A Northern Snowmelt Model

In early 1968, a large petroleum discovery was made in the Prudhoe Bay area of Alaska's Arctic Coastal Plain. This discovery has led Alaska into a period of development of unprecedented speed and magnitude. This development will require the construction of many engineering facilities which are affected by the water resources. The design of each of these requires an understanding of the hydrologic system, a system which is dominated in Alaska by low temperatures, high latitudes, large elevation differences and sparse data. The latter factor is unique to Alaska and makes application of common design techniques virtually impossible

High-temperature environments of human evolution in East Africa based on bond ordering in paleosol carbonates

Many important hominid-bearing fossil localities in East Africa are in regions that are extremely hot and dry. Although humans are well adapted to such conditions, it has been inferred that East African environments were cooler or more wooded during the Pliocene and Pleistocene when this region was a central stage of human evolution. Here we show that the Turkana Basin, Kenya—today one of the hottest places on Earth—has been continually hot during the past 4 million years. The distribution of ^(13)C-^(18)O bonds in paleosol carbonates indicates that soil temperatures during periods of carbonate formation were typically above 30 °C and often in excess of 35 °C. Similar soil temperatures are observed today in the Turkana Basin and reflect high air temperatures combined with solar heating of the soil surface. These results are specific to periods of soil carbonate formation, and we suggest that such periods composed a large fraction of integrated time in the Turkana Basin. If correct, this interpretation has implications for human thermophysiology and implies a long-standing human association with marginal environments

Mathematical modelling of nanoparticle delivery to vascular tumours

This paper was presented at the 2nd Micro and Nano Flows Conference (MNF2009), which was held at Brunel University, West London, UK. The conference was organised by Brunel University and supported by the Institution of Mechanical Engineers, IPEM, the Italian Union of Thermofluid dynamics, the Process Intensification Network, HEXAG - the Heat Exchange Action Group and the Institute of Mathematics and its Applications.The goal of any cancer therapy is to achieve efficient, tissue-specific targeting of drugs to cancer cells. However, most anticancer agents act on healthy and malignant tissue alike, potentially resulting in side effects to healthy tissue. This has motivated the development of treatment strategies that are cancer-cell specific; one approach uses biomimetic polymer vesicles (BPV) to deliver chemotherapeutic drugs into cells before releasing them. BPVs are synthetic membrane enclosed, nanometre-sized structures, and provide ideal drug delivery vectors because specific targeting to cancer cells can be achieved by coating with tumourspecific molecules. We present several mathematical models covering a wide range of length-scales pertinent to BPV-mediated delivery protocols and focus on capturing the in vivo environment by evaluating the impact of the underlying vascular structure upon the governing transport mechanisms. Firstly, we present models of specific binding of BPVs to cancer cells. Subsequently we examine the implications of these model outputs in the contexts of both discrete capillary architectures and higher level homogenized-models that track blood and BPV transport at the tissue scale (both intra- and extra-tumorally). Numerical solutions are discussed, and recommendations are presented on that optimal integration of the models to generate quantitative predictions associated with BPV treatment efficacy

Subduction Duration and Slab Dip

The dip angles of slabs are among the clearest characteristics of subduction zones, but the factors that control them remain obscure. Here, slab dip angles and subduction parameters, including subduction duration, the nature of the overriding plate, slab age, and convergence rate, are determined for 153 transects along subduction zones for the present day. We present a comprehensive tabulation of subduction duration based on isotopic ages of arc initiation and stratigraphic, structural, plate tectonic and seismic indicators of subduction initiation. We present two ages for subduction zones, a long‐term age and a reinitiation age. Using cross correlation and multivariate regression, we find that (1) subduction duration is the primary parameter controlling slab dips with slabs tending to have shallower dips at subduction zones that have been in existence longer; (2) the long‐term age of subduction duration better explains variation of shallow dip than reinitiation age; (3) overriding plate nature could influence shallow dip angle, where slabs below continents tend to have shallower dips; (4) slab age contributes to slab dip, with younger slabs having steeper shallow dips; and (5) the relations between slab dip and subduction parameters are depth dependent, where the ability of subduction duration and overriding plate nature to explain observed variation decreases with depth. The analysis emphasizes the importance of subduction history and the long‐term regional state of a subduction zone in determining slab dip and is consistent with mechanical models of subduction

Parenteral antibiotics at home

Giving parenteral antibiotics to patients at home compared to in hospital presents unique challenges

Effect of age and gender on sweat lactate and ammonia concentrations during exercise in the heat

The dependence of sweat composition and acidity on sweating rate (SR) suggests that the lower SR in children compared to adults may be accompanied by a higher level of sweat lactate (Lac-) and ammonia (NH3) and a lower sweat pH. Four groups (15 girls, 18 boys, 8 women, 8 men) cycled in the heat (42ºC, 20% relative humidity) at 50% VO2max for two 20-min bouts with a 10-min rest before bout 1 and between bouts. Sweat was collected into plastic bags attached to the subject's lower back. During bout 1, sweat from girls and boys had higher Lac- concentrations (23.6 ± 1.2 and 21.2 ± 1.7 mM; P 0.05; r = -0.27). Sweat Lac- concentration dropped during exercise bout 2, reaching similar levels among all groups (overall mean = 13.7 ± 0.4 mM). Children had a higher sweat NH3 than adults during bout 1 (girls = 4.2 ± 0.4, boys = 4.6 ± 0.6, women = 2.7 ± 0.2, and men = 3.0 ± 0.2 mM; P < 0.05). This difference persisted through bout 2 only in females. On average, children's sweat pH was lower than that of adults (mean ± SEM, girls = 5.4 ± 0.2, boys = 5.0 ± 0.1, women = 6.2 ± 0.5, and men = 6.2 ± 0.4 for bout 1, and girls = 5.4 ± 0.2, boys = 6.5 ± 0.5, women = 5.2 ± 0.2, and men = 6.9 ± 0.4 for bout 2). This may have favored NH3 transport from plasma to sweat as accounted for by a significant correlation between sweat NH3 and H+ (r = 0.56). Blood pH increased from rest (mean ± SEM; 7.3 ± 0.02) to the end of exercise (7.4 ± 0.01) without differences among groups. These results, however, are representative of sweat induced by moderate exercise in the absence of acidosis

Patient choice at the point of GP referral: Department of Health

1 The Department of Health has a Public Service Agreement target to ensure that by the end of 2005 every hospital appointment in the National Health Service in England (the NHS) will be booked for the convenience of the patient, making it easier for patients and their General Practitioners (GPs) to choose the hospital and consultant that best meets their need. The Department aims to provide patients with the opportunity to choose between four to five healthcare providers for elective hospital treatment by December 2005. In consultation with their GP, patients should be able to choose, from a menu of NHS and independent sector healthcare providers, their preferred location for treatment. Patients should also be able to book the time and date of their initial outpatient appointment within 24 hours of the decision to refer the patient for treatment. This target will apply to around 9.4 million patients referred for hospital treatment by their GP each year, around four per cent of the total estimated 241 million GP consultations. 2 Choice at referral can contribute to a more patientfocused health service, bringing benefits to both patients and the NHS. But providing such a choice will not happen by accident. There are a number of dependencies and interactions with other policies that need to be managed. Information Technology (IT) systems need to be developed and modified and significant cultural, organisational and behavioural changes will need to be made by patients, NHS organisations and staff. 3 This report examines whether the Department is on track to deliver choice at the point of referral successfully by the target date of December 2005. Our work has found that: a Progress has been made towards delivering choice at referral through establishing the required organisational infrastructure, commissioning new IT systems and modifications to existing ones, and providing support for the NHS organisations that will deliver it. b The engagement of GPs is currently low and is a key risk which the Department must address to deliver choice successfully. The Department plans to address this risk through a campaign to inform and engage GPs during 2005 and it will need to monitor carefully the progress of this campaign. c Choice at referral will be delivered most efficiently and effectively through electronic booking (e-booking, also known as Choose and Book), in which the Electronic Booking Service, commissioned by the Department’s National Programme for IT (NPfIT), is linked to upgraded or new computer systems in hospitals and GPs’ surgeries. However, e-booking will not be universally available by December 2005. Until e-booking is fully adopted choice will have to be provided in other, less efficient, ways. d Parts of the NHS still have much to do if they are to deliver choice. A significant minority of Primary Care Trusts do not yet have adequate plans in place to manage the introduction of choice and some may struggle to manage the required new commissioning arrangements. 4 Our more detailed findings are as follows. Progress has been made towards delivering choice at referral 5 The Department believes that choice is affordable. Additional annual infrastructure and transaction costs are estimated to be £122 million – or 1.4 per cent of the current total expenditure on elective care. The main aim of introducing choice is to improve services for patients, but it should lead to increased efficiencies in primary and secondary care services worth an estimated £71 million, off-setting some of these costs. 6 It is essential that choice is supported by other elements of system reform including e-booking, payment by results, commissioning and appropriate capacity. Modelling exercises have shown that the system reforms should work in harmony with one another. Payment by results should enable the transfer of funding to follow the patient and there should be sufficient capacity across the system to enable choice to be effective. 7 Much of the organisational infrastructure that is required for choice is in place and there is clear accountability for the delivery of the programme. To strengthen detailed national programme management arrangements the Department created, on 22 December 2004, a new post of National Implementation Director for Choose and Book, with effect from 10 January 2005. The new Director will be responsible for overseeing the implementation of choice within the NHS whilst the National Programme for IT Group Programme Director for Choose and Book will continue to be responsible for Choose and Book technology development and deployment, patient access and Choose and Book contract management. 8 The Department has provided different types of support to the NHS – for example, ten pilot schemes have been run to test the policy in practice. It has set up a system for periodically measuring progress and used this to establish the position at the end of October 2004, creating a baseline against which to monitor future progress. 9 Research has identified what information patients will want to base their choices on, and the Department is seeking to provide this. While it is unlikely that full information will be available for December 2005, the majority of those aspects identified by patients as being the most important, such as waiting times and basic access information, will be in place. The Department plans to increase the information available over time. The key risk to the delivery of choice is the engagement of GPs 10 Choice cannot be delivered without support from GPs but our survey of GPs found that around half of GPs know very little about it and 61 per cent feel either very negative or a little negative. GPs’ concerns include practice capacity, workload, consultation length and fears that existing health inequalities will be exacerbated. The Department has deliberately held back its main effort to inform and engage GPs about choice until it has had a working e-booking system to show GPs, but it intends to mount a campaign to inform and engage GPs during 2005. Until e-booking is fully adopted choice will be supported by other mechanisms 11 The Department has commissioned Atos Origin to develop a national system for e-booking, which will be linked to upgraded or new Patient Administration Systems in hospitals and IT systems in GPs’ surgeries to provide an overall service known as e-booking. The National Programme for IT has planned the roll out of e-booking on an incremental basis to minimise risk, and to link it by the end of 2005 to some 60 to 70 per cent of hospital systems and GP practices. 12 E-booking is the most effective and efficient way of delivering the Department’s plans for choice, and alternative booking mechanisms offer poorer value for money. Atos Origin has delivered a functioning system and the first booking using e-booking was made in July 2004. However the roll-out of e-booking has been slower than planned and at the end of December 2004 only 63 bookings had been made. Problems have included the reluctance of users to work with an unreliable end-to-end system, limited progress in linking to GP and hospital systems, and the limited number of GPs willing to use the system. 13 The Department believes that new releases of software have addressed the reliability of the whole end-to-end system and that having a fully operational system will encourage GPs to engage with e-booking. The roll-out of changes to hospital systems to allow them to link to e-booking is gathering pace and four types of GP systems can now link to e-booking, although the largest supplier has not yet agreed an implementation plan. A combined team of Departmental and NHS personnel are working with the three main existing GP system suppliers to agree a national deployment schedule. This work should be completed by February 2005, along with a nationally negotiated commercial arrangement. The Department is also developing and trialling contingency plans against further delays, as well as alternatives to the fully integrated Choose and Book solution. Parts of the NHS still have much to do 14 Programme management arrangements in the NHS are incomplete. While most Primary Care Trusts expect to be able to deliver the choice target, there is variability in their overall performance. As many as a quarter of Primary Care Trusts currently forecast that they will not deliver the choice targets. In addition, some Primary Care Trusts may struggle to manage the new commissioning arrangements and two-thirds have yet to commission the required number of providers. The department is developing a framework of support to assist trusts to overcome these obstacles. 15 The Department needs urgently to address the low level of GP support for their plans for implementing choice at referral, and should: I Press on urgently with its plans for informing GPs about the implementation of choice at referral and its impact on GPs and patients. II Monitor the views of GPs, for example by a regular survey, repeating key questions from our own survey, to assess the rate of progress being achieved towards the level of support needed to meet its target of full implementation by December 2005. III Consider whether further action is needed to secure the required level of GP support, once GPs are fully informed on what choice at referral involves. 16 The Department should also: IV Complete its planned benefits realisation plan for choice at referral by the summer of 2005, along with a monitoring mechanism and quantified targets. V Keep under regular and close review the progress of its planned implementation of choice through implementing e-booking and consider the scope for accelerating the roll-out of e-booking to make it available everywhere by December 2005. VI If it becomes clear that it is not possible to deliver e-booking everywhere by December 2005, the Department should: a monitor closely the development of the interim solutions to ensure that they meet their delivery dates; and b ensure that the implementation of interim solutions does not detract from the priority of bringing in fully integrated e-booking systems as soon as possible. VII Establish an evaluation framework for Primary Care Trust commissioning to assist Strategic Health Authorities in assessing the capacity and skills of Primary Care Trusts in this area and securing improvements in capacity and skills where necessary

An olfactory subsystem that detects carbon disulfide and mediates food-related social learning

In mammals, pheromones and other social cues can promote mating or aggression behaviors; can communicate information about social hierarchies, genetic identity and health status; and can contribute to associative learning. However, the molecular, cellular, and neural mechanisms underlying many olfactory-mediated social interactions remain poorly understood. Here, we show a specialized olfactory subsystem that includes olfactory sensory neurons (OSNs) expressing the receptor guanylyl cyclase GC-D, the cyclic nucleotide-gated channel subunit CNGA3, and the carbonic anhydrase isoform CAII (GC-D(+) OSNs) is required for the acquisition of socially transmitted food preferences (STFPs) in mice

Researching the Aftermath of Slavery in Mainland East Africa: Methodological, Ethical, and Practical Challenges

This article examines ethical, practical, and methodological challenges in researching the aftermath of slavery in continental East Africa away from the coastal plantation belt. Interest in post-slavery there is recent and inspired by the apparent contrast with West Africa, where the issue is much more salient. The article explains this silence by highlighting politically-motivated avoidance of the issue in colonial sources and the preference of post-colonial historians for ‘useful’ pasts. Further, it questions the balance of successful integration and continuing marginalization reflected in the apparent obsolescence of slavery. It argues that tracing the trajectories of ex-slaves requires attention to all forms of social inequality and dependency, to the potential status implications for informants of speaking about slavery, and to the variety of terms and fields of meaning relevant to freedom, unfreedom and dependency. Recent research in this vein shows that slave antecedents remain a matter of aibu, shame, and that ex-slaves’ disappearance as a social category took lifelong efforts on their part. While the social valence of slave antecedents is relatively limited in mainland East Africa, slavery remains a problematic and painful heritage that demands great circumspection by researchers

Three-year Trajectories of Global Perceived Quality of Life for Youth With Chronic Health Conditions

Purpose Objectives of this longitudinal study were to examine 3-year trajectories of global perceived quality of life (QOL) for youth with chronic health conditions, as obtained from youth and parent reports, and to identify personal and environmental factors associated with the trajectory groups for each perspective. Methods Youth with various chronic conditions aged 11–17 years and one of their parents were recruited from eight children’s treatment centers. Latent class growth analysis was used to investigate perceived QOL trajectories (separately for youth and parent perspectives) over a 3-year period (four data collection time points spaced 12 months apart). Multinomial logistic regression was employed to identify factors associated with these trajectories. Results A total of 439 youth and one of their parents participated at baseline, and 302 (69 %) of those youth/parent dyads completed all four data collection time points. Two QOL trajectories were identified for the youth analysis: ‘high and stable’ (85.7 %) and ‘moderate/low and stable’ (14.3 %), while three trajectories were found for the parent analysis: ‘high and stable’ (35.7 %), ‘moderate and stable’ (46.6 %), and ‘moderate/low and stable’ (17.7 %). Relative to the ‘high and stable’ groups, youth with more reported pain/other physical symptoms, emotional symptoms, and home/community barriers were more likely to be in the ‘moderate and stable’ or ‘moderate/low and stable’ groups. Also, youth with higher reported self-determination, spirituality, family social support, family functioning, school productivity/engagement, and school belongingness/safety were less likely to be in the ‘moderate and stable’ or ‘moderate/low and stable’ groups, compared to the ‘high and stable’ groups. Conclusion Findings suggest that youth with chronic conditions experience stable global perceived QOL across time, but that some individuals maintain stability at moderate to moderate/low levels which is related to ongoing personal and environmental influences. Potential benefits of universal strategies and programs to safeguard resilience for all youth and targeted interventions to optimize certain youths’ global perceived QOL are indicated