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Largest Groups (largest + groups)
Selected AbstractsGalaxy groups in the Two-degree Field Galaxy Redshift Survey: the luminous content of the groupsMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 3 2004V. R. Eke ABSTRACT The Two-degree Field Galaxy Redshift Survey (2dFGRS) Percolation-Inferred Galaxy Group (2PIGG) catalogue of ,29 000 objects is used to study the luminous content of galaxy systems of various sizes. Mock galaxy catalogues constructed from cosmological simulations are used to gauge the accuracy with which intrinsic group properties can be recovered. It is found that a Schechter function is a reasonable fit to the galaxy luminosity functions in groups of different mass in the real data, and that the characteristic luminosity L, is slightly larger for more massive groups. However, the mock data show that the shape of the recovered luminosity function is expected to differ from the true shape, and this must be allowed for when interpreting the data. Luminosity function results are presented in both the bJ and rF wavebands. The variation of the halo mass-to-light ratio, ,, with group size is studied in both of these wavebands. A robust trend of increasing , with increasing group luminosity is found in the 2PIGG data. Going from groups with bJ luminosities equal to 1010 h,2 L, to those 100 times more luminous, the typical bJ -band mass-to-light ratio increases by a factor of 5, whereas the rF -band mass-to-light ratio grows by a factor of 3.5. These trends agree well with the predictions of the simulations which also predict a minimum in the mass-to-light ratio on a scale roughly corresponding to the Local Group. The data indicate that if such a minimum exists, then it must occur at L, 1010h,2 L,, below the range accurately probed by the 2PIGG catalogue. According to the mock data, the bJ mass-to-light ratios of the largest groups are expected to be approximately 1.1 times the global value. Assuming that this correction applies to the real data, the mean bJ luminosity density of the Universe yields an estimate of ,m= 0.26 ± 0.03 (statistical error only). Various possible sources of systematic error are considered, with the conclusion that these could affect the estimate of ,m by a few tens of per cent. [source] The Arabidopsis thaliana ATP-binding cassette proteins: an emerging superfamilyPLANT CELL & ENVIRONMENT, Issue 5 2000T. G. E. Davies ABSTRACT Solute transport systems are one of the major ways in which organisms interact with their environment. Typically, transport is catalysed by integral membrane proteins, of which one of the largest groups is the ATP-binding cassette (ABC) proteins. On the basis of sequence similarities, a large family of ABC proteins has been identified in Arabidopsis. A total of 60 open reading frames (ORFs) encoding ABC proteins were identified by BLAST homology searching of the nuclear genome. These 60 putative proteins include 89 ABC domains. Based on the assignment of transmembrane domains (TMDs), at least 49 of the 60 proteins identified are ABC transporters. Of these 49 proteins, 28 are full-length ABC transporters (eight of which have been described previously), and 21 are uncharacterized half-transporters. Three of the remaining proteins identified appear to be soluble, lacking identifiable TMDs, and most likely have non-transport functions. The eight other ORFs have homology to the nucleotide-binding and transmembrane components of multi-subunit permeases. The majority of ABC proteins found in Arabidopsis can, on the basis of sequence homology, be assigned to subfamilies equivalent to those found in the yeast genome. This assignment of the Arabidopsis ABC proteins into easily recognizable subfamilies (with distinguishable subclusters) is an important first step in the elucidation of their functional role in higher plants. [source] The phosphoproteome of Fusarium graminearum at the onset of nitrogen starvationPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 1 2010Christof Rampitsch Abstract Fusarium graminearum grown under stress, such as nutrient deprivation, activates, among others, the trichothecene pathway that produces the mycotoxin deoxynivalenol and its derivatives. The kinase inhibitor staurosporine reduced the production of trichothecenes by 39% compared with control in vitro. On the other hand, phosphatase inhibitor okadaic acid increased the amount by 72% compared with the control in vitro. This suggests that phosphorylation events are involved in the signalling pathway, leading to the activation of the trichothecene pathway. Three approaches were used to study the phosphoproteome of F. graminearum under nitrogen-limiting conditions: 2-DE (2-DE: IEF×SDS-PAGE) in combination with MS protein identification; SDS-PAGE in combination with off-line IMAC and TiO2 enrichment and gel electrophoresis LC-MS analysis; and a gel-free approach using strong anion exchange chromatography, IMAC and LC-MS. A total of 348 phosphorylation sites localized in 301 peptides from 241 proteins were identified. By 2-DE, 20 phosphoproteins were identified, nine of which underwent changes during the time course examined. Using gel electrophoresis LC-MS 231 phosphopeptides were identified from three samples (ten gel slices each) at time points of nitrogen starvation t=0, 6, and 12,h. The gel-free analysis added 70 peptides from 65 proteins to the total. Proteins of unknown function and enzymes of known function comprised the largest groups overall. Ten protein kinases and seven transcription factors were identified. This is the first reported phosphoproteome of F. graminearum. [source] Immunohistochemical profile of ephrin A4 expression in human osteosarcomaAPMIS, Issue 4 2009ASMAA GABER ABDOU Ephrin receptors and ephrin ligands constitute one of the largest groups of tyrosine kinases. The division of ephrin receptors into type A or type B is determined by their ligand-binding specificities. Ephrin A4 as a ligand has a broad capacity to bind and stimulate different subtypes of ephrin A receptors. Little is known about the role of ephrins generally and ephrin A4 particularly in osteosarcoma. Ephrin A4 was immunohistochemically assessed on archival material from 46 primary osteosarcoma cases, 10 metastatic pulmonary lesions and 20 normal control bone specimens. Ephrin A4 was expressed in 100% of normal bone specimens, in 84.4% of primary osteosarcoma cases and in all metastatic pulmonary lesions. Cytoplasmic and nucleocytoplasmic patterns of ephrin A4 immunoreactivity were observed, with the predominance of the latter pattern in normal bone (100%), and in 43.5% of primary osteosarcoma cases, which showed a higher intensity of expression compared with normal bone (p<0.05). The cytoplasmic pattern is the only staining pattern seen in metastatic cases, which may suggest its role in enhancement of invasion and metastasis. The differences in the distribution of the two patterns of ephrin A4 may indicate a different biological activity of this molecule depending on its localization. The nuclear localization of ephrin A4 requires further investigation to clarify the mechanism and the significance of the nuclear trafficking of ephrin A4. [source] "Promises and Pineapples": Post-First World War Soldier Settlement at Beerburrum, Queensland, 1916-1929AUSTRALIAN JOURNAL OF POLITICS AND HISTORY, Issue 4 2005Murray Johnson Queensland's post-First World War Soldier Settlement Scheme, begun with noble and optimistic intentions in 1916, officially terminated in 1929 after ignominious failure. There were a number of factors which contributed to the erosion and ultimate destruction of this phase of land settlement, but Commonwealth-State antagonism and the incompetence of many State agricultural advisers were certainly significant elements. Beerburrum, just north of Brisbane, was one of the largest groups of settlements which characterised Queensland's attempts to turn swords into ploughshares. Beerburrum soldier settlers and their families strove valiantly to extract a basic living in the face of overwhelming adversity, and an examination of their circumstances offers a valuable window into the trials and tribulations of the entire scheme. [source] Investigation into the occupational lives of healthy older people through their use of timeAUSTRALIAN OCCUPATIONAL THERAPY JOURNAL, Issue 1 2010Rachel Chilvers Background/aim:,Older people are one of the largest groups using health-care services; therefore, it is important for occupational therapists to have an understanding of their occupational lives. Temporality is a key element of occupation, yet little research exists regarding older people and time use, despite the considerable temporal adjustments taking place at this lifestage. The aim of this study was to identify the occupational lives of healthy older people through the activities they undertake in a 24-hour period. Method:,Data analysis of time-use diaries from 90 older UK residents (aged 60,85 years) who considered themselves to be healthy was undertaken, using 15 activity codes and three pre-coded terms: necessary, enjoyable and personal. Results:,The participants spent most of their time sleeping and resting (34%), followed by performing domestic activities (13%), watching television, listening to the radio or music, or using computers (11%), eating and drinking (9%) and socialising (6%). Enjoyable activities occupied most of their time (42% of the day), followed by necessary (34%) and personal activities (16%). Conclusion:,These data contribute to the growing evidence base regarding older people as occupational beings, indicating that they are a diverse group of individuals who are meeting their needs with dynamic, positive activities. This highlights the importance of a client-centred approach to occupational therapy, as it enables the clients to have choice, control and diversity in their activities when meeting their needs. [source] | ||||||||||