Search results for "vision."

showing 10 items of 4900 documents

Effects of movement direction upon kinematic characteristics of vertical arm pointing movements in man

1998

Vertical arm pointing movements in two directions (upwards and downwards), imposing two different loads (unload and 0.5 kg) and speeds (normal and fast) have been studied in six subjects. Movements were recorded using an optoelectronic system. Data analysis concentrated upon finger-tip kinematics. Significant effects of movement direction were recorded upon velocity profiles. The acceleration time, computed relative to total movement time, was greater for downward movements than for upward movements. In contrast however, no effects of load or speed were observed. Movement time was not affected by movement direction or load, for both speeds tested. These results suggest different planning pr…

AdultMaleGravity (chemistry)Time FactorsWeight LiftingDecelerationMovementmedia_common.quotation_subjectAccelerationAcceleration timeKinematicsFunctional LateralityFingersHumansContrast (vision)Gravitational forcemedia_commonMovement (music)General NeuroscienceGeodesyBiomechanical PhenomenaTorqueAerospace MedicineArmGeologyGravitationNeuroscience Letters
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Human walking along a curved path. I. Body trajectory, segment orientation and the effect of vision.

2003

Task-related characteristics of gait and segment orientation during natural locomotion along a curved path have been described in order to gain insight into the neural organization of walking. The locomotor task implied continuous deviation from straight-ahead, thereby requiring continuous adjustment of body movement to produce and assist turn-related torques. Performance was compared to straight-ahead locomotion. Subjects easily reproduced both trajectories with eyes open (EO). The actual-to-required trajectory difference increased blindfolded (BF), more so during turning. Stride length was unchanged for the outer but decreased for the inner leg. The feet anticipated subsequent body rotati…

AdultMaleHeading (navigation)FootGeneral NeuroscienceBody movementKinematicsWalkingMiddle AgedRotationTrunkBiomechanical PhenomenaGait (human)Control theoryOrientation (geometry)Head MovementsOrientationTrajectoryHumansGaitAlgorithmsPsychomotor PerformanceVision OcularMathematicsThe European journal of neuroscience
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European Society of Cardiology

2022

Abstract Aims This report from the European Society of Cardiology (ESC) Atlas Project updates and expands upon the widely cited 2019 report in presenting cardiovascular disease (CVD) statistics for the 57 ESC member countries. Methods and results Statistics pertaining to 2019, or the latest available year, are presented. Data sources include the World Health Organization, the Institute for Health Metrics and Evaluation, the World Bank, and novel ESC sponsored data on human and capital infrastructure and cardiovascular healthcare delivery. New material in this report includes sociodemographic and environmental determinants of CVD, rheumatic heart disease, out-of-hospital cardiac arrest, left…

AdultMaleHealth infrastructureStatisticsCardiologyCardiovascular diseaseCardiovascular SystemEuropean Society of CardiologyCardiovascular DiseasesRisk FactorsIncomeHumansFemaleService provisionMortalityMorbidityCardiology and Cardiovascular MedicineEuropean Heart Journal
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Influence of stimulus color on the control of reaching-grasping movements.

2001

This kinematic study aimed to determine whether color is a stimulus property involved in the control of reaching-grasping movements. Subjects reached and grasped a target-object, located either on the right or on the left of the subject's midline. A distractor, placed along the subject's midline, could be randomly presented. The colors, i.e., both chromaticity (red and green stimuli were presented) and lightness, of the target and distractor were varied in experiment 1. Only stimulus lightness and only stimulus chromaticity were varied in experiments 2 and 3, respectively. In experiment 4 subjects matched with their thumb and index finger the size of the target-stimuli presented in experime…

AdultMaleHuman kinematicsProperty (programming)MovementKinematicsStimulus (physiology)Neuropsychological TestsTarget colorOpticsOrientationmedicineReaction TimeHumansComputer visionChromaticity and lightnessChromaticityHand Strengthbusiness.industryGeneral NeuroscienceGRASPMotor controlReaching-graspingBody movementIndex fingerBiomechanical Phenomenamedicine.anatomical_structurePattern Recognition VisualSpace PerceptionArmFemaleArtificial intelligencebusinessPsychologyInterferenceReaching-grasping · Human kinematics · Target color · Chromaticity and lightness · InterferenceColor PerceptionPhotic StimulationPsychomotor PerformanceExperimental brain research
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Maintenance of marginal bone support and soft tissue esthetics at immediately provisionalized OsseoSpeed implants placed into extraction sites: 2-yea…

2012

Background Placement of implants into extraction sockets targets the maintenance of peri-implant hard and soft tissue structures and the support of a natural and esthetic contour. The main advantages of immediate implant insertion in comparison with delayed implant placement protocols are as follows: a reduced treatment time, less number of sessions, and, thus, the less invasive procedure. This study examines the clinical performance (survival rate, marginal bone levels and Pink Esthetic Score [PES]) of OsseoSpeed™ implants placed into extraction sockets with immediate provisionalization in the anterior maxilla after a follow-up of at least 12 months. Methods Twenty patients received a tota…

AdultMaleImmediate Dental Implant LoadingFacial boneEstheticsmedicine.medical_treatmentAlveolar Bone LossDentistryProsthesisDental Implants Single-ToothAlveolar ProcessMedicineHumansProspective StudiesTooth SocketSurvival rateAgedbusiness.industryAlveolar processClinical performanceSoft tissueMiddle AgedImmediate provisionalizationmedicine.anatomical_structureTreatment OutcomeDental Prosthesis DesignFemaleImplantOral SurgerybusinessClinical oral implants research
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Knowledge about glaucoma in the unselected population: a German survey.

2002

Purpose To determine the general population's knowledge about glaucoma. Materials and methods A representative survey of the German population was conducted in which 2,742 men and women were interviewed face to face. The sample was matched with the German population for age, sex, education, income, and other factors. Questions were asked concerning the nature, occurrence, possible risk factors, and course of glaucoma. Results Fifty-one percent of the population had an active knowledge of the term "glaucoma" and 75% had a passive knowledge of the term. Of those interviewees with a passive knowledge, glaucoma was thought to be associated with raised intraocular pressure (IOP) by 28% and loss …

AdultMaleIntraocular pressurePediatricsmedicine.medical_specialtyHealth Knowledge Attitudes Practicegenetic structuresAdolescentPopulationMEDLINEGlaucomaDiseaseGermanBlurred visionRisk FactorsSurveys and QuestionnairesmedicineHumanseducationIntraocular PressureAgedAged 80 and overeducation.field_of_studybusiness.industryMiddle Agedmedicine.diseaseeye diseaseslanguage.human_languageOphthalmologylanguageUnselected populationFemalesense organsmedicine.symptombusinessGlaucoma Open-AngleJournal of glaucoma
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Posterior chamber phakic intraocular lenses to correct high myopia: A comparative study between Staar and Adatomed models

2001

ABSTRACT PURPOSE: To determine the feasibility of using posterior chamber phakic intraocular lenses (PIOLs) to treat high myopia, comparing two different models, Staar and Adatomed. METHODS: Twenty-four eyes from 12 patients were studied prospectively. A phakic Staar IOL was implanted in one eye of each patient, and the other eye received a phakic Adatomed IOL. Patients with uveitis or ocular trauma prior to ocular surgery, diabetic retinopathy, or capsular pseudoexfoliation were excluded. The mean preoperative spherical equivalent refraction was -16.00 ± 5.05 D for the Staar group and -15.39 ± 2.83 D for the Adatomed group. Average follow-up was 32.4 months (range, 19 to 46 mo) for the Ada…

AdultMaleIntraocular pressureRefractive errormedicine.medical_specialtyAnterior subcapsular cataractVisual acuitygenetic structuresEye diseasemedicine.medical_treatmentLens Capsule CrystallineVisual AcuityIntraocular lensRefraction OcularPhakic intraocular lensCataractVision disorderPostoperative ComplicationsForeign-Body MigrationLens Implantation IntraocularLens CrystallineMyopiaHumansMedicineIntraocular PressureLenses Intraocularbusiness.industrymedicine.diseaseeye diseasesSurgeryOphthalmologyFeasibility StudiesFemaleSurgerysense organsmedicine.symptombusinessFollow-Up Studies
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Long-term observation of endocrine ophthalmopathy and retrospective appraisal of therapeutic measures.

1990

The course of endocrine ophthalmopathy was investigated on the basis of clinical and biochemical parameters and in relation to different therapeutic strategies. A retrospective appraisal was made of 297 patients (44 +/- 14 yr, 249 women) with inclusion of anamnestic and clinical data as well as the results of computer tomography. At the beginning of therapy, 253 patients were hyperthyroid, 36 were euthyroid and eight were hypothyroid. The HLA typing carried out in 89 patients showed the phenotypes B8 and DR3 in 32% and 42% of the cases, respectively. Raised microsomal antibodies were present in 56% of the patients and there were raised thyroglobulin antibodies in 19%. Sixty-three % of the p…

AdultMaleIntraocular pressuremedicine.medical_specialtyTime FactorsAdolescentEye DiseasesEndocrinology Diabetes and MetabolismEye diseasemedicine.medical_treatmentVision DisordersCyclosporinsEndocrine System DiseasesEyeAutoimmune DiseasesEndocrinologyImmunopathologyInternal medicinemedicineExophthalmosHumansEuthyroidEndocrine ophthalmopathyGlucocorticoidsIntraocular PressureVision OcularAgedRetrospective Studiesbusiness.industryMusclesRetrospective cohort studyMiddle Agedmedicine.diseaseSurgeryPrednisoneThyroglobulinFemalebusinessComplicationTomography X-Ray ComputedJournal of endocrinological investigation
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Intrastromal corneal ring segment implantation in paracentral keratoconus with coincident topographic and coma axis.

2012

To evaluate the efficacy, predictability, and safety of implantation of Ferrara-type intrastromal corneal ring segments (ICRS) for refractive correction of paracentral keratoconus.Fernández-Vega Ophthalmological Institute, Oviedo, Spain.Cohort study.Snellen uncorrected (UDVA) and corrected (CDVA) distance visual acuities and residual refractive errors were recorded before and 6 months after ICRS implantation for keratoconus. The tunnels for ICRS implantation were created with a femtosecond laser. The power vector and the Alpins method were used to analyze postoperative refractive outcomes.The study evaluated 56 eyes of 49 patients. The mean UDVA was 0.17 ± 0.14 (SD) preoperatively and 0.41 …

AdultMaleKeratoconusmedicine.medical_specialtygenetic structuresmedicine.medical_treatmentCorneal StromaVision DisordersVisual AcuityComa (optics)Power vectorKeratoconusRefraction OcularCohort StudiesProsthesis ImplantationYoung AdultOphthalmologymedicineHumansPolymethyl MethacrylateProspective StudiesAlpins methodAgedIntrastromal corneal ring segmentbusiness.industryCorneal TopographyProstheses and ImplantsMiddle Agedmedicine.diseaseeye diseasesSensory SystemsSurgeryOphthalmologySurgeryFemalesense organsLaser TherapyCorneal ringbusinessJournal of cataract and refractive surgery
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Planning an action.

1997

The motor control of a sequence of two motor acts forming an action was studied in the present experiment. The two analysed motor acts were reaching-grasping an object (first target) and placing it on a second target of the same shape and size (experiment 1). The aim was to determine whether extrinsic properties of the second target (i.e. target distance) could selectively influence the kinematics of reaching and grasping. Distance, position and size of both targets were randomly varied across the experimental session. The kinematics of the initial phase of the first motor act, that is, velocity of reaching and hand shaping of grasping, were influenced by distance of the second target. No k…

AdultMaleKinematicsComputer scienceMovementPoison controlKinematicsStimulus (physiology)Visual controlFingersMental ProcessesHumansComputer visionMotor actCommunicationLift (data mining)business.industryGeneral NeuroscienceGRASPReaching-graspingMotor controlBody movementWristHandPlacingThumbArmFemaleArtificial intelligencebusinessPsychomotor PerformanceExperimental brain research
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