarding pillar strength,local failures such as roof-falls and pillar bursts still affect mine safety and *** studies have identified that discontinuous,layered roof materials have some self-supporting *** research is a preliminary step towards understanding these mechanics in coal-measure *** others have considered broad conceptual models and simplified analogs for mine roof behavior,this study presents a unique numerical model that more completely represents in-situ roof *** discrete element method(DEM)is utilized to conduct a parametric analysis considering a range of in-situ stress ratios,material properties,and joint networks to determine the parameters controlling the stability of single-entries modeled in *** results are compared to empirical observations of roof-support effectiveness(ARBS)in the context of the coal mine roof rating(CMRR)*** such as immediate roof displacement,overall stability,and statistical relationships between model parameters and outcomes are presented *** practical applications of this line of research include:(1)roof-support optimization for a range of coal-measure rocks,(2)establishment of a relationship between roof stability and pillar stress,and(3)determination of which parameters are most critical to roof stability and therefore require concentrated evaluation.

关键词： Numerical modeling Discrete element method Coal mine roof rating Analysis of roof bolt systems Sensitivity analysis Strain softening ubiquitous joints Discrete fracture network