13,976 research outputs found
Becoming an HR strategic partner: tales of transition
Full text linkThis paper aims to bridge the gap between previous examinations of HR strategic partnership from a role perspective (Truss et al. 2002; Caldwell 2003) and an emerging interest in the social construction of identity (Alvesson et al. 2008). I consider ‘strategic partner’ as a local, flexible social construction framed by the broader occupational context. Based on a year-long ethnographic study, I examine the experiences of HR practitioners ‘becoming’ strategic partners, considering the themes of becoming strategic, becoming a partner and remaining a generalist. Practitioners depict becoming strategic as a ‘release’ from previous constraints, with becoming a partner positioned as filling a gap created by clients’ deficiencies in people management. Meanwhile, tensions develop as strategic partners attempt to retain a say in transactional issues. I reflect on the resulting practical issues while also considering the role of HR practitioners in “the dynamic and socially complex nature of HRM” (Francis 2003: 323)
Extracellular proton-modulated pore-blocking effects of the anticonvulsant felbamate on NMDA channel.
No full textEstuarine Muds manual
Full text linkThis report is an update of the working manual part of 'The hydraulic engineering characteristics of estuarine muds' Report No SR77, December 1986, made in the light of research conducted at Hydraulics Research Ltd (HR) and invited comments received from end users in the industry. A considerable research programme has been undertaken by HR since the publication of Report No SR77 and valuable information has been gained in respect of the behaviour of mud during tidal cycles (Ref 2), the deposition of sediment from flowing water (Ref 20), the consolidation of weak mud beds (Ref 26), the effect of sand on the consolidation and erosion processes (Ref 27) and the response of mud beds under waves (Refs 32 and 33). These findings have been incorporated into this revised manual. Report No SR77 was widely circulated to consulting engineers, contractors, academics and staff at HR, with a request for their views on the reports technical content, style and usability. Approximately half of the recipients replied with helpful and, in many cases detailed comments. Overall, the general impression was positive and encouraging. This report has been drafted with these comments taken into account wherever possible. This report summarises, in an engineering form, the main processes of cohesive sediment behaviour, namely, deposition, consolidation and erosion. The data presented are intended to show the practicing engineer which parameters are important in each of the processes and to enable broad estimates of the rates of deposition, consolidation and erosion to be made based on a limited knowledge of the field conditions. The behaviour of cohesive sediment does vary considerably in quantitative terms from one source to another. Therefore, it is crucial that the engineer appreciates that estimates based on the data presented herewith may well be in error by half an order of magnitude. For most serious engineering problems involving cohesive sediment it would be essential to undertake a detailed study. This would involve some of the following techniques: field measurements, laboratory testing of sediment, numerical modelling of hydrodynamics and sediment transport and physical modelling of hydrodynamics
Characterization of the Gating Conformational Changes in the Felbamate Binding Site in NMDA Channels
No full textAbstractThe anticonvulsant effect of felbamate (FBM) is ascribable to inhibition of N-methyl-d-aspartate (NMDA) currents. Using electrophysiological studies in rat hippocampal neurons to examine the kinetics of FBM binding to and unbinding from the NMDA channel, we show that FBM modifies NMDA channel gating via a one-to-one binding stoichiometry and has quantitatively the same enhancement effect on NMDA and glycine binding to the NMDA channel. Moreover, the binding rates of FBM to the closed and the open/desensitized NMDA channels are 187.5 and 4.6×104M−1s−1, respectively. The unbinding rates of FBM from the closed and the open/desensitized NMDA channels are ∼6.2×10−2 and ∼3.1s−1, respectively. From the binding and unbinding rate constants, apparent dissociation constants of ∼300 and ∼70μM could be calculated for FBM binding to the closed and the open/desensitized NMDA channels, respectively. The slight (approximately fourfold) difference in FBM binding affinity to the closed and to the open/desensitized NMDA channels thus is composed of much larger differences in the binding and unbinding kinetics (∼250- and ∼60-fold difference, respectively). These findings suggest that the effects of NMDA and glycine binding coalesce or are interrelated before or at the actual activation gate, and FBM binding seems to modulate NMDA channel gating at or after this coalescing point. Moreover, the entrance zone of the FBM binding site very likely undergoes a much larger conformational change along the gating process than that in the binding region(s) of the binding site. In other words, the FBM binding site becomes much more accessible to FBM with NMDA channel activation, although the spatial configurations of the binding ligand(s) for FBM themselves are not altered so much along the gating process
River regime based on sediment transport concepts
No full textRational regime relationships for the width, depth and slope of a river in equilibrium are developed using the Ackers and White sediment transport formula and the White, Paris and Bettess friction relationships, together with a principle of maximum sediment transporting capacity. This concept of maximising the sediment transporting capacity is shown to be equivalent to minimising the slope of the river. The relationships which are developed show good agreement with other empirically derived regime relationships and data from sand channels. Some comparisons are made with data from gravel rivers and the difficulties in applying regime concepts to these rivers are discussed
A New General Method for Predicting the Frictional Characteristics of Alluvial Streams
No full textA new method for predicting the frictional resistance of alluvial channels is developed using experimental data. The method is exhaustively tested on an extensive range of field and flume data and compared with the three existing methods due to Einstein and Barbarossa, Engelund and Raudkiv
Wave overtopping of seawalls, design and assessment manual
No full textThis manual draws together and summarises previous research into the overtopping performance of seawalls. Data is re-analysed to provide a set of consistent design techniques, representing the most reliable approach to the assessment of seawall overtopping by wave action. The manual consists of five principal sections. Following introductory sections 1 and 2, the third deals with the estimation of mean overtopping discharges. The fourth deals with the estimation of the number of overtopping waves and the peak individual overtopping discharges. The fifth section then examines the concept of a tolerable overtopping discharge and its potential application in design practice. The manual is intended to be used by flood and coastal defence engineers responsible for the design of new seawalls or the assessment and possible remediation of existing structures
London Gateway Port: Scheme Refinement - Port frontage - interim and final scenarios: Hydraulic studies and assessment of environmental significance
No full textHR Wallingford were commissioned by London Gateway to advise on marine and coastal processes and in particular are responsible for the modelling of the impacts of the marine works to enable an understanding of impact to be developed. They have been involved in the project since 2001. The modelling, analysis and interpretation described in this report is based on the methodologies originally employed in the hydraulic studies undertaken to support the EIA. The physical impacts of the two refined scenarios "interim" and "final" have been assessed and contrasted with the "original" scenario as assessed in the EIA. The main findings are as follows: * At an estuary wide scale, no significant changes to predictions of impact on upstream tidal propagation or extent of impact of the works as a result of scheme refinements. * Minor changes to flow regime compared to original scheme. * Siltation on Mucking Flats less than for original scheme * Maintenance (mud deposition) in the original scenario was 1.7 Mm3/year: - initial refined scenario is predicted to be 2.0 Mm3/year - final refined scenario is predicted to be 1.3 Mm3/year * In neither scenario would there need to be a change to the approach to future maintenance dredging requirements as outlined in the EIA. * Maintenance (mud deposition) at nearby berths for both refined schemes is predicted to be similar to that predicted for the original scheme. It can be inferredd from these results that if the interim scheme were modified to a scenario where three container berths had been built, there would be no further change to the flow regime at the adjacent downstream berth.London Gatewa
Meandering of small streams in Alluvium
No full textInvestigations were made at the Hydraulics Research Station of channels which achieved a meander pattern in alluvium through natural processes at discharges between 0.2 and 3.2 cusecs. These followed an earlier programme in which the behaviour of straight channels was studied. Discharge, sediment load, hydraulic gradient and channel geometry were measured, and empirical correlations of the stream geometry with discharge and sediment load were deduced. The movement of eroded bank material, the migration of meanders and the effect of sediment load on meander length were studied. It emerged that channels with small sediment loads remained straight and meandering occurred naturally at higher sediment loads. The ultimate pattern was also shown to be influenced by the initial channel condition. Flow resistance and channel shape were compared with a straight channel when about 60 percent of the energy loss was found to be due to the non-prismatic boundary of meandered channels. At the threshold of meandering, losses due to the development of shoals were found to be 25 percent of the total. Dimensional analysis elucidated that no simple relation between meander length and discharge is completely satisfactory and none of the many empirical relations between meander length and discharge has any special significance. A laboratory investigation of variable discharge hydrographs and a study of field discharge data revealed that the bank-full discharge or a flood with a recurrence interval of about a year, whichever is the lesser, generates the plan geometry
A guide to the use of grass in hydraulic engineering practice
No full textGuidance on the use of grass to stabilise surfaces subject to erosion by intermittent flow. Provides information on the erosion resistance and frictional resistance of grass. Includes recommendations on grass mixtures, etc. Extensive literature surve
- …
