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Abstract  

The original purpose of this investigation started in 1996 was to study the radiological impact on the local population of the village of Chichiviriche de La Costa. But, soon after the major earthquake (Ms=6.8) in the state of Sucre on July 9, 1997, the objective was changed to study the fluctuation of radon (222Rn) to see if it could be correlated to seismic activity and/or if the amonlous change just before the earthquake can be considered a precusor for it. Measurements of222Rn by simply de-gassing about 250 ml of natural thermal water employing a Pylon AB-5 radiation monitor and counting the radiation after it reached equilibrium were performed. The values for four sampling periods in the first half of 1996 were about 17 Bq/l of222Rn, a month before the earthquake they were less than 15 Bq/l and increased about 70% to 25 Bq/l two days before the seismic event. In about two weeks, they returned to about 18 Bq/l. But, surprisingly, they have gradually increased to about 35 Bq/l, before leveling off at about 27 Bq/l.

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Changes of volatile compounds of noni juice during the traditional process of fermentation/aging was studied by means of HS-SPME and GC-MS. Major acids, octanoic and hexanoic, diminished their concentration; while esters of ethanol, 1-butanol and 1-hexanol, with their flavour fruity notes, increased. The concentration of esters of methanol and 3-methyl-3-buten-1-ol decreased during the fermentation/aging process, whereas major alcohols of noni juice, 1-hexanol and 1-octanol, increased their concentration during the process. During the 60 days of the process the volatile composition of the noni juice had reached stability. These chemical changes justify that fermented juice possesses a flavour less pungent than fresh juice due to an important decrease in the hexanoic and octanoic contents, as well as a greater fruity note due to the increment in ester concentrations.

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In 2005, a severe drought occurred in Portugal, with several reservoirs becoming dry in the southern region. A set of 20 Portuguese water bodies were analysed through denaturing gradient gel electrophoresis (16SrDNA-DGGE) and DNA sequencing to assess its bacterioplankton diversity under these particular conditions. Environmental parameters were determined to assess the trophic conditions of each water body. Most water bodies fell into the meso-to eutrophic and hypereutrophic state. In general, the levels for conductivity, pH and total suspended solids were higher than the average data from previous years. Dominant phylotypes belonged to Cyanobacteria, Actinobacteria Alphaproteobacteria, Betaproteobacteria and Bacteroidetes groups. Despite the geographic distance, common phylotypes could be recorded among water bodies. Bacteroidetes dominated at Sousa River and were related to high nutrient levels. Cyanobacteria dominated at Alentejo reservoirs and correlated with higher conductivity values. However, Actinobacteria showed ubiquitous phylotypes throughout several samples, suggesting its persistence over geographically distant water bodies. This study showed a clear deterioration of water quality, from a physico-chemical point of view; furthermore, dominance of Cyanobacteria and Actinobacteria in reservoirs used for drinking water supply were also detected, which may become a concerning issue. However, the most severe bacterial community composition variations between summer 2005 and others were mainly related to higher water residence times. Thus, along with the expected intensification of drought episodes, with severe effects particularly in Southern Europe, it is clearly predictable an intensification in risks for water quality maintenance and even Public Health.

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Abstract

Background and aims

Compulsive Sexual Behavior Disorder (CSBD) is characterized by a persistent failure to control intense and recurrent sexual impulses, urges, and/or thoughts, resulting in repetitive sexual behavior that causes a marked impairment in important areas of functioning. Despite its recent inclusion in the forthcoming ICD-11, concerns regarding its assessment, diagnosis, prevalence or clinical characteristics remain. The purpose of this study was to identify participants displaying CSBD through a novel data-driven approach in two independent samples and outline their sociodemographic, sexual, and clinical profile.

Methods

Sample 1 included 1,581 university students (females = 56.9%; M age = 20.58) whereas sample 2 comprised 1,318 community members (females = 43.6%; M age = 32.37). First, we developed a new composite index to assess the whole range of CSBD symptoms based on three previously validated scales. Based on this new composite index, we subsequently identified individuals with CSBD through a cluster analytic approach.

Results

The estimated occurrence of CSBD was 10.12% in sample 1 and 7.81% in sample 2. Participants with CSBD were mostly heterosexual males, younger than respondents without CSBD, reported higher levels of sexual sensation seeking and erotophilia, an increased offline and especially online sexual activity, more depressive and anxious symptoms, and poorer self-esteem.

Conclusions

This research provides further evidence on the occurrence of CSBD based on an alternative data-driven approach, as well as a detailed and nuanced description of the sociodemographic, sexual, and clinical profile of adults with this condition. Clinical implications derived from these findings are discussed in detail.

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Abstract  

The concentrations of40K,226Ra,232Th and137Cs were determined in the upper layers of soils in the central coastal region of Venezuela. The activities of137Cs are higher in the areas where the forest is well developed, oriented towards the wind and at higher elevations. The origin of the137Cs deposition is from water input from the clouds directly in the cloudforest and rainfall from the northeast trade winds. Even though the values of137Cs are much higher in these areas, there is little or no significant increase in the health risk. The natural radioactivity is correlated with the geology in the region except in the area of Urama. The values for the natural radiation background are as follows: for potassium between 1–3%, for radium between 1–3 ppm and for thorium the range was 6–39 ppm. The corresponding amounts of absorbed dose rates in air, the exposure rates and the annual effective dose equivalents are in the following ranges respectively: 11–39 pGy/s, 4–16 uR/h and 0.25–0.86 mSv/y. The annual effective dose equivalents include the contribution of the global average (2.57 mSv/y) of the rest of the natural sources of radiation. Finally, the largest natural radioactivity background, was found near Chichiriviche as a result of the massive granite deposits in this area, but again there is no significant health risk.

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Journal of Thermal Analysis and Calorimetry
Authors: M. I. Yoshida, M. A. Oliveira, E. C. L. Gomes, W. N. Mussel, W. V. Castro, and C. D. V. Soares

Abstract

Thermogravimetry (TG) and differential scanning calorimetry (DSC) are useful techniques that have been successfully applied in the pharmaceutical industry to reveal important information regarding the physicochemical properties of drug and excipient molecules such as polymorphism, stability, purity, and formulation compatibility among others. In this study, lovastatin was studied by TG, DSC, and other techniques such as Fourier transform infrared spectroscopy, optical microscopy, X-ray diffraction, chromatography, and mass spectrometry. Lovastatin showed melting point at 445 K and thermal stability up to 535 K. It presented morphological polymorphism, which in the drug has the same unit cell, but with different crystal habits. Preservative excipient butylhydroxyanisole (BHA) causes amorphization of lovastatin crystallites and, therefore is incompatible with lovastatin. Degradation by hydrolysis was observed under neutral, acid, and basic conditions. The active degradation product, lovastatin hydroxyacid, was obtained after neutral and basic hydrolysis.

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Journal of Thermal Analysis and Calorimetry
Authors: Késia K. V. Castro, Ana A. D. Paulino, Edjane F. B. Silva, Thiago Chellappa, Maria B. D. L. Lago, Valter J. Fernandes Jr., and Antonio S. Araujo

Abstract

Thermogravimetry (TG) was used in this study to evaluate thermal and catalytic pyrolysis of Atmospheric Petroleum Residue (ATR) which can be found in the state of Rio Grande do Norte/Brazil, after a process of atmospheric distillation of petroleum. The utilized sample in the process of catalytic pyrolysis was Al-MCM-41, a mesoporous material. The procedures for obtaining the thermogravimetric curves were performed in a thermobalance with heating rates of 5, 10, and 20 °C min−1. From TG, the activation energy was determined using the Flynn–Wall kinetic method, which decreased from 161 kJ mol−1, for the pure ATR, to 71 kJ mol−1, in the presence of the Al-MCM-41, showing the efficiency of the catalyst in the pyrolysis of Atmospheric Petroleum Residue.

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