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This study focused on the assessment and quantification of discards generated by clam fisheries along the northern Alboran Sea (western Mediterranean). Discard samples (n= 278) were collected throughout one year on board nine commercial vessels. A total of 129 species were identified, mostly represented by molluscs (72 spp.), arthropods (20 spp.) and echinoderms (12 spp.). Molluscs dominated in terms of abundance (67.5%) and biomass (94.2%). The superfamily Paguroidea (i.e. hermit crabs), together with undersized target individuals, were the most abundant taxa. The abundance and biomass of discards displayed significant maximum values in winter, which could be partly related to biotic factors including population dynamics of some dominant species. Multivariate analyses indicated the presence of different assemblages related to the targeted bivalve species, reflecting the transition between a fine surface-sands biocoenosis exposed to wave action and a well-sorted fine sands biocoenosis below 5 m depth. Analysis of biogeographical affinities showed that most discarded species (73.2%) have an extensive Atlantic range, whereas 7.1% have a restricted distribution within the Mediterranean. The presence of subtropical species highlights the uniqueness of this area (the Atlantic–Mediterranean transition) in European seas. The usefulness of discard analysis for biodiversity assessment is discussed.

Se presenta el caso de una mujer de 46 años de edad sin antecedentes de interés quien, tras una intervención de histerectomía abdominal con anestesia raquídea, presentó en el postoperatorio hipoestesia en la cara anterior del muslo, paresia cuadricipital y abolición del reflejo rotuliano, sin otras manifestaciones asociadas. Inicialmente dicho cuadro clínico fue achacado a la técnica anestésica. Sin embargo, las exploraciones complementarias posteriores llevadas a cabo con tomografía computarizada, resonancia magnética y electromiografía descartaron que la técnica anestésica fuera la responsable del cuadro clínico que presentaba la paciente, que fue diagnosticada de neuropatía femoral secundaria a la técnica quirúrgica realizada. Como resultado, la evolución del cuadro clínico fue satisfactoria. Dicha clínica cedió al cabo de 6 meses de tratamiento rehabilitador y de la administración oral de complejo vitamínico B.

En descompensaciones por insuficiencia cardiaca (IC), tanto el daño renal agudo (DRA) como los niveles elevados de galectina-3 (Gal-3) se han asociado con una peor evolución. Los niveles plasmáticos de Gal-3 se ven influidos por la función renal; sin embargo, el posible papel de la Gal-3 como predictor de DRA no está establecido.

El síndrome de Kearns-Sayre constituye una miopatía mitocondrial que cursa con oftalmoplejia, retinopatía pigmentaria y alteraciones de la conducción cardiaca. Presentamos el caso de un paciente de 50 años de edad con síndrome de Kearns-Sayre intervenido de una fractura de fémur con anestesia subaracnoidea.

Treatment outcome in older patients with acute promyelocytic leukemia (APL) is lower compared with younger patients, mainly because of a higher induction death rate and postremission non-relapse mortality (NRM). This prompted us to design a risk- and age-adapted protocol (Programa Español de Tratamientos en Hematología (PETHEMA)/HOVON LPA2005), with dose reduction of consolidation chemotherapy. Patients aged ⩾60 years reported to the PETHEMA registry and were treated with all-trans retinoic acid (ATRA) plus anthracycline-based regimens according to three consecutive PETHEMA trials that were included. We compared the long-term outcomes of the LPA2005 trial with the preceding PETHEMA trials using non-age-adapted schedules (LPA96&LPA99). From 1996 to 2012, 389 older patients were registered, of whom 268 patients (69%) were eligible. Causes of ineligibility were secondary APL (19%), and unfit for chemotherapy (11%). Median age was 67 years, without relevant differences between LPA2005 and LPA96&LPA99 cohorts. Overall, 216 patients (81%) achieved complete remission with no differences between trials. The 5-year NRM, cumulative incidence of relapse, disease-free survival and overall survival in the LPA2005 vs the LPA96&99 were 5 vs 18% (P=0.15), 7 vs 12% (P=0.23), 87 vs 69% (P=0.04) and 74 vs 60% (P=0.06). A less intensive front-line regimen with ATRA and anthracycline monochemotherapy resulted in improved outcomes in older APL patients.

Objectives:High-resolution manometry (HRM) is the preferred method for the evaluation of motility disorders. Recently, an update of the diagnostic criteria (Chicago 3.0) has been published. The aim of this study was to compare the performance criteria of Chicago version 2.0 (CC2.0) vs. 3.0 (CC3.0) in a cohort of healthy volunteers and symptomatic patients.Methods:HRM studies of asymptomatic and symptomatic individuals from several centers of Spain and Latin America were analyzed using both CC2.0 and CC3.0. The final diagnosis was grouped into hierarchical categories: obstruction (achalasia and gastro-esophageal junction obstruction), major disorders (distal esophageal spasm, absent peristalsis, and jackhammer), minor disorders (failed frequent peristalsis, weak peristalsis with small or large defects, ineffective esophageal motility, fragmented peristalsis, rapid contractile with normal latency and hypertensive peristalsis) and normal. The results were compared using McNemar’s and Kappa tests.Results:HRM was analyzed in 107 healthy volunteers (53.3% female; 18–69 years) and 400 symptomatic patients (58.5% female; 18–90 years). In healthy volunteers, using CC2.0 and CC3.0, obstructive disorders were diagnosed in 7.5% and 5.6%, respectively, major disorders in 1% and 2.8%, respectively, minor disorders in 25.2% and 15%, respectively, and normal in 66.4% and 76.6%, respectively. In symptomatic individuals, using CC2.0 and CC3.0, obstructive disorders were diagnosed in 11% and 11.3%, respectively, major disorders in 14% and 14%, respectively, minor disorders in 33.3% and 24.5%, respectively, and normal in 41.8% and 50.3%, respectively. In both groups of individuals, only an increase in normal and a decrease in minor findings using CC3.0 were statistically significant using McNemar’s test.Discussions:CC3.0 increases the number of normal studies when compared with CC2.0, essentially at the expense of fewer minor disorders, with no significant differences in major or obstructive disorders. As the relevance of minor disorders is questionable, our data suggest that CC3.0 increases the relevance of abnormal results.

The safety and efficacy of a 4-day myeloablative conditioning (MAC) regimen consisting of Bu 3.2 mg/kg and fludarabine 40 mg/m2/day for HLA-identical sibling allogeneic hematopoietic cell transplantation (HCT) in myeloid malignancies was investigated in 133 patients (median age, 47 years; range 19–74 years) with de novoAML (60%), secondary AML (20%) or myelodysplastic syndrome (20%). All patients engrafted. Hepatic veno-occlusive disease occurred in five patients (4%), and severe toxicities, mostly mucositis, occurred in twenty-three (17%) patients. The non-relapse mortality (NRM) at 100 days was 1.5%. The incidences of acute GVHD grade 2–4 and grade 3–4 were 32 and 13%, respectively. At a median follow-up of 38 months, the cumulative incidence of chronic GVHD was 67%. The relapse incidence was 30% (27 and 31%, respectively, in patients with early- and late-stage disease), and the overall NRM was 15%. The actuarial 4-year disease-free survival (DFS) and overall survival (OS) were 54 and 62%, respectively. Patients aged <50 years had better outcomes compared with older patients (DFS 64 vs 42%, P=0.006; OS 73 vs 47%, P<0.001, respectively).

An experimental work on transitional separation bubbles is presented. The bubbles are generated on a flat plate by imposing, at some distance from the plate's leading edge, a region with a constant inviscid flow deceleration. Wall pressure, pitot-static probes, hot-wire, PIV, and LDV anemometry measurements are conducted to characterize the flow evolution. The different regions of the separation bubbles are studied and scaling laws are proposed to quantify the laminar shear layer length, its angle with the wall, the characteristic most amplified frequency, and the amplification rate during the linear stages of the transitional phenomena. The reattachment of the flow is found to be related to the evolution of the large scale structure after the shear layer rolls up. Downstream from reattachment, the velocity profile at the turbulent boundary layer seems to scale to a self-similar form.

The main components of Lavender and Lavandin essential oils are linalyl acetate and linalool. An enrichment of the product in linalyl acetate is of interest, since the market value of this component is considerably higher than that of linalool. This work presents a thermodynamic study of the synthesis of linalyl acetate from linalool by a catalytic transesterification with ethyl acetate in a supercritical CO2medium. The study comprises the calculation of the equilibrium compositions of this reaction, and the correlation to the fluid phase equilibrium of this system, which is of interest for the determination of the maximum concentration of reagents during the reaction, and for the study of the fractionation of the reaction products. The nonideal behavior of the system is accounted for by using the Stryjek‐Vera Peng‐Robinson Equation of State (PRSV EoS). The results are used to select optimum conditions for an experimental study of this reaction.

Programmed cell death is an established developmental process in the nervous system. Whereas the regulation and the developmental role of neuronal cell death have been widely demonstrated, the relevance of cell death during early neurogenesis, the cells affected and the identity of regulatory local growth factors remain poorly characterized. We have previously described specific in vivo patterns of apoptosis during early retinal neurogenesis, and that exogenous insulin acts as survival factor (Díaz, B., Pimentel, B., De Pablo, F. and de la Rosa, E. J. (1999) Eur. J. Neurosci. 11, 1624-1632). Proinsulin mRNA was found to be expressed broadly in the early embryonic chick retina, and decreased later between days 6 and 8 of embryonic development, when there was increased expression of insulin-like growth factor I mRNA, absent or very scarce at earlier stages. Consequently, we studied whether proinsulin and/or insulin ((pro)insulin) action in prevention of cell death has physiological relevance during early neural development. In ovo treatment at day 2 of embryonic development with specific antibodies against (pro)insulin or the insulin receptor induced apoptosis in the neuroretina. The distribution of apoptotic cells two days after the blockade was similar to naturally occurring cell death, as visualized by TdT-mediated dUTP nick end labeling. The apoptosis induced by the insulin receptor blockade preferentially affected to the Islet1/2 positive cells, that is, the differentiated retinal ganglion cells. In parallel, the insulin survival effect on cultured retinas correlated with the activation of Akt to a greater extent than with the activation of MAP kinase. These results suggest that the physiological cell death occurring in early stages of retinal development is regulated by locally produced (pro)insulin through the activation of the Akt survival pathway.

The evolution of the intensity profile of TEA CO2laser pulses along the pulse length is investigated both analytically and experimentally. A simple scalar model of the pulse amplitude is introduced, which gives the loaded-cavity modes as a linear combination of bidimensional Hermite-Gauss functions. According to this model a number of equations are derived which link the time-varying spatial structure of the pulse to its time-resolved second-order intensity moments, namely, the beam width and the M2parameter.

Formaldehyde has been known for many years as an indoor air pollutant coming from different pieces of furniture and panels in the rooms.A study of the concentrations of formaldehyde in the air of sixty selected structures panelled with urea-formaldehyde resins was carried out in Spain. Air samples were collected in impingers and analyzed by 3-Methyl-2 Benzothiazolone-hydrazone-hydrochloride tests (M.B.T.H.) during the year 1984.The average concentration of formaldehyde was 552 μg/m3 with a range of 41-2823 mg/m3. Thirty-nine homes were found to have concentrations exceeding the average value. These concentrations are higher than allowed indoor exposure standard.Health information was received by direct contact from individuals. Eye irritation, dry or sore throat, mucous membrane irritation, burning eyes, sneeze, runny nose, rash, cough, conjunctivitis, difficult breathing, pharyngytis, bronchitis, headache, weakness, vomiting, nausea, photophobia ... were the most frequent symptoms reported by the occupants.A complementary study was carried out using information on type of structure, age and heating systems of the building.Statistically significant relationship was observed between formaldehyde concentration and health data and between formaldehyde levels and installation age of panels in the structures.

Summary We give a rigorous proof of the validity of the Lax equivalence theorem when the true solution at timet and its approximation lie in different spaces, thus modelling the practical situation where the former is a function of the space variables and the latter is only defined at grid points.

Summary It is known that certain Runge-Kutta methods share the property that, in a constant-step implementation, if a solution trajectory converges to a bounded limit then it must be a fixed point of the underlying differential system. Such methods are calledregular. In the present paper we provide a recursive test to check whether given method is regular. Moreover, by examining solution trajectories of linear equations, we prove that the order of ans-stage regular method may not exceed 2[(s+2)/2] and that the maximal order of regular Runge-Kutta method with an irreducible stability function is 4.

Summary The “good” Boussinesq equationutt=-uxxxx+uxx+(u2)xx has recently been found to possess an interesting soliton-interaction mechanism. In this paper we study the nonlinear stability and the convergence of some simple finite-difference schemes for the numerical solution of problems involving the “good” Boussinesq equation. Numerical experimentas are also reported.

Summary A trajectory problem is an initial value problemdy/dt=f(y),y(0)=? where the interest lies in obtaining the curve traced by the solution (the trajectory), rather than in finding the actual correspondanc between values of the parametert and points on that curve. We prove the convergence of the Lambert-McLeod scheme for the numerical integration of trajectory problems. We also study the CELF method, an explicit procedure for the integration in time of semidiscretizations of PDEs which has some useful conservation properties. The proofs rely on the concept of restricted stability introduced by Stetter. In order to show the convergence of the methods, an idea of Strang is also employed, whereby the numerical solution is compared with a suitable perturbation of the theoretical solution, rather than with the theoretical solution itself.

Summary We consider the question of whether multistep methods inherit in some sense quadratic first integrals possessed by the differential system being integrated. We also investigate whether, in the integration of Hamiltonian systems, multistep methods conserve the symplectic structure of the phase space.

We show that, when numerically integrating Hamiltonian problems, nondissipative numerical methods do not in general share the advantages possessed by symplectic integrators. Here a numerical method is called nondissipative if, when applied with a small stepsize to the test equationdy/dt = i?y, ? real, has amplification factors of unit modulus. We construct a fourth order, nondissipative, explicit Runge-Kutta-Nyström procedure with small error constants. Numerical experiments show that this scheme does not perform efficiently in the numerical integration of Hamiltonian problems.

We are concerned with Runge-Kutta-Nyström methods for the integration of second order systems of the special formd2y/dt2=f(y). If the functionf is the gradient of a scalar field, then the system is Hamiltonian and it may be advantageous to integrate it by a so-called canonical Runge-Kutta-Nyström formula. We show that the equations that must be imposed on the coefficients of the method to ensure canonicity are simplifying assumptions that lower the number of independent order conditions. We count the number of order conditions, both for general and for canonical Runge-Kutta-Nyström formulae.

Separable Hamiltonian systems of differential equations have the form $ d{\mathbf{p}}/dt = - \partial H/\partial {\mathbf{q}}$ $ d{\mathbf{q}}/dt = \partial H/\partial {\mathbf{p}}$H that satisfies $ H = T({\mathbf{p}}) + V({\mathbf{q}})$T and V are respectively the kinetic and potential energies). We study the integration of these systems by means of partitioned Runge-Kutta methods, i.e., by means of methods where different Runge-Kutta tableaux are used for the p and q equations. We derive a sufficient and "almost" necessary condition for a partitioned Runge-Kutta method to be canonical, i.e., to conserve the symplectic structure of phase space, thereby reproducing the qualitative properties of the Hamiltonian dynamics. We show that the requirement of canonicity operates as a simplifying assumption for the study of the order conditions of the method.

Nucleation of bismuth on TGS single crystals has been studied at different temperatures showing unlike characteristics above and below Tc. Decoration figures which may be ascribed to ferroelectric domains are observed at low temperatures. Moreover, Doppler broadening curves have been recorded and a sharp change in the positron behaviour is also noticed at Tc.

The orientation of a general partially coherent beam is described by introducing two pairs of orthogonal axes defined in terms of the second-order coherence features of the field. A general classification scheme for light beams is presented, based on their rotational behaviour under free propagation. This behaviour could be inferred from the values of certain measurable parameters at some plane. As an example of interest, the above classification is applied to Gaussian (coherent) beams with general astigmatism.

An analytic and measurable beam parameter is defined for beams emerging from heterojunction monomode diode lasers with very thin active layers, which provides a joint description of their focusing capabilities and far field divergence behaviour. This parameter can be of use as a figure of merit to compare either the output responses of this type of laser or the different optical systems employed to modify the laser beam. The minimum value of this parameter is determined. Also, it is shown that the beams emitted by these lasers cannot be transformed into circularly symmetric ones by anyABCD optical system. Finally, the possibility of achieving circularly symmetric intensities (at least to second order) and/or beam collimation at some plane is investigated, and its connection with the coupling efficiency between a monomode diode laser and an optical fibre is pointed out.

A sufficient condition for the symplecticness ofq-derivative Runge-Kutta methods has been derived by F. M. Lasagni. In the present note we prove that this condition can only be satisfied for methods withq≤1, i.e., for standard Runge-Kutta methods. We further show that the conditions of Lasagni are also necessary for symplecticness so that no symplectic multi-derivative Runge-Kutta method can exist.

We study the application of Runge-Kutta schemes to Hamiltonian systems of ordinary differential equations. We investigate which schemes possess the canonical property of the Hamiltonian flow. We also consider the issue of exact conservation in the time-discretization of the continuous invariants of motion.

The boundary locus method for determining the stability region of a linear multistep method is considered from several viewpoints. In particular we show how it is related to the order of the method. These ideas are extended to Runge-Kutta and other methods.

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Within the formalism of the Wigner distribution function, a new parameter is proposed, which characterizes arbitrary tridimensional partially coherent beams and is invariant through ABCD optical systems. The relationship between such a parameter and the bidimensional concept of beam quality is analyzed. An absolute lower bound that the new parameter can reach is also shown.

The quality behaviour of Gaussian Schell-model fields propagating through general (non-orthogonal) ABCD optical systems has been characterized by introducing a number of parameters. Such parameters have been given in terms of the Wigner distribution function of the field, closely connected with its second-order coherence features. Dependence of the focusing capabilities, transversal widths and beam asymmetry on the coherence length of the field has been investigated.

All trans-retinoic acid (ATRA) syndrome is a life-threatening complication of uncertain pathogenesis that can occur during the treatment of acute promyelocytic leukemia (APL) by ATRA. Since its initial description, however, no large series of ATRA syndrome has been reported in detail. We analyzed cases of ATRA syndrome observed in an ongoing European trial of treatment of newly diagnosed APL. In this trial, patients 65 years of age or less with an initial white blood cell count (WBC) less than 5,000/µL were initially randomized between ATRA followed by chemotherapy (CT) (ATRA?CT group) or ATRA with CT started on day 3; patients with WBC greater than 5,000/µL received ATRA and CT from day 1; patients aged 66 to 75 received ATRA?CT. In patients with initial WBC less than 5,000/µL and allocated to ATRA?CT, CT was rapidly added if WBC was greater than 6,000, 10,000, 15,000/µL by days 5, 10, and 15 of ATRA treatment. A total of 64 (15%) of the 413 patients included in this trial experienced ATRA syndrome during induction treatment. Clinical signs developed after a median of 7 days (range, 0 to 35 days). In two of them, they were in fact present before the onset of ATRA. In 11 patients, they occurred upon recovery from the phase of aplasia due to the addition of CT. Respiratory distress (89% of the patients), fever (81%), pulmonary infiltrates (81%), weight gain (50%), pleural effusion (47%), renal failure (39%), pericardial effusion (19%), cardiac failure (17%), and hypotension (12%) were the main clinical signs, and 63 of the 64 patients had at least three of them. Thirteen patients required mechanical ventilation and two dialysis. A total of 60 patients received CT in addition to ATRA as per protocol or based on increasing WBC; 58 also received high dose dexamethasone (DXM); ATRA was stopped when clinical signs developed in 30 patients. A total of 55 patients (86%) who experienced ATRA syndrome achieved complete remission (CR), as compared with 94% of patients who had no ATRA syndrome (P= .07) and nine (14%) died of ATRA syndrome (5 cases), sepsis (2 cases), leukemic resistance (1 patient), and central nervous system (CNS) bleeding (1 patient). None of the patients who achieved CR and received ATRA for maintenance had ATRA syndrome recurrence. No significant predictive factors of ATRA syndrome, including pretreatment WBC, could be found. Kaplan Meier estimates of relapse, event-free survival (EFS), and survival at 2 years were 32% ± 10%, 63% ± 8%, and 68% ± 7% in patients who had ATRA syndrome as compared with 15% ± 3%, 77% ± 2%, and 80% ± 2% in patients who had no ATRA syndrome (P= .05, P = .003, and P = .03), respectively. In a stepwise Cox model that also included pretreatment prognostic variables, ATRA syndrome remained predictive for EFS and survival. In conclusion, in this multicenter trial where CT was rapidly added to ATRA in case of high or increasing WBC counts and DXM generally also used at the earliest clinical sign, the incidence of ATRA syndrome was 15%, but ATRA syndrome was responsible for death in only 1.2% of the total number of patients treated. However, occurrence of ATRA syndrome was associated with lower EFS and survival. © 1998 by The American Society of Hematology.

Optimal rates of convergence are established for several fully-discrete schemes for the numerical solution of the nonlinear Schroedinger equation. Both finite differences and finite elements are considered for the discretization in space, while the integration in time is treated either by the leap-frog technique or by a modified Crank-Nicolson procedure, which generalizes the one suggested by Delfour, Fortin and Payne and possesses two useful conserved quantities.

The Lax-Richtmyer theorem is extended to work in the framework of Stetter's theory of discretizations. The new result applies to both initial and boundary value problems discretized by finite elements, finite differences, etc. Several examples are given, together with a comparison with other available equivalence theorems. The proof relies on a generalized Banach-Steinhaus theorem.

The periodic initial value problem for the partial differential equation $ {u_t} + {u_{xxx}} + \beta {({u^2})_x} + \frac{\gamma }{2}{({u^2})_{xx}} + \varepsilon {u_{xx}} - \delta {u_{tx}} = 0$ $ \varepsilon $ 0$ --> $ \delta > 0$ .

We analyze the use of a five-point difference formula for the discretization of the third derivative operator on nonuniform grids. The formula was derived so as to coincide with the standard five-point formula on regular grids and to lead to skew-symmetric schemes. It is shown that, under periodic boundary conditions, the formula is supraconvergent in the sense that, in spite of being inconsistent, it gives rise to schemes with second-order convergence. However, such a supraconvergence only takes place when the number of points in the grid is odd: for grids with an even number of points the inconsistency of the formula results in lack of convergence. Both stationary and evolutionary problems are considered and the analysis is backed by numerical experiments.

We prove the nonlinear stability and convergence of a fully discrete, pseudospectral scheme for the "good" Boussinesq equation . Numerical comparisons with finite difference schemes are also reported.

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Summary We address the question of convergence of fully discrete Runge-Kutta approximations. We prove that, under certain conditions, the order in time of the fully discrete scheme equals the conventional order of the Runge-Kutta formula being used. However, these conditions, which are necessary for the result to hold, are not natural. As a result, in many problems the order in time will be strictly smaller than the conventional one, a phenomenon called order reduction. This phenomenon is extensively discussed, both analytically and numerically. As distinct from earlier contributions we here treat explicit Runge-Kutta schemes. Although our results are valid for both parabolic and hyperbolic problems, the examples we present are therefore taken from the hyperbolic field, as it is in this area that explicit discretizations are most appealing.

The influence of super-Gaussian apertures on the beam power, beam size, beam quality factor and kurtosis parameter of Hermite-Gauss mode beams and Gauss Schell-model fields is investigated in detail.

Many existing numerical schemes for evolutionary problems in partial differential equations (PDEs) can be viewed as method of lines (MOL) schemes. This paper treats the convergence of one-step MOL schemes. Our main purpose is to set up a general framework for a convergence analysis applicable to nonlinear problems. The stability materials for this framework are taken from the field of nonlinear stiff ODEs. In this connection, important concepts are the logarithmic matrix norm and C-stability. A nonlinear parabolic equation and the cubic Schrödinger equation are used for illustrating the ideas.