998 resultados para Almost Complex Manifold


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Within the ORAMED project a coordinated measurement program for occupationally exposed medical staff was performed in different hospitals in Europe. The main objectives of ORAMED were to obtain a set of standardized data on doses for staff in interventional cardiology and radiology and to optimize staff protection. Doses were measured with thermoluminescent dosemeters on the ring finger and wrist of both hands, on legs and at the level of the eyes of the main operator performing interventional procedures. In this paper an overview of the doses per procedure measured during 646 interventional cardiology procedures is given for cardiac angiographies and angioplasties (CA/PTCA), radiofrequency ablations (RFA) and pacemaker and defibrillator implantations (PM/ICD). 31% of the monitored procedures were associated with no collective protective equipment, whereas 44% involved a ceiling screen and a table curtain. Although associated with the smallest air kerma - area product (KAP), PM/ICD procedures led to the highest doses. As expected, KAP and doses values exhibited a very large variability. The left side of the operator, most frequently the closest to the X-ray scattering region, was more exposed than his right side. An analysis of the effect of parameters influencing the doses, namely collective protective equipment, X-ray tube configuration and catheter access route, was performed on the doses normalized to KAP. Ceiling screen and table curtain were observed to reduce normalized doses by atmost a factor 4, much smaller than theoretical attenuation factors typical for such protections, i.e. from 10 to 100. This observation was understood as their inappropriate use by the operators and their non-optimized design. Configurations with tube above the patient led to higher normalized doses to the operator than tube below, but the effect of using a biplane X-ray suite was more complex to analyze. For CA/PTCA procedures, the upper part of the operator's body received higher normalized doses for radial than for femoral catheter access, by atmost a factor 5. This could be seen for cases with no collective protection. The eyes were observed to receive the maximum fraction of the annual dose limit almost as frequently as legs and hands, and clearly the most frequently, if the former 150 mSv and new 20 mSv recommended limits for the lens of the eye are considered, respectively.

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Four distinct rock units have been recognized near El Aguacate, in the Janico-Juncalito-La Vega area of the Duarte complex (Dominican Republic): (1) serpentinites crosscut by numerous diabasic dikes, (2) basalts interbedded with Late Jurassic ribbon cherts, (3) picrites and ankaramites relatively enriched in incompatible trace elements, and (4) amphibolites and gneissic amphibolites chemically similar to Oceanic Plateau Basalts. Similar Ar-Ar ages of late magmatic amphibole from a picrite, and hornblende from an amphibolite (86.1 +/- 1.3 Ma and 86.7 +/- 1.6 Ma, respectively), suggest that the Duarte picrites are contemporaneous with the Deep Sea Drilling Program Leg 15 and Ocean Drilling Program Leg 126 basalts drilled from the Caribbean oceanic plateau. These basalts are associated with sediments containing Late Cretaceous faunas. Sr, Nd, and Pb data show that enriched picrites and amphibolites are isotopically similar to mafic lavas from previously described Caribbean plateau and Galapagos hotspot basalts. Major element, trace element, and lead isotopic features of Late Jurassic basalts and diabases are consistent with those of normal oceanic crust basalt. However, these basalts differ from typical N-MORB because they have lower epsilon Nd ratios that plot within the range of Ocean Island Basalts. These rocks appear to represent remnants of the Caribbean Jurassic oceanic crust formed from an oceanic ridge possibly close to a hotspot. Later, they were tectonically juxtaposed with Late Cretaceous slices of the Caribbean-Colombian plateau.

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Background Morbidly obese patients are at high risk to develop gallstones, and rapid weight loss after bariatric surgery further enhances this risk. The concept of prophylactic cholecystectomy during gastric bypass has been challenged recently because the risk may be lower than reported earlier and because cholecystectomy during laparoscopic gastric bypass may be more difficult and risky. <p>Methods A review of prospectively collected data on 772 patients who underwent laparoscopic primary gastric bypass between January 2000 and August 2007 was performed. The charts of patients operated before 2004 were retrospectively reviewed regarding preoperative echography and histopathological findings.</p> <p>Results Fifty-eight (7.5%) patients had had previous cholecystectomy. In the remaining patients, echography showed gallstones or sludge in 81 (11.3%). Cholecystectomy was performed at the time of gastric bypass in 665 patients (91.7%). Gallstones were found intraoperatively in 25 patients (3.9%), for a total prevalence of gallstones of 21.2%. The age of patients with gallstones was higher than that of gallstone-free patients (43.5 vs 38.7 years, p < 0.0001). Of the removed specimens, 81.8% showed abnormal histologic findings, mainly chronic cholecystitis and cholesterolosis. Cholecystectomy was associated with no procedure-related complication, prolonged duration of surgery by a mean of 19 min (4-45), and had no effect on the duration of hospital stay. Cholecystectomy was deemed too risky in 59 patients (8.3%) who were prescribed a 6-month course of ursodeoxycolic acid.</p> <p>Conclusion Concomitant cholecystectomy can be performed safely in most patients during laparoscopic gastric bypass and does not prolong hospital stay. As such, it is an acceptable form of prophylaxis against stones forming during rapid weight loss. Whether it is superior to chemical prophylaxis remains to be demonstrated in a large prospective randomized study.</p>

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BACKGROUND: Accurate catalogs of structural variants (SVs) in mammalian genomes are necessary to elucidate the potential mechanisms that drive SV formation and to assess their functional impact. Next generation sequencing methods for SV detection are an advance on array-based methods, but are almost exclusively limited to four basic types: deletions, insertions, inversions and copy number gains. RESULTS: By visual inspection of 100 Mbp of genome to which next generation sequence data from 17 inbred mouse strains had been aligned, we identify and interpret 21 paired-end mapping patterns, which we validate by PCR. These paired-end mapping patterns reveal a greater diversity and complexity in SVs than previously recognized. In addition, Sanger-based sequence analysis of 4,176 breakpoints at 261 SV sites reveal additional complexity at approximately a quarter of structural variants analyzed. We find micro-deletions and micro-insertions at SV breakpoints, ranging from 1 to 107 bp, and SNPs that extend breakpoint micro-homology and may catalyze SV formation. CONCLUSIONS: An integrative approach using experimental analyses to train computational SV calling is essential for the accurate resolution of the architecture of SVs. We find considerable complexity in SV formation; about a quarter of SVs in the mouse are composed of a complex mixture of deletion, insertion, inversion and copy number gain. Computational methods can be adapted to identify most paired-end mapping patterns.

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The first and second internal transcribed spacer regions (ITS1 and ITS2) of the ribosomal DNA of Biomphalaria tenagophila complex (B. tenagophila, B. occidentalis, and B. t. guaibensis) were sequenced and compared. The alignment lengths of these regions were about 655 bp and 481 bp, respectively. Phylogenetic relationships among the Biomphalaria species were inferred by Maximum Parsimony and Neighbor-joining methods. The phylogenetic trees produced, in most of the cases, were in accordance with morphological systematics and other molecular data previously obtained by polymerase chain reaction and restriction fragment length polymorphism analysis. The present results provide support for the proposal that B. tenagophila represents a complex comprising B. tenagophila, B. occidentalis and B. t. guaibensis.

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Li contents [Li] and isotopic composition (delta Li-7) of mafic minerals (mainly amphibole and clinopyroxene) from the alkaline to peralkaline Ilimaussaq plutonic complex, South Greenland, track the behavior of Li and its isotopes during magmatic differentiation and final cooling of an alkaline igneous system. [Li] in amphibole increase from < 10 ppm in Caamphiboles of the least differentiated unit to >3000 ppm in Na-amphiboles of the highly evolved units. In contrast, [Li] in clinopyroxene are comparatively low (<85 ppm) and do not vary systematically with differentiation. The distribution of Li between amphibole and pyroxene is controlled by the major element composition of the minerals (Ca-rich and Na-rich, respectively) and changes in oxygen fugacity (due to Li incorporation via coupled substitution with ferric iron) during magmatic differentiation. delta(7) Li values of all minerals span a wide range from + 17 to - 8 parts per thousand, with the different intrusive units of the complex having distinct Li isotopic systematics. Amphiboles, which dominate the Li budget of whole-rocks from the inner part of the complex, have constant delta Li-7 of + 1.8 +/- 2.2 parts per thousand (2 sigma, n = 15). This value reflects a homogeneous melt reservoir and is consistent with their mantle derivation, in agreement with published O and Nd isotopic data. Clinopyroxenes of these samples are consistently lighter, with Delta Li-7(amph-cpx). as large as 8 parts per thousand and are thus not in Li isotope equilibrium. These low values probably reflect late-stage diffusion of Li into clinopyroxene during final cooling of the rocks, thus enriching the clinopyroxene in 6 Li. At the margin of the complex delta(7) Li in the syenites increases systematically, from +2 to high values of + 14 parts per thousand. This, coupled with the observed Li isotope systematics of the granitic country rocks, reflects post-magmatic open-system processes occurring during final cooling of the intrusion. Although the shape and magnitude of the Li isotope and elemental profiles through syenite and country rock are suggestive of diffusion-driven isotope fractionation, they cannot be modeled by one-dimensional diffusive transport and point to circulation of a fluid having a high 67 Li value (possibly seawater) along the chilled contact. In all, this study demonstrates that Li isotopes can be used to identify complex fluid- and diffusion-governed processes taking place during the final cooling of such rocks. (c) 2007 Elsevier B.V All rights reserved.

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Mycobacterium kansasii is the most common cause of pulmonary nontuberculous mycobacteria infection and classical identification of this pathogen needs a time consuming phenotypic tests. Polymerase chain reaction-restriction fragment lenght polymorphism analysis (PRA) of the gene enconding for the 65kDa heat shock (hsp65) protein offers an easy, rapid, and inexpensive procedure to identify and subtype M. kansasii isolates. In the present study, we performed a retrospective analysis of patients who had mycobacteria identified on the basis of phenotypic tests by means of a review of database at Mycobacteria Laboratory of the Instituto Adolfo Lutz in the period 1995-1998. A total of 9381 clinical isolates were analyzed of which 7777 (82.9%) were identified as M. tuberculosis complex and 1604 (17.1%) as nontuberculous mycobacteria. Of the 296 M. kansasii isolates, 189 (63.8%) isolates obtained from 119 patients were viable and were analyzed by PRA-hsp65. Hundred eight two (98.9%) were classified as M. kansasii type I. Two isolates were classified as type II and III and five isolates were characterized as other Mycobacterium species. Clinical isolates of M. kansasii in the state of São Paulo was almost exclusively subtype I regardless of HIV status.

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Mycobacterium tuberculosis complex (MTBC) members are causative agents of human and animal tuberculosis. Differentiation of MTBC members is required for appropriate treatment of individual patients and for epidemiological purposes. Strains from six MTBC species - M. tuberculosis, M. bovis subsp. bovis, M. bovis BCG, M. africanum, M. pinnipedii, and "M. canetti" - were studied using gyrB-restriction fragment length polymorphism (gyrB-RFLP) analysis. A table was elaborated, based on observed restriction patterns and published gyrB sequences. To evaluate applicability of gyrB-RFLP at Instituto Adolfo Lutz, São Paulo, Mycobacterial Reference Laboratory, 311 MTBC clinical isolates, previously identified using traditional methods as M. tuberculosis (306), M. bovis (3), and M. bovis BCG (2), were analyzed by gyrB-RFLP. All isolates were correctly identified by the molecular method, but no distinction between M. bovis and M. bovis BCG was obtained. Differentiation of M. tuberculosis and M. bovis is of utmost importance, because they require different treatment schedules. In conclusion, gyrB-RFLP is accurate and easy-to-perform, with potential to reduce time needed for conventional differentiation methods. However, application for epidemiological studies remains limited, because it cannot differentiate M. tuberculosis from M. africanum subtype II, and "M. canetti", M. africanum subtype I from M. pinnipedii, and. M. bovis from M. bovis BCG.

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Anopheles (Nyssorhynchus) marajoara is a proven primary vector of malaria parasites in Northeast Brazil, and An. deaneorum is a suspected vector in Western Brazil. Both are members of the morphologically similar Albitarsis Complex, which also includes An. albitarsis and an undescribed species, An. albitarsis "B". These four species were recognized and can be identified using random amplified polymorphic DNA (RAPD) markers, but various other methodologies also point to multiple species under the name An. albitarsis. We describe here a technique for identification of these species employing polymerase chain reaction (PCR) primers based on ribosomal DNA internal transcribed spacer 2 (rDNA ITS2) sequence. Since this method is based on known sequence it is simpler than the sometimes problematical RAPD-PCR. Primers were tested on samples previously identified using RAPD markers with complete correlation.

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In order to evaluate the taeniosis-cysticercosis complex in a population of a peasants' settlement, located at Teodoro Sampaio, state of São Paulo, Brazil (longitude 52° 36'12 ", latitude 22° 17'12 ") a series of laboratory markers were determined. After signing an informed consent, participants answered a standardized questionnaire. To determine anti-Taenia solium cysticercus antibodies, the samples were tested by enzyme linked immunoabsorbent assay using 18-and 14-kDa antigen proteins from vesicular fluid of Taenia crassiceps (VF-Tcra). The reactive and inconclusive ELISA samples were tested by immunoblotting. Total IgE levels were determined by chemmiluminescence's assay and hemogram by flow cytometer flux counter. A total of 84 individuals, 5.9% presented anti-T. solium cysticercus antibodies in ELISA and 3.6% were strongly reactive in the 18/14 kDa immunoblotting confirmatory test. All of the individuals with positive antibodies showed elevated Total IgE levels. We conclude that the frequency of anti-T. solium cysticercus antibodies in this population is higher than other regions considered endemic in São Paulo. Thus, it is important to carry out surveys in Peasants' settlement areas with the objective of establishing public health measures for prevention and control of infectious diseases such as taeniosis-cysticercosis.

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The unstable rock slope above the village of Flåm shows signs of active and postglacial gravitational deformation over an area of 11 km2. We performed detailed structural field mapping, annual differential Global Navigation Satellite System (GNSS) surveys, and generated a detailed topographic model based on airborne and terrestrial laser scanning. Kinematic analyses of the structural data indicates that deformation is complex and varies over the slope. Both sliding and toppling are locally feasible. Using differential GNSS, 18 points were measured annually over a period of up to 6 years. Two of these points show an average yearly movement of around 10 mm/year. They are located at the frontal cliff on almost completely detached blocks. Large fractures indicate deep-seated gravitational deformation of volumes up to 80 million m3, but the movement rates in these areas are below 2 mm/year. Based upon these combined observations, we interpret that small collapses of blocks along the frontal cliff will be more frequent. Larger collapses of free-standing blocks along the cliff with volumes >100,000 m3, thus large enough to reach the fjord, cannot be ruled out. A large collapse involving more than 10 million m3, however, is of very low likelihood at present.

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A hydrophobic cuticle is deposited at the outermost extracellular matrix of the epidermis in primary tissues of terrestrial plants. Besides forming a protective shield against the environment, the cuticle is potentially involved in several developmental processes during plant growth. A high degree of variation in cuticle composition and structure exists between different plant species and tissues. Lots of progress has been made recently in understanding the different steps of biosynthesis, transport, and deposition of cuticular components. However, the molecular mechanisms that underlie cuticular function remain largely elusive.

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Aspects related to hatching, life time, number of blood meals to molt, mortality, feeding time and postfeed defecation delay for each instar of Meccus phyllosomus, M. mazzottii, and M. bassolsae, life-cycle were evaluated and compared in two cohorts of each of those three species, fed on hens or rabbits. No significant (p > 0.05) differences were recorded among cohorts fed on hens respect to cohorts fed on rabbits in M. phyllosomus and M. mazzottii and the average time of hatching was 21.5 days for cohorts fed on hens and 22.5 for cohorts fed on rabbits. Average egg-to-adult development times were no significant (p > 0.05) different between both cohorts of M. phyllosomus and M. mazzotti, independent of the blood meal source. The average span in days for each instar fed on hens was not significantly different to the average span for each instar fed on rabbits, when comparisons were made by species. The number of blood meals at each nymphal instar varied from 1 to 6 in both cohorts of each species. The mortality rates were higher on older nymphs, in both cohorts of M. phyllosomus and M. bassolsae, whereas they were higher on first instar nymphs on M. mazzottii. Mean feeding time was no significant (p > 0.05) different in triatomines fed on hens or fed on rabbits, when each species were compared separately. A similar number of nymphs of each cohort, completed the cycle. Defecation delay was no significant (p > 0.05) different when cohorts fed on hens and fed on rabbits were compared by species. Most of the studied parameters showed no significant (p > 0.05) differences among those cohorts fed on hens and for fed on rabbits, which could mean a high degree of association of those species with birds as much as mammals, under wild conditions, increasing their capacity to colonize human dwellings.

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Lutzomyia longipalpis is the main vector of Leishmania infantum chagasi, the causative agent of American visceral leishmaniasis (AVL). Although there is strong evidence that Lu. longipalpis is a species complex, not all data concerning populations from Brazil support this hypothesis. The issue is still somewhat controversial for this large part of Lu. longipalpis distribution range even though that it is the Latin American region contributing to most of the cases of AVL. In this mini-review we consider in detail the current data for the Brazilian populations and conclude that Lu. longipalpis is a complex of incipient vector species with a complexity similar to Anopheles gambiae s.s. in Africa.