979 resultados para Szymanowski, Józef, 1748-1801.


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The Ov/Br septin gene, which is also a fusion partner of MLL in acute myeloid leukaemia, is a member of a family of novel GTP binding proteins that have been implicated in cytokinesis and exocytosis. In this study, we describe the genomic and transcriptional organization of this gene, detailing seventeen exons distributed over 240 kb of sequence. Extensive database analyses identified orthologous rodent cDNAs that corresponded to new, unidentified 5' splice variants of the Ov/Br septin gene, increasing the total number of such variants to six. We report that splicing events, occurring at non-canonical sites within the body of the 3' terminal exon, remove either 1801 bp or 1849 bp of non-coding sequence and facilitate access to a secondary open reading frame of 44 amino acids maintained near the end of the 3' UTR. These events constitute a novel coding arrangement and represent the first report of such a design being implemented by a eukaryotic gene. The various Ov/Br proteins either differ minimally at their amino and carboxy termini or are equivalent to truncated versions of larger isoforms. Northern analysis with an Ov/Br septin 3' UTR probe reveals three transcripts of 4.4, 4 and 3 kb, the latter being restricted to a sub-set of the tissues tested. Investigation of the identified Ov/Br septin isoforms by RT-PCR confirms a complex transcriptional pattern, with several isoforms showing tissue-specific distribution. To date, none of the other human septins have demonstrated such transcriptional complexity.

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The work presented here is aimed at determining the potential and limitations of Raman spectroscopy for fat analysis by carrying out a systematic investigation of C-4-C-24 FAME. These provide a simple, well-characterized set of compounds in which the effect of making incremental changes can be studied over a wide range of chain lengths and degrees of unsaturation. The effect of temperature on the spectra was investigated over much larger ranges than would normally be encountered in real analytical measurements. It was found that for liquid FAME the best internal standard band was the carbonyl stretching vibration nu(C = O), whose position is affected by changes in sample chain length and physical state; in the samples studied here, it was found to lie between 1729 and 1748 cm(-1). Further, molar unsaturation could be correlated with the ratio of the nu(C = O) to either nu(C = C) or delta(H-C = ) with R-2 > 0.995. Chain length was correlated with the delta(CH2)(tw)/nu(C = O) ratio, (where "tw" indicates twisting) but separate plots for odd- and even-numbered carbon chains were necessary to obtain R-2 > 0.99 for liquid samples. Combining the odd- ani even-numbered carbon chain data in a single plot reduced the correlation to R-2 = 0.94-0.96, depending on the band ratios used. For molal unsaturation the band ratio that correlated linearly with unsaturation (R-2 > 0.99) was nu(C = C)/delta(CH2)(SC) (where "sc" indicates scissoring). Other band ratios show much more complex behavior with changes in chemical and physical structure. This complex behavior results from the fact that the bands do not arise from simple vibrations of small, discrete regions of the molecules but are due to complex motions of large sections of the FAME so that making incremental changes in structure does not necessarily lead to simple incremental changes in spectra.

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RAIRS experiments have been performed to investigate the adsorption of NO on Pt{211}. Results show that adsorption is complex and strongly temperature dependent. At 307 K, three bands are seen at saturation with frequencies of 1801, 1609, and 1576 cm(-1). However, at 120 K only two bands, at 1688 and 1620 cm(-1), are observed. To help with the assignment of these vibrational bands, DFT calculations were also performed. The calculations show that a bridged NO species, bonded to the step edge, is the most stable species on the surface and gives rise to the band observed at 1610-1620 cm(-1). The calculations also suggest that the temperature dependence of NO adsorption on Ptf{211} can be assigned to NO dissociation which occurs at room temperature but not at 120 K. In particular, the RAIRS band observed at 1801 cm(-1), which is observed on adsorption at 307 K but not at 120 K, is tentatively assigned to the formation of an O-NO complex. This species forms when a NO molecule bonds on top of an O atom, which results from the dissociation of NO on the Pt{211} surface at room temperature.

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In the popular mind, the concept of 'emigration' usually refers to people voluntarily leaving one country to go to another in search of a new and better life. It presupposes some degree of choice, although it is accepted that for many emigrants, such as those who left Ireland during the nineteenth century, there were few incentives to stay at home. Current scholarship on voluntary and forced movements of people demonstrates that the distinction between the categories of 'voluntary emigrant' and 'forced exile' is often blurred. Orm Overland's study of refugee communities in the United States highlights the fact that, although the differences between the 'emigrant' and the 'exile' may be clear in extreme cases, this is not always true, as there may be 'pressing political or economic reasons behind a decision to emigrate'. Migration scholars Jan Lucassen and Leo Lucassen also question the adequacy of conceptual models of migration based on what Lindsay Proudfoot and Dianne Hall refer to as the 'straightforward binarism between free and unfree emigration'. The questions raised by these scholars are very relevant to the study of Irish people who left their country during the second half of the nineteenth century immediately after they had been discharged from prison or from Dundrum. Their stories are discussed here against a background of substantial scholarship on emigration from Ireland and on the criminal justice system within Ireland. According to David Fitzpatrick, at least eight million men, women and children emigrated from Ireland between 1801 and 1921. This large-scale movement of people was generally characterised by the voluntary emigration of individuals who funded their own passages. However, it also included schemes of assisted emigration, funded variously by governments, landlords, the poor law authorities, earlier emigrants, and philanthropists. In addition, it included people who were transported from Ireland by means of the criminal justice system a practice that had originated in the seventeenth century. What is less well known is that after the end of transportation from Ireland to eastern Australia in 1853, to Bermuda in 1863 and to Western Australia in 1868, Irish convicts continued to be channelled towards emigration by being offered early release if they agreed to leave Ireland. These people, and especially the women among them, are the subject of this article.

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This article highlights how problems of recruitment and retention in front-line services create a particular challenge to traditional HRM models and solutions. Private day nurseries make an interesting example of the challenges facing managers in the service sector as the combination of a feminised workforce, a price-sensitive service, public-private competition and state regulation create particular difficulties. We report on a study of 33 day nurseries involving interviews with managers and employees over an eight-month period. Our findings show that childcare providers have to cope with recruitment and retention problems associated with high-end interactive service provision compounded by gender segregation and small business characteristics. Our analysis of employer and employee perspectives examines labour market issues affecting recruitment, and categorises the reasons for staff turnover into internal 'push' factors, external 'pull' factors, outside factors and functional turnover.

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Madagascan frogs of the mantellid genus Mantella have been a rich source of alkaloids derived from dietary arthropods. Two species of frogs, inhabiting swamp forest, contain a unique set of alkaloids, previously proposed, based only on GC-MS and GC-FTIR data, to represent dehydro analogues of the homopumiliotoxins. The major alkaloid of this set, alkaloid 235C (2), now has been isolated in sufficient quantities (ca. 0.3 mg) to allow determination of the structure by NMR analysis. The structure of alkaloid 235C proved to be a 7,8-dehydro-8-desmethylpumiliotoxin. A comparison is presented between the mass, infrared, and H-1 NMR spectra of 235C (2) and a synthetic dehydrohomopumiliotoxin (1), initially proposed incorrectly as the structure for 235C.