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Anterograde interference emerges when two differing tasks are learned in close temporal proximity, an effect repeatedly attributed to a competition between differing task memories. However, recent development alternatively suggests that initial learning may trigger a refractory period that occludes neuroplasticity and impairs subsequent learning, consequently mediating interference independently of memory competition. Accordingly, this study tested the hypothesis that interference can emerge when the same motor task is being learned twice, that is when competition between memories is prevented. In a first experiment, the inter-session interval (ISI) between two identical motor learning sessions was manipulated to be 2 min, 1 h or 24 h. Results revealed that retention of the second session was impaired as compared to the first one when the ISI was 2 min but not when it was 1 h or 24 h, indicating a time-dependent process. Results from a second experiment replicated those of the first one and revealed that adding a third motor learning session with a 2 min ISI further impaired retention, indicating a dose-dependent process. Results from a third experiment revealed that the retention impairments did not take place when a learning session was preceded by simple rehearsal of the motor task without concurrent learning, thus ruling out fatigue and confirming that retention is impaired specifically when preceded by a learning session. Altogether, the present results suggest that competing memories is not the sole mechanism mediating anterograde interference and introduce the possibility that a time- and dose-dependent refractory period—independent of fatigue—also contributes to its emergence. One possibility is that learning transiently perturbs the homeostasis of learning-related neuronal substrates. Introducing additional learning when homeostasis is still perturbed may not only impair performance improvements, but also memory formation. [ABSTRACT FROM AUTHOR]

The article describes the development of the web-based Canadian Forest Service climate change indicator system, referred to as the Forest Change Tracking System. This indicator system was established in 2011 with financial support from the Adaptation theme of the Government of Canada Clean Air Agenda. The objectives of the Forest Change Tracking System are to (a) raise awareness and inform on the occurrence and scope of ongoing changes across Canadian forests associated with climate change and to (b) support the inclusion of adaptation into forest management planning and forest-related policies. The development strategy was to focus on a limited number of most relevant indicators and to build on existing capacity in order to produce information on current and future climate change impacts across Canada's vast forests. An initial list of 141 potential indicators relevant to forestry was compiled through a series of workshops with more than 100 researchers and forest sector stakeholders and through a global scan of climate change indicator initiatives. A rating system based on each indicator's potential relevance, sensitivity, and feasibility of measurement was used to select a subset of 35 indicators. These indicators fall within three broad systems—climate, forest, and human. Each indicator web page contains information on the relevance of the indicator, graphs, or maps on past trends and future projections across Canada and related links and references. This paper also presents lessons learned, discusses challenges and opportunities, and reviews potential next steps related to the broadening of this indicator system. [ABSTRACT FROM AUTHOR]

13C high resolution NMR (nuclear magnetic resonance) studies of solid neutral tetracyanoquinodimethane are performed using different polycrystalline samples: (i) natural isotopic abundance; (ii) 15N isotope enriched; (iii) 13C isotope selectively enriched on the CN groups; and (iv) 13C isotope selectively enriched on the first neighboring carbons of the CN groups. 14N quadrupole effects are observed on 13C spectra of the CN groups, and the quadrupole coupling constant for 14N is obtained: -3.84±0.12 MHz. The 13C isotropic chemical shifts are found: 112.6 ppm for CN groups; 90.8 ppm for the carbons directly bonded to these groups; 132.0 and 133.2 ppm for protonated carbons; and 151.7 ppm for the other carbons on the quinone ring. The principal components of the chemical shielding tensor, the shielding anisotropy, and the shielding asymmetry factor are also obtained for the 13C nuclei in the fragments C–(CN)2, by graphical analysis of CP/MAS spectra. The following values are obtained for 13C nuclei on CN groups: 211±11 ppm, -85±22 ppm (σ⊥ and σ||); -296±33 ppm (Δσ), and 0 (η). For the other carbon nuclei the values obtained for σ11, σ22, σ33, Δσ, and η are: 157±2 ppm, 75±2 ppm, 39±3 ppm, -77±4 ppm and 1.6±0.1, respectively. The reliability of these results is confirmed by a computer fit of the line intensities. [ABSTRACT FROM AUTHOR]

Electrochemical cells employing cis-rich polyacetylene as one electrode have been built in order to follow continuously in situ the evolution of its ESR characteristics during successive doping and undoping cycles. Very significant and almost reversible variations of the linewidth ΔHpp and asymmetry ratio A/B have been observed on either thin or thick samples. These variations are directly correlated with (i) the doping induced isomerization, (ii) the conductivity increase of the (CH)x film upon doping, and (iii) the sudden transition for the electronic spins system from a Curie-type behavior (degenerate semiconductor) to a Pauli-type one (metal). [ABSTRACT FROM AUTHOR]

Abstract: Background: Transitions out of hospital can influence recovery. Ideally, malnourished patients should be followed by someone with nutrition expertise, specifically a dietitian, post discharge from hospital. Predictors of dietetic care post discharge are currently unknown. The present study aimed to determine the patient factors independently associated with 30‐days post hospital discharge dietetic care for free‐living patients who transitioned to the community. Methodology: Nine hundred and twenty‐two medical or surgical adult patients were recruited in 16 acute care hospitals in eight Canadian provinces on admission. Eligible patients could speak English or French, provide their written consent, were anticipated to have a hospital stay of ≥2 days and were not considered palliative. Telephone interviews were completed with 747 (81%) participants using a standardised questionnaire to determine whether dietetic care occurred post discharge; 544 patients discharged to the community were included in the multivariate analyses, excluding those who were admitted to nursing homes or rehabilitation facilities. Covariates during and post hospitalisation were collected prospectively and used in logistic regression analyses to determine independent patient‐level predictors. Results: Dietetic care post discharge was reported by 61/544 (11%) of participants and was associated with severe malnutrition [Subjective Global Assessment category C: odd's ratio (OR) 2.43 (1.23–4.83)], weight loss post discharge [(OR 2.86 (1.45–5.62)], comorbidity [(OR 1.09 (1.02–1.17)] and a dietitian consultation on admission [(OR 3.41 (1.95–5.97)]. Conclusions: Dietetic care post discharge occurs in few patients, despite the known high prevalence of malnutrition on admission and discharge. Dietetic care in hospital was the most influential predictor of post‐hospital care. [ABSTRACT FROM AUTHOR]

Background/objectives: Little is known about factors associated with weight change post discharge from hospital; yet poor nutritional status in the transition from hospital to community can result in readmission. This exploratory study aimed to determine the factors associated with weight change 30 days post discharge defined as weight gain (WG; 5+ pounds), weight loss (WL; 5+pounds) or weight stable (WS).Subjects/methods: A total of 922 medical or surgical patients were recruited from 16 acute care hospitals in 8 Canadian provinces. Telephone interviews were completed with 747 (81%) participants 30 days post discharge using a standardized questionnaire that included: self-reported weight change, assessment of appetite, usage of healthcare services and supports for food-related activities of daily living. Covariates collected during hospitalization, including nutritional status at discharge evaluated by subjective global assessment (SGA), were used in logistic regressions.Results: Among the 747 patients, 26% reported WL, 16.7% had WG and 57.2% were WS. Those with WG were: younger (odds ratio (OR) 0.77 (0.69, 0.85)), male (OR 1.71 (1.12, 2.61)), malnourished at discharge (SGA B OR 2.13 (1.36, 3.33), SGA C OR 2.76 (1.19, 6.62)), and had a good appetite based on the low OR for fair/poor appetite (OR 0.28 (0.11, 0.66)). WL was associated with being on a special diet (OR 1.45 (1.07,1.96)) and reporting fair/poor appetite (OR 2.67 (1.76, 4.07)).Conclusions: Weight change was relatively common with WL predominating. Several variables were identified to be predictors of WL or weight gain, with appetite being common to both. Future work to further define and confirm these associations is warranted. [ABSTRACT FROM AUTHOR]

The United Nations Food and Agriculture Organization ( FAO) has been reporting country-level area in primary forests in its Global Forest Resource Assessment since 2005. The FAO definition of a primary forest (naturally regenerated forest of native species where there are no clearly visible indications of human activities and the ecological processes are not significantly disturbed) is generally accepted as authoritative and is being used in policy making. However, problems with this definition undermine our capacity to obtain globally coherent estimates. In addition, the current reporting on primary forests fails to consider the complementarily of non-primary forests toward the maintenance of ecosystem services. These issues undermine the appropriate tracking of changes in primary and non-primary forests, and the assessment of impacts of such changes on ecosystem services. We present the case for an operational reconsideration of the primary forest concept and discuss how alternatives or supplements might be developed. [ABSTRACT FROM AUTHOR]

Background Poor food intake is common in acute care patients and can exacerbate or develop into malnutrition, influencing both recovery and outcome. Yet, research on barriers and how they can be alleviated is lacking. The present study aimed to (i) describe the prevalence of food intake barriers in diverse hospitals and (ii) determine whether patient, care or hospital characteristics are associated with the experience of these barriers. Methods Patients ( n = 890; 87%) completed a validated questionnaire on barriers to food intake, including perceptions of food quality, just before their discharge from a medical or surgical unit in each of 18 hospitals across Canada. Scores were created for barrier domains. Associations between these barriers and selected patient characteristics collected at admission or throughout the hospital stay and site characteristics were determined using bivariate analyses. Results Common barriers were being interrupted at meals (41.8%), not being given food when a meal was missed (69.2%), not wanting ordered food (58%), loss of appetite (63.9%) and feeling too sick (42.7%) or tired (41.1%) to eat. Younger patients were more likely ( P < 0.0001) to report being disturbed at meals (44.6%) than older patients (33.9%) and missing a meal for tests (39.0% versus 31.0%, P < 0.05). Patients who were malnourished, women, those with more comorbidity, and those who ate <50% of the meal reported several barriers across domains. Conclusions The present study confirms that barriers to food intake are common in acute care hospitals. This analysis also identifies that specific patient subgroups are more likely to experience food intake barriers. Because self-reported low food intake in hospital was associated with several barriers, it is relevant to consider assessing, intervening and monitoring barriers to food intake during the hospital stay. [ABSTRACT FROM AUTHOR]

Background/Objectives:Nutrition screening should be initiated on hospital admission by non-dietitians. This research aimed to validate and assess the reliability of the Canadian Nutrition Screening Tool (CNST) in the 'real-world' hospital setting.Subjects/Methods:Adult patients were admitted to surgical and medical wards only (no palliative patients). Study 1-Nutrition Care in Canadian Hospitals (n=1014): development of the CNST (3 items: weight loss, decrease food intake, body mass index (BMI)) and exploratory assessment of its criterion and predictive validity. Study 2-Inter-rater reliability and criterion validity assessment of the tool completed by untrained nursing personnel or diet technician (DT) (n=150). Subjective Global Assessment performed by site coordinators was used as a gold standard for comparison.Results:Study 1: The CNST completed by site coordinators showed good sensitivity (91.7%) and specificity (74.8%). Study 2: In the subsample of untrained personnel (160 nurses; one DT), tool's reliability was excellent (Kappa=0.88), sensitivity was good (>90%) but specificity was low (47.8%). However, using a two-item ('yes' on both weight change and food intake) version of the tool improved the specificity (85.9%). BMI was thus removed to promote feasibility. The final two-item tool (study 1 sample) has a good predictive validity: length of stay (P<0.001), 30-day readmission (P=0.02; X2 5.92) and mortality (P<0.001).Conclusions:The simple and reliable CNST shows good sensitivity and specificity and significantly predicts adverse outcomes. Completion by several untrained nursing personnel confirms its utility in the nursing admission assessment. [ABSTRACT FROM AUTHOR]

Background Malnutrition is common in acute care hospitals worldwide and nutritional status can deteriorate during hospitalisation. The aim of the present qualitative study was to identify enablers and challenges and, specifically, the activities, processes and resources, from the perspective of nutrition care personnel, required to provide quality nutrition care. Methods Eight hospitals participating in the Nutrition Care in Canadian Hospitals study provided focus group data ( n = 8 focus groups; 91 participants; dietitians, dietetic interns, diet technicians and menu clerks), which were analysed thematically. Results Five themes emerged from the data: (i) developing a nutrition culture, where nutrition practice is considered important to recovery of patients and teams work together to achieve nutrition goals; (ii) using effective tools, such as screening, evidence-based protocols, quality, timely and accurate patient information, and appropriate and quality food; (iii) creating effective systems to support delivery of care, such as communications, food production and delivery; (iv) being responsive to care needs, via flexible food systems, appropriate menus and meal supplements, up to date clinical care and including patient and family in the care processes; and (v) uniting the right person with the right task, by delineating roles, training staff, providing sufficient time to undertake these important tasks and holding staff accountable for their care. Conclusions The findings of the present study are consistent with other work and provide guidance towards improving the nutrition culture in hospitals. Further empirical work on how to support successful implementation of nutrition care processes is needed. [ABSTRACT FROM AUTHOR]

In spite of the many factors that are occurring and known for positively affecting the growth of forests, some boreal forests across North America have recently felt the adverse impacts of environmental changes. Knowledge of causes for productivity declines in North American boreal forests remains limited, and this is owed to the large spatial and temporal scales involved, and the many plant processes affected. Here, the response of pristine eastern boreal North American (PEBNA) forests to ongoing climatic changes is examined using in situ data, community ecology statistics, and species-specific model simulations of carbon exchanges forced by contemporary climatic data. To examine trends in forest growth, we used a recently acquired collection of tree-ring width data from 252 sample plots distributed in PEBNA forests dominated by black spruce (Picea mariana [Mill.] B.S.P.) and jack pine (Pinus banksiana Lamb.). Results of linear trend analysis on the tree growth data highlight a dominating forest growth decline in overmature forests (age > 120 years) from 1950 to 2005. In contrast, improving growth conditions are seen in jack pine and mature (70-120 years) black spruce stands. Multivariate analysis of climate and growth relationships suggests that responses of PEBNA forests to climate are dependent on demographic and species traits via their mediation of temperature and water stress constraints. In support of this hypothesis, the simulation experiment suggests that in old-growth black spruce stands the benefit to growth brought on by a longer growing season may have been low in comparison with the increasing moisture stress and respiration losses caused by warmer summer temperatures. Predicted increases in wildfire frequency in PEBNA forests will likely enhance the positive response of landscape-level forest growth to climate change by shifting the forest distribution to younger age classes while also enhancing the jack pine component. [ABSTRACT FROM AUTHOR]

In spite of the many factors that are occurring and known for positively affecting the growth of forests, some boreal forests across North America have recently felt the adverse impacts of environmental changes. Knowledge of causes for productivity declines in North American boreal forests remains limited and this is owed to the large spatial and temporal scales involved, and the many plant processes affected. Here, the response of pristine eastern boreal North American (PEBNA) forests to ongoing climatic changes is examined using in situ data, community ecology statistics, and species-specific model simulations of carbon exchanges forced by contemporary cli matic data. To examine trends in forest growth, we used a recently acquired collection of tree-ring width data from 252 sample plots distributed in PEBNA forests dominated by black spruce (Picea mariana [Mill.] B.S.P.) and jack pine (Pinus banksiana Lamb.). Results of linear trend analysis on the tree growth data highlight a dominating forest growth decline in overmature forests (age > 120 yr) from 1950 to 2005. In contrast, improving growth conditions are seen in jack pine and mature (70-120 yr) black spruce stands. Multivariate analysis of climate and growth relationships suggests that responses of PEBNA forests to climate are dependent on demographic and species traits via their mediation of temperature and water stress constraints. In support of this hypothesis, the simulation experiment suggests that in old-growth black spruce stands the benefit to growth brought on by a longer growing season may have been low in comparison with the increasing moisture stress and respiration losses caused by warmer summer temperatures. Predicted increases in wildfire frequency in PEBNA forests will likely enhance the positive response of landscape-level forest growth to climate change by shifting the forest distribution to younger age classes while also enhancing the jack pine component. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)