528 research outputs found
First record of the wood-boring beetles Oxymirus cursor and Sinodendron cylindricum in Greece
Δύο είδη ξυλοφάγων κολεοπτέρων καταγράφηκαν για πρώτη φορά στην Ελλάδα. Στα τέλη του Ιουνίου 2001, το είδος Oxymirus cursor (L.) (Coleoptera: Cerambycidae) της φυλής Oxymirini βρέθηκε στο όρος Ροδόπη, ενώ στις αρχές Αυγούστου 2012 το είδος Sinodendron cylindricum (L.) (Coleoptera: Lucanidae) της φυλής Sinidendrini βρέθηκε στο όρος Φαλακρό, στη Β. Ελλάδα. Παρουσιάζονται εικόνες των δύο ειδών καθώς και πληροφορίες σχετικά με την εξάπλωση τους, την βιολογία και οικολογία τους.Two wood-boring beetles are recorded for the first time in Greece. On late June 2001, the lepturine longicorn beetle Oxymirus cursor (L.) (Coleoptera: Cerambycidae) was found on Mt. Rodopi, and on early August 2012 the lucanid beetle Sinodendron cylindricum (L.) (Coleoptera: Lucanidae) was found on Mt. Falakron, in N. Greece. Images of both species and information on their distribution, ecology and biology, are presented
CD40 Activation Induces Apoptosis in Cultured Human Hepatocytes via Induction of Cell Surface Fas Ligand Expression and Amplifies Fas-mediated Hepatocyte Death during Allograft Rejection
We propose that a novel mechanism of hepatocyte apoptosis, involving a cooperative interaction between CD40 and Fas, is involved in the hepatocyte loss of chronic liver allograft rejection. We detected increased hepatocyte expression of Fas, Fas ligand (FasL), and CD40 associated with dropout of centrilobular (acinar zone 3) hepatocytes in chronic allograft rejection. Expression of CD40 ligand (CD40L) was also increased but was largely restricted to CD68+ macrophages. A functional role for CD40 and Fas in hepatocyte apoptosis was demonstrated in vitro using primary human hepatocytes and the HepG2 cell line in both of which apoptosis was induced, not only by cross-linking Fas directly but also via CD40 activation. Our data suggest that CD40 activation induces apoptosis via Fas because (a) ligation of CD40 upregulated hepatocyte FasL expression, and (b) apoptosis induced via activation of CD40 was prevented by a neutralizing monoclonal antibody to FasL. Thus, CD40 engagement triggers apoptosis of human hepatocytes and might amplify Fas-dependent hepatocyte apoptosis in chronic rejection and other inflammatory liver diseases in which Fas-mediated apoptosis is involved
The effect of temperature on the development of Nephus includens (Kirsch) and Nephus bisignatus (Boheman) (Coleoptera: Coccinellidae), predators of Planococcus citri Risso (Hemiptera: Pseudococcidae)
The effect of temperature οη the development of the predators Nephus includens (Kirsch) and Ν. bisignatus (Boheman) (Coleoptera: Coccinellidae), was studied. The development time of immature stages and the pre-oviposition period of adult females for the two predators was recorded at eight constant temperatures (10, 15, 20, 25, 30, 32.5, 35 and 37.5°C). The beetles were reared on eggs, nymphs and female adults of Planococcus citri (Risso) (Homoptera: Pseudococcidae) that had developed on squash (Cucurbita pepo) and on sour orange leaves (CΊtrus aurantium). Using the linear model for the biological cycle of Ν. includens on squash and on sour orange leaves, the developmental zeros (lower temperature thresholds) were estimated to be 10.9 and 11.0°C respectively and the thermal constants, 490.5 and 472.8 day-degrees respectively. Using the Lactin model the lower thresholds were estimated to be 11.1 and 11.2°C respectively and the upper thresholds 36.1 and 36.0°C respectively. For the biological cycle of Ν. bisignatus, using the linear model, the lower thresholds were estimated to be 9.4°C on squash and 9.3°C on sour orange leaves and the thermal constants were 614.3 and 647.9 day-degrees respectively. Using the Lactin model the lower thresholds were estimated to be 9.9 and 1O.0°C respectively and the upper thresholds, 34.7 and 35.0°C respectively. The survival rate of Ν. includens instars at 10, 15, 20, 25, 30, 32.5, 35 and 37.5°C on squash and on sour orange leaves was respectively 0.0, 34.9, 63.2, 70.6, 63.3, 54.5, 19.8, 0.0, and 0.0, 32.2, 61.0, 68.0, 68.3, 56.6, 17.6, 0.0%. The survival rate of Ν. bisignatus instars at 10, 15, 20, 25, 30, 32.5 and 35°C on squash and on sour orange leaves was respectively, 0.0, 39.9, 61.1, 60.7, 47.2, 26.4, 0.0 and 0.0, 35.7, 65.7, 68.0, 44.2, 29.1, 0.0%. The results show that Ν. includens has a shorter biological cycle than Ν. bisignatus, whereas the latter species has lower temperature thresholds
Manipulating Kondo Temperature via Single Molecule Switching
Two conformations of isolated single TBrPP-Co molecules on a Cu(111) surface
are switched by applying +2.2 V voltage pulses from a scanning tunneling
microscope tip at 4.6 K. The TBrPP-Co has a spin-active cobalt atom caged at
its center and the interaction between the spin of this cobalt atom and free
electrons from the Cu(111) substrate can cause a Kondo resonance. Tunneling
spectroscopy data reveal that switching from the saddle to a planar molecular
conformation enhances spin-electron coupling, which increases the associated
Kondo temperature from 130 K to 170 K. This result demonstrates that the Kondo
temperature can be manipulated just by changing molecular conformation without
altering chemical composition of the molecule.Comment: To appear in Nano Lett (2006
Generalized -conformal change and special Finsler spaces
In this paper, we investigate the change of Finslr metrics which we refer to as a
generalized -conformal change. Under this change, we study some special
Finsler spaces, namely, quasi C-reducible, semi C-reducible, C-reducible,
-like, -like and -like Finsler spaces. We also obtain the
transformation of the T-tensor under this change and study some interesting
special cases. We then impose a certain condition on the generalized
-conformal change, which we call the b-condition, and investigate the
geometric consequences of such condition. Finally, we give the conditions under
which a generalized -conformal change is projective and generalize some
known results in the literature.Comment: References added, some modifications are performed, LateX file, 24
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