Phenotypic integration does not constrain phenotypic plasticity: differential plasticity of traits is associated to their integration across environments.

Understanding constraints to phenotypic plasticity is key given its role on the response of organisms to environmental change. It has been suggested that phenotypic integration, the structure of trait covariation, could limit trait plasticity. However, the relationship between plasticity and integration is far from resolved. Using a database of functional plasticity to drought of a Mediterranean shrub that included 20 ecophysiological traits, we assessed environmentally-induced changes in phenotypic integration and whether integration constrained the expression of plasticity, accounting for the within-environment phenotypic variation of traits. Furthermore, we provide the first test of the association between differential trait plasticity and trait integration across an optimum and a stressful environment. Phenotypic plasticity was positively associated with phenotypic integration in both environments, but this relationship was lost when phenotypic variation was considered. The similarity in the plastic response of two traits predicted their integration across environments, with integrated traits having more similar plasticity. Such variation in the plasticity of traits partly explained the lower phenotypic integration found in the stressful environment. We found no evidence that integration may constitute an internal constraint to plasticity. Rather, we present the first empirical demonstration that differences in plastic responses may involve a major reorganization of the relationships among traits, and challenge the notion that stress generally induces a tighter phenotype.

Selection patterns on early-life phenotypic traits in Pinus sylvestris are associated with precipitation and temperature along a climatic gradient in Europe.

Understanding the dynamics of selection is key to predicting the response of tree species to new environmental conditions in the current context of climate change. However, selection patterns acting on early recruitment stages and their climatic drivers remain largely unknown in most tree species, despite being a critical period of their life cycle. We measured phenotypic selection on Pinus sylvestris seed mass, emergence time and early growth rate over 2 yr in four common garden experiments established along the latitudinal gradient of the species in Europe. Significant phenotypic plasticity and among-population genetic variation were found for all measured phenotypic traits. Heat and drought negatively affected fitness in the southern sites, but heavy rainfalls also decreased early survival in middle latitudes. Climate-driven directional selection was found for higher seed mass and earlier emergence time, while the form of selection on seedling growth rates differed among sites and populations. Evidence of adaptive and maladaptive phenotypic plasticity was found for emergence time and early growth rate, respectively. Seed mass, emergence time and early growth rate have an adaptive role in the early stages of P. sylvestris and climate strongly influences the patterns of selection on these fitness-related traits.

Biotic homogenization can decrease landscape-scale forest multifunctionality.

Many experiments have shown that local biodiversity loss impairs the ability of ecosystems to maintain multiple ecosystem functions at high levels (multifunctionality). In contrast, the role of biodiversity in driving ecosystem multifunctionality at landscape scales remains unresolved. We used a comprehensive pan-European dataset, including 16 ecosystem functions measured in 209 forest plots across six European countries, and performed simulations to investigate how local plot-scale richness of tree species (α-diversity) and their turnover between plots (ß-diversity) are related to landscape-scale multifunctionality. After accounting for variation in environmental conditions, we found that relationships between α-diversity and landscape-scale multifunctionality varied from positive to negative depending on the multifunctionality metric used. In contrast, when significant, relationships between ß-diversity and landscape-scale multifunctionality were always positive, because a high spatial turnover in species composition was closely related to a high spatial turnover in functions that were supported at high levels. Our findings have major implications for forest management and indicate that biotic homogenization can have previously unrecognized and negative consequences for large-scale ecosystem multifunctionality.

Continental mapping of forest ecosystem functions reveals a high but unrealised potential for forest multifunctionality.

Humans require multiple services from ecosystems, but it is largely unknown whether trade-offs between ecosystem functions prevent the realisation of high ecosystem multifunctionality across spatial scales. Here, we combined a comprehensive dataset (28 ecosystem functions measured on 209 forest plots) with a forest inventory dataset (105,316 plots) to extrapolate and map relationships between various ecosystem multifunctionality measures across Europe. These multifunctionality measures reflected different management objectives, related to timber production, climate regulation and biodiversity conservation/recreation. We found that trade-offs among them were rare across Europe, at both local and continental scales. This suggests a high potential for 'win-win' forest management strategies, where overall multifunctionality is maximised. However, across sites, multifunctionality was on average 45.8-49.8% below maximum levels and not necessarily highest in protected areas. Therefore, using one of the most comprehensive assessments so far, our study suggests a high but largely unrealised potential for management to promote multifunctional forests.

Biodiversity and ecosystem functioning relations in European forests depend on environmental context.

The importance of biodiversity in supporting ecosystem functioning is generally well accepted. However, most evidence comes from small-scale studies, and scaling-up patterns of biodiversity-ecosystem functioning (B-EF) remains challenging, in part because the importance of environmental factors in shaping B-EF relations is poorly understood. Using a forest research platform in which 26 ecosystem functions were measured along gradients of tree species richness in six regions across Europe, we investigated the extent and the potential drivers of context dependency of B-EF relations. Despite considerable variation in species richness effects across the continent, we found a tendency for stronger B-EF relations in drier climates as well as in areas with longer growing seasons and more functionally diverse tree species. The importance of water availability in driving context dependency suggests that as water limitation increases under climate change, biodiversity may become even more important to support high levels of functioning in European forests.

CyberKnife Stereotactic Radiosurgery for Uveal Melanoma: First Case Series in Central America.

Introduction: Uveal melanoma is the most common primary intraocular malignancy in adults, affecting primarily the choroid of the eye. Plaque brachytherapy is the most common procedure for the treatment of small choroidal melanoma, especially in posteriorly located tumors. However, modern radiotherapy techniques, such as CyberKnife or Gamma knife stereotactic radiosurgery (SRS) and proton beam radiotherapy, have shown better results in tumor control and eye retention. Recent studies have indicated that SRS is a promising non-invasive, single-session treatment option, with most studies reporting the best outcomes when using ≥21-22 Gy. However, there is no consistent protocol for managing this pathology using CyberKnife, not only in terms of dose but also fractions. Case Presentations: Here, we report the first case series of patients (n = 4, age range 38-64 years, median age 52.5 years) with choroidal UM in Central America who were treated with CyberKnife SRS (22 Gy in one session). During the follow-up (range 25-29 months, median 27.5 months), a 100% control rate with no systemic metastatic disease has been achieved. We found a statistically significant reduction in the largest basal diameter at 24 months for all tumors. However, visual acuity has progressively decreased in most patients. Notably, two of our patients developed radiation maculopathy, and the other two developed radiation retinopathy after SRS. Conclusions: Our findings suggest that future studies should evaluate the use of different prophylactic therapies to prevent the development of side effects. The clinical management of toxicities presented in our report can serve as a reference in the clinical practice of other centers. Our report supports the growing body of evidence showing that CyberKnife radiosurgery is a safe and effective therapeutic option for the treatment of UM.

The GenTree Platform: growth traits and tree-level environmental data in 12 European forest tree species.

BACKGROUND: Progress in the field of evolutionary forest ecology has been hampered by the huge challenge of phenotyping trees across their ranges in their natural environments, and the limitation in high-resolution environmental information. FINDINGS: The GenTree Platform contains phenotypic and environmental data from 4,959 trees from 12 ecologically and economically important European forest tree species: Abies alba Mill. (silver fir), Betula pendula Roth. (silver birch), Fagus sylvatica L. (European beech), Picea abies (L.) H. Karst (Norway spruce), Pinus cembra L. (Swiss stone pine), Pinus halepensis Mill. (Aleppo pine), Pinus nigra Arnold (European black pine), Pinus pinaster Aiton (maritime pine), Pinus sylvestris L. (Scots pine), Populus nigra L. (European black poplar), Taxus baccata L. (English yew), and Quercus petraea (Matt.) Liebl. (sessile oak). Phenotypic (height, diameter at breast height, crown size, bark thickness, biomass, straightness, forking, branch angle, fructification), regeneration, environmental in situ measurements (soil depth, vegetation cover, competition indices), and environmental modeling data extracted by using bilinear interpolation accounting for surrounding conditions of each tree (precipitation, temperature, insolation, drought indices) were obtained from trees in 194 sites covering the species' geographic ranges and reflecting local environmental gradients. CONCLUSION: The GenTree Platform is a new resource for investigating ecological and evolutionary processes in forest trees. The coherent phenotyping and environmental characterization across 12 species in their European ranges allow for a wide range of analyses from forest ecologists, conservationists, and macro-ecologists. Also, the data here presented can be linked to the GenTree Dendroecological collection, the GenTree Leaf Trait collection, and the GenTree Genomic collection presented elsewhere, which together build the largest evolutionary forest ecology data collection available.

Intraspecific perspective of phenotypic coordination of functional traits in Scots pine.

Functional traits have emerged as a key to understand species responses to environmental conditions. The concerted expression of multiple traits gives rise to the phenotype of each individual, which is the one interacting with the environment and evolving. However, patterns of trait covariation and how they vary in response to environmental conditions remain poorly understood, particularly at the intraspecific scale. Here, we have measured traits at different scales and in different organs, and analysed their covariation in a large number of conspecifics distributed in two contrasting environments. We expected significant correlations among traits, not only within clusters of traits as found in global, multispecies studies, but also among clusters, with more relationships within clusters, due to genetic constraints, and among clusters due to more coordinated phenotypes than community level, multispecies studies. We surveyed 100 Pinus sylvestris trees in a Mediterranean mountainous area distributed in two contrasting elevations. We measured 13 functional traits, in three clusters (leaf, stem and whole-plant traits), and analysed their variation and coordination. We found significant coordination among traits belonging to different clusters that reveals coordinated phenotypes. However, we found fewer correlations within trait clusters than initially expected. Trait correlation structures (number, intensity and type of correlations among traits) differed among individuals at different elevations. We observed more correlations within trait clusters at low elevation compared to those at high elevation. Moreover, the higher number of correlations among different trait clusters and the lower trait variation at the higher elevation suggests that variability decreases under more stressful conditions. Altogether, our results reveal that traits at intraspecific scale are coordinated in a broad network and not only within clusters of traits but also that this trait covariation is significantly affected by environmental conditions.

Importance of overstorey attributes for understorey litter production and nutrient cycling in European forests.

BACKGROUND: In contrast with the negligible contribution of the forest understorey to the total aboveground phytobiomass of a forest, its share in annual litter production and nutrient cycling may be more important. Whether and how this functional role of the understorey differs across forest types and depends upon overstorey characteristics remains to be investigated. METHODS: We sampled 209 plots of the FunDivEUROPE Exploratory Platform, a network of study plots covering local gradients of tree diversity spread over six contrasting forest types in Europe. To estimate the relative contribution of the understorey to carbon and nutrient cycling, we sampled non-lignified aboveground understorey biomass and overstorey leaf litterfall in all plots. Understorey samples were analysed for C, N and P concentrations, overstorey leaf litterfall for C and N concentrations. We additionally quantified a set of overstorey attributes, including species richness, proportion of evergreen species, light availability (representing crown density) and litter quality, and investigated whether they drive the understorey's contribution to carbon and nutrient cycling. RESULTS AND CONCLUSIONS: Overstorey litter production and nutrient stocks in litterfall clearly exceeded the contribution of the understorey for all forest types, and the share of the understorey was higher in forests at the extremes of the climatic gradient. In most of the investigated forest types, it was mainly light availability that determined the contribution of the understorey to yearly carbon and nutrient cycling. Overstorey species richness did not affect the contribution of the understorey to carbon and nutrient cycling in any of the investigated forest types.

Author Correction: The GenTree Dendroecological Collection, tree-ring and wood density data from seven tree species across Europe.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

The GenTree Dendroecological Collection, tree-ring and wood density data from seven tree species across Europe.

The dataset presented here was collected by the GenTree project (EU-Horizon 2020), which aims to improve the use of forest genetic resources across Europe by better understanding how trees adapt to their local environment. This dataset of individual tree-core characteristics including ring-width series and whole-core wood density was collected for seven ecologically and economically important European tree species: silver birch (Betula pendula), European beech (Fagus sylvatica), Norway spruce (Picea abies), European black poplar (Populus nigra), maritime pine (Pinus pinaster), Scots pine (Pinus sylvestris), and sessile oak (Quercus petraea). Tree-ring width measurements were obtained from 3600 trees in 142 populations and whole-core wood density was measured for 3098 trees in 125 populations. This dataset covers most of the geographical and climatic range occupied by the selected species. The potential use of it will be highly valuable for assessing ecological and evolutionary responses to environmental conditions as well as for model development and parameterization, to predict adaptability under climate change scenarios.

Primary acquired melanosis of the conjunctiva: risks for progression to melanoma in 311 eyes. The 2006 Lorenz E. Zimmerman lecture.

PURPOSE: To evaluate the clinical features and risks for transformation of conjunctival primary acquired melanosis (PAM) into melanoma. DESIGN: Noncomparative case series. PARTICIPANTS: Three hundred eleven eyes with conjunctival PAM without melanoma at initial examination from a single-center tertiary referral center. METHODS: Retrospective chart review with evaluation of the clinical features of PAM at initial presentation and follow-up. Times to PAM enlargement, recurrence, and transformation into melanoma were assessed using Kaplan-Meier estimates. Risk factors for these outcomes were analyzed using Cox proportional hazards regressions. MAIN OUTCOME MEASURES: Primary acquired melanosis enlargement, recurrence, and transformation into melanoma. RESULTS: Mean patient age at diagnosis of PAM was 56 years (range, 15-90), 62% were female, and 96% were Caucasian. The conjunctival quadrant(s) affected by PAM were temporal (57%), inferior (45%), nasal (42%), and superior (37%). The anatomic location(s) of PAM included bulbar conjunctiva (91%), limbal conjunctiva (55%), cornea (23%), forniceal conjunctiva (13%), palpebral conjunctiva (12%), and caruncle (11%). Primary acquired melanosis extended for a mean of 3 clock hours (range, 1-12). Initial management included observation (n = 194 eyes [62%]), biopsy combined with cryotherapy (n = 107 eyes [34%]), and topical chemotherapy and/or cryotherapy without biopsy (n = 10 [4%]). Of PAM that was observed, Kaplan-Meier estimates at 10 years revealed PAM enlargement in 35% and transformation into melanoma in 12%. Of those that underwent incisional or excisional biopsy, 10-year estimates of PAM recurrence and transformation into melanoma were 58% and 11%, respectively. Progression to melanoma occurred in 0% of cases of PAM without atypia, 0% of cases of PAM with mild atypia, and 13% of cases of PAM with severe atypia. Of the 9 patients with PAM who developed melanoma, none have developed systemic metastasis. Multivariable analysis revealed that the most significant factor for both PAM recurrence and progression to melanoma was extent of PAM in clock hours. CONCLUSION: Primary acquired melanosis without atypia or with mild atypia shows 0% progression to melanoma, whereas PAM with severe atypia shows progression to melanoma in 13%. The greater the extent of PAM in clock hours, the greater the risk for transformation to melanoma.

Tree diversity affects chlorophyll a fluorescence and other leaf traits of tree species in a boreal forest.

An assemblage of tree species with different crown properties creates heterogeneous environments at the canopy level. Changes of functional leaf traits are expected, especially those related to light interception and photosynthesis. Chlorophyll a fluorescence (ChlF) properties in dark-adapted leaves, specific leaf area, leaf nitrogen content (N) and carbon isotope composition (δ13C) were measured on Picea abies (L.) H.Karst., Pinus sylvestris L. and Betula pendula Roth. in monospecific and mixed boreal forests in Europe, in order to test whether they were affected by stand species richness and composition. Photosynthetic efficiency, assessed by induced emission of leaf ChlF, was positively influenced in B. pendula by species richness, whereas P. abies showed higher photosynthetic efficiency in monospecific stands. Pinus sylvestris had different responses when it coexisted with P. abies or B. pendula. The presence of B. pendula, but not of P. abies, in the forest had a positive effect on the efficiency of photosynthetic electron transport and N in P. sylvestris needles, and the photosynthetic responses were positively correlated with an increase of leaf δ13C. These effects on P. sylvestris may be related to high light availability at the canopy level due to the less dense canopy of B. pendula. The different light requirements of coexisting species was the most important factor affecting the distribution of foliage in the canopy, driving the physiological responses of the mixed species. Future research directions claim to enhance the informative potential of the methods to analyse the responses of pure and mixed forests to environmental factors, including a broader set of plant species' functional traits and physiological responses.

Intraspecific leaf trait variability along a boreal-to-tropical community diversity gradient.

Disentangling the mechanisms that shape community assembly across diversity gradients is a central matter in ecology. While many studies have explored community assembly through species average trait values, there is a growing understanding that intraspecific trait variation (ITV) can also play a critical role in species coexistence. Classic biodiversity theory hypothesizes that higher diversity at species-rich sites can arise from narrower niches relative to species-poor sites, which would be reflected in reduced ITV as species richness increases. To explore how ITV in woody plant communities changes with species richness, we compiled leaf trait data (leaf size and specific leaf area) in a total of 521 woody plant species from 21 forest communities that differed dramatically in species richness, ranging from boreal to tropical rainforests. At each forest, we assessed ITV as an estimate of species niche breadth and we quantified the degree of trait overlap among co-occurring species as a measure of species functional similarity. We found ITV was relatively invariant across the species richness gradient. In addition, we found that species functional similarity increased with diversity. Contrary to the expectation from classic biodiversity theory, our results rather suggest that neutral processes or equalizing mechanisms can be acting as potential drivers shaping community assembly in hyperdiverse forests.

Jack-of-all-trades effects drive biodiversity-ecosystem multifunctionality relationships in European forests.

There is considerable evidence that biodiversity promotes multiple ecosystem functions (multifunctionality), thus ensuring the delivery of ecosystem services important for human well-being. However, the mechanisms underlying this relationship are poorly understood, especially in natural ecosystems. We develop a novel approach to partition biodiversity effects on multifunctionality into three mechanisms and apply this to European forest data. We show that throughout Europe, tree diversity is positively related with multifunctionality when moderate levels of functioning are required, but negatively when very high function levels are desired. For two well-known mechanisms, 'complementarity' and 'selection', we detect only minor effects on multifunctionality. Instead a third, so far overlooked mechanism, the 'jack-of-all-trades' effect, caused by the averaging of individual species effects on function, drives observed patterns. Simulations demonstrate that jack-of-all-trades effects occur whenever species effects on different functions are not perfectly correlated, meaning they may contribute to diversity-multifunctionality relationships in many of the world's ecosystems.

Direct and indirect effects of climate on demography and early growth of Pinus sylvestris at the rear edge: changing roles of biotic and abiotic factors.

Global change triggers shifts in forest composition, with warming and aridification being particularly threatening for the populations located at the rear edge of the species distributions. This is the case of Scots pine (Pinus sylvestris) in the Mediterranean Basin where uncertainties in relation to its dynamics under these changing scenarios are still high. We analysed the relative effect of climate on the recruitment patterns of Scots pine and its interactions with local biotic and abiotic variables at different spatial scales. Number of seedlings and saplings was surveyed, and their annual shoot growth measured in 96 plots located across altitudinal gradients in three different regions in the Iberian Peninsula. We found a significant influence of climate on demography and performance of recruits, with a non-linear effect of temperature on the presence of juveniles, and a positive effect of precipitation on their survival. Abundance of juveniles of P. sylvestris that underwent their first summer drought was skewed towards higher altitudes than the altitudinal mean range of the conspecific adults and the optimum elevation for seedlings' emergence. At local level, light availability did not influence juveniles' density, but it enhanced their growth. Biotic interactions were found between juveniles and the herb cover (competition) and between the number of newly emerged seedlings and shrubs (facilitation). Results also highlighted the indirect effect that climate exerts over the local factors, modulating the interactions with the pre-existing vegetation that were more evident at more stressful sites. This multiscale approach improves our understanding of the dynamics of these marginal populations and some management criteria can be inferred to boost their conservation under the current global warming.

Disparity in elevational shifts of European trees in response to recent climate warming.

Predicting climate-driven changes in plant distribution is crucial for biodiversity conservation and management under recent climate change. Climate warming is expected to induce movement of species upslope and towards higher latitudes. However, the mechanisms and physiological processes behind the altitudinal and latitudinal distribution range of a tree species are complex and depend on each tree species features and vary over ontogenetic stages. We investigated the altitudinal distribution differences between juvenile and adult individuals of seven major European tree species along elevational transects covering a wide latitudinal range from southern Spain (37°N) to northern Sweden (67°N). By comparing juvenile and adult distributions (shifts on the optimum position and the range limits) we assessed the response of species to present climate conditions in relation to previous conditions that prevailed when adults were established. Mean temperature increased by 0.86 °C on average at our sites during the last decade compared with previous 30-year period. Only one of the species studied, Abies alba, matched the expected predictions under the observed warming, with a maximum abundance of juveniles at higher altitudes than adults. Three species, Fagus sylvatica, Picea abies and Pinus sylvestris, showed an opposite pattern while for other three species, such as Quercus ilex, Acer pseudoplatanus and Q. petraea, we were no able to detect changes in distribution. These findings are in contrast with theoretical predictions and show that tree responses to climate change are complex and are obscured not only by other environmental factors but also by internal processes related to ontogeny and demography.

Use of Sexual Material Online and At-Risk Sexual Behavior Regarding HIV/AIDS among College Students.

Use of sexual material online (USMO) by young people has been connected with at-risk sexual behavior for HIV/AIDS. Media Richness and Social Cognitive theories propose that rich media offer more information with interactive and audible visual content, which could have a significant impact on people's thinking and behavior. The objective was to determine whether USMO presented by rich media has an influence on at-risk sexual behavior for HIV/AIDS. Two hundred young people participated in the study, and it was found that USMO from rich media is connected to at risk sexual behavior for HIV/AIDS (p<.01). Young people who use rich media for masturbation (F[2,189]=10.169, p<.001), arousal (F[2,189]=4.686, p<.05), stimulation (F[2,189]=8.382, p<.001), and seeking adventures (F[2,189]=6.406, p<.01) were more likely to show at risk sexual behavior for HIV/AIDS. The study also found that young people may experience pleasure from USMO in rich media and feel motivated to model what they observe.

Optical coherence tomography of optic disk melanocytoma in 15 cases.

OBJECTIVE: To describe the optical coherence tomography (OCT) features of optic disk melanocytoma. DESIGN AND PARTICIPANTS: Case series including 15 patients. MAIN OUTCOME MEASURES: OCT characteristics of the tumor. RESULTS: The mean age of the patients was 42 years. By ophthalmoscopy, the mean basal diameter of the tumor was 2.7 mm, and by ultrasonography, the mean thickness was 1.8 mm. By OCT, the tumor showed a nodular appearance in 14 cases (93%). The tumor displayed a gradual sloping transition from normal retina into the mass, hyperreflectivity at its anterior tumor surface, and dense posterior shadowing with an optically empty appearance in all 15 cases (100%). Thicker tumors displayed thinner anterior hyperreflective borders and denser shadowing. There were no internal qualities of the tumor or disk visible by OCT due to dense shadowing. Other findings of OCT included vitreous seeds in 2 cases (13%) and adjacent retinal edema in 1 case (7%). There were no cases of retinal traction, subretinal fluid, macular edema, or epiretinal membrane in the macula. CONCLUSIONS: Optic disk melanocytoma shows characteristic features by OCT including a gradual transition from normal retina into nodular tumor, and the mass displays a bright anterior border layer with optically empty internal details.

Análisis de concepto: "decisión de cambio" para mejorar las conductas de salud en el contexto de las enfermedades crónicas en adultos / Analyzing "Decision to Change" in Order to Improve Health Care Behavior in Adult Chronic Disease: "decisão de mudança"para melhorar as condutas de saúde no contexto das doenças crônicas em adultos / Análise de conceito

Objetivo: a fin de contribuir con la clarificación y el desarrollo de conceptos útiles para la ciencia de enfermería en su práctica, este trabajo utilizó la metodología de Rodgers con el fin de proporcionar una definición del concepto "decisión de cambio" (DC) para el mejoramiento de conductas de salud en el contexto de las enfermedades crónicas (obesidad, hipertensión arterial y diabetes). Método: se realizó el análisis de evidencia empírica en bases de datos para identificar atributos, términos subrogados, antecedentes y consecuencias en relación con el concepto DC. De forma complementaria se aplicaron entrevistas semiestructuradas con codificación abierta. Resultados: la decisión de cambio es definida, entonces, como el proceso de elección que requiere de intención y actitud para comprometerse con responsabilidad en el mejoramiento de la conducta de salud, de manera efectiva y permanente respecto de las condiciones sociales y emocionales a las que una persona es sometida ante la presencia de una enfermedad crónica y que requiere de manera impostergable el apoyo familiar y profesional de salud. Conclusión: la decisión de cambio es un juicio de elección que requiere de voluntad permanente para cambiar las conductas de salud y resolver las posibles contingencias que pueda provocar una enfermedad crónica.

Objective: in order to clarify and develop useful concepts for nursing practice, this study used Rodger's methodology with the purpose of defining "Decision to Change" (DC) and thus improve health care behavior when dealing with chronic disease (obesity, hypertension, diabetes). Method: empirical evidence found in databases was analyzed in order to determine the attributes, subrogated terms, background and consequences in the DC concept. To complement this, semi-structured open coded interviews were also applied. Results: thus, the "Decision to Change" can de defined as electing an intention and an attitude to responsibly commit towards effectively and permanently improving behavior towards the social and emotional conditions surrounding a persona affected by chronic disease, who requires immediate support from family and health care providers. Conclusion: decision to change is a deliberate election that requires permanent determination to change health care behavior and solve eventual contingencies resulting from chronic illness.

Objetivo: a fim de contribuir com a classificação e o desenvolvimento de conceitos úteis para a ciência de enfermagem no contexto de sua prática, este trabalho utilizou a metodologia de Rodgers com o propósito de proporcionar uma definição do conceito "decisão de mudanças" (DM) para o melhoramento de condutas de saúde no contexto das doenças crônicas (obesidade, hipertensão arterial e diabetes). Métodos: realizou-se a análise de evidência empírica com bases de dados para identificar atributos, termos substitutos, antecedentes e consequências com relação ao conceito DM. De forma complementar, aplicaram-se entrevistas semiestruturadas com codificação aberta. Resultados: a DM é definida, então, como o processo de eleição que requer intenção e atitude para comprometer-se com responsabilidade no melhoramento da conduta de saúde, de maneira efetiva e permanente, com respeito às condições sociais e emocionais às quais uma pessoa é submetida na presença de doenças crônicas e que requer de maneira urgente o apoio familiar e profissional de saúde. Conclusão: a DM é um julgamento de escolha que requer vontade permanente para mudar as condutas de saúde e resolver as possíveis contingências que possa provocar uma doença crônica.