Brain Routes for Reading in Adults with and without Autism: EMEG Evidence

Reading utilises at least two neural pathways. The temporal lexical route visually maps whole words to their lexical entries, whilst the nonlexical route decodes words phonologically via parietal cortex. Readers typically employ the lexical route for familiar words, but poor comprehension plus precocity at mechanically ‘sounding out’ words suggests that differences might exist in autism. Combined MEG/EEG recordings of adults with autistic spectrum conditions (ASC) and controls while reading revealed preferential recruitment of temporal areas in controls and additional parietal recruitment in ASC. Furthermore, a lack of differences between semantic word categories was consistent with previous suggestion that people with ASC may lack a ‘default’ lexical-semantic processing mode. These results are discussed with reference to dual-route models of reading

Effects of isolated soy protein on blood pressure and altered glucose metabolism in the heart muscle of dyslipemic insulin–resistant rats

El objetivo del trabajo fue analizar los efectos de la administración de proteína de soja aislada, sobre la hipertensión y alteraciones del metabolismo de la glucosa presentes en el músculo cardíaco de ratas dislipémicas insulino resistentes, inducidas por una ingesta crónica de una dieta rica en sacarosa (DRS). Ratas machos Wistar recibieron durante 4 meses DRS. Finalizado este período, la mitad de los animales continuó con la DRS y en la otra mitad la proteína de soja aislada sustituyó a la caseína como fuente proteica (DRS+PS) durante 4 meses adicionales. El grupo control (DC) consumió dieta control durante toda la experiencia. Los resultados alcanzados demuestran que ésta manipulación dietaría fue capaz de revertir la hipertensión arterial normalizando la alterada fosforilación de la glucosa estimada por la actividad hexoquinasa- y el contenido de glucosa-6-fosfato y glucógeno en el musculo cardiaco. La sustitución de caseína por proteína de soja como fuente proteica normalizó los niveles plasmáticos de triglicéridos, ácidos grasos no esterificados y la moderada hiperglucemia sin cambios en la insulinemia. La sensibilidad insulinica periférica global mejoró notablemente aunque sin alcanzar valores del grupo DC. Los resultados obtenidos muestran a la proteína de soja dietaría como una herramienta nutricional capaz de normalizar la presión arterial, la fosforilación y la vía no oxidativa de la glucosa en el músculo cardíaco en este modelo experimental.The present study analyzes the effect of dietary isolated soy protein on hypertension and impaired glucose metabolism present in the heart muscle of dyslipemic insulin– resistant rats fed a sucrose–rich diet (SRD). Male Wistar rats received a SRD for 4 months. At this time half of the animals continue with the same diet for up to 8 months, the other half was fed an SRD in which isolated soy protein replaced casein as protein source (DRS+PS) for 4 additional months. The control group (CD) consumed control diet throughout the experimental diet. The results obtained show that this dietary manipulation was able to reverse the hypertension normalizing the altered glucose phosphorylation -estimated by hexokinase activity- and glucose 6-phosphate and glycogen content in the heart muscle of SRD fed rats. The replacement of soy protein by casein as protein source normalized plasma levels of triglycerides, NEFA and the moderate hyperglycemia without change of insulinemia. Although the whole body peripheral insulin sensitivity improved significantly values were still higher than those of CD group. The results showed that the dietary soy protein could be a nutritional tool capable to normalized blood pressure, and heart muscle glucose phosphorylation as well as the nonoxidative pathway of glucose in this experimental animal model.Fil: Oliva, Maria Eugenia. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Departamento de Ciencias Biológicas. Cátedra de Química Biológica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Chicco, Adriana Graciela. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Departamento de Ciencias Biológicas. Cátedra de Química Biológica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Lombardo, Y. B.. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Departamento de Ciencias Biológicas. Cátedra de Química Biológica; Argentin

Large-N spacetime reduction and the sign and silver-blaze problems of dense QCD

We study the spacetime-reduced (Eguchi-Kawai) version of large-N QCD with nonzero chemical potential. We explore a method to suppress the sign fluctuations of the Dirac determinant in the hadronic phase; the method employs a re-summation of gauge configurations that are related to each other by center transformations. We numerically test this method in two dimensions, and find that it successfully solves the silver-blaze problem. We analyze the system further, and measure its free energy F, the average phase theta of its Dirac determinant, and its chiral condensate . We show that F and are independent of mu in the hadronic phase but that, as chiral perturbation theory predicts, the quenched chiral condensate drops from its mu=0 value when mu~(pion mass)/2. Finally, we find that the distribution of theta qualitatively agrees with further, more recent, predictions from chiral perturbation theory.Comment: 43 pages, 17 figure

Equation of state in the PNJL model with the entanglement interaction

The equation of state and the phase diagram in two-flavor QCD are investigated by the Polyakov-loop extended Nambu--Jona-Lasinio (PNJL) model with an entanglement vertex between the chiral condensate and the Polyakov-loop. The entanglement-PNJL (EPNJL) model reproduces LQCD data at zero and finite chemical potential better than the PNJL model. Hadronic degrees of freedom are taken into account by the free-hadron-gas (FHG) model with the volume-exclusion effect due to the hadron generation. The EPNJL+FHG model improves agreement of the EPNJL model with LQCD data particularly at small temperature. The quarkyonic phase survives, even if the correlation between the chiral condensate and the Polyakov loop is strong and hadron degrees of freedom are taken into account. However, the location of the quarkyonic phase is sensitive to the strength of the volume exclusion.Comment: 9 pages, 7 figure

A model of semimetallic behavior in strongly correlated electron systems

Metals with values of the resistivity and the Hall coefficient much larger than typical ones, e.g., of sodium, are called semimetals. We suggest a model for semimetals which takes into account the strong Coulomb repulsion of the charge carriers, especially important in transition-metal and rare-earth compounds. For that purpose we extend the Hubbard model by coupling one additional orbital per site via hybridization to the Hubbard orbitals. We calculate the spectral function, resistivity and Hall coefficient of the model using dynamical mean-field theory. Starting from the Mott-insulating state, we find a transition to a metal with increasing hybridization strength (``self-doping''). In the metallic regime near the transition line to the insulator the model shows semimetallic behavior. We compare the calculated temperature dependence of the resistivity and the Hall coefficient with the one found experimentally for $\rm Yb_4As_3$. The comparison demonstrates that the anomalies in the transport properties of $\rm Yb_4As_3$ possibly can be assigned to Coulomb interaction effects of the charge carriers not captured by standard band structure calculations.Comment: 9 pages RevTeX with 7 ps figures, accepted by PR

Thermodynamics of two-colour QCD and the Nambu Jona-Lasinio model

We investigate two-flavour and two-colour QCD at finite temperature and chemical potential in comparison with a corresponding Nambu and Jona-Lasinio model. By minimizing the thermodynamic potential of the system, we confirm that a second order phase transition occurs at a value of the chemical potential equal to half the mass of the chiral Goldstone mode. For chemical potentials beyond this value the scalar diquarks undergo Bose condensation and the diquark condensate is nonzero. We evaluate the behaviour of the chiral condensate, the diquark condensate, the baryon charge density and the masses of scalar diquark, antidiquark and pion, as functions of the chemical potential. Very good agreement is found with lattice QCD (N_c=2) results. We also compare with a model based on leading-order chiral effective field theory.Comment: 24 pages, 12 figure

Islet neogenesis: An apparent key component of long-term pancreas adaptation to increased insulin demand

This study aimed to determine the relative importance of different functional and morphological pancreatic changes induced by the chronic administration of a sucrose-rich diet (SRD) to maintain normal glucose homeostasis. Male Wistar rats were fed either sucrose (SRD) or starch (CD) for 6 and 12 months. At both periods, serum glucose and triacylglycerol levels were significantly higher (P<0.05; paired and unpaired Student's t-test) in SRD rats. Serum insulin levels were significantly lower in SRD only at 12 months. At 6 months, the insulin secretion dose-response curve in SRD rats showed a shift to the left that was no longer observed at 12 months, when SRD islets decreased their response to 16 mM glucose. At 6 months, SRD rats showed a significant increase in β-cell volume density (Vvi) and islet cell replication rate, together with a decrease in β-cell apoptotic rate. Changes were not detected in the percentage of PDX-1- and islet neogenesis associated protein (INGAP)-positive cells. Conversely, at 12 months, there was a significant decrease in β-cell Vvi and in the percentage of PDX-1-positive cells; the islet cell replication rate was not modified, and the number of apoptotic β-cells increased significantly. No signs of increased neogenesis or INGAP-positive cells were recorded at any period in SRD rats. Our results show that SRD rats are unable to develop functional and morphological pancreatic reactive changes sufficient to maintain normal glucose and triacylglycerol levels for a long period. Such failure could be ascribed to their inability to increase the rate of neogenesis and of INGAP production.Centro de Endocrinología Experimental y Aplicad

Islet neogenesis: An apparent key component of long-term pancreas adaptation to increased insulin demand

This study aimed to determine the relative importance of different functional and morphological pancreatic changes induced by the chronic administration of a sucrose-rich diet (SRD) to maintain normal glucose homeostasis. Male Wistar rats were fed either sucrose (SRD) or starch (CD) for 6 and 12 months. At both periods, serum glucose and triacylglycerol levels were significantly higher (P<0.05; paired and unpaired Student's t-test) in SRD rats. Serum insulin levels were significantly lower in SRD only at 12 months. At 6 months, the insulin secretion dose-response curve in SRD rats showed a shift to the left that was no longer observed at 12 months, when SRD islets decreased their response to 16 mM glucose. At 6 months, SRD rats showed a significant increase in β-cell volume density (Vvi) and islet cell replication rate, together with a decrease in β-cell apoptotic rate. Changes were not detected in the percentage of PDX-1- and islet neogenesis associated protein (INGAP)-positive cells. Conversely, at 12 months, there was a significant decrease in β-cell Vvi and in the percentage of PDX-1-positive cells; the islet cell replication rate was not modified, and the number of apoptotic β-cells increased significantly. No signs of increased neogenesis or INGAP-positive cells were recorded at any period in SRD rats. Our results show that SRD rats are unable to develop functional and morphological pancreatic reactive changes sufficient to maintain normal glucose and triacylglycerol levels for a long period. Such failure could be ascribed to their inability to increase the rate of neogenesis and of INGAP production.Centro de Endocrinología Experimental y Aplicad

A New Theory of Stochastic Inflation

The stochastic inflation program is a framework for understanding the dynamics of a quantum scalar field driving an inflationary phase. Though widely used and accepted, there have over recent years been serious criticisms of this theory. In this paper I will present a new theory of stochastic inflation which avoids the problems of the conventional approach. Specifically, the theory can address the quantum-to-classical transition problem, and it will be shown to lead to a dramatic easing of the fine tuning constraints that have plagued inflation theories.Comment: 28 pages in latex (uses revtex), no figures. Changes include 3 pages of extra detail in the derivation of the noise and dissipation kernels, and a more careful description of the approximations made. Results remain unchange

Nuclear Alpha-Particle Condensates

The $\alpha$-particle condensate in nuclei is a novel state described by a product state of $\alpha$'s, all with their c.o.m. in the lowest 0S orbit. We demonstrate that a typical $\alpha$-particle condensate is the Hoyle state ($E_{x}=7.65$ MeV, $0^+_2$ state in $^{12}$C), which plays a crucial role for the synthesis of $^{12}$C in the universe. The influence of antisymmentrization in the Hoyle state on the bosonic character of the $\alpha$ particle is discussed in detail. It is shown to be weak. The bosonic aspects in the Hoyle state, therefore, are predominant. It is conjectured that $\alpha$-particle condensate states also exist in heavier $n\alpha$ nuclei, like $^{16}$O, $^{20}$Ne, etc. For instance the $0^+_6$ state of $^{16}$O at $E_{x}=15.1$ MeV is identified from a theoretical analysis as being a strong candidate of a $4\alpha$ condensate. The calculated small width (34 keV) of $0^+_6$, consistent with data, lends credit to the existence of heavier Hoyle-analogue states. In non-self-conjugated nuclei such as $^{11}$B and $^{13}$C, we discuss candidates for the product states of clusters, composed of $\alpha$'s, triton's, and neutrons etc. The relationship of $\alpha$-particle condensation in finite nuclei to quartetting in symmetric nuclear matter is investigated with the help of an in-medium modified four-nucleon equation. A nonlinear order parameter equation for quartet condensation is derived and solved for $\alpha$ particle condensation in infinite nuclear matter. The strong qualitative difference with the pairing case is pointed out.Comment: 71 pages, 41 figures, review article, to be published in "Cluster in Nuclei (Lecture Notes in Physics) - Vol.2 -", ed. by C. Beck, (Springer-Verlag, Berlin, 2011