Theoretical overview on tau physics

Precise measurements of the tau lepton properties provide stringent tests of the Standard Model structure and accurate determinations of its parameters. We overview the present status of a few selected topics: lepton universality, QCD tests and the determination of alpha_s, m_s and V_us from hadronic tau decays, and lepton flavor violation phenomena.Comment: Invited talk at the International Workshop on Tau-Charm Physics (Charm2006), Beijing, China, June 5-7, 2006. 8 pages, 2 figure

The Hadronic Light-by-Light Contribution to the Muon Anomalous Magnetic Moment: Where do we stand?

We review the status of the hadronic light-by-light contribution to the muon anomalous magnetic moment and critically compare recent calculations. We also study in detail which momentum regions the pi^0 exchange main contribution originates. We also argue that a_\mu^{light-by-light} = (11 \pm 4) \times 10^{-10} encompasses the present understanding of this contribution and comment on some directions to improve on that.Comment: 16 pages, 9 figure

Physico-chemical properties of corn starch modified with cyclodextrin glycosyltransferase

Cyclodextrin glycosyltransferase (CGTase) has been used to produce cyclodextrins (CDs) from starches, but their ability to modify starches has been barely explored. The effect of CGTase on corn starch at sub-gelatinization temperature (50 °C) and at different pH conditions, pH 4.0 and pH 6.0, was evaluated. Biochemical features, thermal and structural analysis, oligosaccharides and CDs content were studied. Microscopic analysis of the granules confirmed the enzymatic modification of the starches obtaining structures with irregular surface and small pinholes. The extent of the starch modification was largely dependent on the pHs, being higher at pH 6.0. This was also confirmed by the low viscosity of the resulting pastes during a heating and cooling cycle. Thermal parameters were not affected due to enzymatic treatment. Modified starches were less susceptible to undergo α-amylase hydrolysis. CDs released were higher for samples treated at pH 4.0. Therefore, CGTase modification of corn starches at sub-gelatinization temperature offers an attractive alternative for obtaining porous starches with different properties depending on the pH conditions.Financial support of the Spanish Ministry of Economy and Competitiveness (Project AGL2011-23802, AGL2014-52928-C2-1-R), the European Regional Development Fund (FEDER) and Generalitat Valenciana (Project Prometeo 2012/064). A. Dura would like to thank predoctoral fellowship from Spanish Ministry of Economy and Competitiveness.Peer reviewe

Role of enzymes in improving the functionality of proteins in non-wheat dough systems

40 pages, 3 figures, 2 tables.-- Available online 25 September 2015Gluten free systems lack the viscoelastic network required to resist gas production and expansion during baking. Enzymatic treatments of the GF flours have been proposed initially for creating protein aggregates that mimic gluten functionality but then also for modifying proteins changing their functionality in GF systems. To better exploit the technological function and the potentials of enzymatic processing for improving GF bread quality, it is important to understand the key elements that define the microstructure and baking functionality of GF batters as compared to wheat dough. In this review, some keys are pointed out to explain the different mechanisms that are available for understanding the action of enzymes to effectively design GF viscoelastic matrixes. Focus will be on protein modifying enzymes, because they play a decisive role in the formation of the fine network responsible for improving the expansion of rice batters.Financial support of the Spanish Ministry of Economy and Competitiveness (Project AGL2014-52928-C2-1-R), the European Regional Development Fund (FEDER).Peer reviewe

Physicochemical properties of long rice grain varieties in relation to gluten free bread quality

30 pages, 3 figures, 7 tablesThe aim of this study was conducted to determine the breadmaking potential of six long-grain rice varieties (INIAP 14, INIAP 15, INIAP 16, INIAP 17, F09 and F50) and to identify any flour characteristic governing their breadmaking behavior. Pasting parameters, thermal parameters assessed by differential scanning calorimetry and bread quality parameters (specific volume, color, and crumb texture profile analysis) were assessed. Results confirmed the suitability of long-grain rice varieties for breadmaking. Nevertheless, significant differences were observed in flour properties among varieties. A significant correlation was observed between specific volume of the gluten-free bread (GFB) with swelling power (r = 0.71, P < 0.01), breakdown viscosity (r = −0.97, P < 0.01) and conclusion temperature (Tc) of gelatinization (r = 0.81, P < 0.05). Moreover, a strong correlation was found between cohesiveness and properties of rice flour such as peak temperature (Tp) (r = −0.96, P < 0.001), DH (r = 0.71 P < 0.05) and swelling volume (r = 0.82, P < 0.05). The quality characteristics of the gluten-free breads made of long-grain rice flour were comparable to those reported in commercial GFB. INIAP 14 and F09 were the most promising varieties for bakery applications. Results suggested that the most important parameters of rice flour when defining breadmaking performance of GFB would be WBC, SP, SV, Tp, Tc and enthalpy.financial support of Spanish Scientific Research Council (CSIC), the Spanish Ministry of Economy and Sustainability (Project AGL2011-23802), and the Generalitat Valenciana (Project Prometeo 2012/064). F. Cornejo acknowledges the financial support of National Secretary of High Education, Science, Technology and Innovation (SENESCYT, Ecuador).Peer reviewe

Influence of germination time of brown rice in relation to flour and gluten free bread quality

The effect of germination time on physicochemical characteristics of brown rice flour and its effect on gluten free bread qualities have been investigated. Germination was carried out at 28 °C and 100 % RH for 12, 24 and 48 h; brown rice and soaked brown rice was also analyzed. Significant changes on hydration and pasting properties of brown rice flour were found during germination. The starch degradation by enzyme activity could be evidenced with the decrease in viscosity and water binding capacity (WBC). No significant effect in specific volume, humidity and water activity of the gluten free bread was found as germination time increase, but a significant softness of the crumb was obtained. However, at 48 h of germination, the intense action of α amylase could result in excessive liquefaction and dextrinisation, causing inferior bread quality. Overall, germinated rice flour showed appropriate functionality for being used as raw ingredient in gluten free breadmaking.Authors acknowledge the financial support of Spanish Scientific Research Council (CSIC), the Spanish Ministry of Economy and Sustainability (Project AGL2011-23802), and the Generalitat Valenciana (Project Prometeo 2012/064). F. Cornejo acknowledges the financial support of Secretaría Nacional de Educación Superior, Ciencia, Tecnología e Innovación (SENESCYT, Ecuador). Instituto Nacional de Investigaciones Agropecuarias from Ecuador (INIAP) is thanked for providing the BR cultivars and Biotechnological Research Center of Ecuador (CIBE, Ecuador) for the laboratories facilitiesPeer Reviewe

Vanishing chiral couplings in the large-N_C resonance theory

The construction of a resonance theory involving hadrons requires implementing the information from higher scales into the couplings of the effective Lagrangian. We consider the large-Nc chiral resonance theory incorporating scalars and pseudoscalars, and we find that, by imposing LO short-distance constraints on form factors of QCD currents constructed within this theory, the chiral low-energy constants satisfy resonance saturation at NLO in the 1/Nc expansion.Comment: 5 pages, 2 figures. Version published in Physical Review D. Some equations to facilitate the discussion have been adde

Comparison of porous starches obtained from different enzyme types and levels

The objective was to compare the action of different hydrolases for producing porous corn starches. Amyloglucosidase (AMG), α-amylase (AM), cyclodextrin-glycosyltransferase (CGTase) and branching enzyme (BE) were tested using a range of concentrations. Microstructure, adsorptive capacity, pasting and thermal properties were assessed on the porous starches. SEM micrographs showed porous structures with diverse pore size distribution and pore area depending on the enzyme type and its level; AMG promoted the largest holes. Adsorptive capacity was significantly affected by enzymatic modification being greater influenced by AMG activity. Unexpectedly, amylose content increased in the starch treated with AMG and BE, and the opposite trend was observed in AM and CGTase treated samples, suggesting different mode of action. A heatmap illustrated the diverse pasting properties of the different porous starches, which also showed significant different thermal properties, with lower To and Tp. Porous starch properties could be modulated by using different enzymes and concentrations.Financial support of the Spanish Ministry of Economy and Competitiveness (Project AGL2014-52928-C2-1-R) and the European Regional Development Fund (FEDER). Y. Benavent-Gil would like to thank predoctoral fellowship from Spanish Ministry of Economy and Competitiveness.Peer reviewe