904 resultados para Drop
Resumo:
The Cretaceous Mont Saint-Hilaire complex (Quebec, Canada) comprises three major rock units that were emplaced in the following sequence: (I) gabbros; (II) diorites; (III) diverse partly agpaitic foid syenites. The major element compositions of the rock-forming minerals, age-corrected Nd and oxygen isotope data for mineral separates and trace element data of Fe-Mg silicates from the various lithologies imply a common source for all units. The distribution of the rare earth elements in clinopyroxene from the gabbros indicates an ocean island basalt type composition for the parental magma. Gabbros record temperatures of 1200 to 800 degrees C, variable silica activities between 0 center dot 7 and 0 center dot 3, and f(O2) values between -0 center dot 5 and +0 center dot 7 (log delta FMQ, where FMQ is fayalite-magnetite-quartz). The diorites crystallized under uniform a(SiO2) (a(SiO2) = 0 center dot 4-0 center dot 5) and more reduced f(O2) conditions (log delta FMQ similar to-1) between similar to 1100 and similar to 800 degrees C. Phase equilibria in various foid syenites indicate that silica activities decrease from 0 center dot 6-0 center dot 3 at similar to 1000 degrees C to < 0 center dot 3 at similar to 550 degrees C. Release of an aqueous fluid during the transition to the hydrothermal stage caused a(SiO2) to drop to very low values, which results from reduced SiO(2) solubilities in aqueous fluids compared with silicate melts. During the hydrothermal stage, high water activities stabilized zeolite-group minerals. Fluid inclusions record a complex post-magmatic history, which includes trapping of an aqueous fluid that unmixed from the restitic foid syenitic magma. Cogenetic aqueous and carbonic fluid inclusions reflect heterogeneous trapping of coexisting immiscible external fluids in the latest evolutionary stage. The O and C isotope characteristics of fluid-inclusion hosted CO(2) and late-stage carbonates imply that the surrounding limestones were the source of the external fluids. The mineral-rich syenitic rocks at Mont Saint-Hilaire evolved as follows: first, alkalis, high field strength and large ion lithophile elements were pre-enriched in the (late) magmatic and subsequent hydrothermal stages; second, percolation of external fluids in equilibrium with the carbonate host-rocks and mixing processes with internal fluids as well as fluid-rock interaction governed dissolution of pre-existing minerals, element transport and precipitation of mineral assemblages determined by locally variable parameters. It is this hydrothermal interplay between internal and external fluids that is responsible for the mineral wealth found at Mont Saint-Hilaire.
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Education plays a very important role in society’s development in order to promote good citizenship and individual rights and freedom. To this end, it is fundamental that girls be included in the education process. Inmost developed and developing countries, theoretically, both males and females have access to education. Cape Verde is no exception; however, the reality is that even in Cape Verde, promoting girls’ education and creating conditions to motivate girls to stay in school remains a challenge. Whereas girls have access to education many girls drop out for gender-related reasons. This paper will investigate girls’ education initiatives in general, and Cape Verde specific to offer recommendations and strategies to keep girls in school.
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Most stereotypes about Africans and their descendants started with colonialism in the fifteenth century. The encounter between Africans and Europeans facilitated the creation of myths and stereotypes about the colonized peoples, which were made effective through the naturalization of differences. The relationship between skin color and slavery developed to produce a racialized system of forced labor on which colonialism depended for its survival. Stereotypes functioned to legitimize colonial authority by building the notion that the colonizer ruled over the colonized because of an innate superiority. Therefore, stereotyping is an effective "discursive strategy" (Bhabha) based on fixity and repetition with the aim of controlling the other. Harriet Beecher Stowe’s Uncle Tom’s Cabin and José Evaristo D’Almeida O Escravo both denounced the evils of slavery in the United States of America and Cape Verde respectively, claiming for the end of the institution. However, they are both ambivalent towards slaves and blacks, being unable to envisage social equality for the two races. Both authors construct their black characters as stereotypical others, but they depict the light-skin characters as superior both culturally and physically. The bi-racial characters are portrayed as the ones who possess beauty and intelligence as an inheritance from their European ancestry, while blacks are relegated to the margins. We need to consider, however, that slavery in Cape Verde had different characteristics from its counterpart in the United States of America. In Cape Verde the Africans outnumbered the Europeans and that circumstance favored miscegenation and the emergence of forms of mixed culture, which came to be seen as positive and natural. In the United States of America miscegenation was regarded as a taboo since early. And even after Emancipation, “the one-drop rule” made the offspring of an African descendant black, however 'white' he or she might be.
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Acute myocardial dysfunction is a typical manifestation of septic shock. Experimentally, the administration of endotoxin [lipopolysacharride (LPS)] to laboratory animals is frequently used to study such dysfunction. However, a majority of studies used load-dependent indexes of cardiac function [including ejection fraction (EF) and maximal systolic pressure increment (dP/dt(max))], which do not directly explore cardiac inotropism. Therefore, we evaluated the direct effects of LPS on myocardial contractility, using left ventricular (LV) pressure-volume catheters in mice. Male BALB/c mice received an intraperitoneal injection of E. coli LPS (1, 5, 10, or 20 mg/kg). After 2, 6, or 20 h, cardiac function was analyzed in anesthetized, mechanically ventilated mice. All doses of LPS induced a significant drop in LV stroke volume and a trend toward reduced cardiac output after 6 h. Concomitantly, there was a significant decrease of LV preload (LV end-diastolic volume), with no apparent change in LV afterload (evaluated by effective arterial elastance and systemic vascular resistance). Load-dependent indexes of LV function were markedly reduced at 6 h, including EF, stroke work, and dP/dt(max). In contrast, there was no reduction of load-independent indexes of LV contractility, including end-systolic elastance (ejection phase measure of contractility) and the ratio dP/dt(max)/end-diastolic volume (isovolumic phase measure of contractility), the latter showing instead a significant increase after 6 h. All changes were transient, returning to baseline values after 20 h. Therefore, the alterations of cardiac function induced by LPS are entirely due to altered loading conditions, but not to reduced contractility, which may instead be slightly increased.
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A análise do ADN baseada nos STRs (Short Tandem Repeats) tem provado ser uma ferramenta extremamente útil em estudos forenses. A aplicação dos multiplex de STRs resulta em perfis genéticos completos, para a maior parte das amostras, desde que contenham uma quantidade apreciável de ADN. Contudo, em amostras com ADN degradado, a análise tornase mais complicada, uma vez que os STRs com maior peso molecular (acima dos 250 pb), podem não ser amplificados nestas condições. Como a metodologia de Mini-STRs não estava, ainda, implementada nos Laboratórios Forenses portugueses, o objectivo principal deste estudo consistiu na aplicação de um multiplex, designado por Mini-SGM, que contém os marcadores TH01, FGA, D18S51, D16S359, D2S1338 e a Amelogenina, para implementação na prática forense, tendo os resultados sido comparados com a metodologia de rotina. O trabalho experimental teve início com um estudo populacional, que compreendeu uma amostra de 110 indivíduos de origem portuguesa, não relacionados e uma amostra de 52 indivíduos, não relacionados, oriundos de Cabo Verde, encontrando-se, ambas as populações, em Equilíbrio de Hardy-Weinberg, excepto para o locus D18S51, na população portuguesa e o locus D2S1338 na população de origem africana. Em relação aos parâmetros estatísticos forenses, este estudo demonstrou que o poder de discriminação varia entre 0,903 e 0,959, para a população portuguesa, e entre 0,908 e 0,958, para a população de Cabo Verde. Após o estudo populacional, foram analisados 39 casos forenses, devidamente anonimizados, da casuística do Serviço de Genética e Biologia Forense da Delegação de Lisboa do INML, com diferentes tipos de vestígios biológicos, como sangue, ossos, pulmão, coração, tecidos embrionários, tecidos inclusos em parafina, fígado, rim e dentes, de modo a ilustrar a utilidade desta nova metodologia nos casos forenses. No estudo de amostras degradadas, o uso da metodologia de rotina pode,
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This paper documents that at the individual stock level insiders sales peak many months before a large drop in the stock price, while insiders purchases peak only the month before a large jump. We provide a theoretical explanation for this phenomenon based on trading constraints and asymmetric information. We test our hypothesis against competing stories such as patterns of insider trading driven by earnings announcement dates, or insiders timing their trades to evade prosecution. Finally we provide new evidence regarding crashes and the degree of information asymmetry.
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We propose an alternative method for measuring intergenerational mobility. Measurements obtained fromtraditional methods (based on panel data) are scarce, difficult to compare across countries and almost impossible to get across time. In particular, this means that we do not know how intergenerational mobility is correlated with growth, income or the degree of inequality.Our proposal is to measure the informative content of surnames in one census. The more information thesurname has on the income of an individual, the more important is her background in determining her outcomes; and thus, the less mobility there is.The reason is that surnames provide information about family relationships because the distribution ofsurnames is necessarily very skewed. A large percentage of the population is bound to have a very unfrequent surname. For them the partition generated by surnames is very informative on family linkages.First, we develop a model whose endogenous variable is the joint distribution of surnames and income.There, we explore the relationship between mobility and the informative content of surnames. We allow for assortative mating to be a determinant of both.Second, we use our methodology to show that in large Spanish region the informative content of surnamesis large and consistent with the model. We also show that it has increased over time, indicating a substantial drop in the degree of mobility. Finally, using the peculiarities of the Spanish surname convention we show that the degree of assortative mating has also increased over time, in such a manner that might explain the decrease in mobility observed.Our method allows us to provide measures of mobility comparable across time. It should also allow us tostudy other issues related to inheritance.
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BACKGROUND: Antiretroviral therapy (ART) decreases morbidity and mortality in HIV-infected patients but is associated with considerable adverse events (AEs). METHODS: We examined the effect of AEs to ART on mortality, treatment modifications and drop-out in the Swiss HIV Cohort Study. A cross-sectional evaluation of prevalence of 13 clinical and 11 laboratory parameters was performed in 1999 in 1,078 patients on ART. AEs were defined as abnormalities probably or certainly related to ART. A score including the number and severity of AEs was defined. The subsequent progression to death, drop-out and treatment modification due to intolerance were evaluated according to the baseline AE score and characteristics of individual AEs. RESULTS: Of the 1,078 patients, laboratory AEs were reported in 23% and clinical AEs in 45%. During a median follow up of 5.9 years, laboratory AEs were associated with higher mortality with an adjusted hazard ratio (HR) of 1.3 (95% confidence interval [CI] 1.2-1.5; P < 0.001) per score point. For clinical AEs no significant association with increased mortality was found. In contrast, an increasing score for clinical AEs (HR 1.11,95% CI 1.04-1.18; P = 0.002), but not for laboratory AEs (HR 1.07, 95% CI 0.97-1.17; P = 0.17), was associated with antiretroviral treatment modification. AEs were not associated with a higher drop-out rate. CONCLUSIONS: The burden of laboratory AEs to antiretroviral drugs is associated with a higher mortality. Physicians seem to change treatments to relieve clinical symptoms, while accepting laboratory AEs. Minimizing laboratory drug toxicity seems warranted and its influence on survival should be further evaluated.
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Stable isotopes of carbonates (delta(13)C(carb), delta(18)O(carb)), organic matter (delta(13)C(org), delta(15)N(org)) and major, trace and rare earth element (REE) compositions of marine carbonate rocks of Late Permian to Early Triassic age were used to establish the position of the Permian-Triassic boundary (PTB) at two continuous sections in the Velebit Mountain, Croatia. The chosen sections - Rizvanusa and Brezimenjaca - are composed of two lithostratigraphic units, the Upper Permian Transitional Dolomite and the overlying Sandy Dolomite. The contact between these units, characterized by the erosional features and sudden occurrence of ooids and siliciclastic grains, was previously considered as the chronostratigraphic PTB. The Sandy Dolomite is characterized by high content of non-carbonate material (up to similar to 30 wt.% insoluble residue), originated from erosion of the uplifted hinterland. A relatively rich assemblage of Permian fossils (including Geinitzina, Globivalvulina, Hemigordius, bioclasts of gastropods, ostracods and brachiopods) was found for the first time in Sandy Dolomite, 5 m above the lithologic boundary in the Rizvanusa section. A rather abrupt negative delta(13)C(carb) excursion in both sections appears in rocks showing no recognizable facies change within the Sandy Dolomite, -2 parts per thousand at Rizvanusa and -1.2 parts per thousand at Brezimenjaca, 11 m and 0.2 m above the lithologic contact, respectively. This level within the lower part of the Sandy Dolomite is proposed as the chemostratigraphic PTB. In the Rizvanusa section, the delta(13)C(org) values decline gradually from similar to-25 parts per thousand in the Upper Permian to similar to-29 parts per thousand in the Lower Triassic. The first negative delta(13)C(org) excursion occurs above the lithologic contact, within the uppermost Permian deposits, and appears to be related to the input of terrigenous material. The release of isotopically light microbial soil-biomass into the shallow-marine water may explain this sudden decrease of delta(13)C(org) values below the PTB. This would support the hypothesis that in the western Tethyan realm the land extinction, triggering a sudden drop of woody vegetation and related land erosion, preceded the marine extinction. The relatively low delta(15)N(org) values at the Permian-Triassic (P-Tr) transition level, close to approximate to 0 parts per thousand, and a secondary negative delta(13)C(org) excursion of -0.5 parts per thousand point to significant terrestrial input and primary contribution of cyanobacteria. The profiles of the concentrations of redox-sensitive elements (Ce, Mn, Fe, V), biogenic or biogenic-scavenged elements (P, Ba, Zn, V), Ce/Ce* values, and normalized trace elements, including Ba/Al, Ba/Fe, Ti/Al, Al/(Al + Fe + Mn) and Mn/Ti show clear excursions at the Transitional Dolomite-Sandy Dolomite lithologic boundary and the chemostratigraphic P-Tr boundary. The stratigraphic variations indicate a major regression phase marking the lithologic boundary, transgressive phases in the latest Permian and a gradual change into shallow/stagnant anoxic marine environment towards the P-Tr boundary level and during the earliest Triassic. (C) 2010 Elsevier B.V. All rights reserved.
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Purpose: Aqueous shunt implantation into the anterior chamber is associated with corneal decompensation in up to a third of eyes. Intracameral tube position may affect corneal endothelial cell loss. The authors set out to examine the efficacy and safety of Baerveldt shunt implantation into the ciliary sulcus combined with surgical peripheral iridectomy (SPI). Methods: One hundred eyes prospectively underwent Baerveldt shunt implantation into the cilliary sulcus combined with SPI, leaving a short intracameral tube length (1-2mm). Pre and post operative measures recorded included patient demographics, visual acuity, IOP, number of glaucoma medications (GMs) and all complications. Pre-existing corneal decompensation was recorded. Success was defined as IOP≤21mmHg and 20% reduction in IOP from baseline with or without GMs. Results: Mean age was 65.4 years (±20.4years). Mean follow-up was 10.8 months. Preoperatively IOP was 25.7mmHg (± 9.9mmHg), GMs were 2.9 (±1.2) and VA was 0.4 (±0.3). At one year postoperatively there was a significant drop in IOP (mean= 13.3mmHg (± 5.0mmHg); p<0.001) and number of GMs (mean= 1.3 (±1.4); p<0.001); and no significant change in VA (mean= 0.4 (±0.3); p=0.93). The success rate at one year was 83%. Complications were minor and non sight threatening (10%), there were no cases of postoperative corneal decompensation, tube blockage or iris/corneal-tube contact. Conclusions: The results demonstrate that placement of Baerveldt shunts into the ciliary sulcus with SPI is a safe and efficacious method of IOP reduction in comparison with standard shunt positioning in the anterior chamber. The intracameral tube position combined with SPI avoided tube-iris contact and corneal decompensation. Sulcus placement of aqueous shunts should be considered in pseudophakic eyes.
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PURPOSE: To report a series of patients with cerebellar dysfunction and altered vision during motion, and to quantify their visual impairment in motion with a simple clinical test. METHODS: Twenty consecutive patients suffering from cerebellar dysfunction and altered vision during motion were examined between 1994 and 2007. A control group consisted of 20 age- and sex-matched healthy people. All patients had a full neuro-ophthalmic examination. Near visual acuity (NVA) was measured at rest (static NVA) and during chair rotation (dynamic NVA). Distance visual acuity (DVA) was measured at rest (static DVA) and during rotation of the patient's head (dynamic DVA). RESULTS: Only four of the 20 patients reported altered vision during motion spontaneously. The remaining 16 patients admitted this unusual visual disturbance only when asked specifically. All patients exhibited abnormal eye movements, including saccadic smooth pursuit (20/20), dysmetric saccades (15/20), nystagmus (19/20) and impaired suppression of vestibulo-ocular reflex (VOR) (20/20). During rotation of the examination chair (dynamic NVA), the drop in NVA averaged 5.6 lines (range 1-10 lines). During rotation of the patient's head (dynamic DVA), the drop in DVA averaged only 2.5 lines (range 0-10 lines). For the control group, there was no significant drop in NVA under dynamic conditions. CONCLUSION: Patients with cerebellar dysfunction rarely complain spontaneously of altered vision during motion. However, specific questioning may bring up this unusual symptom. The use of a simple clinical test, consisting of NVA measurement during rotation of the examination chair (dynamic NVA), allows practitioners to quantify the level of visual impairment in patients presenting altered VOR modulation.
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Se evaluó la utilización de la malla de 50 mm (2”) en redes de cerco artesanal de la Región Tumbes en una pesquería multiespecífica. Se trabajó con una red control de tamaño de malla de 38 mm (1,5”) y la red experimental de 50 mm (2,0”), con un porcentaje de embande de 0,65 y 0,77, respectivamente. Se determinó diferencia entre las curvas de profundidad de calado del cuerpo central de las redes (tc= 46,670, t*= 1,98, p= 0) la red experimental tuvo mayor profundidad de velado; entre las curvas de velocidad de caída del cuerpo central de las redes, hubo diferencia significativa (tc= 7,790, t*= 1,98, p = 0,000), debido al mayor lastre y filtrado de las mallas de la red experimental. El coeficiente abertura horizontal (μ1) de las mallas en la franja superior durante el máximo velado de la red y el gareteo fue en las mallas del cabecero o copo, parte central y ultimo cuerpo de la red, en promedio 0,71; 0,74 y 0,73 respectivamente; (valores cercanos al coeficiente de armado ideal para el escape de ciertos peces fusiformes). El promedio de μ1 obtenidos en la región de las mallas centrales en el cabecero, centro y ultimo cuerpo de la red fue 0,85; 0,85 y 0,84 respectivamente; lo que indicó una mayor abertura horizontal de las mallas por encima del valor del coeficiente de armado que no permitiría el escape de los peces. Se concluyó que por la condición de las mallas de la red de cerco experimental (tamaño de malla 50 mm) no es óptima para gran parte de la estructura de la red, esto no permitiría la selectividad por tamaños.
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Background Multiple sclerosis (MS) is a demyelinating disease of the central nervous system, which mainly affects young adults. In Finland, approximately 2500 out of 6000 MS patients have relapsing MS and are treated with disease modifying drugs (DMD): interferon- β (INF-β-1a or INF-β-1b) and glatiramer acetate (GA). Depending on the used IFN-β preparation, 2 % to 40 % of patients develop neutralizing antibodies (NAbs), which abolish the biological effects of IFN-β, leading to reduced clinical and MRI detected efficacy. According to the Finnish Current Care Guidelines and European Federation of Neurological Societis (EFNS) guidelines, it is suggested tomeasure the presence of NAbs during the first 24 months of IFN-β therapy. Aims The aim of this thesis was to measure the bioactivity of IFN-β therapy by focusing on the induction of MxA protein (myxovirus resistance protein A) and its correlation to neutralizing antibodies (NAb). A new MxA EIA assay was set up to offer an easier and rapid method for MxA protein detection in clinical practice. In addition, the tolerability and safety of GA were evaluated in patients who haddiscontinued IFN-β therapy due to side effects and lack of efficacy. Results NAbs developed towards the end of 12 months of treatment, and binding antibodies were detectable before or parallel with them. The titer of NAb correlated negatively with the amount of MxA protein and the mean values of preinjection MxA levels never returned to true baseline in NAb negative patients, but tended to drop in the NAb positive group. The test results between MxA EIA and flow cytometric analysis showed significant correlation. GA reduced the relapse rate and was a safe and well-tolerated therapy in IFN-β-intolerant MS patients. Conclusions NAbs inhibit the induction of MxA protein, which can be used as a surrogate marker of the bioactivity of IFN-β therapy. Compared to flow cytometricanalysis and NAb assay, MxA-EIA seemed to be a sensitive and more practical method in clinical use to measure the actual bioactivity of IFN-β treatment, which is of value also from a cost-effective perspective.
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Generic substitution of antiepileptic drugs (EAD) have limited use because epilepsy is a chronic disease, seizure recurrence has an important impact of the quality of life and the potential risk of accidents. EADs have a narrow therapeutic window, non negligible side effects and complex interactions. Bioavailability of generic EADs, tested in healthy men during a limited period of time must be within the 90% IC, in which means that serum levels can range from 80% to 125% of the original drug. A slight drop in serum level could increase the risk of seizure recurrence, as indicated by several publications. Although no formal studies regarding cost effectiveness and the rate of seizure recurrence is available yet, the prevailing consensus recommends not to replace an original antiepileptic drug by a generic, due to the harmful risk of seizure recurrence.
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OBJECTIVE: Although intracranial hypertension is one of the important prognostic factors after head injury, increased intracranial pressure (ICP) may also be observed in patients with favourable outcome. We have studied whether the value of ICP monitoring can be augmented by indices describing cerebrovascular pressure-reactivity and pressure-volume compensatory reserve derived from ICP and arterial blood pressure (ABP) waveforms. METHOD: 96 patients with intracranial hypertension were studied retrospectively: 57 with fatal outcome and 39 with favourable outcome. ABP and ICP waveforms were recorded. Indices of cerebrovascular reactivity (PRx) and cerebrospinal compensatory reserve (RAP) were calculated as moving correlation coefficients between slow waves of ABP and ICP, and between slow waves of ICP pulse amplitude and mean ICP, respectively. The magnitude of 'slow waves' was derived using ICP low-pass spectral filtration. RESULTS: The most significant difference was found in the magnitude of slow waves that was persistently higher in patients with a favourable outcome (p<0.00004). In patients who died ICP was significantly higher (p<0.0001) and cerebrovascular pressure-reactivity (described by PRx) was compromised (p<0.024). In the same patients, pressure-volume compensatory reserve showed a gradual deterioration over time with a sudden drop of RAP when ICP started to rise, suggesting an overlapping disruption of the vasomotor response. CONCLUSION: Indices derived from ICP waveform analysis can be helpful for the interpretation of progressive intracranial hypertension in patients after brain trauma.