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We estimate the intracluster light (ICL) component within a sample of 18 clusters detected in the XMM Cluster Survey (XCS) data using the deep (∼26.8 mag) Hyper Suprime-Cam Subaru Strategic Programme data release 1 i -band data. We apply a rest-frame μB = 25 mag arcsec−2 isophotal threshold to our clusters, below which we define light as the ICL within an aperture of R X,500 (X-ray estimate of R 500) centred on the brightest cluster galaxy (BCG). After applying careful masking and corrections for flux losses from background subtraction, we recover ∼20 per cent of the ICL flux, approximately four times our estimate of the typical background at the same isophotal level (⁠|${\sim}5{{\ \rm per\ cent}}$|⁠). We find that the ICL makes up about |${\sim}24{{\ \rm per\ cent}}$| of the total cluster stellar mass on average (∼41 per cent including the flux contained in the BCG within 50 kpc); this value is well matched with other observational studies and semi-analytic/numerical simulations, but is significantly smaller than results from recent hydrodynamical simulations (even when measured in an observationally consistent way). We find no evidence for any links between the amount of ICL flux with cluster mass, but find a growth rate of 2–4 for the ICL between 0.1 < z < 0.5. We conclude that the ICL is the dominant evolutionary component of stellar mass in clusters from z  ∼ 1. Our work highlights the need for a consistent approach when measuring ICL alongside the need for deeper imaging, in order to unambiguously measure the ICL across as broad a redshift range as possible (e.g. 10-yr stacked imaging from the Vera C. Rubin Observatory). [ABSTRACT FROM AUTHOR]

It is frequently argued that adoption of better arrangements for the employment of disabled workers has beneficial consequences for organizations. Analysis of disability statements in the annual reports of the United Kingdom highlighted the lack of attention towards effective disability management.

A method, which we have developed for determining corotation radii, has allowed us to map in detail the radial resonant structures of barred spiral galaxies. Here, we have combined this information with new determinations of the bar strength and the pitch angle of the innermost segment of the spiral arms to find relationships between these parameters of relevance to the dynamical evolution of the galaxies. We show how (1) the bar mass fraction, (2) the scaled bar angular momentum, (3) the pitch angle, and (4) the shear parameter vary along the Hubble sequence, and we also plot along the Hubble sequence (5) the scaled bar length, (6) the ratio of bar corotation radius to bar length, (7) the scaled bar pattern speed, and (8) the bar strength. It is of interest to note that the parameters (2), (5), (6), (7), and (8) all show breaks in their behaviour at type Scd. We find that bars with high shear have only small pitch angles, while bars with large pitch angles must have low shear; we also find a generally inverse trend of the pitch angle with bar strength. An inference that at first seems counter-intuitive is that the most massive bars rotate most slowly but have the largest angular momenta. Among a further set of detailed results, we pick out here the 2:1 ratio between the number of spiral arms and the number of corotations outside the bar. These results give a guideline to theories of disc–bar evolution. [ABSTRACT FROM AUTHOR]

Drawing on three longitudinal case studies involving the outsourcing of public leisure services, we explore the work transitions of staff as they transfer from one organisation to another using a three-phase analytical framework. The findings confirm the idea that outsourcing can be a difficult transition to go through, with losses occurring in relation to terms and conditions of employment. However, they also show how such changes can occur alongside the development of seemingly positive employment relationships with the new employer that challenge the view that the employment effects of public service outsourcing are invariably perceived in a negative light by employees. In doing so, the study's findings are seen to point towards the value of exploring outsourcing-related work transitions longitudinally and through the lens of the adopted analytical framework. They are also seen to have implications for how such transitions are theorised and managed, including how we might understand the nature of the employment relationship and the role of line managers. [ABSTRACT FROM AUTHOR]

We present new results on the evolution of the cosmic star formation rate as a function of stellar mass in the Subaru/XMM-Newton Deep Survey-Ultra Deep Survey field. We make use of narrow-band-selected emission line galaxies in four redshift slices between z = 1.46 and 0.63, and compute stellar masses by fitting a series of templates to recreate each galaxy's star formation history. We determine mass-binned luminosity functions in each redshift slice, and derive the star formation rate density (ρSFR) as a function of mass using the [OIII] or [OII] emission lines. We calculate dust extinction and metallicity as a function of stellar mass, and investigate the effect of these corrections on the shape of the overall ρSFR(M).We find that both these corrections are crucial for determining the shape of the ρSFR(M), and its evolution with redshift. The fully corrected ρSFR(M) is a relatively flat distribution, with the normalization moving towards lower values of ρSFR with increasing cosmic time/decreasing redshift, and requiring star formation to be truncated across all masses studied here. The peak of ρSFR(M) is found in the 1010.5 ๏ <1011.0 mass bin at z=1.46. In the lower redshift slices, the location of the peak is less certain; however, low-mass galaxies in the range 107.0 < M๏ < 108.0 play an important part in the overall ρSFR(M) out to at least z ~ 1.2. [ABSTRACT FROM AUTHOR]

This article sheds light on the role that the regulation of primarily domestic, rather than global, supply chains could play in protecting and enhancing standards of workplace health and safety, as well as employment standards more generally. The analysis presented confirms the potential relevance of such regulation in these regards. However, it also reinforces existing evidence pointing to the fact that only very rarely will market-related considerations on their own prompt purchasers to seek to directly influence the employment practices of their suppliers. The article ends therefore by highlighting a number of key issues relating to the design of regulatory initiatives aimed at protecting and enhancing employment conditions within supply chains. [ABSTRACT FROM AUTHOR]

The view that regulatory provisions protecting the employment conditions of workers need to be minimised in order to protect the business needs of employers has been an ongoing theme in British governmental policy discourse over the past three decades. For the present Coalition government, the assumption that current levels of regulation are unduly burdensome on employers and hence harmful to the economy has continued to be enthusiastically voiced, most notably in respect of the regulation of workplace health and safety. Against this backcloth, this paper develops a critical examination of the conclusions of an ‘independent’ review of health and safety regulations commissioned by the present UK Government to shed light on the way in which a deregulatory policy agenda is being furthered. The paper commences by locating the recent review of health and safety regulations, the ‘Löfstedt review’, in the context of other recent government initiatives aimed at alleviating the burden of health and safety regulation from the shoulders of employers. It then moves on to outline the nature of this review and its main conclusions and recommendations, before considering in turn its use of evidence, deployment of the notion of ‘low risk’ and lack of attention to the issue of enforcement. Finally, a concluding section draws together the key points to emerge from the preceding analysis and highlights how the Löfstedt review can be seen to form an integral part of a misleading deregulatory discourse that threatens to engender the wholesale undermining of workplace health and safety protections. [ABSTRACT FROM PUBLISHER]

This article is based on a recent study of attempts by a range of British trade unions to access and engage with Polish migrant workers at the community or labour market level, rather than workplace level. The findings suggest that migrant workers can indeed be recruited at this level. Doubts are expressed, however, about the sustainability of new membership gained in this way. These doubts are linked to a marked absence of clear union strategies to create a longer-term nexus of interest with those who are recruited, of the type advocated in, for example, the North American ‘new labor movement’ literature. This absence – it is argued – may be less a reflection of a lack of strategic leadership than a product of the difficulties unions face in identifying viable strategies relating to the representation and organization of workers above the workplace level. [ABSTRACT FROM PUBLISHER]

We present constraints on core-collapse supernova progenitors through observations of their environments within host galaxies. This is achieved through 2 routes. Firstly, we investigate the spatial correlation of supernovae with host galaxy star formation using pixel statistics. We find that the main supernova types form a sequence of increasing association to star formation. The most logical interpretation is that this implies an increasing progenitor mass sequence going from the supernova type Ia arising from the lowest mass, through the type II, type Ib, and the supernova type Ic arising from the highest mass progenitors. We find the surprising result that the supernova type IIn show a lower association to star formation than type IIPs, implying lower mass progenitors. Secondly, we use host HII region spectroscopy to investigate differences in environment metallicity between different core-collapse types. We find that supernovae of types Ibc arise in slightly higher metallicity environments than type II events. However, this difference is not significant, implying that progenitor metallicity does not play a dominant role in deciding supernova type. [ABSTRACT FROM PUBLISHER]

We have used Hα narrow-band imaging to search for star-forming satellite galaxies around 143 luminous spiral galaxies, with the goal of quantifying the frequency of occurrence of satellites resembling the Magellanic Clouds, around galaxies comparable to the Milky Way. For two-thirds of the central galaxies, no star-forming satellites are found, down to luminosities and star formation rates well below those of the Magellanic Clouds. A total of 62 satellites are found, associated with 47 of the central galaxies searched. The R-band magnitude difference between central galaxies and their satellites has a median value of 4.6 mag and a maximum value of 10.2 mag. The mean projected separation of the satellites from their central galaxies is 81 kpc, or 98 kpc for systems beyond 30 Mpc. Thus, star-forming satellites are quite rare, and the Milky Way is unusual both for the luminosity and the proximity of its two brightest satellites. We also find that the Clouds themselves are unusual in that they appear to form a bound binary pair; such close satellite pairs, of any luminosity, are also extremely rare in our survey. [ABSTRACT FROM AUTHOR]

We present a spectroscopic test confirming the potential of narrow-band optical imaging as a method for detecting star-forming satellites around nearby galaxies. To date the efficiency of such methods, and particularly the fraction of false detections resulting from its use, has not been tested. In this paper we use optical spectroscopy to verify the nature of objects that are apparently emission-line satellites, taken from imaging presented elsewhere. Observations of 12 probable satellites around 11 host galaxies are presented and used to compare the recession velocities of the host and satellite. This test confirms, in all cases, that there is a genuine line emission, that the detected line is Hα and that the satellites have similar recession velocities to their hosts with a maximum difference of ∼250 km s, consistent with their being gravitationally bound companions. We conclude that the spectroscopy has confirmed that narrow-band imaging through Hα filters is a reliable method for detecting genuine, star-forming satellites with low contamination from galaxies seen in projection along the line of sight. [ABSTRACT FROM AUTHOR]

We have used new deep observations of the Coma cluster from Galaxy Evolution Explorer to visually identify 13 star-forming galaxies with asymmetric morphologies in the ultraviolet (UV). Aided by wide-field optical broad-band and Hα imaging, we interpret the asymmetric features as being due to star formation within gas stripped from the galaxies by interaction with the cluster environment. The selected objects display a range of structures from broad fan-shaped systems of filaments and knots ('jellyfish') to narrower and smoother tails extending up to 100 kpc in length. Some of the features have been discussed previously in the literature, while others are newly identified here. We assess the ensemble properties of the sample. The candidate stripping events are located closer to the cluster centre than other star-forming galaxies; their radial distribution is more similar to that of all cluster members, dominated by passive galaxies. The fraction of blue galaxies which are undergoing stripping falls from 40 per cent in the central 500 kpc to less than 5 per cent beyond 1 Mpc. We find that tails pointing away from (i.e. galaxies moving towards) the cluster centre are strongly favoured (11/13 cases). From the small number of 'outgoing' galaxies with stripping signatures, we conclude that the stripping events occur primarily on first passage towards the cluster centre, and are short-lived compared to the cluster crossing time. Using galaxy infall trajectories extracted from a cosmological simulation, we find that the observed fraction of blue galaxies undergoing stripping can be reproduced if the events are triggered at a threshold radius of ∼1 Mpc and detectable for ∼500 Myr. Hubble Space Telescope images are available for two galaxies from our sample and reveal compact blue knots coincident with UV and Hα emission, apparently forming stars within the stripped material. Our results confirm that stripping of gas from infalling galaxies, and associated star formation in the stripped material, is a widespread phenomenon in rich clusters. Deep UV imaging of additional clusters is a promising route to constructing a statistically powerful sample of stripping events and constraining models for the truncation of star formation in clusters. [ABSTRACT FROM AUTHOR]

We produce and analyse u-band ( nm) luminosity functions (LFs) for the red and blue populations of galaxies using data from the Sloan Digital Sky Survey (SDSS) u-band Galaxy Survey ( uGS) and Deep Evolutionary Exploratory Probe 2 (DEEP2) survey. From a spectroscopic sample of 41 575 SDSS uGS galaxies and 24 561 DEEP2 galaxies, we produce colour magnitude diagrams and make use of the colour bimodality of galaxies to separate red and blue populations. LFs for eight redshift slices in the range are determined using the method and fitted with Schechter functions showing that there is significant evolution in , with a brightening of 1.4 mag for the combined population. The integration of the Schechter functions yields the evolution in the u-band luminosity density (LD) out to . By parametrizing the evolution as , we find that for the combined populations and for the blue population. By removing the contribution of the old stellar population to the u-band LD and correcting for dust attenuation, we estimate the evolution in the star formation rate (SFR) of the Universe to be . Discrepancies between our result and higher evolution rates measured using the infrared and far-UV can be reconciled by considering possibilities such as an underestimated dust correction at high redshifts or evolution in the stellar initial mass function. [ABSTRACT FROM AUTHOR]

Purpose - This paper seeks to explore the nature of the human resource reforms introduced by a French multinational into a privatized Jordanian utility and the impact of these reforms on worker experiences, attitudes and behaviour. Design/methodology/approach - The approach takes the form of a single-company case study using longitudinal interview data (44 interviews over a period of two and a half years) and a staff survey (202 completed and usable replies). Findings - Employees had experienced changes as a result of the HR reforms and these experiences were, at the aggregate level, associated with a number of positive attitudinal and behavioural outcomes. There were marked differences between different categories of staff in these respects, with more senior staff and those with higher educational qualifications being those most likely to report positive attitudinal and behavioural outcomes. Research limitations/implications - Studies of the transfer of Western management techniques to developing countries cannot treat the workforce as homogeneous. There are likely to be important differences between groups based on demographic criteria such as education, job category and length of service. However, this project used a single-company case study and so is capable of only limited generalization. Practical implications - The differences between employee groups in attitudes towards the HR reforms are best seen as the outcome of "deliberate intent" on the part of the French MNC rather than intra-organisational variations in "cultural receptivity". They indicate that, to some extent, MNCs can successfully pursue different human resource approaches in respect of different categories of staff. However, some employees felt that they were adversely affected by the reforms. Originality/value - The paper contributes an in-depth empirical study to the important but relatively under-researched area of the transfer of management techniques by MNCs to companies in developing countries. [ABSTRACT FROM AUTHOR]

This article examines the role of the Audit Commission (AC) in local government collective bargaining. While the AC has no official role in such bargaining, it has a role in monitoring the performance of local government services. In this role the AC has a clear potential, in the context of the government's 'modernization' agenda- as manifested in its 'Best Value' regime, for influencing both the content of collective agreements, and the process of collective bargaining, where these are seen to conflict with other Best Value objectives- particularly in relation to external competition. The research conducted involved a content analysis of AC inspection reports on human resource services and longitudinal case studies of two local authority union branches' experiences of Best Value and the role of the AC. The findings from the inspection reports indicate that, while the AC is actually acting to promote activities that could be seen as supportive of union bargaining agendas, notably in relation to equality type issues, they are also supporting service externalisation and thereby acting to limit the scope of their impact. The reports also indicate that, despite there being prescribed 'best practice' for local government employment relations ('social partnership' with unions), the AC is not promoting any such engagement with unions. Evidence from the case studies add weight to these observations: the AC, in one case, was deeply suspicious of an attempted union management agreement on procurement, while in the other, the AC made no criticism of the costly effects that externalization had on union-management relations. [ABSTRACT FROM AUTHOR]

A wide variety of initiatives characterized under the umbrella term of new public management have been introduced over the past two decades to improve efficiency and cost-effectiveness in the public sector. The implications of these initiatives for public sector employment relationships have been the subject of on-going debate. This article contributes to this debate through examining how employees within local authorities are managed in a time of personal crisis with a particular focus on long-term sickness absence in the context of increased management drives for efficiency under the NPM agenda. The findings reveal that for managers in two local authorities that form the focus of this study there is a tension in struggling to achieve a workable balance between the needs of employees and wider operational requirements, resulting in role ambiguity for line managers and detrimental effects for vulnerable public service workers. [ABSTRACT FROM AUTHOR]

Current cycle-network planning (CNP) at the local level tends to be dominated by a subjective-pragmatic approach in which it is only possible to consider a limited number of route alignment possibilities and development-sequencing scenarios. Although this method may produce acceptable results, it may also be true that the final design could be improved – and the construction efficiency could be enhanced – by a more comprehensive review of the available options in relation to the objectives of the intervention. Such objectives may include accident reduction, modal shift in favour of cycling, health benefits or strategic expansion of a network. This article presents work undertaken to demonstrate a holistic approach to CNP, based on a logically defined spatio-temporal model and allowing some semi-automated multiobjective optimization of network designs in a GIS-based decision-support system. The model is introduced briefly before a case study applying this model to development of a cycle network in a small town in northeast England is described. The results obtained from this case study and the implications of this research for cycle network planners are discussed. [ABSTRACT FROM AUTHOR]

This article investigates the role of ‘competition’ within Best Value (BV) and compares it with that of Compulsory Competitive Tendering (CCT). Utilising results of a survey of BV lead officers, the article reveals that ‘competition’ is not being used as widely as may have been expected. However, in terms of outcomes, services subject to BV seem to be at least as likely to be provided externally as would have been the case under CCT. Further analysis also considers the impact that party political control and service type have on the use and outcomes of competition. [ABSTRACT FROM AUTHOR]

ABSTRACT We have imaged a sample of 17 inclined spiral galaxies with measured Hα rotation curves in the K band, in order to determine the morphology of the old stellar population that dominates the mass in the disc. The K-band images of the galaxies have been used to determine the radial extent of grand-design spiral structure and compare this with the turnover radius in their rotation curves, where the rotation curve transforms from solid-body rotation to differential rotation. If the arms do not extend past this radius, the winding problem is solved. We find in all 17 cases that the arms extend past this radius, with the radius of grand-design spiral structure being a factor of 1.3–9.6 times larger than the rotation curve turnover radius. Of these galaxies, four have near neighbours and central bars and a further seven have a central bar. These bars or near neighbours may be the cause of the driving of the spiral potential in the discs of these galaxies. Of the remaining six galaxies, five show some evidence for a bar or oval distortion in their K-band images. The remaining galaxy (UGC 14) shows no evidence for a central bar and has no near neighbours. Finally, we also find that the spiral structure of these galaxies in the near-infrared is extremely regular, although some range in the regularity of spiral structure is found. To quantify this range in spiral structure, we introduce the dust-penetrated arm class, which is analogous to the dust-penetrated classification scheme of Block & Puerari and is based on the optical arm class of Elmegreen & Elmegreen. [ABSTRACT FROM AUTHOR]

Examines how human resource practitioners are responding to the British government's business case approach to promoting family-friendly policies towards a work-life balance. Overview of ethical issues entwined within the work-life balance issue; Views on the issue of work-life balance; Association between ethics, employers and work-life balance.

ABSTRACT We have imaged a sample of 20 spiral galaxies in Hα and in the near-infrared K band (2.2 μm), in order to determine the location and strength of star formation in these objects with respect to perturbations in the old stellar population. We have found that star formation rates are significantly enhanced in the vicinity of K -band arms. We have also found that this enhancement in star formation rate in arm regions correlates well with a quantity that measures the relative strengths of shocks in arms. Assuming that the K -band light is dominated by emission from the old stellar population, this shows that density waves trigger star formation in the vicinity of spiral arms. [ABSTRACT FROM AUTHOR]

Worker representation in health and safety in Britain has received statutory support since the Safety Representatives and Safety Committees Regulations 1977. Subsequent developments have, however, acted to undermine the effectiveness of these regulations. The paper consequently discusses a range of reforms that could be introduced to strengthen the present regulatory regime. [ABSTRACT FROM AUTHOR]

Examines the situation concerning safety representatives and committees within the National Health Service (NHS) in Great Britain. Statutory framework relating to trade union safety representatives; Failure of NHS employers to comply with statutory obligations; Factors affecting the adoption of Safety Representatives and Safety Committees Regulations.

Near real-time urban traffic analysis and prediction are paramount for effective intelligent transport systems. Whilst there is a plethora of research on advanced approaches to study traffic recently, only one-third of them has focused on urban arterials. A ready-to-use framework to support decision making in local traffic bureaus using largely available IoT sensors, especially CCTV, is yet to be developed. This study presents an end-to-end urban traffic volume detection and prediction framework using CCTV image series. The framework incorporates a novel Faster R-CNN to generate vehicle counts and quantify traffic conditions. Then it investigates the performance of a statistical-based model (SARIMAX), a machine learning (random forest; RF) and a deep learning (LSTM) model to predict traffic volume 30 min in the future. Tests at six locations with varying traffic conditions under different lengths of past time series are used to train the prediction models. RF and LSTM provided the most accurate predictions, with RF being faster than LSTM. The developed framework has been successfully applied to fill data gaps under adverse weather conditions when data are missing. It can be potentially implemented in near real time at any CCTV location and integrated into an online visualization platform. [ABSTRACT FROM AUTHOR]

We present an observational study of the Type IIn supernovae (SNe IIn) 2005ip and 2006jd. Broadband UV, optical, and near-IR photometry, and visual-wavelength spectroscopy of SN 2005ip complement and extend upon published observations to 6.5 years past discovery. Our observations of SN 2006jd extend from UV to mid-infrared wavelengths, and like SN 2005ip, are compared to reported X-ray measurements to understand the nature of the progenitor. Both objects display a number of similarities with the 1988Z-like subclass of SN IIn including (1) remarkably similar early- and late-phase optical spectra, (2) a variety of high-ionization coronal lines, (3) long-duration optical and near-IR emission, and (4) evidence of cold and warm dust components. However, diversity is apparent, including an unprecedented late-time r-band excess in SN 2006jd. The observed differences are attributed to differences between the mass-loss history of the progenitor stars. We conclude that the progenitor of SN 2006jd likely experienced a significant mass-loss event during its pre-SN evolution akin to the great 19th century eruption of η Carinae. Contrarily, as advocated by Smith et al., the circumstellar environment of SN 2005ip is found to be more consistent with a clumpy wind progenitor. [ABSTRACT FROM AUTHOR]