2,047 research outputs found

    An alternative order parameter for the 4-state Potts model

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    We have investigated the dynamic critical behavior of the two-dimensional 4-state Potts model using an alternative order parameter first used by Vanderzande [J. Phys. A: Math. Gen. \textbf{20}, L549 (1987)] in the study of the Z(5) model. We have estimated the global persistence exponent θg\theta_g by following the time evolution of the probability P(t)P(t) that the considered order parameter does not change its sign up to time tt. We have also obtained the critical exponents θ\theta, zz, ν\nu, and β\beta using this alternative definition of the order parameter and our results are in complete agreement with available values found in literature.Comment: 6 pages, 6 figure

    Partial Recovery Of Erythrocyte Glycogen In Diabetic Rats Treated With Phenobarbital

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    Erythrocytes may play a role in glucose homeostasis during the postprandial period. Erythrocytes from diabetic patients are defective in glucose transport and metabolism, functions that may affect glycogen storage. Phenobarbital, a hepatic enzyme inducer, has been used in the treatment of patients with non-insulin-dependent diabetes mellitus (NIDDM), increasing the insulin-mediated glucose disposal. We studied the effects of phenobarbital treatment in vivo on glycemia and erythrocyte glycogen content in control and alloxan-diabetic rats during the postprandial period. In control rats (blood glucose, 73 to 111 mg/dl in femoral and suprahepatic veins) the erythrocyte glycogen content was 45.4 ± 1.1 and 39.1 ± 0.8 μg/g Hb (mean ± SEM, N = 4-6) in the femoral artery and vein, respectively, and 37.9 ± 1.1 in the portal vein and 47.5 ± 0.9 in the suprahepatic vein. Diabetic rats (blood glucose, 300-350 mg/dl) presented low (P < 0.05) erythrocyte glycogen content, i.e., 9.6 ± 0.1 and 7.1 ± 0.7 μg/g Hb in the femoral artery and vein, respectively, and 10.0 ± 0.7 and 10.7 ± 0.5 in the portal and suprahepatic veins, respectively. After 10 days of treatment, phenobarbital (0.5 mg/ml in the drinking water) did not change blood glucose or erythrocyte glycogen content in control rats. In diabetic rats, however, it lowered (P < 0.05) blood glucose in the femoral artery (from 305 ± 18 to 204 ± 45 mg/dl) and femoral vein (from 300 ± 11 to 174 ± 48 mg/dl) and suprahepatic vein (from 350 ± 10 to 174 ± 42 mg/dl), but the reduction was not sufficient for complete recovery. Phenobarbital also stimulated the glycogen synthesis, leading to a partial recovery of glycogen stores in erythrocytes. In treated rats, erythrocyte glycogen content increased to 20.7 ± 3.8 μg/g Hb in the femoral artery and 30.9 ± 0.9 μg/g Hb in the suprahepatic vein (P < 0.05). These data indicate that phenobarbital activated some of the insulin-stimulated glucose metabolism steps which were depressed in diabetic erythrocytes, supporting the view that erythrocytes participate in glucose homeostasis.305657661Burant, C.F., Sivitz, W.I., Fukumoto, H., Kayano, T., Nagamatsu, S., Seino, S., Pessin, J.E., Bell, G.I., Mammalian glucose transporters: Structure and molecular regulation (1991) Recent Progress in Hormone Research, 47, pp. 1-41Zoccoli, M.A., Boldwin, S.A., Lienhard, G.E., Monosaccharide transport system of the human erythrocyte (1978) Journal of Biological Chemistry, 253, pp. 69213-69230Rapoport, S., The regulation of glycolysis in mammalian erythrocytes (1968) Essays in Biochemistry, 4, pp. 69-103Jacquez, J.A., Red blood cell as glucose carrier: Significance for placental and cerebral glucose transfer (1984) American Journal of Physiology, 246, pp. 289-298Ferranini, E., Bjorkman, O., Role of red blood cells in the regulation of blood glucose levels in man (1986) Diabetes, 35 (1 SUPPL.), p. 39. , AbstractGuarner, V., Alvarez-Buylla, R., Erythrocyte and glucose homeostasis in rats (1989) Diabetes, 38, pp. 410-415Hers, H.G., Verhue, W., Van Hoof, F., The determination of amylo-1,6-glucosidase (1967) European Journal of Biochemistry, 2, pp. 256-264Moses, S.W., Bashan, N., Gutman, A., Properties of glycogen synthetase in erythrocytes (1972) European Journal of Biochemistry, 30, pp. 205-210Garvey, W.T., Hueckstedt, T.P., Olefsky, J.M., Glucose and insulin co-regulate the glucose transport system in primary cultured adipocytes. A new mechanism of insulin resistance (1987) Diabetes, 36 (1 SUPPL.), p. 84. , AbstractRapin, J.R., Lespinasse, C., Yoa, R., Wiernsperger, N., Erythrocyte glucose consumption in insulin-dependent diabetes: Effect of metformin in vitro (1991) Diabete et Metabolisme, 14, pp. 164-167Lahtela, J.T., Sarkka, P., Sotaniemi, E.A., Phenobarbital treatment enhances insulin mediated glucose metabolism in man' (1984) Research Communications in Chemical Pathology and Pharmacology, 44, pp. 215-226Lahtela, J.T., Gachalyi, B., Eksyma, S., The effect of liver microsomal enzyme inducing and inhibiting drugs on insulin mediated glucose metabolism in man (1986) British Journal of Clinical Pharmacology, 21, pp. 19-26Lahtela, J.T., Arranto, A.J., Sotaniemi, E.A., Enzyme inducers improve insulin sensitivity in non-insulin-dependent diabetic subjects (1985) Diabetes, 34, pp. 911-916Farquharson, J., Jamieson, E.C., MacPhee, G.B., Logan, R.W., A new sensitive microassay for the measurement of erythrocyte glycogen (1990) Clinica Chimica Acta, 187, pp. 89-94Venkatsen, N., Davidson, M.B., Simsolo, R.B., Kern, P.A., Phenobarbital treatment enhances insulin-mediated glucose metabolism and improves lipid metabolism in the diabetic rat (1994) Metabolism: Clinical and Experimental, 43, pp. 348-356Thurman, R.G., Kauffman, F.C., Factors regulating drug metabolism in the intact hepatocytes (1980) Pharmacological Reviews, 31, pp. 229-251Karvonen, I., Stengard, J.H., Huupponen, R., Effects of enzyme induction therapy on glucose and drug metabolism in obese mice model of non-insulin dependent diabetes mellitus (1989) Diabetes Research, 10, pp. 85-92Villar-Palasi, C., Effect of glucose phosphorylation on the activation by insulin of skeletal muscle glycogen synthase (1995) Biochimica et Biophysica Acta, 1244, pp. 203-20

    Electron Spin Resonance G Shift In Gd5 Si4, Gd5 Ge4, And Gd5.09 Ge2.03 Si1.88

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    Gd5 Si4, Gd5 Ge4, and Gd5.09 Ge2.03 Si1.88 compounds were studied by electron spin resonance. The arc-melted samples were initially characterized by optical metallography, x-ray diffraction, and static magnetization measurements. The electron spin resonance results show a negative paramagnetic g shift for Gd5 Si4 and Gd5.09 Ge2.03 Si1.88, and a smaller positive one for Gd5 Ge4. The values of the exchange parameter (j) between the localized Gd-4f spins and the conduction electrons are obtained from the g shifts. These values are positive and of the same order of magnitude for Gd5 Si4 and Gd5.09 Ge2.03 Si1.88, and negative one order of magnitude smaller for Gd5 Ge4. The electron spin resonance data were interpreted considering the strongly bottlenecked solution of the coupled Bloch-Hasegawa equations. © 2006 The American Physical Society.7314Pecharsky, V.K., Gschneidner Jr., K.A., (1997) Phys. Rev. Lett., 78, p. 4494. , PRLTAO 0031-9007 10.1103/PhysRevLett.78.4494Pecharsky, V.K., Gschneidner Jr., K.A., (1997) J. Alloys Compd., 260, p. 98. , JALCEU 0925-8388 10.1016/S0925-8388(97)00143-6Choe, W., Pecharsky, V.K., Pecharsky, A.O., Gschneidner Jr., K.A., Young Jr., V.G., Miller, G.J., (2000) Phys. Rev. Lett., 84, p. 4617. , PRLTAO 0031-9007 10.1103/PhysRevLett.84.4617Levin, E.M., Pecharsky, V.K., Gschneidner Jr., K.A., (2000) Phys. Rev. B, 62, p. 14625. , PRBMDO 0163-1829 10.1103/PhysRevB.62.R14625Szade, J., Skorek, G., (1999) J. Magn. Magn. Mater., 196-197, p. 699. , JMMMDC 0304-8853Levin, E.M., Pecharsky, V.K., Gschneidner Jr., K.A., (1999) Phys. Rev. B, 60, p. 7993. , PRBMDO 0163-1829 10.1103/PhysRevB.60.7993Harmon, B.N., Antonov, V.N., (2002) J. Appl. Phys., 91, p. 9815. , JAPIAU 0021-8979 10.1063/1.1461896Levin, E.M., Pecharsky, V.K., Gschneidner Jr., K.A., Miller, G.J., (2001) Phys. Rev. B, 64, p. 235103. , PRBMDO 0163-1829 10.1103/PhysRevB.64.235103Skorek, G., Deniszczyk, J., Szade, J., (2002) J. Phys.: Condens. Matter, 14, p. 7273. , JCOMEL 0953-8984 10.1088/0953-8984/14/30/316Samolyuk, G.D., Antropov, V.P., (2002) J. Appl. Phys., 91, p. 8540. , JAPIAU 0021-8979 10.1063/1.1455614Pecharsky, V.K., Samolyuk, G.D., Antropov, V.P., Pecharsky, A.O., Gschneidner Jr., K.A., (2003) Solid State Chem., 171, p. 57. , 29CBA6Pires, M.J.M., Magnus Carvalho G, A., Gama, S., Da Silva, E.C., Coelho, A.A., Mansanares, A.M., (2005) Phys. Rev. B, 72, p. 224435. , PRBMDO 0163-1829 10.1103/PhysRevB.72.224435Gama, S., Alves, C.S., Coelho, A.A., Ribeiro, C.A., Persiano, A.I.C., Silva, D., (2004) J. Magn. Magn. Mater., 272-276, p. 848. , JMMMDC 0304-8853Usenko, N.I., Ivanov, M.I., Berezutski, V.V., Polotska, R.I., (1998) J. Alloys Compd., 266, p. 186. , JALCEU 0925-8388Zipper, E., (1982) J. Phys. F: Met. Phys., 12, p. 3123. , JPFMAT 0305-4608Glaunsinger, W.S., (1976) J. Phys. Chem. Solids, 37, p. 51. , JPCSAW 0022-3697 10.1016/0022-3697(76)90179-7Kaczmarska, K., (1996) J. Alloys Compd., 240, p. 88. , JALCEU 0925-8388Barnes, S.E., (1981) Adv. Phys., 30, p. 801. , ADPHAH 0001-8732 10.1080/00018738100101447Taylor, R.H., Coles, B.R., (1975) J. Phys. F: Met. Phys., 5, p. 121. , JPFMAT 0305-4608 10.1088/0305-4608/5/1/017Kaczmarska, K., Kwapulińska, E., Lebarski, A., Zipper, E., Chelkowski, A., (1985) J. Magn. Magn. Mater., 50, p. 101. , JMMMDC 0304-8853Schütz, G., Knülle, M., Wienke, R., Wilhelm, W., Wagner, W., Kienle, P., Frahm, R., (1988) Z. Phys. B: Condens. Matter, 73, p. 67. , ZPCMDN. 0722-3277. 10.1007/BF01312156Kim, J.W., Lee, Y., Wermeille, D., Sieve, B., Tan, L., Bud'Ko, S.L., Law, S., Goldman, A.I., (2005) Phys. Rev. B, 72, p. 064403. , PRBMDO 0163-1829 10.1103/PhysRevB.72.064403Lee, Y., Kim, J.W., Goldman, A.I., Harmon, B.N., (2005) J. Appl. Phys., 97, pp. 10A311. , JAPIAU 0021-8979 10.1063/1.185221

    Adsortividade do herbicida "Zeta" em solos de variadas texturas

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    To estimate the herbicide rate which inhibits 50% (I50) of the growth of bioindicator plants in soils of different textures and organic matter levels, which could interfere on the bioactivity of the tested herbicide, a completely randomized experiment was carried out with seven treatments (0, 50, 100, 150, 200, 250 and 300 g a.i./ ha) and four replications, in five kinds of soil textures. The analyzed parameters were: total fresh biomass, dry shoot biomass and dry root biomass of the sorghum plants. According to the results, it can be concluded that in sandy soils the herbicide shows a great vertical mobility, and that high levels of AP+ in the soil can minimize the herbicide effect on plants. The experiment also has shown that the higher the level of active clays and of organic matter in the soil, the higher the rate of herbicide required for a given weed control level.Com o objetivo de estimar a dose do herbicida "Zeta" que inibe 50% I50) do crescimento de plantas bioindicadoras em solos com diferentes texturas e teores de matéria orgânica, podendo estes ter uma influência marcante sobre a bioatividade do herbicida testado, utilizou-se o delineamento experimental inteiramente casualizado com 7 tratamentos (0, 50, 100, 150, 200, 250 e 300 g i.a./ha) e 4 repetições, sendo os tratamentos dispostos em 5 tipos de texturas de solo. Os parâmetros avaliados foram: biomassa fresca total, biomassa seca da parte aérea e biomassa seca do sistema radicular das plantas de sorgo. De acordo com os resultados obtidos pode-se concluir que em solos com textura tendendo à arenosa o herbicida apresenta uma grande mobilidade vertical, e que altos teores de AP+ no solo podem mascarar, de certa forma, a atuação do herbicida na planta. Em linhas gerais, o experimento permitiu inferir que quanto maior os teores de argilas ativas e de matéria orgânica presentes no solo, maior a dose do herbicida requerida para um dado controle percentual de plantas daninhas

    On the consistency of the three-dimensional noncommutative supersymmetric Yang-Mills theory

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    We study the one-loop quantum corrections to the U(N) noncommutative supersymmetric Yang-Mills theory in three spacetime dimensions (NCSYM3_3). We show that the cancellation of the dangerous UV/IR infrared divergences only takes place in the fundamental representation of the gauge group. Furthermore, in the one-loop approximation, the would be subleading UV and UV/IR infrared divergences are shown to vanish.Comment: 8 pages and 2 figure

    Magnetocaloric Effect And Evidence Of Superparamagnetism In Gda L2 Nanocrystallites: A Magnetic-structural Correlation

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    The correlation between structural and magnetic properties of GdAl2, focusing on the role played by the disorder in magnetic ordering and how it influences the magnetocaloric effect (MCE) are discussed. Micrometric-sized particles, consisting of nanocrystallites embedded in an amorphous matrix, were prepared by a mechanical milling technique and characterized by means of x-ray diffraction, scanning and high-resolution transmission electron microscopy as well as magnetic measurements as a function of an applied external magnetic field and temperature. The results show that the average particle size is just slightly diminished (≈7%) with the milling time (between 3 and 13 h), whereas the average crystallite size undergoes an expressive reduction (≈43%). For long milling times, structural disorders mostly associated with crystallite size singularly affect the magnetic properties, leading to a large tablelike MCE in the temperature range between 30 and 165 K. Below 30 K, nanocrystallites with dimensions below a given critical size cause an enhancement in the magnetic entropy change related to superparamagnetic behavior. In contrast, for low milling times, relative cooling power values are improved. These striking features along with the small magnetic hysteresis observed make the milled GdAl2 a promising material for application in the magnetic refrigeration technology. Finally, a discussion in an attempt to elucidate the origin of the spin-glass states previously reported in the literature for mechanically milled GdAl2 samples for very long times (400 and 1000 h) is presented. © 2016 American Physical Society.93

    Milk production in saanen goats treated with repeated low doses of intermediate-release insulin during early lactation

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    The effect of insulin administration on the productive responses of Saanen goats during early lactation was investigated. Ten of 20 adult females were subjected to subcutaneous administration of intermediate-acting insulin (0.14UI/kg body weight) at 2, 9, and 14 days postpartum. Milk yield was measured twice daily for 13 weeks and milk samples were collected to measure protein and fat contents. Plasma levels of progesterone, insulin, non-esterifies fatty acids, glucose and other metabolites were measured. Results showed a significantly increased effect of insulin treatment on the content of milk fat and protein; moreover, milk production in the first and second postpartum weeks were higher than control group. The peak of lactation in the insulin group was achieved one week earlier in comparison to the control group. In addition, the milk production rate showed lower persistency (milk yield 13 week/milk yield at peak) in the same group. During the first four weeks of postpartum, treated animals showed greater weight loss and higher non-esterified fatty acid concentration, whereas no effect was observed on the concentration of progesterone and other metabolites. The above results indicated that repeated administration of insulin in dairy goats during early lactation increase yield and qualitative components of milk, but has substantial consequences on animal productive rate and metabolic response

    Dietary xylanase and live yeast supplementation influence intestinal bacterial populations and growth performance of piglets fed a sorghum-based diet

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    This study was to evaluate the effect of xylanase supplementation and the addition of live yeast, Saccharomyces cerevisiae, on growth performance and intestinal microbiota in piglets. One hundred and eighty commercial crossbred 23-d-old piglets (PIC 417) were sorted by initial BW and allocated to 3 treatments: control (CTR) diet, CTR diet supplemented with xylanase at 16,000 birch xylan units/kg (XYL) and XYL diet supplemented with live yeast (2 × 10 10 CFU/g) at 1 kg/t (XYL + LY). Each treatment had 10 replicates, with 6 animals each. A sorghum-based diet and water were available ad libitum for 42 d of the study. Average daily gain (ADG) and average daily feed intake (ADFI) were measured from 0 to 42 d (23- to 65-d-old) and feed conversion ratio (FCR) calculated. At the end of the study, bacterial identification through 16S rRNA (V3 to V4) sequencing of the ileal and caecal digesta from one piglet per replicate was performed. No treatment effects were observed on ADFI. Pigs offered the live yeast in addition to the xylanase had increased ADG compared with those supplemented with xylanase alone (XYL + LY vs. XYL; P = 0.655). FCR was improved with XYL and XYL + LY compared with CTR (P = 0.018). Clostridiaceae counts in the ileum tended to reduce by 10% with XYL and 14% with XYL + LY compared to CTR (P = 0.07). XYL and XYL + LY increased the counts of Lactobacillaceae in the caecum compared with CTR (P < 0.0001). Dietary supplementation of live yeast combined with xylanase improved growth performance and microbial balance of piglets during the nursery phase
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