991 resultados para NEGATIVE DIFFERENTIAL CONDUCTIVITY


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Purpose. This study examined benefit finding in MS carers including the dimensionality of benefit finding, relations between carer and care recipient benefit finding, and the effects of carer benefit finding on carer positive and negative adjustment domains. Method. A total of 267 carers and their care recipients completed questionnaires at Time 1 and 3 months later, Time 2 (n=155). Illness data were collected at Time 1, and number of problems, stress appraisal, benefit finding, negative (global distress, negative affect) and positive (life satisfaction, positive affect, dyadic adjustment) adjustment domains were measured at Time 2. Results. Qualitative data revealed seven benefit finding themes, two of which were adequately represented by the Benefit Finding Scale (BFS) [1] (Mohr et al. Health Psychology 1999; 18: 376). Factor analyses indicated two factors (Personal Growth, Family Relations Growth) which were psychometrically sound and showed differential relations with illness and adjustment domains. Although care recipients reported higher levels of benefit finding than carers, their benefit finding reports regarding personal growth were correlated. The carer BFS factors were positively related to carer and care recipient dyadic adjustment. Care recipient benefit finding was unrelated to carer adjustment domains. After controlling for the effects of demographics, care recipient characteristics, problems and appraisal, carer benefit finding was related to carer positive adjustment domains and unrelated to carer negative adjustment domains. Conclusion. Findings support the role of benefit finding in sustaining positive psychological states and the communal search for meaning within carer-care recipient dyads.

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Networked information and communication technologies are rapidly advancing the capacities of governments to target and separately manage specific sub-populations, groups and individuals. Targeting uses data profiling to calculate the differential probabilities of outcomes associated with various personal characteristics. This knowledge is used to classify and sort people for differentiated levels of treatment. Targeting is often used to efficiently and effectively target government resources to the most disadvantaged. Although having many benefits, targeting raises several policy and ethical issues. This paper discusses these issues and the policy responses governments may take to maximise the benefits of targeting while ameliorating the negative aspects.

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Investigations of relationships between the specific personality variable, locus of control (LOC, Rotter, 1966) and driver behaviour or accidents have returned contrasting results. Review suggests dependence on gender or experience characteristics of participants, suggesting these factors interact with LOC to influence driving. Relationships were investigated in terms of influence on the eight driving styles of the Multidimensional Driving Style Inventory (MDSI, Taubman-Ben-Ari, Mikulincer & Gillarth, 2004) in young drivers (18-29 years). Gender and LOC differences in driving styles previously related to accidents were proposed. It was also proposed that driving experience influences driving style, and LOC influences effect of driving experience. Gender differences were found for dissociative, anxious, patient, risky, angry and high velocity styles. Women had more external LOC than men, and driver stress styles increased with more external LOC, but reduced with increased driving experience, but so did patient style. High velocity style increased with experience. Controlling for LOC revealed important gender differences in effect of experience: positive effects for men (reducing angry and high velocity, increasing carefulness) and negative effects for women (increasing angry and higher velocity, reducing carefulness). Findings suggest negative influence of high internal LOC on young men in terms of its interaction with experience.

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The thesis is divided into four chapters. They are: introduction, experimental, results and discussion about the free ligands and results and discussion about the complexes. The First Chapter, the introductory chapter, is a general introduction to the study of solid state reactions. The Second Chapter is devoted to the materials and experimental methods that have been used for carrying out tile experiments. TIle Third Chapter is concerned with the characterisations of free ligands (Picolinic acid, nicotinic acid, and isonicotinic acid) by using elemental analysis, IR spectra, X-ray diffraction, and mass spectra. Additionally, the thermal behaviour of free ligands in air has been studied by means of thermogravimetry (TG), derivative thermogravimetry (DTG), and differential scanning calorimetry (DSC) measurements. The behaviour of thermal decomposition of the three free ligands was not identical Finally, a computer program has been used for kinetic evaluation of non-isothermal differential scanning calorimetry data according to a composite and single heating rate methods in comparison with the methods due to Ozawa and Kissinger methods. The most probable reaction mechanism for the free ligands was the Avrami-Erofeev equation (A) that described the solid-state nucleation-growth mechanism. The activation parameters of the decomposition reaction for free ligands were calculated and the results of different methods of data analysis were compared and discussed. The Fourth Chapter, the final chapter, deals with the preparation of cobalt, nickel, and copper with mono-pyridine carboxylic acids in aqueous solution. The prepared complexes have been characterised by analyses, IR spectra, X-ray diffraction, magnetic moments, and electronic spectra. The stoichiometry of these compounds was ML2x(H20), (where M = metal ion, L = organic ligand and x = water molecule). The environments of cobalt, nickel, and copper nicotinates and the environments of cobalt and nickel picolinates were octahedral, whereas the environment of copper picolinate [Cu(PA)2] was tetragonal. However, the environments of cobalt, nickel, and copper isonicotinates were polymeric octahedral structures. The morphological changes that occurred throughout the decomposition were followed by SEM observation. TG, DTG, and DSC measurements have studied the thermal behaviour of the prepared complexes in air. During the degradation processes of the hydrated complexes, the crystallisation water molecules were lost in one or two steps. This was also followed by loss of organic ligands and the metal oxides remained. Comparison between the DTG temperatures of the first and second steps of the dehydration suggested that the water of crystallisation was more strongly bonded with anion in Ni(II) complexes than in the complexes of Co(II) and Cu(II). The intermediate products of decomposition were not identified. The most probable reaction mechanism for the prepared complexes was also Avrami-Erofeev equation (A) characteristic of solid-state nucleation-growth mechanism. The tempemture dependence of conductivity using direct current was determined for cobalt, nickel, Cl.nd copper isonicotinates. An activation energy (ΔΕ), the activation energy (ΔΕ ) were calculated.The ternperature and frequency dependence of conductivity, the frequency dependence of dielectric constant, and the dielectric loss for nickel isonicotinate were determined by using altemating current. The value of s paralneter and the value of'density of state [N(Ef)] were calculated. Keyword Thermal decomposition, kinetic, electrical conduclion, pyridine rnono~ carboxylic acid, cOlnplex, transition metal compJex.

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Sepsis continues to be a major cause of morbidity and mortality as it can readily lead tosevere sepsis, septic shock, multiple organ failure and death. The onset can be rapid and difficult to define clinically. Despite the numerous candidate markers proposed in the literature, to date a serum marker for sepsis has not been found. The aim of this study was to assay the serum of clinically diagnosed patients with eithera Gram-negative or Gram- positive bacterial sepsis for elevated levels of nine potentialmarkers of sepsis, using commercially produced enzyme linked immunosorbent assays(ELISA). The purpose was to find a test marker for sepsis that would be helpful toclinicians in cases of uncertain sepsis and consequently expose false positive BC'scaused by skin or environmental contaminants. Nine test markers were assayed including IL-6, IL-I 0, ILI2, TNF-α, lipopolysaccharide binding protein, procalcitonin, sE-selectin, sICAM -1 and a potential differential marker for Gram-positive sepsis- anti-lipid S antibody. A total of 445 patients were enrolled into this study from the Queen Elizabeth Hospital and Selly Oak Hospital (Birmingham). The results showed that all the markers were elevated in patients with sepsis and that patients with a Gram-negative sepsis consistently produced higher median/range serum levels than those with a Gram-positive sepsis. No single marker was able to identify all the septic patients. Combining two markers caused the sensitivities and specificities for a diagnosis of sepsis to increase to within a 90% to 100% range. By a process of elimination the markers that survived into the last phase were IL-6 with sICAM -1, and anti-lipid S IgG assays Defining cut-off levels for a diagnosis of sepsis became problematic and a semi-blind trial was devised to test the markers in the absence of both clinical details and positive blood cultures. Patients with pyrexia of unknown origin and negative BC were included in this phase (4). The results showed that IL-6 with sICAM-l are authentic markers of sepsis. There was 82% agreement between the test marker diagnosis and the clinical diagnosis for sepsis in patients with a Gram-positive BC and 78% agreement in cases of Gram-negative Be. In the PUO group the test markers identified 12 cases of sepsis and the clinical diagnosis 15. The markers were shown to differentiate between early sepsis and sepsis, inflammatory responses and infection. Anti-lipid S with IL-6 proved be a sensitive marker for Gram-positive infections/sepsis.

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Background: There is evidence showing that men and women differ with regard to the processing of emotional information. However, the mechanisms behind these differences are not fully understood. Method: The sample comprised of 275 (167 female) right-handed, healthy participants, recruited from the community. We employed a customized affective priming task, which consisted of three subtests, differing in the modality of the prime (face, written word, and sound). The targets were always written words of either positive or negative valence. The priming effect was measured as reaction time facilitation in conditions where both prime and target were emotional (of the same positive or negative valence) compared with conditions where the emotional targets were preceded by neutral primes. Results: The priming effect was observed across all three modalities, with an interaction of gender by valence: the priming effect in the emotionally negative condition in male participants was stronger compared with females. This was accounted for by the differential priming effect within the female group where priming was significantly smaller in the emotionally negative conditions compared with the positive conditions. The male participants revealed a comparable priming effect across both the emotionally negative and positive conditions. Conclusion: Reduced priming in negative conditions in women may reflect interference processes due to greater sensitivity to negative valence of stimuli. This in turn could underlie the gender-related differences in susceptibility to emotional disorders.

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Mathematics Subject Classification: 35J05, 35J25, 35C15, 47H50, 47G30

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2010 Mathematics Subject Classification: 34A30, 34A40, 34C10.

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Triple Negative Breast Cancer (TNBC) is defined by the lack of ERα, PR expression and HER2 overexpression and is the breast cancer subtype with the poorest clinical outcomes. Our aim was to identify genes driving TNBC proliferation and/or survival which could represent novel therapeutic targets. We performed microarray profiling of primary TNBCs and generated differential genelists based on clinical outcomes following the chemotherapy regimen FEC (5-Fluorouracil/Epirubicin/Cyclophosphamide -‘good’ outcome no relapse > 3 years; ‘poor’ outcome relapse < 3 years). Elevated expression of thromboxane A2 receptor (TBXA2R) was observed in ‘good’ outcome TNBCs. TBXA2R expression was higher specifically in TNBC cell lines and TBXA2R knockdowns consistently showed dramatic cell killing in TNBC cells. TBXA2R mRNA and promoter activities were up-regulated following BRCA1 knockdown, with c-Myc being required for BRCA1-mediated transcriptional repression. We demonstrated that TBXA2R enhanced TNBC cell migration, invasion and activated Rho signalling, phenotypes which could be reversed using Rho-associated Kinase (ROCK) inhibitors. TBXA2R also protected TNBC cells from DNA damage by negatively regulating reactive oxygen species levels. In summary, TBXA2R is a novel breast cancer-associated gene required for the survival and migratory behaviour of a subset of TNBCs and could provide opportunities to develop novel, more effective treatments.

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Thesis (Ph.D.)--University of Washington, 2016-08

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La maladie d’Alzheimer (MA) se caractérise pathologiquement par l’accumulation de plaques amyloïde dans le cerveau. La tomographie par émission de positrons (TEP) permet d’imager les plaques amyloïde in vivo. Le but de ce projet est d’évaluer le rôle de la TEP amyloïde dans le processus diagnostique de la MA dans des cas de démences atypiques. Le deuxième but de ce projet est de déterminer l’impact de la révélation d’un diagnostic plus certain chez les proches aidants. 28 patients sans diagnostic malgré une investigation exhaustive ont été sélectionnées et imagées avec le traceur amyloïde 18F-NAV4694 (âge 59,3 ans, é-t. 5,8; MMSE 21.4, é-t 6.0). Les neurologues référents documentaient par la suite tout changement de niveau de certitude, de diagnostic, de traitement et/ou de prise en charge. Les proches aidants consentants ont été rencontrés subséquemment, et un questionnaire avec une échelle de Likert a été utilisé afin de documenter l’impact de l’imagerie leur perception de la maladie. Notre cohorte a été également divisée entre amyloïde positifs (14/28) et négatifs (14/28). Un changement de diagnostic a lieu dans 9/28 cas (32,1% :17.8% ont changé de MA à non-MA, 14,3% de non-MA à MA). Il y avait une augmentation significative (p<0,05) de 44% dans la certitude du neurologue suite à cet examen. Un changement de prise en charge a été obtenu dans 20/28 (71,4%) des cas. Bien que non significatifs statistiquement, un impact favorable sur les proches-aidants a été noté. Cette étude suggère que l’imagerie amyloïde a un rôle bénéfique dans les cas de démences atypiques n’ayant pu être élucidés avec les techniques d’investigations actuellement recommandées. De plus, le processus a été perçu positivement par les proches aidants, notamment en encourageant du temps de qualité avec leurs personnes chères. Ceci illustre un rôle prometteur des biomarqueurs, qui sont de plus en plus explorés.

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Severe dengue pathogenesis is not fully understood, but high levels of proinflammatory cytokines have been associated with dengue disease severity. In this study, the cytokine levels in 171 sera from Mexican patients with primary dengue fever (DF) and dengue haemorrhagic fever (DHF) from dengue virus (DENV) 1 (n = 116) or 2 (n = 55) were compared. DF and DHF were defined according to the patient’s clinical condition, the primary infections as indicated by IgG enzymatic immunoassay negative results, and the infecting serotype as assessed by real-time reverse transcriptionpolymerase chain reaction. Samples were analysed for circulating levels of interleukin (IL)-12p70, interferon (IFN)-γ, tumour necrosis factor (TNF)-α, IL-6, and IL-8 using a commercial cytometric bead array. Significantly higher IFN-γ levels were found in patients with DHF than those with DF. However, significantly higher IL-12p70, TNF-α, and IL-6 levels were associated with DHF only in patients who were infected with DENV2 but not with DENV1. Moreover, patients with DF who were infected with DENV1 showed higher levels of IL-12p70, TNF-α, and IL-6 than patients with DHF early after-fever onset. The IL-8 levels were similar in all cases regardless of the clinical condition or infection serotype. These results suggest that the association between high proinflammatory cytokine levels and dengue disease severity does not always stand, and it once again highlights the complex nature of DHF pathogenesis.

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Interaction between the complement system and carbon nanotubes (CNTs) can modify their intended biomedical applications. Pristine and derivatised CNTs can activate complement primarily via the classical pathway which enhances uptake of CNTs and suppresses pro-inflammatory response by immune cells. Here, we report that the interaction of C1q, the classical pathway recognition molecule, with CNTs involves charge pattern and classical pathway activation that is partly inhibited by factor H, a complement regulator. C1q and its globular modules, but not factor H, enhanced uptake of CNTs by macrophages and modulated the pro-inflammatory immune response. Thus, soluble complement factors can interact differentially with CNTs and alter the immune response even without complement activation. Coating CNTs with recombinant C1q globular heads offers a novel way of controlling classical pathway activation in nanotherapeutics. Surprisingly, the globular heads also enhance clearance by phagocytes and down-regulate inflammation, suggesting unexpected complexity in receptor interaction. From the Clinical Editor: Carbon nanotubes (CNTs) maybe useful in the clinical setting as targeting drug carriers. However, it is also well known that they can interact and activate the complement system, which may have a negative impact on the applicability of CNTs. In this study, the authors functionalized multi-walled CNT (MWNT), and investigated the interaction with the complement pathway. These studies are important so as to gain further understanding of the underlying mechanism in preparation for future use of CNTs in the clinical setting.

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In order to access the effect of the lakes in the atmospheric electrical field, measurements have been carried out near a large man-made lake in southern Portugal, the Alqueva reservoir, during the ALqueva hydro-meteorological EXperiment 2014. The purpose of these conjoint experiments was to study the impact of the Alqueva reservoir on the atmosphere, in particular on the local atmospheric electric environment by comparing measurements taken in the proximity of the lake. Two stations 10 km apart were used, as they were located up- and down-wind of the lake (Amieira and Parque Solar, respectively), in reference to the dominant northwestern wind direction. The up-wind station shows lower atmospheric electric potential gradient (PG) values than the ones observed in the down-wind station between 12 and 20 UTC. The difference in the atmospheric electric PG between the up-wind and the down-wind station is ~30 V/m during the day. This differential occurs mainly during the development of a lake breeze, between 10 and 18 UTC, as a consequence of the surface temperature gradient between the surrounding land and the lake water. In the analysis presented, a correlation is found between the atmospheric electric PG differences and both wind speed and temperature gradients over the lake, thus supporting the influence of the lake breeze over the observed PG variation in the two stations. Two hypotheses are provided to explain this observation: (1) The air that flows from the lake into the land station is likely to increase the local electric conductivity through the removal of ground dust and the transport of cleaner air from higher altitudes with significant light ion concentrations. With such an increase in conductivity, it is expected to see a reduction of the atmospheric electric PG; (2) the resulting air flow over the land station carries negative ions formed by wave splashing in the lake's water surface, as a result of the so-called balloelectric effect. These negative ions will form a space-charge density (SCD) that can reduce the atmospheric electric PG. A formulation is derived here in order to estimate the local SCD.