An off-shell I.R. regularization strategy in the analysis of collinear divergences

We present a method for the analysis of singularities of Feynman amplitudes based on the Speer sector decomposition of the Schwinger parametric integrals combined with the Mellin-Barnes transform. The sector decomposition method is described in some details. We suggest the idea of applying the method to the analysis of collinear singularities in inclusive QCD cross sections in the mass-less limit regularizing the forward amplitudes by an off-shell choice of the initial particle momenta. It is shown how the suggested strategy works in the well known case of the one loop corrections to Deep Inelastic Scattering.Comment: 25 pages, 3 figure

Human genetics and genomics meetings going virtual: practical lessons learned from two international meetings in early 2020

The recent coronavirus disease 2019 (COVID-19) pandemic has caused worldwide disruption which also extends to the arena of scientific meetings around the world. Here, we explore the lessons learned from moving two human genetics and genomics meetings quickly to an online format in early 2020. The tips presented herein may be useful not only for future virtual meetings but may also enrich future physical if not hybrid meetings once they resum

Changing the grazing session from morning to afternoon or including tannins in the diet was effective in decreasing the urinary nitrogen of dairy cows fed a total mixed ration and herbage

Our aim was to evaluate whether increasing soluble carbohydrates in the herbage by changing the time of the grazing session or including Acacia mearnsii tannin in the diet would affect intake, digestion, N partitioning, and productive performance of dairy cows fed a diet combining ryegrass herbage with partial total mixed ration (PMR). We hypothesized that both strategies could reduce the concentration of NH3-N in the rumen, reducing urinary N excretion. Nine Holstein cows were used in a triplicate 3 × 3 Latin square experiment with 3 experimental periods of 22 d. The cows were fed a fixed amount of PMR [60% of the predicted individual dry matter intake (DMI)], and an unrestricted amount of herbage in 1 grazing session of 5 h/d. The treatments were (1) morning grazing session and afternoon PMR meal (AM); (2) morning PMR meal and afternoon grazing session (PM); and (3) morning grazing session and afternoon PMR meal supplemented with 15.0 g of tannins/kg of PMR dry matter (TAN). Milk production was not affected by treatments. Although the protein concentration was lower for TAN than for PM, no differences were detected for the yield of any component between treatments. The concentration of individual or grouped fatty acids in milk fat was not affected by treatments, except for 16:1 cis-9 and Δ9-desaturase ratios 14:1/14:0 and 16:1/16:0, which were lower for TAN. Treatments did not affect total DMI, but PM tended to increase herbage DMI and reduce dry matter and crude protein digestibilities. Treatments did not affect cow eating and ruminating behavior except for the proportion of time spent eating PMR, which was higher for PM and TAN. Although no relevant effects of treatments on ruminal fermentation, purine derivatives excretion in urine, or N excretion in milk were detected, both PM and TAN decreased the total N excreted in urine by an average of 8% compared with AM. In conclusion, changing the grazing session from the morning to the afternoon and including tannins in the diet were effective in decreasing the excretion of urinary N but did not change the productive performance of dairy cows fed PMR and ryegrass herbage.Fil: Pozo, Claudio. Universidade Federal de Santa Maria; BrasilFil: Kozloski, Gilberto V.. Universidade Federal de Santa Maria; BrasilFil: Cuffia, Maira. Universidad Nacional del Litoral. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Repetto, José L.. Universidad de la República; UruguayFil: Cajarville, Cecilia. Universidad de la República; Urugua

Utilidad de los marcadores moleculares en el diagnóstico de nódulos tiroideos con citología indeterminada

Los nódulos tiroideos representan un problema clínico a nivel mundial debida a su alta prevalencia. La importancia clínica de su estudio radica en excluir malignidad, que ocurre entre el 7-15% de los mismos. El método estándar de oro para el diagnóstico de los mismos es el análisis citológico de la punción aspiración con aguja fina. Sin embargo, hasta un 30% de estos presentan citologías indeterminadas (Bethesda III o IV). Con un resultado histopatológico benigno en, aproximadamente tres de cada cuatro de estos casos, la cirugía diagnóstica (tiroidectomía parcial o lobectomía) resultaen un inconveniente ya que expone al paciente a innecesarios riesgos quirúrgicos. En el caso de lesiones malignas, una tiroidectomía en una segunda etapa es a menudo indicada, lo que se asocia con costos adicionales y mayores riesgos de complicaciones quirúrgicas. Es por esto que se requiere de una herramienta con mayor precisión para determinar la benignidad o malignidad de un nódulo tiroideo con citología indeterminada. En este contexto el análisis molecular del tejido tiroideo se convierte en un poderoso complemento para el diagnóstico preoperatorio de los nódulos tiroideos con citología indeterminada, ya que entre el 60 al 70% de los cánceres de tiroides albergan al menos una mutación genética conocida.Thyroid nodules represent a clinical problem worldwide due to its high prevalence. The clinical importance lies in excluding malignancy, which occurs between 7-15% of them. The cytological analysis is the gold standard for the diagnosis. However, up to 30% of these have indeterminate cytologies (Bethesda III or IV). In these patients, diagnostic surgeries are performed. With a benign histopathological result in approximately three out of four of these cases, surgery results in an inconvenience since it exposes the patient to unnecessary surgical risks. In the case of malignant lesions, a thyroidectomy in a second stage is often indicated, which is associated with additional costs and increased risks of surgical complications. A more precise method is needed to determine the benignity or malignancy of a thyroid nodule with indeterminate cytology. In this context, molecular analysis of thyroid tissue becomes a powerful complement for the preoperative diagnosis of thyroid nodules with indeterminate cytology, since between 60 to 70% of thyroid cancers harbor at least one known genetic mutation.Fil: Ricci, V.. Sociedad Argentina de Endocrinología y Metabolismo; ArgentinaFil: Repetto, Esteban Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Bioquímica Clínica; Argentin

A deep-learning sequence-based method to predict protein stability changes upon genetic variations

Several studies have linked disruptions of protein stability and its normal functions to disease. Therefore, during the last few decades, many tools have been developed to predict the free energy changes upon protein residue variations. Most of these methods require both sequence and structure information to obtain reliable predictions. However, the lower number of protein structures available with respect to their sequences, due to experimental issues, drastically limits the application of these tools. In addition, current methodologies ignore the antisymmetric property characterizing the thermodynamics of the protein stability: a variation from wild-type to a mutated form of the protein structure (XW→XM) and its reverse process (XM→XW) must have opposite values of the free energy difference (ΔΔGWM=−ΔΔGMW). Here we propose ACDC-NN-Seq, a deep neural network system that exploits the sequence information and is able to incorporate into its architecture the antisymmetry property. To our knowledge, this is the first convolutional neural network to predict protein stability changes relying solely on the protein sequence. We show that ACDC-NN-Seq compares favorably with the existing sequence-based methods

Magnetic loss analysis in coaxial magnetic gears

This paper proposes a procedure for computing magnetic losses in coaxial magnetic gears. These magnetic structures are made of permanent magnets and ferromagnetic poles in relative motion transferring torque between two shafts in a contactless way. The loss computation in magnetic materials is crucial to define the system performance. The flux distribution inside the iron parts is computed by means of the finite element method and a model of iron losses taking into account the rotational nature of the flux loci is applied. The procedure highlights where the major loss sources are present and gives the opportunity to evaluate some corrective measures to reduce their effects. Particular attention is devoted to the 2D modeling in presence of permanent magnets segmentatio

Once-daily intrapleural urokinase treatment of complicated parapneumonic effusion in pediatric patients

In this paper, we describe our experience in the treatment of childhood empyema using urokinase. Patients' ages ranged from 2 to 12 years. Urokinase (dosage: 3,100 IU/kg/day) was diluted in normal saline to produce 1000 IU/ml (maximum dosage 100,000 IU in 100 ml of normal saline). After 2 hours, the clamped catheters were released and connected to water-seal suction at a negative pressure of 10 cm H2O. Pleural irrigations were continued once a day until thoracostomy tube output decreased to less than 10 ml/day (urokinase treatment mean duration: 11.5 days). The complete resolution of the chest effusion was assessed on chest ultrasound scan and radiographs. None of the patients experienced any side effects due to urokinase. It would now seem reasonable to advocate small chest tube thoracostomy and intrapleural urokinase as first-line treatment of pleural empyema in children, with surgery indicated as a secondaryintervention