Species of the Burkholderia cepacia complex are associated with opportunistic infection in patients with cystic fibrosis. For years now, B. multivorans and B. cenocepacia have been the most ...frequently isolated species within the complex in such patients. However, between 2008 and 2012, the overall incidence of these species in Spain (17.7% and 12.5% respectively) was overtaken by that of B. contaminans (36.5%). The population structure of B. contaminans isolates from Spanish patients with cystic fibrosis was analysed using multilocus sequence typing and pulsed-field gel electrophoresis (PFGE). Three major known sequence types (ST102, ST404 and ST482) and a new one (ST771) were identified among 59 isolates. In addition, PFGE detected 17 pulsotypes. Susceptibility to antibiotics was examined using the Etest. Cotrimoxazole and ceftazidime were the most active antibiotics against B. contaminans, inhibiting growth in 88% and 86% of the isolates, respectively. In addition, this species showed less resistance to most of the antibiotics tested than did either B. multivorans or B. cenocepacia isolates recovered from similar Spanish patients.
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•Hydro-environmental changes in an anthropized river mouth (S Spain) were studied.•Surface water and groundwater dynamics have been modified after river channelization.•Land use ...change has an important influence on hydrologic regime.•Wetlands salinization has been driven by the diversion of groundwater flows.•Bird species abundance and diversity vary depending on the water quality.
The Guadalhorce River mouth (Málaga, Southern Spain) was channelized between 1997 and 2003 to reduce flooding potential in adjacent densely populated sections of Málaga. The channel was bifurcated near the Mediterranean Sea, surrounding an isolated wetland complex composed of eight different ponds. Groundwater-level and wetland-stage data, combined with water-chemistry data from wells and wetlands, collected since 1977, have documented the hydrological and ecological responses to channelization. The results show that channelization has extended the tidal influence inland from the Mediterranean Sea through the Guadalhorce River and the subjacent coastal aquifers, producing a change in groundwater hydrodynamics. The isolation of the wetlands resulting from channelization has provoked a significant salinization of both surface water and groundwater, the extent of which varies among wetlands. These decadal-scale changes in water chemistry have promoted the appearance or increase of halophilic vegetation and have caused a shift from diving birds to predominantly shorebirds in some wetlands. Documentation of these unexpected ecosystem responses is a necessary first step for land managers who need to consider groundwater and surface water as a single resource, particularly in groundwater-dependent ecosystems along the densely populated and ecologically sensitive Mediterranean coastal areas.
Background
The recommended treatment in patients with severe haemophilia is prophylaxis. This prevents bleedings and reduces or delays the haemophilic arthropathy. Adherence defined as the follow‐up ...of the patient to the prescriptions of the health professional to his treatment, both pharmacological and modifications in habits or stylelifes. Adherence rates in haemophilia are better than in other chronic diseases, but there remain reasons for nonadherence. The aim was to see if disease behaviour and disease perception together with coping strategies modulate adherence to treatment.
Material and Methods
Multicenter cross‐sectional descriptive study. Patients recruited in Units of Hemophilia Hospitals and Regional Haemophilia Associations. Twenty‐three patients participated The instruments used are as follows: data sheet, SF‐36, A36 Hemophilia‐Qol, Illness Perception Questionnaire‐Revised (IPQ‐R), Illness Behavior Questionnaire (IBQ) and Coping Strategies Inventory (CSI) and VERITAS‐Pro.
Results
We found that 56% of patients with haemophilia are adherent. The most relevant clinical variables were hemarthrosis, diagnosis of arthropathy and presence of any coinfection, as well as family history, labour status and sociodemographic variables. Age was not a relevant variable in adherence. The worst adherence coincides with poorer quality of life and inadequate coping style. Nonadherent patients show greater conviction of disease, perception of cyclicity, more hypochondriacal behaviour towards the illness and perception concern about possible side effects of medication.
Conclusion
Adherence in haemophilia requires a more experiential approach and individualized education. It is important that professionals take into account the patient's perception, behaviour and attitude towards the disease to achieve a better adaptation of their coping resources.
We herein present an analysis of the sources of atmospheric moisture for Central America using a Lagrangian technique. The results of backward and forward moisture tracking analysis using the ...FLEXPART model has enabled the identification of the main sources of moisture that reach Central America, as well as an evaluation of their spatial evolution during their passage toward the region of interest. Data from the European Center for Medium‐Range Weather Forecasts (ECMWF) for a 5 year period (2000–2004) were used as input for the FLEXPART model. The applied method reproduces the variations in the location of the Intertropical Convergence Zone (ITCZ) over the study area very well. The primary source of moisture for Central America is identified over the Caribbean Sea, and a secondary source appears to exist near the equatorial Pacific region. The dominance of the Caribbean Sea region as a source of moisture for this region is clear, as is the importance of the Caribbean Low‐Level Jet (CLLJ) as the principal transport mechanism. These characteristics are confirmed by inspection of the moisture transport patterns and their seasonal behavior.
This paper presents a new experimental setup to study dynamic fragmentation of metallic rings manufactured by 3D-printing technology. The ring is inserted over a ductile thin-walled tube which is ...impacted axially by a conical-nosed cylindrical projectile fired by a single-stage light–gas gun. The diameter of the projectile is larger than the internal diameter of the thin-walled tube, which expands as the projectile advances, pushing radially outwards the metallic ring, that eventually breaks into multiple fragments. The impact velocities considered in the present experimental campaign range from 197 m/s to 385 m/s. The AlSi10Mg ring specimens are printed by Selective Laser Melting technique, with an inner diameter of 14 mm and square cross section of 2 × 2 mm2. To obtain time-resolved information on the mechanics of fragmentation, the number of fractures, and the size of the fragments, the tests have been recorded with two-high speed cameras. A tunnel-shaped soft casing made of polymer foam is placed around the specimen to softly recover the ejected fragments, that have been weighted and sized to determine the statistics of the fragments size distribution. In addition, the predictions of the fragmentation theory of Kipp and Grady (1985) for the evolution of the number of fragments with the impact velocity have been compared with the experimental evidence, and an excellent quantitative agreement has been found within the whole range of loading rates investigated. Compared to other available techniques for dynamic fragmentation of rings, in which the expansion of the specimen is driven by electromagnetic or explosive loading, this experimental setup stands out for its simplicity, fast operation, quick assembly, and flexibility to test different engineering materials, which facilitates performing extensive experimental campaigns (34 successful tests have been carried out in this research). To the authors’ knowledge, this paper presents the most comprehensive data set to date on the fragmentation of dynamically expanded printed rings, including the first high-resolution video recordings of the formation of multiple cracks throughout the circumference of the samples, and scanning electron microscopy images of the fractures showing the porous microstructure on the cracks surface.
•Novel high-velocity impact test to study dynamic fragmentation of rings.•Expansion of 3D-printed AlSi10Mg rings up to 15000 s−1.•Activation of fracture sites by large pores and printing defects.•Narrower size distributions with increasing impact velocity.•The setup stands out for its simplicity and fast operation.
•GaAs films were deposited on quartz by CSVT technique, using GaAs wafers.•GaN samples on quartz were obtained by nitridation of the GaAs films.•The nitridation of the samples obtained by CSVT is a ...low-cost method to obtain GaN.•The preferential structure of the nitridated samples (GaN samples) is the hexagonal structure.
The use of gallium arsenide (GaAs) films to obtain gallium nitride (GaN) on a quartz substrate is reported herein. The GaAs films were deposited on quartz substrates via the close-spaced vapor transport technique (CSVT) with good crystalline quality. GaN was obtained via nitridation wherein the GaAs samples were subjected to ammonia and hydrogen flow at atmospheric pressure. Several experiments were conducted at 800 °C, 900 °C, and 1000 °C, suggesting that nitridation at 900 °C is suitable for GaN obtention. Another group of experiments was conducted to observe the effect of nitridation time on the morphology of GaN. The nitridation temperature was kept at 900 °C while the nitridation times were 10, 20, and 30 min. XRD and EDS characterizations revealed that the nitridation time determines the production of samples with both GaAs and GaN structures (10 min) or only the GaN structure (20 and 30 min). A GaN film exhibiting a wurtzite preferential structure was obtained subsequent to 30 min of nitridation.
This paper presents an adaptive optimal control strategy focused on improving ride comfort by minimising the root mean square of accelerations measured at seven locations on the carbody floor. It ...requires preview knowledge of both the train speed and the standard track quality (not the deterministic track disturbances) and differs from other works in considering pointwise constraints (upper and lower secondary suspension travel limits). Adaptive control is achieved by varying the diameter of the restriction orifice which connects the pneumatic spring to the auxiliary air reservoir, which confers different dynamic stiffness and damping to the front and rear secondary suspensions. Decision maps with the front and rear optimal diameters for five track irregularity levels and six different speeds were obtained using a Monte Carlo strategy based on solving the optimal control problem for 240 stochastic realisations of time-varying track irregularities of 300 s. Results show that the adaptive optimal control provides a successful compromise between comfort and safety which overshadows the conventional passive approach: it improves comfort up to 50% with respect to stiff passive configurations and it guarantees constraint fulfilment unlike compliant passive configurations.
Commercially pure titanium (c.p. Ti) is one of the best metallic biomaterials for bone tissue replacement. However, one of its main drawbacks, which compromises the service reliability of the ...implants, is the stress-shielding phenomenon (Young’s modulus mismatch with respect to that one of the bone). Several previous works attempted to solve this problem. One alternative to solve that problem has been the development of biocomposites implants and, more recently, the fabrication of titanium porous implants. In this work, porous samples of c.p. Ti grade 4 were obtained using conventional powder metallurgy technique. The influence of the processing parameters (compacting pressure and sintering temperature) on the microstructure features (size, type, morphology, and percentage of porosity), as well as on the mechanical properties (compressive yield strength, and conventional and dynamic Young’s modulus) were investigated. The results indicated that there is an increment in density, roundness of pores, and mean free path between them as compacting pressure and/or sintering temperature is increased. The Young’s modulus (conventional and dynamic) and yield strength showed the same behavior. Better stiffness results, in the central part of cylindrical samples, were obtained for a uniaxial compression of 38.5 MPa using a sintering temperature of 1273 K and 1373 K (1000 °C and 1100 °C). An evaluation of porosity and Young’s modulus along a cylindrical sample divided in three parts showed that is possible to obtain a titanium sample with graded porosity that could be used to design implants. This approach opens a new alternative to solve the bone resorption problems associated with the stress-shielding phenomenon.
Burkholderia
spp. strains collected in Spain over a 13-year period from patients with cystic fibrosis (CF) (
n
= 148), non-CF patients (
n
= 103) and from environmental sources (
n
= 64) were ...characterised. One hundred and forty-one of the examined strains were involved in seven suspected nosocomial disease outbreaks. Strains were identified by their 16s rRNA and
rec
A genes. Their genetic relatedness, the possession of cable pili and the
B. cepacia
epidemic strain marker (BCESM), and their susceptibility to antimicrobial agents were studied using pulsed-field gel electrophoresis (PFGE),
cbl
A and
esm
R genes analysis, and by the E-test, respectively. The genomovar distribution for the 315 strains was as follows:
B. stabilis
29.5 %,
B. cepacia
14.9 %,
B. multivorans
11.1 %,
B. cenocepacia
IIIA 9.5 %,
B. vietnamiensis
3.8 %,
B. cenocepacia
IIIB 3.5 %, and
B. ambifaria
and
B. pyrrocinia
0.3 % each. The genetic diversity of the
B. cepacia
complex (Bcc) was ample, with 57 different
Spe
I types, showing a genetic similarity of 36.4–96.6 %. No strain carried
cbl
A, whereas 25
B. cenocepacia
genotypes harboured BCESM (23 from patients with CF). Antimicrobial resistance rates to tobramycin (TOB; 86 %) and imipenem (IPM; 67 %) were high. The strains from patients with CF showed significantly greater resistance to piperacillin (PIP), levofloxacin (LVX) and co-trimoxazole (SXT) than those isolated from non-CF patients (
p
< 0.05). In conclusion,
B. cenocepacia
was the most prevalent genomovar found in patients with CF (19.1 %), whereas
B. cepacia
was the most common among non-CF patients (20.7 %).
B. stabilis
(47.6 %) was the most common environmental genomovar. Susceptibility to antimicrobial agents depended on genomovar status and strain origin.
The proton drip-line nucleus 17Ne is considered a good candidate for a Borromean two-proton halo with a 15O + p + p structure. Angular distributions of the elastic scattering and inclusive 15O ...production for a 136 MeV 17Ne beam incident on a 208Pb target were measured for the first time at the SPIRAL1 facility, GANIL. Use of the GLORIA detector array allowed high-resolution data over a wide angular range from 20∘ up to 95∘ in the laboratory frame to be obtained. The elastic scattering angular distribution shows similarities with those for both 6He and 20Ne at equivalent collision energies with respect to the corresponding Coulomb barriers, exhibiting the suppression of the Coulomb rainbow peak characteristic of strong coupling. Optical model and coupled channel fits suggest that this is due to a combination of coupling to low-lying quadrupole resonances and Coulomb dipole coupling to the low-lying continuum, although their relative importance depends on the relevant B(E2) values which remain to be firmly determined.
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