964 resultados para 250406 Immunological and Bioassay Methods
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Chlorine is the most commonly used agent for general disinfection, particularly for microbial growth control in drinking water distribution systems. The goals of this study were to understand the effects of chlorine, as sodium hypochlorite (NaOCl), on bacterial membrane physicochemical properties (surface charge, surface tension and hydrophobicity) and on motility of two emerging pathogens isolated from drinking water, Acinetobacter calcoaceticus and Stenotrophomonas maltophilia. The effects of NaOCl on the control of single and dual-species monolayer adhered bacteria (2 h incubation) and biofilms (24 h incubation) was also assessed. NaOCl caused significant changes on the surface hydrophobicity and motility of A. calcoaceticus, but not of S. maltophilia. Planktonic and sessile S. maltophilia were significantly more resistant to NaOCl than A. calcoaceticus. Monolayer adhered co-cultures of A. calcoaceticus-S. maltophilia were more resilient than the single species. Oppositely, dual species biofilms were more susceptible to NaOCl than their single species counterparts. In general, biofilm removal and killing demonstrated to be distinct phenomena: total bacterial viability reduction was achieved even if NaOCl at the higher concentrations had a reduced removal efficacy, allowing biofilm reseed. In conclusion, understanding the antimicrobial susceptibility of microorganisms to NaOCl can contribute to the design of effective biofilm control strategies targeting key microorganisms, such as S. maltophilia, and guarantying safe and high-quality drinking water. Moreover, the results reinforce that biofilms should be regarded as chronic contaminants of drinking water distribution systems and accurate methods are needed to quantify their presence as well as strategies complementary/alternative to NaOCl are required to effectively control the microbiological quality of drinking water.
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Esta investigación propone aproximarse al conocimiento y comprensión de los diversos mecanismos de movilidad social en Villa La Tela barrios adyacentes (ciudad de Córdoba). Si bien las poblaciones objetivo poseen diferentes niveles de vida, este proyecto no se propone la comparación entre ambos sectores urbanos, sino la identificación de diversos patrones de movilidad social vigentes. Se intenta también aproximarse indirectamente al esquema de estratificación social vigente en la ciudad de Córdoba. El equipo se propone avanzar en la definición de una estrategia metodológica que permita comprender de una manera integral los diversos mecanismos de movilidad social. Se propone articular una triangulación de métodos cuantitativos y cualitativos que aproveche las fortalezas de cada enfoque para efectuar una mirada multidisciplinaria de las condiciones de vida de la población en estudio. Se intenta también aprovechar la inserción que ya tienen algunos de los investigadores del equipo en los barrios, a fin de aportar conocimientos útiles a las organizaciones que realizan actividades de intervención social. El trabajo se propone en tres fases constituidas por tres instancias que no necesariamente se corresponden con tiempos cronológicos: análisis de información secundaria (censos de población, relevamientos de organismos gubernamentales y civiles) y de resultados de investigaciones previas; en otra fase se generará un espacio recreativo en la comunidad que permita identificar las percepciones subjetivas de los actores locales en relación a las condiciones de vida y la experiencia de movilidad social (etnodrama, etnografía fotográfica); finalmente se realizará una fase de trabajo de encuestas y entrevistas en profundidad a partir de los insumos producidos en las dos fases antes mencionadas. Se tomará para ello, como unidad de análisis socio-económica a los hogares, considerados como el espacio físico y social desde el cual se diseñan e implementan las estrategias familiares de vida de sus miembros. Se considera que el proyecto puede transferir los resultados -parciales y finales- alcanzados a las instituciones intervinientes en los barrios considerados. Esta transferencia constituye una actividad de extensión concreta, dado que las intervenciones en marcha están destinadas a mejorar las condiciones de vida de la población en términos materiales y culturales. La acción sinérgica entre las diversas instituciones que intervienen o investigan sobre estas comunidades es un compromiso, ya que de ello depende la calidad del impacto en las propias comunidades. En este sentido, la descripción de las experiencias intergeneracionales de movilidad social de los hogares y su significación subjetiva, puede considerarse de interés tanto para las instituciones como para la comunidad misma. De esta manera se espera devolver a las comunidades lo que éstas le ofrezcan al equipo de investigación, como flujo de intercambio recíproco de conocimiento y desarrollo humano. Desde el punto de vista metodológico, el equipo espera realizar una evaluación de los distintos abordajes cuantitativos y cualitativos a escala microsocial, a fin de realizar propuestas válidas para nuevas investigaciones en ámbitos locales. This research proposes to approach the knowledge and understanding of the various mechanisms of social mobility in adjacent neighborhoods of Villa La Tela (Cordoba, Argentina). Although the target populations have different levels of life, this project does not intend to compare urban areas, but the identification of different patterns of social mobility nowadays. Indirect approach is also intended to outline the existing social stratification in Cordoba city. We plan to define a methodological approach based on triangulation of quantitative and qualitative methods, exploiting the strengths of each approach to make a multidisciplinary vision of the population living conditions. Project proposes phases consisting of three instances, that do not necessarily correspond with chronological time: 1) secondary data analysis (population censuses, surveys of government agencies and civilian organizations) and previous research results; 2) promotion of a recreation space in the community to identify the subjective perceptions of local actors in relation to living conditions and experience of social mobility; 3) finally there will be a phase of survey work and deep interviews from inputs produced in the two phases mentioned above. Households will be taken as socio-economic unit, also considered as social and physical space where family strategies of life are designed and implemented by its members. We considere this project can transfer the obtained results to the institutions involved in the concerned districts. This transfer is a specific outreach activity, since the interventions in place are aimed to improving the living conditions of population in material and cultural terms.
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Diagnosis, prognosis and evaluation of death risk in Chagas cardiomyopathy still constitute a challenge due to the diversity of manifestations, which determine the importance of using echocardiography, tissue Doppler and biomarkers. To evaluate, within a systematic review, clinical and echocardiographic profiles of patients with chronic chagasic cardiomyopathy, which may be related to worse prognosis and major mortality risk. To perform the systematic review, we used Medline (via PubMed), LILACS and SciELO databases to identify 82 articles published from 1991 to 2012, with the following descriptors: echocardiography, mortality and Chagas disease. We selected 31 original articles, involving diagnostic and prognostic methods. The importance of Chagas disease has increased due to its emergence in Europe and United States, but most evidence came from Brazil. Among the predictors of worse prognosis and higher mortality risk are morphological and functional alterations in the left and right ventricles, evaluated by conventional echocardiography and tissue Doppler, as well as the increase in brain natriuretic peptide and troponin I concentrations. Recently, the evaluations of dyssynchrony, dysautonomia, as well as strain, strain rate and myocardial twisting were added to the diagnostic arsenal for the early differentiation of Chagas cardiomyopathy. Developments in imaging and biochemical diagnostic procedures have enabled more detailed cardiac evaluations, which demonstrate the early involvement of both ventricles, allowing a more accurate assessment of the mortality risk in Chagas disease.
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Background: Clinical in-stent restenosis (CISR) is the main limitation of coronary angioplasty with stent implantation. Objective: Describe the clinical and angiographic characteristics of CISR and the outcomes over a minimum follow-up of 12 months after its diagnosis and treatment. Methods: We analyzed in 110 consecutive patients with CISR the clinical presentation, angiographic characteristics, treatment and combined primary outcomes (cardiovascular death, nonfatal acute myocardial infarction [AMI]) and combined secondary (unstable angina with hospitalization, target vessel revascularization and target lesion revascularization) during a minimal follow-up of one year. Results: Mean age was 61 ± 11 years (68.2% males). Clinical presentations included acute coronary syndrome (ACS) in 62.7% and proliferative ISR in 34.5%. CISR was treated with implantation of drug-eluting stents (DES) in 36.4%, Bare Metal Stent (BMS) in 23.6%, myocardial revascularization surgery in 18.2%, balloon angioplasty in 15.5% and clinical treatment in 6.4%. During a median follow-up of 19.7 months, the primary outcome occurred in 18 patients, including 6 (5.5%) deaths and 13 (11.8%) AMI events. Twenty-four patients presented a secondary outcome. Predictors of the primary outcome were CISR with DES (HR = 4.36 [1.44–12.85]; p = 0.009) and clinical treatment for CISR (HR = 10.66 [2.53–44.87]; p = 0.001). Treatment of CISR with BMS (HR = 4.08 [1.75–9.48]; p = 0.001) and clinical therapy (HR = 6.29 [1.35–29.38]; p = 0.019) emerged as predictors of a secondary outcome. Conclusion: Patients with CISR present in most cases with ACS and with a high frequency of adverse events during a medium-term follow-up.
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Abstract Background: Both poor aerobic fitness and obesity, separately, are associated with abnormal lipid profiles. Objective: To identify possible relationships of dyslipidemia with cardiorespiratory fitness and obesity, evaluated together, in children and adolescents. Methods: This cross-sectional study included 1,243 children and adolescents (563 males and 680 females) between 7 and 17 years of age from 19 schools. Obesity was assessed using body mass index (BMI) measurements, and cardiorespiratory fitness was determined via a 9-minute run/walk test. To analyze the lipid profile of each subject, the following markers were used: total cholesterol, cholesterol fractions (high-density lipoprotein and low-density lipoprotein) and triglycerides. Data were analyzed using SPSS v. 20.0, via prevalence ratio (PR), using the Poisson regression. Results: Dyslipidemia is more prevalent among unfit/overweight-obese children and adolescents compared with fit/underweight-normal weight boys (PR: 1.25; p = 0.007) and girls (PR: 1.30, p = 0.001). Conclusions: The prevalence of dyslipidemia is directly related to both obesity and lower levels of cardiorespiratory fitness.
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Abstract Background: The epidemiological profile of mortality in a population is important for the institution of measures to improve health care and reduce mortality Objective: To estimate mortality rates and the proportional mortality from cardiovascular diseases and malformations of the circulatory system in children and adolescents. Methods: This is a descriptive study of mortality from cardiovascular diseases, malformations of the circulatory system, from all causes, ill-defined causes and external causes in children and adolescents in the state of Rio de Janeiro from 1996 to 2012. Populations were obtained from the Brazilian Institute of Geography and Statistics (Instituto Brasileiro de Geografia e Estatística - IBGE) and deaths obtained from the Department of Informatics of the Unified Health System (DATASUS)/Ministry of Health. Results: There were 115,728 deaths from all causes, 69,757 in males. The annual mortality from cardiovascular diseases was 2.7/100,000 in men and 2.6/100,000 in women. The annual mortality from malformations of the circulatory system was 7.5/100,000 in men and 6.6/100,000 in women. Among the specific causes of circulatory diseases, cardiomyopathies had the highest rates of annual proportional mortality, and from malformations of the circulatory system, it occurred due to unspecified malformations of the circulatory system, at all ages and in both genders. Conclusion: Mortality from malformations of the circulatory system was most striking in the first years of life, while cardiovascular diseases were more relevant in adolescents. Low access to prenatal diagnosis or at birth probably prevented the proper treatment of malformations of the circulatory system.
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BACKGROUND AND PURPOSE: Accurate placement of an external ventricular drain (EVD) for the treatment of hydrocephalus is of paramount importance for its functionality and in order to minimize morbidity and complications. The aim of this study was to compare two different drain insertion assistance tools with the traditional free-hand anatomical landmark method, and to measure efficacy, safety and precision. METHODS: Ten cadaver heads were prepared by opening large bone windows centered on Kocher's points on both sides. Nineteen physicians, divided in two groups (trainees and board certified neurosurgeons) performed EVD insertions. The target for the ventricular drain tip was the ipsilateral foramen of Monro. Each participant inserted the external ventricular catheter in three different ways: 1) free-hand by anatomical landmarks, 2) neuronavigation-assisted (NN), and 3) XperCT-guided (XCT). The number of ventricular hits and dangerous trajectories; time to proceed; radiation exposure of patients and physicians; distance of the catheter tip to target and size of deviations projected in the orthogonal plans were measured and compared. RESULTS: Insertion using XCT increased the probability of ventricular puncture from 69.2 to 90.2 % (p = 0.02). Non-assisted placements were significantly less precise (catheter tip to target distance 14.3 ± 7.4 mm versus 9.6 ± 7.2 mm, p = 0.0003). The insertion time to proceed increased from 3.04 ± 2.06 min. to 7.3 ± 3.6 min. (p < 0.001). The X-ray exposure for XCT was 32.23 mSv, but could be reduced to 13.9 mSv if patients were initially imaged in the hybrid-operating suite. No supplementary radiation exposure is needed for NN if patients are imaged according to a navigation protocol initially. CONCLUSION: This ex vivo study demonstrates a significantly improved accuracy and safety using either NN or XCT-assisted methods. Therefore, efforts should be undertaken to implement these new technologies into daily clinical practice. However, the accuracy versus urgency of an EVD placement has to be balanced, as the image-guided insertion technique will implicate a longer preparation time due to a specific image acquisition and trajectory planning.
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Evidence concerning the presence or absence of common neuronglia lineages in the postnatal mammalian central nervous system is still a matter of speculation. We address this problem using optic nerve explants, which show an extremely long survival in culture. Morphological, immunocytochemical and immunochemical methods were applied. The results obtained from in vitro tissue were compared with optic nerves (ONs) and whole-brain samples from animals of different ages. Newborn rat ONs represented the starting material of our tissue culture; they are composed of unmyelinated axons, astrocytes and progenitor cells but devoid of neuronal cell bodies. At this age, Western blots of ONs were positively stained by neurofilament and synapsin I specific antibodies. These bands increased in intensity during postnatal in situ development. In explant cultures, the glia cells reach a stage of functional differentiation and they maintain, together with undifferentiated cells, a complex histotypic organization. After 6 days in vitro, neurofilaments and synapsin I could not be detected on immunoblots, indicating that 1) axonal degeneration was completed, and 2) neuronal somata were absent at the time. Surprisingly, after about 4-5 weeks in culture, a new cell type appeared, which showed characteristics typical of neurons. After 406 days in vitro, neurofilaments and synapsin I were unequivocally detectable on Western blots. Furthermore, both immunocytochemical staining and light and electron microscopic examinations corroborated the presence of this earlier-observed cell type. These in vitro results clearly show the high developmental plasticity of ON progenitor cells, even late in development. The existence of a common neuron-glia precursor, which never gives rise to neurons in situ, is suggested.
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Whether the somatosensory system, like its visual and auditory counterparts, is comprised of parallel functional pathways for processing identity and spatial attributes (so-called what and where pathways, respectively) has hitherto been studied in humans using neuropsychological and hemodynamic methods. Here, electrical neuroimaging of somatosensory evoked potentials (SEPs) identified the spatio-temporal mechanisms subserving vibrotactile processing during two types of blocks of trials. What blocks varied stimuli in their frequency (22.5 Hz vs. 110 Hz) independently of their location (left vs. right hand). Where blocks varied the same stimuli in their location independently of their frequency. In this way, there was a 2x2 within-subjects factorial design, counterbalancing the hand stimulated (left/right) and trial type (what/where). Responses to physically identical somatosensory stimuli differed within 200 ms post-stimulus onset, which is within the same timeframe we previously identified for audition (De Santis, L., Clarke, S., Murray, M.M., 2007. Automatic and intrinsic auditory "what" and "where" processing in humans revealed by electrical neuroimaging. Cereb Cortex 17, 9-17.). Initially (100-147 ms), responses to each hand were stronger to the what than where condition in a statistically indistinguishable network within the hemisphere contralateral to the stimulated hand, arguing against hemispheric specialization as the principal basis for somatosensory what and where pathways. Later (149-189 ms) responses differed topographically, indicative of the engagement of distinct configurations of brain networks. A common topography described responses to the where condition irrespective of the hand stimulated. By contrast, different topographies accounted for the what condition and also as a function of the hand stimulated. Parallel, functionally specialized pathways are observed across sensory systems and may be indicative of a computationally advantageous organization for processing spatial and identity information.
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INTRODUCTION: Timely diagnosis of invasive candidiasis (IC) remains difficult as the clinical presentation is not specific and blood cultures lack sensitivity and need a long incubation time. Thus, non-culture-based methods for diagnosing IC have been developed. Mannan antigen (Mn) and anti-mannan antibodies (A-Mn) are present in patients with IC. On behalf of the Third European Conference on Infections in Leukemia, the performance of these tests was analysed and reviewed. METHODS: The literature was searched for studies using the commercially available sandwich enzyme-linked immunosorbent assays (Platelia™, Bio-Rad Laboratories, Marnes-la-Coquette, France) for detecting Mn and A-Mn in serum. The target condition of this review was IC defined according to 2008 European Organization for Research and Treatment of Cancer/Mycoses Study Group criteria. Sensitivity, specificity and diagnostic odds ratios (DOR) were calculated for Mn, A-Mn and combined Mn/A-Mn testing. RESULTS: Overall, 14 studies that comprised 453 patients and 767 controls were reviewed. The patient populations included in the studies were mainly haematological and cancer cases in seven studies and mainly intensive care unit and surgery cases in the other seven studies. All studies but one were retrospective in design. Mn sensitivity was 58% (95% confidence interval [CI], 53-62); specificity, 93% (95% CI, 91-94) and DOR, 18 (95% CI 12-28). A-Mn sensitivity was 59% (95% CI, 54-65); specificity, 83% (95% CI, 79-97) and DOR, 12 (95% CI 7-21). Combined Mn/A-Mn sensitivity was 83% (95% CI, 79-87); specificity, 86% (95% CI, 82-90) and DOR, 58 (95% CI 27-122). Significant heterogeneity of the studies was detected. The sensitivity of both Mn and A-Mn varied for different Candida species, and it was the highest for C. albicans, followed by C. glabrata and C. tropicalis. In 73% of 45 patients with candidemia, at least one of the serological tests was positive before the culture results, with mean time advantage being 6 days for Mn and 7 days for A-Mn. In 21 patients with hepatosplenic IC, 18 (86%) had Mn or A-Mn positive test results at a median of 16 days before radiological detection of liver or spleen lesions. CONCLUSIONS: Mn and A-Mn are useful for diagnosis of IC. The performance of combined Mn/A-Mn testing is superior to either Mn or A-Mn testing.
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BACKGROUND: To date, there is no quality assurance program that correlates patient outcome to perfusion service provided during cardiopulmonary bypass (CPB). A score was devised, incorporating objective parameters that would reflect the likelihood to influence patient outcome. The purpose was to create a new method for evaluating the quality of care the perfusionist provides during CPB procedures and to deduce whether it predicts patient morbidity and mortality. METHODS: We analysed 295 consecutive elective patients. We chose 10 parameters: fluid balance, blood transfused, Hct, ACT, PaO2, PaCO2, pH, BE, potassium and CPB time. Distribution analysis was performed using the Shapiro-Wilcoxon test. This made up the PerfSCORE and we tried to find a correlation to mortality rate, patient stay in the ICU and length of mechanical ventilation. Univariate analysis (UA) using linear regression was established for each parameter. Statistical significance was established when p < 0.05. Multivariate analysis (MA) was performed with the same parameters. RESULTS: The mean age was 63.8 +/- 12.6 years with 70% males. There were 180 CABG, 88 valves, and 27 combined CABG/valve procedures. The PerfSCORE of 6.6 +/- 2.4 (0-20), mortality of 2.7% (8/295), CPB time 100 +/- 41 min (19-313), ICU stay 52 +/- 62 hrs (7-564) and mechanical ventilation of 10.5 +/- 14.8 hrs (0-564) was calculated. CPB time, fluid balance, PaO2, PerfSCORE and blood transfused were significantly correlated to mortality (UA, p < 0.05). Also, CPB time, blood transfused and PaO2 were parameters predicting mortality (MA, p < 0.01). Only pH was significantly correlated for predicting ICU stay (UA). Ultrafiltration (UF) and CPB time were significantly correlated (UA, p < 0.01) while UF (p < 0.05) was the only parameter predicting mechanical ventilation duration (MA). CONCLUSIONS: CPB time, blood transfused and PaO2 are independent risk factors of mortality. Fluid balance, blood transfusion, PaO2, PerfSCORE and CPB time are independent parameters for predicting morbidity. PerfSCORE is a quality of perfusion measure that objectively quantifies perfusion performance.
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The geodynamic forces acting in the Earth's interior manifest themselves in a variety of ways. Volcanoes are amongst the most impressive examples in this respect, but like with an iceberg, they only represent the tip of a more extensive system hidden underground. This system consists of a source region where melt forms and accumulates, feeder connections in which magma is transported towards the surface, and different reservoirs where it is stored before it eventually erupts to form a volcano. A magma represents a mixture of melt and crystals. The latter can be extracted from the source region, or form anywhere along the path towards their final crystallization place. They will retain information of the overall plumbing system. The host rocks of an intrusion, in contrast, provide information at the emplacement level. They record the effects of thermal and mechanical forces imposed by the magma. For a better understanding of the system, both parts - magmatic and metamorphic petrology - have to be integrated. I will demonstrate in my thesis that information from both is complementary. It is an iterative process, using constraints from one field to better constrain the other. Reading the history of the host rocks is not always straightforward. This is shown in chapter two, where a model for the formation of clustered garnets observed in the contact aureole is proposed. Fragments of garnets, older than the intrusive rocks are overgrown by garnet crystallizing due to the reheating during emplacement of the adjacent pluton. The formation of the clusters is therefore not a single event as generally assumed but the result of a two-stage process, namely the alteration of the old grains and the overgrowth and amalgamation of new garnet rims. This makes an important difference when applying petrological methods such as thermobarometry, geochronology or grain size distributions. The thermal conditions in the aureole are a strong function of the emplacement style of the pluton. therefore it is necessary to understand the pluton before drawing conclusions about its aureole. A study investigating the intrusive rocks by means of field, geochemical, geochronologi- cal and structural methods is presented in chapter three. This provided important information about the assembly of the intrusion, but also new insights on the nature of large, homogeneous plutons and the structure of the plumbing system in general. The incremental nature of the emplacement of the Western Adamello tonalité is documented, and the existence of an intermediate reservoir beneath homogeneous plutons is proposed. In chapter four it is demonstrated that information extracted from the host rock provides further constraints on the emplacement process of the intrusion. The temperatures obtain by combining field observations with phase petrology modeling are used together with thermal models to constrain the magmatic activity in the immediate intrusion. Instead of using the thermal models to control the petrology result, the inverse is done. The model parameters were changed until a match with the aureole temperatures was obtained. It is shown, that only a few combinations give a positive match and that temperature estimates from the aureole can constrain the frequency of ancient magmatic systems. In the fifth chapter, the Anisotropy of Magnetic Susceptibility of intrusive rocks is compared to 3D tomography. The obtained signal is a function of the shape and distribution of ferromagnetic grains, and is often used to infer flow directions of magma. It turns out that the signal is dominated by the shape of the magnetic crystals, and where they form tight clusters, also by their distribution. This is in good agreement with the predictions made in the theoretical and experimental literature. In the sixth chapter arguments for partial melting of host rock carbonates are presented. While at first very surprising, this is to be expected when considering the prior results from the intrusive study and experiments from the literature. Partial melting is documented by compelling microstructures, geochemical and structural data. The necessary conditions are far from extreme and this process might be more frequent than previously thought. The carbonate melt is highly mobile and can move along grain boundaries, infiltrating other rocks and ultimately alter the existing mineral assemblage. Finally, a mineralogical curiosity is presented in chapter seven. The mineral assemblage magne§site and calcite is in apparent equilibrium. It is well known that these two carbonates are not stable together in the system Ca0-Mg0-Fe0-C02. Indeed, magnesite and calcite should react to dolomite during metamorphism. The presented explanation for this '"forbidden" assemblage is, that a calcite melt infiltrated the magnesite bearing rock along grain boundaries and caused the peculiar microstructure. This is supported by isotopie disequilibrium between calcite and magnesite. A further implication of partially molten carbonates is, that the host rock drastically looses its strength so that its physical properties may be comparable to the ones of the intrusive rocks. This contrasting behavior of the host rock may ease the emplacement of the intrusion. We see that the circle closes and the iterative process of better constraining the emplacement could start again. - La Terre est en perpétuel mouvement et les forces tectoniques associées à ces mouvements se manifestent sous différentes formes. Les volcans en sont l'un des exemples les plus impressionnants, mais comme les icebergs, les laves émises en surfaces ne représentent que la pointe d'un vaste système caché dans les profondeurs. Ce système est constitué d'une région source, région où la roche source fond et produit le magma ; ce magma peut s'accumuler dans cette région source ou être transporté à travers différents conduits dans des réservoirs où le magma est stocké. Ce magma peut cristalliser in situ et produire des roches plutoniques ou alors être émis en surface. Un magma représente un mélange entre un liquide et des cristaux. Ces cristaux peuvent être extraits de la source ou se former tout au long du chemin jusqu'à l'endroit final de cristallisation. L'étude de ces cristaux peut ainsi donner des informations sur l'ensemble du système magmatique. Au contraire, les roches encaissantes fournissent des informations sur le niveau d'emplacement de l'intrusion. En effet ces roches enregistrent les effets thermiques et mécaniques imposés par le magma. Pour une meilleure compréhension du système, les deux parties, magmatique et métamorphique, doivent être intégrées. Cette thèse a pour but de montrer que les informations issues de l'étude des roches magmatiques et des roches encaissantes sont complémentaires. C'est un processus itératif qui utilise les contraintes d'un domaine pour améliorer la compréhension de l'autre. Comprendre l'histoire des roches encaissantes n'est pas toujours aisé. Ceci est démontré dans le chapitre deux, où un modèle de formation des grenats observés sous forme d'agrégats dans l'auréole de contact est proposé. Des fragments de grenats plus vieux que les roches intru- sives montrent une zone de surcroissance générée par l'apport thermique produit par la mise en place du pluton adjacent. La formation des agrégats de grenats n'est donc pas le résultat d'un seul événement, comme on le décrit habituellement, mais d'un processus en deux phases, soit l'altération de vieux grains engendrant une fracturation de ces grenats, puis la formation de zone de surcroissance autour de ces différents fragments expliquant la texture en agrégats observée. Cette interprétation en deux phases est importante, car elle engendre des différences notables lorsque l'on applique des méthodes pétrologiques comme la thermobarométrie, la géochronologie ou encore lorsque l'on étudie la distribution relative de la taille des grains. Les conditions thermales dans l'auréole de contact dépendent fortement du mode d'emplacement de l'intrusion et c'est pourquoi il est nécessaire de d'abord comprendre le pluton avant de faire des conclusions sur son auréole de contact. Une étude de terrain des roches intrusives ainsi qu'une étude géochimique, géochronologique et structurale est présente dans le troisième chapitre. Cette étude apporte des informations importantes sur la formation de l'intrusion mais également de nouvelles connaissances sur la nature de grands plutons homogènes et la structure de système magmatique en général. L'emplacement incrémental est mis en évidence et l'existence d'un réservoir intermédiaire en-dessous des plutons homogènes est proposé. Le quatrième chapitre de cette thèse illustre comment utiliser l'information extraite des roches encaissantes pour expliquer la mise en place de l'intrusion. Les températures obtenues par la combinaison des observations de terrain et l'assemblage métamorphique sont utilisées avec des modèles thermiques pour contraindre l'activité magmatique au contact directe de cette auréole. Au lieu d'utiliser le modèle thermique pour vérifier le résultat pétrologique, une approche inverse a été choisie. Les paramètres du modèle ont été changés jusqu'à ce qu'on obtienne une correspondance avec les températures observées dans l'auréole de contact. Ceci montre qu'il y a peu de combinaison qui peuvent expliquer les températures et qu'on peut contraindre la fréquence de l'activité magmatique d'un ancien système magmatique de cette manière. Dans le cinquième chapitre, les processus contrôlant l'anisotropie de la susceptibilité magnétique des roches intrusives sont expliqués à l'aide d'images de la distribution des minéraux dans les roches obtenues par tomographie 3D. Le signal associé à l'anisotropie de la susceptibilité magnétique est une fonction de la forme et de la distribution des grains ferromagnétiques. Ce signal est fréquemment utilisé pour déterminer la direction de mouvement d'un magma. En accord avec d'autres études de la littérature, les résultats montrent que le signal est dominé par la forme des cristaux magnétiques, ainsi que par la distribution des agglomérats de ces minéraux dans la roche. Dans le sixième chapitre, une étude associée à la fusion partielle de carbonates dans les roches encaissantes est présentée. Si la présence de liquides carbonatés dans les auréoles de contact a été proposée sur la base d'expériences de laboratoire, notre étude démontre clairement leur existence dans la nature. La fusion partielle est documentée par des microstructures caractéristiques pour la présence de liquides ainsi que par des données géochimiques et structurales. Les conditions nécessaires sont loin d'être extrêmes et ce processus pourrait être plus fréquent qu'attendu. Les liquides carbonatés sont très mobiles et peuvent circuler le long des limites de grain avant d'infiltrer d'autres roches en produisant une modification de leurs assemblages minéralogiques. Finalement, une curiosité minéralogique est présentée dans le chapitre sept. L'assemblage de minéraux de magnésite et de calcite en équilibre apparent est observé. Il est bien connu que ces deux carbonates ne sont pas stables ensemble dans le système CaO-MgO-FeO-CO.,. En effet, la magnésite et la calcite devraient réagir et produire de la dolomite pendant le métamorphisme. L'explication présentée pour cet assemblage à priori « interdit » est que un liquide carbonaté provenant des roches adjacentes infiltre cette roche et est responsable pour cette microstructure. Une autre implication associée à la présence de carbonates fondus est que la roche encaissante montre une diminution drastique de sa résistance et que les propriétés physiques de cette roche deviennent comparables à celles de la roche intrusive. Cette modification des propriétés rhéologiques des roches encaissantes peut faciliter la mise en place des roches intrusives. Ces différentes études démontrent bien le processus itératif utilisé et l'intérêt d'étudier aussi bien les roches intrusives que les roches encaissantes pour la compréhension des mécanismes de mise en place des magmas au sein de la croûte terrestre.
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Background: There is little information regarding the impact of diet on disease incidence and mortality in Switzerland. We assessed ecologic correlations between food availability and disease.Methods: In this ecologic study for the period 1970-2009, food availability was measured using the food balance sheets of the Food and Agriculture Organization of the United Nations. Standardized mortality rates (SMRs) were obtained from the Swiss Federal Office of Statistics. Cancer incidence data were obtained from the World Health Organization Health For All database and the Vaud Cancer Registry. Associations between food availability and mortality/incidence were assessed at lags 0, 5, 10, and 15 years by multivariate regression adjusted for total caloric intake.Results: Alcoholic beverages and fruit availability were positively associated, and fish availability was inversely associated, with SMRs for cardiovascular diseases. Animal products, meat, and animal fats were positively associated with the SMR for ischemic heart disease only. For cancer, the results of analysis using SMRs and incidence rates were contradictory. Alcoholic beverages and fruits were positively associated with SMRs for all cancer but inversely associated with all-cancer incidence rates. Similar findings were obtained for all other foods except vegetables, which were weakly inversely associated with SMRs and incidence rates. Use of a 15-year lag reversed the associations with animal and vegetal products, weakened the association with alcohol and fruits, and strengthened the association with fish.Conclusions: Ecologic associations between food availability and disease vary considerably on the basis of whether mortality or incidence rates are used in the analysis. Great care is thus necessary when interpreting our results.
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BACKGROUND: Life partnerships other than marriage are rarely studied in childhood cancer survivors (CCS). We aimed (1) to describe life partnership and marriage in CCS and compare them to life partnerships in siblings and the general population; and (2) to identify socio-demographic and cancer-related factors associated with life partnership and marriage. METHODS: As part of the Swiss Childhood Cancer Survivor Study (SCCSS), a questionnaire was sent to all CCS (aged 20-40 years) registered in the Swiss Childhood Cancer Registry (SCCR), aged <16 years at diagnosis, who had survived ≥ 5 years. The proportion with life partner or married was compared between CSS and siblings and participants in the Swiss Health Survey (SHS). Multivariable logistic regression was used to identify factors associated with life partnership or marriage. RESULTS: We included 1,096 CCS of the SCCSS, 500 siblings and 5,593 participants of the SHS. Fewer CCS (47%) than siblings (61%, P < 0.001) had life partners, and fewer CCS were married (16%) than among the SHS population (26%, P > 0.001). Older (OR = 1.14, P < 0.001) and female CCS (OR = 1.85, <0.001) were more likely to have life partners. CCS who had undergone radiotherapy, bone marrow transplants (global P Treatment = 0.018) or who had a CNS diagnosis (global P Diagnosis < 0.001) were less likely to have life partners. CONCLUSION: CCS are less likely to have life partners than their peers. Most CCS with a life partner were not married. Future research should focus on the effect of these disparities on the quality of life of CCS.
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Petrographic, mineralogical, and stable isotopes (delta C-13, delta O-18 values) compositions were used to characterise marbles and sedimentary carbonate rocks from central Morocco, which are considered to be a likely source of ornamental and building material from Roman time to the present day. This new data set was used in the frame of an archaeometric provenance study on Roman artefacts from the town of Thamusida (Kenitra, north Morocco), to assess the potential employment of these rocks for the manufacture of the archaeological materials. A representative set of samples from marbles and other carbonate rocks (limestone, dolostone) were collected in several quarries and outcrops in the Moroccan Meseta, in a region extending from the Meknes-Khenifra alignment to the Atlantic Ocean. All the samples were studied using a petrographic, mineralogical and geochemical methods. The petrographic and minerological investigations (optical microscopy, electron microscopy, X-ray diffraction) allowed to group the carbonate rocks in limestones, foliated limestone, diagenetic breccias and dolostone. The limestones could be further grouped as mudstones, wackestones-packstones, crinoid grainstones, oolitic grainstone and floatstones. Textural differences allowed to define marbles varieties. The stable carbon and oxygen isotope composition proved to be quite useful in the discrimination of marble sources, with apparently less discriminatory potential for carbonate rocks.