Debate: Transfusing to normal hemoglobin levels improves outcome

Red cells are uniquely designed to transport oxygen and facilitate oxygen uptake by systemic tissues. Blood transfusions are thus logical therapeutic choices in patients who exhibit signs of oxygen debt. A small number of studies that have addressed patients with metabolic or physiologic signs of oxygen debt or regional ischaemia suggest that liberal blood transfusion strategies improve outcome. Therefore, armed with an understanding of the variety of clinical presentations characterising oxygen debt, as well as an appreciation of the risks involved, blood transfusions should be considered in all critically ill patients. This includes the consideration of liberalized hemoglobin triggers and hemoglobin thresholds in normal ranges

Construction public client health and safety culture in Botswana : a pilot study.

This paper presents the preliminary findings of an exploratory pilot study into the health and safety culture of a public sector client in Botswana with a view to identifying aspects to be included in a larger broad-based national survey

Designer's contribution to construction health and safety (H&S) - a case study of a public works project

Abstract: This paper presents findings from a study conducted on a public works’ construction project in Botswana to establish the contribution of designers (consultants) to construction health and safety (H&S

Client attitude to health and safety (H&S) - a report on contractor's perceptions

Abstract: The purpose of this paper is to present findings of a preliminary survey on Contractors’ perceptions of clients, attitude relative to health and safety (H&S) implementation in Botswana’s construction industry

A pilot study on public clients' contribution to construction workers' health and safety in Botswana

Abstract: This paper presents findings from a pilot study conducted in two major construction public client organisations in Botswana on their contribution to construction workers’ health and safety

A pilot study on public clients' contribution to construction workers' health and safety in Botswana

Abstract: This paper presents findings from a pilot study conducted in two major construction public client organisations in Botswana on their contribution to construction workers’ health and safety

Searching for the Rail Bonus

The inherent superiority of rail-based public transport options over bus-based alternatives, all other things being equal, has been stipulated in the literature and in the public policy discussion for some time. The exact strength of any such rail bonus is important to a public transport operator which has to consider the replacement of rail-based services by bus services. The public transport operator of the city of Dresden (DVB), while generally upgrading its services, has to consider this option, in particular where the continuing tram operation would require a costly rehabilitation of the tracks. The measurement of any such systematic preference for rail-based modes is difficult, as is requires either a before-and-after study of such a switch, controlled for the other relevant service attributes, e.g. frequency, speed, reliability, price, route, etc., or a study of a network, in which rail- and road-based modes offer comparable types of services, with bus services inparticular not restricted to feeder services to rail/tram lines. Both are rare for obvious reasons. A recent service change of the DVB offered the opportunity to look at the issue in detail. A series of surveys were undertaken for this purpose before and after: A one-day travel diary (including a household questionnaire)  A survey of the image of the services A between-mode stated preference exercise focusing on the choice between public transport and private motorised transport where public transport was provided by either bus or tram (7 choice situations) A within-mode stated preference exercise looking at the trade-offs between public transport modes, in particular levels of comfort, travel times and transfers (7 choice situations). The paper reports detailed results from this study addressing the differences in preferences between the waves (effects of familiarity with an alternative) from both separate and joint stated preference and stated preference/revealed preference models. The modelling so far indicates a consistent, but weak preference for the rail option through a higher value-of-time for rail usage, higher valuation of new rail vehicles in comparison to new busses, although they are partially balanced by a higher transfer penalty. &nbsp

Quantile regression estimands and models: revisiting the motherhood wage penalty debate

This paper discusses the crucial but sometimes neglected differences between unconditional quantile regression (UQR) models and quantile treatment effects (QTE) models. We argue that there is a frequent mismatch between the aim of the quantile regression analysis and the quantitative toolkit used in much of the applied literature, including the motherhood wage penalty literature. This mismatch may result in wrong conclusions being drawn from the data, and in the end, misguided theories. In this paper, we clarify the crucial conceptual distinction between influences on quantiles of the overall distributions, which we term population-level influences, and individual-level QTEs. Further, we use data simulations to illustrate that various classes of quantile regression models may, in some instances, give entirely different conclusions (to different questions). Finally, we compare quantile regression estimates using real data examples, showing that UQR and QTE models differ sometimes but not always. Still, the conceptual and empirical distinctions between quantile regression models underline the need to match the correct model to the specific research questions. We conclude the paper with a few practical guidelines for researchers

Order α′\alpha' heterotic domain walls with warped nearly K\"ahler geometry

We consider 1+3-dimensional domain wall solutions of heterotic supergravity on a six-dimensional warped nearly K\"ahler manifold $X_6$ in the presence of gravitational and gauge instantons of tanh-kink type as constructed in [arXiv:1109.3552]. We include first order $\alpha'$ corrections to the heterotic supergravity action, which imply a non-trivial Yang-Mills sector and Bianchi identity. We present a variety of solutions, depending on the choice of instantons, for the special case in which the SU(3) structure on $X_6$ satisfies $W_1^-=0$. The solutions preserve two real supercharges, which corresponds to $\mathcal{N}{=}1/2$ supersymmetry from the four-dimensional point of view. Besides serving as a useful framework for collecting existing solutions, the formulation in terms of dynamic SU(3) structures utilized here allows us to obtain new solutions in as yet unexplored corners of the instanton configuration space. Our approach thus offers a unified description of the embedding of tanh-kink-type instantons into half-BPS solutions of heterotic supergravity where the internal six-dimensional manifold has a warped nearly K\"ahler geometryComment: 1+27 pages, 8 figures; v2: typos corrected and minor improvements on solution cases 6-8 in section 5, published versio