Abstract:This study tested whether the reduction in the number of large-bodied seed dispersers is correlated with shifts in the taxonomic and functional (e.g. dispersal mode and seed size) traits of the seeding communities within small fragments of semi-deciduous forest, southern Mexico. In five fragments (2.3–640 ha) and one continuous forest site we sampled tree and seedling species in 40 (20 × 20 m) and 120 (3 × 3 m) plots respectively, and recorded the incidence (presence/absence) of the disperser fauna (three common large-birds and >500-g mammals). Tree and seedling species were categorized according to dispersal mode, seed size and whether they originated from local (i.e. from dropped) or immigrant (i.e. from actively dispersed) seeds. Fragment size negatively correlated with number of species of medium to large vertebrate seed-dispersers and number of seedlings of large-seeded species, but had no influence on functional traits of the adult-tree community. Between 41% and 61% of all seedlings were considered as immigrants and the proportion of immigrant seedlings of large-seeded tree species was negatively correlated with forest size. The results suggest that biased defaunation in small forest fragments may seriously reduce recruitment of large-seeded tree species (>1.4 cm length) dispersed by vertebrates, negatively affecting successional trajectories of small forest fragments.
Although long‐standing theory suggests that biotic variables are only relevant at local scales for explaining the patterns of species' distributions, recent studies have demonstrated improvements to species distribution models (SDMs) by incorporating predictor variables informed by biotic interactions. However, some key methodological questions remain, such as which kinds of interactions are permitted to include in these models, how to incorporate the effects of multiple interacting species, and how to account for interactions that may have a temporal dependence. We addressed these questions in an effort to model the distribution of the monarch butterfly Danaus plexippus during its fall migration (September–November) through Mexico, a region with new monitoring data and uncertain range limits even for this well‐studied insect. We estimated species richness of selected nectar plants (Asclepias spp.) and roosting trees (various highland species) for use as biotic variables in our models. To account for flowering phenology, we additionally estimated nectar plant richness of flowering species per month. We evaluated three types of models: climatic variables only (abiotic), plant richness estimates only (biotic) and combined (abiotic and biotic). We selected models with AICc and additionally determined if they performed better than random on spatially withheld data. We found that the combined models accounting for phenology performed best for all three months, and better than random for discriminatory ability but not omission rate. These combined models also produced the most ecologically realistic spatial patterns, but the modeled response for nectar plant richness matched ecological predictions for November only. These results represent the first model‐based monarch distributional estimates for the Mexican migration route and should provide foundations for future conservation work. More generally, the study demonstrates the potential benefits of using SDM‐derived richness estimates and phenological information for biotic factors affecting species distributions.
Based on our detailed observations in the field, completed with herbarium material of representatives of Hydrangea section Cornidia in southeastern Mexico and Central America, we found that Hydrangea steyermarkii Standley, in contrast to what has been assumed up to now, is restricted to the Tacaná Volcano on the border of Mexico and Guatemala. The majority of the specimens with reddish or whitish indument on their branches in South East Mexico and Central America, belonging to this nearly exclusively Neotropical Hydrangea clade, had been identified as such, but the characters of these collections do not coincide with the single type specimen of H. steyermarkii, neither with other individuals of this species growing in the type locality area. In fact, nearly all specimens of Mesoamerica that had been identified as this species belong to a new species with a relatively wide distribution, which we describe here. This new species is illustrated and compared with H. steyermarkii, of which we also provide an amended description and illustrations. Finally, on the basis of these two species we document previously suggested dioecism in this plant group, which not only has consequences for systematics and nomenclature in this clade, but also for conservation.
Background and Aims: The genus Hydrangea consists of approximately 200 taxa in Asia and America. Whereas the shrubby species from Asia and the USA, as well as the over 1000 hybrids and cultivars derived from these, are very well known because of their ornamental value, the Neotropical species are much less appreciated. Hydrangea section Cornidia, currently consisting of 13 accepted taxa, occurs from Mexico to Chile and Argentina, with one species in southeast Asia. Its representatives are root-climbing lianas which may grow up to 60 m high in the tree canopy of temperate to (sub)tropical forests. Extensive field work throughout their distribution area and study of herbarium specimens has resulted in the discovery of new taxa. We present here a revision of the ten currently known Mexican species.Methods: Field work was carried out in northwestern, central and southeastern Mexico, including exploration in areas where the genus had not been collected before. Detailed morphological and architectural studies of all species were carried out, based on living plants in their natural habitat, as well as on dried specimens from our own collections and all available herbarium material.Key results: Six Hydrangea species new to science are described here, including an identification key for the native species and one widely cultivated species, illustrations and distribution maps. Additionally, amended descriptions for two earlier described species are presented, as a result of which all currently known native Mexican Hydrangeas now dispose of a detailed morphological description.Conclusions: The genus Hydrangea exemplifies the lack of taxon-specific botanical collection activities in Mexico. The discovery of these new species is even more surprising taking into account the considerable size of these plants. All Mexican Hydrangea species are threatened, mainly due to deforestation and land use changes.
This study had two aims, first, to determine the expectancies of control over pain experience ('pain locus of control') of patients with primary fibromyalgia syndrome (PFS) and to compare them with other chronic rheumatic diseases. Second, to analyse the relationships between health status and locus of control. We applied the Multidimensional Health Locus of Control-Pain and the Arthritis Impact Measurement Scales (AIMS), by interviewing 137 out patients (32 PFS, 32 RA, 20 SLE, 22 AS and 31 OA). Data were analysed by ANOVA and partial correlation tests. PFS patients believed that their symptoms depended on uncontrollable events and that they could not influence their disease by themselves. PFS patients were the most disabled on the 'Affect' (P < or = 0.001) and 'Symptom' factors (P < or = 0.01). In the PFS group, patients who showed a 'Fate' locus of control orientation reported more disability on 'Affect' and 'Social Interaction' AIMS factors.
Hydrangea section Cornidia, currently consisting of 19 accepted taxa, occurs from Mexico to Chile and Argentina, with one species in southeast Asia. Its representatives are root-climbing lianas which may grow up to 60 m high in the tree canopy of temperate to (sub)tropical forests. Our extensive field work throughout its distribution area, study of herbarium specimens and ongoing molecular studies have resulted in the discovery of species new to science, as well as new insights into the circumscription of many taxa. We here present amended descriptions for seven Hydrangea species of Central and South America and discuss the taxonomical situation of two Colombian Hydrangeas, including an identification key, illustrations, and distribution maps. Field work was carried out in Costa Rica, Panama, Ecuador and Peru, including exploration in areas where the genus had not been collected before. These specimens and observations were complemented with the study of specimens of 41 herbaria of North, Central and South America, as well as Europe. Detailed morphological studies of all species were carried out, based on living plants in their natural habitat, as well as on dried specimens from our own collections and all available herbarium material. Type material was studied in detail for all species concerned. Based on an extensive number of morphological characters, combined with distribution patterns, phenological differences and ecological preferences, including molecular data in most cases, Hydrangea peruviana and H. oerstedii are clearly distinct taxa, as well as the other seven species mentioned here, which had been synonymized with either of these two species. The present study results in the recognition of 26 species in section Cornidia and exemplifies the urgent need for profound taxonomic studies in plants, as in many families we do not dispose of well-circumscribed units for conservation to mitigate the already occurring unprecedented loss of biodiversity.
Bacterial (bact)DNA is an immunogenic product that frequently translocates into the blood in cirrhosis. We evaluated bactDNA clearance in patients undergoing liver transplantation (LT) and its association with inflammation and clinically relevant complications. We prospectively included patients consecutively admitted for LT in a one-year follow-up study. We evaluated bactDNA before and during the first month after LT, quantifying cytokine response at 30 days. One hundred patients were included. BactDNA was present in the blood of twenty-six patients undergoing LT. Twenty-four of these showed bactDNA in the portal vein, matching peripheral blood-identified bactDNA in 18 cases. Thirty-four patients showed bactDNA in blood during the first month after LT. Median TNF-α and IL-6 levels one month after LT were significantly increased in patients with versus without bactDNA. Serum TNF-α at baseline was an independent risk factor for bactDNA translocation during the first month after LT in the multivariate analysis (Odds ratio (OR) 1.14 [1.04 to 1.29], P = 0.015). One-year readmission was independently associated with the presence of bactDNA during the first month after LT (Hazard ratio (HR) 2.75 [1.39 to 5.45], P = 0.004). The presence of bactDNA in the blood of LT recipients was not shown to have any impact on complications such as death, graft rejection, bacterial or CMV infections. The rate of bactDNA translocation persists during the first month after LT and contributes to sustained inflammation. This is associated with an increased rate of readmissions in the one-year clinical outcome after LT.
The Randia sepium is an extremely interesting species with its coriaceous medium-sized leaves glabrous and brilliant on both sides with 4-7 pairs of secondary nerves and terminal inflorescences, with medium-sized hirsute flowers and pubescent corolla lobes on both sides not having closely related taxon in the Mexican and Mesoamerican flora. All Randia species of these areas having coriaceous shiny leaves -e.g. R. cookii and R. chiapensis -are thorny small-leaved, nerveless, small-flowered ones with small glabrous, axillary or terminal solitary flowers. It is notable for its use, since it is applied as living fence in Chiapas (Mexico).
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