A random field model for quantitation and prediction of biological patterns †

A Markov random field model is proposed to quantitate and predict the formation of biological patterns. A tissue is viewed in two dimensions as an equally spaced lattice, the sites of which correspond to the centres of the cells. Each cell can be in either of two states: 0 or 1. In the case of a one cell-type tissue, the states represent different characteristics of the cell, e.g. healthy versus malignant. By estimating local interactions, we are able to quantitate the mechanisms inducing pattern formation and even predict the likelihood of specific patterns. Three examples are discussed: (1) alignment of enamel cells in the rat incisor, (2) quantitation of invasive capacity of one cell-type with oespect to another, and (3) sorting-out of two cell-types.     

PSYCHOLOGICAL TESTING THROUGH THE LOOKING GLASS OF YOUTH.

ATTEMPTED "TO EXAMINE HOW MUCH YOUNG AMERICANS (I.E., HIGH SCHOOL STUDENTS) KNOW ABOUT TESTING, THE EXTENT OF THEIR EXPOSURE TO VARIOUS TYPES OF PSYCHOLOGICAL TESTS, AND THEIR BELIEFS ABOUT THE EFFICACY OF THESE TESTS . . . . DATA ARE (ALSO) PRESENTED ON THEIR ATTITUDES TOWARD TESTING IN GENERAL AND IN THE SPECIFIC AREAS OF SCHOOL AND INDUSTRY." CERTAIN DEMOGRAPHIC VARIABLES RELATED TO THE ABOVE ARE CONSIDERED. 16,000 55-ITEM QUESTIONNAIRES WERE SENT TO THE PURDUE OPINION PANEL, WHICH CONSISTS OF 113 COOPERATING HIGH SCHOOLS. THERE WERE 12,000 RESPONDENTS. IT IS CONCLUDED THAT "WHILE ATTITUDES TOWARD PSYCHOLOGICAL TESTING ARE NOT OVERWHELMINGLY FAVORABLE IN THIS SAMPLE, THEY DO SEEM TO BE REASONABLY POSITIVE, AND HIGH SCHOOL STUDENTS DO EXPRESS CONSIDERABLE BELIEF IN THE UTILITY AND IMPARTIALITY OF PSYCHOLOGICAL TESTING." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

PROTEIN QUALITY OF FAFFA,THE ETHIOPIAN INFANT FORMULA AS AFFECTED BY PULSE SUBSTITUTION1

Faffa, the commercially produced infant formula in Ethiopia, contains approximately 20% protein derived from wheat, soy flour, chick peas and skimmilk. The paper examines the effect of substituting the chick peas in Faffa with haricot beans. Protein efficiency ratio (PER) was drastically reduced due to the substitution. Pre-toasting the haricot beans improved the PER value of the Faffa to the level of that of chick peas Faffa. The essential amino acid patterns of the two preparations of Faffa were found to be similar and therefore could not explain the difference in PER. It was suspected that improvement of PER by heat treatment of the haricot bean Faffa was due to inactivation of the trypsin inhibitor. Analysis for trypsin inhibitor content confirmed that the lower PER value for Faffa prepared from untoasted Faffa is due to higher trypsin inhibitor content of haricot beans as compared to chick peas.     

Effect of Calcium Salts on Susceptibility to Browning of Avocado Fruit

Fuerte avocados were dipped in 0.18M solutions of calcium chloride (CaCl₂·6H₂O) or calcium phosphate (CaHPO₄) or calcium arsenate [Cas(AsO₄)₂] or calcium nitrate [Ca(NO₃)₂·4H₂O] to determine whether these treatments had any effect on the browning components in avocados. It was found that calcium treatments suppressed both respiration and polyphenol oxidation and also reduced the content of total phenolics, leuco-anthocyanins, and flavonols. Of those calcium treatments used, calcium arsenate gave the best results.     

LINAMARASE: IMMOBILIZATION OF A CRUDE ENZYME

ABSTRACT Linamarase from cassava cortex was immobilized on polyacrylamide gel. A crude extract of the enzyme containing most of the intracellular proteins was used for the technique to simulate the enzyme in cassava. Immobilization of the enzyme increased the Michaelis constants for all substrates when compared with the native enzyme. Both free and immobilized linamarase hydrolyzed p-nitrophenylβ D-glucoside, linamarin and p-nitrophenylβ-D-galactoside. The immobilized enzyme was more stable than the free enzyme at room temperature (25C) and 41C. Both forms gave a bell-shaped curve with maximal activity at pH 6.0; these data indicated two catalytic ionizable residues with pK_a 5.7 and pK_a 6.5.     

STUDIES ON FLAVOR CHANGES DURING DRYING OF DILL (Anethum sowa Roxb.) LEAVES

Indian dill (Anethum sowa Roxb.) is a popular herb widely used in culinary preparations and is characterized by a persistent cineolic flavor. To study the flavor quality of the fresh and dried herb, it was subjected to through-flow, cross-flow, vacuum and freeze drying procedures. The volatile oils obtained from the fresh and dried samples were examined by gas chromatography and gas chromatography-mass spectrometry and the changes in their flavor compositions determined. Seventeen compounds have been identified in Indian dill leaf oil, of which β-cubebene is being reported for the first time. The proximate composition of the dried herb is also reported.     

Electrochemical,surface analytical and quantum chemical studies on Schiff bases of 4-amino-4H-1, 2, 4-triazole-3,5-dimethanol (ATD) in corrosion protection of aluminium in 1N HNO<Subscript>3</Subscript>

The present study describes the inhibition of aluminium in 1N HNO₃ with different concentrations of 1,2,4-triazole precursors ATD, BATD and DBATD using gravimetric method, potentiodynamic polarization studies (Tafel), electrochemical impedance spectroscopy (EIS), adsorption studies, surface morphological studies and quantum chemical calculations at 298 K. Polarization studies clearly showed that ATD, BATD and DBATD act as mixed type inhibitors. As the electron density around the inhibitor molecule increases due to substitution, the inhibition efficiency also increases correspondingly. Quantum chemical approach was used to calculate some electronic properties of the molecule to ascertain the correlation between inhibitive effect and molecular structure of the inhibitor. The corrosion inhibition efficiencies of these molecules and the global chemical reactivity relate to some parameters, such as E _HOMO , E _LUMO , gap energy (ΔE), electronegativity (χ), global hardness (η) and the fraction of electrons transferred from the inhibitor molecule to the metallic atom (DN\Delta \emph{N}). In addition, the local reactivity has been analysed through the Fukui function and condensed softness indices. Both the experimental and theoretical studies agree well in this regard and confirm that DBATD is a better inhibitor than BATD and ATD. The adsorption behaviours of molecules on the copper surface have been studied using molecular dynamics method and density functional theory. The order of inhibitory action is DBATD > BATD > ATD.