IV paracetamol versus IV ibuprofen for the treatment of PDA in LBW infants: a randomized controlled trial

Patent ductus arteriosus is a prevalent problem in low birth weight infants and it has an important morbidity and mortality in this group of patients. Classical treatment options include drugs (intravenous cyclooxygenase inhibitors: indomethacin and ibuprofen) and surgical ligation, but these treatments are associated with significant adverse effects. An alternative treatment with fewer side effects is needed. The role of oral paracetamol has gained importance in recent years, this new therapeutic option is being widely studied, and there are already many studies which support oral paracetamol as first line treatment for PDA, due to its better safety profile than classical drugs. In LBW infants is difficult to administer enteral treatment, since they are often multi pathological patients with several complications that preclude oral administration and they usually receive intravenous treatments. This multicenter, prospective, single blinded, randomized, controlled, parallel-group and noninferiority trial is designed to evaluate the efficacy and safety of intravenous paracetamol versus intravenous ibuprofen in the treatment of PDA in LBW infants. Sixty eight infants with echocardiography confirmed PDA will be randomly assigned to receive either intravenous paracetamol or intravenous ibuprofen. The main endpoints will be the rate of ductal closure of each drug and adverse events in each group of treatment

Persistent bundles over a two dimensional compact set

"Vegeu el resum a l'inici del document del fitxer adjunt."

Reliable and persistent storage for CoDeS a distributed collaborative system

This research is aimed to find a solution for a distributed storage system adapted for CoDeS. By studying how DSSs work and how they are implemented, we can conclude how we can implement a DSS compatible with CoDeS requirements.

Mean first-passage times for systems driven by equilibrium persistent-periodic dichotomous noise

In a recent paper, [J. M. Porrà, J. Masoliver, and K. Lindenberg, Phys. Rev. E 48, 951 (1993)], we derived the equations for the mean first-passage time for systems driven by the coin-toss square wave, a particular type of dichotomous noisy signal, to reach either one of two boundaries. The coin-toss square wave, which we here call periodic-persistent dichotomous noise, is a random signal that can only change its value at specified time points, where it changes its value with probability q or retains its previous value with probability p=1-q. These time points occur periodically at time intervals t. Here we consider the stationary version of this signal, that is, equilibrium periodic-persistent noise. We show that the mean first-passage time for systems driven by this stationary noise does not show either the discontinuities or the oscillations found in the case of nonstationary noise. We also discuss the existence of discontinuities in the mean first-passage time for random one-dimensional stochastic maps.

Generalization of the persistent random walk to dimensions greater than 1

We propose a generalization of the persistent random walk for dimensions greater than 1. Based on a cubic lattice, the model is suitable for an arbitrary dimension d. We study the continuum limit and obtain the equation satisfied by the probability density function for the position of the random walker. An exact solution is obtained for the projected motion along an axis. This solution, which is written in terms of the free-space solution of the one-dimensional telegraphers equation, may open a new way to address the problem of light propagation through thin slabs.

Are R&D collaborative agreements persistent at the firm level? Empirical evidence for the Spanish case

We provide evidence on the dynamics in firms’ R&D cooperation behaviour. Our main objective is to analyse if R&D collaborative agreements are persistent at the firm level, and in such a case, to study what are the main drivers of this phenomenon. R&D cooperation activities at the firm level can be persistent due to true state dependence, this implying that cooperating in a given period enhances the probability of doing it in the subsequent period and it can also be a consequence of firms’ individual heterogeneity, so that certain firms have certain characteristics that make them more likely to carry out technological alliances.

Are R&D collaborative agreements persistent at the firm level? Empirical evidence for the Spanish case

We provide evidence on the dynamics in firms’ R&D cooperation behaviour. Our main objective is to analyse if R&D collaborative agreements are persistent at the firm level, and in such a case, to study what are the main drivers of this phenomenon. R&D cooperation activities at the firm level can be persistent due to true state dependence, this implying that cooperating in a given period enhances the probability of doing it in the subsequent period and it can also be a consequence of firms’ individual heterogeneity, so that certain firms have certain characteristics that make them more likely to carry out technological alliances.

Confirmation of persistent radio jets in the microquasar LS 5039

We present here new observations conducted with the EVN and MERLIN of the persistent microquasar LS 5039 discovered by Paredes et al. (2000) with the VLBA. The new observations confirm the presence of an asymmetric two-sided jet reaching up to 1000 AU on the longest jet arm. The results suggest a bending of the jets with increasing distance from the core and/or precession. The origin and location of the high-energy gamma-ray emission associated with the system is discussed and an estimate of the magnetic field at the base of the jet given. Our results suggest a well collimated radio jet. We also comment on new observing strategies to be used with satellites and forthcoming detectors, since this persistent source appears to be a rather good laboratory to explore the accretion/ejection processes taking place near compact objects.

Discovery of a High-Energy Gamma-Ray-Emitting Persistent Microquasar

Microquasars are stellar x-ray binaries that behave as a scaled down version of extragalactic quasars. The star LS 5039 is a new microquasar system with apparent persistent ejection of relativistic plasma at a 3 kiloparsec distance from the sun. It may also be associated with a gamma-ray source discovered by the Energetic Gamma Ray Experiment Telescope (EGRET) on board the COMPTON-Gamma Ray Observatory satellite. Before the discovery of LS 5039, merely a handful of microquasars had been identified in the Galaxy, and none of them was detected in high-energy gamma-rays.

Persistent random walk model for transport trough thin slabs

We present a model for transport in multiply scattering media based on a three-dimensional generalization of the persistent random walk. The model assumes that photons move along directions that are parallel to the axes. Although this hypothesis is not realistic, it allows us to solve exactly the problem of multiple scattering propagation in a thin slab. Among other quantities, the transmission probability and the mean transmission time can be calculated exactly. Besides being completely solvable, the model could be used as a benchmark for approximation schemes to multiple light scattering.

Characterization of nontypable haemophilus influenzae isolates recovered from adult patients with underlying chronic lung disease reveals genotypic and phenotypic traits associated with persistent infection

Nontypable Haemophilus influenzae (NTHi) has emerged as an important opportunistic pathogen causing infection in adults suffering obstructive lung diseases. Existing evidence associates chronic infection by NTHi to the progression of the chronic respiratory disease, but specific features of NTHi associated with persistence have not been comprehensively addressed. To provide clues about adaptive strategies adopted by NTHi during persistent infection, we compared sequential persistent isolates with newly acquired isolates in sputa from six patients with chronic obstructive lung disease. Pulse field gel electrophoresis (PFGE) identified three patients with consecutive persistent strains and three with new strains. Phenotypic characterisation included infection of respiratory epithelial cells, bacterial self-aggregation, biofilm formation and resistance to antimicrobial peptides (AMP). Persistent isolates differed from new strains in showing low epithelial adhesion and inability to form biofilms when grown under continuous-flow culture conditions in microfermenters. Self-aggregation clustered the strains by patient, not by persistence. Increasing resistance to AMPs was observed for each series of persistent isolates; this was not associated with lipooligosaccharide decoration with phosphorylcholine or with lipid A acylation. Variation was further analyzed for the series of three persistent isolates recovered from patient 1. These isolates displayed comparable growth rate, natural transformation frequency and murine pulmonary infection. Genome sequencing of these three isolates revealed sequential acquisition of single-nucleotide variants in the AMP permease sapC, the heme acquisition systems hgpB, hgpC, hup and hxuC, the 3-deoxy-D-manno-octulosonic acid kinase kdkA, the long-chain fatty acid transporter ompP1, and the phosphoribosylamine glycine ligase purD. Collectively, we frame a range of pathogenic traits and a repertoire of genetic variants in the context of persistent infection by NTHi.

Chaotic dynamics in credit constrained emerging economies

This paper analyzes the role of financial development as a source of endogenous instability in small open economies. By assuming that firms face credit constraints, our model displays a complex dynamic behavior for intermediate values of the parameter representing the level of financial development of the economy. The basic implication of our model is that economies experiencing a process of financial development are more unstable than both very underdeveloped and very developed economies. Our instability concept means that small shocks have a persistent effect on the long run behavior of the model and also that economies can exhibit cycles with a very high period or even chaotic dynamic patterns.