Search results for "fixation"

A geometrical framework for f –statistics

2020

AbstractA detailed derivation of the f–statistics formalism is made from a geometrical framework. It is shown that the f–statistics appear when a genetic distance matrix is constrained to describe a four population phylogenetic tree. The choice of genetic metric is crucial and plays an outstanding role as regards the tree–like–ness criterion. The case of lack of treeness is interpreted in the formalism as presence of population admixture. In this respect, four formulas are given to estimate the admixture proportions. One of them is the so–called f4–ratio estimate and we show that a second one is related to a known result developed in terms of the fixation index FST. An illustrative numerica…

Learning Curve in Surgical Treatment of Odontoid Fixation for a Series of Type II C2 Fractures

2019

The craniovertebral junction (CVJ) is a complex anatomical area upon which most of the motion of the upper cervical spine depends [1]. Because of its unique range of motion, the CVJ is subject to several types of traumatic injury; it has been shown that odontoid fractures are the most common ones in the general population and are the most common isolated spinal fractures [2]. Accounting for up to 18% of all cervical fractures, odontoid fractures are the most common ones in elderly patients [3], in whom they account for up to 60% of spinal cord injuries [4].

Subjective and Objective Outcomes of Ankle Joint Arthrodesis with Either Ilizarov or Internal Fixation

2021

After arthroplasty, arthrodesis of the ankle joint is the most common method to treat advanced ankle osteoarthritis. The goal of the study was to assess the subjective and objective outcomes in 2 different types of fixation for ankle joint arthrodesis. We retrospectively assessed 47 patients who had undergone ankle joint arthrodesis with fixation either via an Ilizarov apparatus (group 1) (n = 21) or cannulated screws (group 2) (n = 26). The outcomes were measured by: (1) the quantity of analgesics administered, (2) the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, (3) general patient satisfaction, (4) the patients' decision to undergo the same procedure given an…

L'inoculation des légumineuses en France : un exemple de coopération entre l'INRA de Dijon et les fabricants d'inoculant

2013

EAMERSslides (31 diapositives); L'inoculation des légumineuses en France : un exemple de coopération entre l'INRA de Dijon et les fabricants d'inoculant

Does the movement pattern of non-visual eye movements during episodic vs semantic memory tasks correspond to Lévy Flights?: Poster

2021

Does the movement pattern of non-visual eye movements during episodic vs semantic memory tasks correspond to Lévy Flights?: Oral presentation

2021

Simple Configuration Effects on Eye Movements in Horizontal Scanning Tasks

2015

When reading text, observers alternate periods of stable gaze (fixations) and shifts of gaze (saccades). An important debate in the literature concerns the processes that drive the control of these eye movements. Past studies using strings of letters rather than meaningful text ('z-reading') suggest that eye movement control during reading is, to a large extent, controlled by low-level image properties. These studies, however, have failed to take into account perceptual grouping processes that could drive these low-level effects. We here study the role of various grouping factors in horizontal scanning eye movements, and compare these to reading meaningful text. The results show that sequen…

The determination of the initial straight length in root canals of mandibular premolars--an in vitro study.

2009

Abstract The aim of the present roentgenographic in vitro study was to determine the initial straight length from the cemento-enamel junction (CEJ) to the appearance of a root canal curvature in human mandibular premolars. A total number of 282 mandibular premolars were examined. Exclusion criteria comprised root caries, extensive restorations and endodontically treated teeth. The teeth were fixed and digitally radiographed by means of a specially developed fixation device with standardized and reproducible distances with the parallel technique (Heliodent MD; Merlin 2.1). The distances from the CEJ to the first curvature (> 5°) (distance I), from the first curvature to a second curvature (d…

Concentration of chromium and nickel in serum of patients with orthopedic implant: An analysis

2021

Introduction: Surgical corrections of fracture using fixation devices made from various alloys (stainless steel, cobalt-chromium alloys, and titanium) carry a risk of these alloys leaching into circulation, potentially causing undesired health effects. Hence, monitoring the levels of metal ions in the serum of postoperative patients with metal implants is mandated. Materials and Methods: Blood samples from seventy patients with orthopedic metal implants was collected after a minimum postoperative period of 1 year. The samples were subjected to triple acid digestion and serum levels of chromium and nickel were analyzed using inductively coupled plasma-mass spectrometry. Results: The concentr…

Reversible inhibition of CO2fixation by ribulose 1,5-bisphosphate carboxylase/oxygenase through the synergic effect of arsenite and a monothiol

2013

The activity of the photosynthetic carbon-fixing enzyme, ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco), is partially inhibited by arsenite in the millimolar concentration range. However, micromolar arsenite can fully inhibit Rubisco in the presence of a potentiating monothiol such as cysteine, cysteamine, 2-mercaptoethanol or N-acetylcysteine, but not glutathione. Arsenite reacts specifically with the vicinal Cys172-Cys192 from the large subunit of Rubisco and with the monothiol to establish a ternary complex, which is suggested to be a trithioarsenical. The stability of the complex is strongly dependent on the nature of the monothiol. Enzyme activity is fully recovered through …