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New (a)biotic conditions resulting from climate change are expected to change disturbance dynamics, such as windthrow, forest fires, droughts, and insect outbreaks, and their interactions. These unprecedented natural disturbance dynamics might alter the capability of forest ecosystems to buffer atmospheric CO2 increases, potentially leading forests to transform from sinks into sources of CO2. This study aims to enhance the ORCHIDEE land surface model to study the impacts of climate change on the dynamics of the bark beetle, Ips typographus, and subsequent effects on forest functioning. The Ips typographus outbreak model is inspired by previous work from Temperli et al. (2013) for the LandClim landscape model. The new implementation of this model in ORCHIDEE r8627 accounts for key differences between ORCHIDEE and LandClim: (1) the coarser spatial resolution of ORCHIDEE; (2) the higher temporal resolution of ORCHIDEE; and (3) the pre-existing process representation of windthrow, drought, and forest structure in ORCHIDEE. Simulation experiments demonstrated the capability of ORCHIDEE to simulate a variety of post-disturbance forest dynamics observed in empirical studies. Through an array of simulation experiments across various climatic conditions and windthrow intensities, the model was tested for its sensitivity to climate, initial disturbance, and selected parameter values. The results of these tests indicated that with a single set of parameters, ORCHIDEE outputs spanned the range of observed dynamics. Additional tests highlighted the substantial impact of incorporating Ips typographus outbreaks on carbon dynamics. Notably, the study revealed that modeling abrupt mortality events as opposed to a continuous mortality framework provides new insights into the short-term carbon sequestration potential of forests under disturbance regimes by showing that the continuous mortality framework tends to overestimate the carbon sink capacity of forests in the 20- to 50-year range in ecosystems under high disturbance pressure compared to scenarios with abrupt mortality events. This model enhancement underscores the critical need to include disturbance dynamics in land surface models to refine predictions of forest carbon dynamics in a changing climate.

Large amounts of carbon flow through tropical ecosystems every year, from which a part is sequestered in biomass through tree growth. However, the effects of ongoing warming and drying on tree growth and carbon sequestration in tropical forest is still highly uncertain. Field observations are sparse and limited to a few sites, while remote sensing analysis shows diverging growth responses to past droughts that cannot be interpreted with confidence. To reconcile data from field observations and remote sensing, we collated in situ measurements of stem growth and leaf litterfall from inventory plots across the Amazon region and other neotropical ecosystems. These data were used to train two machine-learning models and to evaluate model performance on reproducing stem growth and litterfall rates. The models utilized multiple climatological variables and other geospatial datasets (terrain, soil and vegetation properties) as explanatory variables. The output consisted of monthly estimates of leaf litterfall (R2= 0.71, NRMSE = 9.4 %) and stem growth (R2= 0.54, NRMSE = 10.6 %) across the neotropics from 1982 to 2019 at a high spatial resolution (0.1∘). Modelled time series allow us to assess the impacts of the 2005 and 2015 droughts in the Amazon basin on regional scales. The more severe 2015 drought was estimated to have caused widespread declines in stem growth (−1.8σ), coinciding with enhanced leaf fall (+1.4σ), which were only locally apparent in 2005. Regions in the Amazon basin that flushed leaves at the onset of both droughts (+0.9σ∼+2.0σ) showed positive anomalies in remotely sensed enhanced vegetation index, while sun-induced fluorescence and vegetation optical depth were reduced. The previously observed counterintuitive response of canopy green-up during drought in the Amazon basin detected by many remote sensing analyses can therefore be a result of enhanced leaf flushing at the onset of a drought. The long-term estimates of leaf litterfall and stem growth point to a decline in stem growth and a simultaneous increase in leaf litterfall in the Amazon basin since 1982. These trends are associated with increased warming and drying of the Amazonian climate and could point to a further decline in the Amazon carbon sink strength.

The effects of future warming and drying on tropical forest functioning remain largely unresolved. Here, we conduct a meta-analysis of observed drought responses in Neotropical humid forests, focusing on carbon and water exchange. Measures of leaf-, tree- and ecosystem-scale performance were retrieved from 145 published studies conducted across 232 sites in Neotropical forests. Differentiating between seasonal and episodic drought, we find that (1) during seasonal drought the increase in atmospheric evaporative demand and a decrease in soil matric potential result in a decline in leaf water potential, stomatal conductance, leaf photosynthesis and stem diameter growth while leaf litterfall and leaf flushing increase. (2) During episodic drought, we observe a further decline in stomatal conductance, photosynthesis, stem growth and, in contrast to seasonal drought, a decline also in daily tree transpiration. Responses of ecosystem-scale processes, productivity and evapotranspiration are of a smaller magnitude and often not significant. Furthermore, we find that the magnitude and direction of a drought-induced change in photosynthesis, stomatal conductance and transpiration reported in a study is correlated to study-averaged wood density. Although wood density is often not functionally related to plant hydraulic properties, we find that it is a good proxy for hydraulic behaviour and can be used to predict leaf- and tree-scale responses to drought. We present new insights into the functioning of tropical forest in response to drought and present novel relationships between wood density and tropical-tree responses to drought.

Natural and anthropogenic disturbances, in particular forest management, affect forest age structures all around the globe. Forest age structures in turn influence key land surface processes, such as photosynthesis and thus the carbon cycle. Yet, many dynamic global vegetation models (DGVMs), including those used as land surface models (LSMs) in Earth system models (ESMs), do not account for subgrid forest age structures, despite being used to investigate land-use effects on the global carbon budget or simulating biogeochemical responses to climate change. In this paper we present a new scheme to introduce forest age classes in hierarchical tile-based DGVMs combining benefits of recently applied approaches the first being a computationally efficient age-dependent simulation of all relevant processes, such as photosynthesis and respiration, using a restricted number of age classes and the second being the tracking of the exact forest age, which is a prerequisite for any implementation of age-based forest management. This combination is achieved by using the tile hierarchy to track the area fraction for each age on an aggregated plant functional type level, whilst simulating the relevant processes for a set of age classes. We describe how we implemented this scheme in JSBACH4, the LSM of the ICOsahedral Non-hydrostatic Earth system model (ICON-ESM). Subsequently, we compare simulation output to global observation-based products for gross primary production, leaf area index, and above-ground biomass to assess the ability of simulations with and without age classes to reproduce the annual cycle and large-scale spatial patterns of these variables. The comparisons show decreasing differences and increasing computation costs with an increasing number of distinguished age classes. The results demonstrate the benefit of the introduction of age classes, with the optimal number of age classes being a compromise between computation costs and error reduction.

Earth system models (ESMs) are currently the most advanced tools with which to study the interactions among humans, ecosystem productivity, and the climate. The inclusion of storm damage in ESMs has long been hampered by their big-leaf approach, which ignores the canopy structure information that is required for process-based wind-throw modelling. Recently the big-leaf assumptions in the large-scale land surface model ORCHIDEE-CAN were replaced by a three-dimensional description of the canopy structure. This opened the way to the integration of the processes from the small-scale wind damage risk model ForestGALES into ORCHIDEE-CAN. The integration of ForestGALES into ORCHIDEE-CAN required, however, developing numerically efficient solutions to deal with (1) landscape heterogeneity, i.e. account for newly established forest edges for the parameterization of gusts; (2) downscaling spatially and temporally aggregated wind fields to obtain more realistic wind speeds that would represents gusts; and (3) downscaling storm damage within the 2500 km2 pixels of ORCHIDEE-CAN. This new version of ORCHIDEE-CAN was parameterized over Sweden. Subsequently, the performance of the model was tested against data for historical storms in southern Sweden between 1951 and 2010 and south-western France in 2009. In years without big storms, here defined as a storm damaging less than 15 × 106 m3 of wood in Sweden, the model error is 1.62 × 106 m3, which is about 100 % of the observed damage. For years with big storms, such as Gudrun in 2005, the model error increased to 5.05 × 106 m3, which is between 10 and 50 % of the observed damage. When the same model parameters were used over France, the model reproduced a decrease in leaf area index and an increase in albedo, in accordance with SPOT-VGT and MODIS records following the passing of Cyclone Klaus in 2009. The current version of ORCHIDEE-CAN (revision 4262) is therefore expected to have the capability to capture the dynamics of forest structure due to storm disturbance on both regional and global scales, although the empirical parameters calculating gustiness from the gridded wind fields and storm damage from critical wind speeds may benefit from regional fitting.

Canopy structure is one of the most important vegetation characteristics for land–atmosphere interactions, as it determines the energy and scalar exchanges between the land surface and the overlying air mass. In this study we evaluated the performance of a newly developed multi-layer energy budget in the ORCHIDEE-CAN v1.0 land surface model (Organising Carbon and Hydrology In Dynamic Ecosystems – CANopy), which simulates canopy structure and can be coupled to an atmospheric model using an implicit coupling procedure. We aim to provide a set of acceptable parameter values for a range of forest types. Top-canopy and sub-canopy flux observations from eight sites were collected in order to conduct this evaluation. The sites crossed climate zones from temperate to boreal and the vegetation types included deciduous, evergreen broad-leaved and evergreen needle-leaved forest with a maximum leaf area index (LAI; all-sided) ranging from 3.5 to 7.0. The parametrization approach proposed in this study was based on three selected physical processes – namely the diffusion, advection, and turbulent mixing within the canopy. Short-term sub-canopy observations and long-term surface fluxes were used to calibrate the parameters in the sub-canopy radiation, turbulence, and resistance modules with an automatic tuning process. The multi-layer model was found to capture the dynamics of sub-canopy turbulence, temperature, and energy fluxes. The performance of the new multi-layer model was further compared against the existing single-layer model. Although the multi-layer model simulation results showed few or no improvements to both the nighttime energy balance and energy partitioning during winter compared with a single-layer model simulation, the increased model complexity does provide a more detailed description of the canopy micrometeorology of various forest types. The multi-layer model links to potential future environmental and ecological studies such as the assessment of in-canopy species vulnerability to climate change, the climate effects of disturbance intensities and frequencies, and the consequences of biogenic volatile organic compound (BVOC) emissions from the terrestrial ecosystem.

In Earth system modelling, a description of the energy budget of the vegetated surface layer is fundamental as it determines the meteorological conditions in the planetary boundary layer and as such contributes to the atmospheric conditions and its circulation. The energy budget in most Earth system models has been based on a big-leaf approach, with averaging schemes that represent in-canopy processes. Furthermore, to be stable, that is to say, over large time steps and without large iterations, a surface layer model should be capable of implicit coupling to the atmospheric model. Surface models with large time steps, however, have difficulties in reproducing consistently the energy balance in field observations. Here we outline a newly developed numerical model for energy budget simulation, as a component of the land surface model ORCHIDEE-CAN (Organising Carbon and Hydrology In Dynamic Ecosystems – CANopy). This new model implements techniques from single-site canopy models in a practical way. It includes representation of in-canopy transport, a multi-layer long-wave radiation budget, height-specific calculation of aerodynamic and stomatal conductance, and interaction with the bare-soil flux within the canopy space. Significantly, it avoids iterations over the height of the canopy and so maintains implicit coupling to the atmospheric model LMDz (Laboratoire de Météorologie Dynamique Zoomed model). As a first test, the model is evaluated against data from both an intensive measurement campaign and longer-term eddy-covariance measurements for the intensively studied Eucalyptus stand at Tumbarumba, Australia. The model performs well in replicating both diurnal and annual cycles of energy and water fluxes, as well as the vertical gradients of temperature and of sensible heat fluxes.

Because of the slow accumulation and long residence time of carbon in biomass and soils, the present state and future dynamics of temperate forests are influenced by management that took place centuries to millennia ago. Humans have exploited the forests of Europe for fuel, construction materials and fodder for the entire Holocene. In recent centuries, economic and demographic trends led to increases in both forest area and management intensity across much of Europe. In order to quantify the effects of these changes in forests and to provide a baseline for studies on future land-cover–climate interactions and biogeochemical cycling, we created a temporally and spatially resolved reconstruction of European forest management from 1600 to 2010. For the period 1600–1828, we took a supply–demand approach, in which supply was estimated on the basis of historical annual wood increment and land cover reconstructions. We made demand estimates by multiplying population with consumption factors for construction materials, household fuelwood, industrial food processing and brewing, metallurgy, and salt production. For the period 1829–2010, we used a supply-driven backcasting method based on national and regional statistics of forest age structure from the second half of the 20th century. Our reconstruction reproduces the most important changes in forest management between 1600 and 2010: (1) an increase of 593 000 km2 in conifers at the expense of deciduous forest (decreasing by 538 000 km2); (2) a 612 000 km2 decrease in unmanaged forest; (3) a 152 000 km2 decrease in coppice management; (4) a 818 000 km2 increase in high-stand management; and (5) the rise and fall of litter raking, which at its peak in 1853 resulted in the removal of 50 Tg dry litter per year.

Since 70 % of global forests are managed and forests impact the global carbon cycle and the energy exchange with the overlying atmosphere, forest management has the potential to mitigate climate change. Yet, none of the land-surface models used in Earth system models, and therefore none of today's predictions of future climate, accounts for the interactions between climate and forest management. We addressed this gap in modelling capability by developing and parametrising a version of the ORCHIDEE land-surface model to simulate the biogeochemical and biophysical effects of forest management. The most significant changes between the new branch called ORCHIDEE-CAN (SVN r2290) and the trunk version of ORCHIDEE (SVN r2243) are the allometric-based allocation of carbon to leaf, root, wood, fruit and reserve pools; the transmittance, absorbance and reflectance of radiation within the canopy; and the vertical discretisation of the energy budget calculations. In addition, conceptual changes were introduced towards a better process representation for the interaction of radiation with snow, the hydraulic architecture of plants, the representation of forest management and a numerical solution for the photosynthesis formalism of Farquhar, von Caemmerer and Berry. For consistency reasons, these changes were extensively linked throughout the code. Parametrisation was revisited after introducing 12 new parameter sets that represent specific tree species or genera rather than a group of often distantly related or even unrelated species, as is the case in widely used plant functional types. Performance of the new model was compared against the trunk and validated against independent spatially explicit data for basal area, tree height, canopy structure, gross primary production (GPP), albedo and evapotranspiration over Europe. For all tested variables, ORCHIDEE-CAN outperformed the trunk regarding its ability to reproduce large-scale spatial patterns as well as their inter-annual variability over Europe. Depending on the data stream, ORCHIDEE-CAN had a 67 to 92 % chance to reproduce the spatial and temporal variability of the validation data.

Functional relationships between wood density and measures of xylem hydraulic safety and efficiency are ambiguous, especially in wet tropical forests. In this meta-analysis, we move beyond wood density per se and identify relationships between xylem allocated to fibers, parenchyma, and vessels and measures of hydraulic safety and efficiency. We analyzed published data of xylem traits, hydraulic properties and measures of drought resistance from neotropical tree species retrieved from 346 sources. We found that xylem volume allocation to fiber walls increases embolism resistance, but at the expense of specific conductivity and sapwood capacitance. Xylem volume investment in fiber lumen increases capacitance, while investment in axial parenchyma is associated with higher specific conductivity. Dominant tree taxa from wet forests prioritize xylem allocation to axial parenchyma at the expense of fiber walls, resulting in a low embolism resistance for a given wood density and a high vulnerability to drought-induced mortality. We conclude that strong trade-offs between xylem allocation to fiber walls, fiber lumen, and axial parenchyma drive drought resistance in neotropical trees. Moreover, the benefits of xylem allocation to axial parenchyma in wet tropical trees might not outweigh the consequential low embolism resistance under more frequent and severe droughts in a changing climate., (© 2019 The Authors. Plant, Cell & Environment published by John Wiley & Sons Ltd.)

The Paris Agreement promotes forest management as a pathway towards halting climate warming through the reduction of carbon dioxide (CO 2 ) emissions 1 . However, the climate benefits from carbon sequestration through forest management may be reinforced, counteracted or even offset by concurrent management-induced changes in surface albedo, land-surface roughness, emissions of biogenic volatile organic compounds, transpiration and sensible heat flux 2-4 . Consequently, forest management could offset CO 2 emissions without halting global temperature rise. It therefore remains to be confirmed whether commonly proposed sustainable European forest-management portfolios would comply with the Paris Agreement-that is, whether they can reduce the growth rate of atmospheric CO 2 , reduce the radiative imbalance at the top of the atmosphere, and neither increase the near-surface air temperature nor decrease precipitation by the end of the twenty-first century. Here we show that the portfolio made up of management systems that locally maximize the carbon sink through carbon sequestration, wood use and product and energy substitution reduces the growth rate of atmospheric CO 2 , but does not meet any of the other criteria. The portfolios that maximize the carbon sink or forest albedo pass only one-different in each case-criterion. Managing the European forests with the objective of reducing near-surface air temperature, on the other hand, will also reduce the atmospheric CO 2 growth rate, thus meeting two of the four criteria. Trade-off are thus unavoidable when using European forests to meet climate objectives. Furthermore, our results demonstrate that if present-day forest cover is sustained, the additional climate benefits achieved through forest management would be modest and local, rather than global. On the basis of these findings, we argue that Europe should not rely on forest management to mitigate climate change. The modest climate effects from changes in forest management imply, however, that if adaptation to future climate were to require large-scale changes in species composition and silvicultural systems over Europe 5,6 , the forests could be adapted to climate change with neither positive nor negative  climate effects.

As the applications of Earth system models (ESMs) move from general climate projections toward questions of mitigation and adaptation, the inclusion of land management practices in these models becomes crucial. We carried out a survey among modeling groups to show an evolution from models able only to deal with land-cover change to more sophisticated approaches that allow also for the partial integration of land management changes. For the longer term a comprehensive land management representation can be anticipated for all major models. To guide the prioritization of implementation, we evaluate ten land management practices-forestry harvest, tree species selection, grazing and mowing harvest, crop harvest, crop species selection, irrigation, wetland drainage, fertilization, tillage, and fire-for (1) their importance on the Earth system, (2) the possibility of implementing them in state-of-the-art ESMs, and (3) availability of required input data. Matching these criteria, we identify "low-hanging fruits" for the inclusion in ESMs, such as basic implementations of crop and forestry harvest and fertilization. We also identify research requirements for specific communities to address the remaining land management practices. Data availability severely hampers modeling the most extensive land management practice, grazing and mowing harvest, and is a limiting factor for a comprehensive implementation of most other practices. Inadequate process understanding hampers even a basic assessment of crop species selection and tillage effects. The need for multiple advanced model structures will be the challenge for a comprehensive implementation of most practices but considerable synergy can be gained using the same structures for different practices. A continuous and closer collaboration of the modeling, Earth observation, and land system science communities is thus required to achieve the inclusion of land management in ESMs., (© 2017 John Wiley & Sons Ltd.)

Afforestation and forest management are considered to be key instruments in mitigating climate change. Here we show that since 1750, in spite of considerable afforestation, wood extraction has led to Europe's forests accumulating a carbon debt of 3.1 petagrams of carbon. We found that afforestation is responsible for an increase of 0.12 watts per square meter in the radiative imbalance at the top of the atmosphere, whereas an increase of 0.12 kelvin in summertime atmospheric boundary layer temperature was mainly caused by species conversion. Thus, two and a half centuries of forest management in Europe have not cooled the climate. The political imperative to mitigate climate change through afforestation and forest management therefore risks failure, unless it is recognized that not all forestry contributes to climate change mitigation., (Copyright © 2016, American Association for the Advancement of Science.)

Will species that are sensitive/tolerant to Zn pollution still have the same sensitivity/tolerance in a future climate? To answer this question we analysed the response of constructed grassland communities to five levels of zinc (Zn) supply, ranging from 0 to 354 mg Zn kg(-1) dry soil, under a current climate and a future climate (elevated CO2 and warming). Zn concentrations increased in roots and shoots with Zn addition but this increase did not differ between climates. Light-saturated net CO2 assimilation rate (A(sat)) of the species, on the other hand, responded differently to Zn addition depending on climate. Still, current and future climate communities have comparable biomass responses to Zn, i.e., no change in root biomass and a 13% decrease of above-ground biomass. Provided that the different response of A(sat) in a future climate will not compromise productivity and survival on the long term, sensitivity is not altered by climate change., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Objective: We aimed to assess whether executive functioning improved over time in a sample of borderline personality disorder (BPD) subjects that took part in a quetiapine treatment trial., Methods: Performance on the following neurocognitive tasks was assessed at enrolment and at the end of the 12 weeks quetiapine treatment: Trail Making Task, Word Fluency Task and Tower of London Task. Forty-one BPD patients were recruited, of whom 32 completed the trial. An intention-to-treat analysis with a mixed linear model was applied., Results: The data show that participants significantly improved on most executive functioning measures. Patients' scores decreased significantly (mean [SD] difference; p-value) on the Trail Making Task Part A (11.7 [2.3]; p < 0.0001), Part B (51.8 [9.2]; p < 0.0001) and 'B minus A' (40.1 [8.2]; p < 0.0001), on a Phonological (15.9 [1.6]; p < 0.0001) and Semantic (9.8 [1.1]; p < 0.0001) Verbal Fluency tasks, and on the Tower of London total correct score (2.5 [0.4]; p < 0.0001), total move score (29.5 [4.5]; p < 0.0001) and total time (172.9 [35.8]; p < 0.0001)., Conclusions: In this study we have demonstrated that executive functioning in BPD is improved after treatment with quetiapine. Neurocognitive measures of executive functioning should be considered as valuable outcomes in the study of treatment efficacy in BPD., (Copyright (c) 2009 John Wiley & Sons, Ltd.)

Data on the efficacy of quetiapine in borderline personality disorder (BPD) are still scarce. We aimed to investigate the efficacy of quetiapine for impulsivity and a broad range of affective symptoms in BPD. In this 12-week open-label study, we included individuals with BPD who presented to psychiatric in- and outpatient services. After a gradual titration of quetiapine, a flexible dose (range, 100-800 mg) was administered. The main outcome measures consisted of the scores on patient-rated questionnaires (Barratt Impulsiveness Scale, Buss-Durkee Hostility Inventory, Affective Lability Scale, Spielberger State and Trait Anxiety Inventory, Spielberger State and Trait Anger Inventory, and Beck Depression Inventory) and on neurocognitive tasks related to impulsivity (Stroop Color Word Task and IOWA Gambling Task). A mixed linear model, correcting for age, sex, antidepressant use, and weeks in psychotherapy, was applied. Forty-one patients (34 females and 7 males; mean [SD] age, 27.0 [9.0] years) were enrolled in the study, 32 of which completed the trial. Patients' scores decreased significantly (mean [SD] difference; P value) on the Barratt Impulsiveness Scale (19.7 [2.0]; P < 0.0001), Buss-Durkee Hostility Inventory (11.5 [1.4]; P < 0.0001), Affective Lability Scale (0.75 [0.08]; P < 0.0001), Beck Depression Inventory (25.0 [1.7]; P < 0.0001), Spielberger State and Trait Anxiety Inventory state (19.9 [1.9]; P < 0.0001) and trait (20.8 [1.7]; P < 0.0001) subscale, and Spielberger State and Trait Anger Inventory state (7.3 [1.1]; P < 0.0001) and trait (10.1 [1.0]; P < 0.0001) subscale. In addition, patients showed significantly less inference on the Stroop Color Word Task and had more 'good choices' on the IOWA Gambling Task. These results suggest that quetiapine may be efficacious in the treatment of impulsivity and affective symptoms in BPD.

Vomiting and retching are behaviours that are part of the clinical manifestation of several disorders. Rarely, vomiting is actually tic and, when not recognized, may mislead physicians and other caregivers to erroneously diagnose a medical or psychiatric disorder without considering a tic-disorder. We report on an 18 year old male patient who demonstrated vomiting as main symptom. Initially, he was diagnosed with an eating disorder, bulimia nervosa purging type (DSM-IV TR). Firstly, he was not very able to suppress his vomiting, but later the vomiting became forced by putting fingers in his throat. This self-induced vomiting had a compulsive component and was performed after almost every meal. Psychiatric assessment disclosed a specific sequence of a premonitory epigastric feeling preceding the vomiting and relief after vomiting. History taking revealed that he had a childhood onset of motor tics (copropraxia which consisted of grabbing his genitalia, bilateral facial grimacing and sudden movements of the head) and phonic tics (sniffing and gargling). Furthermore, he had been treated with methylphenidate for a childhood diagnosis of Attention Deficit and Hyperactivity Disorder and suffered from obsessive-compulsive symptoms (OCS). His vomiting was considered a tic in the course of a Tourette syndrome. His score on the Yale Global Tic Severity Scale dropped from 74 at the first assessment to a score of 50 at week 4 of treatment with risperidone 0,5 mg/day and sertralin 25 mg/day. Sedation and sexual dysfunction occurred as adverse events. Vomiting as a tic is rare clinical manifestation, but this possibility should be considered when patients have a history of tics.

In view of the projected climatic changes and the global decrease in plant species diversity, it is critical to understand the effects of elevated air temperature (T(air)) and species richness (S) on physiological processes in plant communities. Therefore, an experiment of artificially assembled grassland ecosystems, with different S (one, three or nine species), growing in sunlit climate-controlled chambers at ambient T(air) and ambient T(air) + 3 degrees C was established. We investigated whether grassland species would be more affected by midday high-temperature stress during summer in a warmer climate scenario. The effect of elevated T(air) was expected to differ with S. This was tested in the second and third experimental years by means of chlorophyll a fluorescence. Because acclimation to elevated T(air) would affect the plant's stress response, the hypothesis of photosynthetic acclimation to elevated T(air) was tested in the third year by gas exchange measurements in the monocultures. Plants in the elevated T(air) chambers suffered more from midday stress on warm summer days than those in ambient chambers. In absence of severe drought, the quantum yield of PSII was not affected by elevated T(air). Our results further indicate that species had not photosynthetically acclimated to a temperature increase of 3 degrees C after 3 years exposure to a warmer climate. Although effects of S and T(air) x S interactions were mostly not significant in our study, we expect that combined effects of T(air) and S would be important in conditions of severe drought events.

Purpose of Review: Compelling evidence suggests that a small group of men who develop schizophrenia display a stable pattern of antisocial behaviour from childhood onwards, causing considerable suffering to victims and to themselves and imposing a significant financial burden on society. We reviewed the literature on the neurobiological correlates of antisocial behaviour and violence to further the understanding of this subgroup of persons with schizophrenia and develop testable hypotheses for future research., Recent Findings: Few studies have been conducted, sample sizes are small and measures vary greatly. Taken together, the results suggest that among men with schizophrenia, those who have displayed a stable pattern of antisocial and aggressive behaviour since childhood, as compared with those with no such history, perform better on neuropsychological tests tapping specific executive functions and more poorly on assessments of orbitofrontal functions. We hypothesize that individuals in this subgroup are less compromised neurologically and display structural brain abnormalities in the amygdala-orbitofrontal system and in the prefrontal cortex and hippocampus., Summary: A better understanding of the distinctive neurobiological characteristics of this subgroup of men with schizophrenia will contribute to developing treatments tailored to their needs, to prevent antisocial behaviours and to reduce the symptoms of schizophrenia.

The Republic of Belarus (ROB) covers 207 600 km 2 and has a population of about 10 million (Ministry of Statistics and Analysis, 2005). It was a member state of the former Soviet Union until it gained independence in 1991. Belarus is located between Poland, Lithuania and Latvia in the west, Russia in the east, and Ukraine in the south. Seventy-two per cent of the population live in an urban environment and 28% in rural areas. The average life span for men is 63 years and for women 75 years (Ministry of Public Health, 2005).

Men and women who develop schizophrenia are at increased risk, compared with the general population, to engage in violence toward others. The reasons for this robust finding remain obscure. We undertook a review of studies comparing neuropsychological test performance, neurological soft signs, and structural brain images of persons with schizophrenia with and without a history of violence. Our search identified 17 studies. The results are inconsistent and contradictory, mainly due to varying definitions of violence, differences in sample characteristics, and the use of diverse measures to tap the neurobiological correlates of violent behavior. The results suggest, however, that among men with schizophrenia, those who have displayed a stable pattern of antisocial and aggressive behavior since childhood, as compared with those with no such history, perform better on neuropsychological tests tapping specific executive functions and more poorly on assessments of orbitofrontal functions, show fewer neurological soft signs, and display larger reductions in volume of the amygdalae, more structural abnormalities of the orbitofrontal system, more abnormalities of white matter in the amygdala-orbitofrontal system, and smaller reductions in volumes of the hippocampus.

Belgium has become one of the few countries in the world where euthanasia is legally allowed within a specific juridical framework. Even more unique is the inclusion of grounds for requesting euthanasia on the basis of mental suffering. Further refinement of the legal, medical and psychiatric approach to the issue is required in order to clear up essential practical and ethical matters. Psychiatrists and their professional organisations need to play a greater role in this ongoing debate and contribute from a clinical, scientific and ethical point of view.

A three-generation family is presented in which several relatives died from or are affected by idiopathic dilated cardiomyopathy (IDC). The transmission pattern is autosomal dominant. Although familial instances of IDC have been reported the proportion of familial cases tends to be underestimated. Moreover, different transmission patterns have been associated with IDC. This report adds further evidence to the fact that an autosomal dominant form of IDC clearly exists and that early screening of asymptomatic first degree relatives is mandatory for accurate genetic counselling of patients and their family members.