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Despite the evident challenges posed by arctic environments past and present, and despite the widespread acknowledgement that human population histories in the Arctic have historically been quite dynamic, it is often assumed that traditional pre-colonial populations were in perfect equilibrium with their environment, that they were perfectly adapted to their local environmental conditions. This adaptationist assumption is strongly challenged by recent research in ecology that has shown that many high-latitude ecological communities are in fact far from equilibrium with environmental conditions. Here we briefly introduce the notion of disequilibrium and the papers making up this special section. Ranging from the European Palearctic to the predicaments faced by contemporary populations in the circumpolar North, this collection presents a solid comparative evidence base for this new perspective. Together, these papers underline that adaptation - defined classically as the outcome of selection matching a particular feature or behaviour to the social or natural environment - cannot be assumed but needs to be empirically demonstrated. The papers also offer numerous qualitative and quantitative avenues for how to conduct such empirical investigations.

Emerging application areas such as air pollution in megacities, wind energy, urban security, and operation of unmanned aerial vehicles have intensified scientific and societal interest in mountain meteorology. To address scientific needs and help improve the prediction of mountain weather, the U.S. Department of Defense has funded a research effort—the Mountain Terrain Atmospheric Modeling and Observations (MATERHORN) Program—that draws the expertise of a multidisciplinary, multi-institutional, and multinational group of researchers. The program has four principal thrusts, encompassing modeling, experimental, technology, and parameterization components, directed at diagnosing model deficiencies and critical knowledge gaps, conducting experimental studies, and developing tools for model improvements. The access to the Granite Mountain Atmospheric Sciences Testbed of the U.S. Army Dugway Proving Ground, as well as to a suite of conventional and novel high-end airborne and surface measurement platforms, has provided an unprecedented opportunity to investigate phenomena of time scales from a few seconds to a few days, covering spatial extents of tens of kilometers down to millimeters. This article provides an overview of the MATERHORN and a glimpse at its initial findings. Orographic forcing creates a multitude of time-dependent submesoscale phenomena that contribute to the variability of mountain weather at mesoscale. The nexus of predictions by mesoscale model ensembles and observations are described, identifying opportunities for further improvements in mountain weather forecasting.

Made available in DSpace on 2014-12-03T13:08:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-08-07Bitstream added on 2014-12-03T13:24:38Z : No. of bitstreams: 1 WOS000323109700082.pdf: 1393704 bytes, checksum: 25bc393488fc34ae69a2e38b45a346c2 (MD5) NPRP grant from the Qatar National Research Fund (a member of Qatar foundation) NCF (Netherlands Computer Facility Foundation) NWO (Nederlandse Organisatie voor Wetenschappelijk Onderzoek) Odo van Vloten Foundation Over the past two decades, several fungal outbreaks have occurred, including the high-profile 'Vancouver Island' and 'Pacific Northwest' outbreaks, caused by Cryptococcus gattii, which has affected hundreds of otherwise healthy humans and animals. Over the same time period, C. gattii was the cause of several additional case clusters at localities outside of the tropical and subtropical climate zones where the species normally occurs. In every case, the causative agent belongs to a previously rare genotype of C. gattii called AFLP6/VGII, but the origin of the outbreak clades remains enigmatic. Here we used phylogenetic and recombination analyses, based on AFLP and multiple MLST datasets, and coalescence gene genealogy to demonstrate that these outbreaks have arisen from a highly-recombining C. gattii population in the native rainforest of Northern Brazil. Thus the modern virulent C. gattii AFLP6/VGII outbreak lineages derived from mating events in South America and then dispersed to temperate regions where they cause serious infections in humans and animals. CBS KNAW Fungal Biodivers Ctr, Dept Yeast & Basidiomycete Res, Utrecht, Netherlands Canisius Wilhelmina Hosp, Dept Med Microbiol & Infect Dis, Nijmegen, Netherlands Univ Sao Paulo State, Dept Phytopathol, UNESP, Ilha Solteira, Brazil Hadassah Hebrew Univ Med Ctr, Dept Clin Microbiol & Infect Dis, Jerusalem, Israel Univ Birmingham, Sch Biosci, Birmingham, W Midlands, England Univ Ghent, Fac Pharmaceut Sci, Lab Pharmaceut Biotechnol, B-9000 Ghent, Belgium Ctr Genom Regulat, Barcelona, Spain UPF Doctor Aiguader, Barcelona, Spain Netherlands Inst Ecol NIOO KNAW, Ctr Limnol, Wageningen, Netherlands Ctr Wiskunde & Informat, Amsterdam, Netherlands Vrije Univ Amsterdam, Dept Operat Res, Amsterdam, Netherlands Univ British Columbia, Sch Environm Hlth, Vancouver, BC V5Z 1M9, Canada Inst Nacl Salud, Microbiol Grp, Bogota, Colombia Fiocruz MS, Fundacao Oswaldo Cruz, Lab Micol, Inst Pesquisa Clin Evandro Chagas, BR-21045900 Rio De Janeiro, Brazil Univ Sydney, Westmead Hosp, Ctr Infect Dis & Microbiol,Sydney Emerging Dis &, Mol Mycol Res Lab,Westmead Millennium Inst,Sydney, Westmead, NSW 2145, Australia Radboud Univ Nijmegen, Med Ctr, Dept Med Microbiol, NL-6525 ED Nijmegen, Netherlands Second Mil Med Univ, Changzheng Hosp, Shanghai Key Lab Mol Med Mycol, Shanghai, Peoples R China Univ Med Ctr, Dept Internal Med & Infect Dis, Utrecht, Netherlands Univ Sao Paulo State, Dept Phytopathol, UNESP, Ilha Solteira, Brazil NPRP grant from the Qatar National Research Fund (a member of Qatar foundation)5-298-3-06

Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; Mycosphaerella blight caused by Mycosphaerella pinodes (Berk. and Blox.) Vestergr. is an important disease, causing severe damage in peas. Variability of 20 Algerian isolates of M. pinodes representative of four agro climatic regions were investigated on the basis of cultural, morphological and pathogenicity. Culture and morphology showed variations in colony color, radial growth pattern and production of pycnidia and pycnidiospores. Significant differences (P < 0.05) in both pycnidia and pycnidiospores size among isolates were observed. Hence, the size of pycnidia and pycnidiospores of M. pinodes varied from 145 x 143 mu m to 280 x 265 mu m and from 11.5 x 2.3 mu m to 22.5 x 6.3 mu m respectively. Using the factor analysis, this revealed that the first principal component (pc) was more related to the growth and sporulation aspect, hence, the colony growth and both the pycnidia and pycnidiospore density were more related to the first pc, while the second pc contributed for the pycnidiospores size. The isolates were also evaluated for their pathogenicity on seven cultivars in controlled conditions. Cluster analysis based on disease rating on a scale of 1 to 5, indicated higher similarity coefficient. In addition, using Euclidian distances method, the clusters were subdivided at 70% of similarity in seven pathotype groups (PG). The two first pathotypes grouped the most isolates (70%), representing isolates from the four agro climatic regions. However, the members of same group were different in their cultural and morphological characteristics. A detailed study to investigate molecular and genetic basis of diversity is suggested.

International audience; Micrometeorological measurements of nighttime ecosystem respiration can be systematically biased when stable atmospheric conditions lead to drainage flows associated with decoupling of air flow above and within plant canopies. The associated horizontal and vertical advective fluxes cannot be measured using instrumentation on the single towers typically used at micrometeorological sites. A common approach to minimize bias is to use a threshold in friction velocity, u*, to exclude periods when advection is assumed to be important, but this is problematic in situations when in-canopy flows are decoupled from the flow above. Using data from 25 flux stations in a wide variety of forest ecosystems globally, we examine the generality of a novel approach to estimating nocturnal respiration developed by van Gorsel et al. (van Gorsel, E., Leuning, R., Cleugh, H.A., Keith, H., Suni, T., 2007. Nocturnal carbon efflux: reconciliation of eddy covariance and chamber measurements using an alternative to the u*-threshold filtering technique. Tellus 59B, 397–403, Tellus, 59B, 307-403). The approach is based on the assumption that advection is small relative to the vertical turbulent flux (FC) and change in storage (FS) of CO2 in the few hours after sundown. The sum of FC and FS reach a maximum during this period which is used to derive a temperature response function for ecosystem respiration. Measured hourly soil temperatures are then used with this function to estimate respiration RRmax. The new approach yielded excellent agreement with (1) independent measurements using respiration chambers, (2) with estimates using ecosystem lightresponse curves of Fc + Fs extrapolated to zero light, RLRC, and (3) with a detailed process-based forest ecosystem model, Rcast. At most sites respiration rates estimated using the u*-filter, Rust, were smaller than RRmax and RLRC. Agreement of our approach with independent measurements indicates that RRmax provides an excellent estimate of nighttime ecosystem respiration