To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Objectives: Despite changes to brain integrity with aging, some functions like basic language processes remain remarkably preserved. One theory for the maintenance of function in light of age-related brain atrophy is the engagement of compensatory brain networks. This study examined age-related changes in the neural networks recruited for simple language comprehension. Methods: Sixty-five adults (native English-speaking, right-handed, and cognitively normal) aged 17–85 years underwent a functional magnetic resonance imaging (fMRI) reading paradigm and structural scanning. The fMRI data were analyzed using independent component analysis to derive brain networks associated with reading comprehension. Results: Two typical frontotemporal language networks were identified, and these networks remained relatively stable across the wide age range. In contrast, three attention-related networks showed increased activation with increasing age. Furthermore, the increased recruitment of a dorsal attention network was negatively correlated to gray matter thickness in temporal regions, whereas an anterior frontoparietal network was positively correlated to gray matter thickness in insular regions. Conclusions: We found evidence that older adults can exert increased effort and recruit additional attentional resources to maintain their reading abilities in light of increased cortical atrophy.
Psychotropic medication use and psychiatric symptoms during pregnancy each are associated with adverse neurodevelopmental outcomes in offspring. Commonly, studies considering medication effects do not adequately assess symptoms, nor evaluate children when the effects are believed to occur, the fetal period. This study examined maternal serotonin reuptake inhibitor and polypharmacy use in relation to serial assessments of five indices of fetal neurobehavior and Bayley Scales of Infant Development at 12 months in N = 161 socioeconomically advantaged, non-Hispanic White women with a shared risk phenotype, diagnosed major depressive disorder. On average fetuses showed the expected development over gestation. In contrast, infant average Bayley psychomotor and mental development scores were low (M = 84.10 and M = 89.92, range of normal limits 85–114) with rates of delay more than 2–3 times what would be expected based on this measure's normative data. Controlling for prenatal and postnatal depressive symptoms, prenatal medication effects on neurobehavioral development were largely undetected in the fetus and infant. Mental health care directed primarily at symptoms may not address the additional psychosocial needs of women parenting infants. Speculatively, prenatal serotonin reuptake inhibitor exposure may act as a plasticity rather than risk factor, potentially enhancing receptivity to a nonoptimal postnatal environment in some mother–infant dyads.
Introduction: The optimal diagnostic strategy for children presenting to the Emergency Department (ED) with suspected appendicitis (SA), the most common non-traumatic surgical emergency in children, remains unclear. This study aims to identify which investigations and management priorities are preferred by Canadian surgeons prior to consultation from the ED. Methods: An internet survey was extended to practicing surgeons who are members of the Canadian Association of Pediatric Surgeons and Canadian Association of General Surgeons. Three case-based scenarios evaluated surgeons expected ED investigations and management for SA with varying severity of disease (simple - SA vs perforated - PA) and sex (male vs female). Differences across scenarios were determined by ANOVA and direct comparisons were reported using proportions and odds ratios with 95% confidence intervals. Results: Surveys were completed by 82 surgeons. Across the 3 cases, CBC (227/246, 92.3%) and urinalysis (188/246, 76.4%) were the sole investigations expected in >75% of responses. Expectations differed across cases for use of blood cultures (p<0.001), electrolytes (p<0.001), sexually transmitted infection testing (0.015) and ultrasound (US) (p<0.001). Blood cultures (26/82, 31.7% vs 4/82, 4.9%; OR 9.05 95%CI 2.88-37.33) and electrolytes (58/82, 70.7% vs 33/82, 40.2%; OR 3.59 95%CI 1.79-7.24) were expected more often in severe disease. US was expected more often in females (58/82,70.7% vs 25/82, 30.5%; OR 5.51, 95% CI 2.68-11.38). Expected management differed across cases for fluid boluses (p=0.01), intravenous (IV) analgesia (p<0.001) and antibiotics (p<0.001), with all differences attributed to severity of illness (fluids 73/82, 89.0% vs 59/82, 72.0% OR 3.16 95%CI 1.28-8.33; IV analgesia 66/82, 80.5% vs 42/82, 51.2% OR 3.93 95%CI 1.86-8.45; antibiotics 44/82, 53.7% vs 10/82, 12.2% OR 8.34 95%CI 3.59-20.44). Conclusion: Severity of illness and sex of the child impact the ED investigations and management expected by surgeons consulted for suspected appendicitis. Further research focusing on how these expectations influence patient outcomes should be conducted. Collaborative ED-surgery protocols for the diagnosis and management of acute appendicitis in children should be established.
The foetal mammary gland is sensitive to maternal weight and nutrition during gestation, which could affect offspring milk production. It has previously been shown that ewes born to dams offered maintenance nutrition during pregnancy (day 21 to 140 of gestation) produced greater milk, lactose and CP yields in their first lactation when compared with ewes born to dams offered ad libitum nutrition. In addition, ewes born to heavier dams produced greater milk and lactose yields when compared with ewes born to lighter dams. The objective of this study was to analyse and compare the 5-year lactation performance of the previously mentioned ewes, born to heavy or light dams that were offered maintenance or ad libitum pregnancy nutrition. Ewes were milked once per week, for the first 6 weeks of their lactation, for 5 years. Using milk yield and composition data, accumulated yields were calculated over a 42-day period for each year for milk, milk fat, CP, true protein, casein and lactose using a Legendre orthogonal polynomial model. Over the 5-year period, ewes born to heavy dams produced greater average milk (P=0.04), lactose (P=0.01) and CP (P=0.04) yields than offspring born to light dams. In contrast, over the 5-year period dam nutrition during pregnancy did not affect average (P>0.05) offspring milk yields or composition, but did increase milk and lactose accumulated yield (P=0.03 and 0.01, respectively) in the first lactation. These results indicate that maternal gestational nutrition appears to only affect the first lactational performance of ewe offspring. Neither dam nutrition nor size affected grand-offspring live weight gain to, or live weight at weaning (P>0.05). Combined these data indicate that under the conditions of the present study, manipulating dam weight or nutrition in pregnancy can have some effects of offspring lactational performance, however, these effects are not large enough to alter grand-offspring growth to weaning. Therefore, such manipulations are not a viable management tool for farmers to influence lamb growth to weaning.
Social anxiety disorder involves fear of social objects or situations. Social referencing may play an important role in the acquisition of this fear and could be a key determinant in future biomarkers and treatment pathways. However, the neural underpinnings mediating such learning in social anxiety are unknown. Using event-related functional magnetic resonance imaging, we examined social reference learning in social anxiety disorder. Specifically, would patients with the disorder show increased amygdala activity during social reference learning, and further, following social reference learning, show particularly increased response to objects associated with other people's negative reactions?
A total of 32 unmedicated patients with social anxiety disorder and 22 age-, intelligence quotient- and gender-matched healthy individuals responded to objects that had become associated with others’ fearful, angry, happy or neutral reactions.
During the social reference learning phase, a significant group × social context interaction revealed that, relative to the comparison group, the social anxiety group showed a significantly greater response in the amygdala, as well as rostral, dorsomedial and lateral frontal and parietal cortices during the social, relative to non-social, referencing trials. In addition, during the object test phase, relative to the comparison group, the social anxiety group showed increased bilateral amygdala activation to objects associated with others’ fearful reactions, and a trend towards decreased amygdala activation to objects associated with others’ happy and neutral reactions.
These results suggest perturbed observational learning in social anxiety disorder. In addition, they further implicate the amygdala and dorsomedial prefrontal cortex in the disorder, and underscore their importance in future biomarker developments.
Paragonimus westermani is one of the most medically important lung flukes and is widely distributed in Asia. It exhibits considerable variation in morphological, genetic and biological features. In central provinces of Vietnam, a high prevalence of metacercariae of this species has been reported from the crab intermediate host, Vietopotamon aluoiense. In this study, we detected P. westermani metacercariae in two additional crab hosts, Donopotamon haii in Quang Tri Province, central Vietnam and Indochinamon tannanti in Yen Bai Province in the north. The latter is a new locality for P. westermani in a northern region of Vietnam where P. heterotremus is the only species currently known to cause human paragonimiasis. Paragonimus westermani metacercariae found in Vietnam showed considerable morphological variation but slight genetic variation based on DNA sequences from the nuclear ribosomal ITS2 region and the mitochondrial 16S gene. Co-infection of the same individual crabs with P. westermani and P. heterotremus and/or some other Paragonimus species was found frequently, suggesting potential for co-infection in humans. The findings of the present study emphasize the need for highly specific molecular and immunodiagnostic methods to differentially diagnose between P. westermani and P. heterotremus infections.
Both physical activity (PA) and diet are important contributors to health and well-being; however, there is limited information on the association of these behaviours and whether observed associations differ by weight. The present study aimed to evaluate whether nutrient intake is associated with PA and if this association varies by weight in young adults.
Cross-sectional study to analyse the association between PA and nutrient intake.
Participants were stratified as normal weight (18·5 kg/m2 <BMI <25·0 kg/m2) and overweight/obese (BMI≥25·0 kg/m2). PA level (PAL) was calculated (PAL=total daily energy expenditure/RMR) and used to stratify groups (PAL<1·6, 1·6≤PAL<1·9, PAL≥1·9).
Adults (n 407; age 27·6 (sd 3·8) years, 48 % male), with BMI between 20 and 35 kg/m2, having at least two 24 h diet recalls and at least 5 d (including two weekend days) of valid, objectively measured PA data were included in the analysis.
In normal-weight participants, higher PAL was associated with higher intakes of minerals (except Ca, Fe and Zn), B-vitamins and choline (P for trend <0·05). In the overweight/obese group, higher PAL was associated with higher intakes of fibre, K, Na and Cu (P for trend <0·05). These differences, however, were no longer significant after additionally controlling for total energy intake.
More active young adults have higher intakes of essential micronutrients. The benefits of PA may be predominantly due to a higher overall food intake while maintaining energy balance rather than a healthier diet.
Here, we report the feasibility and long-term efficacy of a granulomatous slack skin disease (GSSD) treatment with combined high-energy photon and proton beams.
Patient and methods
A GSSD patient with abdominal disease volume 25×15×2–4 cm deep was recommended for treatment at this institution. In addition to photons and electrons, high-energy protons delivered with advanced planning techniques and patient positioning were used. The patient was irradiated to a total dose of 40 Gy by using 20 Gy matched photon and electrons followed by 20 Gy equivalent protons delivered by using innovative range compensation and patient positioning.
The test patient tolerated the treatment well and is now a 10-year survivor of the disease.
Treatment of GSSD with protons is feasible. The range and narrow penumbra properties of the proton beam provided an ideal capability to match fields accurately to cover large volumes while also sparing underlying normal tissues.
This chapter reviews evidence concerning the vital role that temporal dynamics can have in the ecology of trees and other long-lived species in the assembly and maintenance of natural communities. The research synthesised here was stimulated by a desire to determine the action of temporal dynamics in nature, and its implications for the nature of competition, community structure and assembly on multiple scales and across a range of climatic conditions. For the most part, the results discussed concern tropical forests, but we think they provide strong support for a more general view that can be applied across biomes. Finally, we ask if there may be a potential role for temporal dynamics in speciation, in light of what we have learned from the tropical trees.
A field programme begun in the late ’90s in the tropical dry forest of México was consciously designed to study the coexistence of closely related species in a very speciose community, but the role of temporal dynamics had not been suspected and its finding was serendipitous. With centuries-long lifespans, decades-long juvenile stages and low population turnover rates, trees are problematic candidates for demographic analyses, either observational or experimental. Unless instant death is involved, the particular hurdle with trees, as with any long-lived organism, is directly connecting any specific response in the early life of the individual with the long-term individual persistence or character of the standing population. However, trees differ from many long-lived organisms in carrying their history in their structure at both the individual and population levels. Thus, a tree population itself documents individual success over the history of the population (Parker et al. 1997, Cole et al. 2011). The distribution of a population with regard to physical conditions, size and age structure and relative to other woody species all contain information on the ecology and interactions of species (e.g. Veblen 1989, 1992, Villalba and Veblen 1998, Kelly et al. 2001) and it was the age structure of populations that revealed the action of temporal dynamics at Chamela Biological Station.
Research is essential for the development of evidence-based emergency medical services (EMS) systems of care. When resources are scarce and gaps in evidence are large, a national agenda may inform the growth of EMS research in Canada. This mixed methods consensus study explores current barriers and existing strengths within Canadian EMS research, provides recommendations, and suggests EMS topics for future study.
Purposeful sampling was employed to invite EMS research stakeholders from various roles across the country. Study phases consisted of 1) baseline interviews of a subsample, 2) roundtable discussion, and 3) an online Delphi survey, in which participants scored each statement for importance. Consensus was defined a priori and met if 80% scored a statement as “important” or “very important.”
Fifty-three stakeholders participated, representing researchers (37.7%), EMS administrators (24.6%), clinicians/ providers (20.7%), and educators (17.0%). Participation rates were as follows: interviews, 13 of 13 (100%); roundtable, 47 of 53 (89%); survey round 1, 50 of 53 (94%); survey round 2, 47 of 53 (89%); and survey round 3, 40 of 53 (75%). A total of 141 statements were identified as important: 20 barriers, 54 strengths/opportunities, 31 recommendations, and 36 suggested topics for future research. Like statements were synthesized, resulting in barriers (n 5 10), strengths/opportunities (n 5 24), and recommendations (n 5 19), which were categorized as time, opportunities, and funding; education and mentorship; culture of research and collaboration; structure, process, and outcome of research; EMS and paramedic practice; and the future of the EMS Research Agenda.
Consensus-based key messages from this agenda should be considered when designing, funding, and publishing EMS research and will advance EMS research locally, regionally, and nationally.
This study forms the first phase in the development of the Canadian National EMS Research Agenda. The purpose was to understand the current state of emergency medical services (EMS) research through the barriers and opportunities perceived by key stakeholders in the Canadian system and to identify the recommendations this group had for moving forward.
This qualitative study was conducted in the spring of 2011 using one-on-one semistructured telephone interviews. Purposeful sampling was used to recruit a cross section of EMS research stakeholders, representing a breadth of geographic regions and roles. Data were collected until thematic saturation was reached. A constant comparative approach was used to develop a basic coding framework and identify emerging themes.
Twenty stakeholders were invited to participate, and saturation was reached after 13 interviews. Thematic saturation was used to ensure that the findings were grounded in the data. Four major themes were identified: 1) the need for additional research education within EMS; 2) the importance of creating an infrastructure to support pan-Canadian research collaboration; 3) addressing the complexities of involving EMS providers in research; and 4) considerations for a national research agenda.
This hypothesis-generating study reveals key areas regarding EMS research in Canada and through the guidance it provides is a first step in the development of a comprehensive national research agenda. Our intention is to collate the identified themes with the results of a larger roundtable discussion and Delphi survey and, in doing so, guide development of a Canadian national EMS research agenda.
India is the second most populous nation in the world after China, and its plant genetic resources are an important basis for crop improvement to meet human population needs. An important legume in the diet of the Indian population is common bean (Phaseolus vulgaris L.). Common beans are one of the many important legumes grown in India, but unlike others, its centre of origin is not in Asia but in the Americas. The objective of this study was to evaluate two collections of Indian common beans: one for an internationally available collection of Food and Agriculture Organization (FAO)-protected accessions and one from the north-western Himalayan region. In total, 149 Indian landraces were evaluated with a total of 24 microsatellites across the two collections, and these represented all common bean-growing states of India. A population structure analysis was used to find groups in each collection, and this was compared across the collections. The genetic analysis of the two sets of Indian accessions with neighbour-joining trees and principal component analysis categorized the landraces into Andean and Mesoamerican gene pool groups. The Andean genotypes dominated the north-western Himalayan collection while the FAO-protected accessions were predominantly Mesoamerican. The Indian subcontinent can be considered as a region of high bean diversity; however, very little introgression was observed between the gene pools in both the germplasm sets. Gene pool identity was further substantiated by the comparison of seed traits, particularly seed size. The role of the landraces in plant breeding programmes is discussed.
Obesity and sarcopenia are health problems associated with ageing. The present study modelled the longitudinal changes in body composition of healthy men, aged from 20 to 96 years, and evaluated the fidelity of BMI to identify age-dependent changes in fat mass and fat-free mass. The data from 7265 men with multiple body composition determinations (total observations 38 328) were used to model the age-related changes in body mass, fat mass, fat-free mass, BMI and percentage of body fat. Changes in fat mass and fat-free mass were used to evaluate the fidelity of BMI and to detect body composition changes with ageing. Linear mixed regression models showed that all trajectories of body composition with healthy ageing were quadratic. Fat mass, BMI and percentage of body fat increased from age 20 years and levelled off at approximately 80 years. Fat-free mass increased slightly from age 20 to 47 years and then declined at a non-linear rate with ageing. Levels of aerobic exercise had a positive influence on fat mass and a slight negative effect on fat-free mass. BMI and percentage of body fat were sensitive in detecting the increase in fat mass that occurred with healthy ageing, but failed to identify the loss of fat-free mass that started at age 47 years.
Seven ternary mixtures of gold(80-95%)-silver(4-15%)-copper(1-15%) were prepared as standards for the determination of elemental composition by energy dispersive X-ray spectrometry (EDS). Two geometric forms (flat and oblate) of the standards were prepared for comparison to the analyses of historic gold objects. Surface analyses were performed. Polished sections of the standards were also analysed Comparison between two methods for collecting EDS data is reported. The analyses are discussed in terms of developing a generalized methodology for estimating elemental composition of museum artifacts.
Gamma- and UV-induced defect centers in germanium and fluorine doped silica have been studied by electron paramagnetic resonance (EPR) spectroscopy. The complex spectrum at g≃2 in γ-irradiated germanium doped glass corresponds to a superposition of resonances from several germanium E′-centers. In UV-irradiated samples, however, the EPR spectrum is dominated by only one type of germanium E′-centers. Significant spectral simplification of γ-irradiated germanium doped silica can be achieved by heating or broadband photoirradiation. Similar results are observed in multimode germanium doped core optical fibers. UV-induced optical loss spectra in the 0.5–1.5 μm wavelength range were also measured in these core fibers as well as the growth kinetics of the UL-induced absorption. Gamma-irradiation of fluorine doped silica generated two different types of silicon E′-centers, Ea1. At lower radiation dose one sees a mixture of Ea1 and Ea2, but at higher radiation dose Ea2 dominates. A spectrum dominated by the Ea2 variant is also observed in LW-irradiated samples and in photobleached low gamma dose samples.
The cognitive profile of early onset Parkinson’s disease (EOPD) has not been clearly defined. Mutations in the parkin gene are the most common genetic risk factor for EOPD and may offer information about the neuropsychological pattern of performance in both symptomatic and asymptomatic mutation carriers. EOPD probands and their first-degree relatives who did not have Parkinson’s disease (PD) were genotyped for mutations in the parkin gene and administered a comprehensive neuropsychological battery. Performance was compared between EOPD probands with (N = 43) and without (N = 52) parkin mutations. The same neuropsychological battery was administered to 217 first-degree relatives to assess neuropsychological function in individuals who carry parkin mutations but do not have PD. No significant differences in neuropsychological test performance were found between parkin carrier and noncarrier probands. Performance also did not differ between EOPD noncarriers and carrier subgroups (i.e., heterozygotes, compound heterozygotes/homozygotes). Similarly, no differences were found among unaffected family members across genotypes. Mean neuropsychological test performance was within normal range in all probands and relatives. Carriers of parkin mutations, whether or not they have PD, do not perform differently on neuropsychological measures as compared to noncarriers. The cognitive functioning of parkin carriers over time warrants further study. (JINS, 2011, 17, 1–10)