Memory and comprehension for health information among older adults: distinguishing the effects of domain-general and domain-specific knowledge

While there is evidence that knowledge influences understanding of health information, less is known about the processing mechanisms underlying this effect and its impact on memory. We used the moving window paradigm to examine how older adults varying in domain-general crystallised ability (verbal ability) and health knowledge allocate attention to understand health and domain-general texts. Participants (n = 107, age: 60-88 years) read and recalled single sentences about hypertension and about non-health topics. Mixed-effects modelling of word-by-word reading times suggested that domain-general crystallised ability increased conceptual integration regardless of text domain, while health knowledge selectively increased resource allocation to conceptual integration at clause boundaries in health texts. These patterns of attentional allocation were related to subsequent recall performance. Although older adults with lower levels of crystallised ability were less likely to engage in integrative processing, when they did, this strategy had a compensatory effect in improving recall. These findings suggest that semantic integration during reading is an important comprehension process that supports the construction of the memory representation and is engendered by knowledge. Implications of the findings for theories of text processing and memory as well as for designing patient education materials are discussed

Interactions between climatic variables controlling subalpine tree growth: implications for climatic history of the Sierra Nevada, California

EXTRACT (SEE PDF FOR FULL ABSTRACT): Tree-ring records from foxtail pine (Pinus balfouriana) and western juniper (Juniperus occidentalis) growing near tree line in the eastern Sierra Nevada, California, show strong correlations with summer temperature and winter precipitation. Response surfaces portraying tree growth as a function of summer temperature and winter precipitation indicate a strong interaction between these variables in controlling growth. ... Above average growth for both foxtail pine and western juniper from AD 1480 to 1570 can be interpreted as indicating an extended period of warm, moist conditions unequalled during the 20th century

Duration and severity of Medieval drought in the Lake Tahoe Basin

This paper is not subject to U.S. copyright. The definitive version was published in Quaternary Science Reviews 30 (2011): 3269-3279, doi:10.1016/j.quascirev.2011.08.015.Droughts in the western U.S. in the past 200 years are small compared to several megadroughts that occurred during Medieval times. We reconstruct duration and magnitude of extreme droughts in the northern Sierra Nevada from hydroclimatic conditions in Fallen Leaf Lake, California. Stands of submerged trees rooted in situ below the lake surface were imaged with sidescan sonar and radiocarbon analysis yields an age estimate of ∼1250 AD. Tree-ring records and submerged paleoshoreline geomorphology suggest a Medieval low-stand of Fallen Leaf Lake lasted more than 220 years. Over eighty more trees were found lying on the lake floor at various elevations above the paleoshoreline. Water-balance calculations suggest annual precipitation was less than 60% normal from late 10th century to early 13th century AD. Hence, the lake’s shoreline dropped 40–60 m below its modern elevation. Stands of pre-Medieval trees in this lake and in Lake Tahoe suggest the region experienced severe drought at least every 650–1150 years during the mid- and late-Holocene. These observations quantify paleo-precipitation and recurrence of prolonged drought in the northern Sierra Nevada.Support for this work was provided by US Geological Survey/ Desert Research Institute under Project ID# 2003NV39B, a Geological Society of America graduate research grant and the IRIS undergraduate internship program. F. Biondiwas supported, in part by NSF Cooperative Agreement EPS-0814372 to the Nevada System of Higher Education. N. Driscoll was supported in part by a grant from CA DWR

The value of paleoecology as an aid to monitoring ecosystems and landscapes, chiefly with reference to North America

Paleoecological indicators are examined as to their accuracy in reconstructing past biotic communities and environmental conditions, their utility in answering important questions about such communities and conditions, and the temporal and spatial scales over which they are effective. Next, environmental problems susceptible of paleoecological analysis are considered, as are the ecosystem and landscape properties that can be inferred from such an analysis. The usefulness of paleoecology in anticipating ecological surprises is then discussed. Finally, a set of conclusions and recommendations is presented

Software design to facilitate information transfer at hospital discharge

Discharge communication between inpatient and outpatient physicians is often an inefficient and error-prone process. Adverse events result from poor communication at the time of discharge. The objective of this study was to describe development of discharge software to overcome communication barriers. The secondary objective was to assess factors that influence the time to complete tasks with the software. Methods were a performance improvement model and database analysis of 336 discharges. Software design specifications included computerised physician order entry, immediate utility, minimal development and deployment costs, acceptability to physician-users, and satisfaction of primary care physicians, patients and pharmacists. Design features included simple 'just-in-time' prompts and point-of-care prescribing resources. The dependent variable for analysis was physician time to complete discharge prescriptions and instructions while using the software. General linear and mixed-effects regression models adjusted for physician effects and other predictors. Results revealed that physician factors significantly affected the time to complete a discharge while using the software. As the number of accesses (log-ins) and free text typing increased, then time to complete the computerised discharge increased. Patient-related factors that increased physician time were discharge diagnoses, prescriptions and length of stay. In conclusion, discharge software can help inpatient physicians transfer timely, complete and legible information to outpatient physicians, pharmacists and patients. Physician and patient factors influence the time to complete discharges using the software

Spatial Variation in Distribution and Growth Patterns of Old Growth Strip-Bark Pines

Postindustrial rises in CO2 have the potential to confound the interpretation of climatically sensitive tree-ring chronologies. Increased growth rates observed during the 20th century in strip-bark trees have been attributed to CO2 fertilization. Absent in the debate of CO2 effects on tree growth are spatially explicit analyses that examine the proximate mechanisms that lead to changes in rates of tree growth. Twenty-seven pairs of strip-bark and companion entire-bark trees were analyzed in a spatially explicit framework for abiotic environmental correlates. The strip-bark tree locations were not random but correlated to an abiotic proxy for soil moisture. The strip-bark trees showed a characteristic increase in growth rates after about 1875. Furthermore, the difference in growth rates between the strip-bark trees and entire-bark companions increased with increasing soil moisture. A possible mechanism for these findings is that CO2 is affecting water-use efficiency, which in turn affects tree-ring growth. These results point to the importance of accounting for microsite variability in analyzing the potential role of CO2 in governing growth responses

Emergent climate and CO2 sensitivities of net primary productivity in ecosystem models do not agree with empirical data in temperate forests of eastern North America

Ecosystem models show divergent responses of the terrestrial carbon cycle to global change over the next century. Individual model evaluation and multi-model comparisons with data have largely focused on individual processes at sub-annual to decadal scales. Thus far, data-based evaluations of emergent ecosystem responses to climate and CO2 at multi-decadal and centennial time scales have been rare. We compared the sensitivity of net primary productivity (NPP) to temperature, precipitation, and CO2 in ten ecosystem models with the sensitivities found in tree-ring reconstructions of NPP and raw ring-width series at six temperate forest sites. These model-data comparisons were evaluated at three temporal extents to determine whether the rapid, directional changes in temperature and CO2 in the recent past skew our observed responses to multiple drivers of change. All models tested here were more sensitive to low growing season precipitation than tree-ring NPP and ring widths in the past 30 years, although some model precipitation responses were more consistent with tree rings when evaluated over a full century. Similarly, all models had negative or no response to warm growing season temperatures while tree-ring data showed consistently positive effects of temperature. Although precipitation responses were least consistent among models, differences among models to CO2 drive divergence and ensemble uncertainty in relative change in NPP over the past century. Changes in forest composition within models had no effect on climate or CO2 sensitivity. Fire in model simulations reduced model sensitivity to climate and CO2, but only over the course of multiple centuries. Formal evaluation of emergent model behavior at multi-decadal and multi-centennial time scales is essential to reconciling model projections with observed ecosystem responses to past climate change. Future evaluation should focus on improved representation of disturbance and biomass change as well as the feedbacks with moisture balance and CO2 in individual models