Search results for "Dike"
showing 10 items of 88 documents
The ‘killer shrimp’Dikerogammarus villosus(Crustacea, Amphipoda) invading Alpine lakes: overland transport by recreational boats and scuba-diving gea…
2013
The alien freshwater amphipod of Ponto-Caspian origin, Dikerogammarus villosus, also known as the killer shrimp, is recognized as being one of the worst invasive alien species in Europe, representing a major conservation problem. Recently, the species has been reported to invade lakes in the Alps in putative association with overland transport linked with recreational activities. This study provided a method to assess risk associated with this overland transport and an opportunity to set up a rationale for effective preventive conservation management. A field survey of 60 lakes encompassing all the Alpine area has revealed the presence of killer shrimp in 12 lakes. Subsequent multivariate d…
Isolation and characterization of 8 microsatellite loci for the "killer shrimp'', an invasive Ponto-Caspian amphipod Dikerogammarus villosus (Crustac…
2015
5 pages; International audience; Dikerogammarus villosus is a freshwater amphipod of the Ponto-Caspian origin recognized as one of the 100 worst alien species in Europe, having negative impact on biodiversity and functioning of the invaded aquatic ecosystems. The species has a wide ecophysiological tolerance and during the last 20 years it has rapidly spread throughout European inland waters. In consequence, it presents a major conservation management problem. We describe eight polymorphic microsatellite loci developed for D. villosus by combining a biotin-enrichment protocol and new generation 454GS-FLX Titanium pyrosequencing technology. When genotyped in 64 individuals from two locations…
Dikerogammarus villosus (Sowinsky, 1894) (Crustacea, Amphipoda) colonizes next alpine lake – Lac du Bourget, France
2007
Dikerogammarus villosus has been recorded for the first time in the alpine lake – Lac du Bourget, French Alps. Low abundance of the alien species in gathered samples suggests that the colonization is just in its initial stage. Two native gammarid species: Gammarus fossarum (Koch, 1835) and G. pulex (Linnaeus, 1758) are still present in the lake. The invader has most probably reached the lake through the Canal de Savieres joining the lake to the Rhone River in which it has been already present since late 1990s.
Comparison of the functional responses of invasive and native amphipods
2008
While we can usually understand the impacts of invasive species on recipient communities, invasion biology lacks methodologies that are potentially more predictive. Such tools should ideally be straightforward and widely applicable. Here, we explore an approach that compares the functional responses (FRs) of invader and native amphipod crustaceans. Dikerogammarus villosus is a Ponto-Caspian amphipod currently invading Europe and poised to invade North America. Compared with other amphipods that it actively replaces in freshwaters, D. villosus exhibited significantly greater predation, consuming significantly more prey with a higher type II FR. This corroborates the known dramatic field imp…
La giustizia valore supremo presso i Greci?
2020
Nella Grecia antica, la giustizia (il limitarsi passivamente a non fare il male e a rispettare i diritti altrui) è certamente un valore necessario ma spesso non è riconosciuto come valore sufficiente per la vita nella polis. Per tutta una linea di pensiero alla giustizia bisogna aggiungere, come integrazione indispensabile, la virtù attiva del curarsi degli altri. Altrimenti, si avrà un’aggregazione associativa, una somma di individui che si limitano a trattenersi dal compiere ingiustizia ma non si avrà comunità umana, che è solidarietà, ovvero aidós e philía, rispetto e amicizia In ancient Greece, justice (limiting oneself passively to respect the rights of others) is certainly a necessary…
Syn- and post-eruptive mechanism of the Alaskan Ukinrek Maars in 1977
2008
The two alkali olivine basaltic Ukinrek Maars (East Maar and West Maar) and one scoria cone within East Maar erupted within eleven days (March 30–April 9, 1977) on the Alaskan Peninsula, 13 km north of Mt. Peulik, an andesite volcano of the Aleutian Range. The East Maar, with a diameter of 300 m, is located within a small graben system striking N 1100 E, oblique to the Aleutian trench in a distance of 350 km. On these tensional faults two eruption centres occur: The East Maar and a scoria cone on the southeastern margin of its crater bottom. The scoria cone was active more or less during the whole eruption activity of East Maar. The West Maar, with a diameter of 140 m, is located just west …
Investigation of Diketopiperazines Containing a Guanidino-Functionalized Sidechain as Potential Catalysts of Enantioselective Strecker Reactions
2005
Diketopiperazine 1 consisting of L-(γ-guanidino-α-amino)butyric acid and L-phenylalanine was synthesized as the hydroacetate and as the hydronitrate. Its structure was confirmed by X-ray analysis. In contrast to reports in the literature (Lipton et al.), compound 1 does not induce enantioselevtive catalysis of Strecker reactions. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Synthesis and Antitumor Properties of 2,5-Bis(3'-indolyl) thiophenes: Analogues of Marine Alkaloid Nortopsentin
2007
A series of 11 bis-indolylthiophenes of formula I were obtained by cyclization of bis-indole 1,4-diketones using Lawesson''s reagent. Derivs. I (R = OMe, R1 = SO2Ph), I (R = OMe, R1 = Me), I (R = Cl, R1 = Me), and I (R = OMe, R1 = H) were selected to be evaluated in the full panel of about 60 human tumor cell lines derived from nine human cancer cell types and showed antiproliferative activity generally in the micromolar range. The most sensitive cell lines were: CCRF-CEM, MOLT-4, HL60 (TB), and RPMI-8226 of the leukemia subpanel, HT29 and HCC-2998 cell lines of the colon sub-panel, NCI-H522 of the non-small cell lung cancer sub-panel, LOX IMVI of the melanoma sub-panel, and UO-31 of the re…
The Question of Providence and the Problem of Evil in Suhrawardī
2021
Abstract Šihāb al-Dīn al-Suhrawardī’s philosophical works seem to contain two conflicting views on providence: in the Talwīḥāt and the Mašāriʿ, he endorses the Avicennian view, only to deny providence altogether in the Ḥikmat al-išrāq. This contribution aims to explain the seeming inconsistency by investigating it in light of the underlying question of God’s knowledge of particular things. I will also argue that despite his qualms concerning providence, Suhrawardī accepts the closely related Avicennian answer to the problem of evil.
Lack of nucleophilic addition in the isoxazole and pyrazole diketone modified analogs of curcumin; implications for their antitumor and chemosensitiz…
2009
Curcumin (CUR) can be considered as a good lead compound for the design of new anticancer drugs. Further, structure-activity relationship studies may clarify the importance of the redox activities in the antitumor effects of the drug. We have elaborated the alpha,beta-unsaturated 1,3-diketone moiety of CUR into the isoxazole (ISO) and pyrazole (PYR) derivatives. These derivatives should be much less prone to nucleophilic addition than CUR and benzyl mercaptan addition analyses showed that indeed they do not form isolable conjugated products. When compared with CUR, ISO and PYR exhibited increased cell growth inhibitory and pro-apoptotic effects in liver cancer HA22T/VGH cells as well as in …