2,366 research outputs found
Next-to-leading order effects on the lightest scalar tetraquark mass estimates using QCD Laplace sum-rules
Multiquark states have been of great interest among hadronic physicists, and despite the big breakthrough that came in 2003 with the discovery of the charmonium-like tetraquark candidate X(3872), their structure and masses are still eclipsed by theoretical uncertainties in the precision of the calculations. The study of tetraquarks can give us another insight to understand strong interactions at the elementary level and at different energy scales. The goal of this research is to explore light-quark tetraquark structures and estimate their masses using the QCD sum-rules approach. The specific focus is on the controversial light scalar tetraquark Ï (denoted as f0(500) in the Particle Data Group classification scheme), and the contributions from next-to-leading order (NLO) diagrams to the spectral functions are incorporated in the process of finding a Borel window for a reliable sum-rule analysis. After a deep examination, this thesis includes analyses in terms of a single and a double resonance models, where the heavier state (980 MeV) used is the scalar f0(980). The results showed that the NLO terms play a significant role in the spectral function picture with contributions of up to 74% with respect to the leading-order (LO) perturbative terms, but their effects are suppressed in ratios used within the Laplace sum-rules scheme. Moreover, the key improvement is that NLO corrections benefit substantially the methodology by locating a suitable physical Borel window where the mass prediction range is reliable and result in the Ï mass prediction around 0.52 GeV < mÏ < 0.69 GeV. It was also found that the relative strength of the f0(980) coupling to the current is approximately three to four times stronger than the Ï, such results are in agreement with chiral Lagrangian determinations, hence in accordance with the tetraquark scheme
Urbanization, socio-economic changes and population growth in Brazil: dietary shifts and environmental implications.
Population growth, economic globalization, improving living standards and urbanization are causing important changes in the global food system and modifying the dietary habits in many parts of the world (Molden, 2007; Godfray et al., 2010). The nutritional transition (linked to the development of countries and the increasing wealth of its population) implies a shift away from traditional staple food such as roots and tuber vegetables and a rise in consumption of meat and milk products, refined and processed foods, as well as sugars, oils and fats (Ambler-Edwards et al., 2009). The contemporary food system puts significant pressure on natural resources, especially on land and water, because the growing food demand pushes the agricultural frontier beyond, causing large impacts on ecosystems (Ambler-Edwards et al. 2009: 11-18). Also, the trend towards richer diets in animal proteins and processed food adds further pressure on the environment, since it requires larger amount of water and land to be produced (Allan, 2011; Mekonnen and Hoekstra, 2012)
Island plants with newly discovered reproductive traits have higher capacity for uniparental reproduction, supporting Bakerâs law
Uniparental reproduction is advantageous when lack of mates limits outcrossing opportunities in plants. Bakerâs law predicts an enrichment of uniparental reproduction in habitats colonized via long-distance dispersal, such as volcanic islands. To test it, we analyzed reproductive traits at multiple hierarchical levels and compared seed-set after selfing and crossing experiments in both island and mainland populations of Limonium lobatum, a widespread species that Baker assumed to be self-incompatible because it had been described as pollen-stigma dimorphic, i.e., characterized by floral morphs differing in pollen-surface morphology and stigma-papillae shape that are typically self-incompatible. We discovered new types and combinations of pollen and stigma traits hitherto unknown in the literature on pollen-stigma dimorphism and a lack of correspondence between such combinations and pollen compatibility. Contrary to previous reports, we conclude that Limonium lobatum comprises both self-compatible and self-incompatible plants characterized by both known and previously undescribed combinations of reproductive traits. Most importantly, plants with novel combinations are overrepresented on islands, selfed seed-set is higher in islands than the mainland, and insular plants with novel pollen-stigma trait-combinations disproportionally contribute to uniparental reproduction on islands. Our results thus support Bakerâs law, connecting research on reproductive and island biology
Evolution of the SPATULA/ALCATRAZ gene lineage and expression analyses in the basal eudicot, Bocconia frutescens L. (Papaveraceae)
Abstract Background SPATULA (SPT) and ALCATRAZ (ALC) are recent paralogs that belong to the large bHLH transcription factor family. Orthologs of these genes have been found in all core eudicots, whereas pre-duplication genes, named paleoSPATULA/ALCATRAZ, have been found in basal eudicots, monocots, basal angiosperms and gymnosperms. Nevertheless, functional studies have only been performed in Arabidopsis thaliana, where SPT and ALC are partially redundant in carpel and valve margin development and ALC has a unique role in the dehiscence zone. Further analyses of pre-duplication genes are necessary to assess the functional evolution of this gene lineage. Results We isolated additional paleoSPT/ALC genes from Aristolochia fimbriata, Bocconia frutescens, Cattleya trianae and Hypoxis decumbens from our transcriptome libraries and performed phylogenetic analyses. We identified the previously described bHLH domain in all analyzed sequences and also new conserved motifs using the MEME suite. Finally, we analyzed the expression of three paleoSPT/ALC genes (BofrSPT1/2/3) from Bocconia frutescens, a basal eudicot in the Papaveraceae. To determine the developmental stages at which these genes were expressed, pre- and post-anthesis carpels and fruits of B. frutescens were collected, sectioned, stained, and examined using light microscopy. Using in situ hybridization we detected that BofrSPT1/2/3 genes are expressed in floral buds, early sepal initiation, stamens and carpel primordia and later during fruit development in the dehiscence zone of the opercular fruit. Conclusions Our expression results, in comparison with those available for core eudicots, suggest conserved roles of members of the SPT/ALC gene lineage across eudicots in the specification of carpel margins and the dehiscence zone of the mature fruits. Although there is some redundancy between ALC and SPT, these gene clades seem to have undergone some degree of sub-functionalization in the core eudicots, likely by changes in cis regulatory regions and to some extent in coding sequences, at least in Brassicaceae. Our results also indicate that in Bocconia frutescens, paleoSPT/ALC genes may play a role in early floral organ specification that was subsequently lost in core eudicot lineages
La Corte constitucional y las familias de parejas del mismo sexo en Colombia
El presente trabajo ofrece un estudio de la jurisprudencia constitucional que existe sobre el reconocimiento y protecciĂłn de los derechos de las parejas del mismo sexo. Se analizan las instituciones jurĂdicas determinantes para ese reconocimiento y se expone el limbo jurĂdico actual en el que se encuentran este tipo de parejas. Bajo ese contexto tambiĂ©n se utiliza la teorĂa jurĂdica y polĂtica de Ronald Dworkin con la finalidad de analizar los lĂmites y el ejercicio de la funciĂłn jurisdiccional de la Corte Constitucional, como garante de derechos y las implicaciones de Ă©sta en Colombia como Estado de Derecho democrĂĄtico, liberal y pluralista.Abogado (a)Pregrad
Pseudoarthrosis of second metatarsal fracture
Metatarsal fractures make up the greatest portion of foot fractures in children. Most of them are treated with closed reduction and non-weightbearing cast immobilization.Usually, these fractures heal uneventfully and delay union and pseudoarthrosis are rare. We report a case of a 10-year-old child with non-union of the second metatarsal following a traumatic fracture, caused by an accident 10 months before, and treated successfully by osteosynthesis with plate and screws. Good clinical outcome was achieved at 2 years follow-up
A 100-Year Review: Advances in goat milk research
In the century of research chronicled between 1917 and 2017, dairy goats have gone from simply serving as surrogates to cows to serving as transgenic carriers of human enzymes. Goat milk has been an important part of human nutrition for millennia, in part because of the greater similarity of goat milk to human milk, softer curd formation, higher proportion of small milk fat globules, and different allergenic properties compared with cow milk; however, key nutritional deficiencies limit its suitability for infants. Great attention has been given not only to protein differences between goat and cow milk, but also to fat and enzyme differences, and their effect on the physical and sensory properties of goat milk and milk products. Physiological differences between the species necessitate different techniques for analysis of somatic cell counts, which are naturally higher in goat milk. The high value of goat milk throughout the world has generated a need for a variety of techniques to detect adulteration of goat milk products with cow milk. Advances in all of these areas have been largely documented in the Journal of Dairy Science (JDS), and this review summarizes such advances
IgA anti-Actin antibodies in children with celiac disease: comparison of immunofluorescence with Elisa assay in predicting severe intestinal damage
<p>Abstract</p> <p>Background</p> <p>Previous studies have demonstrated that the presence of serum IgA antibodies against actin filaments (AAA) in patients with celiac disease (CD) is strongly associated with mucosal damage and severe degrees of villous atrophy.</p> <p>The aims of the present study were (1) to verify the effectiveness of IgA-AAA in newly diagnosed CD patients in a clinical setting (2) to compare the immunofluorescence assay with ELISA assay; (3) to compare the correlation of our IgA anti-tissue transglutaminase antibodies (tTG-Ab) class with mucosal intestinal lesions.</p> <p>Methods</p> <p>90 patients underwent endoscopy and multiple biopsies for suspected CD on the basis of symptoms, in presence of positive tTG-Ab tests. Twenty biopsied and 25 not-biopsied subjects with negative tTG-Ab were tested as control groups.</p> <p>IgA-AAA assays were performed by indirect immunofluorescence using rat epithelial intestinal cells, and by ELISA with a commercial kit. tTG-Ab assay was a radio-binding assay.</p> <p>Intestinal specimens were collected by upper endoscopy and the histological study was done according to the Marsh's classification modified by Oberhuber (M/O). Auto-antibodies assays and histological evaluation have been performed blindly by skilled operators.</p> <p>Results</p> <p>CD diagnosis was confirmed in 82 patients (type I M/O in 2 patients, IIIA in 18 patients, IIIB in 29 patients and IIIC in 33 patients). Two patients with type 1 lesion in presence of positive tTG-Ab and abdominal complaints, started a gluten free diet.</p> <p>The rate of IgA-AAA positivity (sensitivity) by IFI and ELISA in histologically proven celiac disease patients, were 5.5% and 25% patients in IIIA, 27.5% and 34.4% patients in IIIB, 78.8% and 75% in IIIC patients, respectively.</p> <p>Patients with normal or nearly normal mucosa, regardless of tTG-Ab status, presented negative IgA-AAA IFI assay. On the other hand, 1 patient with normal mucosa but positive tTG-Ab, also presented positive IgA-AAA ELISA. All healthy non biopsied controls had negative IgA-AAA. tTG-Ab serum concentration was significantly correlated with more severe intestinal lesion (IIIB, IIIC M/O).</p> <p>Conclusions</p> <p>IgA-AAA may be undetectable in presence of severe mucosal damage. Histology is still necessary to diagnose celiac disease and IgA-AAA cannot be included in usual screening tests, because it has little to offer if compared to the well-established tTG-Ab.</p> <p>IgA-AAA could be an adjunctive, very useful tool to support the diagnosis of CD in case of suboptimal histology, when the biopsy is to be avoided for clinical reasons, or in case of negative parents' consensus.</p
Optimization of continuous arsenic biosorption present in natural contaminated groundwater
BACKGROUND: Arsenic (As) is a serious water pollution problem in the world. In Argentina, it is related to old volcanic activities; for example, the western region of Santa Fe State has concentrations higher than 0.1 mgAs L â1 . In this work, a green, sensitive method was used to determine As concentration, and its removal using chitosan in bed columns was studied. Mathematical models were used to explain sorption, and the process was optimized using statistical methods. RESULTS: Arsenic quantification was realized with a bespoke modification of the As molybdenum blue method (detection limit = 0.0048 mg L â1 , quantification limit = 0.0145 mg L â1 ). Chitosan molar mass, pH ZPC and deacetylation degree were 350 ± 10 kDa, 6.3% and 76.2%, respectively. A maximum of 68.5% was obtained for As(V) removal at optimum conditions. Raising the bed column height produced an increment in breakthrough times, and the sorption process was favoured using low flow rates. Salinity, phosphate and nitrate concentration reductions were 60%, 50% and 70%, respectively. CONCLUSIONS: Sorption studies have been carried out on groundwater, using columns packed with chitosan for arsenic removal. The process was optimized by a factorial design. Elution profiles were adjusted adequately with mathematical models. The modified analytical technique for arsenic quantification applied in groundwater, was successful.Fil: Perez Mora, Barbara Edith. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Rosario. Instituto de QuĂmica Rosario. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂmicas y FarmacĂ©uticas. Instituto de QuĂmica Rosario; ArgentinaFil: BellĂș, SebastiĂĄn Eduardo. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Rosario. Instituto de QuĂmica Rosario. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂmicas y FarmacĂ©uticas. Instituto de QuĂmica Rosario; ArgentinaFil: Mangiameli, MarĂa Florencia. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Rosario. Instituto de QuĂmica Rosario. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂmicas y FarmacĂ©uticas. Instituto de QuĂmica Rosario; ArgentinaFil: GarcĂa, Silvia Isabel. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Rosario. Instituto de QuĂmica Rosario. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂmicas y FarmacĂ©uticas. Instituto de QuĂmica Rosario; ArgentinaFil: GonzĂĄlez, Juan Carlos. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Rosario. Instituto de QuĂmica Rosario. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂmicas y FarmacĂ©uticas. Instituto de QuĂmica Rosario; Argentin
Batch and fixed-bed column studies of selenite removal from contaminated water by orange peel-based sorbent
Orange peel is a biomass derived from citrus processing with desirable properties for metal sorption. In recent years, orange peel has been used to remove various heavy metals and toxic oxyanions. Selenium (Se) is an essential trace element for mammals. However, when the concentration of selenium exceeds an umbral limit, it becomes toxic. In this study, orange peel was used to treat Se(IV)-contaminated water. A high sorption capacity of 32.5 mg/g was obtained at the temperature of 20ÂșC and a pH of 2.0. Hydroxyl groups took actions to bind Se(IV) to the surface of the orange peel. The sorption process was spontaneous and endothermic. A chemical sorption mechanism was involved in the removal of Se(IV). The Thomas and modified dose-response models were used to simulate the experimental breakthrough curves. The bed depth service time model was used to calculate the critical bed depth ( Z0 ), and the calculated Z0 value was 1.6 cm. This study reveals that orange peel is a useful sorbent for Se(IV), and it is appropriate for the purification of Se(IV)-contaminated water.Fil: Perez Mora, Barbara Edith. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Rosario. Instituto de QuĂmica Rosario. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂmicas y FarmacĂ©uticas. Instituto de QuĂmica Rosario; ArgentinaFil: Bertoni, Fernando Ariel. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Rosario. Instituto de QuĂmica Rosario. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂmicas y FarmacĂ©uticas. Instituto de QuĂmica Rosario; ArgentinaFil: Mangiameli, MarĂa Florencia. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Rosario. Instituto de QuĂmica Rosario. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂmicas y FarmacĂ©uticas. Instituto de QuĂmica Rosario; ArgentinaFil: GonzĂĄlez, Juan Carlos. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Rosario. Instituto de QuĂmica Rosario. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂmicas y FarmacĂ©uticas. Instituto de QuĂmica Rosario; ArgentinaFil: BellĂș, SebastiĂĄn Eduardo. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Rosario. Instituto de QuĂmica Rosario. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂmicas y FarmacĂ©uticas. Instituto de QuĂmica Rosario; Argentin
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