排序方式: 共有18条查询结果,搜索用时 15 毫秒
11.
12.
Korhan Özkan Erik Jeppesen Martin Søndergaard Torben L. Lauridsen Lone Liboriussen Jens-Christian Svenning 《Hydrobiologia》2013,710(1):173-187
Understanding of the forces driving the structure of biotic communities has long been an important focus for ecology, with implications for applied and conservation science. To elucidate the factors driving phytoplankton genus richness in the Danish landscape, we analyzed data derived from late-summer samplings in 195 Danish lakes and ponds in a spatially-explicit framework. To account for the uneven sampling of lakes in the monitoring data, we performed 1,000 permutations. A random set of 131 lakes was assembled and a single sample was selected randomly for each lake at each draw and all the analyses were performed on permuted data 1,000 times. The local environment was described by lake water chemistry, lake morphology, land-use in lake catchments, and climate. Analysis of the effects of four groups of environmental factors on the richness of the main groups of phytoplankton revealed contrasting patterns. Lake water chemistry was the strongest predictor of phytoplankton richness for all groups, while lake morphology also had a strong influence on Bacillariophyceae, Cyanobacteria, Dinophyceae, and Euglenophyceae richness. Climate and land-use in catchments contributed only little to the explained variation in phytoplankton richness, although both factors had a significant effect on Bacillariophyceae richness. Notably, total nitrogen played a more important role for phytoplankton richness than total phosphorus. Overall, models accounted for ca. 30% of the variation in genus richness for all phytoplankton combined as well as the main groups separately. Local spatial structure (<30 km) in phytoplankton richness suggested that connectivity among lakes and catchment-scale processes might also influence phytoplankton richness in Danish lakes. 相似文献
13.
Cluster Computing - The concept of the Internet of Things (IoT) arises due to the change in the characteristics and numbers of smart devices. Communication of things makes it important to ensure... 相似文献
14.
Ongun Sevindik Tuğba Erdoğan Mehmet Tunca Hatice Güzel Uğur Erturaç Mehmet Korhan 《Aquatic Ecology》2022,56(3):697-718
Aquatic Ecology - Phytoplankton biomass, diversity, functional groups (FGs), and environmental parameters in three shallow lakes were evaluated to show the inter-annual fluctuations in... 相似文献
15.
16.
Peyda Korhan Esra Erdal Emine Kandemi? Murat ?okakl? Deniz Nart Funda Y?lmaz Alp Can Ne?e Atabey 《PloS one》2014,9(8)
c-Met, the receptor for Hepatocyte Growth Factor (HGF), overexpressed and deregulated in Hepatocellular Carcinoma (HCC). Caveolin 1 (CAV1), a plasma membrane protein that modulates signal transduction molecules, is also overexpressed in HCC. The aim of this study was to investigate biological and clinical significance of co-expression and activation of c-Met and CAV1 in HCC. We showed that c-Met and CAV1 were co-localized in HCC cells and HGF treatment increased this association. HGF-triggered c-Met activation caused a concurrent rise in both phosphorylation and expression of CAV1. Ectopic expression of CAV1 accelerated c-Met signaling, resulted in enhanced migration, invasion, and branching-morphogenesis. Silencing of CAV1 downregulated c-Met signaling, and decreased migratory/invasive capability of cells and attenuated branching morphogenesis. In addition, activation and co-localization of c-Met and CAV1 were elevated during hepatocarcinogenesis. In conclusion reciprocal activating crosstalk between c-Met and CAV1 promoted oncogenic signaling of c-Met contributed to the initiation and progression of HCC. 相似文献
17.
Sah Dinesh Kumar Nguyen Tu N. Cengiz Korhan Dumba Braulio Kumar Vikas 《Cluster computing》2022,25(3):1715-1727
Cluster Computing - The Industrial Internet of Things uses intelligent sensors to collect the physical properties of objects placed on a large area. It provides innovative service and network... 相似文献
18.
İbrahim Kaan Özgencil Meryem Beklioğlu Korhan Özkan Çağatay Tavşanoğlu Niccolò Fattorini 《Freshwater Biology》2020,65(11):1845-1857
- Water level and submerged macrophytes are critical players for the functioning of shallow lake ecosystems; understanding how waterbird communities respond to changes in both can have important implications for conservation and management. Here, we evaluated the effects of changes in water level and submerged macrophyte status on wintering waterbird community size, functional group abundances, functional diversity (FD), and community assembly by using a dataset compiled over 50 years.
- We built generalised linear models to evaluate the effects of water level and submerged macrophyte status on the above-listed attributes of the waterbird communities by using mid-winter waterbird censuses, water level measurements, and submerged macrophyte surveys, along with submerged macrophyte macrofossil records from two shallow lakes in Turkey. Using a relevant set of functional traits, we defined functional groups, calculated four FD measures, and simulated null distributions of the FD measures for assessing assembly rules.
- We found that macrophyte-dominated years had significantly higher abundances of waterbirds in one of the study lakes, and had more diving herbivores and omnivores in both lakes, while diving/scooping fish-eating waterbird abundance was lower in macrophyte-dominated years. Community size in Lake Beyşehir exhibited a negative association with water level; surprisingly, however, none of the functional group abundances and FD indices were significantly related to water level.
- In our study communities, standardised effect sizes of functional richness and functional dispersion—two indices that are particularly sensitive to community assembly processes—were mostly lower than those of randomly assembled communities, which implies functional clustering. Shifts to a scarce-macrophyte state were associated with increases in these two indices, possibly due to either changes in the relative strength of environmental filtering and limiting similarity in community assembly or sampling of transitional communities. Further studies covering a wider range of the trophic/macrophyte status spectrum are needed to be certain.
- The results of this study indicate that shifts between abundant and scarce-macrophyte states can have significant effects on wintering waterbird abundances, FD and community assembly. The results also suggest that shallow lakes in macrophyte-dominated states can support more wintering waterbirds, especially diving omnivores, some of which are globally threatened.