932 research outputs found

    Comparison of 30 THz impulsive burst time development to microwaves, H-alpha, EUV, and GOES soft X-rays

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    The recent discovery of impulsive solar burst emission in the 30 THz band is raising new interpretation challenges. One event associated with a GOES M2 class flare has been observed simultaneously in microwaves, H-alpha, EUV, and soft X-ray bands. Although these new observations confirm some features found in the two prior known events, they exhibit time profile structure discrepancies between 30 THz, microwaves, and hard X-rays (as inferred from the Neupert effect). These results suggest a more complex relationship between 30 THz emission and radiation produced at other wavelength ranges. The multiple frequency emissions in the impulsive phase are likely to be produced at a common flaring site lower in the chromosphere. The 30 THz burst emission may be either part of a nonthermal radiation mechanism or due to the rapid thermal response to a beam of high-energy particles bombarding the dense solar atmosphere.Comment: accepted to Astronomy and Astrophysic

    Morphological and Molecular Characterization of Grapevine Accessions Known as Albillo

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    Twenty-eight accessions identified under the name of Albillo or cited as a synonym of this ancient Spanish grapevine variety were characterized using 43 morphological descriptors, four different isozyme systems (CO, ACPH, GOT, and SOD) and two Amplified Fragment Length Polymorphism (AFLP) primer combinations. Genetic similarity data resulting from these analyses allowed three different groups of Albillo to be distinguished that corresponded with geographical and historical origin of representative varieties: Turruntés, Malvasía de El Bierzo, and the classical Albillo de Madrid, related to the oldest Albillo ampelographical descriptions. In addition, homonyms as well as varieties incorrectly cited as Albillo synonyms were identified. To ensure accurate variety identification, association among historical descriptions based on morphological descriptors and molecular fingerprints was required. Isozymes proved to be useful markers for varietal identification. However, only AFLP allowed distinction among closely related varieties as well as the analysis of intravarietal variation.M.T.C. was funded by a Ministerio de Educación y Cultura contract; I.R., J.A.C., and J.C. were funded by predoctoral fellowships from the European Union, Instituto Nacional de Investigaciones Agrarias y Agroalimentarias, and Agencia Española de Cooperación Internacional, respectively. This research was funded in part by projects INIA SC96-010, SC94-092, and CM 07B-0010-1997. Support for research activity at the Centro Nacional de Biotecnología is provided by a CSIC-INIA specific agreement.Peer reviewe

    Characterization of genetic variation within table grape varieties (Vitis vinifera L.) based on AFLP markers

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    AFLPs were used to characterize a collection of 35 table grape varieties. A single AFLP reaction with a single combination of selective primers yielded an average of 50 polymorphic and scorable amplified bands in this collection and was enough to unequivocally identify each analyzed variety, Genetic similarity between different varieties was estimated, based on the results obtained with two primer combinations, to be between 0.65 and 0.90, while sibling varieties derived from the same cross showed a genetic similarity higher than 0.80, The analysis of several samples belonging to the same varieties, yet from different origins, showed stability of the AFLP patterns as to unequivocally and reproducibly identify them. Furthermore, some specific primer combinations detected a low level of variation that could be due to somatic variation and would be useful in clonal identification

    Varietal diversity within grapevine accessions of cv. Tempranillo

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    Intra-varietal diversity of 31 accessions named as Tempranillo or described as synonyms of this representative Spanish grapevine variety was assessed using 48 morphological descriptors and 95 AFLP markers obtained using 2 primer combinations. We could identify homonyms as well as accessions belonging to varieties which, depending on their regional origin, are incorrectly cited as Tempranillo synonyms. Genetic analysis revealed a high level of genetic similarity between Tempranillo accessions (SG >0.97), which could correspond to three highly related genotypes. This narrow genetic variation supports a monophyletic origin of Tempranillo, and could be the result of rapid multiplication and distribution of a very low number of clones.

    Gab2 deficiency prevents Flt3-ITD driven acute myeloid leukemia in vivo

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    Internal tandem duplications (ITD) of the FMS-like tyrosine kinase 3 (FLT3) predict poor prognosis in acute myeloid leukemia (AML) and often co-exist with inactivating DNMT3A mutations. In vitro studies implicated Grb2-associated binder 2 (GAB2) as FLT3-ITD effector. Utilizing a Flt3-ITD knock-in, Dnmt3a haploinsufficient mouse model, we demonstrate that Gab2 is essential for the development of Flt3-ITD driven AML in vivo, as Gab2 deficient mice displayed prolonged survival, presented with attenuated liver and spleen pathology and reduced blast counts. Furthermore, leukemic bone marrow from Gab2 deficient mice exhibited reduced colony-forming unit capacity and increased FLT3 inhibitor sensitivity. Using transcriptomics, we identify the genes encoding for Axl and the Ret co-receptor Gfra2 as targets of the Flt3-ITD/Gab2/Stat5 axis. We propose a pathomechanism in which Gab2 increases signaling of these receptors by inducing their expression and by serving as downstream effector. Thereby, Gab2 promotes AML aggressiveness and drug resistance as it incorporates these receptor tyrosine kinases into the Flt3-ITD signaling network. Consequently, our data identify GAB2 as a promising biomarker and therapeutic target in human AML

    Comparison of different model solutions to simulate membrane fouling in the ultrafiltration of a secondary effluent from a municipal wastewater treatment plant

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    The quality of the secondary treatment effluent (STE) from a municipal wastewater treatment plant (MWWTP) is not good enough for some applications such as agriculture. Membrane ultrafiltration (UF) has been proven to be a reliable tertiary treatment to achieve the needed water quality. The productivity of the UF processes depends on the membrane fouling. The aim of this work is to prepare a model wastewater that could mimic the fouling trend of a STE wastewater from a MWWTP. Several model wastewaters consisting of different proteins and carbohydrates were used in the UF experiments. UF was also performed with a STE. The membrane used in the UF tests was a UFCM5 from Norit X-flow® hydrophilic polyethersulfone/polyvinylpyrrolidone blend hollow-fiber UF membrane of 200 KDa molecular weight cut-off with a fiber diameter of 1.5 mm. Membrane configuration was inside-out. UF tests with model wastewater and STE wastewater were compared. The results showed that the best model wastewater, which represents the fouling trend of STE wastewater is the model wastewater whose composition is 15 mg/l of bovine serum albumin and 5.5 mg/l of dextran.The authors of this work wish to gratefully acknowledge the financial support from the Generalitat Valenciana through the program "Ayudas para la realizacion de proyectos I+D para grupos de investigacion emergentes GV/2013."Tora Grau, M.; Soler Cabezas, JL.; Vincent Vela, MC.; Mendoza Roca, JA.; Martínez Francisco, FJ. (2014). Comparison of different model solutions to simulate membrane fouling in the ultrafiltration of a secondary effluent from a municipal wastewater treatment plant. Desalination and Water Treatment. 1-7. https://doi.org/10.1080/19443994.2014.939865S17Delgado, S., Dı́az, F., Vera, L., Dı́az, R., & Elmaleh, S. (2004). Modelling hollow-fibre ultrafiltration of biologically treated wastewater with and without gas sparging. Journal of Membrane Science, 228(1), 55-63. doi:10.1016/j.memsci.2003.09.011Qin, J.-J., Oo, M. H., Lee, H., & Kolkman, R. (2004). Dead-end ultrafiltration for pretreatment of RO in reclamation of municipal wastewater effluent. Journal of Membrane Science, 243(1-2), 107-113. doi:10.1016/j.memsci.2004.06.010Konieczny, K. (1998). Disinfection of surface and ground waters with polymeric ultrafiltration membranes. Desalination, 119(1-3), 251-258. doi:10.1016/s0011-9164(98)00166-0Madaeni, S. S., Fane, A. G., & Grohmann, G. S. (1995). Virus removal from water and wastewater using membranes. Journal of Membrane Science, 102, 65-75. doi:10.1016/0376-7388(94)00252-tArnal Arnal, J. M., Sancho Fernández, M., Martín Verdú, G., & Lora García, J. (2001). Design of a membrane facility for water potabilization and its application to Third World countries. Desalination, 137(1-3), 63-69. doi:10.1016/s0011-9164(01)00205-3Arévalo, J., Garralón, G., Plaza, F., Moreno, B., Pérez, J., & Gómez, M. Á. (2009). Wastewater reuse after treatment by tertiary ultrafiltration and a membrane bioreactor (MBR): a comparative study. Desalination, 243(1-3), 32-41. doi:10.1016/j.desal.2008.04.013Katsoufidou, K., Yiantsios, S. G., & Karabelas, A. J. (2008). An experimental study of UF membrane fouling by humic acid and sodium alginate solutions: the effect of backwashing on flux recovery. Desalination, 220(1-3), 214-227. doi:10.1016/j.desal.2007.02.038Muthukumaran, S., Nguyen, D. A., & Baskaran, K. (2011). Performance evaluation of different ultrafiltration membranes for the reclamation and reuse of secondary effluent. Desalination, 279(1-3), 383-389. doi:10.1016/j.desal.2011.06.040Henderson, R. K., Subhi, N., Antony, A., Khan, S. J., Murphy, K. R., Leslie, G. L., … Le-Clech, P. (2011). Evaluation of effluent organic matter fouling in ultrafiltration treatment using advanced organic characterisation techniques. Journal of Membrane Science, 382(1-2), 50-59. doi:10.1016/j.memsci.2011.07.041Fan, L., Nguyen, T., Roddick, F. A., & Harris, J. L. (2008). Low-pressure membrane filtration of secondary effluent in water reuse: Pre-treatment for fouling reduction. Journal of Membrane Science, 320(1-2), 135-142. doi:10.1016/j.memsci.2008.03.058Xiao, D., Li, W., Chou, S., Wang, R., & Tang, C. Y. (2012). A modeling investigation on optimizing the design of forward osmosis hollow fiber modules. Journal of Membrane Science, 392-393, 76-87. doi:10.1016/j.memsci.2011.12.006Kaya, Y., Barlas, H., & Arayici, S. (2011). Evaluation of fouling mechanisms in the nanofiltration of solutions with high anionic and nonionic surfactant contents using a resistance-in-series model. Journal of Membrane Science, 367(1-2), 45-54. doi:10.1016/j.memsci.2010.10.037Yu, C.-H., Fang, L.-C., Lateef, S. K., Wu, C.-H., & Lin, C.-F. (2010). Enzymatic treatment for controlling irreversible membrane fouling in cross-flow humic acid-fed ultrafiltration. Journal of Hazardous Materials, 177(1-3), 1153-1158. doi:10.1016/j.jhazmat.2010.01.022Gao, W., Liang, H., Ma, J., Han, M., Chen, Z., Han, Z., & Li, G. (2011). Membrane fouling control in ultrafiltration technology for drinking water production: A review. Desalination, 272(1-3), 1-8. doi:10.1016/j.desal.2011.01.051Amin Saad, M. (2004). Early discovery of RO membrane fouling and real-time monitoring of plant performance for optimizing cost of water. Desalination, 165, 183-191. doi:10.1016/j.desal.2004.06.021Jayalakshmi, A., Rajesh, S., & Mohan, D. (2012). Fouling propensity and separation efficiency of epoxidated polyethersulfone incorporated cellulose acetate ultrafiltration membrane in the retention of proteins. Applied Surface Science, 258(24), 9770-9781. doi:10.1016/j.apsusc.2012.06.028Qu, F., Liang, H., Wang, Z., Wang, H., Yu, H., & Li, G. (2012). Ultrafiltration membrane fouling by extracellular organic matters (EOM) of Microcystis aeruginosa in stationary phase: Influences of interfacial characteristics of foulants and fouling mechanisms. Water Research, 46(5), 1490-1500. doi:10.1016/j.watres.2011.11.051Wang, C., Li, Q., Tang, H., Yan, D., Zhou, W., Xing, J., & Wan, Y. (2012). Membrane fouling mechanism in ultrafiltration of succinic acid fermentation broth. Bioresource Technology, 116, 366-371. doi:10.1016/j.biortech.2012.03.099Nataraj, S., Schomäcker, R., Kraume, M., Mishra, I. M., & Drews, A. (2008). Analyses of polysaccharide fouling mechanisms during crossflow membrane filtration. Journal of Membrane Science, 308(1-2), 152-161. doi:10.1016/j.memsci.2007.09.060Zator, M., Ferrando, M., López, F., & Güell, C. (2007). Membrane fouling characterization by confocal microscopy during filtration of BSA/dextran mixtures. Journal of Membrane Science, 301(1-2), 57-66. doi:10.1016/j.memsci.2007.05.038Xiao, K., Wang, X., Huang, X., Waite, T. D., & Wen, X. (2009). Analysis of polysaccharide, protein and humic acid retention by microfiltration membranes using Thomas’ dynamic adsorption model. Journal of Membrane Science, 342(1-2), 22-34. doi:10.1016/j.memsci.2009.06.016Nigam, M. O., Bansal, B., & Chen, X. D. (2008). Fouling and cleaning of whey protein concentrate fouled ultrafiltration membranes. Desalination, 218(1-3), 313-322. doi:10.1016/j.desal.2007.02.027MOUROUZIDISMOUROUZIS, S., & KARABELAS, A. (2006). Whey protein fouling of microfiltration ceramic membranes—Pressure effects. Journal of Membrane Science, 282(1-2), 124-132. doi:10.1016/j.memsci.2006.05.012Carić, M. Đ., Milanović, S. D., Krstić, D. M., & Tekić, M. N. (2000). Fouling of inorganic membranes by adsorption of whey proteins. Journal of Membrane Science, 165(1), 83-88. doi:10.1016/s0376-7388(99)00221-5Tasselli, F., Cassano, A., & Drioli, E. (2007). Ultrafiltration of kiwifruit juice using modified poly(ether ether ketone) hollow fibre membranes. Separation and Purification Technology, 57(1), 94-102. doi:10.1016/j.seppur.2007.03.007Hao, Y., Moriya, A., Maruyama, T., Ohmukai, Y., & Matsuyama, H. (2011). Effect of metal ions on humic acid fouling of hollow fiber ultrafiltration membrane. Journal of Membrane Science, 376(1-2), 247-253. doi:10.1016/j.memsci.2011.04.035Marcos, B., Moresoli, C., Skorepova, J., & Vaughan, B. (2009). CFD modeling of a transient hollow fiber ultrafiltration system for protein concentration. Journal of Membrane Science, 337(1-2), 136-144. doi:10.1016/j.memsci.2009.03.036Chung, T.-S., Qin, J.-J., & Gu, J. (2000). Effect of shear rate within the spinneret on morphology, separation performance and mechanical properties of ultrafiltration polyethersulfone hollow fiber membranes. Chemical Engineering Science, 55(6), 1077-1091. doi:10.1016/s0009-2509(99)00371-1Nguyen, T.-A., Yoshikawa, S., Karasu, K., & Ookawara, S. (2012). A simple combination model for filtrate flux in cross-flow ultrafiltration of protein suspension. Journal of Membrane Science, 403-404, 84-93. doi:10.1016/j.memsci.2012.02.026Domínguez Chabaliná, L., Rodríguez Pastor, M., & Rico, D. P. (2013). Characterization of soluble and bound EPS obtained from 2 submerged membrane bioreactors by 3D-EEM and HPSEC. Talanta, 115, 706-712. doi:10.1016/j.talanta.2013.05.062Viebke, C. (2000). Determination of molecular mass distribution of κ-carrageenan and xanthan using asymmetrical flow field-flow fractionation. Food Hydrocolloids, 14(3), 265-270. doi:10.1016/s0268-005x(99)00066-1Kelly, S. T., & Zydney, A. L. (1995). Mechanisms for BSA fouling during microfiltration. Journal of Membrane Science, 107(1-2), 115-127. doi:10.1016/0376-7388(95)00108-oHwang, K.-J., & Sz, P.-Y. (2011). 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    Fourier transform microwave spectroscopy of Ac-Ser-NH2: the role of side chain interactions in peptide folding

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    Serine capped dipeptide N-acetyl-L-serinamide (Ac-Ser-NH2) has been investigated using Fourier transform microwave spectroscopic techniques combined with laser ablation sources. Spectral signatures originating from one dominant species have been detected in the supersonic expansion. Rotational and nuclear quadrupole coupling constants of the two 14N nuclei have been used in the characterization of a Ceq/g-turn structure, which is stabilized by a C7O·· ·HN intramolecular hydrogen bond closing a seven-membered ring. Two extra hydrogen bonds involving the polar side chain (–CH2OH) further stabilize the structure. The non-observation of C5 species, attributed to the presence of the polar side chain, is in contrast with the previous gas phase observation of the related dipeptides containing glycine or alanine residues. The A–E splitting pattern arising from the internal rotation of the methyl group has been analyzed and the internal rotation barrier has been determined

    Effect of toothbrushing duration and dentifrice quantity on enamel remineralisation: An in situ randomized clinical trial

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    Objectives The influence of toothbrushing duration and dentifrice quantity on fluoride efficacy against dental caries is poorly understood. This study investigated effects of these two oral hygiene factors on enamel remineralisation (measured as surface microhardness recovery [SMHR]), enamel fluoride uptake (EFU), and net acid resistance (NAR) post-remineralisation in a randomized clinical study using an in situ caries model. Methods Subjects (n = 63) wore their partial dentures holding partially demineralised human enamel specimens and brushed twice-daily for two weeks, following each of five regimens: brushing for 120 or 45 s with 1.5 g of 1150 ppm F (as NaF) dentifrice; for 120 or 45 s with 0.5 g of this dentifrice; and for 120 s with 1.5 g of 250 ppm F (NaF) dentifrice. Results Comparing brushing for 120 s against brushing for 45 s, SMHR and EFU increased by 20.0% and 26.9% respectively when 1.5 g dentifrice was used; and by 22.8% and 19.9% respectively when 0.5 g dentifrice was used. Comparing brushing with 1.5 g against brushing with 0.5 g dentifrice, SMHR and EFU increased by 35.3% and 51.3% respectively when brushing for 120 s, and by 38.4% and 43.0% respectively when brushing for 45 s. Increasing brushing duration and dentifrice quantity also increased the NAR value. The effects of these two oral hygiene factors on SMHR, EFU, and NAR were statistically significant (p < 0.05 in all cases). Conclusion Brushing duration and dentifrice quantity have the potential to influence the anti-caries effectiveness of fluoride dentifrices. Study NCT01563172 on ClinicalTrials.gov. Clinical significance The effect of two key oral hygiene regimen factors – toothbrushing duration and dentifrice quantity – on fluoride’s anticaries effectiveness is unclear. This 2-week home-use in situ remineralisation clinical study showed both these factors can influence fluoride bioactivity, and so can potentially affect fluoride’s ability to protect against caries

    AT1 Receptor Gene Polymorphisms in relation to Postprandial Lipemia

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    Background. Recent data suggest that the renin-angiotensin system may be involved in triglyceride (TG) metabolism. We explored the effect of the common A1166C and C573T polymorphisms of the angiotensin II type 1 receptor (AT1R) gene on postprandial lipemia. Methods. Eighty-two subjects measured daytime capillary TG, and postprandial lipemia was estimated as incremental area under the TG curve. The C573T and A1166C polymorphisms of the AT1R gene were determined. Results. Postprandial lipemia was significantly higher in homozygous carriers of the 1166-C allele (9.39 ± 8.36 mM*h/L) compared to homozygous carriers of the 1166-A allele (2.02 ± 6.20 mM*h/L) (P < 0.05). Postprandial lipemia was similar for the different C573T polymorphisms. Conclusion. The 1166-C allele of the AT1R gene seems to be associated with increased postprandial lipemia. These data confirm the earlier described relationships between the renin-angiotensin axis and triglyceride metabolism
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