We describe elongate, wet, subglacial bedforms in the shear margins of the NE Greenland Ice Stream and place some constraints on their formation. Lateral shear margin moraines have been observed across the previously glaciated landscape, but little is known about the ice-flow conditions necessary to form these bedforms. Here we describe in situ sediment bedforms under the NE Greenland Ice Stream shear margins that are observed in active-source seismic and ground-penetrating radar surveys. We find bedforms in the shear margins that are ~500 m wide, ~50 m tall, and elongated nearly parallel to ice-flow, including what we believe to be the first subglacial observation of a shear margin moraine. Acoustic impedance analysis of the bedforms shows that they are composed of unconsolidated, deformable, water-saturated till. We use these geophysical observations to place constraints on the possible formation mechanism of these subglacial features.

For artificial agents trading off exploration (food seeking) versus (short-term) exploitation (or consumption), our experiments suggest that uncertainty (interpreted information, theoretically) magnifies food seeking. In more uncertain environments, with food distributed uniformly randomly, exploration appears to be beneficial. In contrast, in biassed (less uncertain) environments, with food concentrated in only one part, exploitation appears to be more advantageous. Agents also appear to do better in biassed environments.

Following pioneering work in Norway, cirque glaciers have widely been viewed as rigidly rotating bodies. This model is incorrect for basin-filling cirque glaciers, as we have demonstrated at West Washmawapta Glacier, a small glacier in the Canadian Rocky Mountains. Here we report observations at the same glacier that assess whether complex temporal variations of flow also occur. For parts of three summers, we measured daily displacements of the glacier surface. In one year, four short-duration speed-up events were recorded. Three of the events occurred during the intervals of warmest weather, when melt was most rapid; the fourth event occurred immediately following heavy rain. We interpret the speed-up events as manifestations of enhanced water inputs to the glacier bed and associated slip lubrication by increased water volumes and pressures. No further speed-ups occurred in the final month of the melt season, despite warm temperatures and several rainstorms; the dominant subglacial water system likely transformed from one of poorly connected cavities to one with an efficient channel network. The seasonal evolution of hydrology and flow resembles behaviors documented at other, larger temperate glaciers and indicates that analyses of cirque erosion cannot rely on simple assumptions about ice dynamics.

Introduction: Intravenous (IV) cannulation is commonly performed in emergency departments (ED), often causing substantial pain and distress. Distraction has been shown to reduce child-reported pain, but there is currently little published about the effects of using iPad technology as a distraction tool. Our primary objective was to compare the reduction of pain and distress using iPad distraction (games, movies, books of the child’s choice) in addition to standard care, versus standard care alone. Methods: This randomized clinical trial, conducted at the Stollery Childrens Hospital ED, recruited children between ages 6 to 11 years requiring IV cannulation. Study arm assignment was performed using REDCaps randomization feature. Due to the nature of the intervention, blinding was not possible for the children, parents or research and ED staff, but the data analyst was blinded to intervention assignment until completion of analysis. Pain, distress, and parental anxiety were measured using the Faces Pain Scale-Revised, the Observed Scale of Behavioural Distress-Revised, and the State Trait Anxiety Inventory, respectively. The pain scores and observed behavioural distress scores were compared using the Mann-Whitney U test. Other co-variates were analyzed using a linear regression analysis. Results: A total of 85 children were enrolled, with 42 receiving iPad distraction and 43 standard care, of which 40 (95%) and 35 (81%) children received topical anesthesia, respectively (p=0.09). There were 40 girls (47.1%) with a mean age of 8.32 +/− 1.61 years. The pain scores during IV cannulation (p=0.35) and the change in pain score during the procedure compared to baseline (p=0.79) were not significantly different between the groups, nor were the observed distress scores during IV cannulation (p=0.09), or the change in observed distress during the procedure compared to baseline (p=0.44). A regression analysis showed children in both groups had greater total behavioural stress if it was their first ED visit (p=0.01), had prior hospitalization experience (p=0.04) or were admitted to hospital during this visit (p=0.007). A previous ED visit, however, was predictive of a greater increase in parental anxiety from baseline (p=0.02). When parents were asked whether they would use the same methods to manage pain for their child, parents of the iPad group were more likely to say yes than were parents of the standard care group (p=0.03). Conclusion: iPad distraction during IV cannulation in school-aged children was not found to decrease pain or distress more than standard care alone, but parents preferred its use. The effects of iPad distraction may have been over-shadowed by potent topical anesthetic effect. Future directions include exploring iPad distraction for other age groups, and studying novel technology such as virtual reality and interactive humanoid robots.

To investigate the subsurface hydrological characteristics of an overdeepened cirque glacier, nine boreholes were drilled to the bed of West Washmawapta Glacier, British Columbia, Canada, in summer 2007. All holes were surveyed with a video camera, and four were subsequently instrumented with a combination of pressure transducers, thermistors and conductivity sensors. Diurnal pressure and temperature records indicate the presence of a hydraulically connected subglacial drainage system towards the northern glacier margin. Hydraulic jacking in the overdeepening, controlled by changing water volume in the marginal zone, potentially impacts basal ice flow and erosion. The presence of a sediment layer underlying the glacier also likely impacts hydrology and ice dynamics. Influx of warm groundwater into the basal system raises subglacial water temperatures above the pressure-melting point (pmp) and induces diurnal water temperature fluctuations of as much as 0.8°C; water temperatures above the pmp could affect basal melt rates and the development of subglacial drainage systems. These observations suggest that the characteristics of the subglacial drainage system substantially affect patterns of flow and erosion by this small cirque glacier.

Borehole instrument records from a cirque glacier with an overdeepened bed are examined to assess the validity of widely held glacial hydrological assumptions. At this glacier, hydraulic-potential calculations suggest water below overburden pressure will flow into the overdeepening, where the steepness of the riegel causes water to pool in the basin and increase in pressure. Our subglacial water pressure data also show high consistent pressures in the overdeepening and the presence of an active, variable-pressure drainage system towards the margin of the cirque. Therefore, we find that although uniform hydraulic-potential calculations are not directly applicable, they can still be useful for interpretation of the subglacial hydrological system. We also examine supercooling assumptions under different pressure and temperature regimes for water flowing over a riegel, driven using our borehole records of subglacial water temperatures that are consistently above the pressure-melting point during the late melt season. Our results show that even a slight increase in basal temperatures relative to the local pressure-melting point is sufficient to prevent a reduction in basal hydraulic conductivity as a result of supercooling freeze-on.

Introduction: This paper is a report of a qualitative study of emergency and critical care nurses' perceptions of occupational response and preparedness during infectious respiratory disease outbreaks including severe acute respiratory syndrome (SARS) and influenza.

Problem: Healthcare workers, predominantly female, face occupational and personal challenges in their roles as first responders/first receivers. Exposure to SARS or other respiratory pathogens during pregnancy represents additional occupational risk for healthcare workers.

Methods: Perceptions of occupational reproductive risk during response to infectious respiratory disease outbreaks were assessed qualitatively by five focus groups comprised of 100 Canadian nurses conducted between 2005 and 2006.

Results: Occupational health and safety issues anticipated by Canadian nurses for future infectious respiratory disease outbreaks were grouped into four major themes: (1) apprehension about occupational risks to pregnant nurses; (2) unknown pregnancy risks of anti-infective therapy/prophylaxis; (3) occupational risk communication for pregnant nurses; and (4) human resource strategies required for pregnant nurses during outbreaks. The reproductive risk perceptions voiced by Canadian nurses generally were consistent with reported case reports of pregnant women infected with SARS or emerging influenza strains. Nurses' fears of fertility risks posed by exposure to infectious agents or anti-infective therapy and prophylaxis are not well supported by the literature, with the former not biologically plausible and the latter lacking sufficient data.

Conclusions: Reproductive risk assessments should be performed for each infectious respiratory disease outbreak to provide female healthcare workers and in particular pregnant women with guidelines regarding infection control and use of anti-infective therapy and prophylaxis.

Jones uses a mechanism from the linguistic theory, Optimality Theory, to generate the range of kin systems observed in human cultures and human languages. The observed distribution of kinship systems across human societies suggests that some possibilities are preferred over others, a result that would indicate Jones' model needs to be refined, especially in its treatment of markedness.

L-tryptophan 50 mg/kg was administered orally to patients suffering from either unipolar or bipolar affective illness, and the concentration of 5-hydroxyindol-acetic acid estimated in their cerebrospinal fluid eight hours later. There was no significant difference between the patient groups or between these and patients with neurological disease. These findings suggest a reduced neuronal activity in the 5-hydroxytryptaminergic system in some depressed patients rather than an absolute deficiency of tryptophan-5-hydroxylase. The synthesis of 5-HIAA in response to tryptophan varied with age.

This paper reviews the recent experimental evidence bearing on the issue of the psychological reality of the phoneme, particularly its general CLASS character, the relative NON-DISCRIMINABILITY of its positional variants (allophones), and its status as a discrete SEGMENT. Evidence bearing on a few selected problems of English phonemics is also discussed. All of the experiments cited, however, seem to have been to some extent contaminated by orthographic effects; moreover, a host of other studies go so far as to suggest that knowledge of spelling may not only impinge critically on phonological judgements, but that the very ability to segment speech may be a by-product of learning an alphabetic orthography. But as the experiments to date have been largely restricted to overt judgements about a rather limited range of words, the possibility still remains open that a phonemic segmentation of speech may well occur at an unconscious, perceptual level even in the pre-literate period.

This paper reports the comparative antimalarial efficacy of intravenous artelinate and artesunate in rats. Prior to efficacy experiments, a Plasmodium berghei–Sprague-Dawley rat model of malaria was developed, in which the clearance effects of intravenous drugs could be readily compared. In efficacy experiments, groups of P. berghei-infected rats were given 3 daily intravenous treatments of artelinate or artesunate at molar equivalent dose rates (total of 0–191·2 μmoles/kg). Artelinate was superior to artesunate in terms of clearance (100% clearance dose of 95·6 μmoles/kg (40 mg/kg) versus 191·2 μmoles/kg for AS (73·4 mg/kg)) and parasite clearance time (1·7±0·5 days for AL versus 2·7±0·5 days for AS at a dose rate of 191·2 μmoles/kg, P<0·01). No frank clinical toxicity was observed, though both artesunate and artelinate induced dose-related vascular necrosis at the site of injection. The necrosis was less severe and reversible when the drugs were administered via femoral, rather than tail/foot veins. The data suggest that the P. berghei–7-week-old Sprague-Dawley rat model of malaria is reproducible and useful for assessing the efficacy of antimalarials and that artelinate is at least as potent, and safe, as artesunate, the leading clinical treatment for severe malaria.

Although food handlers are often implicated as the source of infection in outbreaks of food-borne viral gastroenteritis, little is known about the timing of infectivity in relation to illness. We investigated a gastroenteritis outbreak among employees of a manufacturing company and found an association (RR=14·1, 95% CI=2·0–97·3) between disease and eating sandwiches prepared by 6 food handlers, 1 of whom reported gastroenteritis which had subsided 4 days earlier. Norwalk-like viruses were detected by electron microscopy or reverse transcriptase-polymerase chain reaction (RT-PCR) in stool specimens from several company employees, the sick food handler whose specimen was obtained 10 days after resolution of illness, and an asymptomatic food handler. All RT-PCR product sequences were identical, suggesting a common source of infection. These data support observations from recent volunteer studies that current recommendations to exclude food handlers from work for 48–72 h after recovery from illness may not always prevent transmission of Norwalk-like viruses because virus can be shed up to 10 days after illness or while exhibiting no symptoms.

Like many research institutions, the Harvard-Smithsonian Center for Astrophysicsf (CfA), has been actively engaged in education and public outreach activities for many years. The Harvard University Department of Astronomy, the formal higher education arm of the CfA, offers an undergraduate concentration and a doctoral program. In our Science Education Department, educational researchers manage ten programs that address the needs of teachers and students (K-12 and college), through advanced technology, teacher enhancement programs, and the development of curriculum materials. The Editorial and Public Affairs Department offers several public lecture series, recorded sky information, children's nights, and runs the Whipple Observatory Visitors Center in Amado, AZ. In this environment of successful programs, the High Energy Astrophysics (HEA) division, one of seven research divisions at the CfA, has initiated, or partnered with other institutions, development of several new education and outreach programs. Some of these programs involve partnerships with the education community, but all of them have been initiated by and involve scientists.

We say that a positive integer d has property (A) if for all positive integers m there is an integer x, depending on m, such that, setting n = m + d, x lies between m and n and x is co-prime to mn. We show that infinitely many even d and infinitely many odd d have property (A) and that infinitely many even d do not have property (A). We conjecture and provide supporting evidence that all odd d have property (A).

Following A. R. Woods [3] we then describe conditions (Au) (for each u) asserting, for a given d, the existence of a chain of at most u + 2 integers, each co-prime to its neighbours, which start with m and increase, finishing at n = m + d. Property (A) is equivalent to condition (A1), and it is easily shown that property (Ai) implies property (Ai+1). Woods showed that for some u all d have property (Au), and we conjecture and provide supporting evidence that the least such u is 2.