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Selected AbstractsHuman haptoglobin structure and function , a molecular modelling studyFEBS JOURNAL, Issue 22 2008F. Polticelli Hemoglobin is the most prominent protein in blood, transporting O2 and facilitating reactive oxygen and nitrogen species detoxification. Hemoglobin metabolism leads to the release of extra-erythrocytic hemoglobin, with potentially severe consequences for health. Extra-erythrocytic hemoglobin is complexed to haptoglobin for clearance by tissue macrophages. The human gene for haptoglobin consists of three structural alleles: Hp1F, Hp1S and Hp2. The products of the Hp1F and Hp1S alleles differ by only one amino acid, whereas the Hp2 allele is the result of a fusion of the Hp1F and Hp1S alleles, is present only in humans and gives rise to a longer ,-chain. Haptoglobin consists of a dimer of ,,-chains covalently linked by a disulphide bond between the Cys15 residue of each ,-chain. However, the presence of the Hp1 and Hp2 alleles in humans gives rise to HPT1-1 dimers (covalently linked by Cys15 residues), HPT1-2 hetero-oligomers and HPT2-2 oligomers. In fact, the HPT2 variant displays two free Cys residues (Cys15 and Cys74) whose participation in intermolecular disulphide bonds gives rise to higher-order covalent multimers. Here, the complete modelling of both haptoglobin variants, together with their basic quaternary structure arrangements (i.e. HPT1 dimer and HPT2 trimer), is reported. The structural details of the models, which represent the first complete view of the molecular details of human haptoglobin variants, are discussed in relation to the known haptoglobin function(s). [source] Omnidirectional multibeam sonar monitoring: applications in fisheries scienceFISH AND FISHERIES, Issue 3 2006Patrice Brehmer Abstract Data exploitation, acquired by medium-frequency omnidirectional multibeam sonar, enables original studies in fisheries research but is seldom used despite the fact that such equipment is found on most fishing vessels and a number of research vessels. This is the only system for real-time monitoring of fish schools within a horizontal omnidirectional plane about a vessel or a buoy. Between 1996 and 2001, we used two standard omnidirectional sonars and developed new methodologies for exploiting their specific acoustic data according to two main sampling schemes: ,prospecting', including fishing and searching operations, and ,drifting', as with an instrumental buoy system or aboard a stationary vessel. We present a complete method for continuous data acquisition from aboard a research vessel or commercial boat, with automated data extraction by picture analysis and a data processing method. Two cases of data analysis are considered: the first on a school-by-school basis, the ,single school' mode; the second taking into account all fish schools detected within the sonar sampling volume, the ,cluster' mode. Elementary sonar information is divided into five categories that comprise 24 survey and sonar parameters and 55 school, cluster and fisher behaviour descriptors. We review the applications of these categories and discuss perspectives for their use in fisheries science. If the sonar system enables the evaluation of the effects of vessel avoidance on fish school biomass assessment, no accurate abundance estimate can be provided by a simple sonar echo-integration process. Omnidirectional sonar data can be used to analyse collectively the fish schools' swimming speed, kinematics in terms of diffusion and migration, aggregative dynamics as school splitting and merging indexes, spatial characteristics of clusters such as school density, 2D structure and fisher behaviour. The prospect of integrating such data into a fish school database, including multifrequency echo-sounder and lateral multibeam (3D) sonar data combined with a species recognition method, will enable a complete view of fish school behaviour and consequently the adoption of accurate fisheries management methods. [source] Attacking Poverty,a strategic dilemma for the World BankJOURNAL OF INTERNATIONAL DEVELOPMENT, Issue 3 2001Michael Hubbard Attacking Poverty has attracted more than the usual interest in World Development Reports mainly because it reflects the dilemma in future strategy for the World Bank. Its basis in a widely welcomed consultation with the poor, its transparent process and new conceptual framework contrast with limited development of the new themes , equality, security, empowerment of the poor , and of issues to do with aid: resources and rights. Contributors to this special issue discuss the dilemma reflected in Attacking Poverty from a number of angles: critical self-awareness by World Bank, promoting equality, shifting from the Washington Consensus, limits to the Bank's role, and enabling collective action by the poor. Other contributions discuss how the analysis in Attacking Poverty should be strengthened: inclusion of urban poverty and urbanisation's role in political development, promoting informal means of reducing vulnerability, and investigation of the long term consequences of the HIV/AIDS pandemic. Priorities for the next poverty-focused World Development Report (2010?) should include a more disaggregated and complete view of who is poor, why and where, and analysis of progress in political development. The World Bank may be best able to contribute to political development by extending to the subnational and public services level its main achievement of recent decades: the gathering, analysis and dissemination of comparative development data, to help move the focus of politics towards improving services and living standards. Copyright © 2001 John Wiley & Sons, Ltd. [source] Shared governance as vertical alignment of nursing group power and nurse practice council effectivenessJOURNAL OF NURSING MANAGEMENT, Issue 1 2009RICHARD J. BOGUE PhD Aim(s), This study validates an instrument for measuring the effectiveness of nursing practice councils and offers a framework for measuring and understanding shared governance. Background, Empowerment results from the vertical alignment of nursing group power with nursing unit power practices. The field lacks an instrument for measuring nurses' practice of power. Method(s), Two studies (n1 = 119; n2 = 248) are used to validate the Nursing Practice Council effectiveness scale (NPCes). Results, NPCes is a valid and reliable index of nursing practice council effectiveness. This study suggests specific diagnostic tools to understand two levels for actualized power, one at the group or departmental level and one at the unit level. Conclusion(s), NPCes and the Sieloff-King Assessment of Group Power within Organizations (SKAGPO) can be used together to improve examination of shared governance. Examining group power as well as unit-level practices may give a more complete view of barriers to nurse empowerment. Implications for nursing management, Changing nursing power and practices in an organization may be made more effective by engaging and monitoring vertical alignment of strategies fostering power competencies among nurse leaders and simultaneously supporting nursing practice councils as a means of exercising nurse authority at the unit level. [source] The Millennium Galaxy Catalogue: a census of local compact galaxiesMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2006J. Liske ABSTRACT We use the Millennium Galaxy Catalogue (MGC) to study the effect of compact galaxies on the local field galaxy luminosity function (LF). Here, we observationally define as ,compact' galaxies that are too small to be reliably distinguished from stars using a standard star,galaxy separation technique. In particular, we estimate the fraction of galaxies that are misclassified as stars due to their compactness. We have spectroscopically identified all objects to Bmgc= 20 mag in a 1.14-deg2 subregion of the MGC, regardless of morphology. From these data we develop a model of the high surface brightness (SB) incompleteness and estimate that ,1 per cent of galaxies with Bmgc < 20 mag are misclassified as stars, with an upper limit of 2.3 per cent at 95 per cent confidence. However, since the missing galaxies are preferentially sub- L* their effect on the faint end of the LF is substantially amplified: we find that they contribute ,6 per cent to the total LF in the range ,17 < MB < ,14 mag, which raises the faint end slope , by 0.03+0.02,0.01. Their contribution to the total B -band luminosity density is ,2 per cent. Roughly half of the missing galaxies have already been recovered through spectroscopy of morphologically stellar targets selected mainly by colour. We find that the missing galaxies mostly consist of intrinsically small, blue, star forming, sub- L* objects. In combination with the recent results of Driver et al. we have now demonstrated that the MGC is free from both high- and low-SB selection bias for giant galaxies (MB,,17 mag). Dwarf galaxies, on the other hand, are significantly affected by these selection effects. To gain a complete view of the dwarf population will require both deeper and higher-resolution surveys. [source] A study of departures from the inverse-barometer response of sea level to air-pressure forcing at a period of 5 daysTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 597 2004E. L. Mathers Abstract The response of the sea level to atmospheric forcing is investigated through the cross-spectral analysis of tide-gauge data from around 100 island and deep-ocean stations and atmospheric pressure records. The focus is at a period of 5 days, coinciding with an atmospheric pressure oscillation (Madden,Julian wave) of the same frequency. Outside the Tropics the energy in synoptic weather systems masks the small amplitude of the pressure wave, resulting in a response indistinguishable from that of an inverse barometer (IB). Within the Tropics, variability of air pressure is smaller in comparison with the amplitude of the pressure wave and departures from the IB model are found. Analysis of several sub-surface pressure records in the tropical Atlantic also yields departures at this time-scale, and indicates the barotropic nature of the response. Findings from a near-global barotropic numerical model forced with realistic air pressure and wind-stress fields show reasonable agreement with results at tide-gauge locations, and provide a more complete view of the sea-level response. These results indicate the possibility of providing an improved simulation of sea-level response to atmospheric-pressure forcing at this time-scale than is currently provided by the IB model, for example in the field of satellite altimetry. Copyright © 2004 Royal Meteorological Society [source] | ||||||||||