The early stages of leukaemia

Of recent years there has been a growing literature on the subject of leukaemia in its earlier stages, and it is becoming apparent that conditions formerly thought to be separate entities, are actually unusual manifestations of a well recognised type. Thus the classification and nomenclature tends to become simplified, and terms such as "leucanaemia" and "mixed leukaemia" are passing into disuse, although such a horror as "aleukaemic leukaemia" still survives to offend the aesthetic sense. The difficulty remains that apparently the marrow may be the seat of a leukaemic process before the blood is affected.But although more attention is being paid to these early cases, the literature available is still very small as compared with that on fully established leukaemia, partly because the early condition may pass unrecognised as such, and partly because the onset is so insidious that patients do not seek advice until an advanced stage is reached.Six cases in all are reported herein, three acute, and three chronic. These were all admitted to the Royal Infirmary of Edinburgh under the charge of Dr Goodall to whom I am indebted for facilities to study them. Of the acute cases, two are lymphatic leukaemia, and one chloroma, the others are chronic lymphatic leukaemia, one of them occurring some years after the successful treatment of B anti's disease

The history of the island of Rhodes

[OCR failure

'It's on your conscience all the time': a systematic review of qualitative studies examining views on obesity among young people aged 12-18 years in the UK

OBJECTIVE: To explore the perspectives of young people in the UK on obesity, body size, shape and weight. DESIGN: Systematic review of qualitative studies using thematic synthesis. DATA SOURCES: Sensitive searches of 18 electronic databases from 1997 to February 2010 supplemented by grey literature searches. STUDY SELECTION: Studies produced since 1997 using qualitative methods to collect perspectives of people aged 12-18 years in the UK, reporting methods for data collection or analysis. Studies of people with eating disorders and those rated low in reliability and usefulness were excluded. RESULTS: Searches identified 30 studies involving over 1400 young people from a range of contexts. Young people of all sizes placed considerable emphasis on personal responsibility, and on the social, rather than health implications of being overweight. Young people with experience of obesity described severe, unrelenting, size-related abuse and isolation. Regardless of their own size, young people were judgemental of individuals who were overweight, but those with experience of obesity described an environment that contained multiple barriers to weight loss. Only one study asked young people directly what might support them to have a healthy body size. Study findings were configured under three main themes, labelled with quotes from included studies: general perceptions of size and society's responses ('It's on your conscience all the time'); the experiences of young people who were overweight ('If I had the choice I wouldn't be this size') and these larger young people's experiences of trying to loose weight and suggestions for action ('Make sure, even when it's hard, you've got people there'). CONCLUSIONS: The perspectives of young people in the UK, when synthesised across the spectrum of body sizes, paint a picture of a stigmatising and abusive social world. Research and policy need to engage young people actively so as to address the social implications of obesity

Influence of resource pulses and perennial neighbors on the establishment of an invasive annual grass in the Mojave Desert

Invasion by exotic annual grasses is one of the most significant threats to arid ecosystems in the western USA. Current theories of invasibility predict plant communities become more susceptible to invasion whenever there is an increase in the amount of unused resources. The objective of this field study was to examine how resource pulses and temporal variation in resource demand by the native shrub vegetation influences establishment of the invasive annual grass Schismus arabicus. Water and nitrogen were applied as pulses in early spring, mid-spring, or continuously throughout the growing season to plots containing either Atriplex confertifolia or Atriplex parryi shrubs. The effect of resource pulses on Schismus density and biomass was highly dependent on the seasonal timing of the resource pulses and the identity of the neighbor shrub. When resource pulses coincided with high rates of resource capture and growth of the native vegetation, density and biomass of Schismus was reduced. Schismusestablishment was greater under continuous resource supply compared to pulsed resource supply, likely because more soil resources were available at a shallow depth when resources were supplied at a continuous low rate. These results suggest that the establishment of invasive annual grasses in arid systems can be influenced by the magnitude and spatial distribution of resource pulses in addition to the seasonal timing of resource pulses

The Effect of Time Constraints on Older and Younger Driver Decisions to Turn at Intersections Using a Modified Change Blindness Paradigm

After age 75, the risk of intersection accident involvement for older drivers increases for most intersection maneuvers. Failure to yield right-of-way and violation of traffic controls are common citations. Previous research has argued that age-related declines in attentional breadth and switching can discriminate between those who are and are not more likely to be in an accident. The present study examined the effect of time constraints on older and younger driver intersection decisions. It was expected that less time to decide, process and act upon intersection decisions would adversely affect older drivers more so than younger drivers. The change blindness or flicker paradigm was modified to address these questions (see, e.g., Rensink, et al., 1997). Typically, an image (A) is alternated with a modified image (A’) each for a short duration (250 ms) with a blank field or mask (80 ms) between A and A’. In the present study, a focus screen (or prime) that indicated the expected direction of travel (i.e., left, right, or straight) was added prior to the alternation of images. Forty-eight images were selected from 2500 intersection approaches in Calgary, Winnipeg and Montreal that were filmed using a digital camera during the day. Photoshop was used to create the A’ images by manipulating a variety of elements including pedestrians, vehicles, signs, and signals. The goal of the participant was to decide if the indicated direction of travel in the pair of intersection images was safe (press accelerator) or not (press brake). Sixteen younger (M = 22.3) and 16 older drivers (M = 73.6) drivers were screened for visual acuity, contrast sensitivity, and medication use. Length of image alternation was the primary independent variable (4 and 8 s). As expected, older drivers were more likely to miss intersection changes at shorter exposure durations than younger drivers. A number of qualitative probes were also collected that clearly illustrate the contextual demands of intersections on attention. The implications of the results for intersection design and older driver selective attention are discussed

Interpretive analysis of 85 systematic reviews suggests narrative syntheses and meta-analyses are incommensurate in argumentation

Introduction. Using Toulmin’s argumentation theory, we analysed the texts of systematic reviews in the area of workplace health promotion to explore differences in the modes of reasoning embedded in reports of narrative synthesis as compared to reports of meta-analysis. Methods. We used framework synthesis, grounded theory and cross-case analysis methods to analyse 85 systematic reviews addressing intervention effectiveness in workplace health promotion. Results. Two core categories, or ‘modes of reasoning’, emerged to frame the contrast between narrative synthesis and meta-analysis: practical-configurational reasoning in narrative synthesis (‘what is going on here? what picture emerges?’) and inferential-predictive reasoning in meta-analysis (‘does it work, and how well? will it work again?’). Modes of reasoning examined quality and consistency of the included evidence differently. Meta-analyses clearly distinguished between warrant and claim, whereas narrative syntheses often presented joint warrant-claims. Conclusion. Narrative syntheses and meta-analyses represent different modes of reasoning. Systematic reviewers are likely to be addressing research questions in different ways with each method. It is important to consider narrative synthesis in its own right as a method and to develop specific quality criteria and understandings of how it is done, not merely as a complement to, or second-best option for, meta-analysis

Older and Younger Driver Performance at Complex Intersections: Implications for Using Perception-Response Time and Driving Simulation

Older drivers are at increased accident risk at intersections for a variety of maneuvers. To examine why, a study was conducted to assess older driver performance at complex intersections in a driving simulator. The University of Calgary Driving Simulator was used to test healthy older drivers (65-83, M = 71.4) and younger drivers (19-22, M = 20.7). Critical scenarios included the sudden appearance of a pedestrian in an intersection, a lastsecond yellow light, an unexpected change during a left, and a vehicle violating a stoplight. Older drivers had significantly higher perception response times (PRT) than younger drivers for the latter three of the four intersection scenarios. Analysis of specific maneuvers also revealed qualitative response differences between young and old groups. In contradiction to expectation, more older drivers ran the yellow light than younger drivers. The capability of older drivers to respond under time constraints is implicated. The utility of driving simulators to assess older driver performance at intersections was limited by the prevalence of simulator sickness

Older and Younger Driver Performance at Complex Intersections: Implications for Using Perception-Response Time and Driving Simulation

Older drivers are at increased accident risk at intersections for a variety of maneuvers. To examine why, a study was conducted to assess older driver performance at complex intersections in a driving simulator. The University of Calgary Driving Simulator was used to test healthy older drivers (65-83, M = 71.4) and younger drivers (19-22, M = 20.7). Critical scenarios included the sudden appearance of a pedestrian in an intersection, a lastsecond yellow light, an unexpected change during a left, and a vehicle violating a stoplight. Older drivers had significantly higher perception response times (PRT) than younger drivers for the latter three of the four intersection scenarios. Analysis of specific maneuvers also revealed qualitative response differences between young and old groups. In contradiction to expectation, more older drivers ran the yellow light than younger drivers. The capability of older drivers to respond under time constraints is implicated. The utility of driving simulators to assess older driver performance at intersections was limited by the prevalence of simulator sickness