First-principles study of stability and vibrational properties of tetragonal PbTiO_3

A first-principles study of the vibrational modes of PbTiO_3 in the ferroelectric tetragonal phase has been performed at all the main symmetry points of the Brillouin zone (BZ). The calculations use the local-density approximation and ultrasoft pseudopotentials with a plane-wave basis, and reproduce well the available experimental information on the modes at the Gamma point, including the LO-TO splittings. The work was motivated in part by a previously reported transition to an orthorhombic phase at low temperatures [(J. Kobayashi, Y. Uesu, and Y. Sakemi, Phys. Rev. B {\bf 28}, 3866 (1983)]. We show that a linear coupling of orthorhombic strain to one of the modes at Gamma plays a role in the discussion of the possibility of this phase transition. However, no mechanical instabilities (soft modes) are found, either at Gamma or at any of the other high-symmetry points of the BZ.Comment: 8 pages, two-column style with 3 postscript figures embedded. Uses REVTEX and epsf macros. Also available at http://www.physics.rutgers.edu/~dhv/preprints/index.html#ag_pbt

Effect of prebiotic or probiotic supplementation and ileo rectal anastomosis on intestinal morphology of weaned piglets

Forty eight 21 days old piglets were used to compare the effect of prebiotic or probiotic supplementation and ileo rectal anastomosis on the morphology of the small intestine. Half of the piglets were maintained intact and the other half was subjected to an ileo rectal anastomosis (IRA). Each group of piglets received one of the following diets: 1) basal diet (C), 2) basal diet supplemented with a Xylo-oligosaccharide (XOS), 3) basal diet supplemented with a Saccharomyces cerevisiae (SC) and 4) basal diet supplemented with XOS and SC. Villus height was greatest with XOS and with XOS + SC, only in the ileum, as compared to controls. In the duodenum, crypt width was highest in the control group, but no significant differences were found in the jejunum and ileum. The IRA piglets had longer villi in the jejunum and shorter villi in the ileum. The crypt depth was greater in the duodenum and in the ileum of IRA piglets. Villus height/crypt depth was lower in the duodenum and in the ileum, in the IRA piglets. In conclusion, the XOS, but not the SC, moderately modified the intestinal morphology. The IRA modified the intestinal villus and crypt architecture but its consequence on the absorption of nutrients needs to be investigated

Insecticidal Effect Of Labramin, A Lectinlike Protein Isolated From Seeds Of The Beach Apricot Tree, Labramia Bojeri, On The Mediterranean Flour Moth, Ephestia Kuehniella

The objective of this work was to study the insecticidal effect of labramin, a protein that shows lectinlike properties. Labramin was isolated from seeds of the Beach Apricot tree, Labramia bojeri A. DC ex Dubard (Ericales: Sapotaceae), and assessed against the development of the Mediterranean flour moth Ephestia kuehniella Zeller (Lepidoptera: Pyralidae), an important pest of stored products such as corn, wheat, rice, and flour. Results showed that labramin caused 90% larval mortality when incorporated in an artificial diet at a level of 1% (w/w). The presence of 0.25% labramin in the diet affected the larval and pupal developmental periods and the percentage of emerging adults. Treatments resulted in elevated levels of trypsin activity in midgut and fecal materials, indicating that labramin may have affected enzymeregulatory mechanisms by perturbing peritrophic membranes in the midgut of is. kuehniella larvae. The results of dietary experiments with E. kuehniella larvae showed a reduced efficiency for the conversion of ingested and digested food, and an increase in approximate digestibility and metabolic cost. These findings suggest that labramin may hold promise as a control agent to engineer crop plants for insect resistance. © This is an open access paper. We use the Creative Commons Attribution 3.0 license that permits unrestricted use, provided that the paper is properly attributed.12Ayvaz, A., Osman, S., Salih, K., Ismet, O., Insecticidal activity of the essential oils from different plants against three stored-product insects (2008) Journal of Insect Science, 10, p. 21. , insectscience.org/10.21Boobis, A.R., Ossendorp, B.C., Banasiak, U., Hamey, P.Y., Sebestyen, I., Moretto, A., Cumulative risk assessment of pesticide residues in food (2008) Toxicology Letters, 15, pp. 137-150Boleti, A.P., Kubo, C.E.G., MacEdo, M.L.R., Effect of Pouterin, a protein from Pouteria torta (Sapotaceae) seeds, on the development of Ephestia kuehniella (Lepidoptera: Pyralidae) (2009) International Journal of Tropical Insect Science, 29, pp. 24-30Bradford, M.M., A rapid and sensitive method for the quantification of microgram quantities of protein using the principle of protein-dye binding (1976) Analytical Biochemistry, 72, pp. 248-254Carlini, C.R., Grossi-De-Sa, M.F., Plant toxic proteins with insecticidal properties. A review on their potentialities as bioinsecticides (2002) Toxicon, 40 (11), pp. 1515-1539. , DOI 10.1016/S0041-0101(02)00240-4, PII S0041010102002404Coelho, M.B., Marangoni, S., Macedo, M.L.R., Insecticidal action of Annona coriacea lectin against the flour moth Anagasta kuehniella and the rice moth Corcyra cephalonica (Lepidoptera: Pyralidae) (2007) Comparative Biochemistry and Physiology - C Toxicology and Pharmacology, 146 (3), pp. 406-414. , DOI 10.1016/j.cbpc.2007.05.001, PII S1532045607001354Eisemann, C.H., Donaldson, R.A., Pearson, R.D., Cadagon, L.C., Vacuolo, T., Tellman, R.L., Larvicidal activity of lectins on Lucilia cuprina: Mechanism of action (1994) Entomologia Experimentalis et Applicata, 72, pp. 1-11Fabre, C., Causse, H., Mourey, L., Koninkx, J., Riviere, M., Hendriks, H., Puzo, G., Rouge, P., Characterization and sugar-binding properties of arcelin-1, an insecticidal lectin-like protein isolated from kidney bean (Phaseolus vulgaris L. Cv. RAZ-2) seeds (1998) Biochemical Journal, 329 (3), pp. 551-560Farrar, R.R., Barbour, J.D., Kennedy, G.G., Quantifying food consumption and growth in insects (1989) Annals of the Entomological Society of America, 82, pp. 593-598Fitches, E., Gatehouse, A.M.R., Gatehouse, J.A., Effects of snowdrop lectin (GNA) delivered via artificial diet and transgenic plants on the development of tomato moth (Lacanobia oleracea) larvae in laboratory and glasshouse trials (1997) Journal of Insect Physiology, 43 (8), pp. 727-739. , DOI 10.1016/S0022-1910(97)00042-5, PII S0022191097000425Fitches, E., Gatehouse, J.A., A comparison of the short and long term effects of insecticidal lectins on the activities of soluble and brush border enzymes of tomato moth larvae (Lacanobia oleracea) (1998) Journal of Insect Physiology, 44 (12), pp. 1213-1224. , DOI 10.1016/S0022-1910(98)00090-0, PII S0022191098000900Fitches, E., Wiles, D., Douglas, A.E., Hinchliffe, G., Audsley, N., Gatehouse, J.A., The insecticidal activity of recombinant garlic lectins towards aphids (2008) Insect Biochemistry and Molecular Biology, 38, pp. 905-915Gatehouse, A.M., Powell, K.S., Peumans, W.J., Van Damme, E.J., Gatehouse, J.A., Insecticidal properties of plant lectins: Their potential in plant protection (1995) Lectins: Biomedical Perspectives, pp. 35-58. , Pusztai A, Bardocz S, Editors. Taylor and FrancisHarper, M.S., Hopkins, T.L., Czapla, T.H., Effect of wheat germ agglutinin on formation and structure of the peritrophic membrane in European corn borer (Ostrinia nubilalis) larvae (1998) Tissue and Cell, 30 (2), pp. 166-176. , DOI 10.1016/S0040-8166(98)80065-7Hosseininaveh, V., Bandani, A., Hosseininaveh, F., Digestive proteolytic activity in the Sunn pest, Eurygaster integriceps (2009) Journal of Insect Science, 9, p. 70. , insectscience.org/9.70Laemmili, U.K., Cleavage of structural proteins during the assembly of the head of bacteriophage T4 (1970) Nature, 227, pp. 680-685Lam, S.K., Ng, T.B., Lectins: Production and practical applications (2011) Applied Microbiology and Biotechnology, 89, pp. 45-55MacEdo, M.L.R., Fernandes, K.V.S., Sales, M.P., Xavier-Filho, J., Vicilins variants and the resistance of cowpea (Vigna unguiculata) seeds to the cowpea weevil (Callosobruchus maculatus) (1993) Comparative Biochemistry and Physiology, 105, pp. 84-94MacEdo, M.L.R., Durigan, R.A., Silva, D.S., Marangoni, S., Freire, M.G.M., Parra, J.R.P., Adenanthera pavonina trypsin inhibitor retard growth of Ephestia kuehniella (Lepidoptera: Pyralidae) (2010) Archives of Insect Biochemistry and Physiology, 73, pp. 213-231MacEdo, M.L.R., Damico, D.C.S., Freire, M.G.M., Toyama, M.H., Marangoni, S., Novello, J.C., Purification and characterization of an Nacetylglucosamine- binding lectin from Koelreuteria paniculata seeds and its effect on the larval development of Callosobruchus maculatus (Coleoptera: Bruchidae) and Ephestia kuehniella (Lepidoptera: Pyralidae) (2003) Journal of Agricultural and Food Chemistry, 51, pp. 2980-2986MacEdo, M.L.R., Freire, M.G.M., Martins, L.T.D.M., Martinez, D.S.T., Gomes, V.M., Smolka, M.B., Toyama, M.H., Coelho, L.C.B.B., Novel protein from Labramia bojeri A. DC. Seeds homologue to kunitz-type trypsin inhibitor with lectin-like properties (2004) Journal of Agricultural and Food Chemistry, 52, pp. 7548-7554Macedo, M.L.R., De Castro, M.M., Freire, M.D.G.M., Mechanisms of the insecticidal action of TEL (Talisia esculenta Lectin) against Callosobruchus maculatus (Coleoptera: Bruchidae) (2004) Archives of Insect Biochemistry and Physiology, 56 (2), pp. 84-96. , DOI 10.1002/arch.10145Macedo, M.L.R., Freire, M.D.G.M., Da Silva, M.B.R., Coelho, L.C.B.B., Insecticidal action of Bauhinia monandra leaf lectin (BmoLL) against Anagasta kuehniella (Lepidoptera: Pyralidae), Zabrotes subfasciatus and Callosobruchus maculatus (Coleoptera: Bruchidae) (2007) Comparative Biochemistry and Physiology - A Molecular and Integrative Physiology, 146 (4), pp. 486-498. , DOI 10.1016/j.cbpa.2006.01.020, PII S1095643306000316, Second Special Issue of CBP dedicated to "The Face of Latin American Comparative Biochemistry and Physiology"Machuka, J., Van Damme, E.J.M., Peumans, W.J., Jackai, L.E.N., Effect of plant lectins on larval development of the legume pod borer, Maruca vitrata (1999) Entomologia Experimentalis et Applicata, 93 (2), pp. 179-187. , DOI 10.1023/A:1003801120192Murdock, L.L., Shade, R.E., Lectins and protease inhibitors as plant defenses against insects (2002) Journal of Agricultural and Food Chemistry, 50 (22), pp. 6605-6611. , DOI 10.1021/jf020192cOliveira, C.F.R., Luz, L.A., Paiva, P.M.G., Coelho, L.C.B.B., Marangoni, S., MacEdo, M.L.R., Evaluation of seed coagulant Moringa oleifera lectin (cMoL) as a bioinsecticidal tool with potential for the control of insects (2011) Process Biochemistry, 46, pp. 498-504Pusztai, A., Ewen, S.W.B., Grant, G., Peumans, W.J., Van Damme, E.J.M., Rubio, L., Bardocz, S., Relationship between survival and binding of plant lectins during small intestinal passage and their effectiveness as growth factors (1990) Digestion, 46 (SUPPL. 2), pp. 308-316Scriber, J.M., Slansky Jr., F., He nutritional ecology of immature insects (1981) Annual Review of Entomology, 26, pp. 183-211Sharma, H.C., Sharma, K.K., Crouch, J.H., Genetic transformation of crops for insect resistance: Potential and limitations (2004) Critical Reviews in Plant Sciences, 23 (1), pp. 47-72. , DOI 10.1080/07352680490273400Srinivasan, A., Giri, A.P., Gupta, V.S., Structural and functional diversities in lepidopteran serine proteases (2006) Cellular and Molecular Biology Letters, 11 (1), pp. 132-154. , http://www.springerlink.com/content/r034203283014155/fulltext.pdf, DOI 10.2478/s11658-006-0012-8Terra, W.R., Ferreira, C., Jordao, B.P., Dilion, R.J., Digestive enzymes (1996) Biology of the Insect Midgut, pp. 153-194. , Lehane MJ, Billingsley PF, Editors. 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Dimensional Reduction, Hard Thermal Loops and the Renormalization Group

We study the realization of dimensional reduction and the validity of the hard thermal loop expansion for lambda phi^4 theory at finite temperature, using an environmentally friendly finite-temperature renormalization group with a fiducial temperature as flow parameter. The one-loop renormalization group allows for a consistent description of the system at low and high temperatures, and in particular of the phase transition. The main results are that dimensional reduction applies, apart from a range of temperatures around the phase transition, at high temperatures (compared to the zero temperature mass) only for sufficiently small coupling constants, while the HTL expansion is valid below (and rather far from) the phase transition, and, again, at high temperatures only in the case of sufficiently small coupling constants. We emphasize that close to the critical temperature, physics is completely dominated by thermal fluctuations that are not resummed in the hard thermal loop approach and where universal quantities are independent of the parameters of the fundamental four-dimensional theory.Comment: 20 pages, 13 eps figures, uses epsfig and pstrick

Do Instantons Like a Colorful Background?

We investigate chiral symmetry breaking and color symmetry breaking in QCD. The effective potential of the corresponding scalar condensates is discussed in the presence of non-perturbative contributions from the semiclassical one-instanton sector. We concentrate on a color singlet scalar background which can describe chiral condensation, as well as a color octet scalar background which can generate mass for the gluons. Whereas a non-vanishing singlet chiral field is favored by the instantons, we have found no indication for a preference of color octet backgrounds.Comment: 25 pages, 7 figure

Introduction to the functional RG and applications to gauge theories

These lectures contain an introduction to modern renormalization group (RG) methods as well as functional RG approaches to gauge theories. In the first lecture, the functional renormalization group is introduced with a focus on the flow equation for the effective average action. The second lecture is devoted to a discussion of flow equations and symmetries in general, and flow equations and gauge symmetries in particular. The third lecture deals with the flow equation in the background formalism which is particularly convenient for analytical computations of truncated flows. The fourth lecture concentrates on the transition from microscopic to macroscopic degrees of freedom; even though this is discussed here in the language and the context of QCD, the developed formalism is much more general and will be useful also for other systems.Comment: 60 pages, 14 figures, Lectures held at the 2006 ECT* School "Renormalization Group and Effective Field Theory Approaches to Many-Body Systems", Trento, Ital

Some Uses and Potentials of Qualitative Methods in Planning

Planners use methods borrowed from many disciplines. These are usually modified and adapted to meet planner's needs to acquire and sift through many diverse information sources helpful in dealing with complex problems. The quantitative methods which planners use are well known, well established in practice, and acknowledged by most as tools of the planners' trade. In contrast to this, most planners also use qualitative methods but these are rarely explicitly acknowledged.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68912/2/10.1177_0739456X8600600110.pd