This paper presents two novel statistical analyses of multiblock data using the R language. It is designed for data organized in (K + 1) blocks (i.e., tables) consisting of a block of response variables to be explained by a large number of explanatory variables which are divided into K meaningful blocks. All the variables - explanatory and dependent - are measured on the same individuals. Two multiblock methods both useful in practice are included, namely multiblock partial least squares regression and multiblock principal component analysis with instrumental variables. The proposed new methods are included within the ade4 package widely used thanks to its great variety of multivariate methods. These methods are available on the one hand for statisticians and on the other hand for users from various fields in the sense that all the values derived from the multiblock processing are available. Some relevant interpretation tools are also developed. Finally the main results are summarized using overall graphical displays. This paper is organized following the different steps of a standard multiblock process, each corresponding to specific R functions. All these steps are illustrated by the analysis of real epidemiological datasets.
Abstract In many parts of the world, clean water has become increasingly scarce. Irrigation of agricultural land with treated wastewater is commonly used in response to water shortages but there is concern about the environmental fate and transport of contaminants present in the irrigation wastewater. This study aimed to examine the presence of wastewater sourced contaminants in soil and field grown corn (Zea mays) crops spray irrigated with treated wastewater. Soil, corn grain, leaves, and root...
The study established a baseline situation of fruit fly species (Diptera: Tephritidae), using biodiversity analysis in mango orchards scattered in different ecological zones from the South to the North of Togo in West Africa. The fruit fly capture device consisted of orchard monitoring traps using a dry bait, made of four types of parapheromones specific to the males of the species of fruit flies. The sorting and identification of fruit fly species were carried out in the laboratory using a bino...
Last. Lourdes Adamson(UC Davis: University of California, Davis)H-Index: 9
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Inter-individual immune variability is driven predominantly by environmental factors including exposure to chronic infectious agents such as cytomegalovirus (CMV). We investigated the effects of rhesus CMV (RhCMV) on composition and function of the immune system in young macaques. Within months of infection, RhCMV was associated with impressive changes in antigen presenting cells, T cells, and NK cells - and marked expansion of innate-memory CD8+ T cells. These cells express high levels of NKG2A...
Abstract Although fires have occurred in the Brazilian savannas (Cerrado) without human influence, current human activities are changing the fire regimes and negatively affects the vegetation resilience and recovery rates. Contrasting effects of fire on biodiversity and structure of vegetation in the Cerrado are dependent on fire frequency. Some anthropogenic fire regimes have increased fire frequency with shorter intervals between fires. However, the dynamics post-fire and the time needed for v...
Culture evolves in ways that are analogous to, but distinct from, genomes. Previous studies examined similarities between cultural variation and genetic variation (population history) at small scales within language families, but few studies have empirically investigated these parallels across language families using diverse cultural data. We report an analysis comparing culture and genomes from in and around northeast Asia spanning 11 language families. We extract and summarize the variation in...
#2Rick Kesseli(University of Massachusetts Boston)H-Index: 32
Weedy dandelions have a worldwide distribution and thrive in urban environments despite a lack of sexual reproduction throughout most of its range. North American dandelions, introduced from Eurasia, are believed to be primarily, if not exclusively, apomictic triploids. In some European populations, apomicts co-occur with diploid sexual individuals and hybridizations can create genetically unique apomicts, which may subsequently disperse and establish new populations globally. Using six nuclear ...
Last. Naomi B. Schwartz(UBC: University of British Columbia)H-Index: 14
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Leaf habit has been hypothesized to define a linkage between the slow-fast plant economic spectrum and the drought resistance-avoidance trade-off in tropical forests ('slow-safe versus fast-risky'). However, variation in hydraulic traits as a function of leaf habit has rarely been explored for a large number of species. We sampled leaf and branch functional traits of 97 tropical dry forest tree species from four sites to investigate whether patterns of trait variation varied consistently in rela...
Last. Damian Chmura(University of Bielsko-Biała)H-Index: 13
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Abstract Although species composition, species diversity and the frequency of epixylic bryophytes is quite well recognised in Central Europe, the patterns associated with their plant traits are still relatively unknown. The main objective of this study was to determine which plant traits best explain the colonization of coarse woody debris (CWD) by the bryophytes and associate them with environmental factors. Moreover, we wanted to examine whether there are internal guilds of epixylic liverworts...
Abstract null null Dams modify geomorphology, water quantity, quality and timing of stream flows affecting ecosystem functioning and aquatic biota. In this study, we addressed the structural and functional macroinvertebrate community alterations in different instream mesohabitats of two Portuguese rivers impaired by dams. We sampled macroinvertebrates in riffles, runs and pools of river sites downstream of the dams (i.e. regulated; n = 24) and in sites without the influence of the dams (i.e. unr...