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The experimental achievements and the results obtained so far with the LPCTrap device installed at GANIL are presented. The apparatus is dedicated to the study of the weak interaction at low energy by means of precise measurements of the β − ν angular correlation parameter in nuclear β decays. So far, the data collected with three isotopes have enabled to determine, for the first time, the charge state distributions of the recoiling ions, induced by shakeoff process. The analysis is presently refined to deduce the correlation parameters, with the potential of improving both the constraint deduced at low energy on exotic tensor currents (He) and the precision on the V element of the quark-mixing matrix (Ar and Ne) deduced from the mirror transitions dataset. [ABSTRACT FROM AUTHOR]

The LPCTrap setup is a sensitive tool to measure the β − ν angular correlation coefficient, a, which can yield the mixing ratio ρ of a β decay transition. The latter enables the extraction of the Cabibbo-Kobayashi-Maskawa (CKM) matrix element V. In such a measurement, the most relevant observable is the energy distribution of the recoiling daughter nuclei following the nuclear β decay, which is obtained using a time-of-flight technique. In order to maximize the precision, one can reduce the systematic errors through a thorough simulation of the whole set-up, especially with a correct model of the trapped ion cloud. This paper presents such a simulation package and focuses on the ion cloud features; particular attention is therefore paid to realistic descriptions of trapping field dynamics, buffer gas cooling and the N-body space charge effects. [ABSTRACT FROM AUTHOR]

Objective:To characterize infants affected with perinatal hypoxic ischemic encephalopathy (HIE) who were referred to regional neonatal intensive care units (NICUs) and their related short-term outcomes.Study Design:This is a descriptive study evaluating the data collected prospectively in the Children's Hospital Neonatal Database, comprised of 27 regional NICUs within their associated children's hospitals. A consecutive sample of 945 referred infants born ⩾36 weeks' gestation with perinatal HIE in the first 3 days of life over approximately 3 years (2010-July 2013) were included. Maternal and infant characteristics are described. Short-term outcomes were evaluated including medical comorbidities, mortality and status of survivors at discharge.Result:High relative frequencies of maternal predisposing conditions, cesarean and operative vaginal deliveries were observed. Low Apgar scores, profound metabolic acidosis, extensive resuscitation in the delivery room, clinical and electroencephalographic (EEG) seizures, abnormal EEG background and brain imaging directly correlated with the severity of HIE. Therapeutic hypothermia was provided to 85% of infants, 15% of whom were classified as having mild HIE. Electrographic seizures were observed in 26% of the infants. Rates of complications and morbidities were similar to those reported in prior clinical trials and overall mortality was 15%.Conclusion:Within this large contemporary cohort of newborns with perinatal HIE, the application of therapeutic hypothermia and associated neurodiagnostic studies appear to have expanded relative to reported clinical trials. Although seizure incidence and mortality were lower compared with those reported in the trials, it is unclear whether this represented improved outcomes or therapeutic drift with the treatment of milder disease. [ABSTRACT FROM AUTHOR]

Objective:To characterize the population and short-term outcomes in preterm infants with surgical necrotizing enterocolitis (NEC).Study Design:Preterm infants with surgical NEC were identified from 27 hospitals over 3 years using the Children's Hospitals Neonatal Database; infants with gastroschisis, volvulus, major congenital heart disease or surgical NEC that resolved prior to referral were excluded. Patient characteristics and pre-discharge morbidities were stratified by gestational age (<28 vs 280/7 to 366/7 weeks' gestation).Result:Of the 753 eligible infants, 60% were born at <28 weeks' gestation. The median age at referral was 14 days; only 2 infants were inborn. Male gender (61%) was overrepresented, whereas antenatal steroid exposure was low (46%). Although only 11% had NEC totalis, hospital mortality (<28 weeks' gestation: 41%; 280/7 to 366/7 weeks' gestation: 32%, P=0.02), short bowel syndrome (SBS)/intestinal failure (IF) (20% vs 26%, P=0.06) and the composite of mortality or SBS/IF (50% vs 49%, P=0.7) were prevalent. Also, white matter injury (11.7% vs 6.6%, P=0.02) and grade 3 to 4 intraventricular hemorrhages (23% vs 2.7%, P<0.01) were commonly diagnosed. After referral, the median length of hospitalization was longer for survivors (106 days; interquartile range (IQR) 79, 152) relative to non-survivors (2 days; IQR 1,17; P<0.001). These survivors were prescribed parenteral nutrition infrequently after hospital discharge (<28 weeks': 5.2%; 280/7 to 366/7 weeks': 9.9%, P=0.048).Conclusion:After referral for surgical NEC, the short-term outcomes are grave, particularly for infants born <28 weeks' gestation. Although analyses to predict outcomes are urgently needed, these data suggest that affected infants are at a high risk for lengthy hospitalizations and adverse medical and neuro-developmental abnormalities. [ABSTRACT FROM AUTHOR]

The Children's Hospitals Neonatal Consortium is a multicenter collaboration of leaders from 27 regional neonatal intensive care units (NICUs) who partnered with the Children's Hospital Association to develop the Children's Hospitals Neonatal Database (CHND), launched in 2010. The purpose of this report is to provide a first summary of the population of infants cared for in these NICUs, including representative diagnoses and short-term outcomes, as well as to characterize the participating NICUs and institutions. During the first 2 1/2 years of data collection, 40910 infants were eligible. Few were born inside these hospitals (2.8%) and the median gestational age at birth was 36 weeks. Surgical intervention (32%) was common; however, mortality (5.6%) was infrequent. Initial queries into diagnosis-specific inter-center variation in care practices and short-term outcomes, including length of stay, showed striking differences. The CHND provides a contemporary, national benchmark of short-term outcomes for infants with uncommon neonatal illnesses. These data will be valuable in counseling families and for conducting observational studies, clinical trials and collaborative quality improvement initiatives. [ABSTRACT FROM AUTHOR]

Objective:To estimate the risk of death or tracheostomy placement (D/T) in infants with severe bronchopulmonary dysplasia (sBPD) born <32 weeks' gestation referred to regional neonatal intensive care units.Study Design:We conducted a retrospective cohort study in infants born <32 weeks' gestation with sBPD in 2010-2011, using the Children's Hospital Neonatal Database. sBPD was defined as the need for FiO2 ⩾0.3, nasal cannula support >2 l min−1 or positive pressure at 36 weeks' post menstrual age. The primary outcome was D/T before discharge. Predictors associated with D/T in bivariable analyses (P<0.2) were used to develop a multivariable logistic regression equation using 80% of the cohort. This equation was validated in the remaining 20% of infants.Result:Of 793 eligible patients, the mean gestational age was 26 weeks' and the median age at referral was 6.4 weeks. D/T occurred in 20% of infants. Multivariable analysis showed that later gestational age at birth, later age at referral along with pulmonary management as the primary reason for referal, mechanical ventilation at the time of referral, clinically diagnosed pulmonary hypertension, systemic corticosteroids after referral and occurrence of a bloodstream infection after referral were each associated with D/T. The model performed well with validation (area under curve 0.86, goodness-of-fit χ2, P=0.66).Conclusion:Seven clinical variables predicted D/T in this large, contemporary cohort with sBPD. These results can be used to inform clinicians who counsel families of affected infants and to assist in the design of future prospective trials. [ABSTRACT FROM AUTHOR]

Objective:To characterize the treatments and short-term outcomes in infants with severe bronchopulmonary dysplasia (sBPD) referred to regional neonatal intensive care units.Study Design:Infants born <32 weeks' gestation with sBPD were identified using the Children's Hospital Neonatal Database. Descriptive outcomes are reported.Result:A total of 867 patients were eligible. On average, infants were born at 26 weeks' gestation and referred 43 days after birth. Infants frequently experienced lung injury (pneumonia: 24.1%; air leak: 9%) and received systemic corticosteroids (61%) and mechanical ventilation (median duration 37 days). Although 91% survived to discharge, the mean post-menstrual age was 47 weeks. Ongoing care such as supplemental oxygen (66%) and tracheostomy (5%) were frequently needed.Conclusion:Referred infants with sBPD sustain multiple insults to lung function and development. Because affected infants have no proven, safe or efficacious therapy and endure an exceptional burden of care even after referral, urgent work is required to observe and improve their outcomes. [ABSTRACT FROM AUTHOR]

BACKGROUND/OBJECTIVES:Compromised vitamin D status is common in pregnancy and may have adverse impacts on fetal development. The purpose of this study was to investigate the association of infant whole-body bone mineral content (WBBMC) at 8-21 days of age with feto-maternal vitamin D status in a multiethnic population in Oakland, California.SUBJECTS/METHODS:This was a cross-sectional study of 120 women and their newborn infants. Maternal and cord blood were collected at delivery. WBBMC was measured by dual-energy X-ray absorptiometry in term-born infants 8-21days post birth.RESULTS:No significant association was observed between unadjusted or size-adjusted WBBMC and feto-maternal vitamin D status analyzed continuously or categorically. In multivariate modeling, unadjusted WBBMC was predicted by bone area (P<0.0001), weight-for-age (P<0.0001) and weight-for-length (P=0.0005) Z-scores, but not by feto-maternal vitamin D status. Anthropometric predictors but not vitamin D remained significant in the multivariate model after adjustment of WBBMC for weight, bone area (bone mineral density) or logarithmically derived exponents of the denominators.CONCLUSIONS:Results of the present study do not support an association between feto-maternal vitamin D status and early infant WBBMC, raw or adjusted for inter-individual differences in size, in a multiethnic population in Northern California. [ABSTRACT FROM AUTHOR]

This article provides an overview of the current literature on the relationships between media consumption and sleep in children and adolescents. To date, the majority of studies are cross-sectional studies reporting a significant negative correlation between media consumption and the quality of sleep. Interventional studies further investigating the cause-effect chain are rare. Potential reasons and consequences of sleep disruptions are reviewed and discussed. Given the high prevalence of media consumption in children and adolescents, future studies are needed to increase awareness in parents and society at large and to provide advice and guidance on acceptable amounts of media consumption. [ABSTRACT FROM AUTHOR]

Objective:Many premature infants at risk for bronchopulmonary dysplasia experience episodes of surfactant dysfunction with reduced surfactant protein B (SP-B). In this study, we investigated the safety and responses to booster doses of surfactant.Study Design:A total of 87 infants, 500 to 1250 g birth weight, who were ventilated at 7 to 10 days received 2 or 3 doses of Infasurf (Calfactant, Forest Pharmaceuticals, St Louis, MO, USA) within a 1-week period.Result:For 184 doses, occurrence rates of transient bradycardia (13) and plugged endotracheal tube (5) were low, and no other adverse effects were noted. Treatment transiently improved the respiratory severity score (FiO2 × mean airway pressure), SP-B content (+75%) and surface properties of isolated surfactant. Levels of eight proinflammatory cytokines in tracheal aspirate were interrelated and unchanged from baseline after surfactant treatment.Conclusion:Booster doses of surfactant for premature infants with lung disease are safe and transiently improve respiratory status as well as composition and function of endogenous surfactant. [ABSTRACT FROM AUTHOR]

The purpose of this randomized study was to measure the influence of 6 weeks of LCPUFA (600 mg EPA and 400 mg DHA per day) supplementation alone or in association with 30 mg vitamin E, 60 mg vitamin C and 6 mg β-carotene on resting and exercise-induced lipid peroxidation in judoists (n = 36). Blood samples were collected at rest before (T (1)) and after the supplementation period, in preexercise (T (2)) and postexercise (T (3)) conditions, for analysis of α-tocopherol, retinol, lag phase (Lp) before free radical-induced oxidation, maximum rate of oxidation (R (max)) during the propagating chain reaction, maximum amount of conjugated dienes (CD(max)) accumulated after the propagation phase, and nitric oxide, malondialdehyde and lipoperoxide (POOL) concentrations. Dietary data were collected using a 7-day diet record. There were no significant differences among treatment groups with respect to habitual intakes of energy from fat, carbohydrate, or protein. At T (1), there were no significant differences among treatment groups with respect to lipid peroxidation, lag phase, and levels of α-tocopherol or retinol. The consumption of an n-3 LC PUFA supplement increased oxidative stress at rest and did not attenuate the exercise-induced oxidative stress. The addition of antioxidants did not prevent the formation of oxidation products at rest. On the contrary, it seems that the combination of antioxidants added to the n-3 LCPUFA supplement led to a decrease in, CD(max), R (max), and POOL and MDA concentrations after a judo training session. [ABSTRACT FROM AUTHOR]

The LPCTrap setup is a transparent Paul trap dedicated to the measurement of the β- ν correlation coefficient a in the β decay of trapped radioactive nuclides. In a first experiment, the system has been used to record ∼10 coincidences between the β particles and recoiling ions emitted from the decay of He ions. The analysis of the collected data has already shown that the size of the He ion cloud confined in the Paul trap is a critical parameter, potentially limiting the accuracy on the a measurement. We report here the precise determination of the trapped ion cloud temperature and size. This was performed by extracting the trapped ions toward a position sensitive micro channel plate detector at different phases of the RF driving field. We find a temperature T = 0.107(7) eV, consistent with the temperature values inferred using two other observables but 20% higher than the temperature T = 0.09 eV predicted by realistic simulations of the ions interacting with the H buffer gas. [ABSTRACT FROM AUTHOR]

The LPCTrap experiment is devoted to the precise measurement of the β- ν angular correlation parameter, a, in the pure Gamow-Teller decay of He. This experiment is motivated by the search of the presence of tensor type contributions in the weak interaction. The radioactive source is confined in a transparent Paul trap installed at LIRAT, the low energy beam line of the SPIRAL facility. The β- ν correlation is studied by measuring the time of flight of the recoil ions detected in coincidence with the β particles. During the last experiment, a total of 4 × 10 coincidence events have been recorded which would enable to determine the coefficient with a statistical uncertainty of 0.5%. The status of the analysis is presented in this contribution. [ABSTRACT FROM AUTHOR]

Hardening of steel after induction surface heating is studied. Amodel of the process of hardening of a cylinder is created and subjected to numerical simulation in order to determine the stresses formed in the part. Two principal methods for describing the variation of the stress state during the treatment are developed. Residual stresses are analyzed in both models and compared with the results of an x-ray study. The correlation between the measured data and the numerical results is discussed. [ABSTRACT FROM AUTHOR]

The LPCTrap setup at GANIL is fully operational since 2006. The first breakthrough was the detection of 100000 coincidences between the $ \beta$ particles and the recoil ions from the decay of 6He+ produced by the SPIRAL source. After preparation, the decaying nuclei are confined in a transparent Paul trap which is surrounded by a $ \beta$ -telescope made of a double-sided silicon strip detector followed by a scintillator, and by a micro-channel plate position-sensitive detector to record in coincidence the $ \beta$ particles and the recoil ions. Simulations of this system are needed in order to study possible systematic effects and extract with high accuracy the $ \beta$ - $ \nu$ angular-correlation coefficient. A code based on Geant4 is well suited for this purpose. In this contribution the results from the simulations compared with those from the experiment will be presented and discussed. [ABSTRACT FROM AUTHOR]

The measurement of the two-particle correlation function for different particle species allows to obtain information about the development of the particle emission process: the space-time properties of emitting sources and the emission time sequence of different particles. The single-particle characteristics and two-particle correlation functions for neutral and charged particles registered in forward direction are used to determine that the heavy fragments (deuterons and tritons) are emitted in the first stage of the reaction (pre-equilibrium source) while the majority of neutrons and protons originates from the long-lived quasi-projectile. The emission time sequence of protons, neutrons and deuterons has been obtained from the analysis of non-identical particle correlation functions. [ABSTRACT FROM AUTHOR]

The LPCTrap facility is coupled to the low-energy beam line LIRAT of the SPIRAL source at GANIL (France). The facility comprises an RFQ trap for beam preparation and a transparent Paul trap for in-trap decay studies. The system has been tested for several ion species. The Paul trap has been fully characterized for 6Li+ and 23Na+ ions. This characterization together with GEANT4 simulations of the in-trap decay setup (Paul trap and detection system) has permitted to predict the effect of the size of the ion cloud on the decay study of 6He+. [ABSTRACT FROM AUTHOR]

The results from ten statistical multifragmentation models have been compared with each other using selected experimental observables. Even though details in any single observable may differ, the general trends among models are similar. Thus, these models and similar ones are very good in providing important physics insights especially for general properties of the primary fragments and the multifragmentation process. Mean values and ratios of observables are also less sensitive to individual differences in the models. In addition to multifragmentation models, we have compared results from five commonly used evaporation codes. The fluctuations in isotope yield ratios are found to be a good indicator to evaluate the sequential decay implementation in the code. The systems and the observables studied here can be used as benchmarks for the development of statistical multifragmentation models and evaporation codes. [ABSTRACT FROM AUTHOR]

We report on the status of the LPCTrap experiment, devoted to measure the β–ν angular correlation in the pure Gamow–Teller decay of 6He. This measurement is motivated by the search for the presence of tensor type contributions to the weak interaction. The 6He ions are confined in a novel transparent Paul trap. The β particles and the recoil ions are detected in coincidence to deduce the angular correlation parameter. The commissioning run performed in 2005 has given the proof of principle of this experiment. Up to 105 coincidences were recorded during a second run in 2006. [ABSTRACT FROM AUTHOR]

Off-lattice dynamic Monte-Carlo simulations were done of reversible cluster-cluster aggregation for spheres that form rigid bonds at contact. The equilibrium properties were found to be determined by the life time of encounters between two particles (te). te is a function not only of the probability to form or break a bond, but also of the elementary step size of the Brownian motion of the particles. In the flocculation regime the fractal dimension of the clusters is df=2.0 and the size distribution has a power law decay with exponent τ=1.5. At larger values of te transient gels are formed. Close to the percolation threshold the clusters have a fractal dimension df=2.7 and the power law exponent of the size distribution is τ=2.1. The transition between flocculation and percolation occurs at a characteristic weight average aggregation number that decreases with increasing volume fraction. [ABSTRACT FROM AUTHOR]

Directed and elliptic flow for the 197Au+197Au system at incident energies between 40 and 150 MeV per nucleon has been measured using the INDRA 4π multi-detector. For semi-central collisions, the excitation function of elliptic flow shows a transition from in-plane to out-of-plane emission at around 100 MeV per nucleon. The directed flow changes sign at a bombarding energy between 50 and 60 MeV per nucleon and remains negative at lower energies. Molecular dynamics calculations (CHIMERA) indicate sensitivity of the global squeeze-out transition on the σ NN and demonstrate the importance of angular momentum conservation in transport codes at low energies. [ABSTRACT FROM AUTHOR]

The influence of the Brownian step size in off-lattice Monte Carlo simulations of the aggregation and gelation of spheres is studied. It is found that the kinetics are strongly influenced if the step size is larger than the mean smallest distance between the sphere surfaces. The structure of the clusters and the gels is influenced, but only over length scales smaller than the step size. Using large step sizes leads to a narrower size distribution of the clusters. Implications of the present results are discussed for simulations reported in the literature in which the Brownian step size was chosen equal to the sphere diameter. [ABSTRACT FROM AUTHOR]

Quantum tunnelling through a potential barrier (such as occurs in nuclear fusion) is very sensitive to the detailed structure of the system and its intrinsic degrees of freedom. A strong increase of the fusion probability has been observed for heavy deformed nuclei. In light exotic nuclei such as6He,11Li and11Be (termed‘halo’nuclei), the neutron matter extends much further than the usual nuclear interaction scale. However, understanding the effect of the neutron halo on fusion has been controversial-it could induce a large enhancement of fusion, but alternatively the weak binding energy of the nuclei could inhibit the process. Other reaction channels known as direct processes (usually negligible for ordinary nuclei) are also important: for example, a fragment of the halo nucleus could transfer to the target nucleus through a diminished potential barrier. Here we study the reactions of the halo nucleus6He with a238U target, at energies near the fusion barrier. Most of these reactions lead to fission of the system, which we use as an experimental signature to identify the contribution of the fusion and transfer channels to the total cross-section. At energies below the fusion barrier, we find no evidence for a substantial enhancement of fusion. Rather, the (large) fission yield is due to a two-neutron transfer reaction, with other direct processes possibly also involved. [ABSTRACT FROM AUTHOR]

Lattice and off-lattice Monte Carlo simulations of diffusion-limited cluster aggregation and gelation were done over a broad range of concentrations. The large-scale structure and the size distribution of the clusters are characterized by a crossover at a characteristic size (). For, they are the same as obtained in a dilute DLCA process and forthey are the same as obtained in a static percolation process.is determined by the overlap of the clusters and decreases with increasing particle concentration. The growth rate of large clusters is a universal function of time reduced by the gel time. The large-scale structural and temporal properties are the same for lattice and off-lattice simulations. The average degree of connectivity per particle in the gels formed in off-lattice simulations is independent of the concentration, but its distribution depends on the concentration. [ABSTRACT FROM AUTHOR]

Diffusion-limited cluster aggregation and gelation are studied using lattice and off-lattice Monte Carlo simulations. The pair correlation functiong(r) and the structure factorS(q) of the particle gels were investigated as a function of the volume fraction () and time. At volume fractions below, the gel structure is fractal on small length scales with.g(r) shows a weak minimum at the correlation length (), before reaching the average concentration at large length scales. The cut-off function ofg(r) varies during the aggregation process, but at a given, whereis the gel time, it is a universal function of. At high volume fractions, the structure is dominated by excluded-volume interactions, while at low volume fractions, it is determined by the connectivity. [ABSTRACT FROM AUTHOR]

Low-energy π+ (Eπ &lsim; 35 MeV) from 12C + 197Au collisions at incident energies from 300 to 1800 MeV per nucleon were detected with the Si-Si(Li)-Csl(TI) calibration telescopes of the INDRA multidetector. The inclusive angular distributions are approximately isotropic, consistent with multiple rescattering in the target spectator. The multiplicity correlations of the low-energy pions and of energetic protons (Ep &gsim; 150 MeV) with intermediate-mass fragments were determined from the measured coincidence data. The deduced correlation functions 1 + R &ap; 1.3 for inclusive event samples reflect the strong correlations evident from the common impact parameter dependence of the considered multiplicities. For narrow impact parameter bins (based on charged-particle multiplicity), the correlation functions are close to unity and do not indicate strong additional correlations. Only for pions at high particle multiplicities (central collisions) a weak anticorrelation is observed, probably due to a limited competition between these emissions. Overall, the results are consistent with the equilibrium assumption made in statistical multifragmentation scenarios. Predictions obtained with intranuclear-cascade models coupled to the Statistical Multifragmentation Model are in good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

Results of the experimental study of p4He, d3He, dT, pT, p3He and, for the first time, nT, n3He, n4He correlations in the region of small relative momenta are presented. The data analysis provides an estimate of the effective source size or emission time. [ABSTRACT FROM AUTHOR]

The transport properties of the 36Ar + 58Ni system at 95 A. MeV measured with the INDRA array, are studied within the BNV kinetic equation. A general protocol of comparison between the N-body experimental fragment information and the one-body distribution function is developed using global variables, with a special focus on charge density. This procedure avoids any definition of sources and any use of an afterburner in the simulation. We shall discuss the feasibility of such an approach and the distortions induced by the finite detection efficiency and the completeness requirements of the data selection. The sensitivity of the different global observables to the macroscopic parameters of the effective nuclear interaction will be studied in detail. [ABSTRACT FROM AUTHOR]

: We present off-lattice Monte Carlo simulations of site-bond percolation of semi-penetrable spheres or, equivalently, of hard spheres with a finite bond range. We will show that the crucial parameter is the effective volume fraction ( φe), i.e. the volume that is occupied or within the bond range of at least one particle. For the equivalent system of semi-penetrable spheres 1 - φe is the porosity. The bond percolation threshold (pb) can be described in terms of φe by a simple analytical expression: log(φe)/log(φec) + log(pb)/log(pbc) = 1, with pbc = 0.12 independent of the bond range and φec a constant that decreases with increasing bond range. [ABSTRACT FROM AUTHOR]

A linear radiofrequency quadrupole has been built at the LPC-Caen for the manipulation of radioactive ions. The system was designed for the cooling and bunching of a continuous beam using the buffer gas cooling technique. The technique is being extended to its ultimate limit to apply it for the cooling of light ions using H2 as buffer gas. The bunches are to be injected into a transparent Paul trap for further decay studies. The cooling and bunching section of the system has been successfully tested off-line with a source of stable ions. We describe here the specifications of the device and present the results of the first tests. [ABSTRACT FROM AUTHOR]

Monte-Carlo simulations of reversible aggregation on a cubic lattice were done by introducing a finite probability ( P) of nearest neighbours to form a bond. Depending on the volume fraction of occupied sites (φ) and P we observed different phenomena by monitoring as a function of time the space filling and the distribution of the aggregates and the gel fraction. At smaller values of P the system develops into an equilibrium distribution of aggregates of which the average size increases with increasing φ until above a critical value the system percolates. At larger values of P the system phase separates into two phases with different densities. Above a critical value of φ the system percolates during a finite time. The life time of the gel and the maximum gel fraction were studied as a function of P. [ABSTRACT FROM AUTHOR]

Objective: The comparative bioavailability of two oral formulations of cefixime, the Oroken[sup ®] 200mg tablet (reference formulation) and the novel Oroken[sup ®] 200mg sachet (test formulation), was investigated in a single-dose crossover study in 18 healthy male volunteers.Results: The data obtained in this study demonstrated bioequivalence of the two formulations. No statistical differences were observed for either maximum serum drug concentrations (C[sub max]) or areas under serum drug concentration versus time curves (AUC). 90% confidence intervals for mean C[sub max] and mean AUC (logarithmically transformed data) of the sachet as compared with the tablet were within the bioequivalence interval of 0.8 to 1.25. No differences between formulations in time to reach C[sub max] (t[sub max]) or serum elimination half-life (t[sub ½β]) were evident. Moreover, after administration of either formulation, comparable amounts of unchanged cefixime were excreted in urine over similar time-frames. Clinical and biological tolerability was excellent for both formulations.Conclusion: The results of the present study show bioequivalence in terms of rate and extent of absorption of the tablet and sachet formulations of cefixime. The novel sachet formulation appears of considerable use for patients who are unable or unwilling to take tablets and for whom therapy with cefixime is recommended. [ABSTRACT FROM AUTHOR]

The prompt component at intermediate velocity of light charged particles is investigated. An improved coalescence model coupled to the intra-nuclear cascade code ISABEL is used to obtain light complex particle energy spectra and multiplicities as a function of impact parameter. The results are compared with experimental data from the 36Ar + 58Ni experiment at 95 MeV/nucleon, performed with the INDRA 4π detection system. The calculated prompt component is found to rather well reproduce proton spectra. For complex light charged particles the calculated components well populate the high energy part of spectra. Prompt emission can therefore explain the large transverse energies experimentally observed at mid-rapidity. [ABSTRACT FROM AUTHOR]

Two-neutron correlation functions are measured in the 40Ar + 197Au reaction at 60 MeV/nucleon to study the space-time characteristics of neutron emitting sources. The source temperatures and velocities are deduced by fitting the single-neutron energy spectra with a three-source model. A comparison of the correlation data with the predictions of the model of moving sources and with the dynamical Landau-Vlasov model suggests the relevance of a multisource description. Particular care has been paid to the influence of the relative source abundance on the shape of the correlation function. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) Monte Carlo simulations of diffusion limited cluster aggregation at different concentrations (φ) show a crossover from a flocculation regime at short times to a percolation regime close to the gel time (tg). Contrary to suggestions in the literature tg is independent of the system size (L) for large L. The structural and temporal crossovers between flocculation and percolation take place at characteristic values of the cluster mass (mc) and the time (tc) which depend on φ. After normalisation by these characteristic values the crossovers are independent of φ except for very small clusters and at short times. The concentration dependence of mc and tc indicates that the crossover takes place at a given cumulated volume fraction of the clusters independent of φ. At low concentrations the φ-dependence of tg is determined by the cluster growth in the flocculation regime. [ABSTRACT FROM AUTHOR]

Cross sections for stripping and dissociation of deuterons interacting with Be targets in the 100–2300 MeV energy range have been measured. Comparisons with model calculations suggest a dominant contribution of the stripping process. It is also shown that the deuteron break-up cross section exhibits the same energy dependence as the nucleon-nucleon cross section. [ABSTRACT FROM AUTHOR]

Objective: Laboratory data are key evaluation procedures for Phase I clinical pharmacology for two reasons. Firstly, laboratory data are used within the screening process to exclude subjects with asymptomatic diseases, which could result in increased danger to themselves or confuse interpretation of the study results. Secondly, during study implementation, safety evaluation and in particular maximum tolerated dose determination have to be done by a case-by-case analysis, sometimes using laboratory adverse events (LAEs). Thus, relevant limits are needed to discriminate between a usual common variation and a significant abnormality, which is considered to be a LAE. This report presents laboratory data distribution, reference values and reference changes and, based on previously published new methods, suggests inclusion limits at screening and laboratory adverse event limits for analysis during study implementation. Subjects and methods: Nine hundred and twenty-seven young healthy male volunteers were recruited in one centre (Association de Recherche Thérapeutique). A standard screening process was carried out. Protocols were approved by the local ethics committee. Blood sampling was performed in the same conditions. Reference values (at screening and at baseline) were determined by a non-parametric procedure selecting 2.5% and 97.5% of the distribution of data. Reference changes were also defined as the 2.5–97.5% interval of distribution of the variations between the end of treatment and baseline. Inclusion limit and LAE limit methods of determination used had been specified in previous articles. Results: Detailed results of laboratory data distribution, reference values at screening and at baseline, reference changes, inclusion limits and LAE limits are presented in tables with number of subjects, mean, median, standard deviation, minimal and maximal values and the 2.5–97.5% interval for each laboratory parameter. Conclusion: The key aims of this paper are to provide clinical pharmacologists with data, reference values or changes obtained in the real conditions of Phase I study implementation, and to propose relevant limits, either for screening as inclusion limits, or during studies as LAE limits. Thus, these data, reference values and specific limits improve the capacity to screen healthy volunteers and to analyse LAEs during Phase I studies. [ABSTRACT FROM AUTHOR]

3d lattice Monte-Carlo simulations were done to obtain the mass distribution ( N( m)) and pair correlation function ( g( r)) of percolating clusters. We give analytical expressions of the external cut-off functions of N( m) at the z-average mass and of g( r) at the radius of gyration. The simulation results were compared with experimental results on gel forming systems reported in the literature. The comparison shows that the experimental results are compatible with the simulation results. However, more experiments are needed before we can be confident that the percolation model is a good model for the sol-gel transition. [ABSTRACT FROM AUTHOR]

Free radical co-polymerization of methyl methacrylate (MMA) and ethyl glycol dimethyl metacrylate (EGDMA) was investigated in solution at different molar ratios R = [EGDMA]/[MMA] between 0 and 0.05. Initially mainly linear PMMA was formed with weight average molar mass 7.5 g/mol independent of R. At larger reaction extents branched polymers were formed and the systems gelled. The scattering intensity rose initially with the reaction extent, but reached a plateau value at larger reaction extents. The plateau value increased strongly with R. Dynamic light scattering showed the appearance of a slow relaxation not observed in linear PMMA solutions. The data can be interpreted by assuming that the excess scattering originates from the branching points and relaxes through self diffusion of the branched particles. The results agree with predictions of the percolation model for gelation and Rouse dynamics. Viscosity measurements corroborate this interpretation. Measurements on a progressively diluted sample quenched close to the gel point again showed quantitative agreement with the percolation model for gelation. [ABSTRACT FROM AUTHOR]

Free radical co-polymerization of methyl methacrylate (MMA) and ethyl glycol dimethyl methacrylate (EGDMA) in solution leads to the formation of polydisperse branched PMMA which grows in size until the system gels. The structure and the size distribution of the PMMA aggregates were characterized at infinite dilution using static and dynamic light scattering and size exclusion chromatography (SEC). The reaction extent was measured using SEC and Raman spectroscopy. The results show that the structure and size distribution of PMMA aggregates formed close to the gel point are compatible with those of percolating clusters. The structure factor of semi-dilute solutions of PMMA aggregates is the same as that of dilute solutions at distance scales much smaller than the correlation length of the concentration fluctuations ( ). However, the cut-off function of the pair correlation function at for semi-dilute solutions is more gradual than the cut-off function at for dilute solutions. [ABSTRACT FROM AUTHOR]