Search results for " geometry"
showing 10 items of 2294 documents
MR imaging of the heart in patients after myocardial infarction: effect of increasing intersection gap on measurements of left ventricular volume, ej…
1999
International audience; Abstract: PURPOSE: To determine the extent to which the number of planes imaged at magnetic resonance (MR) imaging could be reduced without modifying the volume and thickness of the left ventricle. MATERIALS AND METHODS: Sixty-one patients were examined after a myocardial infarction. The whole left ventricle was imaged by using 5-mm contiguous breath-hold cine MR short-axis sections with no gap (SA(ng)) (two-dimensional fast low-angle shot sequence, 9/4.8 [repetition time msec/echo time msec]). The effect of omitting in two (short-axis sections with 5-mm gap [SA(5mm)]) or two sections in three(short-axis sections with 10-mm gap [SA(10mm)]) was studied. RESULTS: In th…
Greater maintenance of bone mineral content in male than female athletes and in sprinting and jumping than endurance athletes: a longitudinal study o…
2020
Abstract Summary We investigated longitudinal changes in tibia bone strength in master power (jumping and sprinting) and endurance (distance) athletes of both sexes. Bone mass but not cross-sectional moment of inertia was better maintained in power than endurance athletes over time, particularly in men and independent of changes in performance. Objective Assessment of effects of sex and athletic discipline (lower limb power events, e.g. sprint running and jumping versus endurance running events) on longitudinal changes in bone strength in masters athletes. Methods We examined tibia and fibula bone properties at distal (4% distal-proximal tibia length) and proximal (66% length) sites using p…
Do bone geometric properties of the proximal femoral diaphysis reflect loading history, muscle properties, or body dimensions?
2019
Abstract Objectives: The aim of this study was to investigate activity‐induced effects from bone geometric properties of the proximal femur in athletic vs nonathletic healthy females by statistically controlling for variation in body size, lower limb isometric, and dynamic muscle strength, and cross‐sectional area of Musculus gluteus maximus. Methods: The material consists of hip and proximal thigh magnetic resonance images of Finnish female athletes (N = 91) engaged in either high jump, triple jump, soccer, squash, powerlifting, endurance running or swimming, and a group of physically active nonathletic women (N = 20). Cross‐sectional bone geometric properties were calculated for the lesse…
Left ventricular hypertrophy in chronic kidney disease: A diagnostic criteria comparison.
2020
Background and aims: CKD patients have a high prevalence of LVH and this leads to an increase of cardiovascular risk. The aim of this study was to assess the prevalence of left ventricular hypertrophy (LVH) and left ventricular geometry in a group of 293 hypertensive patients with stage 2–5 chronic kidney disease (CKD), compared with 289 essential hypertensive patients with normal renal function. Methods and results: All patients underwent echocardiographic examination. Patients on stage 1 CKD, dialysis treatment, or with cardiovascular diseases were excluded. LVH was observed in 62.8% of patients with CKD and in 51.9% of essential hypertensive patients (P < 0.0001). We found increasingl…
Subgrouping factors influencing migraine intensity in women: A semi-automatic methodology based on machine learning and information geometry
2019
[EN] Background Migraine is a heterogeneous condition with multiple clinical manifestations. Machine learning algorithms permit the identification of population groups, providing analytical advantages over other modeling techniques. Objective The aim of this study was to analyze critical features that permit the differentiation of subgroups of patients with migraine according to the intensity and frequency of attacks by using machine learning algorithms. Methods Sixty-seven women with migraine participated. Clinical features of migraine, related disability (Migraine Disability Assessment Scale), anxiety/depressive levels (Hospital Anxiety and Depression Scale), anxiety state/trait levels (S…
Validity of the Colposcopic Criteria Inner Border Sign, Ridge Sign, and Rag Sign for Detection of High-Grade Cervical Intraepithelial Neoplasia
2013
OBJECTIVE: To evaluate the association of three patho-gnomonic criteria, inner border, ridge sign, and rag sign with high-grade cervical intraepithelial neoplasia (CIN) using video exoscopy. METHODS: Retrospective evaluation of video recordings of 335 patients, referred for diagnostic colposcopy, who underwent cervical biopsies, and, if indicated loop excisions, was performed. The most severe histologic diagnosis was recorded. Sensitivity, specificity, positive, negative predictive value, and likelihood ratios for highgrade CIN were calculated. RESULTS: In 285 patients (85%), a single colposcopy directed biopsy was taken; 50 patients (15%) underwent two biopsies. One hundred sixty-two patie…
Darstellung von Hyperebenen in verallgemeinerten affinen Räumen durch Moduln
1994
The starting point of this article is a generalized concept of affine space which includes all affine spaces over unitary modules. Our main result is a representation theorem for hyperplanes of affine spaces: Every hyperplane which satisfies a weak richness condition is induced by a module. 1
Affine Kettengeometrien �ber Jordanalgebren
1996
It is shown that an affine chain geometry over a Jordan algebra can be constructed in a nearly classical manner. Conversely, such chain geometries are characterized as systems of rational normal curves having a group of automorphisms with certain properties.
The coordinatization of affine planes by rings
1996
With every unitary free module of rank 2 there is naturally associated a generalized affine plane (e.g. the lines are just the cosets of all nonzero 1-generated submodules). Here we solve the converse problem by coordinatizing a given generalized affine plane which satisfies certain versions of Desargues' postulate.
On the algebraic representation of projectively embeddable affine geometries
1995
The main result of this article is an application of [1] and [2] which yields that an at least 2-dimensional affine geometry is module-induced if and only if it is projectively embeddable into an Arguesian projective lattice geometry.