Current ambient ozone levels mitigate the effect of Puccinia striiformis on wheat: Is Mediterranean wheat ready for pre-industrial background ozone levels?

Increasing surface ozone is a main concern for crop production in the Global Change framework, especially in the Mediterranean basin where climate conditions favor its photochemical formation. Meanwhile, increasing common crop diseases, such as yellow rust, one of the most important pathogens affecting global wheat production has been detected in the area in recent decades. However, the impact of O3 on the occurrence and impact of fungal diseases is scarcely understood. A close-to-field-conditions assay (Open Top Chamber facility) situated in a Mediterranean cereal rainfed farming area was carried out to study the impact of increasing O3 levels and N-fertilization on spontaneous fungal outbreaks in wheat. Four O3-fumigation levels reproducing pre-industrial to future pollutant atmospheres with additional 20 and 40 nL L-1 over the ambient levels were considered (7 h-mean ranging from 28 to 86 nL L-1). Two top N-fertilization supplementations (100 and 200 kg ha-1) were nested within the O3 treatments; foliar damage, pigment content and gas exchange parameters were measured. Pre-industrial natural background O3 levels strongly favored the yellow rust infection, where the O3-polluted levels currently observed at the farm highly benefited the crop, mitigating the presence of rust by 22 %. However, future expected high O3-levels neutralized the beneficial infection-controlling effect by inducing early wheat senescence, decreasing the chlorophyll index of the older leaves by up to 43 % under the higher O3 exposure. Nitrogen promoted the rust infection by up to 49.5 % without interacting with the O3-factor. Achieving future air quality standards might require considering new varietal improvement programs, to be able to adapt crops to an increased pathogen tolerance without requiring the assistance provided by O3-pollution.

A Bayesian network model for predicting cardiovascular risk.

BACKGROUND AND OBJECTIVE: Cardiovascular diseases are the leading death cause in Europe and entail large treatment costs. Cardiovascular risk prediction is crucial for the management and control of cardiovascular diseases. Based on a Bayesian network built from a large population database and expert judgment, this work studies interrelations between cardiovascular risk factors, emphasizing the predictive assessment of medical conditions, and providing a computational tool to explore and hypothesize such interrelations. METHODS: We implement a Bayesian network model that considers modifiable and non-modifiable cardiovascular risk factors as well as related medical conditions. Both the structure and the probability tables in the underlying model are built using a large dataset collected from annual work health assessments as well as expert information, with uncertainty characterized through posterior distributions. RESULTS: The implemented model allows for making inferences and predictions about cardiovascular risk factors. The model can be utilized as a decision- support tool to suggest diagnosis, treatment, policy, and research hypothesis. The work is complemented with a free software implementing the model for practitioners' use. CONCLUSIONS: Our implementation of the Bayesian network model facilitates answering public health, policy, diagnosis, and research questions concerning cardiovascular risk factors.

Temperature-dependent infrared ellipsometry of Mo-doped VO2 thin films across the insulator to metal transition.

We present a spectroscopic ellipsometry study of Mo-doped VO2 thin films deposited on silicon substrates for the mid-infrared range. The dielectric functions and conductivity were extracted from analytical fittings of Ψ and Δ ellipsometric angles showing a strong dependence on the dopant concentration and the temperature. Insulator-to-metal transition (IMT) temperature is found to decrease linearly with increasing doping level. A correction to the classical Drude model (termed Drude-Smith) has been shown to provide excellent fits to the experimental measurements of dielectric constants of doped/undoped films and the extracted parameters offer an adequate explanation for the IMT based on the carriers backscattering across the percolation transition. The smoother IMT observed in the hysteresis loops as the doping concentration is increased, is explained by charge density accumulation, which we quantify through the integral of optical conductivity. In addition, we describe the physics behind a localized Fano resonance that has not yet been demonstrated and explained in the literature for doped/undoped VO2 films.

The efficacy of a medication review programme conducted in an emergency department.

Background Older age and inappropriate prescribing is related to a greater rate of emergency department visits and hospitalisations. Objective To assess the efficacy of an interprofessional collaboration programme in which a review of the medication of older patients seen in the emergency observation unit was carried out. Setting Emergency departments at four Spanish hospitals. Method Randomised, controlled study. Patients over 65 years of age presenting to the emergency department were randomised to a control or an intervention group. In the intervention group, a pharmacist reviewed the patients' chronic medication and identified any potentially inappropriate prescriptions based on the STOPP/START criteria. Each case was discussed with the emergency specialist and a recommendation to modify the treatment was sent to the general practitioner. Main outcome measure Rate of emergency visits and hospital admissions. Results The adjusted rate ratio of emergency visits and hospital admissions was 0.808 (95% CI 0.617 to 1.059) at 3 months, 0.888 (95% CI 0.696 to 1.134) at 6 months and 0.954 (95% CI 0.772 to 1.179) at 12 months. There was a statistically significant reduction at 3 months in two of the hospitals that participated in the study [adjusted rate ratio at 3 months was 0.452 (95% CI 0.222 to 0.923) in hospital 3 and 0.567 (95% CI 0.328 to 0.983) in hospital 4]. Conclusion Overall, the intervention did not reduce the number of emergency visits and hospital admissions. However, a significant effect was observed in centres were a high acceptance rate of treatment recommendations was achieved.

Note: A simple multi-channel optical system for modulation spectroscopies.

Photoreflectance-difference (PR/PRD) and reflectance-difference (RD) spectroscopies employ synchronic detection usually with lock-in amplifiers operating at moderate (200-1000 Hz) and high (50-100 KHz) modulation frequencies, respectively. Here, we report a measurement system for these spectroscopies based on a multichannel CCD spectrometer without a lock-in amplifier. In the proposed scheme, a typical PRD or RD spectrum consists of numerical subtractions between a thousand CCD captures recorded, while a photoelastic modulator is either operating or inhibited. This is advantageous and fits the slow response of CCD detectors to high modulation frequencies. The resulting spectra are processed with Savitzky-Golay filtering and compared well with those measured with conventional scanning systems based on lock-in amplifiers.

Higher measured moisture in California homes with qualitative evidence of dampness.

Relationships between measured moisture and qualitative dampness indicators (mold odor, visible mold, visible water damage, or peeling paint) were evaluated using data collected from California homes in a prospective birth cohort study when the infants were 6 or 12 months of age (737 home visits). For repeated visits, agreement between observation of the presence/absence of each qualitative indicator at both visits was high (71-87%, P < 0.0001). Among individual indicators, musty odor and visible mold were most strongly correlated with elevated moisture readings. Measured moisture differed significantly between repeated visits in opposite seasons (P < 0.0001), and dampness increased with the number of indicators in a home. Linear mixed-effect models showed that 10-unit increases in maximum measured moisture were associated with the presence of 0.5 additional dampness indicators (P < 0.001). Bedroom (BR) walls were damper than living room (LR) walls in the same homes (P < 0.0001), although both average and maximum readings were positively correlated across room type (r = 0.75 and 0.67, respectively, both P < 0.0001). Exterior walls were significantly damper than interior walls (P < 0.0001 in both LRs and BRs), but no differences were observed between maximum wall readings and measurements at either window corners or sites of suspected dampness.

Genomic-enabled prediction with classification algorithms.

Pearson's correlation coefficient (ρ) is the most commonly reported metric of the success of prediction in genomic selection (GS). However, in real breeding ρ may not be very useful for assessing the quality of the regression in the tails of the distribution, where individuals are chosen for selection. This research used 14 maize and 16 wheat data sets with different trait-environment combinations. Six different models were evaluated by means of a cross-validation scheme (50 random partitions each, with 90% of the individuals in the training set and 10% in the testing set). The predictive accuracy of these algorithms for selecting individuals belonging to the best α=10, 15, 20, 25, 30, 35, 40% of the distribution was estimated using Cohen's kappa coefficient (κ) and an ad hoc measure, which we call relative efficiency (RE), which indicates the expected genetic gain due to selection when individuals are selected based on GS exclusively. We put special emphasis on the analysis for α=15%, because it is a percentile commonly used in plant breeding programmes (for example, at CIMMYT). We also used ρ as a criterion for overall success. The algorithms used were: Bayesian LASSO (BL), Ridge Regression (RR), Reproducing Kernel Hilbert Spaces (RHKS), Random Forest Regression (RFR), and Support Vector Regression (SVR) with linear (lin) and Gaussian kernels (rbf). The performance of regression methods for selecting the best individuals was compared with that of three supervised classification algorithms: Random Forest Classification (RFC) and Support Vector Classification (SVC) with linear (lin) and Gaussian (rbf) kernels. Classification methods were evaluated using the same cross-validation scheme but with the response vector of the original training sets dichotomised using a given threshold. For α=15%, SVC-lin presented the highest κ coefficients in 13 of the 14 maize data sets, with best values ranging from 0.131 to 0.722 (statistically significant in 9 data sets) and the best RE in the same 13 data sets, with values ranging from 0.393 to 0.948 (statistically significant in 12 data sets). RR produced the best mean for both κ and RE in one data set (0.148 and 0.381, respectively). Regarding the wheat data sets, SVC-lin presented the best κ in 12 of the 16 data sets, with outcomes ranging from 0.280 to 0.580 (statistically significant in 4 data sets) and the best RE in 9 data sets ranging from 0.484 to 0.821 (statistically significant in 5 data sets). SVC-rbf (0.235), RR (0.265) and RHKS (0.422) gave the best κ in one data set each, while RHKS and BL tied for the last one (0.234). Finally, BL presented the best RE in two data sets (0.738 and 0.750), RFR (0.636) and SVC-rbf (0.617) in one and RHKS in the remaining three (0.502, 0.458 and 0.586). The difference between the performance of SVC-lin and that of the rest of the models was not so pronounced at higher percentiles of the distribution. The behaviour of regression and classification algorithms varied markedly when selection was done at different thresholds, that is, κ and RE for each algorithm depended strongly on the selection percentile. Based on the results, we propose classification method as a promising alternative for GS in plant breeding.

Evaluation of predation of the mite Lasioseius penicilliger (Aracnida: Mesostigmata) on Haemonchus contortus and bacteria-feeding nematodes.

Predation by the mite Lasioseius penicilliger was studied on three nematode species, i.e. infective larval stages (L3) of Haemonchus contortus and adults of Panagrellus redivivus and Rhabditis sp. Experiments were carried out in 5.5-cm diameter Petri dishes containing 2% water-agar over a period of 5 days. Batches of up to 1500 third-stage larvae (L3) of H. contortus and 1000 adult nematodes of P. redivivus and Rhabditis sp. were exposed to five mites in separate Petri dishes. Upon contact, each mite used its pedipalp and legs to identify and hold its prey and then used its chelicerae to feed upon the prey. Predation by L. penicilliger was chance dependent but mites became aggregated around any injured/damaged prey, thereby suggesting some form of chemoperception. The rate of predation on the three species of nematodes was high but L3 of H. contortus and adult Rhabditis sp. were preferred.

Genome-enabled prediction of genetic values using radial basis function neural networks.

The availability of high density panels of molecular markers has prompted the adoption of genomic selection (GS) methods in animal and plant breeding. In GS, parametric, semi-parametric and non-parametric regressions models are used for predicting quantitative traits. This article shows how to use neural networks with radial basis functions (RBFs) for prediction with dense molecular markers. We illustrate the use of the linear Bayesian LASSO regression model and of two non-linear regression models, reproducing kernel Hilbert spaces (RKHS) regression and radial basis function neural networks (RBFNN) on simulated data and real maize lines genotyped with 55,000 markers and evaluated for several trait-environment combinations. The empirical results of this study indicated that the three models showed similar overall prediction accuracy, with a slight and consistent superiority of RKHS and RBFNN over the additive Bayesian LASSO model. Results from the simulated data indicate that RKHS and RBFNN models captured epistatic effects; however, adding non-signal (redundant) predictors (interaction between markers) can adversely affect the predictive accuracy of the non-linear regression models.

Adsorption energetics of CO on supported Pd nanoparticles as a function of particle size by single crystal microcalorimetry.

The heat of adsorption and sticking probability of CO on well-defined Pd nanoparticles were measured as a function of particle size using single crystal adsorption microcalorimetry. Pd particles of different average sizes ranging from 120 to 4900 atoms per particle (or from 1.8 to 8 nm) and Pd(111) were used that were supported on a model in situ grown Fe(3)O(4)/Pt(111) oxide film. To precisely quantify the adsorption energies, the reflectivities of the investigated model surfaces were measured as a function of the thickness of the Fe(3)O(4) oxide layer and the amount of deposited Pd. A substantial decrease of the binding energy of CO was found with decreasing particle size. Initial heat of adsorption obtained on the virtually adsorbate-free surface was observed to be reduced by about 20-40 kJ mol(-1) on the smallest 1.8 nm sized Pd particles as compared to the larger Pd clusters and the extended Pd(111) single crystal surface. This effect is discussed in terms of the size-dependent properties of the Pd nanoparticles. The CO adsorption kinetics indicates a strong enhancement of the adsorbate flux onto the metal particles due to a capture zone effect, which involves trapping of adsorbates on the support and diffusion to metal clusters. The CO adsorption rate was found to be enhanced by a factor of ∼8 for the smallest 1.8 nm sized particles and by ∼1.4 for the particles of 7-8 nm size.

Growth and optical properties of Ag clusters deposited on poly(ethylene terephthalate).

The growth and concomitant evolution of the optical properties of Ag nano-clusters deposited on biaxially extruded poly(ethylene terephthalate) films is studied by reflectance difference spectroscopy. It is demonstrated by low energy ion scattering and simulated optical spectra that the clusters form a two-dimensional layer buried beneath the surface of the substrate. The experimental spectra are described by simulations in which different configurations of the host such as anisotropy, amorphization, and dilution are considered in an effective medium approach. The contribution of the anisotropic substrate is used to explain the resulting line shapes. We also discuss the role of the rate of change of the filling fraction with Ag coverage in the evolution of the spectra and the detection of the onset of coalescence by optical means.

A rotating-compensator based reflectance difference spectrometer for fast spectroscopic measurements.

We present a new type of reflectance difference (RD) spectrometer for fast spectroscopic measurements based on a rotating-compensator (RC) design. The instrument uses a 1024 element Si photodiode linear array for simultaneous multiwavelength detection. High quality RD spectra covering a spectral range from 1.5 to 4.5 eV can be acquired within a few seconds. A detailed description of the working principle, the instrumentation, and the algorithms used for data collection and reduction is presented, followed by a discussion of errors introduced by lamp instability and optical imperfections of the compensator. Finally, to demonstrate the performance of the new RCRD spectrometer, we illustrate its application for the in situ, real-time monitoring of the initial stages of organic thin film growth of para-sexiphenyl (p-6P) on the Cu(110)-(2 x 1)O surface.

Retardation correction for photoelastic modulator-based multichannel reflectance difference spectroscopy.

The wavelength dependence of the retardation induced by a photoelastic modulator (PEM) is a central issue in multichannel modulator-based spectroscopic ellipsometry and reflectance difference spectroscopy (RDS), where the optical signal is detected simultaneously at different wavelengths. Here we present a refined analysis of the modulator crystal's retardation and its effect on the signal quality. Two retardation correction schemes that take into account the actual wavelength dependence of the stress-optic coefficient are introduced. It is demonstrated experimentally that both methods provide a better correction than the procedure currently used in multichannel RDS. We define quality factors to evaluate the actual performance of the multichannel detection system as compared with a wavelength adaptive single-channel experiment. These quality factors thus provide a useful guideline for choosing the appropriate PEM retardation or reference wavelength in a multichannel experiment.

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Measurement of the surface strain induced by reconstructed surfaces of GaAs (001) using photoreflectance and reflectance-difference spectroscopies.

We report photoreflectance-difference and reflectance-difference measurements on reconstructed GaAs (001) surfaces. From these data the linear and quadratic electro-optic coefficient spectra are determined in the important 2.8-3.4 eV spectral region. The surface strain and fields induced by the surface reconstruction are also determined. We show experimentally that between c(4x4) and (2x4) surfaces, there is an inversion of the surface electric field which we attribute to a direct piezo-electric effect related to the surface strain induced by reconstruction.

Partial paternal uniparental disomy of chromosome 6 in an infant with neonatal diabetes, macroglossia, and craniofacial abnormalities.

Neonatal diabetes, which can be transient or permanent, is defined as hyperglycemia that presents within the first month of life and requires insulin therapy. Transient neonatal diabetes mellitus has been associated with abnormalities of the paternally inherited copy of chromosome 6, including duplications of a portion of the long arm of chromosome 6 and uniparental disomy, implicating overexpression of an imprinted gene in this disorder. To date, all patients with transient neonatal diabetes mellitus and uniparental disomy have had complete paternal isodisomy. We describe a patient with neonatal diabetes, macroglossia, and craniofacial abnormalities, with partial paternal uniparental disomy of chromosome 6 involving the distal portion of 6q, from 6q24-qter. This observation demonstrates that mitotic recombination of chromosome 6 can also give rise to uniparental disomy and neonatal diabetes, a situation similar to that observed in Beckwith-Wiedemann syndrome, another imprinted disorder. This finding has clinical implications, since somatic mosaicism for uniparental disomy of chromosome 6 should also be considered in patients with transient neonatal diabetes mellitus.

[Cerebral metastasis]. / Metástasis cerebrales.

INTRODUCTION: Cancer and its metastatic complications are one of the most important types of disease due to their high morbidity and mortality (nearly 100%). In spite of the blood-brain barrier, the brain is one of the main targets. Paradoxically, the incidence of cerebral metastases (CM) has increased due to the progress of medical science. The clinical features of CM are particularly seen in otoneurophthalmology (ONO). OBJECTIVE: To review the pathophysiology, etiology, prognosis, complementary tests and clinical features of the CM, particularly the findings of most importance in ONO. MATERIAL AND METHODS: Data on MC was obtained from MEDLINE and Cancerlit for the period 1991 to 2000. The cases of CM seen in three hospitals of different communities and levels of healthcare are also reviewed. RESULTS: The CM are mainly situated in the cortical and juxtacortical zones, causing seizures which together with headache and mental and focal motor syndromes, make up the main clinical findings. Cancer of the lung and breast are the main causes of CM, whilst cancer of the prostate metastasizes more to the base of the skull and spinal coverings. Melanoma has the greatest tendency to metastasize. In spite of surgery, radiotherapy and chemotherapy the average survival with CM is three months. CONCLUSIONS: CM is a diagnosis which should be considered in patients of middle age or older. The lung is the most usual site of origin. In spite of the dreadful prognosis, the doctor plays a decisive part in both aggressive and palliative measures.

Fabry's Disease Mimicking an Undifferentiated Connective Tissue Disease.

We describe a patient with Fabry's disease who for many years was seen in other clinics and was thought to have an undifferentiated connective tissue disease or an incomplete form of CREST syndrome. He presented with polyarthralgias; multiple telangiectasia-like lesions in his oral mucosa, hands, and periumbilical area; mild dysphagia; Raynaud's phenomenon; bilateral leg lymphedema; renal insufficiency; and aseptic bone necrosis at both knees. The diagnosis of Fabry's disease was first suspected when ultrastructural studies on his kidney revealed the typical inclusions characteristic of glycosphingolipidosis. Diagnosis of Fabry's disease was later confirmed by finding similar inclusions in skin endothelial cells and demonstrating a low alpha-galactosidase A activity in plasma. Fabry's disease, although rare, must be considered in the differential diagnosis of patients considered to have "atypical undifferentiated connective tissue diseases," even in the absence of classic angiokeratomas.

[Aortic coarctation in children. Analysis of 100 cases]. / Coartación de aorta en el niño. Análisis de 100 casos.

One hundred clinical records of coarctation of aorta are presented with 78% catheterization and 31% postmortem examination. Surgical treatment was performed in 46%, 8, in the first month of life, 13 from 1 to 6 month, 5, from 6 to 12 month, 9 from 12 to 24 month and 11 older than 2 years. The surgical mortality was 13%. There was recoarctation in 7.5%. The mortality in the patients not operated on was 31%. This mortality was influenced by the severity of associated malformations. The most frequent associated cardiac malformations were left to right shunts followed by left heart pathology. The association with complex cardiopathies was frequent.