550 resultados para radon daughters


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Background: Lifetimes of nuclear excited states in fission fragments have been studied in the past following isotope separation, thus giving access mainly to the fragments' daughters and only to long-lived isomeric states in the primary fragments. For the first time now, short-lived excited states in the primary fragments, produced in neutron-induced prompt fission of U-235 and Pu-241, were studied within the EXILL&FATIMA campaign at the intense neutron-beam facility of the Institute Laue-Langevin in Grenoble. Purpose: We aim to investigate the quadrupole collective properties of neutron-rich even-even Xe-138,Xe-140,Xe-142 isotopes lying between the double shell closure N = 82 and Z = 50 and a deformed region with octupole collectivity. Method: The gamma rays emitted from the excited fragments were detected with a mixed array consisting of 8 HPGe EXOGAM Clover detectors (EXILL) and 16 LaBr3(Ce) fast scintillators (FATIMA). The detector system has the unique ability to select the interesting fragment making use of the high resolution of the HPGe detectors and determine subnanosecond lifetimes using the fast scintillators. For the analysis the generalized centroid difference method was used. Results: We show that quadrupole collectivity increases smoothly with increasing neutron number above the closed N = 82 neutron shell. Our measurements are complemented by state-of-the-art theory calculations based on shell-model descriptions. Conclusions: The observed smooth increase in quadrupole collectivity is similar to the evolution seen in the measured masses of the xenon isotopic chain and is well reproduced by theory. This behavior is in contrast to higher Z even-even nuclei where abrupt change in deformation occurs around N = 90.

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This article seeks to contribute to a more comprehensive understanding of the gender relations and the dowry system in India. It is based on a qualitative study that gave priority to the undertaking of interviews with women from different educational backgrounds living in the city of Hyderabad (South of India). The predominant perception of the interviewees is that education promotes economic and symbolic independence. The higher the educational level, the more critical accounts are found in relation to: the dowry system as a mechanism of reproduction of the low status of women and of the persistent asymmetries in gender relations; the wish to educate sons and daughters under equal conditions; and the value given to marriages based on love to the detriment of arranged ones. The main argument is that education is a fundamental source of women’s empowerment and opens up prospects for challenging the patriarchal regime, changing the status of women and leading to a more gender equal society. However, if this is to happen, then the education system (programs and curricula) needs to be congruent with gender equality, targeting both women and men in the project of challenging the dominant patriarchal structure.

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A comprehensive environmental monitoring program was conducted in the Ojo Guareña cave system (Spain), one of the longest cave systems in Europe, to assess the magnitude of the spatiotemporal changes in carbon dioxide gas (CO2) in the cave–soil–atmosphere profile. The key climate-driven processes involved in gas exchange, primarily gas diffusion and cave ventilation due to advective forces, were characterized. The spatial distributions of both processes were described through measurements of CO2 and its carbon isotopic signal (δ13C[CO2]) from exterior, soil and cave air samples analyzed by cavity ring-down spectroscopy (CRDS). The trigger mechanisms of air advection (temperature or air density differences or barometric imbalances) were controlled by continuous logging systems. Radon monitoring was also used to characterize the changing airflow that results in a predictable seasonal or daily pattern of CO2 concentrations and its carbon isotopic signal. Large daily oscillations of CO2 levels, ranging from 680 to 1900 ppm day−1 on average, were registered during the daily oscillations of the exterior air temperature around the cave air temperature. These daily variations in CO2 concentration were unobservable once the outside air temperature was continuously below the cave temperature and a prevailing advective-renewal of cave air was established, such that the daily-averaged concentrations of CO2 reached minimum values close to atmospheric background. The daily pulses of CO2 and other tracer gases such as radon (222Rn) were smoothed in the inner cave locations, where fluctuation of both gases was primarily correlated with medium-term changes in air pressure. A pooled analysis of these data provided evidence that atmospheric air that is inhaled into dynamically ventilated caves can then return to the lower troposphere as CO2-rich cave air.

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Background: Mutations of GDAP1 gene cause autosomal dominant and autosomal recessive Charcot-Marie-Tooth disease and more than 40 different mutations have been reported. The recessive Q163X mutation has been described in patients of Spanish ancestry, and a founder mutation in South American patients, originating in Spain has been demonstrated. Objective: We describe physical and histological features, and the molecular impact of mutation Q163X in a Colombian family. Methods: We report two female patients, daughters of consanguineous parents, with onset of symptoms within the first two years of life, developing severe functional impairment, without evidence of dysmorphic features, hoarseness or diaphragmatic paralysis. Electrophysiology tests showed a sensory and motor neuropathy with axonal pattern. Sequencing of GDAP1 gene was requested and the study identified a homozygous point mutation (c.487 C>T) in exon 4, resulting in a premature stop codon (p.Q163X). This result confirms the diagnosis of Charcot-Marie-Tooth disease, type 4A. Results: The patients were referred to Physical Medicine and Rehabilitation service, in order to be evaluated for ambulation assistance. They have been followed by Pulmonology service, for pulmonary function assessment and diaphragmatic paralysis evaluation. Genetic counseling was offered. The study of the genealogy of the patient, phenotypic features, and electrophysiological findings must be included as valuable tools in the clinical approach of the patient with Charcot-Marie-Tooth disease, in order to define a causative mutation. In patients of South American origin, the presence of GDAP1 gene mutations should be considered, especially the Q163X mutation, as the cause of CMT4A disease.

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Background: Mutations of GDAP1 gene cause autosomal dominant and autosomal recessive Charcot-Marie-Tooth disease and more than 40 different mutations have been reported. The recessive Q163X mutation has been described in patients of Spanish ancestry, and a founder mutation in South American patients, originating in Spain has been demonstrated. Objective: we describe physical and histological features, and the molecular impact of mutation Q163X in a Colombian family. Methods: We report two female patients, daughters of consanguineous parents, with onset of symptoms within the first two years of life, developing severe functional impairment, without evidence of dysmorphic features, hoarseness or diaphragmatic paralysis. Electrophysiology tests showed a sensory and motor neuropathy with axonal pattern. Sequencing of GDAP1 gene was requested and the study identified a homozygous point mutation (c.487 C>T) in exon 4, resulting in a premature stop codon (p.Q163X). This result confirms the diagnosis of Charcot-Marie-Tooth disease, type 4A. Results: The patients were referred to Physical Medicine and Rehabilitation service, in order to be evaluated for ambulation assistance. They have been followed by Pulmonology service, for pulmonary function assessment and diaphragmatic paralysis evaluation. Genetic counseling was offered. The study of the genealogy of the patient, phenotypic features, and electrophysiological findings must be included as valuable tools in the clinical approach of the patient with Charcot-Marie-Tooth disease, in order to define a causative mutation. In patients of South American origin, the presence of GDAP1 gene mutations should be considered, especially the Q163X mutation, as the cause of CMT4A disease.

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Ce mémoire porte sur la représentation des femmes de New Delhi et leurs perceptions d’elles-mêmes, comme filles et femmes dans la société indienne. Plus spécifiquement, les femmes rencontrées nous parlent de l’image des femmes en Inde, leur position et leur rôle dans la famille, en tant que filles, épouses et mères tout en étudiant leurs relations avec les autres (femmes et hommes). Dans l’objectif d’éclairer le phénomène de la sexo-sélection de l’enfant à naître et la discrimination basée sur le sexe, les rapports de genre pouvant être affectés par les pratiques et coutumes ont été analysés. Plus particulièrement, le discours et les expériences vécues des répondantes nous ont permis d’illustrer que les femmes rencontrées sont agentes de changement et qu’elles ont du pouvoir d’agir sur leurs vies.

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El interés de esta monografía es analizar las consecuencias de la representación institucional de India y Paquistán en la disputa territorial por Cachemira durante el periodo de 1989 a 2008. Puntualmente, se analiza y explica cómo la representación institucional prestada individualmente por India y Paquistán validó sus intereses como agentes de poder en la región, pasó por alto las necesidades de la población cachemir y fomentó la práctica de la desaparición forzada, lo que en consecuencia convirtió a las mujeres cachemires en un grupo subalterno. Para tal objetivo, se hará uso de la teoría postcolonialista, específicamente el enfoque subalternista de la autora Gayatri Chakravorty Spivak ya que permite explicar adecuadamente el proceso mediante el cual las mujeres cachemires se convirtieron en un grupo subalterno.

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When blood flows through small vessels, the two-phase nature of blood as a suspension of red cells (erythrocytes) in plasma cannot be neglected, and with decreasing vessel size, a homogeneous continuum model become less adequate in describing blood flow. Following the Haynes’ marginal zone theory, and viewing the flow as the result of concentric laminae of fluid moving axially, the present work provides models for fluid flow in dichotomous branching composed by larger and smaller vessels, respectively. Expressions for the branching sizes of parent and daughter vessels, that provides easier flow access, are obtained by means of a constrained optimization approach using the Lagrange multipliers. This study shows that when blood behaves as a Newtonian fluid, Hess – Murray law that states that the daughters-to-parent diameter ratio must equal to 2^(-1/3) is valid. However, when the nature of blood as a suspension becomes important, the expression for optimum branching diameters of vessels is dependent on the separation phase lengths. It is also shown that the same effect occurs for the relative lengths of daughters and parent vessels. For smaller vessels (e. g., arterioles and capillaries), it is found that the daughters-to-parent diameter ratio may varies from 0,741 to 0,849, and the daughters-to-parent length ratio varies from 0,260 to 2,42. For larger vessels (e. g., arteries), the daughters-to-parent diameter ratio and the daughters-to-parent length ratio range from 0,458 to 0,819, and from 0,100 to 6,27, respectively. In this paper, it is also demonstrated that the entropy generated when blood behaves as a single phase fluid (i. e., continuum viscous fluid) is greater than the entropy generated when the nature of blood as a suspension becomes important. Another important finding is that the manifestation of the particulate nature of blood in small vessels reduces entropy generation due to fluid friction, thereby maintaining the flow through dichotomous branching vessels at a relatively lower cost.

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La ricerca ricostruisce e analizza la storia della raccolta d’arte appartenuta al ramo senatorio della famiglia Malvezzi della Ca’ Grande all’interno del variegato panorama collezionistico bolognese settecentesco. La volontà di indagarne lo sviluppo è motivata sia dalla sua esemplarità che dal suo carattere eccezionale. Fondata da Piriteo III (1658-1728) con l’acquisto e la commissione di una cinquantina di dipinti, sia di artisti contemporanei sia di maestri antichi, a cui si aggiungono le opere ereditate dagli antenati, la raccolta fu accresciuta nell’arco di sole tre generazioni. Il principale artefice dell’ampliamento del patrimonio pittorico del casato fu il figlio Sigismondo III (1703-1787), tramite il quale confluì nella quadreria anche l’importante collezione del marchese Paolo Magnani, suo zio materno. Compiendo scelte collezionistiche originali rispetto a quelle d’ordine marcatamente municipalistico, Sigismondo raccolse per la galleria della Ca’ Grande numerose opere di artisti stranieri, glorificati e ricercati in campo europeo, ma estranei di norma al gusto petroniano dell’epoca. Al marchese spetta, inoltre, l’acquisizione del celebre nucleo di opere tre-quattrocentesche, che andò a formare la Camera degli Antichi. Secondo principi illuministici, questi mirava a possedere una sorta di ideale museo privato, ove fosse possibile ammirare il progresso dell’arte petroniana dalle origini sino alla modernità e istituire paragoni fra le più importanti scuole pittoriche. Anche l’erede Piriteo IV (1734-1806) continuò ad ampliare la collezione, compiendo acquisti più limitati, ma non per questo meno significativi. Alla sua morte si estinse la linea maschile del ramo senatorio, per cui la prestigiosa quadreria fu divisa tra le figlie Maria (1780-1865) e Teresa (1782-1811). La raccolta Malvezzi non ebbe la fortuna di confluire entro collezioni durature, cosicché in cinquant’anni quella che fu una delle più importanti gallerie della Bologna settecentesca è stata irrimediabilmente dispersa.

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Il tema centrale di questa Tesi è il cosiddetto "Teorema di Rappresentazione di Riesz" per i funzionali positivi su alcuni spazi di funzione continue. Questo Teorema, caposaldo dell'Analisi Funzionale, è inscindibilmente legato alla Teoria della Misura. Esso, infatti, stabilisce un'importante legame tra funzionali lineari positivi e misure positive di Radon. Dopo un'ampia disamina di questo Teorema, la Tesi si concentra su alcune delle sue Applicazioni in Analisi Reale e in Teoria del Potenziale. Nello specifico, viene provato un notevole risultato di Analisi Reale: la differenziabilità quasi dappertutto delle funzioni monotone su un intervallo reale. Nella dimostrazione di questo fatto, risulta cruciale anche un interessantissimo argomento di "continuità dalla positività", attraverso cui passiamo varie volte nella Tesi. Infatti, esso è determinante anche nelle Applicazioni in Teoria del Potenziale per la costruzione della misura armonica di un aperto regolare e della cosiddetta "misura di Riesz di una funzione subarmonica".