70 research outputs found
Simulation of the production of fructooligosaccharides
Introduction: Fructooligosaccharides (FOS) are considered bothalimentary additives and nutraceutics. Several studies have demonstratedtheir prebiotic properties. A simulation of FOS productionwas made. Kinetics parameters of FOS growth and synthesiswere studied.Objective: The objective of this work was to simulate FOS productionin several initial conditions using a mathematical modeldeveloped by the authors.Materials and Methods: Experimental data were obtained usingthe strain Aureobasidium sp. The bioproduction conditions and thedetails of the model were previously reported by the authors. Thesoftware used for the simulation was Matlab 7.Results and Conclusions: The simulation shows the relationshipbetween the sugars at different initial concentrations. Sucrose rapidlydisappears, enabling FOS and glucose formation. An increase insucrose concentration resulted in an increase in FOS production. Thiswill contribute to the study of the production of this prebiotic.Fil: Salinas, Martín Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Perotti, Nora Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaXXIV Annual Scientific Meeting Tucuman Biology AssociationTafi del ValleArgentinaAsociación de Biología de Tucumá
Influence of Kaolinite Clay Supplementation on Growth Performance and Digestive Function in Finishing Calf-fed Holstein Steers.
Two experiments were conducted to examine the influence of kaolinite clay supplementation (0%, 1%, or 2% diet dry matter [DM] basis) on characteristics of digestion (Trial 1) and growth performance (Trial 2) in calf-fed Holstein steers fed a finishing diet. In Trial 1, 6 Holstein steers (539±15 kg) with ruminal and duodenal cannulas were used to evaluate treatment effects on characteristics of digestion. Kaolinite clay supplementation decreased total tract DM digestion (linear effect, p<0.01) without effects (p≥0.10) on site and extent of digestion of organic matter, neutral detergent fiber, starch and N, or ruminal microbial efficiency. There were no treatment effects on ruminal pH, volatile fatty acids molar proportions or estimated methane production. In Trial 2, 108 Holstein steers (132.4±5.6 kg) were used in a 308-d study to evaluate growth performance and carcass characteristics. There were no treatment effects (p>0.10) on average daily gain (ADG) and gain efficiency (ADG/dry matter intake). Kaolinite supplementation tended (linear effect, p = 0.08) to increase dietary net energy (NE) during the initial 112-d period. However, the overall (308-d) effect of supplementation dietary NE was not appreciable (p>0.20). However, due to the inertness of kaolinite, itself, the ratio of observed-to-expected dietary NE increased with kaolinite supplementation. This effect was more pronounced (linear effect, p 0.03) during the initial 224 d of the study. Overall (308 d), kaolinite supplementation tended to increase (linear effect, p = 0.07) dietary NE by 3% over expected. Kaolinite supplementation did not affect carcass weight, yield grade, longissimus area, kidney, pelvic and heart fat, and quality grade, but decreased (linear effect, p = 0.01) dressing percentage. It is concluded that kaolinite supplementation up to 2% of diet DM may enhance energetic efficiency of calf-fed Holstein steers in a manner independent of changes in characteristics of ruminal and total tract digestion
Análisis del control previo aplicado a los contratos de interconexión de redes y servicios públicos de telecomunicaciones en el Perú.
La presente tesis identifica que la interconexión de redes y servicios públicos de
telecomunicaciones se encuentra sujeta a la regulación económica, principalmente,
por la cualidad de la interconexión de permitir que los usuarios de los servicios
públicos de telecomunicaciones se puedan comunicar entre sí.
La regulación de los contratos de interconexión se ha concentrado en establecer el
control previo de los mismos antes de que surtan efectos entre las partes y respecto
de terceros. Este control previo es un método regulatorio que implica la actuación del
Estado, a través de una autoridad administrativa especializada como el Organismo
Supervisor de la Inversión Privada en Telecomunicaciones - OSIPTEL, para aprobar
previamente si el contrato de interconexión se adecua al marco legal, a los criterios de
costos y no perjudica a terceros operadores o a los usuarios en general.
El control previo implica una intervención intensa y por ello, su establecimiento debe
estar fundamentado en la protección del interés público, los costos de su aplicación
deben ser menores que los beneficios y deben existir criterios objetivos y un ámbito de
aplicación claros.
El control previo se inició en un escenario de apertura del mercado y se mantiene
hasta la fecha, en la que existe un nivel mayor de competencia, apertura y dinamismo
en el mercado de servicios públicos de telecomunicaciones en el país.
En ese sentido, la presente tesis presenta el marco teórico del control previo y enfatiza
en la necesidad de que este control requiere tener mayor claridad en su aplicación y
justificación para evitar que los costos de su aplicación sean mayores a los beneficios,
y en consecuencia, pueda ser perjudicial a la sociedad. Asimismo, se presenta una
evaluación del control previo aplicado a la legislación peruana sobre la materia y se
presenta una propuesta de revisión de la problemática.Tesi
Centrality dependence of photon yield and elliptic flow from gluon fusion and splitting induced by magnetic fields in relativistic heavy-ion collisions
We compute the photon yield and elliptic flow coefficient in relativistic
heavy-ion collisions from gluon fusion and splitting processes induced by a
magnetic field for different centralities. The calculation accounts for the
intense magnetic field and the high gluon occupation number at early times. The
photon production induced by these process represents an excess contribution
over calculations without magnetic field effects. We compare this excess to the
difference between PHENIX data and recent hydrodynamic calculations for the
photon transverse momentum distribution and elliptic flow coefficient .
The time evolution of the field strength and reaction volume is computed using
UrQMD. We show that with reasonable values for the saturation scale, the
calculation helps to better describe the experimental results obtained at RHIC
energies for the lowest part of the transverse photon momentum at different
centralities.Comment: Expanded discussion. Version to appear in The European Physical
Journal
Detection transposable elements in Botrytis cinerea in latent infection stage from symptomless apples
Detection of Botrytis cinerea latent infections on apples before storage is essential for effective control strategies in the fruit postharvest industry. In the present study a PCR detection method, based on primers designed on B. cinerea transposable elements (boty and flipper) and intergenic spacer (IGS) region as internal control were utilized to reveal the presence of symptomless infections on apple fruits. The method molecular proved to be highly specific and sensitive in detecting latent infections, revealed the presence of the pathogen in 83% of the samples from infected apples with 104 conidia/mL, whereas those infected with 106 conidia/mL detected 94% as compared to the traditional method that revealed the pathogen in 40 and 66% of the samples inoculated with 104 and 106 conidia/mL respectively. Furthermore, the method characterized B. cinerea as subpopulation transposa-type by the presence of the transposable elements boty and flipper The results obtained of DNA quantification method were compared with ELISA assay and these studies showed good correlation. Therefore our method has important advantages compared with others detection methods for B. cinerea, because the proposed methodology allowed distinguishes between its two subpopulations (vacuma and transposa) and this would allow establish possible control appropriate strategies. Finally, the method can be an interesting alternative for its possible application in the phytosanitary programs of the fruit industry worldwide.Fil: Fernández, Jorge Gastón. Universidad Nacional de San Luis. Facultad de Quimica, Bioquimica y Farmacia. Departamento de Quimica. Area de Quimica Analitica; ArgentinaFil: Fernández Baldo, Martín Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto de Química de San Luis; ArgentinaFil: Muñoz, Claudio Javier. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Cuyo Mendoza - San Juan. Estación Experimental Agropecuaria Mendoza; ArgentinaFil: Salinas, Eloy. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Raba, Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto de Química de San Luis; ArgentinaFil: Sanz Ferramola, Maria Isabel. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto de Química de San Luis; Argentin
Escenarios de guerra: paseando por Madrid a través de su memoria
Este libro difunde los resultados de las investigaciones llevadas a cabo en distintos proyectos de investigación en los últimos años, presentados en la Semana de la Ciencia y la Tecnología de Madrid. En él se proponen tres itinerarios por los lugares más significativos del impacto de la Guerra Civil en Madrid que recogen aspectos de la historia, el arte, el patrimonio, la memoria y la vida cotidiana, apoyándose en las fuentes directas de quienes vivieron el conflicto
Impacto de la pandemia de la COVID-19 en el funcionamiento de un servicio público de Ortopedia y Traumatología: nuestro aprendizaje luego de la primera ola
Introducción: El objetivo principal fue comparar la actividad clínico-quirúrgica de nuestro Servicio de Ortopedia y Traumatología antes de la instauración del plan de contingencia frente a la pandemia de la COVID-19 y durante este, un aspecto relevante para establecer antecedentes que permitan guiar nuestro desempeño ante la segunda ola de casos y futuras contingencias semejantes.
Materiales y Métodos: Estudio analítico observacional longitudinal ambispectivo de los pacientes atendidos en el Servicio de Ortopedia y Traumatología de un hospital del sistema público de la Ciudad Autónoma de Buenos Aires, durante el plan de contingencia frente a la pandemia COVID-19. Como variable de resultado primaria se valoró el número total de cirugías realizadas durante el período de estudio.
Resultados: La pandemia se asoció con menos cirugías totales (p = 0,002), de Guardia (p = 0,000) y de Planta (p = 0,002). Las cirugías totales se redujeron un 81,5%. Las cirugías de urgencia representaron el 97%, diferencia significativa con el período fuera de la pandemia (p = 0,080). Además, el promedio de cirugías por día quirúrgico disponible fue significativamente menor (p = 0,000).
Conclusiones: Creemos que la atención de la enfermedad ortopédica y el trauma musculoesquelético, adaptada a las obligaciones indicadas por el plan nacional y regional de contingencia frente a la pandemia, fue notoriamente menor a nuestro desempeño habitual. Si bien respondimos adecuadamente a las urgencias de nuestra especialidad queda pendiente la posibilidad de estratificar y considerar tipos de pacientes con cuadros pasibles de ser tratados, en forma gradual, durante la pandemia
Pancreatic metastases from renal cell carcinoma. Postoperative outcome after surgical treatment in a Spanish multicenter study (PANMEKID)
Background: Renal Cell Carcinoma (RCC) occasionally spreads to the pancreas. The purpose of our study is to evaluate the short and long-term results of a multicenter series in order to determine the effect of surgical treatment on the prognosis of these patients. Methods: Multicenter retrospective study of patients undergoing surgery for RCC pancreatic metastases, from January 2010 to May 2020. Variables related to the primary tumor, demographics, clinical characteristics of metastasis, location in the pancreas, type of pancreatic resection performed and data on short and long-term evolution after pancreatic resection were collected. Results: The study included 116 patients. The mean time between nephrectomy and pancreatic metastases' resection was 87.35 months (ICR: 1.51-332.55). Distal pancreatectomy was the most performed technique employed (50 %). Postoperative morbidity was observed in 60.9 % of cases (Clavien-Dindo greater than IIIa in 14 %). The median follow-up time was 43 months (13-78). Overall survival (OS) rates at 1, 3, and 5 years were 96 %, 88 %, and 83 %, respectively. The disease-free survival (DFS) rate at 1, 3, and 5 years was 73 %, 49 %, and 35 %, respectively. Significant prognostic factors of relapse were a disease free interval of less than 10 years (2.05 [1.13-3.72], p 0.02) and a history of previous extrapancreatic metastasis (2.44 [1.22-4.86], p 0.01). Conclusions: Pancreatic resection if metastatic RCC is found in the pancreas is warranted to achieve higher overall survival and disease-free survival, even if extrapancreatic metastases were previously removed. The existence of intrapancreatic multifocal compromise does not always warrant the performance of a total pancreatectomy in order to improve survival. (C) 2021 The Authors. Published by Elsevier Ltd
Repeated pancreatic resection for pancreatic metastases from renal cell Carcinoma: A Spanish multicenter study (PANMEKID)
Background and objectives: Recurrent isolated pancreatic metastasis from Renal Cell Carcinoma (RCC) after pancreatic resection is rare. The purpose of our study is to describe a series of cases of relapse of pancreatic metastasis from renal cancer in the pancreatic remnant and its surgical treatment with a repeated pancreatic resection, and to analyse the results of both overall and disease -free survival. Methods: Multicenter retrospective study of patients undergoing pancreatic resection for RCC pancreatic metastases, from January 2010 to May 2020. Patients were grouped into two groups depending on whether they received a single pancreatic resection (SPS) or iterative pancreatic resection. Data on short and long-term outcome after pancreatic resection were collected. Results: The study included 131 pancreatic resections performed in 116 patients. Thus, iterative pancreatic surgery (IPS) was performed in 15 patients. The mean length of time between the first pancreatic surgery and the second was 48.9 months (95 % CI: 22.2-56.9). There were no differences in the rate of postoperative complications. The DFS rates at 1, 3 and 5 years were 86 %, 78 % and 78 % vs 75 %, 50 % and 37 % in the IPS and SPS group respectively (p = 0.179). OS rates at 1, 3, 5 and 7 years were 100 %, 100 %, 100 % and 75 % in the IPS group vs 95 %, 85 %, 80 % and 68 % in the SPS group (p = 0.895). Conclusion: Repeated pancreatic resection in case of relapse of pancreatic metastasis of RCC in the pancreatic remnant is justified, since it achieves OS results similar to those obtained after the first resection
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