Globally, functional traits are weak predictors of juvenile tree growth, and we do not know why

1. Plant functional traits, in particular specific leaf area (SLA), wood density and seed mass, are often good predictors of individual tree growth rates within communities. Individuals and species with high SLA, low wood density and small seeds tend to have faster growth rates. 2. If community-level relationships between traits and growth have general predictive value, then similar relationships should also be observed in analyses that integrate across taxa, biogeographic regions and environments. Such global consistency would imply that traits could serve as valuable proxies for the complex suite of factors that determine growth rate, and, therefore, could underpin a new generation of robust dynamic vegetation models. Alternatively, growth rates may depend more strongly on the local environment or growth–trait relationships may vary along environmental gradients. 3. We tested these alternative hypotheses using data on 27 352 juvenile trees, representing 278 species from 27 sites on all forested continents, and extensive functional trait data, 38% of which were obtained at the same sites at which growth was assessed. Data on potential evapotranspiration (PET), which summarizes the joint ecological effects of temperature and precipitation, were obtained from a global data base. 4. We estimated size-standardized relative height growth rates (SGR) for all species, then related them to functional traits and PET using mixed-effect models for the fastest growing species and for all species together. 5. Both the mean and 95th percentile SGR were more strongly associated with functional traits than with PET. PET was unrelated to SGR at the global scale. SGR increased with increasing SLA and decreased with increasing wood density and seed mass, but these traits explained only 3.1% of the variation in SGR. SGR–trait relationships were consistently weak across families and biogeographic zones, and over a range of tree statures. Thus, the most widely studied functional traits in plant ecology were poor predictors of tree growth over large scales. 6. Synthesis. We conclude that these functional traits alone may be unsuitable for predicting growth of trees over broad scales. Determining the functional traits that predict vital rates under specific environmental conditions may generate more insight than a monolithic global relationship can offer

Anxiety, depression, somatization and alcohol abuse. Prevalence rates in a general Belgian community sample.

The results of a psycho-epidemiologic field study are presented. Lifetime and point prevalence rates of eight DSM-III (Diagnostic and Statistical Manual of Mental Disorders) diagnostic categories (generalized anxiety, phobia, panic, obsession-compulsion, major depression/dysthymia, mania, the somatization syndrome and alcohol abuse and dependence) are estimated on the basis of the DISSI (Diagnostic Interview Schedule, Screening Interview). The subjects, 25 to 45 year old adults (N = 240) were randomly selected from local registers. The point prevalence rates are 16.6% for anxiety disorders, followed by affective disorders (12.8%) and by the somatization syndrome (8.9%) and alcohol abuse and dependence (8.5%). Psychosocial correlates of the diagnostic categories are examined and the findings are compared to other field studies using comparable diagnostic tools

L'utilisation du téléphone dans une enquête de santé mentale : analyse de l'impact du rang d'appel, des données manquantes et de l'effet « enquêteur »

Bari ffoi Éric. Vfrc.fr Pierre Rotiiy Michel - Using the telephone for mental health surveys: an analysis of the impact of call rank, non-response and interviewer effect Use of telephone sample surveys on mental health has increased in France in recent years As part of an epidennological survey of the long term psychological consequences of a natural disaster — the 1992 floods in the Vaucluse — this article begins by examining the relationships between call rank and the population's socio demographic characteristics and mental health status, the relationship between missing data, socio demographic characteristics and personality disorders is then examined, finally an attempt is made to evaluate the interviewer effect on the mental health data collected by telephone The results are consistent with those in the literature for the relationship between call rank and socio demographic variables By contrast, no clear relationship is identified between call rank and the various aspects of mental health considered Lastly, non-response on questions of mental health depends on both the socio demographic characteristics and the neurotic tendencies of the respondent The non-response rate and the anxiety level reported by respondents increase when the interviewer is female The implications of these results for telephone collection of data on mental health are discussedBari ffoi Éric, Vfrofr Pierre, Rotu y Michel - L'utilisation du téléphone dans une enquête de santé mentale : analyse de l'impact du rang d'appel, des données manquante:» et de l'effet « enquêteur » Les enquêtes de santé mentale par sondage téléphonique se multiplient en France depuis quelques années Dans le cadre d'une enquête épidemiologique sur les consequences psychologiques à long terme d'une catastrophe naturelle, les inondations de 1992 dans le Vaucluse. on étudie tout d abord les liens entre le rang d'appel, les caractéristiques socio- demographiques de la population et son état de santé mentale L'analyse porte ensuite sur les liens entre les données manquantes, les caractéristiques sociodémographiques et les troubles psychopathologiques, enfin, on évalue l'effet « enquêteur » sur les données de santé mentale recueillies par telephone Les résultats confirment ceux de la littérature quant au lien entre le rang d'appel et les variables sociodémographiques En revanche, la relation entre le rang d'appel et les différentes dimensions de santé mentale étudiées est peu marquee bnfin, l'existence de données manquantes sur les questions de santé mentale depend à la fois des caractéristiques sociodémographiques et des tendances névrotiques du repondant, le taux de données manquantes et le niveau d'anxiété déclarée par les repondants augmentent si l'enquêteur est de sexe féminin Les implications de ces résultats pour le recueil des données de santé mentale par telephone sont discutéesBari ffoi Fric Vfrgfr Pierre. Rotiiy Michel - El uso del teléfono en una encuesta sobre salud mental: análisis del impacto del rango de llamada, de los datos no disponibles y del efecto "encuestador" I as encuestas de salud mental por sondeo telefónico se han multiplicado en Francia en los últimos anos Fn el marco de una encuesta epidemiologica sobre las consecuencias psico- logicas a largo pla/o de una catastrofe natural, las ínundaciones de 1992 en Vaucluse, anali- /amos en primer lugar la relación entre el rango de llamada, las caractensticas souo- demograficas de la poblacion y su estado de salud mental fcn segundo lugar, examinamos la relación entre los datos no disponibles, las caractensticas socio demográficas y los problemas psico-patologicos Para ternnnar, evaluamos el efecto "encuestador' sobre los datos de salud mental recogidos por telefono Los resultados, como la literatura existente, sugieren que exis te una relación entre el rango de llamada y las variables souo-demograficas bn cambio, no se demuestra una tuerte relación entre el rango de llamada y las distintas dimensiones de salud mental La falta de datos sobre salud mental dépende a la ve/ de las caractensticas socio-de- mograficas y de las tendenuas neuróticas del encuestado, la proporción de datos no disponibles y el nivel de ansiedad declarado son mas elevados entre los encuestados de sexo femenino Ы articule discute las implicaciones de estos resultados para la recogida de datos sobre salud mental por telcfonoBaruffol Éric, Verger P., Rotily M. L'utilisation du téléphone dans une enquête de santé mentale : analyse de l'impact du rang d'appel, des données manquantes et de l'effet « enquêteur ». In: Population, 56ᵉ année, n°6, 2001. pp. 987-1010

L'utilisation du telephone dans une enquete de sante mentale: analyse de l'impact du rang d'appel, des donnees manquantes et de l'effet "enqueteur"

Use of telephone sample surveys on mental health has increased in France in recent years. As part of an epidemiological survey of the long-term psychological consequences of a natural disaster-the 1992 floods in the Vaucluse-this article begins by examining the relationships between call rank and the population's socio-demographic characteristics and mental health status; the relationship between missing data, socio-demographic characteristies and personality disorders is then examined; finally an attempt is made to evaluate the interviewer effect on the mental health data collected by telephone. The results are consistent with those in the literature for the relationship between call rank and socio-demographic variables. By contrast, no clear relationship is identified between call rank and the various aspects of mental health considered. Lastly, non-response on questions of mental health depends on both the socio-demographic characteristics and the neurotic tendencies of the respondent. The non-response rate and the anxiety level reported by respondents increase when the interviewer is female. The implications of these results for telephone collection of data on mental health are discussed

Impact of tree saplings on the kinetic energy of rainfall—The importance of stand density, species identity and tree architecture in subtropical forests in China

In order to estimate the influence of plant architectural traits on the erosivity of throughfall we studied throughfall kinetic energy (KE) under tree saplings in a plantation-like experiment in the humid subtropics. Our analyses of rainfall and throughfall KE are based on measurements using calibrated splash cups. Two experiments were carried out, one focusing on density effects and the other testing for species-specific effects and effects of species mixtures. The major architectural traits were measured to characterize sapling morphology. Mixed effects models were used for statistical analysis. In both models, rainfall KE was identified as the most important effect on throughfall KE. Overall, rainfall KE per area was reduced by 59% below the canopy of the studied saplings. We found a significant effect of sapling density on throughfall KE. This is primarily due to the relation between free throughfall and released throughfall. As free throughfall possesses a far higher KE than released throughfall originating from saplings, lower sapling density results in higher total throughfall KE. We also showed that the influence of density on throughfall KE decreases with increasing sapling height due to lateral canopy growth of the saplings. Throughfall KE was significantly different among species. We attribute this to species-specific differences in crown architectural traits. These traits have opposite influence on throughfall KE and interact with each other. Depending on its magnitude, one crown trait can possibly superimpose contrary effects of others

L-lysine dose dependently delays gastric emptying and increases intestinal fluid volume in humans and rats

BACKGROUND: Novel sensory inputs for the control of food intake and gastrointestinal (GI) function are of increasing interest due to the rapid increase in nutrition-related diseases. The essential amino acid L-lysine was demonstrated to have a selective impact on food intake, gastric emptying, and intestinal transit in rats, thus indicating a potential novel direct sensory input to assess dietary protein content and quality. The aim of this study was to assess translational aspects of this finding and to investigate the dose-dependent effect of L-lysine on human and rat GI function. METHODS: L-lysine doses from 0-800 mg in rats and 0.5-7.5 g in humans were analyzed for their effect on gastric emptying and GI secretion. Human GI function was assessed non-invasively using magnetic resonance imaging (MRI), rat data were acquired using standard lethal measurement methods. L-lysine dose dependently delayed gastric emptying and stimulated GI secretion in rats as reflected by residual phenol red content and increased gastric wet weight. KEY RESULTS: The dose-dependent delay in gastric emptying observed in rats was confirmed in humans with an increase in halftime of gastric emptying of 4 min/g L-lysine, p < 0.01. Moreover, a dose-dependent increase in intestinal fluid accumulation was observed (0.4 mL/min/g L-lysine, p < 0.0001). No effect on alkaline tide, glucose concentration, hematocrit, or visceral sensations was detected. CONCLUSIONS & INFERENCES: This translational study demonstrates comparable dose-dependent effects of intragastric L-lysine on GI function in humans and rats and suggests a broader role for individual amino acids in the control of GI motility and secretion in vivo

Globally, functional traits are weak predictors of juvenile tree growth, and we do not know why

Plant functional traits, in particular specific leaf area (SLA), wood density and seed mass, are often good predictors of individual tree growth rates within communities. Individuals and species with high SLA, low wood density and small seeds tend to have faster growth rates. If community-level relationships between traits and growth have general predictive value, then similar relationships should also be observed in analyses that integrate across taxa, biogeographic regions and environments. Such global consistency would imply that traits could serve as valuable proxies for the complex suite of factors that determine growth rate, and, therefore, could underpin a new generation of robust dynamic vegetation models. Alternatively, growth rates may depend more strongly on the local environment or growth-trait relationships may vary along environmental gradients. We tested these alternative hypotheses using data on 27 352 juvenile trees, representing 278 species from 27 sites on all forested continents, and extensive functional trait data, 38% of which were obtained at the same sites at which growth was assessed. Data on potential evapotranspiration (PET), which summarizes the joint ecological effects of temperature and precipitation, were obtained from a global data base. We estimated size-standardized relative height growth rates (SGR) for all species, then related them to functional traits and PET using mixed-effect models for the fastest growing species and for all species together. Both the mean and 95th percentile SGR were more strongly associated with functional traits than with PET. PET was unrelated to SGR at the global scale. SGR increased with increasing SLA and decreased with increasing wood density and seed mass, but these traits explained only 3.1% of the variation in SGR. SGR-trait relationships were consistently weak across families and biogeographic zones, and over a range of tree statures. Thus, the most widely studied functional traits in plant ecology were poor predictors of tree growth over large scales. Synthesis. We conclude that these functional traits alone may be unsuitable for predicting growth of trees over broad scales. Determining the functional traits that predict vital rates under specific environmental conditions may generate more insight than a monolithic global relationship can offer. The most widely studied functional traits in plant ecology, specific leaf area, wood density and seed mass, were only weakly associated with tree growth rates over broad scales. Assessing trait-growth relationships under specific environmental conditions may generate more insight than a global relationship can offer