131,872 research outputs found
Bergamini, D. and The Editors of Life. The Land and Wildlife of Australia. New York, Time, 1964, Life Nature Library
No full textPfeffer Pierre. Bergamini, D. and The Editors of Life. The Land and Wildlife of Australia. New York, Time, 1964, Life Nature Library. In: La Terre et La Vie, Revue d'Histoire naturelle, tome 18, n°2, 1964. pp. 228-229
Diaphanosoma bergamini Paggi
No full textDiaphanosoma bergamini Paggi & da Rocha, 1999 (Figs. 2–8) Material examined: Many parthenogenetic females from Silvituc lagoon. Body 0.60–0.70 mm, elongate. Head small, slightly directed downward. Second antenna almost reaching posterior margin of valves (Fig. 2). Ventral margin of valves with a wide inflexion, armed with several thin setae (Fig. 3). A dorsal spine with long setules near posterior margin of valves (Fig. 4). Antennal setae 4–7 / 0–1 – 4, spines 1 – 1 / 0–1 – 1 (Fig. 5). Rows of fine spinules on lateral side of postabdomen. Postabdominal claws armed laterally with two rows of fine denticles (Fig. 8) and three long spines on the base, two of them wavy. Diaphanosoma bergamini was described from the Amazon and Orinoco basins in Venezuela (Paggi & da Rocha, 1999), under the generic name Neodiaphanosoma Paggi & da Rocha, 1999. This genus was based on a numerical phenetic analysis, and supported mainly by the presence of a long fingerlike sensillum at the tip of twosegmented antennal branch (Fig. 5, arrow). However, we agree with Korovchinsky (2004) that separation of the genus Neodiaphanosoma is not justified, because all characters proposed to support the genus Neodiaphanosoma are present in other species of the genus Diaphanosoma, and the only specific feature is the presence of the fingerlike seta. Silvituc is the northernmost locality of this rare species, which is closely related to Diaphanosoma volzi Stingelin from the Old World. According to Paggi & da Rocha (1999), both taxa have restricted their distribution to the tropics and subtropics, but apparently some other unknown factors limit their distribution inside this geographical range, at least for D. bergamini, since we have not detected it in any other system in the studied region. It was coexisting with Diaphanosoma brevireme Sars, a much more common species in this area.Published as part of Elías-Gutiérrez, Manuel, Kotov, Alexey A. & Garfias-Espejo, Tania, 2006, Cladocera (Crustacea: Ctenopoda, Anomopoda) from southern Mexico, Belize and northern Guatemala, with some biogeographical notes, pp. 1-27 in Zootaxa 1119 on page 7, DOI: 10.5281/zenodo.17167
“The highly reducing sugar 2-deoxy-d-ribose induces apoptosis in human fibroblasts by reduced glutathione depletion and cytoskeletal disruption”
No full text2-deoxy-D-Ribose (dRib), the most reducing sugar, induces apoptosis in normal human fibroblasts, as judged by cytoplasmic shrinkage, chromatin condensation, DNA fragmentation and mitochondrial depolarization. This effect is independent from culture conditions, such as cell density and the presence or absence of serum in the culture milieu, suggesting that dRib-induced apoptosis is cell cycle-independent. dRib was found also to provoke disruption of the actin filament network and detachment from the substratum, while at the same time, interestingly, it increases the expression of several integrins and cell adhesion molecules. Furthermore, dRib was found to reduce the intracellular levels of reduced glutathione (GSH). The apoptotic process was not affected by the macromolecular-synthesis inhibitors cycloheximide and actinomycin D. On the contrary, the antioxidant N-acetyl-L-cysteine (NAG) fully blocks the dRib-induced apoptosis by preventing GSH depletion, while it also inhibits actin-filament-network disruption and mitochondrial depolarization. The above indicate that dRib induces apoptosis in human fibroblasts by a mechanism involving glutathione metabolism and oxidative stress, as well as disturbance of cytoskeletal integrity and cell adhesion
Spariscono una serie di disposizioni discriminatorie (commento al d. lgs di attuazione della direttiva servizi)
No full text
Patterns of activity of nucleolar organizer regions during spermatogenesis and oogenesis in Kalotermes flavicollis Fabr. (Insecta: Isoptera) analyzed by silver staining
No full textThe distribution and the behaviour of the nucleolus organizer regions (NORs) were analysed during the spermatogenesis and oogenesis of K. flavicollis with the silver staining method. The Ag-stainability of the NORs increases in growing spermatocytes up to pachytene and is absent during the remainder of the meiotic prophase. During female meiosis the nucleolar material undergoes a more complex transformation. It is active until pachytene; in early diplotene the mass of silver stainable material progressively increases as an effect of rDNA amplification. By the end of meiotic prophase the nucleolar strands disappear and a large nucleolus is rebuilt in the mature oocyte
MeSH term explosion and author rank improve expert recommendations
No full textInformation overload is an often-cited phenomenon that reduces the productivity, efficiency and efficacy of scientists. One challenge for scientists is to find appropriate collaborators in their research. The literature describes various solutions to the problem of expertise location, but most current approaches do not appear to be very suitable for expert recommendations in biomedical research. In this study, we present the development and initial evaluation of a vector space model-based algorithm to calculate researcher similarity using four inputs: 1) MeSH terms of publications; 2) MeSH terms and author rank; 3) exploded MeSH terms; and 4) exploded MeSH terms and author rank. We developed and evaluated the algorithm using a data set of 17,525 authors and their 22,542 papers. On average, our algorithms correctly predicted 2.5 of the top 5/10 coauthors of individual scientists. Exploded MeSH and author rank outperformed all other algorithms in accuracy, followed closely by MeSH and author rank. Our results show that the accuracy of MeSH term-based matching can be enhanced with other metadata such as author rank
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