•Prescribed fire caused considerable C losses at the 0–1 cm depth, mostly from POM.•Uneven combustion resulted in few qualitative changes in the remaining organic matter.•Bioavailable N showed ...transient increases, while S and P gradually declined after fire.•Steadier nutrient inputs were derived from the breakdown of particulate charcoal.
High-mountain soils are rich in partially decomposed organic matter, which is highly sensitive to mineralization and fire. Prescribed burning is performed in the Pyrenees to keep subalpine grasslands open for grazing. The compositions of the ash, litter and duff layers, and the particulate organic matter (POM) of the topsoil in the 0–1, 1–2, 2–3, and 3–5 cm depths were analyzed in relation to the nutrient availability after the prescribed burning of a stand encroached by erizón (Echinospartum horridum). The concentrations of C, N, P, and S and organic components (nonstructural, hemicellulose, cellulose, and lignin-type) were determined before the prescribed burn and 0, 6, 12, 18, and 24 months after the prescribed burn. The fire consumed the aboveground biomass, the litter and part of the duff layer, and the most thermostable (i.e., lignin-type) components and the least volatile elements (P, S) were selectively preserved in the resulting ash. Prescribed burning caused significant losses of organic-C and N only in the 0–1 cm depth (–72% and –68%, respectively). The organic-C loss was mostly (82%) from the POM, whereas the N loss was from more similar proportions of the POM (57%) and the nonparticulate organic matter (NPOM) (43%). However, few changes were observed in the composition of the organic matter, which pointed to a largely uneven combustion that resulted in a substantial part of the organic matter remaining largely untouched by the fire. After 6 months, the duff layer was depleted in hemicellulose by 32% compared to immediately after the burn, and fragmentation of the POM into the NPOM was observed. During the second spring, N- and P-rich charred POM were incorporated into the top 1 cm, while C-rich charcoal particles underwent fragmentation and vertical transport into the deeper soil. The preburn ecosytem was limited by P, and likely also by S. The plant available N showed transient increases of 1.5–2.1 times the immediate postburn levels for nitrate-N at 12 months after burning, and of up to 10–20 times for ammonium-N at 18 months. In contrast, the concentrations of plant-available P and S gradually declined to 1.8–3.3 and 1.8–4.0 times, respectively, lower at 24 months after the burn. Results indicated that fire-induced increases in the nutrient availability can be short-lived in high-mountain habitats, but steadier and likely more persistent nutrient inputs can derive from the gradual breakdown of charred organic matter.
We investigated whether human-induced soil degradation may hinder the regeneration of a semiarid Mediterranean-type ecosystem with high biodiversity and conservation interest on the Canary Islands. ...To further this aim, the replacement of plant species and life-forms and the variation in soil quality were studied during the process of succession in old fields abandoned at different times and in relicts of the original thermophilous woodland by means of multivariate techniques of ordination (RDA, DCA, CCA) and clustering (k-means + IndVal). The studied ecosystem showed a limited capacity for recovery, which appears to be lower than in other similar semiarid Mediterranean ecosystems. Soil parent material exerted a considerable influence on plant reestablishment, and this process was more efficient with pumice-type rocks. Human activities have given rise to a loss of soil organic matter and an enrichment of certain nutrients, which revert to their normal levels once disturbance ceases. However, the erosion resulting from ploughing, farming and subsequent land abandonment has resulted in irreversible degradation of the soil water regime, thus severely limiting the restoration of the original ecosystem. We concluded that aridification due to soil degradation may, in certain cases, prevent the complete regeneration of thermophilous woodlands of the Canary Islands, and it must be taken into account when performing restoration activities. Pumice mulch can be useful for restoration, as it provides a suitable substrate in key stages of the plant recolonisation process.
► We studied the natural regeneration of threatened woodland in the Canary Islands. ► Succession coincided with variation in soil properties related to water availability. ► Soil processes and plant recolonization vary depending on the soil parent material. ► Not-reversed soil degradation may hinder the restoration of the ecosystem. ► Lower resilience was observed in relation to other semiarid Mediterranean ecosystems.
The presence of Cryptosporidium and Giardia in 221 fecal samples from different species of Antarctic pinnipeds was investigated by immunofluorescence microscopy and PCR. Cryptosporidium, a skunk-like ...genotype, was detected only in a southern elephant seal. Giardia was not detected. This is the first report of a Cryptosporidium sp. in Antarctic marine mammals.
Although Andosols are relatively resistant to water erosion, they can be severely affected by changes in land use, resulting in accelerated erosion and loss of soil organic matter (SOM). We ...hypothesized that if the contents of specific components of SOM and organo–metallic complexes (humic acids –HAs–, fulvic acids –FAs–, sodium pyrophosphate extractable carbon –Cp–, aluminium –Alp–, and iron –Fep–) consistently tend towards certain ratios in A and B horizons, they could be used to identify soils denuded by erosion. To test this hypothesis, we investigated the vertical distribution of humus components and certain ratios, namely C‐HA/C‐FA, C‐FA/total organic C (TOC), Cp/TOC and (Fep + Alp)/C‐FA, in representative profiles of andic soils located in natural ecosystems with different degrees of human disturbance. Furthermore, we analysed these parameters in the topsoil of a natural protected area and in adjacent soils under different land use scenarios (natural reserve vs. traditional exploitation). We found that the ratios of C‐HA/C‐FA and, to a lesser extent, of C‐FA/TOC and Cp/TOC changed with depth in the selected soil profiles, but the values were characteristic of each type of soil horizon. The values of these ratios in the topsoils of the disturbed areas were closer to a B horizon than an A horizon. This pattern may be superimposed on pre‐existing gradients, such as those related to the type of natural vegetation. The use of these indices emerges as a possible land use and erosion indicator.
The presence of Campylobacter spp. was investigated in 41 Antarctic fur seals (Arctocephalus gazella) and 9 Weddell seals (Leptonychotes weddellii) at Deception Island, Antarctica. Infections were ...encountered in six Antarctic fur seals. The isolates, the first reported from marine mammals in the Antarctic region, were identified as Campylobacter insulaenigrae and Campylobacter lari.
Background and importanceOccupational exposure to hazardous drugs (HD) can cause damage to health in exposed healthcare professionals, so protective measures must be taken.Aim and objectivesTo ...identify HD included in the pharmacotherapeutic guide (GFT) of our hospital and dangerous situations to subsequently develop a safe work procedure for workers.Material and methodsWe conducted a systematic review of publications in the past 10 years in humans in the database PubMed using as MESH terms: hazardous drugs, safe handling and occupational exposure, and combining related descriptors. Inclusion criteria were a list of medications from the GFT of our hospital. The comparator was a list established by the National Institute for Occupational Safety and Health (NIOSH), year 2014.ResultsThe main variable studied was identification of HD: 274 drugs with active ingredients classified as HD were detected in our GFT. In addition, despite not being in the NIOSH listings, acenocoumarol was considered a HD due to its similarity to warfarin (list 3 NIOSH). Therefore, 275 medications were included. Of these 275 drugs, corresponding to 151 active substances, 92 were included in list 1 (antineoplastic medicine), 26 in list 2 (non-antineoplastic drugs that meet at least one hazard criteria), 26 in list 3 (drugs that pose a risk to the reproductive process that may affect men/women who are actively trying to conceive, and pregnant women/breastfeeding period, but that do not pose a risk to the rest of the staff) and 7 according to the medication’s datasheet. The second variable studied was identification of processes that cause a risk to the safety of workers in contact with HD. Four processes were found: reception, transport and distribution, preparation and treatment of waste, which in the absence of specific preventive measures cause a risk to the safety and health of workers.Conclusion and relevanceThe identification of MP is a key aspect to avoid occupational risks and ensure the safety of the healthcare professional. Recent research identified dangerous situations and established an association between occupational contamination and levels of exposure to antineoplastic drugs, with the training and information of the health worker in MP matters being a crucial aspect.References and/or acknowledgementsNo conflict of interest.
NEXT is an experiment dedicated to neutrinoless double beta decay searches in xenon. The detector is a TPC, holding 100 kg of high-pressure xenon enriched in the 136Xe isotope. It is under ...construction in the Laboratorio Subterráneo de Canfranc in Spain, and it will begin operations in 2015. The NEXT detector concept provides an energy resolutionbetter than 1% FWHM and a topological signal that can be used to reduce the background. Furthermore, the NEXT technology can be extrapolated to a 1 ton-scale experiment.
Background and importanceThe incidence and severity of cases of Clostridium difficile infection (CDI) has been increasing, as well as hospital stays and hospitalisation costs.Aim and objectivesTo ...analyse the therapeutic approach of CDI and the contribution of risk factors.Material and methodsA retrospective observational study was conducted in patients with culture and/or positive toxins for CD during 2018. The information was obtained after review of the clinical histories of patients with CDI: demographic data, previous antibiotic treatment, risk factors (age, SNG, treatment with immunosuppressants, PPIs, laxatives, NSAIDs or IBD), severity of the episode, treatment established, subsequent recurrences (<4 months after treatment) and complications.ResultsThirty patients were included, 75.86% with a positive toxin. Average age was 64.12 years, 65.52% of patients were women and 96.55% had received previous antibiotic treatments (broad spectrum penicillins, cephalosporins and quinolones). Risk factors: 58.62% (17) >65 years, 82.76% (24) undergoing treatment with PPIs, 20.68% (6) NSAIDs,13.79% (4) laxatives, 31.03% (9) immunosuppressants,13.79% (4) had IBD and 10.34% (3) SNG.CDI were considered mild–moderate in 93.1% (28) of patients and severe in 6.9% (2). They were treated with vancomycin (68.97%), metronidazole (6.9%) and vancomycin/metronidazole (17.24%), and 2 were untreated. Most common pattern was vancomycin 250 mg/6 hours for an average of 14 days. One patient presented with toxicoderma after vancomycin and 10.3% (3) presented recurrences (0.5–3.5 months): 2 patients were treated with vancomycin/metronidazole, and after a new recurrence with vancomycin/fidaxomycin. In the other patient, bezlotuxumab/vancomycin was used first with a good resolution.In 79.31% (23) of patients their infectious condition was resolved satisfactorily. Three patients presented complications (two sepsis and one pseudomembranous colitis). The rest of the follow-up losses were due to transfer (3) and success for other reasons (1).Conclusion and relevanceThe majority of patients presented with mild–moderate CDI and vancomycin was used as usual therapy with good resolution. Risk factors included prior use of antibiotics, immunosuppressants and PPIs. It is essential to stratify patients according to severity and re-treat according to the previous episode.References and/or acknowledgementsNo conflict of interest.
This paper studies fire severity through changes in the composition of the 1:5 soil: water extract in burnt and unburnt samples collected after a wildfire that affected 7.1 ha of mountainous broom ...scrub (Teide broom,
Spartocytisus supranubius L.) in Tenerife (Canary Islands). Soil samples were collected over a regular sampling grid and analysed for pH, electrical conductivity (E.C.), and soluble cations (Ca
+2, Mg
+2, K
+, and NH
4
+–N) and anions (P, SO
4
−
2
–S, and NO
3
−‑N). A visual estimation of fire effects on individual broom plants was also conducted. The results show significant differences between burnt and unburnt samples for pH, E.C. and soluble ions (except for P), which generally agrees with data reported in the literature. Although fire severity, as estimated from the degree of fuel combustion, correlated significantly with most of the studied parameters, the qualitative fire severity indexes failed to discriminate sample groups apparently exposed to moderate fire severity conditions. Multivariate statistical analysis (PCA) allowed extracting two main factors, capable to account for 88% of total variability, after rejecting three variables (inorganic N-forms and K
+). These factors were related to fire severity and pH-dependent Ca
+2 and P reactions, respectively.
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