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The waiting time distribution of emissions in Coronal Mass Ejections (CMEs) with several emissions is examined. We define the waiting time as the time interval between the commencement of an emission and the commencement of the next emission considered as parts of a unique CME. The distribution seems to follow a power-law. Two classes of CMEs several emissions are considered: “close” and “separate” depending on angular distance between emissions.

We present classical trajectory Monte Carlo (CTMC) calculations of total and partial cross sections for capture and ionization in Ar18+, Ar17+, Ar16++H(1s) collisions in the 30–300 keV amu−1 impact energy range. We specially focus on capture into high-lying states of the projectile, which are of paramount importance for diagnostics of fusion plasmas involving Arq+ seeding.

Ethylene/styrene copolymers were synthesized under constant polymerization conditions using six different metallocene catalysts activated with methylaluminoxane. For all the catalysts used, the activity and molecular weight of the copolymers produced decreased with the amount of styrene in the reactor feed, but the styrene content of the copolymers increased. Catalysts with carbon bridges and bulky ligands gave rise to copolymers with higher styrene content. As a result of the increased styrene content of the copolymer, the melting temperature decreased. This effect was ascribed to a decrease in the crystallinity of the copolymers. It was also found that lamellar thickness could be significantly diminished by the incorporation of comonomers. The copolymers showed a broad spectrum of mechanical properties as a function of the comonomer ratio. At low styrene contents, they behaved like typical semicrystalline thermoplastics, and at higher styrene contents, they exhibited the properties typical of elastomers. Of the catalysts tested, [rac-ethylenebis(4,5,6,7-tetrahydro-1-indenyl)]zirconium dichloride emerged as the most promising for the production of ethylene/styrene copolymers. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3420–3429, 2006

We present calculations of electron capture cross sections in collisions of O2+ and N2+ with H(1s) for impact energies 0.001 eV < E < 10 keV and the corresponding rate coefficients for temperatures 102 K < T < 105 K. Our molecular close-coupling treatment leads to significant differences from the capture rates usually employed in the modeling of astrophysical plasmas.

This document is the unedited author's version of a Submitted Work that was subsequently accepted for publication in The Journal of of Physical Chemistry Letters, copyright © American Chemical Society after peer review. To access the final edited and published work, see DOI: http://dx.doi.org/10.1021/jz5022894, A quantum-mechanical study of the predissociation of H2O+(B˜ 2B2) is carried out by using wave packet propagations on ab initio potential energy surfaces connected by nonadiabatic couplings. The simulations show that within the first 30 fs, 80% of the initial wave packet is transferred from the B 2B2 to the A˜ 2A1 electronic state through a conical intersection. A much slower transfer (in the ps timescale) from the A˜ 2A1 to the X˜2B1 state due to a Renner-Teller coupling determines the fragmentation branching ratios, which are in accordance with the experimental measurements, This work has been partially supported by projects ENE2007-62934 and ENE2011-28200 (Secretaría de Estado de I+D+i, Spain) and the European COST actions CM1204 (XLIC) and MP1002 (Nano-IBCT). The calculations have been performed at the Centro de Computación Científica of the UAM.

Prospective, open-label, comparative study, to assess the effects of sildenafil on blood pressure in a population of patients with spinal cord injury (SCI).To determine the effect of sildenafil on blood pressure in patients with erectile dysfunction secondary to SCI by comparing changes in blood pressure in SCI patients with a neurologic level below T5 versus higher levels. To establish a relationship between the potential hypotensive effect and protective muscle spasm against blood pressure reduction. To assess the effects of age, complexity and duration of SCI on changes in blood pressure. To record any adverse effects occurring during the study.Spinal Cord Injury Unit, Insular University Hospital of Gran Canaria, Canary Islands, Spain.In total, 22 male SCI patients aged 18 years or older with a history of SCI greater than 3 months in duration.Patients with erectile dysfunction secondary to SCI were included in the study, without excluding patients with a neurologic level above 75 or asymptomatic low blood pressure. Patients with specific contraindications for use of the drug were excluded. A personal history was obtained, and the level of injury (ASIA/IMSOP scales of international standards), impairment grade (ASIA impairment scale), spasticity grade (modified Ashworth scale) and baseline sitting and supine blood pressure values were determined. A single dose of 50 mg of sildenafil was administered, and patients remained sitting at 45 degrees . Blood pressure was monitored every 10 min for 4 h and whenever the patient reported symptoms. Any relevant signs and symptoms manifested during the study period were also recorded. Analysis of the changes in blood pressure values was performed using a paired t-test in each group of patients according to neurologic level and spasticity grade.A decrease in blood pressure was observed in all patients, although patients with a level of injury at T5 or above and those with a complete SCI showed a less intense decrease (P0.05). The spasticity grade of the patients was protective against the fall in blood pressure, as it was less significant in patients with grade 3 (P0.1) than in those with grade 0. Adverse effects were few and transient. None were related to hypotension.Sildenafil caused a decrease in blood pressure in SCI patients with a neurologic level of injury above T5 and complete injuries (grade A), but did not have clinical implications in the patients studied. A higher spasticity grade tends to protect the patient from the fall in blood pressure. Age and duration of injury do not appear to influence this decrease.

We present an ab initio study of H 2 + + H(1s) collisions at H 2 + impact energies between 0.4 and 50 keV. Cross sections are obtained within the sudden approximation for rotation and vibration of the diatomic molecule. We have found that anisotropy effects are crucial to correctly describe this system in this energy range.

Source length scales are estimated for the September 14, 2005 solar noise storm from the spectral and temporal observed characteristics of the background continuum fluctuations and clusters of Type I bursts. The characteristic height of the magnetic structure where the noise storm source is located and the size of the source where Type I bursts clustering takes place were calculated. A lower limit for the height of the magnetic structure supporting the noise storm at 237 MHz was estimated too.

The lowest two ab initio potential energy surfaces (PES), and the corresponding nonadiabatic couplings between them, have been obtained for the H3+ system; the molecular data are compared to those calculated with the diatomic in molecules (DIM) method. The form of the couplings is discussed in terms of the topology of the molecular structure of the triatomic. The method of Baer is employed to generate "diabatic" states and the residual nonadiabatic couplings are calculated. The ab initio results for these are markedly different from the corresponding DIM data, and show the need to consider the third PES.

We perform molecular close-coupling and impact-parameter classical trajectory Monte Carlo calculations of total and partial cross sections for capture and ionization in collisions of highly charged ions on H(1s). We first consider Li3++H(1s) as a benchmark to ascertain the complementarity of the methods, and then Ne10++H(1s), which has been scarcely studied up to now, and has recently become of interest for fusion plasma research.

We present a method to ensure the sign consistency of dynamical couplings between ab initio three-center wave functions. The method also allows to systematically "diabatize" avoided crossings between two potential energy surfaces, including conical intersections. Illustrations are presented for H(3)(+), LiH(2)(+), and NH(2)(5+) quasimolecules.

SORB (selected observed residual breakpoints) induced by ionizing radiation or endonucleases are often non-randomly distributed in mammalian chromosomes. However, the role played by chromatin structure in the localization of chromosome SORB is not well understood. Anti-topoisomerase drugs such as etoposide are potent clastogens and unlike endonucleases or ionizing radiation, induce DNA double-strand breaks (DSB) by an indirect mechanism. Topoisomerase II (Topo II) is a main component of the nuclear matrix and the chromosome scaffold. Since etoposide leads to DSB by influencing the activity of Topo II, this compound may be a useful tool to study the influence of the chromatin organization on the distribution of induced SORB in mammalian chromosomes. In the present work, we compared the distribution of SORB induced during S-phase by etoposide or X-rays in the short euchromatic and long heterochromatic arms of the CHO9 X chromosome. The S-phase stage (early, mid or late) at which CHO9 cells were exposed to etoposide or X-rays was marked by incorporation of BrdU during treatments and later determined by immunolabeling of metaphase chromosomes with an anti-BrdU FITC-coupled antibody. The majority of treated cells were in late S-phase during treatment either with etoposide or X-rays. SORB induced by etoposide mapped preferentially to Xq but random localization was observed for SORB produced by X-rays. Possible explanations for the uneven distribution of etoposide-induced breakpoints along Xq are discussed.

Close-coupling calculations of single (dissociative and nondissociative) and double electron capture cross sections in He2++H2 collisions in the range of impact energies 0.5–25 keV/amu are presented and compared with experimental data. The calculations have been carried out at the Franck–Condon level and employing both ab initio expansions, in terms of three-center electronic functions, and the independent particle model approximation. We discuss the mechanisms of the processes and the validity limits of these treatments.

We present close-coupling calculations of total cross sections for single and double electron capture in He2+ + H 2 collisions in the range 0.5– 25 keV amu−1, and compare them with experimental data. We confirm the experimental finding that the dominant process for E 3 keV amu−1 is the nondissociative capture He2+ + H 2 → He+(2l) + H 2+ (1σ g), while at lower energies it is dissociative capture leading to He+(1s) + H+ + H. Our calculations also show that He(1s2l) is the main output of the two electron capture process.

We show how to extract information from the usual programs of molecular structure, regarding the wavefunctions representing electronic vibration (and rotation) in molecules, due to the following by the electrons of the nuclei in their motion.

The charge transfer process is studied in proton collisions with BeH. Given the anisotropy of the target molecule, two approaches are considered, and compared, in order to calculate orientation-averaged cross sections. The necessary molecular data (electronic energies and non-adiabatic couplings) are obtained from full configuration-interaction wavefunctions.

In this Letter we present a measurement of the natural widths of Σ c 0 and Σ c ++ . Using data from the FOCUS experiment, we find Γ ( Σ c 0 )=1.55 +0.41 −0.37 ±0.38 MeV/ c 2 and Γ ( Σ c ++ )=2.05 +0.41 −0.38 ±0.38 MeV/ c 2 . The first errors are statistical, the second systematic. These results are obtained with a sample of 913 Σ c 0 →Λ c + π − decays and 1110 Σ c ++ →Λ c + π + decays. These results are compared with recent theoretical predictions.

The final publication is available at http://link.springer.com/article/10.1140%2Fepjd%2Fe2014-50109-4, We have performed calculations for collisions between fully stripped ions, C6+ and N7+, and atomic hydrogen, in both its ground and first excited energylevels. We have employed the Classical Trajectory Monte Carlo method to obtain total ionization and charge exchange cross sections and state selective charge exchange cross sections in the 5-500 keV/amu energy range., This work has been supported by the projects ENE2007-62934 and ENE2011-28200 of the Secretaría de Estado de Investigación, Desarrollo e Innovación (Spain), and the ADAS-EU Euratom Framework 7 Support Action.

In Mexico, as in other countries, studies do not distinguish between attempted suicide and suicidal and nonsuicidal self-injury (NSSI). The aim of this study was to investigate self-injury and its prevalence using several definitions, in addition to studying the frequency of the proposed DSM-5 criteria for NSSI in adolescent girls and boys.The study was observational, descriptive, cross-sectional, and comparative using a nonrandomized sample of adolescent girls and boys from official high schools who completed the self-injury questionnaire.The participants were 533 older children and adolescents with a mean (SD) age of 13.37 (0.95) years, age range 11 to 17 years, and 54% female sex distribution. The prevalence of NSSI defined according to proposed DSM-5 criteria was 5.6% (N=30) and, according to a broad definition using only item 51 (“Do you hurt yourself without intending to end your life?”), 17.1% (N=140). Prevalence defined by the number of events in the last month (1-3 events) was 9.9% (N=53), in the last 6 months (1-3 events), 11.6% (N=62), and in the last year (5 events), 12.6% (N=67). The age at onset was 11.9 (1.39) years (range 6-15 years). Most DSM-5 criteria were more frequent in girls than boys.Suicidal and nonsuicidal self-injury are frequent in the community. Important points for decision-making in schools and medical practice are discussed.

Diabetic kidney disease (DKD) is the leading cause of ESRD. We conducted an open-label, prospective, randomized trial to determine whether pentoxifylline (PTF), which reduces albuminuria, in addition to renin-angiotensin system (RAS) blockade, can slow progression of renal disease in patients with type 2 diabetes and stages 3-4 CKD. Participants were assigned to receive PTF (1200 mg/d) (n=82) or to a control group (n=87) for 2 years. All patients received similar doses of RAS inhibitors. At study end, eGFR had decreased by a mean±SEM of 2.1±0.4 ml/min per 1.73 m(2) in the PTF group compared with 6.5±0.4 ml/min per 1.73 m(2) in the control group, with a between-group difference of 4.3 ml/min per 1.73 m(2) (95% confidence interval [95% CI], 3.1 to 5.5 ml/min per 1.73 m(2); P

Molecular orbitals are presented in configuration and momentum representations. We propose to minimize large oscillations present in calculated momentum wavefunctions by cancelling position factor phases. We illustrate the distortion introduced by different electron translation factors and show continuum states and dynamical wavefunctions in momentum coordinates. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001

We present cross sections for electron capture in N5++H2 collisions in the energy range 100 eV/amu≤E≤6 keV/amu. We employ a model potential aproximation to treat the interaction of the active electron with the cores, and a recently proposed method, which applies the independent particle model to evaluate the Hamiltonian matrix elements. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001

Using a large sample of photoproduced charm mesons from the FOCUS experiment at Fermilab (FNAL-E831), we observe the decay D0-->K+pi- with a signal yield of 149+/-31 events compared to a similarly cut sample consisting of 36 760+/-195 D0-->K-pi+ events. We use the observed ratio of D0-->K+pi- to D0-->K-pi+ (0.404+/-0.085+/-0.025)% to obtain a relationship between the D0 mixing and doubly Cabibbo suppressed decay parameters.

The microstructure evolution in a Zn–22 wt%Al–2 wt%Cu alloy during aging was followed, using X-ray diffraction, scanning electron microscopy, transmission electron microscopy and field ion microscopy. Samples were solution treated at 623 K for 1 week and then some of them annealed and the others quenched. Both annealed and quenched samples were aged at 373, 423 and 473 K for times from 3.6 (0.04 days) to 1800 ks (20.8 days). The X-ray patterns showed that the η phase decomposed according to the following reaction η→η+α during aging. This was also confirmed by TEM and SEM results, which showed first the spinodal decomposition of the η phase and then the formation of a coarse lamellar structure, composed of the α and η phases. The X-ray analysis of aged samples also showed the occurrence of a four-phase reaction α+ϵ→τ+η. The τ phase was widely recognized in SEM, TEM and FIM results. Additionally, the XRD and TEM results indicated that the formation of the equilibrium ordered τ′ phase is preceded by that of the disordered τ phase.

Interchromosomal distributions of breakpoints from chromatid-type aberrations induced by gamma rays in Chinese hamster ovary (CHO) cells were analyzed. In most chromosomes the distribution was as expected from chromosome lengths for simple breaks or the respective relative corrected length in case of exchanges. There were deviations from expectation in a few chromosomes for chromatid breaks, interchanges, intra-arm intrachanges and inter-arm intrachanges. Especially interesting are the results concerning chromosomes 2 and 8, which were more often involved in exchanges than expected. An "exchange phenotype" for these chromosomes is proposed and possible explanations for the nonrandom distribution of chromosome breakpoints are presented.As distribuições intercromossômicas de pontos de quebra vindos de aberrações tipo cromátide induzidas por raios gama em células de ovário de hamster chinês foram analisadas. Na maioria dos cromossomos a distribuição foi a esperada de comprimentos de cromossomos para quebras simples ou, em caso de trocas, o respectivo comprimento corrigido. Em uns poucos cromossomos, houve desvios a partir do esperado para quebras de cromátides, trocas, trocas dentro do braço e trocas entre braços. Especialmente interessantes foram os resultados relativos aos cromossomos 2 e 8, que se envolveram nas trocas mais freqüentemente do que o esperado. Um "fenótipo de troca" para esses cromossomos é proposto e possíveis explicações para a distribuição não-aleatória de pontos de quebra cromossômicas são apresentadas.

Using a high statistics sample of photoproduced charmed particles from the FOCUS experiment at Fermilab (FNAL-E831), we measure the mass splittings of the charmed baryons Σ c 0 and Σ c ++ . We find M(Σ c 0 −Λ c + ) =167.38 ±0.21 ±0.13 MeV /c 2 and M(Σ c ++ −Λ c + ) =167.35 ±0.19 ±0.12 MeV /c 2 with samples of 362±36 and 461±39 events, respectively. We measure the isospin mass splitting M(Σ c ++ −Σ c 0 ) to be −0.03 ±0.28 ±0.11 MeV /c 2 . The first errors are statistical and the second are systematic.

The vibrational distribution of H2+(X 2Σ+g; ν) after charge transfer in C2+(2s2p; 3P) + H2 collisions is obtained ab initio using the semiclassical eikonal method and the sudden approximation. Results are in good agreement with experiment (Leputsch et al 1997 J. Phys. B: At. Mol. Opt. Phys. 30 5009).

We present cross sections for electron capture in C4+ + H2 collisions in the energy range 50 eV amu-1≤E≤ 6 keV amu-1, calculated using a model potential aproximation to treat the interaction of the active electron with C4+ and H2+ cores and an equivalent-electron bielectronic interpretation of the probabilities. The limitations of this method are analysed by comparison with the two-electron ab initio treatment. Double-electron-capture cross sections are also calculated using ab initio and model potential treatments. We propose a modified independent particle model to evaluate single-electron-capture cross sections.

We evaluate single-capture cross sections in collisions of H+ or Li+ ions with H2 (D2, DT, T2) molecules in a range of impact energies of 50 eV amu-1-6.25 keV amu-1. We present the first theoretical treatment for Li+ projectiles, we extend the energy range of previous treatments for H+ and we test the accuracy of simplified approaches, such as the Franck-Condon approximation and a new angle-averaging procedure. For H+ + H2, a significant enhancement of the capture cross section is predicted when the H2 target is initially in its first excited vibrational state.

We report the evaluation of charge-exchange and spin-change cross sections in C2+ (1 S,3 P)+H reactions at impact energies 0.1-300 keV. Comparison with measured data shows that the effect of contamination of ground state beams by metastable species would only be important for E

The technique of double translational energy spectroscopy has been used for the first time with an atomic hydrogen target. We have carried out measurements of state-selective one-electron capture in 6 keV C2+ -H(1s) collisions which avoid the ambiguities in interpretation of previous experiments and allow separate identification of the collision channels associated with either C2+ (2s2 )1 S ground-state or C2+ (2s2p)3 Po metastable primary ions. In a theoretical counterpart, partial cross sections for both reactions have been calculated using a semiclassical molecular approach. There is good agreement between experiment and calculations.

A partir de las observaciones de una perturbación en el medio interplanetario, se discuten dos posibles fuentes de rayos cósmicos solares: los más energéticos son generados en el propio proceso de origen del destello en Ha asociado a la perturbación, los de menor energía son generados en el frente de onda de la perturbación. Se hace un estimado de la distancia en que se produce la activación del mecanismo de generación en el frente de onda.

We present an analysis of the structure of dynamical couplings in the vicinity of conical intersections between potential energy surfaces that appear in the treatment of electron capture in ion-molecule collisions. While the use of geometrical phases can be avoided, rotational couplings between adiabatic wavefunctions display a non-integrable singularity (a pole) at the conical intersection, so that passage to a more smoothly varying basis is indispensable.

We report total and partial charge transfer cross sections for C4++H collisions in the energy range 0.01-10 keV/amu, calculated using a molecular basis and quantal and semiclassical formalisms. Our total charge transfer cross section does not show the sharp structure found in the experimental measurements of Bliek et al (1997 Phys. Rev. A 56 526) at E400 eV/amu.

Erythropoietin (EPO) deficiency is the main cause of renal anaemia. However, inhibition of erythropoiesis by cytokines such as tumour necrosis factor alpha (TNF-a) may play an important role. The aim of this work was to study the effects of pentoxifylline, an agent with anti-TNF-a properties, on the haematologic status in anaemic patients with advanced renal failure.In a prospective study, 7 anaemic patients with advanced renal disease (creatinine clearance30 ml/min) were treated with pentoxifylline (400 mg orally daily) for 6 months. The evolution of haemoglobin, haematocrit, creatinine clearance and serum EPO and TNF-a a concentrations were compared with those obtained from an untreated control group.Haemoglobin and haematocrit significantly increased in the pentoxifylline-treated patients (9.9+/-0.5 g/dl and 27.9+/-1.6% at baseline; 10.6+/-0.6 g/dl and 31.3+/-1.9% at the 6th month, respectively, p0.01), whereas no variation was seen in the control group. Serum EPO levels remained stable in all patients. However, the serum TNF-a concentration decreased significantly in patients receiving pentoxifylline (basal 623+/-366 pg/ml; 6th month 562+/-358 pg/ml, p0.01), but not in the control group.Our findings suggest that the inhibition of erythropoiesis by cytokines may play a significant role in renal anaemia. The administration of agents with anti-cytokine properties, such as pentoxifylline, can improve the haematologic status in anaemic patients with advanced renal failure.

Dynamical calculations are carried out within the framework of the Frank-Condon approximation, for collisions between H+ and Be4+ ions with H2 molecules within the range of energies . For the higher impact energies, we employ single-particle models, using semiclassical and classical trajectory Monte Carlo adapted methods. The accuracy of the single-particle models is checked by comparing molecular data, transition probabilities and cross sections, with those obtained with an ab initio approach and with experiment. We conclude that a central potential approximation for the H2 molecule yields accurate capture and electron-loss cross sections for , and good ones in the energy region . An analysis of the equivalent and non-equivalent-electrons bielectronic interpretations of the model potential probabilities has been performed; for both reactions, comparison of the Hamiltonian matrix elements in a diabatic representation supports the conclusion that an equivalent-electron picture is adequate to describe the active electron of the H2 molecule with an H2+ `core'.

La enteritis eosinofilica primaria es una entidad infrecuente, caracterizada por infiltracion por eosinofilos de las diferentes capas del intestino delgado. La sintomatologia depende del lugar de la infiltracion y de las capas afectadas. Usualmente se caracteriza por presentar valores elevados de eosinofilos en sangre. La tomografia computarizada desempena un papel fundamental en la valoracion de esta patologia. En este trabajo presentamos un caso diagnosticado en funcion de los datos clinicos, de laboratorio y tomograficos.

Total and n-partial cross sections for charge transfer in collisions are calculated for collision energies between and . A molecular expansion is employed, and semiclassical and quantal calculations are carried out including a common translation factor and a common reaction coordinate, respectively. The comparison between quantal and semiclassical cross sections and transition probabilities is discussed.

With the aim to become a data source to study the influence of different physical conditions on CME phenomenology this catalogue puts together published information on CME and other solar phenomena. The catalogue provides information on the CME itself (SMM and ground observations), on underlying solar features, on Hα flares (including remarks on proton event association), and on solar radio emission outstanding occurrences. When analysing specific cases, users should take the uncertainty on CME to solar phenomena association, due to the observational methods and CME scale, into account. A detailed description of the association criteria is provided for each considered phenomenon.

We present ab initio molecular energies and all dynamical couplings required for a multistate treatment of charge transfer in the reaction of Be4+ ions with H2 molecules in the range of 50 eV amu−1 to 1 keV amu−1. Vibrationally resolved partial cross sections are given.

While studying CME phenomenology the existence of different physical conditions were considered. These conditions are roughly described by the CME association to different solar active phenomena. We considered three different typical locations in which CME and associated solar activity may occur; in sunspots, plages and the large scale magnetic field pattern, which has not been included earlier. No matter the large uncertainty of the CME association to solar features, due to the observational method and the CME scale; from data exploration some tendencies were obtained and discussed. No evidence was found that the process that leads to coronal mass ejections starts before their detection at 1.6 solar radii. This indicates that the whole volume moves upward simultaneously, no matter how deep it reaches into the solar atmosphere.

We describe an implementation of the vibro-rotational sudden approximation eikonal (SEIKON) method to treat collisions between ions (atoms) and diatomic molecules at impact energies such that a semiclassical eikonal approximation can be applied to treat the relative motion of the colliding species, and a close-coupling molecular expansion is able to accurately represent electronic transitions. Our method, which does not make use of Franck - Condon-type approximations, allows us to evaluate vibrationally resolved charge-transfer and excitation cross sections, as well as total cross sections for transitions to the vibrational continuum. The implementation is illustrated with calculations of cross sections for single-charge transfer, vibrational excitation, and transfer dissociation in , and DT collisions. The validity of the Franck - Condon approximation for these reactions is studied.

We report on the results of a search for fourteen flavor changing neutral current, lepton number violating, or lepton family number violating decays of the charmed meson D + in the large charm sample recorded by the Fermilab photoproduction experiment E687. No evidence is seen for these rare and standard-model-forbidden decays, of the form D + → h ± l ∓ l + (with h = π , K and l = e , μ ); we determine 90% confidence level upper limits on their absolute branching fractions in the range (9–20) × 10 −5 .

The observation that some subjects with low PTH had elevated plasma magnesium (Mg) levels prompted us to analyze in 41 patients on maintenance hemodialysis for 44 +/- 36 months, their serum Mg concentrations, and the relationship between plasma Mg and PTH levels. The mean serum Mg concentration was 2.4 +/- 0.2 mg/dl. Twenty-four out of the 41 subjects (58.5%) had hypermagnesemia (serum Mg above 2.5 mg/dl). Patients were classified into 3 groups according to their PTH level: Group A, low PTH (below 120 pg/ml); group B, adequate PTH (120-250 pg/ml); and group C, high PTH (above 250 pg/ml). There were no differences among groups according to number of subjects, age, sex, time on dialysis, renal disease, serum calcium, phosphorus, bicarbonate, vitamin D or aluminum concentrations. Doses of calcium carbonate and aluminium hydroxide were also similar in all groups. Curiously, although the differences were not statistically significant, the total cumulative intake of calcium and aluminium were less in group A than in the other groups. Interestingly, patients with low PTH had a significantly higher serum Mg concentration than patients with adequate or high PTH (2.8 +/- 0.2 mg/dl vs 2.3 +/- 0.1 mg/dl and 2.2 +/- 0.1 mg/dl, respectively, p0.01). Moreover, regression analysis showed a negative linear correlation between serum PTH level and plasma Mg concentration (r = -0.6059, p0.001). Based on these findings, chronic hypermagnesemia could have a suppressive effect on PTH secretion, and it could be a risk factor for the development of adynamic bone disease in dialysis patients.

The existence of three magnetic scenarios with magnetic field intensities one order apart was considered. CMEs were associated to different solar activity phenomena and solar features showing different characteristics. Those associated to intense magnetic fields were more complex, having either more components or multiple emissions and a greater magnetic energy to particle acceleration conversion rate. On the other hand, simple CMEs were found to associate to weak magnetic fields. No evidence was found that the process that leads to CME starts before their detection at 1.6 solar radii. This indicates that the whole volume moves upward simultaneously, no matter how deep it reaches into the solar atmosphere.

There is no consensus on the magnitude and shape of the charge transfer cross section in low-energy H^+ + H_2 collisions, in spite of the fundamental importance of these collisions. Experiments have thus been carried out in the energy range 15 ≤ E ≤ 5000 eV. The measurements invalidate previous recommended data for E ≤ 200 eV and confirm the existence of a local maximum around 45 eV, which was predicted theoretically. Additionally, vibrationally resolved cross sections allow us to investigate the evolution of the underlying charge transfer mechanism as a function of E.