Coulomb and nuclear excitations of narrow resonances in Ne-17

New experimental data for dissociation of relativistic 17Ne projectiles incident on targets of lead, carbon, and polyethylene targets at GSI are presented. Special attention is paid to the excitation and decay of narrow resonant states in 17Ne. Distributions of internal energy in the O15+p+p three-body system have been determined together with angular and partial-energy correlations between the decay products in different energy regions. The analysis was done using existing experimental data on 17Ne and its mirror nucleus 17N. The isobaric multiplet mass equation is used for assignment of observed resonances and their spins and parities. A combination of data from the heavy and light targets yielded cross sections and transition probabilities for the Coulomb excitations of the narrow resonant states. The resulting transition probabilities provide information relevant for a better understanding of the 17Ne structure

Quasifree (p, 2p) Reactions on Oxygen Isotopes: Observation of Isospin Independence of the Reduced Single-Particle Strength

Quasifree one-proton knockout reactions have been employed in inverse kinematics for a systematic study of the structure of stable and exotic oxygen isotopes at the R3B/LAND setup with incident beam energies in the range of 300-450 MeV/u. The oxygen isotopic chain offers a large variation of separation energies that allows for a quantitative understanding of single-particle strength with changing isospin asymmetry. Quasifree knockout reactions provide a complementary approach to intermediate-energy one-nucleon removal reactions. Inclusive cross sections for quasifree knockout reactions of the type OA(p,2p)NA-1 have been determined and compared to calculations based on the eikonal reaction theory. The reduction factors for the single-particle strength with respect to the independent-particle model were obtained and compared to state-of-the-art ab initio predictions. The results do not show any significant dependence on proton-neutron asymmetry

Feeding behaviour and digestion physiology in larval fish – current knowledge and gaps and bottlenecks in research

Food uptake follows rules defined by feeding behaviour that determines the kind and quantity of food ingested by fish larvae as well as how live prey and food particles are detected, captured and ingested. Feeding success depends on the progressive development of anatomical characteristics and physiological functions and on the availability of suitable food items throughout larval development. The fish larval stages present eco-morpho-physiological features very different from adults and differ from one species to another. The organoleptic properties, dimensions, detectability, movements characteristics and buoyancy of food items are all crucial features that should be considered, but is often ignored, in feeding regimes. Ontogenetic changes in digestive function lead to limitations in the ability to process certain feedstuffs. There is still a lack of knowledge about the digestion and absorption of various nutrients and about the ontogeny of basic physiological mechanisms in fish larvae, including how they are affected by genetic, dietary and environmental factors. The neural and hormonal regulation of the digestive process and of appetite is critical for optimizing digestion. These processes are still poorly described in fish larvae and attempts to develop optimal feeding regimes are often still on a ‘trial and error’ basis. A holistic understanding of feeding ecology and digestive functions is important for designing diets for fish larvae and the adaptation of rearing conditions to meet requirements for the best presentation of prey and microdiets, and their optimal ingestion, digestion and absorption. More research that targets gaps in our knowledge should advance larval rearing

Streptococcus mutans en saliva y su relación con caries dental. En una población infantil de la comunidad de Tacoaleche Guadalupe, Zacatecas

La caries dental es frecuente en humanos, la valoración del Strep- tococcus mutans es importante para el desarrollo de la caries. La actividad de caries está re- lacionada con la prevalencia de Streptococcus mutans en saliva. El objetivo del estudio fue relacionar Strep- tococcus mutans en saliva y caries en niños de Tacoaleche, Zacatecas. Se estudiaron 139 niños de 6-13 años de edad. Se determinó el ceo/CPOD, IHOS y UFC/ml de Streptococcus mutans, el coeficiente de variación Ð= 93%, se determinó riesgo a caries con concentración de ufc/ml de S. mutans y la experiencia relati- va de caries. La prevalencia de caries fue del 67.6%, el promedio de ceo/CPOD fue de 2.4 y de IHOS 1.25, el 71.9% presentó riesgo bajo, 10.8% alto y 15.82% moderado, la experiencia de caries relativa el 51.79% fue baja, 32.37% resistente, 10.79% alto y 5.03% rampante. Hubo correspondencia entre los niveles de Streptococcus mutans y el CPOD. (150)La caries dental es una de las enfermedades infecciosas más frecuentes en humanos, la valoración de la composición de la flora mi- crobiana es importante para el desarrollo de la caries dental y así como la disposición de nutrientes, el Streptococcus mutans aprove- cha la presencia de carbohidratos producien- do ácido y la subsecuente desmineralización del esmalte. Estas especies son consideradas como los principales agentes causales de la caries y su presencia es valorada como un factor importante de riesgo junto con la ex- periencia de caries y la dieta entre otros. Una actividad de caries alta está relacionada con un incremento en la prevalencia de Strepto- coccus mutans en saliva. El objetivo de este estudio fue determinar la presencia de Strep- tococcus mutans en saliva y su relación con caries dental en una población infantil de la comunidad de Tacoaleche Guadalupe, Zaca-tecas. Se estudiaron 139 niños con edades de 6-13 años. Se determino el ceo/CPOD, IHOS y UFC/ml de Streptococcus mutans. Se de- terminó el coeficiente de variación Ð inter e intragrupal con una Ð= 93%, se recolectaron muestras de saliva y se realizaron diluciones seriadas para posteriormente realizar cultivos en agar mitis salivarius y determinar el riesgo a caries de acuerdo con la concentración de ufc/ml de S. mutans y la experiencia relativa de caries, se encontró una prevalencia de ca- ries dental del 67.6 %, se encontró un valor medio de ceo/CPOD de 2.4 y de IHOS 1.25, el 71.9% bajo presenta un riesgo, 10.8% alto y solo 15.82 % moderado, en contraste con la experiencia de caries relativa el 51.79 % tie- ne una experiencia baja, 32.37% resistente, 10.79% alto y 5.03% rampante.Se detectó una correspondencia entre los niveles de Strepto- coccus mutans y el CPOD

Fluoride Concentration in Saliva and Dental Caries Relation in Children from Fluorosis Endemic Area.

It was proved the association between fluoride ingestion and dental low prevalence of dental caries experience. Objetive: To study the association between the caries experience, severity of fluorosis and sa- liva concentration of fluoride in rural area. Material and methods: A descriptive, Trans- versal and quantitative study was performed. It was registered the dmft/DMFT, caries ex- perience, fluorosis index, plaque index and fluoride concentration determination using potentiometric ion specific method in saliva, drinking water and from the water supply were performed. Data was analyze by Kruskal Wal- lis and varianza analysis.Se ha demostrado asociación entre la ingesta de fluoruro y disminución en la experiencia de caries.Objetivo: Establecer la relación de la expe- riencia de caries, la severidad de fluorosis y la concentración de fluoruro en saliva, en una población infantil rural. Materiales y métodos. Estudio descriptivo, transversal y cuantitativo. Se registró el ceo y CPOD, la experiencia de caries, índice de fluo- rosis, prevalencia y severidad, concentración de fluoruros en saliva y agua de consumo por métodos incrementales en potenciometría de Ión específico. Se realizó análisis de varianza y la prueba de Kruskal Wallis

Niveles de Streptococcus mutans y prevalencia de caries dental en una población de escolares de la zona urbana de la ciudad de Zacatecas

The oral health level and the role of Streptococcus mutans and dental plaque accumulation in the development of dental caries are important factors for the analysis and determination of importance as a risk factors, it have been demonstrated in preschool and scholars children, deficient hygiene practices, and for these reasons is important to use microbiological proce- dures in order to evaluate quantitative and qualitative the dental plaque conditions. The aim of this work is to determine the prevalence of dental caries in a group of school children from 10- 13 years old from the urban area in Zacatecas City and determinate the presence of S. mutans in saliva in order to establish a relation between DMFT and the amount of S. mutans. It was determined the DMFT and the SOHI as well as the ufcs/mL of S. mutans in 150 children of both sex in a school of urban area in Zacatecas City, we found a 56% prevalence of dental caries and a correspondence between the S. mutans levels and the DMFT index; for this reason is important to control the amount of S. mutans in dental plaque.El estado de salud bucal, el papel que juega el Streptococcus mutans y la acumulación de placa dental en el desarrollo de caries son factores importantes de análisis, para determinar la importancia que tienen como factores de riesgo. Se ha demostrado que los niños en edades de preescolar y de educación primaria no tienen buenos hábitos de higiene, de igual forma es importante la utilización de procedimientos microbiológicos que permitan evaluar en forma cuantitativa y cualitativa las condiciones de la placa dental. El objetivo de este estudio es determinar la prevalencia de caries dental en un grupo de estudiantes de educa- ción primaria de 10-13 años de la zona urbana de la ciudad de Zacatecas y determinar la presencia y cantidad de S. mutans en saliva para establecer una correspondencia con el CPOD. Se determinó el IHOS, CPOD y el ufc/mL de S. mutans a 150 niños de ambos sexos de una escuela primaria de la zona urbana de la ciudad de Zacatecas y se encontró una prevalencia de caries dental del 56%, así mismo se detectó una correspondencia entre los niveles de S. mutans y el CPOD por lo que es importante establecer mecanismos de control en la proliferación de este microorganismo

PRESENCE OF NITRATES AND NITRITES IN WATER FOR HUMAN CONSUMPTION AND THEIR IMPACT ON PUBLIC HEALTH IN SUGARCANE-PRODUCING AREAS

Water pollution has emerged as a consequence of human settlements, as well as from specific rural, agricultural, forestry and industrial activities within a region. It has been found that increasing use of nitrogen fertilizers also increases water pollution. Nitrates and nitrites that are dissolved in groundwater used for human consumption cause adverse health effects, such as production of nitrosamines (cause of cancer) and decrease of oxygen carrying capacity of the blood, known as blue baby syndrome. The aim of this study was to determine the relationship between the concentration of dissolved nitrates and nitrites in drinking water, and the incidence of esophagus and stomach cancer in the population living close to agricultural areas. The maximum concentration of nitrates (NO3-) in water for human consumption was 7.5 mg L-1. A total of 45 cases of esophagus and stomach cancer were identified, distributed in six agricultural municipalities studied. A weak correlation (r = 0.46, p < 0.05) was found between the factor of rational use of nitrogen in sugarcane cultivation and the number of cancer cases recorded in the area of study