Search results for "reduction"

showing 10 items of 2058 documents

Biochemistry and pharmacology of novel anthranilic acid derivatives activating heme-oxidized soluble guanylyl cyclase.

2005

The heme-enzyme soluble guanylyl cyclase (sGC) is an ubiquitous NO receptor, which mediates NO downstream signaling by the generation of cGMP. We studied the mechanism of action of the anthranilic acid derivatives 5-chloro-2-(5-chloro-thiophene-2-sulfonylamino-N-(4-(morpholine-4-sulfonyl)-phenyl)-benzamide sodium salt (HMR1766) (proposed international nonproprietary name, ataciguat sodium) and 2-(4-chloro-phenylsulfonylamino)-4,5-dimethoxy-N-(4-(thiomorpholine-4-sulfonyl)-phenyl)-benzamide (S3448) as a new class of sGC agonists. Both compounds activated different sGC preparations (purified from bovine lung, or crude from human corpus cavernosum) in a concentration-dependent and quickly reve…

Vasodilator AgentsBlood PressureHemePharmacologychemistry.chemical_compoundEnzyme activatorAnthranilic acidmedicineCyclic GMP-Dependent Protein KinasesAnimalsortho-AminobenzoatesReceptorHemePharmacologySulfonamidesProtoporphyrin IXActivator (genetics)Enzyme ActivationchemistryMechanism of actionBiochemistryGuanylate CyclaseMolecular MedicineCattlemedicine.symptomSoluble guanylyl cyclaseOxidation-ReductionMolecular pharmacology
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Practical Implementation of a Synchronous PWM Strategy for Low Switching Frequency FOC of im Drives with ATSAM3X8E Microcontroller

2021

This paper presents a practical implementation of synchronous PWM modulation algorithm for an induction motor field oriented control powered by a DC/AC inverter and implemented on a low-cost microcontroller, the ATSAM3X8E. In particular, a simple algorithm, capable to calculate automatically an optimized set of frequency modulation indexes will be presented. Hysteresis bands are also introduced in the algorithm in order to avoid multiple changeovers during modulation index transitions. Experimental tests and their results will be shown and discussed, highlighting the benefits of the present algorithm, such as reduction of current harmonic content, reduction of current ripple and, consequent…

Vector controlcurrent rippleComputer sciencesynchronous/asynchronous PWMModulation indexVSISettore ING-IND/32 - Convertitori Macchine E Azionamenti ElettriciReduction (complexity)harmonicselectric drivesHarmonicElectronic engineeringInverterFrequency modulationPulse-width modulationInduction motor
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Transdermal Nitroglycerine Patch: An Optional Device to Reduce Flap Venous Congestion? A Case Report

2013

ABSTRACT Sometimes in free flap there is a venous congestion without an obstruction of the venous anastomosis or other organic causes of reduction venous drainage (haematoma, seroma compressing the pedicle). In these cases the authors suggest the application of nitroglycerine patch in the congested area of the flap few hours before the surgical exploration of the anastomosis. If there is a fast improvement of the clinical feature of the flap, the surgical exploration could be avoided. The authors underline that applying the nitroglycerin patch should not be regarded in any way as a therapy of a free flap venous thrombosis but only as an useful device, an option to be taken only when the sur…

Venous Congestionmedicine.medical_specialtybusiness.industryVascular Pedicle Thrombosimedicine.medical_treatmentSettore MED/19 - Chirurgia PlasticaFree flapMicrosurgical ComplicationsAnastomosismedicine.diseaseSurgeryVenous thrombosisVenous congestionAnesthesiaSeromamedicineVenous anastomosisbusinessFree Flap FailureReduction (orthopedic surgery)Transdermal
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Enzymatically modified nonoxidized low-density lipoprotein induces interleukin-8 in human endothelial cells: role of free fatty acids.

2002

Background— Treatment of low-density lipoprotein (LDL) with a protease and cholesterolesterase transforms the lipoprotein to an entity that resembles lipoprotein particles in atherosclerotic lesions, which have a high content of free cholesterol, reflecting extensive de-esterification in the intima. Because de-esterification would occur beneath the endothelium, we examined the effects of enzymatically modified LDL (E-LDL) on cultured endothelial cells. Methods and Results— Incubation of endothelial cells with E-LDL provoked selective accumulation of interleukin (IL)-8 mRNA and production of the cytokine. Chemical analyses and depletion experiments indicated that the effect was caused by th…

Very low-density lipoproteinLow-density lipoprotein receptor-related protein 8EndotheliumNuclease Protection AssaysBiologychemistry.chemical_compoundPhysiology (medical)medicineHumansTrypsinInterleukin 8RNA MessengerCells CulturedIntermediate-density lipoproteinFatty AcidsInterleukin-8InterleukinBiological TransportSterol EsteraseMolecular biologyLipoproteins LDLmedicine.anatomical_structureBiochemistrychemistryGene Expression RegulationLow-density lipoproteinlipids (amino acids peptides and proteins)Cholesterol EstersEndothelium VascularCardiology and Cardiovascular MedicineOxidation-ReductionLipoproteinCirculation
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Feedback vibration control of a base-isolated building with delayed measurements using h<inf>∞</inf> techniques

2010

In this paper we address the problem of vibration reduction of buildings with delayed measurements, where the delays are time-varying and bounded. We focus on a convex optimization approach to the problem of state-feedback H ∞ control design. An appropriate Lyapunov-Krasovskii functional and some free weighting matrices are used to establish some delay-range-dependent sufficient conditions for the design of desired controllers in terms of linear matrix inequalities (LMIs). The controller, which guarantees asymptotic stability and an H ∞ performance, simultaneously, for the closed-loop system of the structure, is then developed. The performance of the controller is evaluated through the simu…

VibrationReduction (complexity)Exponential stabilityControl theoryBounded functionConvex optimizationVibration controlWeightingMathematicsProceedings of the 2010 American Control Conference
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Identifying critical incidents in naturalistic driving data: experiences from a promoting real life observation for gaining understanding of road use…

2013

The methodology of naturalistic driving observation aspires to observe the driver and his environment while driving in natural driving settings. It is of great importance in research on road safety as this method of observing road users eliminates the disadvantages of traditional methods like simulator studies or interviews. However, it produces vast such amounts of data and challenges data reduction and data analysis. Therefore automatic methods for filtering critical incidents based on thresholds for numerical data are often applied to select the data to be analysed. This study reports a small-scale field trial in Valencia, Spain, which was conducted within the promoting real life observa…

Video recordingEngineeringbusiness.industryMechanical EngineeringContrast (statistics)TransportationComputer securitycomputer.software_genreData scienceData qualityField trialScale (social sciences)Naturalistic drivingbusinessLawcomputerGeneral Environmental ScienceData reductionRoad userIET Intelligent Transport Systems
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Solvent-Enhanced Diastereo- and Regioselectivity in the PdII-Catalyzed Synthesis of Six- and Eight-Membered Heterocycles viacis-Aminopalladation

2009

The Pd(II)-catalyzed intramolecular oxidative cyclization of tosyl-protected cis- and trans-N-allyl-2-aminocyclohexanecarboxamides was examined, and efficient syntheses of cyclohexane-fused pyrimidin-4-ones and 1,5-diazocin-6-ones were developed. In the course of the research, a marked solvent effect was observed on both the regio- and diastereoselectivity. Additionally, a novel Pd(II)-mediated domino oxidation, oxidative amination reaction was discovered. Our experimental and theoretical findings suggest that the reactions proceed via a cis-aminopalladation mechanism.

Vinyl CompoundsCyclohexanecarboxylic AcidsStereochemistrychemistry.chemical_elementPyrimidinonesCatalysisCatalysisCyclohexanesAminationAminationCyclohexylaminesOxidative cyclizationMolecular StructureOrganic ChemistryRegioselectivityStereoisomerismGeneral ChemistryAzocinesAllyl CompoundsSolventchemistryCyclizationIntramolecular forceSolvent effectsOxidation-ReductionPalladiumPalladiumChemistry - A European Journal
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Challenging Dogma: Thresholds for Genotoxic Carcinogens? The Case of Vinyl Acetate

2002

Although many questions remain unanswered, the general principle of the sequence of events leading to cancer after exposure to genotoxic carcinogens has become increasingly clear. This helps to understand the parameters that influence the shape of the dose-effect curve for carcinogenesis, including metabolic activation and inactivation of carcinogens, DNA repair, cell cycle control, apoptosis, and control by the immune system. A linear dose-response relationship with no observable threshold seems to be a conservative but adequate description for the carcinogenic activity of many genotoxic carcinogens, such as aflatoxin B1, the tobacco-specific nitrosoketone NNK, and probably N,N-diethylnit…

Vinyl CompoundsDNA RepairCarcinogenicity TestsDNA repairDNA damagePH reductionToxicologymedicine.disease_causeRisk Assessmentchemistry.chemical_compoundAcetic acidmedicineVinyl acetateAnimalsHumansCarcinogenPharmacologyDose-Response Relationship DrugAcetaldehydeDNAchemistryBiochemistryCarcinogensCarcinogenesisDNA DamageMutagensAnnual Review of Pharmacology and Toxicology
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Supplementation with cactus pear (Opuntia ficus-indica) fruit decreases oxidative stress in healthy humans: a comparative study with vitamin C.

2004

Background: Cactus pear (Opuntia ficus-indica) fruit contains vitamin C and characteristic betalain pigments, the radical-scavenging properties and antioxidant activities of which have been shown in vitro. Objective: We investigated the effects of short-term supplementation with cactus pear fruit compared with vitamin C alone on total-body oxidative status in healthy humans. Design: In a randomized, crossover, double-treatment study, 18 healthy volunteers received either 250 g fresh fruit pulp or 75 mg vitamin C twice daily for 2 wk, with a 6-wk washout period between the treatments. Before (baseline) and after each treatment, 8-epiprostaglandin F2α (8-epi-PGF2α) and malondialdehyde in plas…

VitaminAdultMaleAntioxidantmedicine.medical_treatmentMedicine (miscellaneous)Ascorbic AcidBiologymedicine.disease_causechemistry.chemical_compoundSettore BIO/10 - BiochimicamedicineHumansFood scienceopuntia ficus indica. oxidative stress in vivoPEARNutrition and DieteticsCross-Over StudiesVitamin CVitamin EOpuntiaMalondialdehydeAscorbic acidOxidative StressBiochemistrychemistryFruitFemaleOxidation-ReductionOxidative stressBiomarkersThe American journal of clinical nutrition
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Contribution of vitamin A to the oxidation resistance of human low density lipoproteins.

1995

This study investigated the antioxidant contribution of vitamin A in protecting human low density lipoprotein (LDL) against copper-stimulated oxidation. The presence of small amounts of retinol (0.033 ± 0.012 nmol/mol LDL) and retinyl palmitate (0.036 ± 0.021 nmol/mol LDL) was routinely ascertained in the LDL. A single oral supplementation with 20,000 IU vitamin A caused a two- to three-fold increase of retinol and retinyl palmitate in the LDL isolated 8 h after the supplementation. In comparison to autologous-control LDL, vitamin A-enriched LDL were more resistant to oxidation, as expressed both by a clear delay in the onset of lipid peroxidation and by a reduction of the rate of conjugate…

VitaminAdultMaleRetinyl EstersAntioxidantFree RadicalsArteriosclerosismedicine.medical_treatmentRetinyl esterIn Vitro Techniquesmedicine.disease_causeBiochemistryAntioxidantsLDLLipid peroxidationchemistry.chemical_compoundFree radicalIn vivoPhysiology (medical)Retinyl palmitatemedicineHumansVitamin ARetinolRetinolMiddle AgedLipoproteins LDLKineticsOxidative StresschemistryBiochemistryAtherosclerosiLow-density lipoproteinlipids (amino acids peptides and proteins)FemaleLipid PeroxidationAntioxidantDiterpenesOxidation-ReductionOxidative stressCopperFree radical biologymedicine
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