2,101 research outputs found
Delineation of management zones using mobile measurements of soil apparent electrical conductivity and multivariate geostatistical techniques
Site-specific management promotes the identification and management of areas within the field, which represent subfield regions with homogeneous characteristics (management zones). However,
determination of subfield areas is difficult because of the complex combination of factors which could affect crop yield. One possibility to capture yield variability is the use of soil physical properties to define
the management zones as they are related to plant available water.
With the aim of characterizing the spatial variability of the main soil physical variables and using this information to determine potential management zones, soil samples were taken from 70 locations in a
33-ha field in Badajoz, southwestern Spain. Firstly, accurate spatial distribution maps of the soil attributes were generated by using regression kriging as the most suitable algorithm in which exhaustive secondary information on soil apparent electrical conductivity (ECa) was incorporated. ECa
measurements were carried out with a Veris 3100 operating in both shallow (0–30 cm), ECs, and deep (0–90 cm), ECd,mode. Clay, coarse sand and fine sand were the soil physical properties which exhibited
higher correlation with ECa (positively correlated with the finer texture component, clay, and negatively correlated with the coarser ones, coarse and fine sands), particularly with ECs. Thus, this was the
secondary variable used to obtain the kriged maps. Later, principal component analysis and fuzzy cluster
classification were performed to delineate management zones, resulting in two subfields to be managed separately. This number of subfields was determined using the fuzzy performance index and normalized
classification entropy as the way to optimize the classification algorithm
Use of CPAP to Reduce Arterial Stiffness in Moderate-to-Severe Obstructive Sleep Apnoea, Without Excessive Daytime Sleepiness (STIFFSLEEP): an Observational Cohort Study Protocol
INTRODUCTION: Sleepiness is a cardinal symptom in obstructive sleep apnoea (OSA) but most patients have unspecific symptoms. Arterial stiffness, evaluated by pulse wave velocity (PWV), is related to atherosclerosis and cardiovascular (CV) risk. Arterial stiffness was reported to be higher in patients with OSA, improving after treatment with continuous positive airway pressure (CPAP). This study aims to assess whether the same effect occurs in patients with OSA and without sleepiness.
METHODS AND ANALYSIS:
This observational study assesses the CV effect of CPAP therapy on a cohort of patients with moderate-to-severe OSA; the effect on the subcohorts of sleepy and non-sleepy patients will be compared. A systematic and consecutive sample of patients advised CPAP therapy will be recruited from a single outpatient sleep clinic (Centro Hospitalar de Lisboa Central-CHLC, Portugal). Eligible patients are male, younger than 65 years, with confirmed moderate-to-severe OSA and apnoea-hypopnea index (AHI) above 15/hour. Other sleep disorders, diabetes or any CV disease other than hypertension are exclusion criteria. Clinical evaluation at baseline includes Epworth Sleepiness Scale (ESS), and sleepiness is defined as ESS above 10. OSA will be confirmed by polygraphic study (cardiorespiratory, level 3). Participants are advised to undertake an assessment of carotid-femoral PWV (cf-PWV) and 24 hours evaluation of ambulatory blood pressure monitoring (ABPM), at baseline and after 4 months of CPAP therapy. Compliance and effectiveness of CPAP will be assessed. The main outcome is the variation of cf-PWV over time
Chuva de sementes sob poleiros artificiais: efeitos da subformação florestal e do uso do solo.
Estrutura populacional de Ilex paraguariensis St. Hil. (Aquifoliaceae) em fragmentos de floresta ombrófila mista.
Resumo
Soil apparent electrical conductivity and geographically weighted regression for mapping soil
To resolve the spatial variation in soil properties intensively is expensive, but
such knowledge is essential to manage the soil better and to achieve greater economic and
environmental benefits. The objective of this study was to determine whether the soil
apparent electrical conductivity (ECa), alone or combined with other variables, is a useful
alternative for providing detailed information on the soil in the Extremadura region of
Spain. Apparent soil electrical conductivity was measured and geographically weighted
regression was used to characterize the spatial variation in soil properties, which in turn
can be used for soil management. This study shows that soil cation exchange capacity,
calcium content, clay percentage and pH have a relatively strong spatial correlation with
ECa in the soil of the study area
Evaluation of spatial and temporal variability of pasture based on topography and the quality of the rainy season
Yield and botanical composition of a given dry-land pasture are heavily influenced by rainfall distribution, and vary according to topography. Through analyzing these parameters, it is possible to identify patterns of spatial distribution, related to
topographic characteristics, which can be used to improve spatial management of pasture.
The main objective of this project was to assess the role of rainfall, temperature and
topography in the spatial and temporal variability of pasture and establish models for predicting the spatial distribution and yield of certain plant species, based on its topographic characteristics. This study was carried out over three years, 2004 to 2006, in a dryland
pasture located in Southern Portugal. The data obtained were analyzed as a function of
distance to flow lines and the results demonstrate that certain topographical characteristics,
associated with agronomic information, can be very useful in explaining the spatial and
temporal variability of yield and the botanical composition of the pasture. The slope of the linear regression of the variables mentioned can be used to estimate the spatial variation of
yield and the botanical composition as a function of distance to flow lines. The regression coefficient can be estimated from the annual rainfall, given the strong correlation between the two
BioRePortAP, an electronic clinical record coupled with a database : an example of its use in a single
Aims: To evaluate the efficacy and safety of the treatment of psoriatic arthritis (PsA) patients with tumor necrosis factor (TNF) antagonists in the Rheumatology Department of Hospital de Santa Maria using the BioRePortAP.
Methods: The Portuguese Society of Rheumatology (SPR) developed an electronic medical chart coupled with a database for the follow up of PsA patients, the BioRePortAP, which was launched in May 2009. This evaluation was based on all the PsA patients that were on active treatment with TNF antagonists in September 2009 and were registered in the BioRePortAP. All the previous data on these patients were introduced in BioRePortAP using the prospective paper based follow up protocol that this Department was using since 1999. Only patients with more than 9 months of treatment were analyzed.
Results: Forty-two patients with PsA, actively treated with anti-TNF agents in September 2009, for at least 9 months, were analyzed in BioRePortAP. Twenty-three patients were male (55%) and nineteen were female (45%). The average age of these patients was 49.8±10.9 years old, the average disease duration was of 10.7±5.6 years and the mean duration of biological therapy was of 37.8±27.8 months. For the 81% of patients with peripheral joint disease there was a mean reduction of more than 80% in the swollen and tender joint counts, and almost 50% in the health assessment questionnaire (HAQ) value. In the 19% of the patients with axial involvement the reduction of BASDAI and BASFI was not statistically significative. On top of that, PASI score suffered a reduction of 64%. Fourteen patients (33.3%) had to switch their TNF antagonist treatment. 58.8% of the switches were due to adverse effects and 41.2% due to therapy failure. Regarding the 56 adverse reactions registered, only one was a severe reaction. The remaining adverse reactions were not severe and 67% of them were due to infections.
Discussion: The results of this first report of the use of the BioRePortAP in clinical practice confirm the efficacy and safety of TNF antagonist treatment in PsA. The results shown here elucidate the potential applications of BioRePortAP as a tool for efficacy and safety assessment of PsA patients treated with biotechnological drugs
Redução de compostos fenólicos de resÃduos de lagares de azeite utilizando culturas de Coriolus versicolor
In this study, C. versicolor cultures were performed during 20 days with different RLA (olive mill wastes)subtracts, 50%, 75% and 100%. During this assay, samples were collected in regular time intervals, cell growth were evaluated and broth decolorization was observed. The organic matter and total phenolic compounds level in
the culture broth showed a decrease in all RLA ratios. 50% and 75% RLA presented high total phenolic removal, 85% and 90% respectively. In the end of the assay, toxicological evaluation of the culture broth was performed against Artemia salina. These results showed a toxicological decrease of these residues after biological treatment
with C. Versicolor
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