Central And South America (central + and_south_america)

Distribution by Scientific Domains


Selected Abstracts


Edible insects: Traditional knowledge or western phobia?

ENTOMOLOGICAL RESEARCH, Issue 5 2009
Alan L. YEN
Abstract With an increasing human population and environmental degradation, the world faces a major problem in providing adequate animal based proteins. Many traditional societies have used or still use insects as a protein source, while westernized societies are reluctant to use insects, despite being the major consumers of animal proteins. We now need to consider insects as a source of food for humans in a manner that acknowledges both the role of entomophagy in indigenous societies and the need for westernized societies to reduce the size of their environmental footprint with regard to food production. The situation on continents such as Africa, Asia, and Central and South America has some parallels to Australia in that there are two forces in operation: the sustainable traditional use of edible insects and the "westernization" of these societies leading to a movement away from entomophagy. However, the potential to reach a compromise is greater in these continents because entomophagy is already accepted. The major challenges will be establishing sustainable production systems that include food safety and security as well as environmental protection. Whether this will happen or not will depend upon: (i) a major change in attitude in westernized societies towards entomophagy; (ii) pressure to conserve remaining habitats in a sustainable manner; (iii) economic impetus to develop food production systems that include insects; and (iv) an acknowledgement that achieving adequate nutrition on a global basis will involve different diets in much of the developed world. [source]


Molecular characterization of adenovirus circulating in Central and South America during the 2006,2008 period

INFLUENZA AND OTHER RESPIRATORY VIRUSES, Issue 6 2009
Josefina García
Background, Human Adenoviruses are recognized pathogens, causing a broad spectrum of diseases. Serotype identification is critical for epidemiological surveillance, detection of new strains and understanding of HAdvs pathogenesis. Little data is available about HAdvs subtypes in Latin America. Methods, In this study, we have molecularly characterized 213 adenoviruses collected from ILI presenting patients, during 2006-08, in Central and South America. Results, Our results indicate that 161(76%) adenoviruses belong to subgroup C, 45 (21%) to subgroup B and 7 (3%) to subtype E4. [source]


Tinea imbricata or Tokelau

INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 7 2004
Alexandro Bonifaz MB
Tinea imbricata (TI) or Tokelau is a superficial mycosis caused by Trichophyton concentricum, an anthropophilic dermatophyte. It is endemic in some islands of the South Pacific (Polynesia), South-East Asia, Central and South America, and Mexico, and is most often seen in individuals living in primitive and isolated conditions. The skin lesions are characteristically concentric and lamellar (imbricata: in Latin, tiled) plaques of scale. Predisposing conditions include humidity, inheritance, and immunologic factors. The diagnosis is usually made on clinical grounds, supported by skin scrapings and culture. Tokelau is a chronic and highly relapsing disease and, although no first-line treatment exists, best results are obtained with oral griseofulvin and terbinafine and a topical combination of keratolytic ointments, such as Whitfield's. TI is a disease model that allows the correlation of a series of environmental, genetic, immunologic, and therapeutic conditions. [source]


A clonal cutaneous CD30+ lymphoproliferative eruption in a patient with evidence of past exposure to hepatitis E

INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 7 2000
Freddye M. Lemons-Estes CDR, MC USN
The patient was a 52-year-old white man who had worked in remote areas of the world during the past 2 years, including an extended period in rural areas of Central Africa and in Central and South America. He had no acute illnesses during the 2-year period except for rare, mild, upper respiratory tract infections. For approximately 1 year, however, he had developed recurrent, papular-vesicular, slightly painful lesions on the fingers and palms, that spontaneously healed over weeks to months ( Fig. 1). The patient had no other concurrent illnesses and no abnormal laboratory findings, except for positive enzyme-linked immunoabsorbent assay (ELISA) for immunoglobulin G (IgG) antibodies for hepatitis E virus (HEV) using a recombinant expressed HEV antigen (Genelabs Technologies, Inc., San Antonio). Prolonged treatment with minocycline did not appear to moderate the lesions. At approximately 2.5 years after the development of his first cutaneous lesion, however, the patient reported that he had had no new lesions for over 3 months. Figure 1. Vesicular ,lesion on the finger which regressed over a period of weeks A biopsy specimen showed an intraepidermal vesicle with prominent epidermal necrosis and reticular degeneration ( Fig. 2). Within the epidermis, there was a dense infiltrate of lymphoid cells. The majority of these cells were pleomorphic with prominent nucleoli and frequent mitotic figures ( Fig. 3). Sheets of atypical cells were found in the subjacent dermis. The infiltrate extended down into the reticular dermis. With extension into the dermis, the infiltrate became more polymorphous with more small lymphoid cells, large numbers of eosinophils, and some plasma cells located more deeply. Figure 2. Intraepidermal ,blister showing reticular degeneration and marked epidermotrophism of large atypical cells with extension into the dermis with a mixed infiltrate containing eosinophils and plasma cells (30×) Figure 3. Intraepidermal ,infiltrate of large atypical cells with extension into the dermis with a mixed infiltrate containing eosinophils and plasma cells (400×) Immunohistochemical stains for CD3 (DAKO), CD4 (Becton Dickinson), CD8 (Becton Dickinson), CD15 (LeuM1, Becton Dickinson), CD20 (L-26, DAKO), CD30 (Ber-H2, DAKO), CD45RO (UCHL1, DAKO), S-100 protein (DAKO), T-cell intracellular antigen (TIA) (Coulter), epithelial membrane antigen (EMA) (DAKO), KP-1 (CD68, DAKO), MAC-387 (DAKO), Epstein,Barr virus (EBV) latent membrane antigen-1 (LMP-1, DAKO), and EBV-encoded nuclear antigen 2 (EBNA2, DAKO) were performed on formalin-fixed tissue using the ABC method with DABA as the chromagen. CD3 showed diffuse membrane staining of the large atypical lymphoid cells, as well as the majority of the small lymphoid cells ( Fig. 4). CD4 showed positive membrane staining of the large atypical lymphoid cells and the majority of the small lymphoid cells. CD8 showed only scattered light membrane staining of small lymphoid cells. CD15 was negative, and CD20 showed foci of groups of small lymphoid cells mainly within the reticular dermis. CD30 showed positive membrane and paranuclear staining of the large atypical cells, most abundant within the epidermis and papillary dermis ( Fig. 5). CD45RO showed positive membrane staining of the large atypical cells and the majority of the small lymphoid cells. S-100 protein showed increased dendritic cells within the surrounding viable epidermis and the subjacent papillary dermis ( Fig. 6). TIA showed granular staining in the large atypical lymphoid cells and only rare staining in small lymphoid cells ( Fig. 7). EMA staining was essentially negative. KP-1 showed only scattered positive cells mainly in the lower papillary and the reticular dermis. MAC-387 showed membrane staining in the viable epidermis ( Fig. 8). LMP-1 and EBNA2 for EBV were negative within the lymphoid cells as well as within the overlying epidermis. Figure 4. Immunohistochemical ,staining for CD3 showing diffuse staining of lymphoid cells within the epidermis and dermis (150×) Figure 5. Immunohistochemical ,staining for CD30 showing membrane and paranuclear staining of large atypical lymphoid cells within the epidermis and papillary dermis (a, 150× b, 400×) Figure 6. Immunohistochemical ,staining for S-100 protein within the epidermis and in the papillary dermis (a, 150× b, 300×) Figure 7. Immunohistochemical ,granular staining of large atypical lymphoid cells for TIA (200×) Figure 8. Immunohistochemical ,staining for MAC-387 showing epidermal staining (100×) Gene rearrangement studies showed a ,-T-cell receptor gene rearrangement. The monoclonal band was detected with VJ1, VJ2, and D1J2 primer sets. The T-cell receptor , rearrangement assay has a sensitivity of 61% and a specificity of 94% for the detection of a monoclonal rearrangement in T-cell lymphomas for which amplifiable DNA can be recovered. Electron microscopy was performed on formalin-fixed material, positive-fixed with 2.5% phosphate-buffered glutaraldehyde and further with 1% osmium tetroxide by standard techniques. Intracellular, 50,60-nm, cytoplasmic, spherical, viral-like particles were identified ( Fig. 9). Figure 9. Electron ,microscopy showing 50,60-nm diameter, intracellular, viral-like particles (arrows) (70,000×) [source]


A possible case of coccidioidomycosis from the Los Muertos site, Tempe, Arizona

INTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 4 2006
D. H. Temple
Abstract Coccidioidomycosis is a fungal disease endemic to southwestern North America and parts of Central and South America. Coccidioidomycosis frequently disseminates to the human skeleton and produces mostly lytic skeletal lesions. However, this disease is infrequently described within archaeological populations. As a result, it is important to report potential cases in order to improve current understanding of the appearance and distribution of lesions resulting from coccidioidomycosis in archaeological specimens. This study describes skeletal lesions in an adult male recovered from the Los Muertos site, Tempe, Arizona (AD 500,1450). These lesions are present on the inferior border of the left scapular spine, the medial portion of the left first metacarpal head, and the medial portion of the right first metatarsal. The lesions are predominantly lytic with sclerotic and, in some cases, healed cortical bone distributed around their margins. Evidence of skeletal healing is recorded within the destructive focus of one lesion. Geographical information on pathogen endemism, overall lesion distribution, and agricultural-era Hohokom behaviour suggest that coccidioidomycosis is the most likely diagnostic option for these lesions. Mounting evidence for possible infections in the palaeopathological literature, combined with high frequencies of nutritional stress levels in endemic regions, suggests that coccidioidomycosis contributed at least moderately to morbidity in the American Southwest. Copyright © 2006 John Wiley & Sons, Ltd. [source]


Army ants in four forests: geographic variation in raid rates and species composition

JOURNAL OF ANIMAL ECOLOGY, Issue 3 2007
SEAN O'DONNELL
Summary 1The New World army ants are top predators in the litter of tropical forest, but no comprehensive studies exist on variation in assemblage-wide activity and species composition. We used standardized protocols to estimate foraging raid rates and species composition of army ant communities in four Neotropical forests. The study sites spanned approximately 10° latitude, with two sites each in Central and South America. 2We recorded a total of 22 species of army ants. The four sites varied in observed and estimated species richness. Species overlap was highest between the Central American sites, and lowest between the South American sites. 3Raid activity varied significantly among sites. Raid activity per kilometre of trail walks was over four times higher at the most active site (Sta. Maria, Venezuela) than at the least active site (Barro Colorado Island, Panama). Furthermore, each site showed a different diel pattern of activity. For example, raid activity was higher during daylight hours in Costa Rica, and higher at night in Venezuela. Raid activity relationships with ambient temperature also varied significantly among sites. 4The overall rate of army ant raids passing through 1 m2 plots was 0·73 raids per day, but varied among sites, from 0 raids per day (Panama) to 1·2 raids per day (Venezuela). 5Primarily subterranean species were significantly more abundant in Venezuela, and above-ground foragers that form large swarm fronts were least abundant in Panama. The site heterogeneity in species abundance and diel activity patterns has implications for army ant symbionts, including ant-following birds, and for the animals hunted by these top predators. [source]


Global patterns of plant diversity and floristic knowledge

JOURNAL OF BIOGEOGRAPHY, Issue 7 2005
Gerold Kier
Abstract Aims, We present the first global map of vascular plant species richness by ecoregion and compare these results with the published literature on global priorities for plant conservation. In so doing, we assess the state of floristic knowledge across ecoregions as described in floras, checklists, and other published documents and pinpoint geographical gaps in our understanding of the global vascular plant flora. Finally, we explore the relationships between plant species richness by ecoregion and our knowledge of the flora, and between plant richness and the human footprint , a spatially explicit measure of the loss and degradation of natural habitats and ecosystems as a result of human activities. Location, Global. Methods, Richness estimates for the 867 terrestrial ecoregions of the world were derived from published richness data of c. 1800 geographical units. We applied one of four methods to assess richness, depending on data quality. These included collation and interpretation of published data, use of species,area curves to extrapolate richness, use of taxon-based data, and estimates derived from other ecoregions within the same biome. Results, The highest estimate of plant species richness is in the Borneo lowlands ecoregion (10,000 species) followed by nine ecoregions located in Central and South America with , 8000 species; all are found within the Tropical and Subtropical Moist Broadleaf Forests biome. Among the 51 ecoregions with , 5000 species, only five are located in temperate regions. For 43% of the 867 ecoregions, data quality was considered good or moderate. Among biomes, adequate data are especially lacking for flooded grasslands and flooded savannas. We found a significant correlation between species richness and data quality for only a few biomes, and, in all of these cases, our results indicated that species-rich ecoregions are better studied than those poor in vascular plants. Similarly, only in a few biomes did we find significant correlations between species richness and the human footprint, all of which were positive. Main conclusions, The work presented here sets the stage for comparisons of degree of concordance of plant species richness with plant endemism and vertebrate species richness: important analyses for a comprehensive global biodiversity strategy. We suggest: (1) that current global plant conservation strategies be reviewed to check if they cover the most outstanding examples of regions from each of the world's major biomes, even if these examples are species-poor compared with other biomes; (2) that flooded grasslands and flooded savannas should become a global priority in collecting and compiling richness data for vascular plants; and (3) that future studies which rely upon species,area calculations do not use a uniform parameter value but instead use values derived separately for subregions. [source]


Mainland colonization by island lizards

JOURNAL OF BIOGEOGRAPHY, Issue 6 2005
Kirsten E. Nicholson
Abstract Aim, We investigate biogeographic relationships within the lizard genus Anolis Daudin, 1802 to test the hypothesis that the mainland (Central and South American) Norops-clade species descended from a West Indian Anolis ancestor. Previous hypotheses have suggested that close island relatives of mainland Norops species (the Cuban Anolis sagrei and Jamaican A. grahami series) represent over-water dispersal from a mainland ancestor. These previous hypotheses predict that the A. sagrei and A. grahami series should be phylogenetically nested within a Norops clade whose ancestral geography traces to the mainland. If Norops is West Indian in origin, then West Indian species should span the deepest phylogenetic divergences within the Norops clade. Location, Central and South America and West Indian islands. Methods, The phylogenetic relationships of Anolis lizards are reconstructed from aligned DNA sequences using both parsimony and Bayesian approaches. Hypotheses are tested in two ways: (1) by reconstructing the ancestral geographic location for the Norops clade using Pagel & Lutzoni's (2002) Bayesian approach, and (2) by testing alternative topological arrangements via Wilcoxon Signed-Ranks tests (Templeton, 1983) and Shimodaira,Hasegawa tests (Shimodaira & Hasegawa, 1999). Results, Our evidence supports an origin of mainland Norops anoles from a West Indian ancestor. A West Indian ancestor to the Norops clade is statistically supported, and alternatives to the biogeographic pattern [Cuban (Jamaican, Mainland)] are statistically rejected by Shimodaira,Hasegawa tests, although not by Wilcoxon Signed-Ranks tests. Main conclusions, Our data support the hypothesis of a West Indian origin for mainland Norops. This result contradicts previous hypotheses and suggests that island forms may be an important source for mainland biodiversity. [source]


The distribution,abundance (density) relationship: its form and causes in a tropical mammal order, Primates

JOURNAL OF BIOGEOGRAPHY, Issue 4 2005
A. H. Harcourt
Abstract Aim, Across a wide variety of organisms, taxa with high local densities (abundance) have large geographical ranges (distributions). We use primatology's detailed knowledge of its taxon to investigate the form and causes of the relationship in, unusually for macroecological analysis, a tropical taxon. Location, Africa, Central and South America, Asia, Madagascar. Methods, To investigate the form of the density,range relationship, we regressed local density on geographical range size, and also on female body mass, because in the Primates, density correlates strongly with mass. To investigate the biological causes of the relationship, we related (1) abundance (density × range size) and (2) residuals from the density,range regression lines to various measures of (i) resource use, (ii) reproductive rate and (iii) potential specialization. All data are from the literature. Analyses were done at the level of species (n = 140), genera (n = 60) and families/subfamilies (n = 17). We present various levels of results, including for all data, after omission of outlier data, after correction for phylogenetic dependence, and after Bonferroni correction of probabilities for multiple comparisons. Results, Regarding the form of the relationship, Madagascar primates are clear outliers (high densities in small ranges). Among the remaining three realms, the relation of density to range is weak or non-existent at the level of species and genera. However, it is strong, tight and linear at the level of families/subfamilies (r2 = 0.6, F1,10 = 19, P < 0.01). Although among primates, density is very significantly related to mass, at no taxonomic level is range size related to body mass. Consequently, removing the effects of mass makes little to no difference to density,range results. Regarding the biology of the relationship, only traits indicative of specialization are associated with abundance (meaning numbers): rare taxa are more specialized than are abundant taxa. The association is largely via range size, not density. Across families, no traits correlate significantly with the density,range relationship, nor with deviations from it, despite the strength of the relationship at this taxonomic level. Main conclusions, We suggest that in macroecology, analysis at taxonomic levels deeper than that of the relatively ephemeral species can be appropriate. We argue that the several purely methodological explanations for the positive density,range size relationship in primates can be rejected. Of the various biological hypotheses, those having to do with specialization,generalization seem the only applicable ones. The fact that the relationship is entirely via range size, not via density, means that while we might have a biology of range size, we do not yet have one of the density,geographical range relationship. It is probably time to search for multivariate explanations, rather than univariate ones. However, we can for the first time, for at least primates, suggest that any association of abundance or range size with specialization is via the number of different subtaxa, not the average degree of specialization of each subtaxon. The implication for conservation is obvious. [source]


Chemical composition and nutritive value of peach palm (Bactris gasipaes Kunth) in rats

JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 9 2005
Pascal Leterme
Abstract The peach palm (Bactris gasipaes Kunth) is the starchy fruit of a palm tree widely cultivated in Central and South America. The present study aimed at determining its chemical composition and its nutritive value in rats. The average chemical composition of 17 samples was as follows: 410 g kg,1 water and, in g kg,1 of dry matter (DM), 54 g crude protein, 114 g oil, 39 g neutral detergent fibre, 716 g starch, 21 g sugars and 18 g ash. The main variability was observed for the oil (60,180 g kg,1 DM) and starch (590,780 g DM) contents. The proteins contained, on average, in g kg,1 of proteins, 49 g lysine, 13 g methionine, 19 g cysteine, 39 g threonine and 7 g tryptophan. The mineral fraction contained, per kg DM: 1.0 g Ca, 0.8 g P, 0.6 g Mg, 0.3 g Na, 44 mg Fe, 4 mg Cu and 10 mg Zn. The digestibility of four peach palm genotypes was determined in rats fed a diet composed of 350 g kg,1 of peach palm and 650 g of a control diet based on maize and soybean meal. The digestibility of DM, energy, starch and protein of peach palm alone reached, on average 91, 87, 96 and 95%, respectively. No difference was observed between varieties, except for starch (p < 0.05). On average, peach palm contained 51 g of truly digestible protein kg,1 DM and 3.691 kcal digestible energy kg,1 DM. A growth trial was also carried out for 1 month on rats (initial weight: 78 g) fed a diet containing 0, 200, 400, 600 or 800 g peach palm kg,1, at the expense of a diet composed of maize starch and casein. The growth rate of the rats decreased (p < 0.05) as the peach palm concentration increased. The growth decrease was due to a decrease (p < 0.05) in DM intake and to the lower quality of the peach palm protein. It is concluded that peach palm is mainly an energy source for humans and animals. It is poor in protein and minerals but can be consumed in large amounts. Copyright © 2005 Society of Chemical Industry [source]


Periodontal diseases in Central and South America

PERIODONTOLOGY 2000, Issue 1 2002
Per Gjermo
First page of article [source]


Hierarchical modeling of genome-wide Short Tandem Repeat (STR) markers infers native American prehistory

AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2010
Cecil M. Lewis Jr.
Abstract This study examines a genome-wide dataset of 678 Short Tandem Repeat loci characterized in 444 individuals representing 29 Native American populations as well as the Tundra Netsi and Yakut populations from Siberia. Using these data, the study tests four current hypotheses regarding the hierarchical distribution of neutral genetic variation in native South American populations: (1) the western region of South America harbors more variation than the eastern region of South America, (2) Central American and western South American populations cluster exclusively, (3) populations speaking the Chibchan-Paezan and Equatorial-Tucanoan language stock emerge as a group within an otherwise South American clade, (4) Chibchan-Paezan populations in Central America emerge together at the tips of the Chibchan-Paezan cluster. This study finds that hierarchical models with the best fit place Central American populations, and populations speaking the Chibchan-Paezan language stock, at a basal position or separated from the South American group, which is more consistent with a serial founder effect into South America than that previously described. Western (Andean) South America is found to harbor similar levels of variation as eastern (Equatorial-Tucanoan and Ge-Pano-Carib) South America, which is inconsistent with an initial west coast migration into South America. Moreover, in all relevant models, the estimates of genetic diversity within geographic regions suggest a major bottleneck or founder effect occurring within the North American subcontinent, before the peopling of Central and South America. Am J Phys Anthropol 2010. © 2009 Wiley-Liss, Inc. [source]


Primary pulmonary coccidioidomycosis in China

RESPIROLOGY, Issue 4 2010
Fen LAN
ABSTRACT Coccidioidomycosis is a fungal infection endemic to south-west USA, north Mexico and parts of Central and South America. We report here a case of primary pulmonary coccidioidomycosis in a previously healthy 14-year-old boy in China, which is considered a non-endemic country. The patient had non-specific symptoms of pulmonary infection, including fever, non-productive cough and night sweats. Both spherules and endospores of Coccidioides immitis were seen histologically following transbronchial biopsy of a cavitary lesion. The patient was treated with amphotericin B and fluconazole. Follow up 6 months post discharge found that the patient made a good recovery. [source]


Y-chromosome biallelic polymorphisms and Native American population structure

ANNALS OF HUMAN GENETICS, Issue 4 2002
M.-C. BORTOLINI
It has been proposed that women had a higher migration rate than men throughout human evolutionary history. However, in a recent study of South American natives using mtDNA restriction fragment polymorphisms and Y-chromosome microsatellites we failed to detect a significant difference in estimates of migration rates between the sexes. As the high mutation rate of microsatellites might affect estimates of population structure, we now examine biallelic polymorphisms in both mtDNA and the Y-chromosome. Analyses of these markers in Amerinds from North, Central and South America agree with our previous findings in not supporting a higher migration rate for women in these populations. Furthermore, they underline the importance of genetic drift in the evolution of Amerinds and suggest the existence of a North to South gradient of increasing drift in the Americas. [source]


Early development of the silver catfish Rhamdia quelen (Quoy & Gaimard, 1824) (Pisces:Heptapteridae) from the São Francisco River Basin, Brazil

AQUACULTURE RESEARCH, Issue 2 2009
Marcelo Pimenta De Amorim
Abstract The silver catfish, Rhamdia quelen, is endemic to North, Central and South America with high aquaculture potential and wide acceptance in the market. Breeder fish were subjected to induced reproduction through hypophysation using a crude common carp pituitary extract. Egg characteristics, oocyte surface ultrastructure and histology of larval ontogenesis until whole yolk resorption were described for the first time for this species. Oocytes and semen were obtained by manual extrusion, and fertilization was conducted using the dry method. After fertilization, eggs were kept in incubators at 24 °C. The embryonic development was monitored using a stereomicroscope every 10 min until hatching. To analyse the larval development, larvae samples were collected from incubators daily until the fifth day, fixed in Bouin's fluid and subjected to routine histological techniques. The oocyte extrusion occurred 8 h after the second hormone dose at 26 °C. The oocytes were spherical, non-adhesive and yellow, with a diameter of 1471.75±47.63 ,m. Scanning electron microscopy revealed a thin jelly coat covering the zona radiata in the animal pole around the micropyle. The blastopore closure occurred within 8 h after fertilization, and the fertilization rate was 79.9±5.2% at 24 °C. Embryonic development was completed within 25 h 30 min after fertilization. The complete resorption of the yolk and the formation of the digestive system organs and the mouth opening occurred on the fifth day, indicating a need for exogenous feeding. The results of this study provide information important for improvement in R. quelen culture and management. [source]


Imperialism from Below: Informal Empire and the Private Sector in Nineteenth-Century Germany

AUSTRALIAN JOURNAL OF POLITICS AND HISTORY, Issue 3 2008
Matt Fitzpatrick
Far from being the product of atavistic feudal remnants within German society, nineteenth-century German imperialism stemmed from precisely the liberal milieu that had come to prominence during 1848-49. Through an analysis of imperialist texts dealing with Central and South America, and the social logic of these imperialist works, an understanding of the nature of private sector and civil society imperialistic projects emerges that sees liberal imperialists seeking out alternatives to statist solutions in the light of political blockages to their efforts. [source]


A comprehensive phylogeny of the bumble bees (Bombus)

BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2007
S. A. CAMERON
Bumble bees (Bombus Latreille) occupy a wide diversity of habitats, from alpine meadows to lowland tropical forest, yet they appear to be similar in morphology throughout their range, suggesting that behavioural adaptations play a more important role in colonizing diverse habitats. Notwithstanding their structural homogeneity, bumble bees exhibit striking inter- and intraspecific variation in colour pattern, purportedly the outcome of mimetic evolution. A robust phylogeny of Bombus would provide the framework for elucidating the history of their wide biogeographical distribution and the evolution of behavioural and morphological adaptations, including colour pattern. However, morphological studies of bumble bees have discovered too few phylogenetically informative characters to reconstruct a robust phylogeny. Using DNA sequence data, we report the first nearly complete species phylogeny of bumble bees, including most of the 250 known species from the 38 currently recognized subgenera. Bayesian analysis of nuclear (opsin, EF-1,, arginine kinase, PEPCK) and mitochondrial (16S) sequences results in a highly resolved and strongly supported phylogeny from base to tips, with clear-cut support for monophyly of most of the conventional morphology-based subgenera. Most subgenera fall into two distinct clades (short-faced and long-faced) associated broadly with differences in head morphology. Within the short-faced clade is a diverse New World clade, which includes nearly one-quarter of the currently recognized subgenera, many of which are restricted to higher elevations of Central and South America. The comprehensive phylogeny provides a firm foundation for reclassification and for evaluating character evolution in the bumble bees. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society, 2007, 91, 161,188. [source]


Biogeographical, ecological and morphological structure in a phylogenetic analysis of Ateleia (Swartzieae, Fabaceae) derived from combined molecular, morphological and chemical data

BOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2010
HELEN E. IRELAND
A phylogenetic analysis of combined morphological, chemical and ITS/5.8S sequence data reveals that species of Ateleia are often more genetically than morphologically divergent, and that species thought to be most closely related morphologically are distant relatives within the genus. Ateleia shows niche conservatism, with most species confined to seasonally dry tropical forest in Central America and the Caribbean, and fewer species in the same biome in South America. Four independent transitions to wet forests may have occurred in the genus. The estimated ages of Ateleia lineages spanning Central and South America are either older or younger than the estimated age of closure of the Isthmus of Panama. The older dates clearly suggest that over-water dispersal is responsible for the distribution of Ateleia that includes the Caribbean Islands. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 162, 39,53. [source]


Cutaneous larva migrans: clinical features and management of 44 cases presenting in the returning traveller

BRITISH JOURNAL OF DERMATOLOGY, Issue 3 2001
V. Blackwell
Background Cutaneous larva migrans (CLM) is the result of a nematode infection, and shows a characteristic creeping eruption. As travel to the tropics increases, many British citizens may be returning with this infection, which is often misdiagnosed or treated incorrectly. Objectives To perform a retrospective survey of 44 cases of CLM presenting to the Hospital for Tropical Diseases in London over the last 2 years. Methods Cases were reviewed with regard to patient characteristics, source of infection, source of referral, clinical features and therapy. Results Most infections were acquired in Africa (32%), the Caribbean (30%) and South-east Asia (25%), but also in Central and South America. There was a history of exposure to a beach in 95% of patients and the median duration of symptoms was 8 weeks (range 1,104). Lesions mainly affected the feet (39%), buttocks (18%) and abdomen (16%), but the lower leg, arm and face were also affected. Multiple lesions were seen in seven of 44 cases (16%). Laboratory abnormalities were absent in all patients. Of 44 patients seen, four needed no treatment, 28 were cured by a single course of treatment, 11 required a second course of therapy and one patient was treated three times. Thirty-one patients received oral albendazole 400 mg daily for 3,5 days and 24 were cured (77%). Five patients received 10% thiabendazole cream topically for 10 days and four were cured (80%). Four patients received oral thiabendazole 1·5 g daily for 3 days and all required further therapy. Conclusions In view of the range of treatment regimens recorded, a randomized controlled trial comparing topical and systemic therapies is warranted. [source]


Nutrients, diversity, and community structure of two phytotelm systems in a lower montane forest, Puerto Rico

ECOLOGICAL ENTOMOLOGY, Issue 3 2000
Barbara A. Richardson
Summary 1. Bromeliad and heliconia phytotelmata in the same forest area were compared in terms of their animal assemblages, nutrient inputs, and plant architecture. 2. For all major elements, nutrient inputs from canopy-derived debris and rainfall in bromeliads were significantly lower than those derived from decaying flower parts and plant secretions in heliconia bracts. Bromeliads contained significantly fewer organisms per unit volume of water and unit dry weight of organic matter than did heliconia inflorescences. They also contained a significantly lower animal biomass (199 mg DW from 15 bromeliads, 527 mg DW from 15 heliconia inflorescences). 3. Species richness was independent of abundance, demonstrating that, at least for small container habitats, higher abundance does not necessarily lead to a greater species richness. Communities were remarkably similar in patterns of relative abundance and species richness (23 spp. in bromeliads, 21 spp. in heliconia), probably due to functional similarities in plant architecture, with the two most abundant species comprising 60,62% of the total community. Coefficients of similarity were low because of marked differences in species assemblages. 4. Some taxa were phytotelm generalists but most showed a preference for one particular habitat, indicating differential selection in the choice of oviposition sites and larval development within the forest ecosystem. In common with many island communities, species richness was lower than that reported for these phytotelm habitats in mainland central and south America. [source]