Logistic regression models for human-caused wildfire risk estimation: analysing the effect of the spatial accuracy in fire occurrence data

About 90% of the wildland fires occurred in Southern Europe are caused by human activities. In spite of these figures, the human factor hardly ever appears in the definition of operational fire risk systems due to the difficulty of characterising it. This paper describes two spatially explicit models that predict the probability of fire occurrence due to human causes for their integration into a comprehensive fire risk–mapping methodology. A logistic regression technique at 1 × 1 km grid resolution has been used to obtain these models in the region of Madrid, a highly populated area in the centre of Spain. Socio-economic data were used as predictive variables to spatially represent anthropogenic factors related to fire risk. Historical fire occurrence from 2000 to 2005 was used as the response variable. In order to analyse the effects of the spatial accuracy of the response variable on the model performance (significant variables and classification accuracy), two different models were defined. In the first model, fire ignition points (x, y coordinates) were used as response variable. This model was compared with another one (Kernel model) where the response variable was the density of ignition points and was obtained through a kernel density interpolation technique from fire ignition points randomly located within a 10 × 10 km grid, which is the standard spatial reference unit established by the Spanish Ministry of Environment, Rural and Marine Affairs to report fire location in the national official statistics. Validation of both models was accomplished using an independent set of fire ignition points (years 2006–2007). For the validation, we used the area under the curve (AUC) obtained by a receiver-operating system. The first model performs slightly better with a value of AUC of 0.70 as opposed to 0.67 for the Kernel model. Wildland–urban interface was selected by both models with high relative importance.     

Phytomedicines for Candida-associated denture stomatitis

Phytomedicines are becoming more popular all over the world. Denture stomatitis (DS) presents as an inflammatory reaction in denture-bearing patients, under maxillary prosthesis with Candida albicans being the principal etiological agent. Many different methods of treatment for DS have been observed. The effects of the main medicinal plants claimed to be useful as antifungal agents in the treatment of DS are reviewed. Herbal remedies that have shown potential promise are mentioned, although much research is still required.     

Determination of some heavy metals and selenium in Sicilian and Calabrian citrus essential oils using derivative stripping chronopotentiometry

This paper aims to bring some novelty about the concentration of some heavy metals and selenium in biological citrus essential oils (CEO) produced in Sicily and Calabria in different crop years. Derivative stripping chronopotentiometry has been used as an accurate, sensitive, and rapid technique for the determination of Cd, Cu, Mn, Ni, Pb, Zn, and Se in hydrochloric acid extracts of CEO; in the optimized electrochemical conditions, detection limits of <1 microg kg(-1) were obtained for all of the studied metals. In particular, the concentrations of metals were determined in biological bergamot essential oils produced in Calabria in 1999 and 2000 and in biological CEO produced in Sicily in 2003 and 2004. The obtained results provided evidence that Mn was the most abundant metal in all of the studied CEO followed by Zn, Ni, Cu, Pb, and Se; Cd concentrations were always lower than the limit of detection (0.6 microg kg(-1)).     

Gene flow in common bean (Phaseolus vulgaris L.)

This study was conducted in Brazil in order to assess the potential risk posed by gene escape from transgenic into non-transgenic plants and wild populations. A new methodology was applied to evaluate the gene flow between common bean cultivars, by means of a specially delineated experiment in two stages. The first stage consisted of the planting of one cultivar with violet flowers (BB) as pollen source (‘Diamante Negro’), and a receiver (‘Talismã’) with white flowers (bb), at different distances. The source was sown in the center of the area. The pollen receiver cultivar was sown, in concentrical squares around it. At maturity, the rows were sampled at varied distances from the source in the four cardinal directions. In the second stage, the sampled seeds of the previous stage were sown, and the percentage of outcrossing was evaluated during flowering through the presence of violet flowers (Bb). The highest frequency of natural hybrids, 0.136%, occurred at a distance of 0.5 m between the cultivars. The natural outcrossing rate was practically zero beyond a distance of 3.25 m.     

Derivative potentiometric stripping analysis (dPSA) used for the determination of cadmium,copper, lead,and zinc in Sicilian olive oils

Derivative potentiometric stripping analysis (dPSA) was utilized to evaluate the Cd(II), Cu(II), Pb(II), and Zn(II) content in olive oil samples produced in Sicily in the crop year 2000-2001. The repeatability of the method was attested at 86.36% for cadmium, at 94.94% for copper, at 99.00% for lead, and at 98.92% for zinc. Recovery tests were carried out, both on cleanup procedures and on extraction steps, on olive oil spiked at different levels; obtained recoveries were 84.52 +/- 9.86 for cadmium, 97.34 +/- 2.72 for copper, 100.68 +/- 0.67 for lead and 83.35 +/- 1.72 for zinc. Theoretic detection limits were 1.2 ng g(-1) for Cd, 3.6 ng g(-1) for Cu, 5.9 ng g(-1) for Pb, and 14.3 ng g(-1) for Zn. Found concentrations range were 15.94-58.51 ng g(-1) for Cu, 32.64-156.48 ng g(-1) for Pb, and 157.00-385.22 ng g(-1) for Zn. Copper, lead, and zinc were found in all samples. The main advantage of this determination consists of a not too aggressive metals extraction procedure using hydrochloric acid, which avoids losses of elements typical of sample calcinations methods.     

Filamentous Intranuclear Inclusion Bodies in Psittacine Birds. A Structural and Ultrastructural Study

This paper concerns a disease affecting a group of African grey parrots, which involves intranuclear inclusion bodies composed of filamentous material. The disease was characterized by either sudden death or death within 2–3 days from onset of non-specific symptoms. At necropsy, gross lesions included enlarged liver, mild hepatic congestion and focal necrosis. Samples from five birds were fixed in 10% formol and routinely processed for light and electron microscopy. In four birds, numerous hepatocytes displayed an enlarged nucleus, with peripheral margination of chromatin; the nucleus was partially or wholly filled by a basophilic inclusion body. In the remaining bird, inclusion bodies were acidophilic and completely filled the nucleus; nuclear enlargement was less evident than in the other birds. At ultrastructural examination, and in both types of IIB, nuclei contained looped filaments but no evidence of viral structures. However, virion-like structures were observed in the cytoplasm of some hepatocytes.     

Simultaneous determination of Cd(II), Cu(II), Pb(II), and Zn(II) in citrus essential oils by derivative potentiometric stripping analysis

Citrus essential oils are widely used in the food, cosmetics, and pharmaceutical industries, so the determination of heavy metals content is of great importance to guarantee their quality. The present work deals with the quantification of Cd(II), Cu(II), Pb(II), and Zn(II) in different varieties of citrus essential oils, using derivative potentiometric stripping analysis. Two different metals extraction procedures, involving concentrated hydrochloric acid treatment and acid-alcoholic dissolution, are tested on lemon, mandarin, sweet orange, and bergamot essential oils, and they give very similar results. Cd(II), Cu(II), Pb(II), and Zn(II) recovery tests spanned from 95 to 100.50%, providing evidence that metals quantification remained unaffected by the cleanup steps of the two procedures. The repeatability of the hydrochloric acid extraction method, applied on different varieties of essential oils, is >95.00% for Cd(II), Cu(II), Pb(II), and Zn(II), whereas the repeatability of the acid-alcoholic dissolution method is >93.00% for Cu and Cd only in lemon oil. Detection limits obtained for the four analytes, using both procedures, ranged from 0.10 to 0.98 ng g(-)(1) in lemon, mandarin, sweet orange, and bergamot essential oils.     

Food consumption patterns in an adult urban population in Beirut, Lebanon

OBJECTIVES: To investigate, measure and assess the food consumption pattern of the adult population living in Beirut, Lebanon, and to identify inadequate or excessive intake of food groups particularly linked to non-communicable diseases. DESIGN: A cross-sectional food consumption survey was conducted in 2001. Dietary habits were assessed by means of a quantitative food-frequency questionnaire. SETTING: Dietary survey of the urban population (Beirut). SUBJECTS: Random sample of 444 adult subjects (aged 25-54 years) in Beirut. RESULTS: The mean consumption of food by the study population was estimated to be 3,030 g day(-1), providing an energy intake of 2,523.57 kcal day(-1). Fat contributed 38.9% to the average daily energy intake, protein 13.4% and carbohydrates 47.2%. Mean consumption of fruits and vegetables was approximately 367 g day(-1) and 45.3% of subjects consumed less than the recommended 400 g daily. Cereals contributed 324.5 g day(-1), providing 35.0% of daily energy intake, with bread being the most highly consumed (146.2 g day(-1)) in this food group. The mean intake of meat and poultry products was 91.7 g day(-1) and provided 8.8% of daily energy intake, with consumption of butchery products especially beef being the highest (47.6 g day(-1)) followed by poultry (36.1 g day(-1)). A low consumption of fish was noted (19.7 g day(-1)), with 73.6% of subjects consuming less than the recommended 2 servings of fish per week. Dairy products contributed 243.1 g day(-1) or 10.9% of daily energy intake, and milk was the least consumed dairy product (56.8% of consumers). The intake of added fats and oils, excluding those in cooked recipes, was 20.4 g day(-1); olive oil was not used in cooking but was added solely at the table and its mean intake was 5 g day(-1). The consumption of butter was low (0.86 g day(-1)) and vegetable oil was the type of fat mostly used in cooking. The average intake of alcoholic beverages was low (33.6 g day(-1)), accounting for 0.7% of total energy intake. Women had significantly higher intakes of milk, dairy products, vegetables and coffee than men (P < 0.05). The percentage of women who reported the use of low-fat items was significantly higher than that of men. Younger people (25-34 years) ate significantly more meat, sugar, alcoholic beverages and soft drinks, and consumed significantly less cooked vegetables and legumes, than older ones (P < 0.05). CONCLUSIONS: The rather high contribution of fat to daily energy intake, the low intake of fish and the relatively high percentage of people consuming less than the recommended amount of fruits and vegetables observed in this study suggest that the adult Lebanese population is at increased risk of cardiovascular diseases, obesity and other non-communicable diseases, which provides the basis for recommending increased intakes of fish, particularly fatty fish, and fruits and vegetables.