Horizontal Branch A- and B-type Stars in Globular Clusters

Globular clusters offer ideal laboratories to test the predictions of stellar evolution. When doing so with spectroscopic analyses during the 1990s, however, the parameters we derived for hot horizontal branch stars deviated systematically from theoretical predictions. The parameters of cooler, A-type horizontal branch stars, on the other hand, were consistent with evolutionary theories. In 1999, two groups independently suggested that diffusion effects might cause these deviations, which we verified subsequently. I will discuss these observations and analyses and their consequences for interpreting observations of hot horizontal branch stars.Comment: 8 pages, 1 figure, style files included, Invited Lecture at IAU Symposium 224 "The A Star Puzzle

Formal and informal systems of VET: implications for employee involvement

The age-old conundrum embodied in the skills challenge is this: if it is accepted that skills are a good thing, then why is it that the uptake of skills development practices, through, for example, training and lifelong learning agenda, are not widespread? In voluntarist Britain, policy- makers, researchers, educationalists and even practitioners have been grappling for a long time with low training participation, and the low-skills, low-wage route that British industry has adopted. Problems associated with this include claims of a productivity gap that exists between the UK and major competitors and the perpetuation of short-termism that has led to the restriction of capacity development. Scholars offering a panacea to the challenge have often called for the strengthening of institutions, usually supporting such exhortations with evidence from comparative studies that other countries are better in the regulation of both internal and external labour markets. Notwithstanding the necessity to strengthen institutions and to develop a comprehensive vocational education and training (VET) system that respects social partnership and industrial democracy and genuinely involves the employee voice, there is also a need to account for the multi-layered nature that currently exists in formal and informal guises

Construction skills development in the UK : transitioning between the formal and informal

Research reported here is part of a wider study that seeks to examine the practices involved in encouraging and enabling employers to engage with the skills development agenda. A series of exploratory interviews and ethnographic observations reveal potential disconnections between skills policies at the governmental level and what actually happens in employer practices regarding skills development. On the one hand, the formal education and training system focuses on such targets as the attainment of narrowly-defined occupational standards, levels of competence, and quantitative performance measures like completion rates. On the other hand, the socialised concept of skills development takes place informally at the workplace through on-the-job training and mentoring relationships between senior and junior employees. Both the formal and informal systems appear to co-exist alongside each other, although tensions are mounting in terms of confidence that employers and the wider industry place on the efficacy of the formal system

Coordination of infrastructure development : some international comparisons

This report presents the findings from a desktop review into how governments across a selection of countries coordinate infrastructure development by working with the industry. The selected countries included the UK (Northern Ireland was examined separately from mainland UK), Canada, Germany, Japan and South Korea. The goal is to identify alternative means of coordinating infrastructure development at the government level, with a view to assist the Institution of Civil Engineers to make the case for a more strategic approach to planning and delivery of infrastructure. The need for this report derives from growing complexity in the way infrastructure development programmes are procured, and the shifting role of government from provider of infrastructure development to enabler of the process of delivery. Thus, an opportunity arose to compare alternative arrangements of government coordination. There were similarities of political governance landscape between the investigated countries regarding strategies of infrastructure delivery. Differences exist however in the way resources are allocated and decisions made regarding infrastructure development. A potential for greater transparency and collaboration between public and private sector was identified. In Germany, for example, local governments enjoy a great deal of autonomy in defining infrastructural requirements, even though the definition of requirements has to align with high-level planning principles at the regional, national and European levels. Delivery of infrastructure development is devolved to the local governments working with a range of stakeholders from both the public and private sectors with funding provided by regional allocations. By contrast, infrastructure development is coordinated by a single high-level government department Canada, Japan and South Korea. The make-up of this department varies across the three countries, with subtle differences in the roles and responsibilities of each constituent part. Nonetheless, the benefits of such an approach include a whole-systems view in decision-making and a somewhat simpler, more transparent way of funding allocation. Furthermore, in the case of Japan and South Korea, resources can be more effectively channelled towards advancing research and development related to infrastructure development capacity and more clarity in terms of skills development. The UK, on the other hand, has a fragmented approach in addressing infrastructure development, with a continuously evolving system of government departments and agencies having some form of influence on determining infrastructural requirements. In order to redress some of the challenges with such fragmentation, the situation in Northern Ireland differs slightly with the formation of a Strategic Investment Board Limited charged with overseeing infrastructure programmes, making delivery more transparent

Spectroscopy of horizontal branch stars in NGC6752 - Anomalous results on atmospheric parameters and masses

We used the ESO VLT-FORS2 facility to collect low-resolution spectra of 51 targets distributed along the Horizontal Branch. We determined atmospheric parameters by comparison with theoretical models through standard fitting routines, and masses by basic equations. Results are in general in good agreement with previous works, although not always with theoretical expectations for cooler stars (Teff<15000 K). The calculated color excess is systematically lower than literature values, pointing towards a possible underestimation of effective temperatures. Moreover, we find two groups of stars at Teff=14000 K and at Teff=27000$ K that present anomalies with respect to the general trend and expectations. We suppose that the three peculiar bright stars at Teff=14000 K are probably affected by an enhanced stellar wind. For the eight Extreme Horizontal Branch stars at Teff=27000 K which show unusually high masses we find no plausible explanation. While most of our results agree well with the predictions of standard horizontal branch evolution, we still have problems with the low masses we derive in certain temperature ranges. We believe that Kurucz ATLAS9 LTE model atmospheres with solar-scaled abundances are probably inadequate for these temperature ranges. Concerning the group of anomalous stars at Teff=27000 K, a Kolmogorov-Smirnov test indicates that there is only an 8.4% probability that these stars are randomly drawn from the general distribution in the color-magnitude diagram. This is not conclusive but points out that these stars could be both (and independently) spectroscopically and photometrically peculiar with respect to the general Extreme Horizontal Branch population.Comment: 12 pages, 10 figures, accepted for pubblication in A&A. Replaced for typos and better LaTeX outpu

The interorganisational influences on construction skills development in the UK

The UK construction skills shortage problem is well documented. To alleviate this, there is a political shift of emphasis in the UK towards employers and employees/ learners playing a more proactive role in skills development. This research seeks to examine the mechanisms that can enable such a demand-led skills development system to materialise. A desktop review and key-stakeholder analysis were undertaken to identify who participates in skills development in the construction industry in the North East of England. Exploratory interviews adopting an interpretive approach were undertaken with a sample of the key stakeholders to examine the pluralistic nature of skills development provision and the implications for the learner negotiating this environment when trying to develop skills. The interim findings suggest that whereas organisations consider skills development to be important, specific training for “upskilling” can be difficult to recognise and even more difficult to gain funding for. The complexity and fragmentation of the existing framework consequently subjects vocational skills development to the initiative and goodwill of employers, thereby reinforcing the voluntarist nature of skills development that is typical in the UK. The findings also suggest that skills development practices, at times, occur informally at the workplace and enabled through a network of local organisations. These findings highlight a need for further investigation into the efficacy of the inter-organisational dynamics and informal practices that could potentially make a demand-led skills development system a reality

Search for vertical stratification of metals in atmospheres of blue horizontal-branch stars

The observed abundance peculiarities of many chemical species relative to the expected cluster metallicity in blue horizontal-branch (BHB) stars presumably appear as a result of atomic diffusion in the photosphere. The slow rotation (typically $v\sin{i}<$ 10 km s$^{-1}$) of BHB stars with effective temperatures $T_{\rm eff}>$ 11,500 K supports this idea since the diffusion mechanism is only effective in a stable stellar atmosphere. In this work we search for observational evidence of vertical chemical stratification in the atmospheres of six hot BHB stars: B84, B267 and B279 in M15 and WF2-2541, WF4-3085 and WF4-3485 in M13. We undertake an abundance stratification analysis of the stellar atmospheres of the aforementioned stars, based on acquired Keck HIRES spectra. We have found from our numerical simulations that three stars (B267, B279 and WF2-2541) show clear signatures of the vertical stratification of iron whose abundance increases toward the lower atmosphere, while the other two stars (B84 and WF4-3485) do not. For WF4-3085 the iron stratification results are inconclusive. B267 also shows a signature of titanium stratification. Our estimates for radial velocity, $v\sin{i}$ and overall iron, titanium and phosphorus abundances agree with previously published data for these stars after taking the measurement errors into account. The results support the hypothesis regarding the efficiency of atomic diffusion in the stellar atmospheres of BHB stars with $T_{\rm eff}>$ 11,500 K.Comment: 8 pages, 12 figures, accepted for publication in Astronomy and Astrophysic