914 resultados para Free ports and zones


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OBJECTIVE: To study the neurocognitive profile and its relationship to prefrontal dysfunction in non-demented Parkinson's disease (PD) with deficient haptic perception. METHODS: Twelve right-handed patients with PD and 12 healthy control subjects underwent thorough neuropsychological testing including Rey complex figure, Rey auditory verbal and figural learning test, figural and verbal fluency, and Stroop test. Test scores reflecting significant differences between patients and healthy subjects were correlated with the individual expression coefficients of one principal component, obtained in a principal component analysis of an oxygen-15-labeled water PET study exploring somatosensory discrimination that differentiated between the two groups and involved prefrontal cortices. RESULTS: We found significantly decreased total scores for the verbal learning trials and verbal delayed free recall in PD patients compared with normal volunteers. Further analysis of these parameters using Spearman's ranking correlation showed a significantly negative correlation of deficient verbal recall with expression coefficients of the principal component whose image showed a subcortical-cortical network, including right dorsolateral-prefrontal cortex, in PD patients. CONCLUSION: PD patients with disrupted right dorsolateral prefrontal cortex function and associated diminished somatosensory discrimination are impaired also in verbal memory functions. A negative correlation between delayed verbal free recall and PET activation in a network including the prefrontal cortices suggests that verbal cues and accordingly declarative memory processes may be operative in PD during activities that demand sustained attention such as somatosensory discrimination. Verbal cues may be compensatory in nature and help to non-specifically enhance focused attention in the presence of a functionally disrupted prefrontal cortex.

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Commercially available LaBr3:5% Ce3+ scintillators show with photomultiplier tube readout about 2.7% energy resolution for the detection of 662 keV γ-rays. Here we will show that by co-doping LaBr3:Ce3+ with Sr2+ or Ca2+ the resolution is improved to 2.0%. Such an improvement is attributed to a strong reduction of the scintillation light losses that are due to radiationless recombination of free electrons and holes during the earliest stages (1–10 ps) inside the high free charge carrier density parts of the ionization track.

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The first part of this paper provides a comprehensive and self-contained account of the interrelationships between algebraic properties of varieties and properties of their free algebras and equational consequence relations. In particular, proofs are given of known equivalences between the amalgamation property and the Robinson property, the congruence extension property and the extension property, and the flat amalgamation property and the deductive interpolation property, as well as various dependencies between these properties. These relationships are then exploited in the second part of the paper in order to provide new proofs of amalgamation and deductive interpolation for the varieties of lattice-ordered abelian groups and MV-algebras, and to determine important subvarieties of residuated lattices where these properties hold or fail. In particular, a full description is given of all subvarieties of commutative GMV-algebras possessing the amalgamation property.

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BACKGROUND & AIMS Sporadic pancreatic neuroendocrine tumors (pNETs) are rare and genetically heterogeneous. Chromosome instability (CIN) has been detected in pNETs from patients with poor outcomes, but no specific genetic factors have been associated with CIN. Mutations in death domain-associated protein gene (DAXX) or ATR-X gene (ATRX) (which both encode proteins involved in chromatin remodeling) have been detected in 40% of pNETs, in association with activation of alternative lengthening of telomeres. We investigated whether loss of DAXX or ATRX, and consequent alternative lengthening of telomeres, are related to CIN in pNETs. We also assessed whether loss of DAXX or ATRX is associated with specific phenotypes of pNETs. METHODS We collected well-differentiated primary pNET samples from 142 patients at the University Hospital Zurich and from 101 patients at the University Hospital Bern (both located in Switzerland). Clinical follow-up data were obtained for 149 patients from general practitioners and tumor registries. The tumors were reclassified into 3 groups according to the 2010 World Health Organization classification. Samples were analyzed by immunohistochemistry and telomeric fluorescence in situ hybridization. We correlated loss of DAXX, or ATRX, expression, and activation of alternative lengthening of telomeres with data from comparative genomic hybridization array studies, as well as with clinical and pathological features of the tumors and relapse and survival data. RESULTS Loss of DAXX or ATRX protein and alternative lengthening of telomeres were associated with CIN in pNETs. Furthermore, loss of DAXX or ATRX correlated with tumor stage and metastasis, reduced time of relapse-free survival, and decreased time of tumor-associated survival. CONCLUSIONS Loss of DAXX or ATRX is associated with CIN in pNETs and shorter survival times of patients. These results support the hypothesis that DAXX- and ATRX-negative tumors are a more aggressive subtype of pNET, and could lead to identification of strategies to target CIN in pancreatic tumors.

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Samples obtained from different locations within the prototype liquid metal spallation target MEGAPIE irradiated in 2006 at PSI were analysed using γ-spectrometry. A variety of radionuclides formed by reaction of the target material, lead–bismuth eutectic (LBE), with the proton beam and secondary particles were identified. While nuclides representing the target material itself (207Bi) and nuclides of noble metals were found in LBE samples throughout the target, nuclides of electropositive metals were found to be quantitatively deposited on free surfaces and material interfaces within the target system. This behaviour is analysed in more detail based on results obtained for three nuclides representing groups of elements with distinct chemical behaviour, namely 207Bi, 194Hg/Au and 173Lu. Quantitative analysis results are given and compared with predictions obtained using nuclear physics calculations for those nuclides showing rather homogeneous distribution within the target. Possible reasons for the separation of radionuclides from the liquid metal and their deposition on surfaces are given, and consequences arising for nuclear facilities utilizing liquid metals are discussed.

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Gas diffusion research in soils covers, to a large extent, the transport behavior of practically insoluble gases. We extend the mathematical description of gas transport to include reactive gaseous components that hydrolyze in water such as SO2 and CO2. The path between the free atmosphere and the microporous niches is modeled by assuming penetration through gas-filled macropores, air-water phase transfer, and diffusion and speciation in the liquid phase. For hydrolyzable gases, the rate of mass transfer into and the total absorption capacity of the soil solution may be high. Both the capacity and the transfer rate are influenced by the soil-solution pH; for high pH, they become extremely high for SO2. The soil absorption of such gases is also influenced by soil structure. Well-aerated, near-neutral soils are a potentially important sink for SO2.

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The interaction between sensory rhodopsin II (SRII) and its transducer HtrII was studied by the time-resolved laser-induced transient grating method using the D75N mutant of SRII, which exhibits minimal visible light absorption changes during its photocycle, but mediates normal phototaxis responses. Flash-induced transient absorption spectra of transducer-free D75N and D75N joined to 120 amino-acid residues of the N-terminal part of the SRII transducer protein HtrII (DeltaHtrII) showed only one spectrally distinct K-like intermediate in their photocycles, but the transient grating method resolved four intermediates (K(1)-K(4)) distinct in their volumes. D75N bound to HtrII exhibited one additional slower kinetic species, which persists after complete recovery of the initial state as assessed by absorption changes in the UV-visible region. The kinetics indicate a conformationally changed form of the transducer portion (designated Tr*), which persists after the photoreceptor returns to the unphotolyzed state. The largest conformational change in the DeltaHtrII portion was found to cause a DeltaHtrII-dependent increase in volume rising in 8 micros in the K(4) state and a drastic decrease in the diffusion coefficient (D) of K(4) relatively to those of the unphotolyzed state and Tr*. The magnitude of the decrease in D indicates a large structural change, presumably in the solvent-exposed HAMP domain of DeltaHtrII, where rearrangement of interacting molecules in the solvent would substantially change friction between the protein and the solvent.

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Currently, there are no molecular biomarkers that guide treatment decisions for patients with head and neck squamous cell carcinoma (HNSCC). Several retrospective studies have evaluated TP53 in HNSCC, and results have suggested that specific mutations are associated with poor outcome. However, there exists heterogeneity among these studies in the site and stage of disease of the patients reviewed, the treatments rendered, and methods of evaluating TP53 mutation. Thus, it remains unclear as to which patients and in which clinical settings TP53 mutation is most useful in predicting treatment failure. In the current study, we reviewed the records of a cohort of patients with advanced, resectable HNSCC who received surgery and post-operative radiation (PORT) and had DNA isolated from fresh tumor tissue obtained at the time of surgery. TP53 mutations were identified using Sanger sequencing of exons 2-11 and the associated splice regions of the TP53 gene. We have found that the group of patients with either non-disruptive or disruptive TP53 mutations had decreased overall survival, disease-free survival, and an increased rate of distant metastasis. When examined as an independent factor, disruptive mutation was strongly associated with the development of distant metastasis. As a second aim of this project, we performed a pilot study examining the utility of the AmpliChip® p53 test as a practical method for TP53 sequencing in the clinical setting. AmpliChip® testing and Sanger sequencing was performed on a separate cohort of patients with HNSCC. Our study demonstrated the ablity of the AmpliChip® to call TP53 mutation from a single formalin-fixed paraffin-embedded slide. The results from AmpliChip® testing were identical with the Sanger method in 11 of 19 cases, with a higher rate of mutation calls using the AmpliChip® test. TP53 mutation is a potential prognostic biomarker among patients with advanced, resectable HNSCC treated with surgery and PORT. Whether this subgroup of patients could benefit from the addition of concurrent or induction chemotherapy remains to be evaluated in prospective clinical trials. Our pilot study of the p53 AmpliChip® suggests this could be a practical and reliable method of TP53 analysis in the clinical setting.

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The World Trade Organization (WTO) is one of the most judicialized dispute settlement systems in international politics. While a general appreciation has developed that the system has worked quite well, research has not paid sufficient attention to the weakest actors in the system. This paper addresses the puzzle of missing cases of least-developed countries initiating WTO disputes settlement procedures. It challenges the existing literature on developing countries in WTO dispute settlement which predominantly focuses on legal capacity and economic interests. The paper provides an argument that the small universe of ‘actionable cases’, the option of free riding and the assessment of the perceived opportunity costs related to other foreign policy priorities better explain the absence of cases. In addition (and somewhat counterintuitively), we argue that the absence of cases is not necessarily bad news and shows how the weakest actors can use the dispute settlement system in a ‘lighter version’ or in indirect ways. The argument is empirically assessed by conducting a case study on four West African cotton-producing countries (C4) and their involvement in dispute settlement.

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Cultural models of the domains healing and health are important in how people understand health and their behavior regarding it. The biomedicine model has been predominant in Western society. Recent popularity of holistic health and alternative healing modalities contrasts with the biomedical model and the assumptions upon which that model has been practiced. The holistic health movement characterizes an effort by health care providers and others such as nurses to expand the biomedical model and has often incorporated alternative modalities. This research described and compared the cultural models of healing of professional nurses and alternative healers. A group of nursing faculty who promote a holistic model were compared to a group of healers using healing touch. Ethnographic methods of participant observation, free listing and pile sort were used. Theoretical sampling in the free listings reached saturation at 18 in the group of nurses and 21 in the group of healers. Categories consistent for both groups emerged from the data. These were: physical, mental, attitude, relationships, spiritual, self management, and health seeking including biomedical and alternative resources. The healers had little differentiation between the concepts health and healing. The nurses, however, had more elements in self management for health and in health seeking for healing. This reflects the nurse's role in facilitating the shift in locus of responsibility between health and healing. The healers provided more specific information regarding alternative resources. The healer's conceptualization of health was embedded in a spiritual belief system and contrasted dramatically with that of biomedicine. The healer's models also contrasted with holistic health in the areas of holism, locus of responsibility, and dealing with uncertainty. The similarity between the groups and their dissimilarity to biomedicine suggest a larger cultural shift in beliefs regarding health care. ^

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The discovery and characterization of oncofetal proteins have led to significant advances in early cancer diagnosis and therapeutic monitoring of patients undergoing cancer chemotherapy. These tumor-associated antigens are presently measured by sensitive, specific immunoassay techniques based on the detection of minute amounts of labeled antigen or antibody incorporated into immune complexes, which must be isolated from free antigen and antibody.^ Since there are several disadvantages with using radioisotopes, the most common immunolabel, one major objective was to prepare covalently coupled enzyme-antibody conjugates and evaluate their use as a practical alternative to radiolabeled immune reagents. An improved technique for the production of enzyme-antibody conjugates was developed that involves oxidizing the carbohydrate moieties on a glycoprotein enzyme, then introducing antibody in the presence of polyethylene glycol (PEG). Covalent enzyme-antibody conjugates involving alkaline phosphatase and amyloglucosidase were produced and characterized.^ In order to increase the sensitivity of detecting the amyloglucosidase-antibody conjugate, an enzyme cycling assay was developed that measures glucose, the product of maltose cleavage by amyloglucosidase, in the picomole range. The increased sensitivity obtained by combined usage of the amyloglucosidase-antibody conjugate and enzyme cycling assay was then compared to that of conventional enzyme immunoassay (EIA).^ For immune complex isolation, polystyrene tubes and protein A-bearing Staphylococcus aureus were evaluated as solid phase matrices, upon which antibodies can be immobilized. A sandwich-type EIA, using antibody-coated S. aureus, was developed that measures human albumin (HSA) in the nanogram range. The assay, using an alkaline phosphatase-anti-HSA conjugate, was applied to the determination of HSA in human urine and evaluated extensively for its clinical applicability.^ Finally, in view of the clinical significance of alpha-fetoprotein (AFP) as an oncofetal antigen and the difficulty with its purification for use as an immunogen and assay standard, a chemical purification protocol was developed that resulted in a high yield of immunochemically pure AFP. ^

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Cultural protectionism has been an element of national and foreign policies, as an extension of state sovereignty expressed both in a defensive and offensive manner. While the generic protectionist formula in the sense of restraining trade between states through measures such as import tariffs or quotas and through privileging domestic production has somewhat disintegrated over time under the rationale for free trade and the strong practical evidence of its benefits, the particular case of cultural protectionism has persevered. As we reveal in this paper, however, it has been modified, or at least its rhetoric has changed. The enquiry into the notion of cultural protectionism or cultural diversity, as the current political jargon would have it, is but one of the paper’s objectives. Its second and certainly more ambitious goal is the search for the normative dimensions of cultural diversity policies in the global digital space, asking what adjustments are needed and how feasible the entire project of diversity regulation in this environment may be. Taking into account the specificities of cyberspace and in a forward-looking manner, we propose some adjustments to current media policy practices that could better serve the goal of a sustainably diverse cultural environment.

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Coilin is the signature protein of the Cajal body (CB), a nuclear suborganelle involved in the biogenesis of small nuclear ribonucleoproteins (snRNPs). Newly imported Sm-class snRNPs are thought to traffic through CBs before proceeding to their final nuclear destinations. Loss of coilin function in mice leads to significant viability and fertility problems. Coilin interacts directly with the spinal muscular atrophy (SMA) protein via dimethylarginine residues in its C-terminal domain. Although coilin hypomethylation results in delocalization of survival of motor neurons (SMN) from CBs, high concentrations of snRNPs remain within these structures. Thus, CBs appear to be involved in snRNP maturation, but factors that tether snRNPs to CBs have not been described. In this report, we demonstrate that the coilin C-terminal domain binds directly to various Sm and Lsm proteins via their Sm motifs. We show that the region of coilin responsible for this binding activity is separable from that which binds to SMN. Interestingly, U2, U4, U5, and U6 snRNPs interact with the coilin C-terminal domain in a glutathione S-transferase (GST)-pulldown assay, whereas U1 and U7 snRNPs do not. Thus, the ability to interact with free Sm (and Lsm) proteins as well as with intact snRNPs, indicates that coilin and CBs may facilitate the modification of newly formed snRNPs, the regeneration of 'mature' snRNPs, or the reclamation of unassembled snRNP components.

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The paper argues for a distinction between sensory-and conceptual-information storage in the human information-processing system. Conceptual information is characterized as meaningful and symbolic, while sensory information may exist in modality-bound form. Furthermore, it is assumed that sensory information does not contribute to conscious remembering and can be used only in data-driven process reptitions, which can be accompanied by a kind of vague or intuitive feeling. Accordingly, pure top-down and willingly controlled processing, such as free recall, should not have any access to sensory data. Empirical results from different research areas and from two experiments conducted by the authors are presented in this article to support these theoretical distinctions. The experiments were designed to separate a sensory-motor and a conceptual component in memory for two-digit numbers and two-letter items, when parts of the numbers or items were imaged or drawn on a tablet. The results of free recall and recognition are discussed in a theoretical framework which distinguishes sensory and conceptual information in memory.

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Objective: to determine the short- and long-term effects of resistance training on muscle strength, psychological well-being, control-beliefs, cognitive speed and memory in normally active elderly people. Methods: 46 elderly people (mean age 73.2 years; 18 women and 28 men), were randomly assigned to training and control groups (n = 23 each). Pre- and post-tests were administered 1 week before and 1 week after the 8-week training intervention. The training sessions, performed once a week, consisted of a 10 min warm-up phase and eight resistance exercises on machines. Results: there was a significant increase in maximum dynamic strength in the training group. This training effect was associated with a significant decrease in self-attentiveness, which is known to enhance psychological well-being. No significant changes could be observed in control-beliefs. Modest effects on cognitive functioning occurred with the training procedure: although there were no changes in cognitive speed, significant pre/post-changes could be shown in free recall and recognition in the experimental group. A post-test comparison between the experimental group and control group showed a weak effect for recognition but no significant differences in free recall. Significant long-term effects were found in the training group for muscular strength and memory performance (free recall) 1 year later. Conclusion: an 8-week programme of resistance training lessens anxiety and self-attentiveness and improves muscle strength.