RESUMEN
Paludiculture, the productive use of wet or rewetted peatlands, offers an option for continued land use by farmers after rewetting formerly drained peatlands, while reducing the greenhouse gas emissions from peat soils. Biodiversity conservation may benefit, but research on how biodiversity responds to paludiculture is scarce. We conducted a multi-taxon study investigating vegetation, breeding bird and arthropod diversity at six rewetted fen sites dominated by Carex or Typha species. Sites were either unharvested, low- or high-intensity managed, and were located in Mecklenburg-Vorpommern in northeastern Germany. Biodiversity was estimated across the range of Hill numbers using the iNEXT package, and species were checked for Red List status. Here we show that paludiculture sites can provide biodiversity value even while not reflecting historic fen conditions; managed sites had high plant diversity, as well as Red Listed arthropods and breeding birds. Our study demonstrates that paludiculture has the potential to provide valuable habitat for species even while productive management of the land continues.
Asunto(s)
Fitomejoramiento , Humedales , Ecosistema , Suelo , BiodiversidadRESUMEN
We systematically searched available databases. We reviewed 6,143 studies published from 1833 to 2017. Reports in English, French, German, Italian, and Spanish were considered, as were publications in other languages if definitive treatment and recurrence at specific follow-up times were described in an English abstract. We assessed data in the manner of a meta-analysis of RCTs; further we assessed non-RCTs in the manner of a merged data analysis. In the RCT analysis including 11,730 patients, Limberg & Dufourmentel operations were associated with low recurrence of 0.6% (95%CI 0.3-0.9%) 12 months and 1.8% (95%CI 1.1-2.4%) respectively 24 months postoperatively. Analysing 89,583 patients from RCTs and non-RCTs, the Karydakis & Bascom approaches were associated with recurrence of only 0.2% (95%CI 0.1-0.3%) 12 months and 0.6% (95%CI 0.5-0.8%) 24 months postoperatively. Primary midline closure exhibited long-term recurrence up to 67.9% (95%CI 53.3-82.4%) 240 months post-surgery. For most procedures, only a few RCTs without long term follow up data exist, but substitute data from numerous non-RCTs are available. Recurrence in PSD is highly dependent on surgical procedure and by follow-up time; both must be considered when drawing conclusions regarding the efficacy of a procedure.
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Seno Pilonidal/cirugía , Cuidados Posteriores , Humanos , Masculino , Seno Pilonidal/fisiopatología , Ensayos Clínicos Controlados Aleatorios como Asunto , Recurrencia , Cicatrización de HeridasRESUMEN
Elevated atmospheric input of nitrogen (N) is currently affecting plant biodiversity and ecosystem functioning. The growth and survival of numerous plant species is known to respond strongly to N fertilisation. Yet, few studies have assessed the effects of N deposition on seed quality and reproductive performance, which is an important life-history stage of plants. Here we address this knowledge gap by assessing the effects of atmospheric N deposition on seed quality of the ancient forest herb Anemone nemorosa using two complementary approaches. By taking advantage of the wide spatiotemporal variation in N deposition rates in pan-European temperate and boreal forests over 2 years, we detected positive effects of N deposition on the N concentration (percentage N per unit seed mass, increased from 2.8% to 4.1%) and N content (total N mass per seed more than doubled) of A. nemorosa seeds. In a complementary experiment, we applied ammonium nitrate to aboveground plant tissues and the soil surface to determine whether dissolved N sources in precipitation could be incorporated into seeds. Although the addition of N to leaves and the soil surface had no effect, a concentrated N solution applied to petals during anthesis resulted in increased seed mass, seed N concentration and N content. Our results demonstrate that N deposition on the petals enhances bioaccumulation of N in the seeds of A. nemorosa. Enhanced atmospheric inputs of N can thus not only affect growth and population dynamics via root or canopy uptake, but can also influence seed quality and reproduction via intake through the inflorescences.
Asunto(s)
Anemone/fisiología , Flores/metabolismo , Nitrógeno/metabolismo , Semillas/fisiología , Anemone/química , Anemone/metabolismo , Atmósfera , Clima , Europa (Continente) , Flores/química , Bosques , Nitrógeno/análisis , Reproducción/fisiologíaRESUMEN
Anthropogenic eutrophication impacts ecosystems worldwide. Here, we use a vegetation dataset from semi-natural grasslands on acidic soils sampled along a gradient in north-western Europe to examine the response of species frequency to nitrogen (N) deposition, controlling for the effects of other environmental variables. A second dataset of acidic grasslands from Germany and the Netherlands containing plots from different time periods was analysed to examine whether the results of the spatial gradient approach coincided with temporal changes in the abundance of species. Out of 44 studied species, 16 were affected by N deposition, 12 of them negatively. Soil pH and phosphorus (P) influenced 24 and 14 species, respectively, predominantly positively. Fewer species were related to the soil contents of NO3(-) or NH4(+), with no significant differences between the number of positive and negative effects. Whereas the temporal change of species was unrelated to their responses to pH, species responding negatively to N deposition, soil P and NO3(-) showed a significant decline over time in both countries. Species that were negatively affected by high N deposition and/or high soil P also showed a negative temporal trend and could be characterised by short stature and slow growth. The results confirm the negative role of N deposition for many plant species in semi-natural acidic grasslands. The negative temporal trends of species sensitive to high N deposition and soil P values clearly show a need for maintaining low soil nutrient status and for restoring the formerly infertile conditions in nutrient-enriched grasslands.
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Contaminación del Aire , Eutrofización , Pradera , Nitrógeno/análisis , Desarrollo de la Planta , Plantas , Suelo/química , Contaminantes Atmosféricos/análisis , Ecología , Contaminación Ambiental , Europa (Continente) , Alemania , Países Bajos , Fósforo/análisis , Especificidad de la EspecieRESUMEN
Climate change is acting on several aspects of plant life cycles, including the sexual reproductive stage, which is considered amongst the most sensitive life-cycle phases. In temperate forests, it is expected that climate change will lead to a compositional change in community structure due to changes in the dominance of currently more abundant forest tree species. Increasing our understanding of the effects of climate change on currently secondary tree species recruitment is therefore important to better understand and forecast population and community dynamics in forests. Here, we analyse the interactive effects of rising temperatures and soil moisture reduction on germination, seedling survival and early growth of two important secondary European tree species, Acer pseudoplatanus and A. platanoides. Additionally, we analyse the effect of the temperature experienced by the mother tree during seed production by collecting seeds of both species along a 2200-km long latitudinal gradient. For most of the responses, A. platanoides showed higher sensitivity to the treatments applied, and especially to its joint manipulation, which for some variables resulted in additive effects while for others only partial compensation. In both species, germination and survival decreased with rising temperatures and/or soil moisture reduction while early growth decreased with declining soil moisture content. We conclude that although A. platanoides germination and survival were more affected after the applied treatments, its initial higher germination and larger seedlings might allow this species to be relatively more successful than A. pseudoplatanus in the face of climate change.
Asunto(s)
Acer/fisiología , Cambio Climático , Sequías , Germinación , Regeneración , Plantones/fisiología , Semillas/fisiología , Suelo/química , Temperatura , ÁrbolesRESUMEN
There is a growing evidence base demonstrating that atmospheric nitrogen deposition presents a threat to biodiversity and ecosystem function in acid grasslands in Western Europe. Here, we report the findings of a workshop held for European policy makers to assess the perceived importance of reactive nitrogen deposition for grassland conservation, identify areas for policy development in Europe and assess the potential for managing and mitigating the impacts of nitrogen deposition. The importance of nitrogen as a pollutant is already recognized in European legislation, but there is little emphasis in policy on the evaluation of changes in biodiversity due to nitrogen. We assess the potential value of using typical species, as defined in the European Union Habitats Directive, for determining the impact of nitrogen deposition on acid grasslands. Although some species could potentially be used as indicators of nitrogen deposition, many of the typical species do not respond strongly to nitrogen deposition and are unlikely to be useful for identifying impact on an individual site. We also discuss potential mitigation measures and novel ways in which emissions from agriculture could be reduced.
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Contaminantes Atmosféricos/toxicidad , Atmósfera/química , Monitoreo del Ambiente , Nitrógeno/toxicidad , Poaceae/efectos de los fármacos , Agricultura , Contaminantes Atmosféricos/análisis , Biodiversidad , Europa (Continente) , Nitrógeno/análisis , Poaceae/crecimiento & desarrolloRESUMEN
The nutrient concentration in seeds determines many aspects of potential success of the sexual reproductive phase of plants, including the seed predation probability, efficiency of seed dispersal and seedling performance. Despite considerable research interest in latitudinal gradients of foliar nutrients, a similar gradient for seeds remains unexplored. We investigated a potential latitudinal gradient in seed nutrient concentrations within the widespread European understorey forest herb Anemone nemorosa L. We sampled seeds of A. nemorosa in 15 populations along a 1900-km long latitudinal gradient at three to seven seed collection dates post-anthesis and investigated the relative effects of growing degree-hours >5 °C, soil characteristics and latitude on seed nutrient concentrations. Seed nitrogen, nitrogen:phosphorus ratio and calcium concentration decreased towards northern latitudes, while carbon:nitrogen ratios increased. When taking differences in growing degree-hours and measured soil characteristics into account and only considering the most mature seeds, the latitudinal decline remained particularly significant for seed nitrogen concentration. We argue that the decline in seed nitrogen concentration can be attributed to northward decreasing seed provisioning due to lower soil nitrogen availability or greater investment in clonal reproduction. This pattern may have large implications for the reproductive performance of this forest herb as the degree of seed provisioning ultimately co-determines seedling survival and reproductive success.
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Anemone/química , Semillas/química , Árboles , Anemone/metabolismo , Calcio/análisis , Calcio/metabolismo , Europa (Continente) , Geografía , Nitrógeno/análisis , Nitrógeno/metabolismo , Fósforo/análisis , Fósforo/metabolismo , Semillas/metabolismo , Suelo/químicaRESUMEN
Habitat fragmentation decreases plant population size and increases population isolation, as well as altering patterns of plant-animal interactions, all of which may reduce plant fitness. Here, we studied effects of habitat fragmentation (in terms of population size and isolation) and soil quality on the reproduction of two rare legume species, Genista anglica (13 populations) and Genista pilosa (14 populations), confined to remnants of acidic and nutrient-poor Calluna heathlands. Single individuals of the Genista plants are impossible to distinguish; population size was therefore estimated according to the area occupied (referred to as population size hereafter). We collected soil samples in all heathland sites to determine content of soil water, C, N, P, Ca, K and Mg. In both species values of soil pH and C/N ratio, as well as content of soil P and base cations, reflected the highly acidic and nutrient-poor environment of the heathlands. Population sizes were unrelated to soil quality. Although the two Genista species are similar in morphology and ecology, effects of explanatory variables on reproduction were largely inconsistent across species. In G. anglica, population size had a positive impact on all reproductive variables except germination rate, which, in contrast, was the only variable affected positively by population size in G. pilosa. In both species, mean total reproductive output, calculated as the product of total seed mass per shoot and total germination, increased with increasing water content and decreased with increasing P. In G. anglica, we found positive effects of the C/N ratio on all reproductive variables except mean single and total seed mass per shoot. In summary, in both species reproductive success per shoot decreased with increasing soil nutrient availability in the heathland sites. The infestation of two large populations of G. pilosa with the pre-dispersal, seed-predating weevil Apion compactum had no significant effect on reproduction of the populations.
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Ecosistema , Genista/fisiología , Suelo/análisis , Alemania , Germinación , Modelos Lineales , Densidad de Población , Reproducción , Agua/fisiologíaRESUMEN
Sera from 19 wild caught vultures in northern Namibia and 15 (12 wild caught and three captive bred but with minimal histories) in North West Province, South Africa, were examined by an enzyme-linked immunosorbent assay (ELISA) for antibodies to the Bacillus anthracis toxin protective antigen (PA). As assessed from the baseline established with a control group of ten captive reared vultures with well-documented histories, elevated titres were found in 12 of the 19 (63%) wild caught Namibian birds as compared with none of the 15 South African ones. There was a highly significant difference between the Namibian group as a whole and the other groups (P < 0.001) and no significant difference between the South African and control groups (P > 0.05). Numbers in the Namibian group were too small to determine any significances in species-, sex- or age-related differences within the raw data showing elevated titres in four out of six Cape Vultures, Gyps coprotheres, six out of ten White-backed Vultures, Gyps africanus, and one out of three Lappet-faced Vultures, Aegypius tracheliotus, or in five of six males versus three of seven females, and ten of 15 adults versus one of four juveniles. The results are in line with the available data on the incidence of anthrax in northern Namibia and South Africa and the likely contact of the vultures tested with anthrax carcasses. It is not known whether elevated titre indicates infection per se in vultures or absorption of incompletely digested epitopes of the toxin or both. The results are discussed in relation to distances travelled by vultures as determined by new tracking techniques, how serology can reveal anthrax activity in an area and the issue of the role of vultures in transmission of anthrax.
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Carbunco/veterinaria , Anticuerpos Antibacterianos/sangre , Antígenos Bacterianos/inmunología , Bacillus anthracis/inmunología , Enfermedades de las Aves/epidemiología , Falconiformes , África Austral/epidemiología , Factores de Edad , Animales , Carbunco/epidemiología , Carbunco/transmisión , Enfermedades de las Aves/transmisión , Ensayo de Inmunoadsorción Enzimática/métodos , Ensayo de Inmunoadsorción Enzimática/veterinaria , Femenino , Cadena Alimentaria , Masculino , Estudios Seroepidemiológicos , Factores Sexuales , Especificidad de la EspecieRESUMEN
Despite the devastating collapse of three vulture populations on the Asian subcontinent as a result of their exposure to diclofenac, there is little available information on the normal physiology of many vulture species, including the African White-backed Vulture (Gyps africanus). Such information is needed to fully understand mechanisms for toxicity and to identify and prevent future health problems. The aim of this study was to establish baseline parameters for hematologic and selected serum chemistry parameters for this model species for further studies into the toxicity of diclofenac. Captive nonreleasable and wild African White-backed Vultures were used to determine reference values. For hematology, erythrocyte counts, hemoglobin concentration, hematocrit, packed cell volume, mean corpuscular volume, mean corpuscular hemoglobin concentration, and total and differential leukocyte counts were measured. Chemical analytes measured included sodium, potassium, calcium, albumin, and globulin concentrations, aspartate aminotransferase, creatine kinase, and alanine aminotransferase activities. Uric acid and urea concentrations and the urea:uric acid ratio also were evaluated. Values are presented as means, standard deviations, and reference intervals. The serum chemistry parameters selected may provide a starting point for the evaluation of changes in renal and hepatic function; these organ systems are most severely affected by diclofenac. Results were also compared with values reported for G. africanus nestlings, and from these results it is evident that the clinical pathologic parameters are age related. This indicates that the use of nestling values for the evaluation of clinical pathologic findings in adults may be unreliable and could lead to incorrect assumptions.
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Análisis Químico de la Sangre/veterinaria , Conservación de los Recursos Naturales , Falconiformes/sangre , Pruebas Hematológicas/veterinaria , Factores de Edad , Animales , Animales Recién Nacidos/sangre , Animales Salvajes , Animales de Zoológico , Diclofenaco/toxicidad , Índices de Eritrocitos/veterinaria , Falconiformes/metabolismo , Femenino , Hematócrito/veterinaria , Masculino , Valores de Referencia , Especificidad de la EspecieRESUMEN
The feasibility and safety of outpatient coronary angiography were studied in 2,106 patients. Patients were discharged with a pressure dressing 2 h after the angiographic study. No complications occurred in 99.53% of all patients. Severe complications were seen in 10 patients (0.47%). 9 patients (0.43%) had to be admitted to hospital, either for immediate treatment (4 patients) or due to complications (5 patients). Our results revealed a very low complication rate for outpatient coronary angiography. The number and severity of complications following coronary angiography did not differ significantly between inpatients and outpatients. Therefore, outpatient coronary angiography can be considered as a safe and feasible diagnostic method which may help cut health care costs.
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Atención Ambulatoria , Angiografía Coronaria/métodos , Cardiopatías/diagnóstico por imagen , Adulto , Anciano , Angiografía Coronaria/efectos adversos , Estudios de Evaluación como Asunto , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
A gel-filtration assay has been developed with which the specific interaction between Drosophila melanogaster ecdysteroid receptor and the 20-hydroxy-ecdysone responsive element of the hsp27 gene promoter region was characterized in terms of complex formation, saturation of DNA binding and the apparent molecular mass of the complex. The hsp27 DNA-binding sequence for ecdysteroid receptor in vitro was delimited by footprinting and mutational analysis. The combined results show that ecdysteroid receptor binds as a dimer to an imperfect palindromic sequence (GGTTCAATGCACT) closely resembling the structures of the different vertebrate steroid-hormone-responsive elements reported so far.
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ADN/metabolismo , Hormonas de Invertebrados/metabolismo , Receptores de Superficie Celular/metabolismo , Receptores de Esteroides/metabolismo , Animales , Secuencia de Bases , Unión Competitiva , Bovinos , Cromatografía en Gel , ADN/genética , Dermatoglifia del ADN , Drosophila melanogaster , Datos de Secuencia Molecular , Mutación , Regiones Promotoras Genéticas , VertebradosRESUMEN
The novel bromoacetyl ecdysteroid IV, (20R,22R)-2 beta,3 beta,14 alpha,20,22,25 xi-hexahydroxy-26-(3- bromoacetoxypropyl)-5 beta-cholest-7-en-6-one, BAEIV, has been synthesized by extending the side chain on C26 of 20-OH-ecdysone. BAEIV meets all the requirements for an affinity-labelling reagent. It reacts with the partially purified ecdysteroid receptors of Drosophila melanogaster rapidly and almost quantitatively. Reactions require only micromolar concentrations of BAEIV. The rate of the affinity-labelling reaction is determined by the association of BAEIV with the ecdysteroid receptor. The value of the apparent reaction rate constant is very similar to that of the association rate constant for the binding of 20-OH-ecdysone to the ecdysteroid receptor. Product analysis of the reaction of [14C]BAEIV with the ecdysteroid receptor revealed two labelled peptides having molecular masses 150 kDa and 90 kDa. The smaller peptide is possibly a proteolytic fragment of the larger peptide. The identification of a 150-kDa peptide by chemical affinity labelling of the ecdysteroid receptor agrees with previously reported photoaffinity-labelling results from our laboratory. The results also demonstrate that the ecdysteroid receptor of D. melanogaster has a molecular mass higher than all other vertebrate steroid hormone receptors studied so far.
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Marcadores de Afinidad , Drosophila melanogaster/metabolismo , Ecdisterona/análogos & derivados , Receptores de Esteroides/metabolismo , Marcadores de Afinidad/síntesis química , Animales , Núcleo Celular/metabolismo , Cromatografía de Afinidad , Citosol/metabolismo , Ecdisterona/síntesis química , Ecdisterona/metabolismo , Cinética , Peso Molecular , Pupa , Receptores de Esteroides/aislamiento & purificación , Relación Estructura-ActividadRESUMEN
Diagnosis of intrapulmonary Kaposi's sarcoma in HIV-infected patients may be extremely difficult. This is demonstrated in a case of a male patient with disseminated Kaposi's sarcoma and lethal pulmonary involvement. The value of various diagnostic procedures is discussed.