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1.
Ecol Appl ; 31(5): e02332, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33765327

RESUMEN

Many organisms respond to anthropogenic environmental change through shifts in their phenology. In plants, flowering is largely driven by temperature, and therefore affected by climate change. However, on smaller scales climatic conditions are also influenced by other factors, including habitat structure. A group of plants with a particularly distinct phenology are the understory herbs in temperate European forests. In these forests, management alters tree species composition (often replacing deciduous with coniferous species) and homogenizes stand structure, and as a consequence changes light conditions and microclimate. Forest management should thus also affect the phenology of understory herbs. To test this, we recorded the flowering phenology of 16 early-flowering herbs on 100 forest plots varying in management intensity, from near-natural to intensely managed forests, in central and southern Germany. We found that in forest stands with a high management intensity, such as Norway spruce plantations, the plants flowered on average about 2 weeks later than in unmanaged forests. This was largely because management also affected microclimate (e.g., spring temperatures of 5.9°C in managed coniferous, 6.7 in managed deciduous, and 7.0°C in unmanaged deciduous plots), which in turn affected phenology, with plants flowering later on colder and moister forest stands (+4.5 d per -1°C and 2.7 d per 10% humidity increase). Among forest characteristics, the percentage of conifers had the greatest influence on microclimate, but also the age, overall crown projection area, structural complexity and spatial distribution of the forest stands. Our study indicates that forest management alters plant phenology, with potential far-reaching consequences for the ecology and evolution of understorey communities. More generally, our study demonstrates that besides climate change other drivers of environmental change, too, can influence the phenology of organisms.


Asunto(s)
Cambio Climático , Árboles , Ecosistema , Flores , Estaciones del Año
2.
Glob Chang Biol ; 24(1): e289-e302, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28833915

RESUMEN

Across the globe, invasive alien species cause severe environmental changes, altering species composition and ecosystem functions. So far, mountain areas have mostly been spared from large-scale invasions. However, climate change, land-use abandonment, the development of tourism and the increasing ornamental trade will weaken the barriers to invasions in these systems. Understanding how alien species will react and how native communities will influence their success is thus of prime importance in a management perspective. Here, we used a spatially and temporally explicit simulation model to forecast invasion risks in a protected mountain area in the French Alps under future conditions. We combined scenarios of climate change, land-use abandonment and tourism-linked increases in propagule pressure to test if the spread of alien species in the region will increase in the future. We modelled already naturalized alien species and new ornamental plants, accounting for interactions among global change components, and also competition with the native vegetation. Our results show that propagule pressure and climate change will interact to increase overall species richness of both naturalized aliens and new ornamentals, as well as their upper elevational limits and regional range-sizes. Under climate change, woody aliens are predicted to more than double in range-size and herbaceous species to occupy up to 20% of the park area. In contrast, land-use abandonment will open new invasion opportunities for woody aliens, but decrease invasion probability for naturalized and ornamental alien herbs as a consequence of colonization by native trees. This emphasizes the importance of interactions with the native vegetation either for facilitating or potentially for curbing invasions. Overall, our work highlights an additional and previously underestimated threat for the fragile mountain flora of the Alps already facing climate changes, land-use transformations and overexploitation by tourism.


Asunto(s)
Altitud , Cambio Climático , Ecosistema , Especies Introducidas , Plantas/clasificación , Simulación por Computador , Demografía , Humanos , Modelos Biológicos , Viaje
3.
J Endourol ; 28(11): 1384-8, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24935738

RESUMEN

OBJECTIVE: To show the benefit of trocar-sharpened needles for image-guided prostate biopsy compared with standard bevelled needles in patients. MATERIALS AND METHODS: Twenty-four men underwent magnetic resonance imaging-targeted fusion-guided transperineal saturation prostate biopsy, each with half standard bevelled and half trocar-sharpened needles. All taken biopsies were scored (1=worse to 5=best) by one urologist for the following criteria. (1) Accuracy of matching between planned and performed biopsy. (2) Histologic quality of the sample. (3) Elegance, which is the easiness to take the biopsy in proper time, planned position, and best histologic quality. Afterward, the histologic sample quality was evaluated by a blinded pathologist. To show a possible training effect, blinded untrained junior residents performed biopsies in four men (103 cores). RESULTS: Overall, 600 single biopsies were analyzed. The trocar-sharpened needles demonstrated a significantly (p<0.05) better scoring for accuracy and elegance rated by the urologist. The histologic quality scored by the pathologist was superior. Moreover, significantly lower target errors with trocar-sharpened needles were achieved by untrained residents, but not by the experienced user. CONCLUSION: Using trocar-sharpened needles helps urologists to perform targeted prostate biopsy more elegantly and accurately. In addition, the histopathologic sample quality was superior, which may directly improve diagnostic certainty. There is an undeniable training effect in image-guided biopsy and unexperienced users can significantly reduce target errors with trocar-sharpened needles.


Asunto(s)
Biopsia con Aguja/instrumentación , Biopsia Guiada por Imagen/instrumentación , Neoplasias de la Próstata/diagnóstico , Anciano , Biopsia con Aguja/métodos , Biopsia con Aguja/normas , Humanos , Biopsia Guiada por Imagen/métodos , Biopsia Guiada por Imagen/normas , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Neoplasias de la Próstata/patología
4.
Bioorg Med Chem Lett ; 21(14): 4276-80, 2011 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-21689933

RESUMEN

A high throughput screening campaign identified aryl 1,4-diazepane compounds as potent and selective cannabinoid receptor 2 agonists as compared to cannabinoid receptor 1. This class of compounds suffered from poor drug-like parameters as well as low microsomal stability and poor solubility. Structure-activity relationships are described with a focus on improving the drug-like parameters resulting in compounds with improved solubility and permeability.


Asunto(s)
Azepinas/química , Receptor Cannabinoide CB2/agonistas , Azepinas/farmacología , Células CACO-2 , Permeabilidad de la Membrana Celular , Ensayos Analíticos de Alto Rendimiento , Humanos , Microsomas Hepáticos/metabolismo , Receptor Cannabinoide CB1/agonistas , Receptor Cannabinoide CB1/metabolismo , Receptor Cannabinoide CB2/metabolismo , Solubilidad , Relación Estructura-Actividad
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