Temperature and food quality can both influence growth rates, consumption rates, utilization efficiencies and developmental time of herbivorous insects. Gravimetric analyses were conducted during two consecutive years to assess the effects of temperature and food quality on fourth instar larvae of the forest tent caterpillar Malacosoma disstria Hübner. Larvae were reared in the laboratory at three different temperatures (18, 24 and 30 degrees C) and on two types of diet; leaves of sugar maple trees Acer saccharum Marsh. located at the forest edge (sun-exposed leaves) or within the forest interior (shade-exposed leaves). In general, larvae reared at 18 degrees C had lower growth rates and lower consumption rates than larvae reared at the warmer temperatures (24 and 30 degrees C). Moreover, the duration of the instar decreased significantly with increasing temperatures. Type of diet also affected the growth rates and amount of food ingested by larvae but did not affect the duration of the instar. Larvae fed sun-exposed leaves consumed more food and gained higher biomasses. Values of approximate digestibility and efficiency of conversion of ingested food were also higher when larvae were fed sun-exposed leaves. Higher growth rates with increasing temperatures were primarily the result of the shorter stadium duration. The higher growth rates of larvae fed sun-exposed leaves were possibly the result of stimulatory feeding and consequently greater food intake and also a more efficient use of food ingested. This study suggests that the performance of M. disstria caterpillars could be enhanced by warmer temperatures and higher leaf quality.

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Recent studies have supported a role for amyloid positron emission tomography (PET) imaging in distinguishing Alzheimer's disease (AD) pathology from other pathological protein accumulations leading to dementia. We investigated the clinical utility of amyloid PET in the differential diagnosis of atypical dementia cases and its impact on caregivers. Using the amyloid tracer 18F-NAV4694, we prospectively scanned 28 patients (mean age 59.3 y, s.d. 5.8; mean MMSE 21.4, s.d. 6.0) with an atypical dementia syndrome. Following a comprehensive diagnostic workup (i.e., history taking, neurological examination, blood tests, neuropsychological evaluation, MRI, and FDG-PET), no certain diagnosis could be arrived at. Amyloid PET was then conducted and classified as positive or negative. Attending physicians were asked to evaluate whether this result led to a change in diagnosis or altered management. They also reported their degree of confidence in the diagnosis. Caregivers were met after disclosure of amyloid PET results and completed a questionnaire/interview to assess the impact of the scan. Our cohort was evenly divided between positive (14/28) and negative (14/28) 18F-NAV4694 cases. Amyloid PET resulted in a diagnostic change in 9/28 cases (32.1%: 17.8% changed from AD to non-AD, 14.3% from non-AD to AD). There was a 44% increase in diagnostic confidence. Altered management occurred in 71.4% (20/28) of cases. Knowledge of amyloid status improved caregivers' outcomes in all domains (anxiety, depression, disease perception, future anticipation, and quality of life). This study suggests a useful additive role for amyloid PET in atypical cases with an unclear diagnosis beyond the extensive workup of a tertiary memory clinic. Amyloid PET increased diagnostic confidence and led to clinically significant alterations in management. The information gained from that test was well received by caregivers and encouraged spending quality time with their loved ones.

Our results suggest a benefit from the influenza vaccination and support an annual vaccination strategy for elderly people with cardiac diseases.

Variations of leaf suitability within forest canopies may have important consequences for the biology of phytophagous insects. In this study we examined over 4 consecutive years (1994–1997), the influence of vertical stratification of leaves within a sugar maple (Acer saccharum Marsh.) stand on biological performance and feeding preference of Malacosoma disstria Hbn. Each year, 10 healthy sugar maple trees and about 15 understory sugar maple seedlings were selected. Leaves were collected from the lower (3–6 m above ground) and the upper crown (20–25 m above ground) sections of the trees and from seedlings. Sampled leaves were set in Petri dishes for insect rearings in controlled environment. The performance of the insect, especially pupal masses and the number of eggs of adult females, was higher when larvae were fed with leaves from the upper crown section of trees. Results for the feeding preference tests showed that larvae of fourth instars consumed more surface area from leaves collected in the upper crown section of the trees. More total nitrogen found in leaves from the upper tree crown could explain the higher performance of this insect. Our results confirm the importance of the heterogeneity in leaf suitability along a vertical stratification in forests by its influence on biological performance and feeding preference of M. disstria.