482 research outputs found
Mapping of some soil properties at catchment scale
[Abstract] The spatial structure of gravel content and three textural fractions (sand, silt, clay) was investigated in a 19.8 ha mixed, agricultural and forest catchment through of geostatistical techniques. Three different depths (0-15 cm, 15-30 cm and 30-45 cm) were sampled in order to describe the spatial variability from 0 to about 300 m. It was shown a spatial structure for all the studied variables, which could be described by different types of semivariograms (sphericals,exponentials an gaussians) with nugget effect component and a spatial component ranging from 3,5 to 365 m. Maps were performed using the information contained in the semivariograms by block kriging, so that contour maps were drawn for the different texture fractions and also showing the kriging errors. It was found greater spatial dependence of the studied variables in the first 15 cm than in the other depths
Follicular conjunctivitis caused by Chlamydia trachomatis in an infant Saharan population: molecular and clinical diagnosis
Aims: To ascertain the prevalence of acute trachoma as a supposed endemic disease among infants in the Saharan refugee camps of Tindouf (Algeria) and to evaluate the efficacy of treatment with a single dose of azithromycin. Methods: 527 children aged between 3 and 17 were evaluated in the camp schools in October 2001. All the children were clinically and microbiologically examined, including slit lamp checks of anterior segment and two conjunctival swabs, one for the detection of membrane lipopolysaccharide by quick immunoassay test Clearview Chlamydia MF and the other for the detection of specific DNA by chlamydia plasmid specific polymerase chain reaction (PCR) assay. After examination, a single dose of azithromycin was administered to each child. One month later samples from positive children and 12 random negative children by the first PCR were taken to perform a new PCR assay. Results: Chlamydia trachomatis was suspected in 2.47% of the children, papillary hypertrophy being the most frequently seen clinical sign. Scarring changes secondary to trachoma were detected in 11.7% of the children. Only four cases (0.8%) were positive to the immunoassay test and 12 cases (2.27%) were positive by PCR. After treatment a second PCR was performed on positive children and they were negative of chlamydia DNA amplification. However, one child who was negative and received the treatment was positive in the second PCR assay. Conclusion: Acute trachoma prevalence is much lower than expected among infants in this Saharan population. The possible reasons could be the recent improvements in hygiene and health care. Cicatricial trachoma is more frequent. The Clearview immunoassay test has very low sensitivity in the detection of this disease. A single dose of azithromycin is sufficient to treat chlamydial conjunctivitis. However, a programme of improvement in hygiene and health care is necessary to prevent re-infectio
Damage assessment and survival estimates in the wedge clam (Donax trunculus) caught by mechanical dredging in the northern Alboran Sea
This paper describes the impact of dredging on populations of the wedge clam (Donax trunculus) at two sites along the northern Alboran coast. Damage was assessed by quantifying shell and foot damage on commercial clams caught with mechanical dredges. Survival experiments were carried out to assess their survival capacity after 24 h purification treatment and 72 h cold storage, which represents an issue of great interest for fisheries research, management and marketing. Overall, 2.4% of wedge clams suffered any type of damage, including chipped edges and scratched valves. Higher proportions of shell-damaged individuals were positively correlated to bottom features (e.g. gravel content in sediment). Moreover, higher towing speed significantly increased shell damage. Analyses of shell damage areas revealed that the anterior dorsal and ventral parts of the shell are the most vulnerable to dredging. A total of 15.9% of individuals showed damage on the foot, which seems not to affect their survival. The incidence of foot damage was mostly linked to sublethal predation, reflected in a positive correlation between the proportion of foot-damaged individuals and biomass of decapod crustaceans in the fishing ground. Finally, D. trunculus exhibited very low mortality rates after 24 h purification treatment (0.2–0.4%) and 72 h cold storage (0.3–3.2%). The survival rate at the end of the experiment was high (>96%), with the highest mortality observed 96 h after the fishing day. No correlations were found between mortality rates and bottom type or towing speed.Postprin
Sleep quality in patients with heart failure in the spanish population: A cross-sectional study
Background: Heart failure is a major problem in western societies. Sleep Disorders maintain a bidirectional relationship with heart failure, as shown by studies conducted in other countries. This study aims to describe the quality of sleep in Spanish patients with heart failure.
Materials and methods: We carried out a cross-sectional study to analyze the quality of sleep in a sample of 203 patients with a diagnosis of heart failure admitted to an Internal Medicine Service. The Pittsburg Sleep Quality Index (PSQI) was used to evaluate sleep quality in our sample over a one-month period.
Results: 75% of the sample presented sleep disorders. The most common problems included the interruption of sleep (73.5% nocturia and 30% breathing difficulties); 35% had poor sleep efficiency; 33% showed a decrease in daytime performance; 84% had used hypnotics at some point to induce sleep and 35% used them regularly.
Conclusions: This is the first study to report on the perceived sleep quality of patients with heart failure in Spain. Self-perception of sleep quality differed from that estimated by the PSQI. The prevalence of the use of sleep-inducing medication was very high. The diurnal dysfunction generated by sleep disorders in a heart failure environment can contribute to the development of self-care and cognitive deterioration problems
Increased cerebrospinal fluid levels of cytokines monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-1β (MIP-1β) in patients with amyotrophic lateral sclerosis
Introduction: Neuroinflammation has recently been described in amyotrophic lateral sclerosis
(ALS). However, the precise role of such proinflammatory cytokines as monocyte chemoattractant
protein-1 (MCP-1) and macrophage inflammatory protein-1� (MIP-1�) in ALS has not yet
been determined. In this study, we determined cerebrospinal fluid (CSF) MCP-1 and MIP-1�
levels and assessed their association with the duration and severity of ALS.
Methods: Concentrations of MCP-1 and MIP-1� were determined in the CSF of 77 patients
diagnosed with ALS and 13 controls. Cytokine levels were analysed in relation to ALS duration
( 12 months) and severity ( 30 points on the ALS Functional Rating
Scale administered at hospital admission).
Results: Higher CSF MIP-1� (10.68 pg/mL vs 4.69 pg/mL, P < .0001) and MCP-1 (234.89 pg/mL
vs 160.95 pg/mL, P = .011) levels were found in the 77 patients with ALS compared to controls.
There were no differences in levels of either cytokine in relation to disease duration or severity.
However, we did observe a significant positive correlation between MIP-1� and MCP-1 in patients
with ALS.
Conclusions: The increase in MIP-1� and MCP-1 levels suggests that these cytokines may havea synergistic effect on ALS pathogenesis. However, in our cohort, no association was found witheither the duration or the clinical severity of the disease
Wavelet-based Image deconvolution for Wide Field CCD Imagery
We show how a wavelet-based image adaptive deconvolution algorithm can provide significant improvements in the analysis of wide-field CCD images. To illustrate it, we apply our deconvolution protocol to a set of images from a Baker-Nunn telescope. This f/1 instrument has an outstanding field of view of 4.4°x4.4° with high optical quality offering unique properties to study our deconvolution process and results. In particular, we obtain an estimated gain in limiting magnitude of ΔR∼0.6 mag and in limiting resolution of Δρ∼3.9 arcsec. These results increase the number of targets and the efficiency of the underlying scientific project
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