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1.
Genes (Basel) ; 13(3)2022 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-35328000

RESUMO

The lesser grain borer, Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae), is a major global pest of cereal grains. Infestations are difficult to control as larvae feed inside grain kernels, and many populations are resistant to both contact insecticides and fumigants. We sequenced the genome of R. dominica to identify genes responsible for important biological functions and develop more targeted and efficacious management strategies. The genome was assembled from long read sequencing and long-range scaffolding technologies. The genome assembly is 479.1 Mb, close to the predicted genome size of 480.4 Mb by flow cytometry. This assembly is among the most contiguous beetle assemblies published to date, with 139 scaffolds, an N50 of 53.6 Mb, and L50 of 4, indicating chromosome-scale scaffolds. Predicted genes from biologically relevant groups were manually annotated using transcriptome data from adults and different larval tissues to guide annotation. The expansion of carbohydrase and serine peptidase genes suggest that they combine to enable efficient digestion of cereal proteins. A reduction in the copy number of several detoxification gene families relative to other coleopterans may reflect the low selective pressure on these genes in an insect that spends most of its life feeding internally. Chemoreceptor genes contain elevated numbers of pseudogenes for odorant receptors that also may be related to the recent ontogenetic shift of R. dominica to a diet consisting primarily of stored grains. Analysis of repetitive sequences will further define the evolution of bostrichid beetles compared to other species. The data overall contribute significantly to coleopteran genetic research.


Assuntos
Besouros , Inseticidas , Aclimatação , Animais , Besouros/genética , Dominica , Larva/genética
2.
PLoS One ; 16(11): e0258735, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34731205

RESUMO

The Caribbean is a genetically diverse region with heterogeneous admixture compositions influenced by local island ecologies, migrations, colonial conflicts, and demographic histories. The Commonwealth of Dominica is a mountainous island in the Lesser Antilles historically known to harbor communities with unique patterns of migration, mixture, and isolation. This community-based population genetic study adds biological evidence to inform post-colonial narrative histories in a Dominican horticultural village. High density single nucleotide polymorphism data paired with a previously compiled genealogy provide the first genome-wide insights on genetic ancestry and population structure in Dominica. We assessed family-based clustering, inferred global ancestry, and dated recent admixture by implementing the fastSTRUCTURE clustering algorithm, modeling graph-based migration with TreeMix, assessing patterns of linkage disequilibrium decay with ALDER, and visualizing data from Dominica with Human Genome Diversity Panel references. These analyses distinguish family-based genetic structure from variation in African, European, and indigenous Amerindian admixture proportions, and analyses of linkage disequilibrium decay estimate admixture dates 5-6 generations (~160 years) ago. African ancestry accounts for the largest mixture components, followed by European and then indigenous components; however, our global ancestry inferences are consistent with previous mitochondrial, Y chromosome, and ancestry marker data from Dominica that show uniquely higher proportions of indigenous ancestry and lower proportions of African ancestry relative to known admixture in other French- and English-speaking Caribbean islands. Our genetic results support local narratives about the community's history and founding, which indicate that newly emancipated people settled in the steep, dense vegetation along Dominica's eastern coast in the mid-19th century. Strong genetic signals of post-colonial admixture and family-based structure highlight the localized impacts of colonial forces and island ecologies in this region, and more data from other groups are needed to more broadly inform on Dominica's complex history and present diversity.


Assuntos
Genética Populacional , Genoma Humano/genética , Desequilíbrio de Ligação/genética , População Rural , Adolescente , Adulto , Dominica/epidemiologia , Feminino , Variação Genética/genética , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Índias Ocidentais/epidemiologia , Adulto Jovem
3.
BMC Genomics ; 22(1): 65, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33472593

RESUMO

BACKGROUND: The lesser grain borer, Rhyzopertha dominica is a serious pest of stored grains. Fumigation and contact insecticides play a major role in managing this pest globally. While insects are developing genetic resistance to chemicals, hormonal analogues such as s-methoprene play a key role in reducing general pest pressure as well as managing pest populations that are resistant to fumigants and neurotoxic contact insecticides. However, resistance to s-methoprene has been reported in R. dominica with some reports showing a remarkable high resistance, questioning the use of this compound and other related analogues in grain protection. The current study attempts to identify possible molecular mechanisms that contribute in resistance to s-methoprene in R. dominica. RESULTS: Transcriptome analysis of resistant and susceptible strains of this pest species identified a set of differentially expressed genes related to cytochrome P450s, indicating their potential role in resistance to s-methoprene. Laboratory bioassays were performed with s-methoprene treated wheat grains in presence and absence of piperonyl butoxide (PBO), a cytochrome P450 inhibitor. The results indicate that PBO, when applied alone, at least at the concentration tested here, had no effect on R. dominica adult emergence, but has a clear synergistic effect to s-methoprene. The number of produced progeny decreased in presence of the inhibitor, especially in the resistant strain. In addition, we also identified CYP complement (CYPome) of R. dominica, annotated and analysed phylogenetically, to understand the evolutionary relationships with other species. CONCLUSIONS: The information generated in current study suggest that PBO can effectively be used to break resistance to s-methoprene in R. dominica.


Assuntos
Besouros , Inseticidas , Animais , Besouros/genética , Dominica , Perfilação da Expressão Gênica , Inseticidas/farmacologia , Metoprene , Butóxido de Piperonila/farmacologia , Transcriptoma
4.
Disasters ; 45(3): 691-716, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32129911

RESUMO

Survey questionnaires were administered among populations affected by Super Typhoon Yolanda in the Philippines in 2013 and Hurricane Maria in Dominica in 2017 to test the efficacy of early warning systems in prompting residents to take appropriate action ahead of severe hazards. Both events were rare and extreme but occurred in locations that regularly experience less severe tropical cyclones. The research assessed if, how, and when residents received warnings, what instructions were given, and where and when people decided to seek safety. In both of the cases under review, residents were aware of the approaching storms, but critical information on their severity and potential impacts was either not received in time or not understood fully, resulting in low levels of evacuation and safety-seeking behaviour. This paper suggests that planning and public communication need to focus on the uncertainty surrounding the severity and multifaceted nature of tropical cyclones and accompanying hazards and their consequences.


Assuntos
Tempestades Ciclônicas , Planejamento em Desastres/organização & administração , Desastres , Comunicação , Dominica , Abrigo de Emergência/estatística & dados numéricos , Humanos , Filipinas , Inquéritos e Questionários
5.
Pest Manag Sci ; 77(3): 1245-1255, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33051965

RESUMO

BACKGROUND: Phosphine-susceptible or resistant populations of Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) and Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae) adults were exposed to 0 (control), 1000 and 3000 ppm of phosphine for 15 or 90 min, to estimate behavioral and mobility responses after exposure to phosphine. Knockdown of the exposed individuals after exposure was recorded visually. The total distance moved and velocity of movement were assessed immediately after exposure to phosphine, 2 or 24 h later using a camera coupled with automated video tracking software (i.e. Ethovision®). RESULTS: For both species tested, the highest percentage of dead adults was noted at the highest concentration (3000 ppm) for both exposure times. For T. castaneum, total distance moved and velocity decreased as the concentration increased for the susceptible population, whereas there was significant variation among individuals in the resistant population. For R. dominica, the distance moved was reduced at the highest concentrations. Individuals of R. dominica moved less than those of T. castaneum and there were significant differences in mobility between susceptible and resistant populations for both species tested. Recovery was much faster in the case of the resistant populations. CONCLUSIONS: Changes in movement parameters can be further exploited in assessing the efficacy of different management tactics, such as trapping and sampling. Automated video tracking systems such as Ethovision® can be used to track and record insect behavioral response, providing a more objective measure of insecticide efficacy than visual categorizations. These data shed light on insect mobility and behavioral responses to fumigation treatments in relation to resistance. © 2020 Society of Chemical Industry.


Assuntos
Besouros , Inseticidas , Fosfinas , Tribolium , Animais , Dominica , Humanos , Insetos , Resistência a Inseticidas , Inseticidas/farmacologia , Software
7.
Artigo em Inglês | MEDLINE | ID: mdl-32933140

RESUMO

The present study investigates the interaction between cannabidiol (CBD) oil and three biopesticides: Azatin and two baculovirus formulations (Madex and Helicovex), both separately and in combination, in order to investigate their interaction against adults of four major coleopteran stored-product pests: Sitophilus zeamais (Coleoptera: Curculionidae), Rhyzopertha dominica (Coleoptera: Bostrichidae), Prostephanus truncatus (Coleoptera: Bostrichidae) and Trogoderma granarium (Coleoptera: Dermestidae). CBD, which has been understudied for its insecticidal properties, was applied at three different doses (500, 1500 and 3000 ppm). The biopesticides were administered at 1500 ppm. Interactions in the combined treatments were mathematically estimated as not synergistic and mostly competitive except for the combined treatments of CBD (1500 and 3000 ppm) with Azatin (1500 ppm) which were marked by an additive interaction. In its individual application, CBD oil generated the highest insect mortality while its effect was clearly dose-dependent. The findings reveal a promising effect of CBD oil against these coleopterans which had not been previously tested together.


Assuntos
Canabidiol/toxicidade , Besouros/efeitos dos fármacos , Inseticidas/toxicidade , Praguicidas/toxicidade , Gorgulhos/efeitos dos fármacos , Animais , Dominica
8.
Genome ; 63(12): 583-595, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32853534

RESUMO

Cacao (Theobroma cacao L.), an introduced tree crop in Dominica, is important for foreign exchange earnings from fine or flavour cocoa. The genetic structure of farmed cacao in Dominica was examined to identify varieties for conservation, breeding, and propagation to improve their cocoa industry. Cacao trees (156) from 73 sites over seven geographical regions were genotyped at 192 single nucleotide polymorphism (SNP) markers. Identity, regional differentiation, phylogenetic, multi-variate, ancestry, and core collection analyses were performed. Farmed cacao germplasm had moderate gene diversity (He = 0.320 ± 0.005) from generally unique trees, but cocoa growing regions were genetically similar. Synonymous matching (16.3%) showed that some clonal material was supplied to farmers. Cacao trees were mainly mixed from Amelonado, Criollo, Iquitos, Contamana, and Marañon ancestries, with predominantly Amelonado-Criollo hybrids. Criollo ancestry, linked to fine or flavour cocoa, was found at more than 30% in 28 unique trees. Forty-five trees, containing the SNP diversity of cacao in Dominica, are recommended as a core germplasm collection. This study identifies promising trees for improving cocoa quality; provides genetic evidence that community, regional, or country-wide pooling would not compromise the exclusive fine or flavour cocoa industry; and discusses other implications towards improving the Dominican cocoa industry.


Assuntos
Cacau/classificação , Cacau/genética , Variação Genética , Polimorfismo de Nucleotídeo Único , Cruzamento , Dominica , Genótipo , Filogenia
9.
Geneva; World Health Organization; 2020-03-24.
em Inglês | WHO IRIS | ID: who-331608
10.
J Econ Entomol ; 113(3): 1519-1527, 2020 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-31901160

RESUMO

This study evaluated the fumigant ethanedinitrile (EDN) against the cigarette beetle, Lasioderma serricorne, and phosphine-resistant and susceptible lesser grain borer, Rhyzopertha dominica, life stages under laboratory conditions. Eggs of both species were the most susceptible stage to EDN. EDN is, therefore, a promising alternative because eggs are generally tolerant to most common fumigants. Lasioderma serricorne eggs were the most susceptible with an LC50 estimated of 50.4 ppm, followed by adults, pupae and larvae with LC50 values of 160.2, 192.5, and 446.6 ppm, respectively, after 24-h exposure at 25°C. Eggs of phosphine-susceptible (LC50 = 11.2 ppm) and resistant (LC50 = 12.0 ppm) R. dominica strains were more susceptible to EDN than were adults of both strains, with LC50 values of 27.7 and 36.0 ppm, respectively. Lasioderma serricorne mixed life stage cultures were completely controlled at concentrations ≥2,000 ppm at 24 h. Fumigation with 600 ppm was enough to suppress adult emergence in the case of the phosphine-susceptible R. dominica strain (USDA), while an average of only 4.0 adults emerged from the phosphine-resistant R. dominica strain (Belle Glade) compared with 514.3 adults in the control. Lasioderma serricorne was more tolerant to EDN than both R. dominica strains. EDN caused 61.8 and 68.2 % inhibition of R. dominica (USDA) cytochrome c oxidase activity at concentrations of 0.0038 and 0.0076 mM in vitro, respectively, and it did not inhibit its activity in the case of an in vivo assay. These results suggest that cytochrome c oxidase may not be the main target for EDN toxicity.


Assuntos
Besouros , Inseticidas , Animais , Dominica , Fumigação , Inseticidas/toxicidade , Nitrilas
11.
Pest Manag Sci ; 76(5): 1683-1690, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31749328

RESUMO

BACKGROUND: Rhyzopertha dominica is a serious pest of stored grains and many populations have resistance to the fumigant phosphine. Some populations contain beetles with a 'strong resistance' phenotype. Recent work found the LC50 values for two strong-resistant populations recently studied in North America, Belle Glade and Minneapolis were 100- and 595-fold higher, respectively, compared to LC50 of a lab-susceptible strain. Populations with 'weak-resistant' phenotypes had LC50 values 5- to 10-fold that of a susceptible strain. The work reported below aimed to determine the minimum phosphine concentrations and number of days of exposure needed to effectively control all life stages of representative weak- and strong-resistant strains, and then to recommend the treatment conditions needed to control strongly phosphine-resistant R. dominica in pest populations. RESULTS: A dose-mortality assay estimated that phosphine fumigation over 48 h using 730-870 ppm at 25° C would control adults of both strongly resistant R. dominica populations. Fumigations with mixed life stage cultures found 200 ppm killed all susceptible and weak-resistant beetles in 2 days, but the strong-resistant Minneapolis and Belle Glade strains had substantial survivors at 200 ppm. Furthermore, the Belle Glade strain had beetles that survived 1000 ppm in 2-day fumigations. The strong-resistant Belle Glade strain needed nearly 10 days at over 400 ppm to have acceptable levels of control. CONCLUSION: This study recommends protocols to manage strongly resistant R. dominica populations provided that a minimum phosphine concentration of 400 ppm be maintained at 25° C or higher for up to 10 days. © 2019 Society of Chemical Industry.


Assuntos
Besouros , Animais , Dominica , Resistência a Inseticidas , Inseticidas , América do Norte , Fosfinas
12.
J Med Entomol ; 57(2): 418-436, 2020 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-31746340

RESUMO

The discovery of a new species, Periglischrus empheresotrichus, was determined through a review of museum collections, as well as a field survey of ectoparasites of island bats. This new species parasitizes on two bat species of the genus Monophyllus Leach, the Greater Antillean Long-tongued bat Monophyllus redmani Leach and the Lesser Antillean Long-tongued bat Monophyllus plethodon Miller. The female, male, deuthonymphs, and protonymph are described and illustrated. P. empheresotrichus n. sp. has an insular distribution, we evaluated the morphological variation of the adult populations, and concluded that intra-specific variation is correlated both with host species and locality (island) in the West Indies.


Assuntos
Infestações por Ácaros/veterinária , Ácaros/classificação , Animais , Quirópteros , Cuba , Dominica , República Dominicana , Feminino , Guadalupe , Haiti , Especificidade de Hospedeiro , Jamaica , Masculino , Infestações por Ácaros/parasitologia , Ácaros/anatomia & histologia , Ácaros/crescimento & desenvolvimento , Ninfa/anatomia & histologia , Ninfa/classificação , Ninfa/crescimento & desenvolvimento
14.
PLoS Negl Trop Dis ; 13(10): e0007772, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31658267

RESUMO

BACKGROUND: Small island developing states (SIDS) in the Caribbean region are challenged with managing the health outcomes of a changing climate. Health and climate sectors have partnered to co-develop climate services to improve the management of emerging arboviral diseases such as dengue fever, for example, through the development of climate-driven early warning systems. The objective of this study was to identify health and climate stakeholder perceptions and needs in the Caribbean, with respect to the development of climate services for arboviruses. METHODS: Stakeholders included public decision makers and practitioners from the climate and health sectors at the regional (Caribbean) level and from the countries of Dominica and Barbados. From April to June 2017, we conducted interviews (n = 41), surveys (n = 32), and national workshops with stakeholders. Survey responses were tabulated, and audio recordings were transcribed and analyzed using qualitative coding to identify responses by research topic, country/region, and sector. RESULTS: Health practitioners indicated that their jurisdiction is currently experiencing an increased risk of arboviral diseases associated with climate variability, and most anticipated that this risk will increase in the future. National health sectors reported financial limitations and a lack of technical expertise in geographic information systems (GIS), statistics, and modeling, which constrained their ability to implement climate services for arboviruses. National climate sectors were constrained by a lack of personnel. Stakeholders highlighted the need to strengthen partnerships with the private sector, academia, and civil society. They identified a gap in local research on climate-arbovirus linkages, which constrained the ability of the health sector to make informed decisions. Strategies to strengthen the climate-health partnership included a top-down approach by engaging senior leadership, multi-lateral collaboration agreements, national committees on climate and health, and shared spaces of dialogue. Mechanisms for mainstreaming climate services for health operations to control arboviruses included climatic-health bulletins and an online GIS platform that would allow for regional data sharing and the generation of spatiotemporal epidemic forecasts. Stakeholders identified a 3-month forecast of arboviral illness as the optimal time frame for an epidemic forecast. CONCLUSIONS: These findings support the creation of interdisciplinary and intersectoral 'communities of practice' and the co-design of climate services for the Caribbean public health sector. By fostering the effective use of climate information within health policy, research and practice, nations will have greater capacity to adapt to a changing climate.


Assuntos
Aedes , Controle de Doenças Transmissíveis , Doenças Transmissíveis , Saúde Pública , Adolescente , Adulto , Aedes/virologia , Idoso , Animais , Infecções por Arbovirus/prevenção & controle , Barbados , Mudança Climática , Doenças Transmissíveis/epidemiologia , Atenção à Saúde , Dengue/prevenção & controle , Dengue/transmissão , Vetores de Doenças , Dominica , Feminino , Política de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Setor Público , Participação dos Interessados , Inquéritos e Questionários , Adulto Jovem
16.
Artigo em Inglês | MEDLINE | ID: mdl-31640167

RESUMO

Structural inequalities in the U.S. work environment place most immigrants in low paying, high-risk jobs. Understanding how work experiences and influence the health of different immigrant populations is essential to address disparities. This article explores how Brazilian and Dominican immigrants feel about their experiences working in the U.S. and how the relationship between work and culture might impact their health. In partnership with the Dominican Development Center and the Brazilian Worker Center, we held five cultural conversations (CCs) with Brazilians (n = 48) and five with Dominicans (n = 40). CCs are participatory, unstructured groups facilitated by representatives from or embedded in the community. Brazilian immigrants focused on physical health and the American Dream while Dominicans immigrants emphasized concerns about the influence of work on mental health. Dominicans' longer tenure in the U.S. and differences in how Brazilians and Dominicans are racialized in the region might account for the variation in perspectives between groups. Future studies should further investigate the relationship between health and how immigrants' work lives are shaped by culture, race and immigrant status.


Assuntos
Emigrantes e Imigrantes/psicologia , Trabalho/psicologia , Brasil , Dominica , Feminino , Nível de Saúde , Humanos , Masculino , Qualidade de Vida , Fatores Socioeconômicos , Estados Unidos
17.
Am J Phys Anthropol ; 170(3): 393-403, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31460671

RESUMO

OBJECTIVES: Body size and composition vary widely among individuals and populations, and long-term research in diverse contexts informs our understanding of genetic, cultural, and environmental impacts on this variation. We analyze longitudinal measures of height, weight, and body mass index (BMI) from a Caribbean village, estimating the extent to which these anthropometrics are shaped by genetic variance in a small-scale population of mixed ancestry. MATERIALS AND METHODS: Longitudinal data from a traditionally horticultural village in Dominica document height and weight in a non-Western population that is transitioning to increasingly Westernized lifestyles, and an 11-generation pedigree enables us to estimate the proportions of phenotypic variation in height, weight, and BMI attributed to genetic variation. We assess within-individual variation across growth curves as well as heritabilities of these traits for 260 individuals using Bayesian variance component estimation. RESULTS: Age, sex, and secular trends account for the majority of anthropometric variation in these longitudinal data. Independent of age, sex, and secular trends, our analyses show high repeatabilities for the remaining variation in height, weight, and BMI growth curves (>0.75), and moderate heritabilities (h2 height = 0.68, h2 weight = 0.64, h2 BMI = 0.49) reveal clear genetic signals that account for large proportions of the variation in body size observed between families. Secular trends show increases of 6.5% in height and 16.0% in weight from 1997 to 2017. DISCUSSION: This horticultural Caribbean population has transitioned to include more Westernized foods and technologies over the decades captured in this analysis. BMI varies widely between individuals and is significantly shaped by genetic variation, warranting future exploration with other physiological correlates and associated genetic variants.


Assuntos
Estatura/fisiologia , Peso Corporal/fisiologia , Desenvolvimento Infantil/fisiologia , Adolescente , Adulto , Antropologia Física , Antropometria , Índice de Massa Corporal , Criança , Pré-Escolar , Dominica/etnologia , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Adulto Jovem
18.
Environ Entomol ; 48(4): 784-791, 2019 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-31114850

RESUMO

The objectives of the study are to understand how naïve beetles disperse after emerging as an adult in a homogeneous resource patch. We compared the movement of adult male and female Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae) using a laboratory and a field-collected strain during the first 2 d after their emergence from the wheat kernel in which they developed. We first asked if naïve male and female beetles show any innate orientation pattern. Males showed an upward orientation bias during the first day, but not in the second, whereas females had a random pattern of orientation in both days of evaluation. No significant differences were observed between the two strains. Given that males release an aggregation pheromone, we next asked if the upward movement of males improved their ability to be found by a naïve female. The presence of a male, whether above or below a newly emerged female, changed the females' movement direction from random to bias towards the male. In contrast, free-walking males exhibited the same upward movement bias on the first day regardless of the position of the caged male. Only on the second day did male movement change to the opposite direction of the caged male. Here, we report differences between males and females' movement orientation strategies and their response to males producing aggregation pheromone within the grain mass. Our data may improve our understanding of pheromone attraction and help us to develop better monitoring and control tools.


Assuntos
Besouros , Animais , Dominica , Feminino , Masculino , Orientação , Feromônios , Triticum
19.
In. The University of the West Indies, Faculty of Medical Sciences. Faculty of Medical Sciences, Research Day. St. Augustine, Caribbean Medical Journal, March 21, 2019. .
Não convencional em Inglês | MedCarib, MedCarib | ID: biblio-1046261

RESUMO

Objective: To compare biomedical research productivity among selected CARICOM countries. Design and Methodology: Biomedical publications of the selected CARICOM countries (Bahamas, Barbados, Dominica, Guyana, Grenada, Haiti, Jamaica, Suriname, and Trinidad & Tobago) were retrieved using 'PubMed' and 'ScImago Journal & country Rank' (SJR) databases. The publications for each country were then normalized by factors such as total population, gross domestic product (GDP) and Internet usage rate. Results: Total number of papers published by all 9 countries was 7,281 and 8,378 in PubMed (1990- 2015) and SJR databases (1996-2017) respectively. Jamaica produced highest number of biomedical publications [PubMed: 3,928 (54%) and SJR: 2,850 (34%)]. However, when adjusted, Grenada had the highest research publications per million populations, per billion GDP and per 1,000 Internet users in both databases. For trend analysis, PubMed showed that Jamaica produced highest number of additional publications each year ­ on an average 4.8 followed by Trinidad & Tobago (4.4). According to SJR, Jamaica had also highest number of citations (42,311) and H-index (76) followed by Trinidad & Tobago (29,152 and 71). Barbados had the highest number of citations per document (24.9) followed by Haiti (18.4). Conclusion: There was a marked imbalance noted among the CARICOM countries in terms of biomedical research and publications. A CARICOM-wide research may be embarked to explore disparities in biomedical research productivity and thus formulate informed health policies to alleviate diseases and eradicate poverty.


Assuntos
Pesquisa Biomédica , Suriname , Bahamas , Trinidad e Tobago , Barbados , Região do Caribe/etnologia , Dominica , Guiana , Haiti , Jamaica
20.
Plant Biol (Stuttg) ; 21(4): 738-744, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30773824

RESUMO

Most angiosperms rely on animal pollination for reproduction, but the dependence on specific pollinator groups varies greatly between species and localities. Notably, such dependence may be influenced by both floral traits and environmental conditions. Despite its importance, their joint contribution has rarely been studied at the assemblage level. At two elevations on the Caribbean island of Dominica, we measured the floral traits and the relative contributions of insects versus hummingbirds as pollinators of plants in the Rubiaceae family. Pollinator importance was measured as visitation rate (VR) and single visit pollen deposition (SVD), which were combined to assess overall pollinator effectiveness (PE). In the wet and cool Dominican highland, we found that hummingbirds were relatively more frequent and effective pollinators than insects, whereas insects and hummingbirds were equally frequent and effective pollinators at the warmer and less rainy midelevation. Furthermore, floral traits correlated independently of environment with the relative importance of pollinators, hummingbirds being more important in plant species having flowers with long and wide corollas producing higher volumes of dilute nectar. Our findings show that both environmental conditions and floral traits influence whether insects or hummingbirds are the most important pollinators of plants in the Rubiaceae family, highlighting the complexity of plant-pollinator systems.


Assuntos
Aves , Insetos , Polinização , Rubiaceae/fisiologia , Altitude , Animais , Aves/fisiologia , Dominica , Flores/anatomia & histologia , Flores/fisiologia , Umidade , Insetos/fisiologia , Néctar de Plantas/fisiologia , Rubiaceae/anatomia & histologia , Temperatura
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