ABSTRACT
We propose a general method (based on the Wang-Landau algorithm) to compute numerically free energies that are obtained from the logarithm of the ratio of suitable partition functions. As an application, we determine with high accuracy the order-order interface tension of the four-state Potts model in three dimensions on cubic lattices of linear extension up to L=56. The infinite volume interface tension is then extracted at each ß from a fit of the finite volume interface tension to a known universal behavior. A comparison of the order-order and order-disorder interface tension at ß(c) provides a clear numerical evidence of perfect wetting.
Subject(s)
Physics/methods , Surface Tension , Algorithms , Computer Simulation , Models, Statistical , Models, Theoretical , Monte Carlo Method , ThermodynamicsABSTRACT
Major hen egg white proteins have been widely studied for their functional properties but these studies still are unable to explain, alone, all of the biological properties of hen egg white. Hence, it is still interesting to produce pure and non-altered proteins to improve our knowledge on the biological properties of hen egg white. Presently, identification and characterization of both bioactive peptides and minor proteins from hen egg white is essential work for progressing in the understanding of hen egg white biological properties. With this objective in mind, a new process for a complete "mucin free" hen egg white fractionation based on ion exchange chromatography is proposed. "Mucin free" egg white is fractionated into six different fractions. Four of them are high-recovery yield purified fractions of lysozyme, ovotransferrin, ovalbumin and flavoprotein. The two other fractions are enriched in recently detected minor proteins in hen egg white.
Subject(s)
Chemical Fractionation/methods , Chromatography, Ion Exchange/methods , Egg White/analysis , Animals , Chickens , Chromatography, High Pressure Liquid , Conalbumin/isolation & purification , Electrophoresis, Polyacrylamide Gel , Female , Flavoproteins/isolation & purification , Isoelectric Focusing , Mass Spectrometry , Muramidase/isolation & purification , Ovalbumin/isolation & purificationABSTRACT
UNLABELLED: To facilitate optimal growth of newborns, many countries have developed infant feeding recommendations, usually suggesting 4-6 mo of exclusive breastfeeding and then the gradual introduction of complementary foods. We prospectively studied the changes in infant diets and predictors of adherence to national infant feeding recommendations in a cohort of 720 newborn babies in rural Malawi, Sub-Saharan Africa. Monthly interviews of the main guardians indicated that breastfeeding was universal for 18 mo. As most babies were given water or other supplemental foods soon after birth, the exclusive breastfeeding rates were only 19%, 8%, 2% and 0% at ages 1, 2, 3 and 4 mo, respectively. Complementary foods and family foods were introduced at median ages of 2.5 and 6.3 mo, i.e. much earlier than recommended. Better adherence to recommendations was associated with smaller number of children in the family, increased maternal education and some other socio-economic or environmental variables. CONCLUSION: Exclusive breastfeeding is uncommon and complementary foods were introduced early to newborns among these rural families. Education and family planning may improve adherence to infant feeding recommendations and reduce the incidence of early childhood malnutrition in Malawi.
