bluuebunny/crossref_metadata_2025 huggingface dataset:
Injuries and wounds in elderly living in poverty conditions in Mexico
Authors: Rojo M Ma Tllez , Manrique-Espinoza B , Salinas-Rodrguez A , Campuzano J
Published: March 2011

Objective

To estimate the prevalence of injuries and wounds of Mexican elderly living in poverty conditions.

Methods and Materials

A three stages probabilistic survey, stratified by community type (rural or urban) and nationally representative was conducted. The objective population was formed by individuals with 70 years old and more, who are beneficiaries from Oportunidades program.

Results

Interviewed people average age was 78.4 years, and 56.5% were women. 61.2% of elderly are illiterate. 11% of women and 10% of men reported had suffered some injury or cut within the last 12 months. The highest proportion of reported injuries were on arms and hands (47%), followed by legs and feet (39%). 66% of these accidents happened in the elderly home, while 15% happened in a public place. Regarding burns, women presented a proportion higher than men. (3.4% vs 0.8%, respectively); burns were more frequent on arms and hands (68%). 96% happened inside the elderly home. Nevertheless, it is observed an important prevalence of elderly reporting that these accidents happened intentionally, 4% in those who suffered injuries or cuts, and 9% in those reporting some burn.

Conclusion

The necessity of attention and specific interventions related to injuries and wounds of our study population, due to the vulnerability conditions, incapacity and dependency that they live in, is shown.
Safety culture in the construction industry. The reality beyond working safely
Authors: Arendsz G , Hudson P
Published: March 2011

The aim of this study was to determine to what extent the Safety Culture on a construction worksite could be understood using an ethno methodological approach. The number of incidents in construction is high compared to other industries; in order to prevent incidents it is essential to discover the factors influencing safety. In this study talks and walks were performed on the worksite with different employees. The results suggest that on the worksite more than one type of safety culture exist. One of the main factors influencing attitudes and behaviours of the general foremen was no solutions to problems. This and some other factors are part of the pattern that makes up the type of safety culture(s). Factors that identify a culture of reluctance are presented in a model. The possibility of improving the performance and the culture by improving interventions that actually solve safety problems is discussed.
Safeguarding women and children from abuse
Authors: Browne K , Butchart A , Penhale B , Phillips C , Harwin N
Published: March 2011

Preventing violence to women and children in the home; a review of the literature/Interventions to support victims of domestic violence: The ‘Safety in numbers’ project/Preventing sexual violence to young women and children/Evidence based policy and interventions to support adult victims of sexual violence/Harmful traditional practices and their impact on health and social services in the UK.
An analysis of safe driving using concurrent tasks: effects of making decisions from the traffic sign information and performing verbal versus spatial-imagery tasks
Authors: Moreno-Ríos S
Published: March 2011

Driving requires performing different subtasks concurrently that can interfere. Specifically, two driving sub-tasks are analysed in this work: Participants judge manoeuvres regulated by traffic signs (turn left or turn right mandatory and prohibitory signs) that can be made by a vehicle at an intersection (a T-junction). Every traffic sign conveys a single proposition about traffic conditions. Drivers must integrate this proposition with their own goals and other known facts to decide on an appropriate action in what amounts to a deduction task. This study analyses how people decide whether a situation is allowed or not, taking into account the information provided by one sign – mandatory or prohibitory signs. Results showed that people integrate two obligatory sign messages – informing where one can go – more easily than two prohibitory sign messages – informing where not to go. Therefore, it could be said that each traffic sign elicits an internal mental model elaboration in which forbidden actions are explicitly labelled by means of attached “mental footnotes” indicating the epistemic status of “prohibitory information.” In addition, the participants performed two types of mental tasks, one verbal and the other involving spatial-imagery. Given the visual and spatial character of information acquisition while driving, and the role that spatial codes play on the generation of ‘mental footnotes’ we expected task behaviour to be more disrupted by performing concurrent tasks that require visual imagery or spatial resources than by performing verbal tasks. Results from the proposed hypothesis are discussed and conclusions for safety driving are made.
Impact and lessons learned from the first 5 years of the Child Safety Action Plan (CSAP) initiative in 26 countries in Europe
Authors: MacKay M , Vincenten J
Published: March 2011

CSAP is a European initiative whose aim is to raise awareness of injury as the leading cause of death for children in Member States and increase commitment to the issue through the development of evidence-based government endorsed national child safety action plans. To support development of plans and increased capacity to support implementation, three main areas of activity have been undertaken: (1) development and public release of Child Safety Report Cards and profiles based on standardised indicators, (2) activities to encourage adoption, implementation and monitoring of evidence-based good practices and (3) activities to support Child Safety Action Plan development. Information on the impact and lessons learned to date have been collected and validated using various methods including analysis of country progress updates, specific reflection sessions and questionnaires. Impacts to date include national child safety action plans in nine countries where none existed previously, new or stronger links with government and between national partners, increased awareness of child injury issue and increased capacity to take action, increased multi-sectoral cooperation, collaboration and enhanced political commitment to the issue, and demonstrated value of report card indicators used in benchmarking progress. Lessons learned include the importance of: leadership and commitment, early and continued involvement of the right people, having good tools and resources to work with, public benchmarking of performance and progress and linking into existing political commitments. The Child Safety Action Plan provides a model for other areas of injury to consider for enabling a coordinated and comprehensive approach to injury reduction efforts.
Preventing violence to women and children in the home: an overview
Authors: Browne K , Jackson V
Published: March 2011

It has been estimated that 4 to 16% of children are physically abused and 1 in 10 are neglected or psychologically abused, the vast majority of the time by their parents and caregivers. Disabled children are 3.8 times more likely to be physically abused than non-disabled children. The need for prevention is exemplified by a survey of young people resident in secure accommodation which shows that 4 out of 5 young offenders had adverse childhood experiences. Furthermore, it has been found that 75% of adolescents and teenagers running away from home report physical and sexual abuse as the primary reason. Hence, there is an apparent need to refocus efforts to safeguard children. This might tackle an over-reliance on social services as the lead agency for child care and protection and give more responsibility to the health sector for the prevention of child maltreatment through a public health approach, with home visitation programmes being most effective. This would provide support services to children and families in need at different stages in the child's development. Findings from a systematic review of interventions with children and their non-abusing mothers found that these interventions were effective in reducing child behaviour problems and mother's stress and PTSD symptoms. It was noted that one third of local authorities in the UK have no specialist service for dealing with domestic violence. Despite the recognition of the significant harm caused by domestic violence on children and relative risk of abuse being 23 times higher than other families, this has not led to an increase in the provision of services for children. Services for women and girls from black and ethnic minority backgrounds are even more limited. Often, both the perpetrators and the victims from all backgrounds join a waiting list for intervention and treatment concerning violence, mental health problems and therapy. Meanwhile the children remain in foster care awaiting the outcome of care proceedings with no permanent placement.
Preventing sexual violence to young women and children
Authors: Proops R , Rees D
Published: March 2011

Sexual violence against children represents a major public health and social welfare problem within UK society affecting 16% of under 16s to 2m children and young people. It is under identified and under reported. Better understanding of the impact on individuals and families by commissioners, health and social care providers only goes part way to resolving the current problems. It is only by recognising the range of presentations, symptoms and the variety of settings in which the presence and impact of sexual violence might reveal itself that statutory and voluntary services can hope to respond appropriately to the needs of individuals. It is the responsibility of individual professionals and local services to ensure that the individual needs of people are met at the right time, by the right people, in the most sensitive way. This paper uses recent evidence relating to prevalence, incidence and the impact of sexual violence against children. In particular it identifies the ways in which the NHS can effectively respond to the physical and psychological needs of children young people and their families to ensure that health services are age appropriate, timely, provided in an environment which is supportive and by knowledgeable staff.
Predicting and preventing youth violence: understanding and disrupting developmental trajectories and risk
Authors: Dahlberg L
Published: March 2011

The relationship between age and crime is well known and has been documented throughout history. Although different types of offenses tend to peak at different ages, violent and delinquent behaviour typically increase during adolescence and the early years of adulthood, and taper off with advancing age. There also appears to be little specialisation in the types of offenses committed by young people. Young people generally commit a variety of violent and non-violent offenses. In recent years, researchers have begun to explore whether violent and delinquent behaviour in adolescence and young adulthood is part of a general pattern of antisocial and aggressive behaviour that emerges during childhood or whether it is the result of certain personal, situational and environmental factors. Some children, for example, exhibit stubborn, defiant, and disobedient behaviour at very young ages, and progress to mild and eventually more severe forms of aggressive and delinquent behaviour by adolescence and young adulthood. Other children either do not exhibit serious problem behaviour until they reach adolescence or seem to outgrow aggressive behaviour by the time they enter primary school. For violence prevention purposes, it is important to know the extent to which patterns of aggressive and antisocial behaviour in childhood are predictive of violent and delinquent behaviour at later ages and also to know which factors increase or buffer the risk for violent and delinquent behaviours at different ages. Understanding this continuity or change in behaviour during different developmental periods is important for identifying appropriate points for intervention. The purpose of this presentation is, thus, threefold: (1) to describe the developmental pathways of aggressive, violent and delinquent behaviour, (2) to describe the factors that increase or buffer against the risk for violent and delinquent behaviour at different ages and across developmental periods and (3) to discuss the implications of the different patterns of behaviour and risk for designing preventive interventions.
Evaluation considerations: measures and methods
Authors: Bangdiwala S I
Published: March 2011

There is a pressing need to effectively evaluate safety promotion actions worldwide, to inform the skeptics and funders about the real impact of injuries on societies in hindering their development, and the potential societal cost-benefits of the multiple activities and actions being carried out. The evaluation of programmatic or structural interventions for injury prevention or control is a complex activity. It can be carried out at different levels – the various components of a program or a program as a whole; in individuals in a specific community or a region, or at the community or regional level. There are multiple aspects of effectiveness, from process indicators, impact and outcome measures, to health related or financial considerations. Indicators can be quantified with different measures, and these in turn can be obtained through various types of experimental study designs. Of particular note is that most interventions tend to be carried out in community settings, and this impacts the choice of measures and study designs that are methodologically feasible and practical to be used. Process evaluation addresses the various aspects of the implementation of an intervention, and how well they worked. Impact evaluation, on the other hand, assesses changes in knowledge, attitudes, beliefs, behaviours and practices. The more commonly known measures are the outcome measures, since they address changes in behaviours directly related to injury events, injury events themselves (eg, frequency, type and pattern), morbidity and mortality. These measures are meaningful insofar as the study design used is appropriate. From a methodological perspective, sound evidence comes from controlled randomised experimental designs. Thus, experimental study designs such as randomised controlled trials, grouped randomised experiments, and community-randomised studies are judged as ‘better’ than quasi-experimental study designs such as non-randomised comparative studies, before-after studies, and observational studies like cohort studies, case–control studies and comparative cross-sectional studies. In this presentation, we review the various measures typically used and the most common types of study designs that provide statistical evidence on effectiveness. We contrast and compare the methodological advantages and limitations of the various choices. We also discuss incorporating ‘qualitative evidence’ to complement the quantitative indicators, as well as the consideration of economic indicators of effectiveness, such as disability adjusted life years (DALYs) or quality adjusted life years (QALYs). The challenge to us as active researchers in the injury control and safety promotion field is to develop convincing collective evidence of what aspects and what interventions work, and help reduce the societal burden from unnecessary injuries.
The Child Safety Education Coalition (CSEC) and its use of practical safety education to reduce injury rates
Authors: Taylor E
Published: March 2011

Unintentional injury is a leading cause of death and illness among children aged 1–14 years, and causes more children to be admitted to hospital each year than any other reason. It kills at the same rate as cancer. Risk literacy – an understanding of relative risk and risk management strategies – within the population is poor and yet this is vital for preventing unintentional injury. To address this issue, RoSPA set up CSEC with support for the Department for Education. The aim of CSEC was to research, develop, pilot and roll-out effective new forms of Practical Safety Education (PSE) which would give children and young people the knowledge and skills that would allow them to manage everyday risks and hazards. These new forms of PSE are designed to be co-incidental – children and young people develop their safety awareness while doing chosen activities. CSEC now has over 100 member organisations and is developing a library of proven management tools, training sessions, online tools and leading edge research. Widespread adoption of these outputs should improve risk literacy and the eventual outcome of a reduced rate of unintended injuries.
Diabetes in pregnancy: health risks and management
Authors: Ali Sarah , Dornhorst Anne
Published: March 2011

Diabetes in pregnancy is increasing and therefore it is important to raise awareness of the associated health risks to the mother, the growing fetus, and the future child. Perinatal mortality and morbidity is increased in diabetic pregnancies through increased stillbirths and congenital malformation rates. These are mainly the result of early fetal exposure to maternal hyperglycaemia. In the mother, pregnancy may lead to worsening or development of diabetic complications such as retinopathy, nephropathy, and hypoglycaemia. This review defines pregestational and gestational diabetes and the associated health risks to the growing fetus and mother. Management is discussed, focusing on clinical evidence based guidelines published by the American Diabetic Association and the UK National Institute for Health and Clinical Excellence on the management of pregnant women with pre-existing diabetes.
ArabidopsisAt2g40730 encodes a cytoplasmic protein involved in nuclear tRNA export
Authors: Johnstone Aaron D. , Mullen Robert T. , Mangroo Dev
Published: March 2011

Nuclear tRNA export plays an essential role in several key cellular processes, such as regulation of protein synthesis, cell cycle progression, response to nutrient availability and DNA damage, and development. While the overall mechanism of nuclear tRNA export is, in general, poorly understood, the details of specific steps are emerging from studies conducted in different organisms aimed at identifying and characterizing components involved in the process. Here, we report that Arabidopsis thaliana (L.) Heynh At2g40730 encodes CTEXP, a cytoplasmic protein component of the nuclear tRNA export process. CTEXP bound tRNA directly and saturably, and like the nuclear tRNA export receptor PAUSED, overexpression of CTEXP restored export of a nuclear export-defective lysine amber suppressor tRNA in tobacco cells. CTEXP was also found to associate with nucleoporins of the nuclear pore complex (NPC), PAUSED, and the GTPase Ran in vivo. CTEXP interacted directly with PAUSED in vitro and RanGTP, but not RanGDP. Furthermore, a portion of CTEXP appeared to associate with the NPC. Taken together, the data suggest that CTEXP assists with unloading of tRNAs from PAUSED at the cytoplasmic side of the NPC in plant cells.
Diversity of macromycetes determined by tree species, vegetation structure, and microenvironment in tropical cloud forests in Veracruz, Mexico
Authors: Gómez-Hernández Marko , Williams-Linera Guadalupe
Published: March 2011

Tropical montane cloud forests (TMCFs) have high levels of plant and fungal diversity. We examined whether macromycete alpha and beta diversity were associated with woody plant diversity, forest structure, or microclimate, in four TMCFs at lower (1240–1440 m) and upper altitudes (1790–1900 m) in Veracruz, Mexico. Every 2 weeks during the growing season, macromycetes were collected from ten 10 m × 10 m permanent plots per site, and air and soil temperature and humidity were measured. In total, 2059 macromycetes (509 species) and 678 woody plants (63 species) were recorded. Macromycete diversity (Shannon Index) values of the two sites located in lower forests were higher than in upper sites. Beta diversity (Jaccard index) indicated high turnover among sites and sampling times. Macromycete richness was negatively correlated with overstorey tree richness, understorey vegetation structure, and air temperature, but was positively correlated with air humidity and soil water content and altitude. Ordinations separated lower from upper altitude forest sites. Changes in composition and abundance of macromycete species with altitude were explained by precipitation, temperature, and understorey vegetation structure, while soil water content effect changes within a growing season. Results imply that understorey vegetation structure is a more important aspect for macrofungal diversity management than for woody plant diversity.
Contrasting climate- and land-use-driven tree encroachment patterns of subarctic tundra in northern Norway and the Kola PeninsulaThis article is a contribution to the series Tree recruitment, growth, and distribution at the circumpolar forest–tundra transition.
Authors: Aune Sigrun , Hofgaard Annika , Söderström Lars
Published: March 2011

High-latitude regions are experiencing substantial climate change, and the forest–tundra transition is assumed to sensitively track these changes through advancing treeline and increased tundra encroachment. However, herbivores may influence these responses. The present study addresses, through analyses of age structures, growth characteristics, and climate correspondence, how mountain birch (Betula pubescens Ehrh. ssp. czerepanovii (Orlova) Hämet-Ahti) treelines and sapling cohorts beyond the treeline have responded to the last decade’s warming in six North European subarctic areas with different climate and grazing characters. The results show different response patterns among areas representing advancing, stationary, and possibly retreating treelines. Recruitment was abundant over the last decades in all areas except one, with predominantly arctic conditions, where both tree and sapling cohorts were old. Areas with high annual precipitation show advancing birch populations characterized by young individuals and partly overlapping tree and sapling age distributions. Areas in reindeer herding districts show stationary or retreating birch populations characterized by nonoverlapping age distributions and low sapling survival. Recruitment patterns beyond the treeline generally corresponded with non-growing-season climate variables, mainly precipitation, indicating the importance of a protecting snow cover. The results highlight the important interplay between abiotic and biotic control over tundra encroachment and treeline dynamics and the importance of multisite studies when addressing responses to warming.
Dendroclimatic relationships and possible implications for mountain birch and Scots pine at treeline in northern Sweden through the 21st centuryThis article is a contribution to the series Tree recruitment, growth, and distribution at the circumpolar forest–tundra transition.
Authors: Young Amanda B. , Cairns David M. , Lafon Charles W. , Moen Jon , Martin Laura E.
Published: March 2011

Changing climate in the Arctic is expected to have significant effects on the pattern and distribution of terrestrial vegetation. Species characteristic of specific zones in the mountains of northern Sweden have been shown to migrate up- and down-slope with changes in climate over the Holocene. This study evaluates the potential for Scots pine (Pinus sylvestris L.) to become a treeline dominant at Fennoscandian treelines, replacing mountain birch (Betula pubescens subsp. czerepanovii (Orlova) Hämet-Ahti). Data from paired mountain birch and Scots pine tree-ring chronologies for eight locations in northern Sweden are used to develop climate – tree ring width index (RWI) relationships. Modeled climate–RWI relationships are then used to predict the relative RWI values of the two species under a suite of climate-forcing scenarios using an ensemble of three global climate models. Results indicate that mountain birch and Scots pine RWI are both correlated with summer temperatures, but Scots pine is more likely than mountain birch to be influenced by moisture conditions. Predictions of RWI under future climate conditions indicate that mountain birch is unlikely to be replaced by Scots pine within the next century.
Black spruce regeneration at the treeline ecotone: synergistic impacts of climate change and caribou activityThis article is a contribution to the series Tree recruitment, growth, and distribution at the circumpolar forest–tundra transition.
Authors: Tremblay Geneviève Dufour , Boudreau Stéphane
Published: March 2011

Tree regeneration at treeline is often inhibited by harsh climatic conditions and ecological constraints such as the presence of a continuous lichen cover. The objective of this study was to verify if recent climate warming and increased caribou (Rangifer tarandus L.) activity, which destroys the lichen cover, could act synergistically to increase black spruce (Picea mariana (Mill.) B.S.P.) regeneration. We collected cones produced in 2006–2007 to compare seed viability with data from 1989 to 1995. We conducted experimental plantations (field and controlled conditions) to determine if germination and seedling emergence were higher in disturbed environments where mineral soil was exposed. We sampled naturally established seedlings to evaluate the relationship between the year of establishment and caribou activity and to compare growth in disturbed and undisturbed environments. We found that seed viability was significantly higher in 2006–2007 compared with 1989–1995. The number of germinated seeds per cone increased by a factor >1000. Germination and seedling establishment were higher in the disturbed environment (mineral soil). Finally, although seedling establishment in areas with continuous lichen cover was rather constant over the last 50 years, 73.5% of the seedlings recorded on bare mineral soil became established in the years following high caribou activity. Our results suggest that climate warming and caribou activity are likely to act synergistically to promote black spruce regeneration at treeline.
Dendroclimatic response of a coastal alpine treeline ecotone: a multispecies perspective from LabradorThis article is a contribution to the series Tree recruitment, growth, and distribution at the circumpolar forest–tundra transition.
Authors: Trindade M. , Bell T. , Laroque C. P. , Jacobs J. D. , Hermanutz L.
Published: March 2011

Coastal alpine forests are highly vulnerable to oceanic climate trends, yet these diverse environmental interactions remain poorly understood. We used a multispecies perspective to try to better assess the radial growth response of alpine treeline species within the Northeast Atlantic region of North America to climate variables using bootstrapped correlation analysis. The four species present, black spruce (Picea mariana (Mill.) B.S.P.), white spruce (Picea glauca (Moench) Voss), balsam fir (Abies balsamea (L.) Mill.), and eastern larch (Larix laricina (Du Roi) K. Koch) were sampled in an effort to capture tree–climate sensitivity that is representative of this entire alpine treeline. The climate–growth relationships of spruce trees were comparable with those reported in other Labrador studies, but spring drought sensitivity as reported for coastal northern white spruce trees was not observed. Rather, high levels of precipitation suggest that drought did not limit the radial growth of any of the four species. The relatively small number of statistically significant correlations between monthly climate variables and fir and larch trees suggests that factors other than climate limit their radial growth. The multispecies approach better highlighted the range of species-specific relationships between alpine treeline forests and maritime climates (monthly temperature and precipitation) found at the treeline ecotone.
Stable isotope tracing of fertilizer sulphur uptake by lodgepole pine: foliar responses
Authors: Sanborn P. T. , Brockley R. P. , Mayer B.
Published: March 2011

A plot-scale fertilizer sulphur (S) stable isotope tracer study was established in 2001 in the Sub-Boreal Spruce biogeoclimatic zone in central interior British Columbia where S deficiencies are common in lodgepole pine ( Pinus contorta var. latifolia Engelm. ex S. Wats.) stands. Treatments used operationally realistic applications of 300 kg N·ha–1 as urea and 100 kg S·ha–1 as either sulphate (SO4) or elemental S (S0). δ34S values of fertilizer S differed by >9‰ from pretreatment δ34S values of total S in foliage at the two study sites (5.2‰ and 8.2‰). These differences enabled quantification of fertilizer uptake using isotopic analysis of post-treatment foliar S. Addition of K2SO4 with δ34S of +17.5‰ increased foliar δ34S by 3.5‰ and 6.6‰ at the two sites, respectively, in the year after treatment, indicating fertilizer contributions >40% to foliar total S. For a S0 fertilizer application with a δ34S value of +19.3‰, foliar δ34S increases were smaller but steadily increased, resulting in an average tracer S uptake of ~20% over three years. These results confirmed the more rapid availability of S from SO4-based fertilizers and demonstrated the feasibility of field tracer experiments using stable S isotopes at natural abundance levels.
Physiological responses of Abies faxoniana seedlings to different non-growing-season temperatures as revealed by reciprocal transplantations at two contrasting altitudes
Authors: Wu Chengchun , Peng Guoquan , Zhang Yuanbin , Xu Xiao , Korpelainen Helena , Berninger Frank , Li Chunyang
Published: March 2011

Detailed information on plants’ responses to varying temperature conditions will be useful when assessing the potential effects of climate change. We conducted reciprocal transplantations in Abies faxoniana Rehd. et Wils. to detect responses of seedlings to different winter (non-growing-season) temperatures in the Wanglang National Nature Reserve, China. Winter temperature variation might alter nitrogen allocation between 1-year-old leaves and branchlets. In leaves, coupling acclimation between photosynthesis potential (evident in pigment content and composition and carbon isotope composition (δ13C)) and adversity tolerance (detectable in peroxidase activity, malondialdehyde content, and nonstructural carbohydrate composition) to winter temperature variation was documented, whereas in branchlets, warming winter did not result in a δ13C-discriminative respiration process at tissue level. Although the experiment included only a short winter period, warming winter was found to pose a negative influence (decreased storage and increased leaf thickness) on A. faxoniana seedlings of subalpine forest understory. As both genetic adaptation and phenotypic plasticity could be responsible for such physiological variation, a detailed altitudinal investigation and a long-term experiment on A. faxoniana seedlings are needed to properly assess their responses to climate change.
Effects of needleleaf forest cover on radiation and snowmelt dynamics in the Canadian Rocky Mountains
Authors: Ellis C. R. , Pomeroy J. W. , Essery R. L.H. , Link T. E.
Published: March 2011

Radiation is the main energy source for snowpack warming and melt in mountain needleleaf forests, and runoff from these forests is the main contributor to spring river flows in western North America. Utilizing extensive field observations, the effect of needleleaf forest cover on radiation and snowmelt timing was quantified at pine and spruce forest sites and nearby clearings of varying slope and aspect in an eastern Canadian Rocky Mountain headwater basin. Compared with open clearing sites, shortwave radiation was much reduced under forest cover, resulting in smaller differences in melt timing between forested slopes relative to open slopes with different aspects. In contrast, longwave radiation to snow was substantially enhanced under forest cover, especially at the dense spruce forest sites where longwave radiation dominated total energy for snowmelt. In both pine and spruce environments, forest cover acted to substantially reduce total radiation to snow and delay snowmelt timing on south-facing slopes while increasing total radiation and advancing snowmelt timing on north-facing slopes. Results strongly suggest that impacts on radiation to snow and snowmelt timing from changes in mountain forest cover will depend much on the slope and aspect at which changes occur.
Conserving the diversity of Ontario tree species under multiple uncertain climatic futures
Authors: Crowe Kevin A. , Parker William H.
Published: March 2011

In an environment of uncertain climatic change, there is an urgent need to develop robust reserve networks, i.e., networks that conserve species across multiple climatic futures. Using climatic envelopes based on multiple future climatic scenarios, we first estimate the impacts that these scenarios might have on the distributions of 63 native tree species in the Province of Ontario. Next, an optimization model is applied to expand an existing system of reserves in this province by determining the minimum number of optimal locations for additional reserves both with and without the need for migration. The optimization model formulated differs from previous work in that it meets the need for present and future distributions to occur in the same reserve and accommodates multiple differing climate change scenarios rather than a single scenario. The reserve selection approach described here can be applied anywhere that species’ distributions and environmental grids are available. Although this approach is designed to produce a robust solution to the uncertainties over future climatic scenarios, it does not eliminate these uncertainties because the proposed solutions inherit the uncertainties of the global climate change models.
Assessing terrestrial lichen biomass using ecoforest maps: a suitable approach to plan conservation areas for forest-dwelling caribou
Authors: Lesmerises Rémi , Ouellet Jean-Pierre , St-Laurent Martin-Hugues
Published: March 2011

Terrestrial lichens are an important part of the winter diet of forest-dwelling caribou ( Rangifer tarandus caribou (Gmelin, 1788)), and developing forest management guidelines to support high lichen biomass could enhance both individual- and population-level health of this threatened species. Our objective was to develop an index to assess terrestrial lichen biomass available to caribou at the landscape scale using ecoforest maps based on forest characteristics (age, density, and height) and geographical variables (slope, altitude, and latitude). We sampled 439 sites within 8340 km2 of the spruce–moss domain located >100 km north of the Saguenay River (Quebec, Canada). Since they are known to support terrestrial lichen, we sampled only spruce-dominated stands older than 50 years, representing 41.8% of the study area. Using a two-step approach, we first modeled lichen occurrence and thereafter lichen biomass in sites where lichens were found. Lichen occurrence was positively correlated with latitude but negatively with stand age, height, and density. Lichen biomass was primarily a function of altitude and tree density. Using this index could prioritize conservation of areas that are most likely to contain high lichen biomass, thus favoring caribou population maintenance in logged landscapes.
Long-term effects of weed control and fertilization on the carbon and nitrogen pools of a slash and loblolly pine forest in north-central Florida
Authors: Vogel Jason G. , Suau Luis J. , Martin Timothy A. , Jokela Eric J.
Published: March 2011

The effects of fertilization, weed control, and fertilization plus weed control on vegetation and soil C and N pools were examined for a loblolly pine ( Pinus taeda L.) and slash pine ( Pinus elliottii var. elliottii Engelm.) forest at ages 18 and 26 years (at the end of rotation). The total C accumulated in fertilized forests without weed control was 20% (slash pine) and 40% (loblolly pine) greater than in the control forests at the end of rotation. Weed control increased pine C pools at 18 years, but by the end of rotation, weed control effectively resulted in no gain in ecosystem C. When the two treatments were combined, weed control slightly subtracted from the net C benefit produced by fertilization. This result occurred because of decreased forest floor and soil C in the weed control plots. Fertilization significantly increased stem, foliage, forest floor, and soil N pools, and N retention was 63% and 103% of the applied N in the slash and loblolly pine forests, respectively. Weed control with fertilization reduced ecosystem N retention efficiency, but weed control alone did not negatively affect ecosystem N accumulation. These results suggest that the optimal treatment for increasing C accumulation and N retention in these ecosystems is fertilization without weed control.
Reply to comment by Messier et al. on “Present-day expansion of American beech in northeastern hardwood forests: Does soil base status matter?”Appears in Can. J. For. Res. 39: 2273–2282 (2009).
Authors: Duchesne Louis , Ouimet Rock
Published: March 2011

We respond to the comment by Messier et al. (2011. Can. J. For. Res. 41: 649–653) on our recent paper questioning the possible influence of the base status of soils in the present-day expansion of American beech ( Fagus grandifolia Ehrh.) in Quebec (2009. Can. J. For. Res. 39: 2273–2282). From our observations, as well as from a large body of scientific evidence reporting on the high sensitivity of sugar maple ( Acer saccharum Marsh.) to the acid–base status of soils, we hypothesized that soil base cation depletion, caused in part by atmospheric deposition, is among the main factors involved in the present-day expansion of American beech over large areas in Quebec. Clearly, we suggested in our paper that acid deposition might act with other factors to explain the expansion of American beech. In this context, our conclusions are far from any oversimplified explanation, as stated by Messier et al., but rather, they point out a level of complexity above the one currently discussed.
SYMMETRIC BIFURCATIONS IN A RING OF COUPLED DIFFERENTIAL EQUATION WITH PIECEWISE CONTINUOUS ARGUMENTS
Authors: ZHENG BAODONG , MA JIAN , ZHENG HUIFENG , ZHANG CHUNRUI
Published: March 2011

Symmetry bifurcations of equilibrium points of three coupled differential equation with piecewise continuous arguments (EPCA) oscillators are studied. The system is equivariant under dihedral group D3 with order 6. This causes several types of symmetrical bifurcations.
PREDICTING CLIMATE TIPPING AS A NOISY BIFURCATION: A REVIEW
Authors: THOMPSON J. MICHAEL T. , SIEBER JAN
Published: March 2011

There is currently much interest in examining climatic tipping points, to see if it is feasible to predict them in advance. Using techniques from bifurcation theory, recent work looks for a slowing down of the intrinsic transient responses, which is predicted to occur before an instability is encountered. This is done, for example, by determining the short-term autocorrelation coefficient ARC(1) in a sliding window of the time-series: this stability coefficient should increase to unity at tipping. Such studies have been made both on climatic computer models and on real paleoclimate data preceding ancient tipping events. The latter employ reconstituted time-series provided by ice cores, sediments, etc., and seek to establish whether the actual tipping could have been accurately predicted in advance. One such example is the end of the Younger Dryas event, about 11 500 years ago, when the Arctic warmed by 7°C in 50 yrs. A second gives an excellent prediction for the end of "greenhouse" Earth about 34 million years ago when the climate tipped from a tropical state into an icehouse state, using data from tropical Pacific sediment cores. This prediction science is very young, but some encouraging results are already being obtained. Future analyses will clearly need to embrace both real data from improved monitoring instruments, and simulation data generated from increasingly sophisticated predictive models.
COUPLED INDUCTORS-BASED CHAOTIC COLPITTS OSCILLATOR
Authors: BUSCARINO ARTURO , FORTUNA LUIGI , FRASCA MATTIA , SCIUTO GREGORIO
Published: March 2011

In this paper, a new chaotic circuit is introduced, conceived by considering a Colpitts oscillator with the inclusion of two further elements: a coupled inductor and a variable resistor. The proposed circuit exhibits a rich dynamics that has been experimentally characterized through the bifurcation diagram with respect to the resistor value. The main result that can be derived from the analysis of the new circuit leads to a simple way to control chaos in the chaotic Colpitts oscillator by varying a single external control parameter. The same technique has then been applied to the classical periodic Colpitts oscillator, demonstrating how in this way the oscillation frequency can be controlled.
PROPAGATION AND SYNCHRONIZATION OF Ca2+ SPIRAL WAVES IN EXCITABLE MEDIA
Authors: MA JUN , TANG JUN , WANG CHUN-NI , JIA YA
Published: March 2011

Ca2+ spiral wave is observed in a large number of cell types. Based on a Ca2+ model presented by Atri et al., the propagation and synchronization of the intracellular Ca2+ spiral waves are numerically studied and some interesting results are obtained. (i) The largest Lyapunov exponents versus bifurcation parameter is calculated to investigate the oscillation of Ca2+ and it is found that almost all of the largest Lyapunov exponents are negative except for some others that are very close to zero (with an order of magnitude about 10-4 to 10-5). (ii) The two controllable parameters — the concentration of inositol 1,4,5-trisphosphate (IP3) and the diffusion coefficient — play an important role in inducing and supporting the rotating spiral wave, and the critical thresholds for supporting Ca2+ spiral wave are identified by calculating the statistical factor of synchronization in two-dimensional space. (iii) The driving layer (layer-1) can activate the Ca2+ oscillations in the driven layer (layer-2), and Ca2+ spiral wave in the driven layer can also be developed to synchronize the Ca2+ spiral wave in the drive with appropriate coupling intensity no matter whether mono-directional or mutual coupling of Ca2+ is being used. (iv) An optimal synchronization is observed for an intermediate amount of noise in the presence of Gaussian white noise, and for this noise amount, the Ca2+ waves in the two layers reach complete synchronization most quickly, it is a resonance-like behavior due to noise.
Pseudo-Hexagonal Composite Twins in Pulse Electroplated Copper
Authors: Lin Ya-Wen , Kuo Jui-Chao
Published: March 2011

The microstructure and crystallographic texture of copper electrodeposited onto a graphite substrate were examined by scanning electron microscopy, and electron backscatter diffraction. A high twin fraction of 80% was achieved using a pulsed electrodeposition technique under the current density of 0.5 A/cm2. A new twinning cluster, termed in this paper as “pseudohexagonal composite twins,” was observed in pseudohexagonal grains. The pseudohexagonal composite twins possess the crystallographic feature of a rotation angle of 60° around an axis of 〈111〉.
Role of the foregut in the early improvement in glucose tolerance and insulin sensitivity following Roux-en-Y gastric bypass surgery
Authors: Hansen Erik N. , Tamboli Robyn A. , Isbell James M. , Saliba Jabbar , Dunn Julia P. , Marks-Shulman Pamela A. , Abumrad Naji N.
Published: March 2011

Bypass of the foregut following Roux-en-Y gastric bypass (RYGB) surgery results in altered nutrient absorption, which is proposed to underlie the improvement in glucose tolerance and insulin sensitivity. We conducted a prospective crossover study in which a mixed meal was delivered orally before RYGB (gastric) and both orally (jejunal) and by gastrostomy tube (gastric) postoperatively (1 and 6 wk) in nine subjects. Glucose, insulin, and incretin responses were measured, and whole-body insulin sensitivity was estimated with the insulin sensitivity index composite. RYGB resulted in an improved glucose, insulin, and glucagon-like peptide-1 (GLP-1) area under the curve (AUC) in the first 6 wk postoperatively (all P ≤ 0.018); there was no effect of delivery route (all P ≥ 0.632) or route × time interaction (all P ≥ 0.084). The glucose-dependent insulinotropic polypeptide (GIP) AUC was unchanged after RYGB ( P = 0.819); however, GIP levels peaked earlier after RYGB with jejunal delivery. The ratio of insulin AUC to GLP-1 and GIP AUC decreased after surgery ( P =.001 and 0.061, respectively) without an effect of delivery route over time (both P ≥ 0.646). Insulin sensitivity improved post-RYGB ( P = 0.001) with no difference between the gastric and jejunal delivery of the mixed meal over time ( P = 0.819). These data suggest that exclusion of nutrients from the foregut with RYGB does not improve glucose tolerance or insulin sensitivity. However, changes in the foregut response post-RYGB due to lack of nutrient exposure cannot be excluded. Our findings suggest that foregut bypass may alter the incretin response by enhanced nutrient delivery to the hindgut.
Combination treatment of angiotensin II type I receptor blocker and new oral iron chelator attenuates progression of nonalcoholic steatohepatitis in rats
Authors: Kaji Kosuke , Yoshiji Hitoshi , Kitade Mitsuteru , Ikenaka Yasuhide , Noguchi Ryuichi , Shirai Yusaku , Aihara Yosuke , Namisaki Tadashi , Yoshii Junichi , Yanase Koji , Tsujimoto Tatsuhiro , Kawaratani Hideto , Fukui Hiroshi
Published: March 2011

Angiotensin II type I receptor blocker and iron chelator reportedly exert suppressive effects on nonalcoholic steatohepatitis (NASH) progression, including liver fibrosis and hepatocarcinogenesis. The aim of this study was to elucidate the combined effect of losartan (LOS), an angiotensin II type I receptor blocker, and deferasirox (DSX), a newly developed oral iron chelator, on the progression of NASH in rats. To induce NASH, F344 rats were fed a choline-deficient l-amino acid-defined diet for 12 wk, and the effects of LOS and DSX at clinically comparable low doses were elucidated in conjunction with oxidative stress, neovascularization, and hepatic stellate cells (HSC) activation, all known to play important roles in the progression of NASH. Treatment with both LOS and DSX suppressed choline-deficient l-amino acid-defined diet-induced liver fibrosis development and hepatocarcinogenesis. This combination treatment exerted a stronger inhibitory effect compared with treatment with a single agent. These inhibitory effects occurred almost concurrently with the suppression of oxidative stress, neovascularization, and HSC activation. Our in vitro study demonstrated that LOS and DSX inhibited angiotensin II-induced proliferation, transforming growth factor-β1expression of activated HSC, and in vitro angiogenesis. These results indicated that dual inhibition by combined treatment of LOS and DSX attenuated the progression of NASH. Since both agents are widely used in clinical practice, this combination therapy may represent a potential new strategy against NASH in the near future.