999 resultados para Diagram of an algebra


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OBJECTIVES: We report a new salvage technique for treating venous aneurysms (VAs) complicating vascular access arteriovenous fistula (AVF) using externally reinforced venous aneurysmorrhaphy. DESIGN: A retrospective study over a 20-month period from a single centre. PATIENTS: Patients presenting to the vascular surgery department, Bordeaux University Hospital for revision of a vascular access AVF were included. METHODS: Reinforced venous aneurysmorrhaphy consisted in removal of redundant vessel wall followed by reinforcement using an external prosthetic graft. Patency, diameter and flow were assessed by duplex ultrasound at 1, 6 and 12 months after salvage. RESULTS: Thirty-eight eligible patients were identified. Five were excluded because VA was associated with central vein stenosis; the remaining 33 underwent salvage. Indications were rapidly expanding or painful VA in seven cases; VA with frequent bleeding or damaged overlying skin in eight; VA in close relation to a stenosis in two; and VA associated with high-flow rate in 16. Cannulation was attempted after 30 days. Mean follow-up time was 12 S.D. 5 months (range: 4-22). Two repaired AVFs failed. Primary 1-year patency was 93%. No aneurysm or infection occurred. Reduction of high flow was successful in 12 of 16 patients. The remaining four required re-operation. CONCLUSIONS: Reinforced venous aneurysmorrhaphy is effective in controlling venous dilation and achieving patency. Reduction of high-flow rates was not always achieved. Further study is needed to evaluate long-term efficacy of this treatment.

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We present the application of terrestrial laser scanning (TLS) for the monitoring and characterization of an active landslide area in Val Canaria (Ticino, Southern Swiss Alps). At catchment scale, the study area is affected by a large Deep Seated Gravitational Slope Deformation (DSGSD) area presenting, in the lower boundary, several retrogressive landslides active since the 1990s. Due to its frequent landslide events this area was periodically monitored by TLS since 2006. Periodic acquisitions provided new information on 3D displacements at the bottom of slope and the detection of centimetre to decimetre level scale changes (e.g. rockfall and pre-failure deformations). In October 2009, a major slope collapse occured at the bottom of the most unstable area. Based on the comparison between TLS data before and after the collapse, we carried out a detailed failure mechanism analysis and volume calculation.

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BACKGROUND:   Complications associated with intrathecal pumps may be linked to the surgical procedure, the implanted device, or the medication itself.¦CASE REPORTS:   Three patients treated chronically with intrathecal clonidine presented with clonidine overdose due to inadvertent extravasation during the refilling procedure. All patients experienced loss of consciousness and severe systemic hypertension that required aggressive parenteral treatment.¦DISCUSSION:   Clonidine is an alpha-2 agonist with a nearly 100% bioavailability after oral or rectal administration. With high plasma concentration secondary to massive systemic overdose, the specificity for the alpha-2 receptor is lost and an alpha-1 agonist activity predominates and causes marked hypertension. Management of clonidine overdose consists of supportive therapy guided by signs and symptoms.¦CONCLUSION:   Inadvertent injection into the subcutaneous pocket rather than the reservoir is rare but very dangerous as the drug cannot be retrieved and massive doses are involved. Signs and symptoms of systemic overdose with drugs commonly used in implanted drugs delivery system should be well known to ensure early diagnosis and treatment.

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Plagued for nearly a century by the perennial flooding of Indian Creek, the City begins construction on a massive channelization project designed to confine the creek to its banks. Funded largely through a grant from the recently established Public Works Administration (PWA), the Indian Creek Channel, upon its completion two years later, would become the largest PWA undertaking in the State of Iowa. Though it did not completely end flooding in Council Bluffs, construction of the Indian Creek Channel did substantially reduce both the number and severity of the city's subsequent floods. It also profoundly impacted the residential and commercial development of Council Bluffs, as well as the city's sanitary conditions. The effects of the Indian Creek channelization, both practical and historical, are still realized today. In 2009, plans for a City road and bridge construction project at the intersection of North Broadway Street and Kanesville Boulevard proposed to replace a 221-foot-long segment of the Indian Creek Channel with a concrete box culvert. In compliance with the National Historic Preservation Act, a cultural resources study was conducted at the proposed construction site, the findings of which concluded that the historic character of the Indian Creek Channel would be compromised by the impending construction. As a means of mitigating these damages, an agreement was reached among the City, the Iowa State Historic Preservation Office, and the Federal Highway Administration that resulted in detailed research and documentation of the historical significance of the Indian Creek Channel. The findings of that study are summarized in this publication.

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OBJECTIVE: To emphasize that complex regional pain syndrome (CRPS), a disabling disorder with the implication of aberrant inflammation, vasomotor dysfunction, and maladaptive neuroplasticity, might be treated with a high dose of intravenous immunoglobulin infusions (IVIG). METHODS: We describe a patient who presented with CRPS in the acute phase of the disease. RESULTS: The CRPS developed secondary to sciatic compression in a young patient and was treated within 10 days by high-dose IVIG (2 g/kg). It resolved completely within days after infusions. DISCUSSION: This observational study emphasizes that high-dose IVIG may be a treatment option in the acute phase of CRPS.

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Species of Scolytidae and Platypodidae were evaluated in a plantation using a clone of Eucalyptus grandis x Eucalyptus urophylla in the State of Minas Gerais, Brazil. Wood disks with galleries were taken from 15 eucalyptus trees between 0.5 and 1.5 m height. After collection, all trees attacked were burned. Woodborers obtained from these disks were identified as Premnobius cavipennis, Premnobius ambitiosus, Dryocoetoides cristatus (Coleoptera: Scolytidae) and Euplatypus parallelus (Coleoptera: Platypodidae). This is the first report of D. cristatus, a Brazilian native species, damaging eucalyptus, which shows its adaptation to this plant.

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Preterm birth may represent a traumatic situation for both parents and a stressful situation for the infant, potentially leading to difficulties in mother-infant relationships. This study aimed to investigate the impact of an early intervention on maternal posttraumatic stress symptoms, and on the quality of mother-infant interactions, in a sample of very preterm infants and their mothers. Half of the very preterm infants involved in the study (n=26) were randomly assigned to a 3-step early intervention program (at 33 and 42 weeks after conception and at 4 months' corrected age). Both groups of preterm infants (with and without intervention) were compared to a group of full-term infants. The impact of the intervention on maternal posttraumatic stress symptoms was assessed 42 weeks after conception and when the infants were 4 and 12 months of age. The impact of the intervention on the quality of mother-infant interactions was assessed when the infants were 4 months old. Results showed a lowering of mothers' posttraumatic stress symptoms between 42 weeks and 12 months in the group of preterm infants who received the intervention. Moreover, an enhancement in maternal sensitivity and infant cooperation during interactions was found at 4 months in the group with intervention. In the case of a preterm birth, an early intervention aimed at enhancing the quality of the mother-infant relationship can help to alleviate maternal post-traumatic stress symptoms and may have a positive impact on the quality of mother-infant interactions.

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We report on two familial cases from a non-consanguineous marriage, presenting multiple intestinal and choanal atresia. Massive hydramnios and dilatation of the bowel were observed at 29 weeks of gestation during routine ultrasound scan of a healthy mother. The fetal karyotype was normal and cystic fibrosis screening was negative. Regular scans were performed throughout the pregnancy. The child was born at 34 weeks gestation. Choanal atresia was diagnosed at birth and abdominal investigations showed multiple atresia interesting both the small bowel and the colon. Further interventions were necessary because of recurrent obstructions. During the following pregnancy, a dilatation of the fetal intestinal tract was detected by ultrasonography at 27 weeks of gestation. Pregnancy was interrupted. Post-mortem examination of the fetus confirmed the stenosis of long segments of the small intestine associated with areas of colonic atresia. In both cases, histology and distribution were consistent with those reported in hereditary multiple intestinal atresia (HMIA). An association between multiple intestinal and choanal atresia has never been reported. We suggest it could correspond to a new autosomal recessive entity for which cytogenetic investigations and high-resolution array CGH revealed no visible anomalies.

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X-linked hypohidrotic ectodermal dysplasia (XLHED; OMIM 305100) is a genetic disorder characterized by absence or deficient function of hair, teeth and sweat glands. Affected children may experience life-threatening high fever resulting from reduced ability to sweat. Mice with the Tabby phenotype share many symptoms with human XLHED patients because both phenotypes are caused by mutations of the syntenic ectodysplasin A gene (Eda) on the X chromosome. Two main splice variants of Eda, encoding EDA1 and EDA2, engage the tumor necrosis factor (TNF) family receptors EDAR and XEDAR, respectively. The EDA1 protein, acting through EDAR, is essential for proper formation of skin appendages; the functions of EDA2 and XEDAR are not known. EDA1 must be proteolytically processed to a soluble form to be active. Here, we show that treatment of pregnant Tabby mice with a recombinant form of EDA1, engineered to cross the placental barrier, permanently rescues the Tabby phenotype in the offspring. Notably, sweat glands can also be induced by EDA1 after birth. This is the first example of a developmental genetic defect that can be permanently corrected by short-term treatment with a recombinant protein.

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Pseudomonas fluorescens CHA0, an effective biological control agent of soilborne plant diseases, is naturally non-mucoid. We have isolated a highly mucoid Tn5 insertion mutant of strain CHA0. The mucoid phenotype was found to be due to the overproduction of exopolysaccharide (EPS), as a result of a mutation in the mucA gene. The wild-type mucA gene was cloned by a two-step, Tn5-dependent cloning procedure previously described and the deduced amino acid sequence showed 71% identity with MucA of P. aeruginosa, a negative regulator of the alternative sigma factor AlgU (=s22, sE). As in P. aeruginosa, mucA is preceded by the algU gene encoding s22 (91% identity at the amino acid sequence level). A mucA in-frame deletion mutant of CHA0 overproduced EPS and formed mucoid colonies, whereas an algU in-frame deletion mutant showed a non-mucoid phenotype. Pyoluteorin, an antibiotic produced by P. fluorescens, was found to be entrapped in EPS of a mucoid mutant. In natural soil, mucoidy negatively affected survival of the bacteria, suggesting that under these conditions the potential to produce abundant EPS does not confer a selective advantage on the bacteria.

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PURPOSE: To review, retrospectively, the possible causes of sub- or intertrochanteric fractures after screw fixation of intracapsular fractures of the proximal femur. METHODS: Eighty-four patients with an intracapsular fracture of proximal femur were operated between 1995 and 1998 by using three cannulated 6.25 mm screws. The screws were inserted in a triangular configuration, one screw in the upper part of the femoral neck and two screws in the inferior part. Between 1999 and 2001, we use two screws proximally and one screw distally. RESULTS: In the first series, two patients died within one week after operation. Sixty-four fractures healed without problems. Four patients developed an atrophic non-union; avascular necrosis of the femoral head was found in 11 patients. Three patients (3.6%) suffered a sub- and/or intertrochanteric fracture after a mean postoperative time of 30 days, in one case without obvious trauma. In all three cases surgical revision was necessary. Between 1999 and 2001 we did not observe any fracture after screwing. CONCLUSION: Two screws in the inferior part of the femoral neck create a stress riser in the subtrochanteric region, potentially inducing a fracture in the weakened bone. For internal fixation for proximal intracapsular femoral fracture only one screw must be inserted in the inferior part of neck.

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This paper describes the result of a research about diverse areas of the information technology world applied to cartography. Its final result is a complete and custom geographic information web system, designed and implemented to manage archaeological information of the city of Tarragona. The goal of the platform is to show on a web-focused application geographical and alphanumerical data and to provide concrete queries to explorate this. Various tools, between others, have been used: the PostgreSQL database management system in conjunction with its geographical extension PostGIS, the geographic server GeoServer, the GeoWebCache tile caching, the maps viewer and maps and satellite imagery from Google Maps, locations imagery from Google Street View, and other open source libraries. The technology has been chosen from an investigation of the requirements of the project, and has taken great part of its development. Except from the Google Maps tools which are not open source but are free, all design has been implemented with open source and free tools.

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Résumé : L'arc volcanique du sud de l'Amérique Centrale se situe sur la marge SW de la Plaque Caraïbe, au-dessus des plaques subduites de Cocos et Nazca. Il s'agit de l'un des arcs intra-océaniques les plus étudiés au monde, qui est généralement considéré comme s'étant développé à la fin du Crétacé le long d'un plateau océanique (le Plateau Caraïbe ou CLIP) et se trouvant actuellement dans un régime de subduction érosive. Au cours des dernières décennies, des efforts particuliers ont été faits pour comprendre les processus liés à la subduction sur la base d'études géophysiques et géochimiques. Au sud du Costa Rica et à l'ouest du Panama, des complexes d'accrétions et structures à la base de l'arc volcanique ont été exposés grâce à la subduction de rides asismiques et de failles transformantes. Des affleurements, situés jusqu'à seulement 15 km de la fosse, offrent une possibilité unique de mieux comprendre quelques uns des processus ayant lieu le long de la zone de subduction. Nous présentons de nouvelles contraintes sur l'origine de ces affleurements en alliant une étude de terrain poussée, de nouvelles données géochimiques, sédimentaires et paléontologiques, ainsi que des observations structurales effectuées en télédétection. Une nouvelle stratigraphie tectonique entre le Campanien et l'Éocène est définie pour la région d'avant-arc située entre la Péninsule d'Osa (Costa Rica) et la Péninsule d'Azuero (Panama). Nos résultats montrent que la partie externe de la marge est composée d'un arrangement complexe de roches ignées et de séquences sédimentaires de recouvrement qui comprennent principalement le socle de l'arc, des roches d'arc primitif, des fragments de monts sous-marins accrétés et des mélanges d'accrétion. Des preuves sont données pour le développement de l'arc volcanique du sud de l'Amérique Centrale sur un plateau océanique. Le début de la subduction le long de la marge SW de la Plaque Caraïbe a eu lieu au Campanien et a généré des roches d'arc primitif caractérisées par des affinités géochimiques particulières, globalement intermédiaires entre des affinités de plateau et d'arc insulaire. L'arc était mature au Maastrichtien et formait un isthme essentiellement continu entre l'Amérique du Nord et l'Amérique du Sud. Ceci a permis la migration de faunes terrestres entre les Amériques et pourrait avoir contribué à la crise fin Crétacé -Tertiaire en réduisant les courants océaniques subéquatoriaux entre le Pacifique et l'Atlantique. Plusieurs unités composées de fragments de monts sous-marins accrétés sont définies. La nature et l'arrangement structural de ces unités définissent de nouvelles contraintes sur les modes d'accrétion des monts sous-marins/îles océaniques et sur l'évolution de la marge depuis la formation de la zone de subduction. Entre la fin du Crétacé et l'Éocène moyen, la marge a enregistré plusieurs épisodes ponctuels d'accrétion de monts sous-marins alternant avec de la subduction érosive. A l'Éocène moyen, un événement tectonique régional pourrait avoir causé un fort couplage entre les plaques supérieure et inférieure, menant à des taux plus important d'accrétion de monts sous-marins. Durant cette période, la situation le long de la marge était très semblable à la situation actuelle et caractérisée par la présence de monts sous-marins subductants et l'absence d'accrétion de sédiments. L'enregistrement géologique montre qu'il n'est pas possible d'attribuer une nature érosive ou accrétionnaire à la marge dans le passé ou -par analogie- aujourd'hui, parce que (1) les processus d'accrétion et érosifs varient fortement spatialement et temporellement et (2) il est impossible d'évaluer la quantité exacte de matériel tectoniquement enlevé à la marge depuis le début de la subduction. Au sud du Costa Rica, certains fragments de monts sous-marins accrétés sont représentatifs d'une interaction entre une ride et un point chaud dans le Pacifique au Crétacé terminal/Paléocène. L'existence de ces fragments de monts sous-marins et la morphologie du fond de l'Océan Pacifique indiquent que la formation de la ride de Cocos-Nazca s'est formée au moins ~40 Ma avant l'âge proposé par les modèles tectoniques actuels. Au Panama, nous avons identifié une île océanique d'âge début Éocène qui a été accrétée à l'Éocène moyen. L'accrétion a eu lieu à très faible profondeur par détachement de l'île dans la fosse, et a mené à une exceptionnelle préservation des structures volcaniques. Des affleurement comprenant aussi bien des parties basses et hautes de l'édifice volcanique on été étudiées, depuis la phase sous-marine bouclier jusqu'à la phase subaérienne post-bouclier. La stratigraphie nous a permis de différencier les laves de la phase sous-marine de celles de la phase subaérienne. La composition des laves indique une diminution progressive de l'intensité de la fusion partielle de la source et une diminution de la température des laves produites durant les derniers stades de l'activité volcanique. Nous interprétons ces changements comme étant liés à l'éloignement progressif de l'île océanique de la zone de fusion ou point chaud. Abstract The southern Central American volcanic front lies on the SW edge of the Caribbean Plate, inboard of the subducting Cocos and Nazca Plates. It is one of the most studied intra-oceanic convergent margins around the world, which is generally interpreted to have developed in the late Cretaceous along an oceanic plateau (the Caribbean Large Igneous Province or CLIP) and to be currently undergoing a regime of subduction erosion. In the last decades a particular effort has been made to understand subduction-related processes on the basis of geophysical and geochemical studies. In southern Costa Rica and western Panama accretionary complexes and structures at the base of the volcanic front have been exposed in response to subduction of aseismic ridges and transforms. Onland exposures are located as close as to 15 km from the trench and provide a unique opportunity to better understand some of the processes occurring along the subduction zone. We provide new constraints on the origins of these exposures by integrating a comprehensive field work, new geochemical, sedimentary and paleontological data, as well as structural observations based on remote imaging. A new Campanian to Eocene tectonostratigraphy is defined for the forearc area located between the Osa Peninsula (Costa Rica) and the Azuero Peninsula (Panama). Our results show that the outer margin is composed of a complicated arrangement of igneous complexes and overlapping sedimentary sequences that essentially comprise an arc basement, primitive island-arc rocks, accreted seamount fragments and accretionary mélanges. Evidences are provided for the development of the southern Central American arc on the top an oceanic plateau. The subduction initiation along the SW edge of the Caribbean Plate occurred in the Campanian and led to formation of primitive island-arc rocks characterized by unusual geochemical affinities broadly intermediate between plateau and arc affinities. The arc was mature in the Maastrichtian and was forming a predominantly continuous landbridge between the North and South Americas. This allowed migration of terrestrial fauna between the Americas and may have contributed to the Cretaceous-Tertiary crisis by limiting trans-equatorial oceanic currents between the Pacific and the Atlantic. Several units composed of accreted seamount fragments are defined. The nature of the units and their structural arrangement provide new constraints on the modes of accretion of seamounts/oceanic islands and on the evolution of the margin since subduction initiation. Between the late Cretaceous and the middle Eocene, the margin recorded several local episodes of seamount accretion alternating with tectonic erosion. In the middle Eocene a regional tectonic event may have triggered strong coupling between the overriding and subducting plates, leading to higher rates of seamount accretion. During this period the situation along the margin was very similar to the present and characterized by subducting seamounts and absence of sediment accretion. The geological record shows that it is not possible to ascribe an overall erosive or accretionary nature to the margin in the past and, by analogy, today, because (1) accretionary and erosive processes exhibit significant lateral and temporal variations and (2) it is impossible to estimate the exact amount of material tectonically eroded from the margin since subduction initiation. In southern Costa Rica, accreted seamount fragments point toward a plume-ridge interaction in the Pacific in the late Cretaceous/Paleocene. This occurrence of accreted seamount fragments and morphology of the Pacific Ocean floor is indicative of the formation of the Cocos-Nazca spreading system at least ~40 Ma prior to the age proposed in current tectonic models. In Panama, we identified a remarkably-well preserved early Eocene oceanic island that accreted in the middle Eocene. The accretion probably occurred at very shallow depth by detachment of the island in the trench and led to an exceptional preservation of the volcanic structures. Exposures of both deep and superficial parts of the volcanic edifice have been studied, from the submarine-shield to subaerial-postshield stages. The stratigraphy allowed us to distinguish lavas produced during the submarine and subaerial stages. The lava compositions likely define a progressive diminution of source melting and a decrease in the temperature of erupted melts in the latest stages of volcanic activity. We interpret these changes to primarily reflect the progressive migration of the oceanic island out of the melting region or hotspot.