Chemical characteristics of wildfire ash across the globe and their environmental and socio-economic implications.

The mobilisation of potentially harmful chemical constituents in wildfire ash can be a major consequence of wildfires, posing widespread societal risks. Knowledge of wildfire ash chemical composition is crucial to anticipate and mitigate these risks. Here we present a comprehensive dataset on the chemical characteristics of a wide range of wildfire ashes (42 types and a total of 148 samples) from wildfires across the globe and examine their potential societal and environmental implications. An extensive review of studies analysing chemical composition in ash was also performed to complement and compare our ash dataset. Most ashes in our dataset had an alkaline reaction (mean pH 8.8, ranging between 6 and 11.2). Important constituents of wildfire ash were organic carbon (mean: 204 g kg-1), calcium, aluminium, and iron (mean: 47.9, 17.9 and 17.1 g kg-1). Mean nitrogen and phosphorus ranged between 1 and 25 g kg-1, and between 0.2 and 9.9 g kg-1, respectively. The largest concentrations of metals of concern for human and ecosystem health were observed for manganese (mean: 1488 mg kg-1; three ecosystems > 1000 mg kg-1), zinc (mean: 181 mg kg-1; two ecosystems > 500 mg kg-1) and lead (mean: 66.9 mg kg-1; two ecosystems > 200 mg kg-1). Burn severity and sampling timing were key factors influencing ash chemical characteristics like pH, carbon and nitrogen concentrations. The highest readily dissolvable fractions (as a % of ash dry weight) in water were observed for sodium (18 %) and magnesium (11.4 %). Although concentrations of elements of concern were very close to, or exceeded international contamination standards in some ashes, the actual effect of ash will depend on factors like ash loads and the dilution into environmental matrices such as water, soil and sediment. Our approach can serve as an initial methodological standardisation of wildfire ash sampling and chemical analysis protocols.

Eucalyptus Edge Effect on Quercus-Herbivore Interactions in a Neotropical Temperate Forest.

Fragmentation leads to the formation of edges between habitats, which in turn changes biotic and abiotic factors that might influence herbivory or plant-herbivory interactions. The aims of this study were to describe the herbivory community associated with oak (Quercus) and to determine the effects of proximity to a Eucalyptus edge and season on insect herbivory. We selected three forest sites that were subsequently divided into three quadrants located at different distances from the Eucalyptus edge: edge (0 m), intermediate (30 m), and oak forest interior (60 m). We randomly selected 10 oak trees per quadrant and conducted monthly surveys, during the dry and rainy season (from February to October 2010), where we quantified leaf area and the percentage of herbivory. These were analyzed using linear mixed models, with distance and season as fixed factors and individual and site as random factors. The primary oak herbivores were Lepidoptera caterpillars. We found that herbivory increased away from the edge but just during the rainy season, although higher herbivory levels were found during the dry season. These results seem to be related to a specialist community of herbivorous associated to the Quercus. This study emphasizes the importance of considering border effect, especially within Natural Protected Areas to establish strategies to improve and maintain native oak forest and the biodiversity of its Lepidoptera herbivorous community.

Enzymatic debridement: is HA-collagenase the right synergy? Randomized double-blind controlled clinical trial in venous leg ulcers.

OBJECTIVE: The aim of this study is to evaluate the efficacy and safety of a new ointment containing Hyaluronic Acid and collagenase from non-pathogenic Vibrio alginolyticus. PATIENTS AND METHODS: Double blind, multicenter, controlled clinical trial (no. ISRCTN71239043) conducted to demonstrate the superiority of Hyaluronic Acid-Collagenase applied once a day over placebo in mean reduction of devitalized/fibrinous/slough tissue after 15 days of treatment. 113 patients with venous ulcers were enrolled and randomized to receive active treatment therapy or vehicle preparation. Both arms also received compression therapy. Subjects were assessed at baseline and at 4 different clinical study visits up to a maximum of 30 days. Outcome measures included mean percentage debridement evaluated by digital planimetry, pain during change of dressing measured on a visual analogue scale and adverse event assessment for tolerance. RESULTS: After 15 days the debridement rate in the active group was 67.5% compared to 59% in the placebo group (p = 0.0436). A significantly higher number of patients in the treatment group achieved 100% debridement by day 15 (p = 0.0025) than in the control group, and a higher percentage also demonstrated complete debridement at every other time point. Pain perception was similar in both groups with low levels during medication. No differences in tolerance were observed between groups. CONCLUSIONS: Chronic venous ulcers treated with this novel compound of Hyaluronic Acid and collagenase resulted in a significantly higher debridement rate at Day 15 vs. the control group. Hyaluronic Acid-Collagenase was well tolerated and a low degree of pain was perceived during dressing change. The preparation of 0.2% of Hyaluronic acid-collagenase shows significant benefits in the management of chronic ulcers.

Microglandular hyperplasia of the uterine cervix. Cytologic diagnosis in cervical smears.

OBJECTIVE: To identify cytomorphologic features specific to microglandular hyperplasia (MGH) in cervical cytologic smears. STUDY DESIGN: Twenty-four cervical smears from 24 patients obtained before the histologic diagnosis of MGH made on colposcopically directed biopsies during a period of two years (1995-1997) were evaluated. RESULTS: Of cases with MGH, 13/24 (54%) showed the presence of bidimensional or tridimensional cellular clusters made up of cubic or cylindrical glandular cells with vacuolated cytoplasm; cells with dense cytoplasm, basaloid in appearance, corresponding to immature squamous metaplasia; and subcylindrical reserve cells with small, round nuclei and scant cytoplasm. Clusters showed microlumina or fenestrated spaces, preserved polarity and absence of nuclear peripheral dispersion. In the control group these cellular clusters were found in 6/100 (6%). Statistical analysis (chi 2) showed a strong, highly significant association (P < 0.001) of the cytologic parameters selected and the histologic diagnosis of MGH. CONCLUSION: Until now, no specific cytologic parameters were described for MGH. This study underscored the value of cytomorphologic parameters described for typical cellular clusters showing microlumina or fenestrated spaces with shared party walls and an admixture of glandular cells, and immature squamous metaplastic and subcylindrical reserve cells in the cytologic diagnosis of MGH.