résorption foliaire de l'azote et du phosphore dans une forêt non perturbée et dans une forêt plantée de Pinus pinaster ait. dans le nord de la turquie. -La résorption foliaire est étroitement liée à la sénescence et à la conservation des nutriments et protège la plante dans sa dépendance des apports du sol. Dans la présente étude, ont été étudiées dans le nord-est de la Turquie la dynamique foliaire de l'azote (N) et du phosphore (P), l'efficacité (RE) et la profitabilité (RP) de la résorption foliaire de quelques plantes décidues existant dans une forêt non perturbée et dans une autre plantée en Pinus pinaster Ait. En forêt non perturbée, on n'a pas observé de différences entre les espèces pour ce qui concerne l'efficacité et la profitabilité alors qu'en forêt plantée en P. pinaster des différences statistiquement significatives ont été notées entre les espèces pour ce qui concerne la NRE, la NRP et la CRE. La CRE est apparue plus élevée que chez les angiospermes et graminoïdes ligneux sempervirents présents dans la zone d'étude. La NRE était plus forte en forêt non perturbée qu'en forêt plantée en P. pinaster. Dans les deux forêts la résorption foliaire de l'azote et du phosphore était biochimiquement complète. Il a été trouvé que la limitation en phosphore se produisait dans les plantes décidues des deux forêts au niveau des rapports N/P durant la sénescence foliaire. De même, le rapport C/N s'est avéré élevé durant la sénescence. En forêt plantée en P. pinaster le rapport N/P et la NRE (tant en masse qu'en surface) sont apparus plus faibles qu'en forêt non perturbée.SUmmARY. -Foliar resorption is closely associated with leaf senescence and conservation of nutrients, and protects the plant dependence on soil supply. In this study, leaf nitrogen (N) and phosphorus (P) dynamics, leaf resorption efficiency (RE) and resorption proficiency (RP) in some deciduous plants occurring in an undisturbed forest and a Pinus pinaster Ait. planted forest were investigated in northeastern Turkey. There were no significant differences among species with respect to foliar resorption efficiency and proficiency in undisturbed forest, whilst statistically significant differences were found among species regarding NRE, NRP and CRE in P. pinaster planted forest. CRE was found to be higher than for evergreen woody angiosperms and graminoids present in the study area. NRE was higher in undisturbed forest than in P. pinaster planted forest. In both forests foliar nitrogen and phosphorus resorption were biochemically complete. It was found that phosphorus limitation occurred in deciduous plants in both forests with respect to N/P ratios during leaf senescence. Similarly, C/N ratio was found to be high during senescence. In P. pinaster planted forest N/P ratio and NRE (both mass-and area-based) were found to be low as compared to undisturbed forest.Forests and tree plantations are increasingly considered for their central role as providers of habitat and regulators of global biogeochemical, temperature and water cycles. Forest

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B u çalışmada, farklı lokalitelerdeki Alcea apterocarpa (Fenzl) Boiss popülasyonlarının yaprak alanı ve spesifik yaprak ağırlığı değerlerini karşılaştırdık. SLA ve LMA önemli yaprak karakterleridir. Çünkü SLA ve LMA yaprak besinleri, yaprak ekonomisi ve atmosferle gaz alışverişlerinde ilişkilidir. Bu nedenle bir çok tür yaprak karakterlerini çevresel gradientlere karşı uyarlamaktadır. A. apterocarpa ruderal bir türdür ve geniş yayılış alanlarına sahiptir. Ayrıca etnobotanik özelliğe sahip olan örnek tedavi edici bitki özelliğine sahiptir. Çalışma için üç farklı lokalitede 6 birey seçtik. Her bir lokalite farklı nüfus yoğunluğuna sahip bölgelerden seçilmiştir. Lokalitelerden olgun ve senesens yapraklar toplanmış ve yaprakların SLA ve LMA değerleri hesaplanmıştır. Sonuçlar, senesens ile olgun yapraklar ve lokaliteler arasında önemli farklılıkların olduğunu göstermiştir. Özellikle, şehir merkezindeki A. apterocarpa populasyonunda SLA değeri diğer lokalitelere göre en yüksek iken, LMA değeri en düşük bulunmuştur.

The study goal is to reveal foliar resorption patterns of Alcea apterocarpa populations in different habitats (riverbank, meadow and forest clearing) in the Central Black Sea Region of Turkey. We determined foliar nitrogen and phosphorus resorption, considering proficiency and efficiency. The resorption efficiency was also calculated using the mass loss correction factor (MLCF). Some studies indicated that MLCF provides unbiased resorption values. Phosphorus resorption proficiencies (PRP) of species were intermediate level, while nitrogen resorption proficiencies (NRP) were complete level. Phosphorus resorption efficiencies (PRE) were intermediate level for all habitats considering MLCF, while in meadow habitat, PRE was complete level without MLCF. Nitrogen resorption efficiencies (NRE) were intermediate level for all habitats without MLCF, but NRE values of meadow and forest clearing were incomplete level as using MLCF. Green leaf N/P ratios of A. apterocarpa were higher in riverbank, while senescence leaf N/P ratios were higher in meadow habitat. Only, the regression relationship between PRP and green leaf N/P ratio was not significant.

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In his dystopian novel, Extinction (2005), Ray Hammond envisions an image of the world in the near future where it is troubled by an extreme form of climate management that enables multi-national corporations and governments from the wealthier regions of the world to control the climate and make profits by selling climate services to the rest of the world. The invasive climate management practices of the capitalist system represented by corporations and governments interfere with and disrupt the natural rhythms of the Earth systems to the extent of the latter's collapse. Moreover, the representatives of the capitalist self-prioritizing system such as the ERGIA Corporation and the US Government in the novel spread ignorance regarding the true nature of their practices by suppressing and/or obscuring scientific findings and evidence that prove the harmful effects of their relentless climate management. Accordingly, this paper aims at tracing the links between the perpetuated practices of the capitalist corporations and governments, and environmental degradation and collapse in Ray Hammond's Extinction which presents a world where advanced climate management systems have been implemented in space and weather events are tightly controlled and scheduled. It further discusses how the environmental cataclysms brought about by deep interference with the Earth's magnetic field via extreme climate management in the novel expose the self-interested and ruthless capitalist system's failure to see or rather deliberate ignorance of the detrimental and irreversible effects and consequences of large-scale climate management which drives the world to extinction.

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Aim: Elabela (ELA) is a peptide of the apelinergic system and is known to play a role in endothelial homeostasis and vascular pathobiology. In this study, the relationship between carotid artery stenosis, which is the main culprit, and ELA level in patients with non-cardioembolic ischemic stroke was investigated. Materials & methods: Cross-sectional observation included two groups of 40 patients with critical carotid artery stenosis and 40 patients with age–sex matched noncritical carotid artery stenosis. Results: ELA levels were significantly higher in the noncritical stenosis group. ELA had a significantly moderate negative correlation with the carotid score (r = -0.334, p = 0.003), maximal carotid plaque length (r = -0.413, p < 0.001) and degree of stenosis (r = -0.397, p < 0.001). Conclusions: There is a significant inverse correlation between critical carotid artery disease and ELA level in patients with non-cardioembolic ischemic stroke.