Energy partition and segregation for an intruder in a vibrated granular system under gravity

The difference of temperatures between an impurity and the surrounding gas in an open vibrated granular system is studied. It is shown that, in spite of the high inhomogeneity of the state, the temperature ratio remains constant in the bulk of the system. The lack of energy equipartition is associated to the change of sign of the pressure diffusion coefficient for the impurity at certain values of the parameters of the system, leading to a segregation criterium. The theoretical predictions are consistent with previous experimental results, and also in agreement with molecular dynamics simulation results reported in this paper.Comment: To appear in Phys. Rev. Let

Symmetry breaking and clustering in a vibrated granular gas with several macroscopically connected compartments

The spontaneous symmetry breaking in a vibro-fluidized low-density granular gas in three connected compartments is investigated. When the total number of particles in the system becomes large enough, particles distribute themselves unequally among the three compartments. Particles tend to concentrate in one of the compartments, the other two having the (relatively small) same average number of particles. A hydrodynamical model that accurately predicts the bifurcation diagram of the system is presented. The theory can be easily extended to the case of an arbitrary number of connected compartments

RanBP2-Mediated SUMOylation Promotes Human DNA Polymerase Lambda Nuclear Localization and DNA Repair

Cellular DNA is under constant attack by a wide variety of agents, both endogenous and exogenous. To counteract DNA damage, human cells have a large collection of DNA repair factors. Among them, DNA polymerase lambda (Polλ) stands out for its versatility, as it participates in different DNA repair and damage tolerance pathways in which gap-filling DNA synthesis is required. In this work we show that human Polλ is conjugated with Small Ubiquitin-like MOdifier (SUMO) proteins both in vitro and in vivo, with Lys27 being the main target of this covalent modification. Polλ SUMOylation takes place in the nuclear pore complex and is mediated by the E3 ligase RanBP2. This post-translational modification promotes Polλ entry into the nucleus, which is required for its recruitment to DNA lesions and stimulated by DNA damage induction. Our work represents an advance in the knowledge of molecular pathways that regulate cellular localization of human Polλ, which are essential to be able to perform its functions during repair of nuclear DNA, and that might constitute an important point for the modulation of its activity in human cells

Intravenous lidocaine infusion for the treatment of acute pain in the pediatric intensive care unit: case series

Introducción:El uso de la infusión de lidocaína endovenosa ha aumentado en la última década como parte de un enfoque analgésico multimodal en los adultos; sin embargo, se dispone de información limitada sobre su seguridad y tolerabilidad en la población pediátrica. Métodos: Se presentan once casos de manejo de dolor agudo con lidocaína en infusión tratados en unidad de cuidado intensivo pediátrico. Resultados: Cinco casos fueron postoperatorio abdominal y seis casos tenían dolor abdominal no postoperatorio. Dos pacientes tenían cáncer y cursaban con colitis neutropénica. El control analgésico alcanzado fue bueno. Conclusión: Las infusiones de lidocaína parecen ser una opción segura para el manejo del dolor agudo ya sea posquirúrgico o no en la población pediátrica.Introduction: The use of intravenous lidocaine infusion has increased over the past decade as part of a multimodal approach to analgesia in adults; however, information about its safety and tolerability in the pediatric population is limited. Methods: Acute pain management using lidocaine infusion in eleven patients treated in the pediatric intensive care unit. Results: Five cases of postoperative abdominal pain and six cases of non-operative abdominal pain. Two cases were cancer patients affected by neutropenic colitis. Analgesic control achieved was good. Conclusion: Lidocaine infusions are apparently a safe option for the management of acute pain, either post-operative or not, in the pediatric population

Regulation of human Polλ by ATM-mediated phosphorylation during Non-Homologous End Joining

DNA double strand breaks (DSBs) trigger a variety of cellular signaling processes, collectively termed the DNA-damage response (DDR), that are primarily regulated by protein kinase ataxia-telangiectasia mutated (ATM). Among DDR activated processes, the repair of DSBs by non-homologous end joining (NHEJ) is essential. The proper coordination of NHEJ factors is mainly achieved through phosphorylation by an ATM-related kinase, the DNA-dependent protein kinase catalytic subunit (DNA-PKcs), although the molecular basis for this regulation has yet to be fully elucidated. In this study we identify the major NHEJ DNA polymerase, DNA polymerase lambda (Polλ), as a target for both ATM and DNA-PKcs in human cells. We show that Polλ is efficiently phosphorylated by DNA-PKcs in vitro and predominantly by ATM after DSB induction with ionizing radiation (IR) in vivo. We identify threonine 204 (T204) as a main target for ATM/DNA-PKcs phosphorylation on human Polλ, and establish that its phosphorylation may facilitate the repair of a subset of IR-induced DSBs and the efficient Polλ-mediated gap-filling during NHEJ. Molecular evidence suggests that Polλ phosphorylation might favor Polλ interaction with the DNA-PK complex at DSBs. Altogether, our work provides the first demonstration of how Polλ is regulated by phosphorylation to connect with the NHEJ core machinery during DSB repair in human cells.España MINECO y la Comisión Europea (European Regional Development Fund) to J.F.R. RYC-2011-08752, BFU2013-44343-P) and to F.C-L. (SAF2014-55532-R)

Teaching the Medical Semiology at medical schools in the State of Rio de Janeiro

In order to describe the teaching of the Medical Semiology the State of Rio de Janeiro, we studied 14 undergraduate medical courses (11 private and 3 public). Using a quantitative and qualitative approach, data were obtained through document analysis of teaching programs, application of a form, and interviews with course coordinators. The objectives and contents of the Medical Semiology were similar between different medical schools, although they adopted different names, positions in the curriculum, and course load. The teaching-learning strategies, didactic resources, and grading or evaluation were also specific to each institution. One of the main difficulties was lack of standardization of practical teaching in basic clinical skills like medical interviews and physical examination, along with the lack of available learning scenarios and lack of integration between teaching, patient care, and research.Com o objetivo de caracterizar o ensino da Semiologia Médica no Estado do Rio de Janeiro, pesquisamos 14 cursos de graduação, sendo 11 privados e 3 públicos. Mediante abordagem quantitativa e qualitativa, os dados foram obtidos por meio de análise documental dos programas de ensino, aplicação de formulário e entrevista aos coordenadores das disciplinas. Foi observada semelhança entre os objetivos e conteúdos de Semiologia das diferentes escolas de Medicina, apesar de existir diversificação na denominação, inserção curricular e carga horária. As estratégias de ensino-aprendizagem, os recursos didáticos e a avaliação também mostraram especificidade segundo a instituição. A falta de padronização do ensino prático da Semiotécnica foi considerada uma das principais dificuldades, assim como a escassa disponibilidade de cenários de aprendizagem e de integração entre docência, assistência e pesquisa.Faculdade de Medicina de PetrópolisUniversidade Federal de São Paulo (UNIFESP)UNIFESP, EPM, São Paulo, BrazilSciEL

Ice morphology modification and solute recovery improvement by heating and annealing during block freeze-concentration of coffee extracts

Several treatments on ice blocks can be applied during block freeze-concentration to increase the solute recovery from the ice. In the present study, the changes in the ice block’s temperature and the application of annealing during the block freeze-concentration of aqueous coffee extracts were studied. The ice block was subjected to heating and annealing prior to the thawing stage. The effect of coolant temperature during ice block heating (T = -10 and -5 °C) and the application of annealing (+, -) on solute recovery and ice structure morphology was evaluated. The use of annealing during block freeze-concentration modified the ice crystal morphology and increased the solute recovery only when it is applied at the highest temperature. In general, the annealing process increased the size and circularity of the ice crystals, consequently improving the solute recovery. Thus, annealing can be used to increase the solute recovery during block freeze-concentration.Postprint (published version

Hydrodynamic profiles for an impurity in a open vibrated granular gas

The hydrodynamic state of an impurity immersed in a low density granular gas is analyzed. Explicit expressions for the temperature and density fields of the impurity in terms of the hydrodynamic fields of the gas are derived. It is shown that the ratio between the temperatures of the two components, measuring the departure from energy equipartition, only depends on the mechanical properties of the particles, being therefore constant in the bulk of the system. This ratio plays an important role in determining the density profile of the intruder and its position with respect to the gas, since it determines the sign of the pressure diffusion coefficient. The theoretical predictions are compared with molecular dynamics simulation results for the particular case of the steady state of an open vibrated granular system in absence of macroscopic fluxes, and a satisfactory agreement is found