Search results for "Fragmentation"
showing 10 items of 798 documents
Dryofragin, a phloroglucinol derivative, induces apoptosis in human breast cancer MCF-7 cells through ROS-mediated mitochondrial pathway
2012
Dryofragin is a phloroglucinol derivative extracted from Dryopteris fragrans (L.) Schott. In this study, the anticancer activity of dryofragin on human breast cancer MCF-7 cells was investigated. Dryofragin inhibited the growth of MCF-7 cells in a time and concentration-dependent manner. The cell viability was measured using MTT assay. After treatment with dryofragin for 72, 48 and 24 h, the IC₅₀ values were 27.26, 37.51 and 76.10 μM, respectively. Further analyses of DNA fragmentation and Annexin V-PI double-labeling indicated an induction of apoptosis. Dryofragin-treatment MCF-7 cells had a significantly accumulation of reactive oxygen species (ROS), as well as an increased percentage of …
Connected Lands : new perspectives on Ecological Networks Planning
2017
The construction of an ecological network is a fairly complex operation, given that the components to be considered are strictly linked to the age-old problem of the relationship between man and the land, until now perhaps seen too much as a limiting relationship and not, as the use of this tool suggests, as a relationship to be safeguarded. It may represent the ideal way to reconcile human needs and the conservation of biodiversity for the sustainable management of land. This study on the ecological network represents a tool capable to contain habitat fragmentation trough a new perspective that integrates theoretical approaches and methods with planning models and experiences of local appl…
Caractérisation de la connectivité des habitats du petit rhinolophe en Franche-Comté
2011
National audience
The fall and the fragmentation of national clusters: Cluster evolution in the paper and pulp industry
2012
Abstract A common expectation in evolutionary cluster studies is that national clusters engage in competitive interactions that lead to a continuous stream of changes in global dominance. Our fuzzy-set analysis on the evolution of the paper and pulp industry demonstrates that globalization has dramatically changed this situation. National clusters have largely faded away; the value chain dominance is now held by technology suppliers who are global hubs in majority of identifiable business activities in the focal industry. Our results imply that when industrial decline is accentuated by industrial concentration in some part of the value chain the national clusters may lose their importance.
Forest Fragmentation Increases Nest Predation in the Eurasian Treecreeper
2004
We used long-term breeding data to monitor the influences of fragmentation and habitat composi- tion at different spatial scales on the reproductive success of Eurasian Treecreepers (Certhia familiaris) breeding in nest boxes. We collected data from the same forest patches (2.7-65.1 ha in size) during seven breeding sea- sons. Nest predation varied considerably over the years and was the primary cause of nesting failure (mean annual rate of 21.6 ± 12.8%). Nest predation explained most of the variation in fledgling production during the study period. Landscape-level fragmentation (radius of 500 m from territory center) affected nest predation more than did fragmentation on the territory scal…
Final Assessment of the EU-Africa Trade Deals—Ways Out?
2021
Based on the emerging country configurations (EPA groups) and the content of the EU-Africa trade arrangements, the chapter reviews the political impasse between the EU and Africa following the highly contested implementation start of the bi-regional trade agreements. Regional economic integration in Africa is considered to be in present danger with regard to the engendered fragmentation of main African RECs, namely the emerging customs unions. Suggestions are reviewed on how these and other North-South agreements can be either replaced by treaties that will be more beneficial for African countries and regions (‘grand alternatives’) or at least substantially improved (‘repair work’). New are…
Oxygen K-shell spectroscopy of isolated progressively solvated peptide
2020
Gas-phase near-edge X-ray-absorption fine structure (NEXAFS) action spectroscopy around the oxygen K-edge and mass spectrometry were employed to probe isolated substance P (SP) molecular ions, both bare and progressively solvated with 4 and 11 water molecules. Detailed mass spectra of bare and hydrated precursors are presented for the resonant photon energy of 532 eV that corresponds to O1s --> pi(amide)* core excitation, triggering resonant Auger decay and fragmentation from the ionized radical molecular system. The fragmentation pattern of doubly protonated SP hydrated with 4 water molecules clearly shows a series of abundant doubly charged backbone fragments, as well as triply charged pr…
ETD and ECD Mass Spectrometry Fragmentation for the Characterization of Protein Post Translational Modifications
2012
The introduction of electron capture dissociation (ECD) by McLafferty and co-workers, and further of electron transfer dissociation (ETD), mechanism allows gas-phase fragmentation of multiply charged protein and peptide ions upon capture of a low-energy (<1 eV) electron or electron transfer in a gas phase ion-ion chemistry. The odd-electron species then undergoes rearrangement with subsequent cleavage of N−Cα backbone. Peptide fragmentation can take place inducing the formation of cand ztype fragment ions without loss of the information on the PTM localization. The key to the success of this approach is the selection of intact protein molecular ions and its profound potential for PTM charac…
Detection of primary DNA damage in Chlamydomonas reinhardtii by means of modified microgel electrophoresis.
1997
The assessment of genotoxic potential in surface water requires test methods, among which are those that detect initial DNA damage in organisms of aquatic biocenosis. The microgel electrophoresis (MGE) "comet assay" was applied to a ubiquitous unicellular green alga (Chlamydomonas reinhardtii) to detect DNA damage caused by genotoxins. For this, the test protocol described by Singh NP et al. [Exp Cell Res 175: 184-191, 1988] was modified. Major modifications were the use of alkaline lysis buffer with ionic detergents and the reduction of preincubation and electrophoresis times. Short-time exposure of Chlamydomonas to the well-known genotoxicants 4-nitroquinoline-1-oxide (4-NQO), N-nitrosodi…
Study of the Fragmentation of D-Glucose and Alkylmonoglycosides in the Presence of Sodium Ions in an Ion-Trap Mass Spectrometer
2009
Abstract Using electrospray ion-trap mass spectrometry, the fragmentation of D-glucose and alkylmonoglycopyranosides (alkyl-GPs) was studied. In the presence of Na+, B1 and 0,2A fragmentations were observed. The alkyl-GPs also showed a 2,5Afragmentation. A cluster containing no carbon atoms and adducts of this cluster with neutral molecules were observed. Standards of alkylmonoglycofuranosides (alkyl-GFs) were not available; however, their fragmentation was studied by high-performace liquid chromatography–mass spectrometry (HPLC-MS) and HPLC-MS2 using an industrial mixture of alkylpolyglycosides. The cluster and its adducts were more easily formed by the alkyl-GPs than by the alkyl-GFs, but…