Determination of a critical stress and distance criterion for crack propagation in cutting models of cheese

A critical stress at a critical distance crack propagation criterion is a good way to model the fracture in cheese. This physical criterion states that the crack-tip node debonds when the stress at a specified distance ahead of the crack tip on the assumed crack path reaches a critical value. Although this criterion is already used in other research domains, no consistent information exists on how the critical stress and distance should be determined. A repeatable method for the determination of this criterion which combines experimental and numerical single edge notched bending tests was acquired. This criterion was validated with wire cutting experiments of cheese. The experimental and numerical results showed the same trend with a clear wire indentation and steady state cutting phase. The determination of a critical stress and distance criterion as proposed in this research is a good approach to model fracture and cutting of cheese

Developments in understanding and assessment of egg and egg product quality over the last century

The hen's egg, in the form of table eggs and egg products, forms a staple part of the world's total protein consumption. In the last century, there has been considerable research effort focusing on ways of improving egg production and enhancing the quality of eggs. More recently, and with the development and application of new molecular technologies, our understanding and knowledge of how an egg is formed, what it actually consists of, in terms of its major versus minor components, and what the functional roles of each of these components might be, have been greatly enhanced. For example, new previously unknown molecules with specific activity or functional properties have been discovered in the egg albumen and yolk, some of which have potential uses in pharmaceutical and other food related applications. This review paper, which is the collaborative effort of members of Working Group 4 - Quality of Eggs and Egg Products - of the European Federation of WPSA, describes the scientific research behind a number of these major advances and provides some insight to the focus of current research in this area

Automatic Identification of Defects on Eggshell Through a Multispectral Vision System

The objective of this research was to develop an off-line artificial vision system to automatically detect defective eggshells, i.e., dirty or cracked eggshells, by employing multispectral images with the final purpose to adapt the system to an on-line grading machine. In particular, this work was focused to study the feasibility of identifying organic stains on brown eggshells (dirty eggshell), caused by blood, feathers, feces, etc., from natural stains, caused by deposits of pigments on the outer layer of clean eggshells. During the analysis a total of 384 eggs were evaluated (clean: 148, dirty: 236). Dirty samples were evaluated visually in order to classify them according to the kind of defect (blood, feathers, and white, clear or dark feces), and clean eggshells were classified on the basis of the colour of the natural stains (clear or dark). For each sample digital images were acquired by employing a Charged Coupled Device (CCD) camera endowed with 15 monochromatic filters (440-940 nm). A Matlab® function was developed in order to automate the process and analyze images, with the aim to classify samples as clean or dirty. The program was constituted by three major steps: first, the research of an opportune combination of monochromatic images in order to isolate the eggshell from the background; second, the detection of the dirt stains; third, the classification of the images samples into the dirty or clean group on the basis of geometric characteristics of the stains (area in pixel). The proposed classification algorithm was able to correctly classify near 98% of the samples with a very low processing time (0.05s). The robustness of the proposed classification was observed applying an external validation to a second set of samples (n = 178), obtaining similar percentage of correctly classified samples (97%)

An automatic monitoring of the hatching process based on the noise of the hatching chicks

Trabajo AcadémicoOBJETIVO: SISTEMATIZAR LAS EVIDENCIAS SOBRE LA EFICACIA DE INTERVENCIONES PARA DISMINUIR LOS TRASTORNOS MUSCULOESQUELÉTICOS EN LOS TRABAJADORES. MATERIAL Y MÉTODO : EL ESTUDIO RESPONDE A UN DISEÑO DE REVISIÓN SISTEMÁTICA, CONSULTADO EN LA RECOPILACIÓN DE DATOS COMO BVS, SCIELO , PUBMED, GOOGLE ACADÉMICO, COCHRANE, MEDLINE, DIALNET, REALIZÁNDOSE UN ESTUDIO DE VERIFICACIÓN DE LOS ARTÍCULOS MEDIANTE EL SISTEMA GRADE, HERRAMIENTA QUE PERMITE EVALUAR LA VALIDACIÓN DE LA EVIDENCIA Y LA FUERZA DE RECOMENDACIÓN, DE LOS 10 ARTÍCULOS SELECCIONADOS EL 30% CORRESPONDE A EEUU, EL 20% A BRASIL Y EL 10% A ESPAÑA, CANADA, SUIZA Y PERÚ, RESPECTIVAMENTE. REFERENTE AL TIPO DE ESTUDIO Y DISEÑO EL 60% CORRESPONDE A REVISIONES SISTEMÁTICAS, EL 30% CUAXI EXPERIMENTAL, Y 10% ENSAYO CONTROLADO ALEATORIZADO. RESULTADOS: EL 60% DE ARTÍCULOS, DEMUESTRAN LA EFICACIA DE INTERVENCIONES PARA DISMINUIR LOS TRASTORNOS MUSCULOESQUELÉTICOS EN LOS TRABAJADORES, MIENTRAS EL 20% DEL TOTAL DE ARTÍCULOS DEMUESTRA NO EFICACIA EN LAS INTERVENCIONES. CONCLUSIONES: SE EVIDENCIÓ EN LAS INVESTIGACIONES REVISADAS QUE 6(10) ARTÍCULOS MUESTRAN EFICACIA PARA DISMINUIR LOS TRASTORNOS MUSCULOESQUELÉTICOS MEDIANTE LA INTERVENCIÓN DE LA APLICACIÓN DE EJERCICIOS POSTURALES EN LA ACTIVIDAD LABORAL; 2(10) ARTÍCULOS UTILIZAN COMO INTERVENCIÓN LA POSTURA CORPORAL Y DISEÑO DE ESTACIÓN DE TRABAJO; ASI COMO LA UTILIZACIÓN DE SILLAS AUTOAJUSTABLES, MIENTRAS 2(10) ARTÍCULOS HACEN REFERENCIA QUE NINGUNA INTERVENCIÓN ERGONÓMICA NO SON EFICACES EN DISMINUIR LOS TRASTORNOS MUSCULOESQUELÉTICOS

Semiautonomous development of the extraembryonic membranes in the chicken embryo.

Based on an old paradigm that the extra-embryonic membranes develop semiautonomously from the embryo, it can also be postulated that subembryonic fluid (SEF) will be formed semiautonomously against embryonic growth, because the formation of SEF is mediated by the yolk sac membrane. In this study, we interfered in the development of SEF or the embryo. The acoustic resonance technique (which measures the resonant frequency of an excited egg) was used as a nondestructive tool to monitor the development of SEF. In the first experiment, in which the embryo was killed chemically with NaN3, it was proven that the formation of SEF continued, even when the embryo was killed after the initiation of the growth of the yolk sac membrane. In the second experiment, in which the development of SEF was inhibited chemically with amiloride, it was shown that the embryo developed further, although SEF formation was inhibited. In the last experiment, it was shown that the age of the flock affected the development of the embryo and the sudden decrease of the resonant frequency in a different way. However, some presetting conditions, such as storage, may affect both in a similar way. Our results further strengthen the idea that the formation of SEF develops semiautonomously against embryonic development by using the nondestructive acoustic resonance technique as an indirect method to monitor yolk sac membrane formation