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Developing 'climate smart forestry' (CSF) indicators in mountain forest regions requires collection and evaluation of local data and their attributes. Genetic resources are listed among the core indicators for forest biological diversity. This study is a report on the evaluation of the standing genetic diversity within and across 12 pure beech stands (Fagus sylvatica L.) established within the CLIMO (CLImate Smart Forestry in Mountain Regions) project, using nuclear microsatellite markers. The sampling sites were set along the species' distribution range, including the Balkan region and extending towards the Iberian Peninsula. Cores or leaves from 20 to 23 old, mature trees per plot were sampled for DNA analysis. Genetic diversity indices were high across the range ([H.sub.E] = 0.74-0.81) with the highest in the Bosnian Mountains. Genetic divergence increased significantly with the geographical distance (Mantel test: r = 0.81, p < 0.001). Most of the stands exhibited an excess of heterozygotes, with the highest value at the Hungarian site ([H.sub.O]/[H.sub.E] = 1.177), where beech persists close to the eastern xeric limit of the species' distribution. STRUCTURE revealed within-region differentiation in the Balkan Peninsula, where the Bulgarian stand was the most outstanding. The genetic parameters of each stand could be assessed as a resource for CSF indicators interpreted especially at the local level. Key words: Fagus sylvatica, heterozygosity, F statistics, geographical groups, environmental variables. Le developpement d'indicateurs de foresterie intelligente face au climat (FIFC) dans les regions forestieres montagneuses exige la collecte et revaluation de donnees locales et de leurs attributs. Les ressources genetiques sont considerees comme des indicateurs de base pour la diversite biologique de la foret. Cette etude est un rapport sur revaluation de la diversite genetique actuelle dans et parmi 12 peuplements purs de hetre commun (Fagus sylvatica L.) etablis dans le cadre du projet CLIMO (CLIMO (<>) a l'aide de marqueurs microsatellites nucleaires. Les sites d'echantillonnage ont ete etablis le long de l'aire de repartition de l'espece, incluant la region des Balkans et se prolongeant vers la peninsule iberique. Des carottes ou des feuilles prelevees sur 20 a 23 vieux arbres matures par place echantillon ont ete echantillonnees pour l'analyse de l'ADN. Les indices de diversite genetique etaient eleves ([H.sub.E] = 0,74-0,81) a travers l'aire de repartition; les plus eleves ont ete observes dans les montagnes de Bosnie. La divergence genetique augmentait significativement avec la distance geographique (test de Mantel : r = 0,81, p < 0,001). La plupart des peuplements avaient un exces d'heterozygotes : le site hongrois, ou le hetre persiste pres de la limite xerique orientale de l'aire de repartition de 1'espece, avait la valeur la plus elevee ([H.sub.O]/[H.sub.E] = 1,177). STRUCTURE a revele une differenciation au sein de la region dans la peninsule des Balkans, ou un peuplement bulgare etait le plus remarquable. Les parametres genetiques de chaque peuplement pouvaient etre evalues en tant ressource pour les indicateurs de FIFC interpretes particulierement a l'echelle locale. [Traduit par la Redaction] Mots-cles: Fagus sylvatica, heterozygotie, statistique F, groupes geographiques, variables environnementales., 1. Introduction Forests play an important role in the mitigation of the effects of climate change. Therefore, climate smart forestry (CSF) may significantly invigorate the positive effects of forests and [...]

Dilute nitrides based on GaAs constitute a family of compounds whose main characteristic is the band-gap tunability, depending on the nitrogen content. In this work we have focussed our attention on the indium free dilute nitrides, i.e. GaNAsSb with a bandgap of around 1.1 eV, to study the effects that doping has on the crystalline structure, electrical and optical properties of the material. For such purpose, p-doped and n-doped GaNAsSb layers were grown by molecular beam epitaxy and characterized using x-ray diffraction, spectroscopic ellipsometry and photoreflectance among other techniques. The GaNAsSb optical properties match the double band-anticrossing model which is the proposed one to explain the dilute nitride band structure. However, the determined optical bandgap value does not follow any trend with doping, neither with concentration nor type. This is related with doping effects on the crystalline quality and layer composition, thus inducing a Sb gradient along layer thickness together with variations in N and Sb concentrations for different doping levels. Besides these structural variations, the complex refraction index, Hall mobility and carrier concentration as a function of temperature have been determined for these GaNAsSb layers. [ABSTRACT FROM AUTHOR]

The productivity and functioning of mixed-species forests often differs from that of monocultures. However, the magnitude and direction of these differences are difficult to predict because species interactions can be modified by many potentially interacting climatic and edaphic conditions, stand structure and previous management. Process-based forest growth models could potentially be used to disentangle the effects of these factors and thereby improve our understanding of mixed forest functioning while facilitating their design and silvicultural management. However, to date, the predicted mixing effects of forest growth models have not been compared with measured mixing effects. In this study, 26 sites across Europe, each containing a mixture and monocultures of Fagus sylvatica and Pinus sylvestris , were used to calculate mixing effects on growth and yield and compare them with the mixing effects predicted by the forest growth model 3-PG mix . The climate and edaphic conditions, stand structures and ages varied greatly between sites. The model performed well when predicting the stem mass and total mass (and mixing effects on these components), with model efficiency that was usually >0.7. The model efficiency was lower for growth or smaller components such as foliage mass and root mass. The model was also used to predict how mixing effects would change along gradients in precipitation, temperature, potential available soil water, age, thinning intensity and soil fertility. The predicted patterns were consistent with measurements of mixing effects from published studies. The 3-PG model is a widely used management tool for monospecific stands and this study shows that 3-PG mix can be used to examine the dynamics of mixed-species stands and determine how they may need to be managed. [ABSTRACT FROM AUTHOR]

The mixing of tree species with complementary ecological traits may modify forest functioning regarding productivity, stability, or resilience against disturbances. This may be achieved by a higher heterogeneity in stand structure which is often addressed but rarely quantified. Here, we use 32 triplets of mature and fully stocked monocultures and mixed stands of Scots pine ( Pinus sylvestris L.) and European beech ( Fagus sylvatica L.) located along a productivity and water availability gradient through Europe to examine how mixing modifies the stand structure in terms of stand density, horizontal tree distribution pattern, vertical stand structure, size distribution pattern, and variation in tree morphology. We further analyze how site conditions modify these aspects of stand structure. For this typical mixture of a light demanding and shade tolerant species we show that (i) mixing significantly increases many aspects of structural heterogeneity compared with monocultures, (ii) mixing effects such as an increase of stand density and diversification of vertical structure and tree morphology are caused by species identity (additive effects) but also by species interactions (multiplicative effects), and (iii) superior heterogeneity of mixed stands over monocultures can increase from dry to moist sites. We discuss the implications for analyzing the productivity, for modelling and for the management of mixed species stands. [ABSTRACT FROM AUTHOR]

The work presents doping characteristics and properties of high Si-doped InGaAs epilayers lattice-matched to InP grown by low pressure metal-organic vapour phase epitaxy. Silane and disilane were used as dopant sources. The main task of investigations was to obtain heavily doped InGaAs epilayers suitable for usage as plasmon-confinement layers in the construction of mid-infrared InAlAs/InGaAs/InP quantum-cascade lasers (QCLs). It requires the doping concentration of 1×1019 cm-3 and 1×1020 cm-3 for lasers working at 9 μm and 5 μm, respectively. The electron concentration increases linearly with the ratio of gas-phase molar fraction of the dopant to III group sources (IV/III). The highest electron concentrations suitable for InGaAs plasmon-contact layers of QCL was achieved only for disilane. We also observed a slight influence of the ratio of gas-phase molar fraction of V to III group sources (V/III) on the doping efficiency. Structural measurements using high-resolution X-ray diffraction revealed a distinct influence of the doping concentration on InGaAs composition what caused a lattice mismatch in the range of -240 -+ -780 ppm for the samples doped by silane and disilane. It has to be taken into account during the growth of InGaAs contact layers to avoid internal stresses in QCL epitaxial structures. [ABSTRACT FROM AUTHOR]

Summary Multiple myeloma (MM), one of the most frequent haematological malignancies, significantly increases the risk of bacterial infections due to treatment‐related side effects, comorbidities and cancer‐induced immune deficiencies. Recently, CD71+ erythroid cells (CECs) have been identified as key immunomodulators in neonates and cancer patients, but their role in MM progression remains unclear. Using a murine MM model, closely resembling human disease, we observed that MM progression is associated with anaemia and an increase in immature CECs, which are characterized by elevated arginase 2 (ARG2) expression. These MM‐associated CECs suppress T‐cell proliferation, contributing to impaired immune responses. Notably, ARG2 deficiency in mice led to slower MM progression and improved survival. Furthermore, MM‐bearing mice exhibited higher susceptibility to Listeria monocytogenes infections, mirroring the increased infection risk in MM patients. Our findings suggest that ARG2‐expressing CECs play a critical role in MM‐associated immune suppression and infection susceptibility, pointing out ARG2 as a potential therapeutic target to enhance immune function and reduce infection risks in MM patients. [ABSTRACT FROM AUTHOR]

• Higher resilience and resistance to drought events in mixed stands compared to monospecifics. • Higher benefits of mixture in conifer-broadleaved stands. • The identity of the species mediates tree response to drought. • Increased resilience to drought in drier sites. • Complexity of the relationship between tree growth and drought confirmed. Despite growing evidence that diverse forests play an important role in ecosystem functioning, ensuring the provision of different ecosystem services, whether such diversity improves their response to drought events remains unclear. In this study, we use a large tree-ring database from thirty case studies across nine European countries and eleven species, covering from Mediterranean to hemiboreal forests, to test if the growth response to site specific drought events that occurred between 1975 and 2015 varied between mixed and monospecific stands. In particular, we quantify how stands resist those specific drought events and recover after them, thus analyzing their resilience. For each drought event and forest stand we calculated resistance, recovery, resilience and relative resilience and we related the variation in these indices between monospecific and mixed stands with type of admixture, tree species identity, site aridity gradient, stand basal area and stand age. We found a large variability among case studies, even for those that share similar species composition and have similar climates. On average, mixed stands showed higher resistance, resilience and relative resilience to drought events than monospecific stands. However, the beneficial effect of mixtures could not be generalized, being greatly modulated by the type of admixture and tree species identity, and depending on site water supply and stand characteristics, such as basal area and age. The increase in resilience in mixtures compared with monocultures was greater on the conifer-broadleaved admixtures, and to a lesser extent in the broadleaved-broadleaved combinations. The observed response patterns to drought largely varied among the eleven studied species, thus revealing the importance of functional traits for understanding a species' response to drought across its distribution range. Along the site aridity gradient, resilience and relative resilience to drought increased in drier sites for both monospecific and mixed stands, with an observed trend towards higher resilience in mixed stands in the drier and hotter sites. Our results confirm the complexity of the relationships found of resistance, recovery, resilience and relative resilience with drought when comparing pure vs mixed stands. [ABSTRACT FROM AUTHOR]

• Analysis of drought response patterns in mixed and monospecific stands along a wide ecological gradient across Europe. • Oak exhibits a higher average growth resistance and resilience than Scots pine. • Species mixing increases average drought resistance of Scots pine and resistance and resilience of oak. • Drought responses in mixtures and monocultures are dependent on tree size, site water supply and fertility. Tree species mixing has been widely promoted as a promising silvicultural tool for reducing drought stress. However, so far only a limited number of species combinations have been studied in detail, revealing inconsistent results. In this study, we analysed the effect of mixing Scots pine and oak (pedunculate oak and sessile oak) trees on their drought response along a comprehensive ecological gradient across Europe. The objective was to improve our knowledge of general drought response patterns of two fundamental European tree species in mixed versus monospecific stands. We focused on three null hypotheses: (HI) tree drought response does not differ between Scots pine and oak, (HII) tree drought response of Scots pine and oak is not affected by stand composition (mixture versus monoculture) and (HIII) tree drought response of Scots pine and oak in mixtures and monocultures is not modified by tree size or site conditions. To test the hypotheses, we analysed increment cores of Scots pine and oak, sampled in mixed and monospecific stands, covering a wide range of site conditions. We investigated resistance (the ability to maintain growth levels during drought), recovery (the ability to restore a level of growth after drought) and resilience (the capacity to recover to pre-drought growth levels), involving site-specific drought events that occurred between 1976 and 2015. In monocultures, oak showed a higher resistance and resilience than Scots pine, while recovery was lower. Scots pine in mixed stands exhibited a higher resistance, but also a lower recovery compared with Scots pine in monocultures. Mixing increased the resistance and resilience of oak. Ecological factors such as tree size, site water supply and site fertility were found to have significant effects on the drought response. In the case of Scots pine, resistance was increased by tree size, while recovery was lowered. Resistance of oak increased with site water supply. The observed mixing effect on the tree drought response of Scots pine and oak was in some cases modified by the site conditions studied. Positive mixing effects in terms of resistance and resilience of oak increased with site water supply, while the opposite was found regarding recovery. In contrast, site fertility lessened the positive mixing effect on the resistance of Scots pine. We hypothesise that the observed positive mixing effects under drought mainly result from water- and/or light-related species interactions that improve resource availability and uptake according to temporal and spatial variations in environmental conditions. [ABSTRACT FROM AUTHOR]

Objective To investigate associations of APOE and Tau gene polymorphisms with sports-related acute concussions and baseline to post-concussion neuropsychological test score changes. Design Multi-center prospective cohort study. Setting Scholarship athletes at 21 universities and 4 high schools Participants: 3218 athletes playing football (70%) or soccer (23%). Assessment of Risk Factors APOE, APOE G-219T promoter (APOEProm), Tau exon 6 Ser53Pro (TauSer), and Tau exon 6 Hist47Tyr (TauHis) genetic polymorphisms. Main Outcome Measurements (1) Acute concussions and (2) differences between baseline and 24–72 h post-concussion Headminder Neuropsychological Test Scores of Simple and Complex Reaction Time (SRT and CRT, respectively) and Processing Speed. Results There were a total of 131 athletes with incident concussions and genetic data and neuropsychological test scores. There were no statistically significant differences in frequencies of acute concussions according to genotypes by χ2 test. By t-test, the mean baseline to post-concussion neuropsychological changes were statistically significantly greater for CRT and SRT in those with the TauSer ‘TT’ genotype and for CRT in those with the APOEProm ‘TT’ genotype, and borderline significantly greater in those with the TauSer ‘TT’ genotype (p=0.09). Conclusions The statistically significantly worse mean baseline to post-concussion neuropsychological test scores in those with the APOEProm and TauSer polymorphisms suggests a possible genetic influence on post-concussion neurocognitive recovery. These preliminary findings provide no evidence for associations of the four APOE and Tau gene polymorphisms investigated with acute concussions, although the small sample size and lack of control for confounders are limitations. [ABSTRACT FROM AUTHOR]