954 resultados para Upper Paleozoic


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Task-oriented repetitive movements can improve motor recovery in patients with neurological or orthopaedic lesions. The application of robotics can serve to assist, enhance, evaluate, and document neurological and orthopaedic rehabilitation. ARMin is a new robot for arm therapy applicable to the training of activities of daily living in clinics. ARMin has a semiexoskeletal structure with six degrees of freedom, and is equipped with position and force sensors. The mechanical structure, the actuators and the sensors of the robot are optimized for patient-cooperative control strategies based on impedance and admittance architectures. This paper describes the mechanical structure, the control system, the sensors and actuators, safety aspects and results of a first pilot study with hemiplegic and spinal cord injured subjects.

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Task-oriented repetitive movements can improve muscle strength and movement co-ordination in patients with impairments due to neurological lesions. The application of robotics and automation technology can serve to assist, enhance, evaluate and document the rehabilitation of movements. The paper provides an overview of existing devices that can support movement therapy of the upper extremities in subjects with neurological pathologies. The devices are critically compared with respect to technical function, clinical applicability, and, if they exist, clinical outcomes.

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The Penninic nappes in the Swiss Alps formed during continental collision between the Adriatic and European plates in Cenozoic times. Although intensely studied, the finite geometry of the basement-bearing Penninic nappes in western Switzerland has remained a matter of debate for decades (e.g., “Siviez-Mischabel dilemma”) and the paleogeographic origin of various nappes has been disputed. Here, we present new structural data for the central part of the Penninic Bernard nappe complex, which contains pre-Permian basement and Permo-Mesozoic metasedimentary units. Our lithological and structural observations indicate that the discrepancy between the different structural models proposed for the Bernard nappe complex can be explained by a lateral discontinuity. In the west, the presence of a Permian graben caused complex isoclinal folding, whereas in the east, the absence of such a graben resulted mainly in imbricate thrusting. The overall geometry of the Bernard nappe complex is the result of three main deformation phases: (1) detachment of Mesozoic cover sediments along Triassic evaporites (Evolène phase) during the early stages of collision, (2) Eocene top-to-the-N(NW) nappe stacking (Anniviers phase), and (3) subsequent backfolding and backshearing (Mischabel phase). The southward localized backshearing is key to understand the structural position and paleogeographic origin of units, such as the Frilihorn and Cimes Blanches “nappes” and the Antrona ophiolites. Based on these observations, we present a new tectonic model for the entire Penninic region of western Switzerland and discuss this model in terms of continental collision zone processes.

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BACKGROUND Although well-established for suspected lower limb deep venous thrombosis, an algorithm combining a clinical decision score, d-dimer testing, and ultrasonography has not been evaluated for suspected upper extremity deep venous thrombosis (UEDVT). OBJECTIVE To assess the safety and feasibility of a new diagnostic algorithm in patients with clinically suspected UEDVT. DESIGN Diagnostic management study. (ClinicalTrials.gov: NCT01324037) SETTING: 16 hospitals in Europe and the United States. PATIENTS 406 inpatients and outpatients with suspected UEDVT. MEASUREMENTS The algorithm consisted of the sequential application of a clinical decision score, d-dimer testing, and ultrasonography. Patients were first categorized as likely or unlikely to have UEDVT; in those with an unlikely score and normal d-dimer levels, UEDVT was excluded. All other patients had (repeated) compression ultrasonography. The primary outcome was the 3-month incidence of symptomatic UEDVT and pulmonary embolism in patients with a normal diagnostic work-up. RESULTS The algorithm was feasible and completed in 390 of the 406 patients (96%). In 87 patients (21%), an unlikely score combined with normal d-dimer levels excluded UEDVT. Superficial venous thrombosis and UEDVT were diagnosed in 54 (13%) and 103 (25%) patients, respectively. All 249 patients with a normal diagnostic work-up, including those with protocol violations (n = 16), were followed for 3 months. One patient developed UEDVT during follow-up, for an overall failure rate of 0.4% (95% CI, 0.0% to 2.2%). LIMITATIONS This study was not powered to show the safety of the substrategies. d-Dimer testing was done locally. CONCLUSION The combination of a clinical decision score, d-dimer testing, and ultrasonography can safely and effectively exclude UEDVT. If confirmed by other studies, this algorithm has potential as a standard approach to suspected UEDVT. PRIMARY FUNDING SOURCE None.

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The polysaccharide capsule and pneumolysin toxin are major virulence factors of the human bacterial pathogen Streptococcus pneumoniae. Colonization of the nasopharynx is asymptomatic but invasion of the lungs can result in invasive pneumonia. Here we show that the capsule suppresses the release of the pro-inflammatory cytokines CXCL8 (IL-8) and IL-6 from the human pharyngeal epithelial cell line Detroit 562. Release of both cytokines was much less from human bronchial epithelial cells (iHBEC) but levels were also affected by capsule. Pneumolysin stimulates CXCL8 release from both cell lines. Suppression of CXCL8 homologue (CXCL2/MIP-2) release by the capsule was also observed in vivo during intranasal colonization of mice but was only discernable in the absence of pneumolysin. When pneumococci were administered intranasally to mice in a model of long term, stable nasopharyngeal carriage, encapsulated S. pneumoniae remained in the nasopharynx whereas the nonencapsulated pneumococci disseminated into the lungs. Pneumococcal capsule plays a role not only in protection from phagocytosis but also in modulation of the pro-inflammatory immune response in the respiratory tract.

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In the Mt. Olympos region of northeastern Greece, continental margin strata and basement rocks were subducted and metamorphosed under blueschist facies conditions, and thrust over carbonate platform strata during Alpine orogenesis. Subsequent exposure of the subducted basement rocks by normal faulting has allowed an integrated study of the timing of metamorphism, its relationship to deformation, and the thermal history of the subducted terrane. Alpine low-grade metamorphic assemblages occur at four structural levels. Three thrust sheets composed of Paleozoic granitic basement and Mesozoic metasedimentary cover were thrust over Mesozoic carbonate rocks and Eocene flysch; thrusting and metamorphism occurred first in the highest thrust sheets and progressed downward as units were imbricated from NE to SW. 40Ar/39Ar spectra from hornblende, white mica, and biotite samples indicate that the upper two units preserve evidence of four distinct thermal events: (1) 293–302 Ma crystallization of granites, with cooling from >550°C to <325°C by 284 Ma; (2) 98–100 Ma greenschist to blueschist-greenschist transition facies metamorphism (T∼350–500°C) and imbrication of continental thrust sheets; (3) 53–61 Ma blueschist facies metamorphism and deformation of the basement and continental margin units at T<350–400°C; (4) 36–40 Ma thrusting of blueschists over the carbonate platform, and metamorphism at T∼200–350°C. Only the Eocene and younger events affected the lower two structural packages. A fifth event, indicated by diffusive loss profiles in microcline spectra, reflects the beginning of uplift and cooling to T<100–150°C at 16–23 Ma, associated with normal faulting which continued until Quaternary time. Incomplete resetting of mica ages in all units constrains the temperature of metamorphism during continental subduction to T≤350°C, the closure temperature for Ar in muscovite. The diffusive loss profiles in micas and K-feldspars enable us to “see through” the younger events to older events in the high-T parts of the release spectra. Micas grown during earlier metamorphic events lost relatively small amounts of Ar during subsequent high pressure-low temperature metamorphism. Release spectra from phengites grown during Eocene metamorphism and deformation record the ages of the Ar-loss events. Alpine deformation in northern Greece occurred over a long time span (∼90 Ma), and involved subduction and episodic imbrication of continental basement before, during, and after the collision of the Apulian and Eurasian plates. Syn-subduction uplift and cooling probably combined with intermittently higher cooling rates during extensional events to preserve the blueschist facies mineral assemblages as they were exhumed from depths of >20 km. Extension in the Olympos region was synchronous with extension in the Mesohellenic trough and the Aegean back-arc, and concurrent with westward-progressing shortening in the external Hellenides.

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Genetic predispositions for guttural pouch tympany, recurrent laryngeal neuropathy and recurrent airway obstruction (RAO) are well documented. There is also evidence that exercise-induced pulmonary haemorrhage and infectious diseases of the respiratory tract in horses have a genetic component. The clinical expression of equine respiratory diseases with a genetic basis results from complex interactions between the environment and the genetic make-up of each individual horse. The genetic effects are likely to be due to variations in several genes, i.e. they are polygenic. It is therefore unlikely that single gene tests will be diagnostically useful in these disorders. Genetic profiling panels, combining several genetic factors with an assessment of environmental risk factors, may have greater value, but much work is still needed to uncover diagnostically useful genetic markers or even causative variants for equine respiratory diseases. Nonetheless, chromosomal regions associated with guttural pouch tympany, recurrent laryngeal neuropathy and RAO have been identified. The association of RAO with other hypersensitivities and with resistance to intestinal parasites requires further study. This review aims to provide an overview of the available data and current thoughts on the genetics of equine airway diseases.

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U–Pb zircon analyses from three meta-igneous and two metasedimentary rocks from the Siviez-Mischabel nappe in the western Swiss Alps are presented, and are used to derive an evolutionary history spanning from Paleoarchean crustal growth to Permian magmatism. The oldest components are preserved in zircons from metasedimentary albitic schists. The oldest zircon core in these schists is 3.4 Ga old. Detrital zircons reveal episodes of crustal growth in the Neoarchean (2.7–2.5 Ga), Paleoproterozoic (2.2–1.9 Ma) and Neoproterozoic (800–550 Ma, Pan-African event). The maximum age of deposition for the metasedimentary rocks is given by the youngest detrital zircons within both metasedimentary samples dated at ~490 Ma (Cambrian-Ordovician boundary). This is in the age range of two granitoid samples dated at 505 ± 4 and 482 ± 7 Ma, and indicates sedimentation and magmatism in an extensional setting preceding an Ordovician orogeny. The third felsic meta-igneous rock gives a Permian age of intrusion, and is part of a long-lasting Variscan to post-Variscan magmatic activity. The zircons record only minor disturbance of the U–Pb system during the Alpine orogeny.

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The basis of personalized medicine in oncology is the prediction of an individual's risk of relapse and death from disease. The presence of tumor budding (TB) at the tumor-host interface of gastrointestinal cancers has been recognized as a hallmark of unfavorable disease biology. TB is defined as the presence of dedifferentiated cells or small clusters of up to five cells at the tumor invasive front and can be observed in aggressive carcinomas of the esophagus, stomach, pancreas, ampulla, colon, and rectum. Presence of TB reproducibly correlates with advanced tumor stage, frequent lymphovascular invasion, nodal, and distant metastasis. The UICC has officially recognized TB as additional independent prognostic factor in cancers of the colon and rectum. Recent studies have also characterized TB as a promising prognostic indicator for clinical management of esophageal squamous cell carcinoma, adenocarcinoma of the gastro-esophageal junction, and gastric adenocarcinoma. However, several important issues have to be addressed for application in daily diagnostic practice: (1) validation of prognostic scoring systems for TB in large, multi-center studies, (2) consensus on the optimal assessment method, and (3) inter-observer reproducibility. This review provides a comprehensive analysis of TB in cancers of the upper gastrointestinal tract including critical appraisal of perspectives for further study.

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PURPOSE To determine the variability of apparent diffusion coefficient (ADC) values in various anatomic regions in the upper abdomen measured with magnetic resonance (MR) systems from different vendors and with different field strengths. MATERIALS AND METHODS Ten healthy men (mean age, 36.6 years ± 7.7 [standard deviation]) gave written informed consent to participate in this prospective ethics committee-approved study. Diffusion-weighted (DW) MR imaging was performed in each subject with 1.5- and 3.0-T MR systems from each of three vendors at two institutions. Two readers independently measured ADC values in seven upper abdominal regions (left and right liver lobe, gallbladder, pancreas, spleen, and renal cortex and medulla). ADC values were tested for interobserver differences, as well as for differences related to field strength and vendor, with repeated-measures analysis of variance; coefficients of variation (CVs) and variance components were calculated. RESULTS Interreader agreement was excellent (intraclass coefficient, 0.876). ADC values were (77.5-88.8) ×10(-5) mm(2)/sec in the spleen and (250.6-278.5) ×10(-5) mm(2)/sec in the gallbladder. There were no significant differences between ADC values measured at 1.5 T and those measured at 3.0 T in any anatomic region (P >.10 for all). In two of seven regions at 1.5 T (left and right liver lobes, P < .023) and in four of seven regions at 3.0 T (left liver lobe, pancreas, and renal cortex and medulla, P < .008), intervendor differences were significant. CVs ranged from 7.0% to 27.1% depending on the anatomic location. CONCLUSION Despite significant intervendor differences in ADC values of various anatomic regions of the upper abdomen, ADC values of the gallbladder, pancreas, spleen, and kidney may be comparable between MR systems from different vendors and between different field strengths.