964 resultados para Gautier, Théophile, 1811-1872


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O uso de probióticos na alimentação dos peixes pode estimular o sistema imunológico e agir na prevenção de enfermidades. O presente estudo avaliou a fisiologia de pirarucu Arapaima gigas após alimentação por 30 dias com dietas enriquecidas com probiótico Bacillus subtilis em 3 níveis de inclusão: 0 (Controle); 0,02 (BS0,02%) e 0,05% (BS0,05%) (triplicata), sendo realizada biometria e coleta de amostras de sangue. Os grupos foram comparados entre si (P<0,05). O peso, comprimento e o índice hepatossomático (IHS) dos pirarucus BS0,05% foram menores que os do Controle. As análises hematológicas e bioquímicas indicaram que BS0,02% promoveu aumento do hematócrito e da albumina, com relação aos demais grupos; e diminuição da concentração de hemoglobina corpuscular média (CHCM) e da glicose plasmática com relação ao Controle. A hemoglobina corpuscular média (HCM) e atividade respiratória dos leucócitos do BS0,05% diminuíram com relação ao Controle. BS0,02% apresentaram redução do número de leucócitos, com relação ao Controle, que refletiu na diminuição de monócitos, neutrófilos, LG-PAS e eosinófilos. Assim, os níveis de B. subtilis avaliados não promoveram crescimento ou alterações fisiológicas nos pirarucus, que indiquem melhoria do seu sistema imune.

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IntroducciónHace poco, un colega historiador, me hizo llegar una copia de una carta que su tutor de estudios en Barcelona, a su vez, pusiera en sus manos. La carta en cuestión es una de esas curiosidades histográficas que, en el trayecto de la labor de archivo, a veces, se tiene suerte de encontrar. en ocaciones, tales hallazgos pueden conducir a trabajos de excepcional importancia, como sucedió a Carlos Guinzburg en una comunidad.

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The interaction of quercetin, which is a bioflavonoid, with bovine serum albumin (BSA) was investigated under pseudo-physiological conditions by the application of UV–vis spectrometry, spectrofluorimetry and cyclic voltammetry (CV). These studies indicated a cooperative interaction between the quercetin–BSA complex and warfarin, which produced a ternary complex, quercetin–BSA–warfarin. It was found that both quercetin and warfarin were located in site I. However, the spectra of these three components overlapped and the chemometrics method – multivariate curve resolution-alternating least squares (MCR-ALS) was applied to resolve the spectra. The resolved spectra of quercetin–BSA and warfarin agreed well with their measured spectra, and importantly, the spectrum of the quercetin–BSA–warfarin complex was extracted. These results allowed the rationalization of the behaviour of the overlapping spectra. At lower concentrations ([warfarin] < 1 × 10−5 mol L−1), most of the site marker reacted with the quercetin–BSA, but free warfarin was present at higher concentrations. Interestingly, the ratio between quercetin–BSA and warfarin was found to be 1:2, suggesting a quercetin–BSA–(warfarin)2 complex, and the estimated equilibrium constant was 1.4 × 1011 M−2. The results suggest that at low concentrations, warfarin binds at the high-affinity sites (HAS), while low-affinity binding sites (LAS) are occupied at higher concentrations.

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Single-strand DNA (ssDNA)-binding proteins (SSBs) are ubiquitous and essential for a wide variety of DNA metabolic processes, including DNA replication, recombination, DNA damage detection and repair1. SSBs have multiple roles in binding and sequestering ssDNA, detecting DNA damage, stimulating nucleases, helicases and strand-exchange proteins, activating transcription and mediating protein–protein interactions. In eukaryotes, the major SSB, replication protein A (RPA), is a heterotrimer1. Here we describe a second human SSB (hSSB1), with a domain organization closer to the archaeal SSB than to RPA. Ataxia telangiectasia mutated (ATM) kinase phosphorylates hSSB1 in response to DNA double-strand breaks (DSBs). This phosphorylation event is required for DNA damage-induced stabilization of hSSB1. Upon induction of DNA damage, hSSB1 accumulates in the nucleus and forms distinct foci independent of cell-cycle phase. These foci co-localize with other known repair proteins. In contrast to RPA, hSSB1 does not localize to replication foci in S-phase cells and hSSB1 deficiency does not influence S-phase progression. Depletion of hSSB1 abrogates the cellular response to DSBs, including activation of ATM and phosphorylation of ATM targets after ionizing radiation. Cells deficient in hSSB1 exhibit increased radiosensitivity, defective checkpoint activation and enhanced genomic instability coupled with a diminished capacity for DNA repair. These findings establish that hSSB1 influences diverse endpoints in the cellular DNA damage response.

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Honing and Ladinig (2008) make the assertion that while the internal validity of web-based studies may be reduced, this is offset by an increase in external validity possible when experimenters can sample a wider range of participants and experimental settings. In this paper, the issue of internal validity is more closely examined, and it is agued that there is no necessary reason why internal validity of a web-based study should be worse than that of a lab-based one. Errors of measurement or inconsistencies of manipulation will typically balance across conditions of the experiment, and thus need not necessarily threaten the validity of a study’s findings.

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A whole-genome scan was conducted to map quantitative trait loci (QTL) for BSE resistance or susceptibility. Cows from four half-sib families were included and 173 microsatellite markers were used to construct a 2835-cM (Kosambi) linkage map covering 29 autosomes and the pseudoautosomal region of the sex chromosome. Interval mapping by linear regression was applied and extended to a multiple-QTL analysis approach that used identified QTL on other chromosomes as cofactors to increase mapping power. In the multiple-QTL analysis, two genome-wide significant QTL (BTA17 and X/Y ps) and four genome-wide suggestive QTL (BTA1, 6, 13, and 19) were revealed. The QTL identified here using linkage analysis do not overlap with regions previously identified using TDT analysis. One factor that may explain the disparity between the results is that a more extensive data set was used in the present study. Furthermore, methodological differences between TDT and linkage analyses may affect the power of these approaches.

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A large literature shows that violence against women in intimate relationships varies across racial/ethnic groups. However, it is unclear whether such variations differ across urban, suburban, and rural areas. The main objective of this article is to examine this issue using 1992 to 2009 National Crime Victimization Survey data. We also test the hypothesis that racial/ethnic minority women living in rural areas are more likely to be assaulted by their current and former intimate partners than are their urban and suburban counterparts. Contrary to expectations, results indicated virtually no differences in the rates at which urban, suburban, and rural racial/ethnic minority females were victims of intimate violence. The results indicate the great need of additional research into this important topic.

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This article is based on research we conducted in two agricultural communities as part of a broader study that included mining communities in rural Australia. The data from the agricultural locations tell a different story to that of the mining communities. In the latter, alcohol-fuelled, male-on-male assaults in public places caused considerable anxiety among informants. By contrast, people in the agricultural communities seemed more troubled by hidden violent harms which were largely privatised and individualised, including self-harm, suicide, isolation and threats to men’s general wellbeing and mental health; domestic violence; and other forms of violence largely unreported and thus unacknowledged within the wider community (including sexual assault and bullying linked to homophobia). We argue one reason for the different pattern in the agricultural communities is the decline of pub(lic) masculinity, and with this, the increasing isolation of rural men and the increasing propensity to internalise violence. We argue that the relatively high rates of suicide in agricultural communities experiencing rural decline are symptomatic of the internalisation of violence.

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Background and aims: The assessment of intra-epidermal nerve fiber density (IENFD) in skin biopsies and corneal nerve fiber density (CNFD) using corneal confocal microscopy (CCM) provides promising techniques to detect small nerve fiber damage in patients with peripheral neuropathy. To help define the clinical utility of each of these techniques in patients with diabetic neuropathy we have assessed sensitivity and specificity of IENFD and CNFD in predicting the following: 1) diabetic polyneuropathy (DPN); 2) risk of foot ulceration (RFU); 3) initial small fiber neuropathy (iSFN); 4) severe small fiber neuropathy (sSFN)...

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The Brain Research Institute (BRI) uses various types of indirect measurements, including EEG and fMRI, to understand and assess brain activity and function. As well as the recovery of generic information about brain function, research also focuses on the utilisation of such data and understanding to study the initiation, dynamics, spread and suppression of epileptic seizures. To assist with the future focussing of this aspect of their research, the BRI asked the MISG 2010 participants to examine how the available EEG and fMRI data and current knowledge about epilepsy should be analysed and interpreted to yield an enhanced understanding about brain activity occurring before, at commencement of, during, and after a seizure. Though the deliberations of the study group were wide ranging in terms of the related matters considered and discussed, considerable progress was made with the following three aspects. (1) The science behind brain activity investigations depends crucially on the quality of the analysis and interpretation of, as well as the recovery of information from, EEG and fMRI measurements. A number of specific methodologies were discussed and formalised, including independent component analysis, principal component analysis, profile monitoring and change point analysis (hidden Markov modelling, time series analysis, discontinuity identification). (2) Even though EEG measurements accurately and very sensitively record the onset of an epileptic event or seizure, they are, from the perspective of understanding the internal initiation and localisation, of limited utility. They only record neuronal activity in the cortical (surface layer) neurons of the brain, which is a direct reflection of the type of electrical activity they have been designed to record. Because fMRI records, through the monitoring of blood flow activity, the location of localised brain activity within the brain, the possibility of combining fMRI measurements with EEG, as a joint inversion activity, was discussed and examined in detail. (3) A major goal for the BRI is to improve understanding about ``when'' (at what time) an epileptic seizure actually commenced before it is identified on an eeg recording, ``where'' the source of this initiation is located in the brain, and ``what'' is the initiator. Because of the general agreement in the literature that, in one way or another, epileptic events and seizures represent abnormal synchronisations of localised and/or global brain activity the modelling of synchronisations was examined in some detail. References C. M. Michel, G. Thut, S. Morand, A. Khateb, A. J. Pegna, R. Grave de Peralta, S. Gonzalez, M. Seeck and T. Landis, Electric source imaging of human brain functions, Brain Res. 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Toth, Spatial relationship between neuronal activity and bold functional mri, NeuroImage , 21 (3), 2004, 876--885. doi:10.1016/j.neuroimage.2003.10.018 A. Connelly, G. D. Jackson, R. S. Frackowiak, J. W. Belliveau, F. Vargha-Khadem and D. G. Gadian, Functional mapping of activated human primary cortex with a clinical mr imaging system, Radiology , 188 (1), 1993, 125--130. L. Allison, Hidden Markov Models, Technical Report , School of Computer and Software Engineering, Monash University, 2000. R. J. Elliott, L. Aggoun and J.B. Moore, Hidden Markov Models: Estimation and Control, Appl. Math.-Czech. , 2004. B. Bhavnagri, Discontinuities of plane functions projected from a surface with methods for finding these , Technical Report, 2009. B. Bhavnagri, Computer Vision using Shape Spaces , Technical Report,1996, University of Adelaide. B. 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Recent developments in analytical technologies have driven significant advances in lipid science. The sensitivity and selectivity of modern mass spectrometers can now provide for the detection and even quantification of many hundreds of lipids in a single analysis. In parallel, increasing evidence from structural biology suggests that a detailed knowledge of lipid molecular structure including carbon-carbon double bond position, stereochemistry and acyl chain regiochemistry is required to fully appreciate the biochemical role(s) of individual lipids. Here we review the capabilities and limitations of tandem mass spectrometry to provide this level of structural specificity in the analysis of lipids present in complex biological extracts. In particular, we focus on the capabilities of a novel technology termed ozone-induced dissociation to identify the position (s) of double bonds in unsaturated lipids and discuss its possible role in efforts to develop workflows that provide for complete structure elucidation of lipids by mass spectrometry alone: so-called top-down lipidomics. This article is part of a Special Issue entitled: Lipodomics and Imaging Mass Spectrom. (C) 2011 Elsevier B.V. All rights reserved.

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Wi-Fi is a commonly available source of localization information in urban environments but is challenging to integrate into conventional mapping architectures. Current state of the art probabilistic Wi-Fi SLAM algorithms are limited by spatial resolution and an inability to remove the accumulation of rotational error, inherent limitations of the Wi-Fi architecture. In this paper we leverage the low quality sensory requirements and coarse metric properties of RatSLAM to localize using Wi-Fi fingerprints. To further improve performance, we present a novel sensor fusion technique that integrates camera and Wi-Fi to improve localization specificity, and use compass sensor data to remove orientation drift. We evaluate the algorithms in diverse real world indoor and outdoor environments, including an office floor, university campus and a visually aliased circular building loop. The algorithms produce topologically correct maps that are superior to those produced using only a single sensor modality.

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PURPOSE To determine the prevalence of refractive errors in Shiraz schoolchildren by age and gender. METHODS For this cross-sectional study, random cluster sampling was carried out from students of the 2008-2009 academic year. After the initial interview, ophthalmic examinations including tests of visual acuity, non-cycloplegic and cycloplegic refraction and binocular vision were performed. Myopia was defined as a spherical equivalent < or =-0.50 dioptre (D), hyperopia as > or =+2.0 D, and astigmatism as a cylinder refraction > or =0.75 D. All values for school grade and gender were directly standardized based on the total student population in the 2008-2009 school year. RESULTS A total of 2130 students were sampled, of which 1872 participated in the study (response rate = 87.88%). The prevalence of uncorrected, best-corrected, presenting and spectacle corrected visual acuity of 6/12 or worse in the better eye was 6.46%, 0%, 1.49% and 0.9%, respectively. The prevalence rates of myopia, hyperopia and astigmatism were 4.35% (95% confidence interval [CI]: 2.89-5.82%), 5.04% (95% CI: 3.50-6.58%), and 11.27% (95% CI: 9.81-12.74%), respectively. Anisometropia was detected in 2.58% of schoolchildren. The prevalence of hyperopia significantly decreased with age (P = 0.021). CONCLUSIONS Compared with other reported rates, the prevalence of myopia in the schoolchildren of Shiraz is similar to that in most places excluding East Asian countries, and that of hyperopia is in the mid range.

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Purpose: To determine the prevalence and risk factors of refractive errors among schoolchildren in Shiraz, Iran. Methods: In a cross-sectional study, using random cluster sampling, 3065 Shiraz schoolchildren were selected in this study. The participants totaled 2683; 1872 elementary and middle school and 811 high school students. For the primary and middle schoolchildren, cycloplegic refraction and for the high school students, non-cycloplegic autorefraction was measured. Myopia, defined as spherical equivalent (SE) refraction -0.50 diopter (D) or worse, hyperopia as SE +2.00D and +0.50D or more for cycloplegic and noncycloplegic refractions respectively, and astigmatism as cylinder -0.75D or worse. Results: The prevalence of refractive errors in elementary and middle school students was: myopia 4.35 % (95% confidence interval (CI), 2.89 -5.81), hyperopia 5.04 % (95%CI, 3.49 -6.58) and astigmatism 11.79 % (95%CI, 10.21 -13.38). For high school students, these rates were 22.4 % (95%CI, 18.44 -26.36), 10.52 % (95%CI, 6.75 -14.29) and 20.99% (95%CI, 16.55 -25.44), respectively.The prevalence of myopia increased with age in primary and middle school students (OR=1.15, 95% CI, 0.98 to1.33, p=0.073). Conclusions: The result of this study indicated a relatively low prevalence of refractive errors among schoolchildren in Shiraz according to the protocol by "Refractive Error Study in Children" (RESC) in other investigations.

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Finnish scholarship students in Russia during the autonomy (1812-1917) During the autonomy in Finland (1809-1917), an attempt to improve the knowledge of the Russian language was made through special language university scholarships. With these scholarships the students could go and study the Russian language and acquire cultural knowledge in Russia. Other member countries on the edges of the Russian Empire, like Poland and the Baltic provinces, did not have similar programs. The first two scholars started their journey in 1812. A system of travel allowances was introduced in 1841. Between the years 1812- 1917 a total of almost 400 students studied in Russia. The studies mainly took place in Moscow. These scholarship students were called the Master s of Moscow ". In this paper, Finnish-Russian relations are studied based on the attitude towards the Russian language and the people who studied it in Finland. Although the attitude towards them was neutral in the beginning, in 1844 there was a strong change. Students of Russian, and especially the scholars, received the stigma of being unreliable and unpatriotic, a stigma they were never able to get rid of. The study of the Russian language was voluntary in Finnish schools between 1863 and 1872. Starting from 1890, however, the study of the Russian language was enforced. In doing so, the Russians attempted to unify the Empire, while the Finns had the illusion that they had their own state. Thus, Russia saw the language as a way to unify the Empire and Finns as an attempt to make them Russians. The purpose of studying in Russia was to improve the student s practical language skills and overall knowledge of the customs and culture of the country. Besides knowing the language, knowledge of Russian culture and customs is essential in understanding Russia and Russians; therefore, the studies of literature, geography and history have been noted in this research. Without knowledge it is difficult to develop understanding. After their studies, almost all of the scholars returned to Finland and did not continue their careers in Russia. They worked mainly as teachers and civil servants, and managed to improve the Finnish people s weak knowledge of Russian and Russia through teaching, translations of literature and newspaper articles. Through these scholars, it is possible to see how the attitudes towards the language have been closely related to the political history between Finland and Russia. The language became the subject of resistance and these attitudes were transferred to its students. In 1917, the study of Russia and the Russian language ended and it was no longer possible to use the acquired knowledge of language and country in independent Finland.