Urban green spaces and childhood leukemia incidence: A population-based case-control study in Madrid.

BACKGROUND: Childhood leukemia is the most common childhood cancer. To date, few risk factors related to predisposition have been identified; therefore, new hypotheses should be considered. OBJECTIVE: To explore the possible relationship of residential proximity to urban green spaces on childhood leukemia. METHODS: We conducted a population-based case control study in the metropolitan area of Madrid from 2000 to 2015. It included 383 incident cases and 1935 controls, individually matched by birth year, sex and area of residence. Using the geographical coordinates of the participants' home residences, we built a proxy for exposure with four distances (250 m, 500 m, 750 m and 1 km) to urban parks (UPs) and urban wooded areas (UWAs). We employed logistic regression models to determinate the effect of them on childhood leukemia adjusting for environmental and socio-demographic covariates. RESULTS: we found a reduction in childhood leukemia incidence at a distance of 250 m from UPs (OR = 0.78; 95%CI = 0.62-0.98), as well as a reduction of the incidence in the Q3 and Q4 quintiles for exposure to UWAs, in the 250 m and 500 m buffers respectively (Q3 (250 m): OR = 0.69; 95%CI = 0.48-1.00; and, Q4 (500 m): OR = 0.69; 95%CI = 0.48-0.99). CONCLUSIONS: Our results suggest a possible association between lower incidence of childhood leukemia and proximity to different forms of urban green space. This study is a first approach to the possible urban green space effects on childhood leukemia so is necessary to continue studying this spaces taking into account more individual data and other environmental risk factors.

New insights into human farnesyl pyrophosphate synthase inhibition by second-generation bisphosphonate drugs.

Pamidronate, alendronate, APHBP and neridronate are a group of drugs, known as second-generation bisphosphonates (2G-BPs), commonly used in the treatment of bone-resorption disorders, and recently their use has been related to some collateral side effects. The therapeutic activity of 2G-BPs is related to the inhibition of the human Farnesyl Pyrophosphate Synthase (hFPPS). Available inhibitory activity values show that 2G-BPs act time-dependently, showing big differences in their initial inhibitory activities but similar final IC50 values. However, there is a lack of information explaining this similar final inhibitory potency. Although different residues have been identified in the stabilization of the R2 side chain of 2G-BPs into the active site, similar free binding energies were obtained that highlighted a similar stability of the ternary complexes, which in turns justified the similar IC50 values reported. Free binding energy calculations also demonstrated that the union of 2G-BPs to the active site were 38 to 54 kcal mol-1 energetically more favourable than the union of the natural substrate, which is the basis of the inhibition potency of the hFPPS activity.

Ion Acceleration Using Relativistic Pulse Shaping in Near-Critical-Density Plasmas.

Ultraintense laser pulses with a few-cycle rising edge are ideally suited to accelerating ions from ultrathin foils, and achieving such pulses in practice represents a formidable challenge. We show that such pulses can be obtained using sufficiently strong and well-controlled relativistic nonlinearities in spatially well-defined near-critical-density plasmas. The resulting ultraintense pulses with an extremely steep rising edge give rise to significantly enhanced carbon ion energies consistent with a transition to radiation pressure acceleration.

Partition of Omega-like facility into two configurations of 24 and 36 laser beams to improve implosion performance.

An Omega-like beam configuration is considered where the 60-beam layout can be separated into two independent sub-configurations with 24 and 36 laser beams, each minimizing direct drive illumination non-uniformity. Two different laser focal spot profiles, one associated with each configuration, are proposed to apply the zooming technique in order to increase the laser-target coupling efficiency. This approach is used by 1D hydrodynamics simulations of the implosion of a direct-drive capsule characterized by a relatively large aspect ratio A = 7 and an optimized laser pulse shape delivering a maximum of 30 TW and 30 kJ, with different temporal pulse shapes in each of the two sets of beams. It is shown that zooming allows for an optimistic 1D thermonuclear energy gain greater than one while without zooming the thermonuclear gain remains largely below one. While this is incompatible with the as-built Omega laser, it provides a promising option for a future intermediate-energy direct drive laser system.

Space-time pattern of hepatitis A in Spain, 1997-2007.

In Spain hepatitis A is a compulsory notifiable disease and individual cases are reported to the national epidemiological surveillance network. Incidence rates show variations in different regions. The aim of this study was to analyse the space-time pattern of hepatitis A risk at municipal level in Spain and at global and local levels during the period 1997-2007. At global level we used two estimates of risk: the standardized incidence ratio (SIR) and the posterior probability that the smoothed relative risk is >1 (PP). At local level we used the scan statistic method to analyse the space-time clusters. The SIR and significant PP (>0·8) showed the highest risk concentrated in areas of the Mediterranean coast. The most likely cluster gave a relative risk of 53·530. These spatial statistics methodologies can be complementary tools in the epidemiological surveillance of infectious diseases.

Magnetically guided fast electrons in cylindrically compressed matter.

Fast electrons produced by a 10 ps, 160 J laser pulse through laser-compressed plastic cylinders are studied experimentally and numerically in the context of fast ignition. K(α)-emission images reveal a collimated or scattered electron beam depending on the initial density and the compression timing. A numerical transport model shows that implosion-driven electrical resistivity gradients induce strong magnetic fields able to guide the electrons. The good agreement with measured beam sizes provides the first experimental evidence for fast-electron magnetic collimation in laser-compressed matter.

Factors of prognostic value in long-term survival of colorectal cancer patients.

We have studied 191 protocolized colorectal cancer patients, analyzing the prognostic factors described in the literature as being important to long-term survival. Of the data studied, sex, age, duration of symptoms, tumor location, tumor extension within the circumference of the bowel lumen, and the surgical technique employed, all showed differences in terms of five-year survival, but without reaching statistical significance. The factors with statistically significant prognostic value were first symptoms, occlusion, perforation, primary tumor size and configuration, lymph node involvement, degree of wall infiltration, presence of emboli, degree of differentiation and Scarff index. In view of these results, we consider that the evaluation of bowel wall infiltration, lymph node involvement, venous and/or lymphatic embolization, and tumor differentiation is necessary to establish long-term prognosis in these patients. The remaining factors lack prognostic value.

Role of target material in proton acceleration from thin foils irradiated by ultrashort laser pulses.

We report on the proton acceleration studies from thin metallic foils of varying atomic number (Z) and thicknesses, investigated using a 45 fs, 10 TW Ti:sapphire laser system. An optimum foil thickness was observed for efficient proton acceleration for our laser conditions, dictated by the laser ASE prepulse and hot electron propagation behavior inside the material. The hydrodynamic simulations for ASE prepulse support the experimental observation. The observed maximum proton energy at different thicknesses for a given element is in good agreement with the reported scaling laws. The results with foils of different atomic number Z suggest that a judicious choice of the foil material can enhance the proton acceleration efficiency, resulting into higher proton energy.

Spatio-temporal analysis of tuberculosis in Spain, 2008-2010.

BACKGROUND: The characteristics of respiratory tuberculosis (TB) favour the appearance of clusters of cases in space and time. It is important for public health authorities to know which clusters occur randomly and which merit further investigation. OBJECTIVE: To detect spatial and spatio-temporal clusters of respiratory TB in Spain during the period from 1 January 2008 to 31 December 2010. MATERIALS AND METHODS: Retrospective spatio-temporal study of respiratory TB cases reported to Spain's National Epidemiological Surveillance Network from 2008 to 2010, at a municipal level. We used the purely spatial and space-time Scan statistic estimators. All analyses were adjusted for age and sex. RESULTS: The spatial cluster analysis detected 28 significant clusters and the spatio-temporal cluster analysis detected 20 significant clusters. The most likely spatial cluster comprised seven municipalities in the Greater Barcelona Area. Most space-time clusters were situated in the same area, and were detected between 1 April 2008 and 31 March 2009. CONCLUSION: The distribution of TB clusters as shown by the proposed models furnishes a spatial pattern of the distribution of the disease. The two methods used can be a useful tool for analysing the distribution of respiratory TB in Spain.

Laser-driven shock acceleration of ion beams from spherical mass-limited targets.

We report on experimental studies of ion acceleration from spherical targets of diameter 15 microm irradiated by ultraintense (1x10(20) W/cm2) pulses from a 20-TW Ti:sapphire laser system. A highly directed proton beam with plateau-shaped spectrum extending to energies up to 8 MeV is observed in the laser propagation direction. This beam arises from acceleration in a converging shock launched by the laser, which is confirmed by 3-dimensional particle-in-cell simulations. The temporal evolution of the shock-front curvature shows excellent agreement with a two-dimensional radiation pressure model.

Thermal x-ray emission from ion-beam-heated matter.

The conversion of ion beam energy into thermal x-ray radiation by means of stretched cylindrical plasma volumes is studied by analytic modeling and numerical simulation. The analysis is restricted to one-dimensional radiation hydrodynamics. Scaling relations for different materials are derived. Due to equation-of-state properties, high-Z material turns out superior for achieving high conversion efficiency. The paper provides practical answers for thermal x-ray generation with intense heavy ion beams. Deposition powers in the order of 10l6 W/g are required for applications to ion beam inertial confinement fusion.

Nonlinear theory of the ablative Rayleigh-Taylor instability.

A fully nonlinear sharp-boundary model of the ablative Rayleigh-Taylor instability is derived and closed in a similar way to the self-consistent closure of the linear theory. It contains the stabilizing effect of ablation and accurately reproduces the results of 2D DRACO simulations. The single-mode saturation amplitude, bubble and spike evolutions in the nonlinear regimes, and the seeding of long-wavelength modes via mode coupling are determined and compared with the classical theory without ablation. Nonlinear stability above the linear cutoff is also predicted.