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1.
Sci Data ; 10(1): 327, 2023 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-37236921

RESUMO

The Checklist of the Vascular Plants of the Republic of Guinea (CVPRG) is a specimen-based, expert-validated knowledge product, which provides a concise synthesis and overview of current knowledge on 3901 vascular plant species documented from Guinea (Conakry), West Africa, including their accepted names and synonyms, as well as their distribution and status within Guinea (indigenous or introduced, endemic or not). The CVPRG is generated automatically from the Guinea Collections Database and the Guinea Names Backbone Database, both developed and maintained at the Royal Botanic Gardens, Kew, in collaboration with the staff of the National Herbarium of Guinea. A total of 3505 indigenous vascular plant species are reported of which 3328 are flowering plants (angiosperms); this represents a 26% increase in known indigenous angiosperms since the last floristic overview. Intended as a reference for scientists documenting the diversity and distribution of the Guinea flora, the CVPRG will also inform those seeking to safeguard the rich plant diversity of Guinea and the societal, ecological and economic benefits accruing from these biological resources.


Assuntos
Magnoliopsida , Traqueófitas , Guiné , Plantas
2.
Hosp Pediatr ; 12(11): 995-1001, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36226552

RESUMO

BACKGROUND AND OBJECTIVES: In a previous study of 204 transgender and gender diverse youth in our region, 44% reported being made to feel uncomfortable in the emergency department (ED) because of their gender identity. The objective of our study was to conduct a 2 year quality improvement project to increase affirmed name and pronoun documentation in the pediatric ED. METHODS: Using process mapping, we identified 5 key drivers and change ideas. The key driver diagram was updated as interventions were implemented over 3 Plan-Do-Study-Act cycles. Our primary outcome, the percentage of ED visits per month with pronouns documented, was plotted on a run chart with the goal of seeing a 50% increase in form completion from a baseline median of ∼14% over the 2 year study period. RESULTS: The frequency of pronoun documentation increased from a baseline median of 13.8% to a median of 47.8%. The most significant increase in pronoun documentation occurred in Plan-Do-Study-Act cycle 3, immediately after ED-wide dissemination of a near-miss case and subsequent call for improvement by ED leadership. Roughly 1.7% of all encounters during the study period involved patients whose pronouns were discordant from the sex listed in their electronic health record. CONCLUSIONS: This quality-improvement project increased the frequency of pronoun documentation in the ED. This has the potential to improve the quality of care provided to transgender and gender diverse youth in the ED setting and identify patients who may benefit from receiving a referral to a pediatric gender clinic for additional support.


Assuntos
Serviço Hospitalar de Emergência , Identidade de Gênero , Criança , Adolescente , Humanos , Feminino , Masculino , Documentação , Melhoria de Qualidade , Registros Eletrônicos de Saúde
3.
Biol Rev Camb Philos Soc ; 96(1): 16-51, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32924323

RESUMO

Tropical Africa is home to an astonishing biodiversity occurring in a variety of ecosystems. Past climatic change and geological events have impacted the evolution and diversification of this biodiversity. During the last two decades, around 90 dated molecular phylogenies of different clades across animals and plants have been published leading to an increased understanding of the diversification and speciation processes generating tropical African biodiversity. In parallel, extended geological and palaeoclimatic records together with detailed numerical simulations have refined our understanding of past geological and climatic changes in Africa. To date, these important advances have not been reviewed within a common framework. Here, we critically review and synthesize African climate, tectonics and terrestrial biodiversity evolution throughout the Cenozoic to the mid-Pleistocene, drawing on recent advances in Earth and life sciences. We first review six major geo-climatic periods defining tropical African biodiversity diversification by synthesizing 89 dated molecular phylogeny studies. Two major geo-climatic factors impacting the diversification of the sub-Saharan biota are highlighted. First, Africa underwent numerous climatic fluctuations at ancient and more recent timescales, with tectonic, greenhouse gas, and orbital forcing stimulating diversification. Second, increased aridification since the Late Eocene led to important extinction events, but also provided unique diversification opportunities shaping the current tropical African biodiversity landscape. We then review diversification studies of tropical terrestrial animal and plant clades and discuss three major models of speciation: (i) geographic speciation via vicariance (allopatry); (ii) ecological speciation impacted by climate and geological changes, and (iii) genomic speciation via genome duplication. Geographic speciation has been the most widely documented to date and is a common speciation model across tropical Africa. We conclude with four important challenges faced by tropical African biodiversity research: (i) to increase knowledge by gathering basic and fundamental biodiversity information; (ii) to improve modelling of African geophysical evolution throughout the Cenozoic via better constraints and downscaling approaches; (iii) to increase the precision of phylogenetic reconstruction and molecular dating of tropical African clades by using next generation sequencing approaches together with better fossil calibrations; (iv) finally, as done here, to integrate data better from Earth and life sciences by focusing on the interdisciplinary study of the evolution of tropical African biodiversity in a wider geodiversity context.


Assuntos
Biodiversidade , Ecossistema , Animais , Fósseis , Filogenia , Plantas/genética
4.
PLoS One ; 13(10): e0205354, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30321199

RESUMO

In the Alps phylogeographic studies indicate for small insect-pollinated herbs that climatic fluctuations caused significant population migrations and fragmentations into glacial refugia at the periphery of the Alps. Here we investigate whether this holds also for wind-pollinated and -dispersed species. We therefore analysed the phylogeographic pattern (nuclear and chloroplast dataset) of a clade of the four species of the Helictotrichon parlatorei species group (Poaceae) endemic to the Alps. In contrast to earlier findings for small insect-pollinated herbs no clear barriers to gene flow could be detected in this species group. Instead a few haplotypes are widespread across the entire Alpine region. While the complete absence of a phylogeographic structure in the plastid dataset hints towards very efficient long distance seed dispersal, the moderate phylogeographic structure in the nuclear dataset indicates at least some spatial restriction to pollen dispersal. Rare haplotypes cluster solely in the Western and Southern central Alps and thereby suggest this to be the area of origin for the H. parlatorei species group from where expansion occurred following the presence of calcareous bedrock into the Eastern Alps. We thus conclude that the inclusion of taxa with complementary life-history traits is vital in understanding the glacial history of the Alpine flora.


Assuntos
Filogeografia , Poaceae/genética , Polinização/genética , Especiação Genética , Haplótipos/genética , Filogenia , Poaceae/crescimento & desenvolvimento , Polinização/fisiologia , Refúgio de Vida Selvagem , Vento
5.
BMC Biol ; 15(1): 15, 2017 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-28264718

RESUMO

BACKGROUND: Understanding the patterns of biodiversity distribution and what influences them is a fundamental pre-requisite for effective conservation and sustainable utilisation of biodiversity. Such knowledge is increasingly urgent as biodiversity responds to the ongoing effects of global climate change. Nowhere is this more acute than in species-rich tropical Africa, where so little is known about plant diversity and its distribution. In this paper, we use RAINBIO - one of the largest mega-databases of tropical African vascular plant species distributions ever compiled - to address questions about plant and growth form diversity across tropical Africa. RESULTS: The filtered RAINBIO dataset contains 609,776 georeferenced records representing 22,577 species. Growth form data are recorded for 97% of all species. Records are well distributed, but heterogeneous across the continent. Overall, tropical Africa remains poorly sampled. When using sampling units (SU) of 0.5°, just 21 reach appropriate collection density and sampling completeness, and the average number of records per species per SU is only 1.84. Species richness (observed and estimated) and endemism figures per country are provided. Benin, Cameroon, Gabon, Ivory Coast and Liberia appear as the botanically best-explored countries, but none are optimally explored. Forests in the region contain 15,387 vascular plant species, of which 3013 are trees, representing 5-7% of the estimated world's tropical tree flora. The central African forests have the highest endemism rate across Africa, with approximately 30% of species being endemic. CONCLUSIONS: The botanical exploration of tropical Africa is far from complete, underlining the need for intensified inventories and digitization. We propose priority target areas for future sampling efforts, mainly focused on Tanzania, Atlantic Central Africa and West Africa. The observed number of tree species for African forests is smaller than those estimated from global tree data, suggesting that a significant number of species are yet to be discovered. Our data provide a solid basis for a more sustainable management and improved conservation of tropical Africa's unique flora, and is important for achieving Objective 1 of the Global Strategy for Plant Conservation 2011-2020. In turn, RAINBIO provides a solid basis for a more sustainable management and improved conservation of tropical Africa's unique flora.


Assuntos
Biodiversidade , Flores/fisiologia , Clima Tropical , África , Bases de Dados como Assunto , Florestas , Geografia , Especificidade da Espécie , Fatores de Tempo , Árvores/crescimento & desenvolvimento
6.
Appl Plant Sci ; 4(3)2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27011899

RESUMO

PREMISE OF THE STUDY: Microsatellite markers were developed for the species Haumania danckelmaniana (Marantaceae) from central tropical Africa. METHODS AND RESULTS: Microsatellite isolation was performed simultaneously on three different species of Marantaceae through a procedure that combines multiplex microsatellite enrichment and next-generation sequencing. From 80 primers selected for initial screening, 20 markers positively amplified in H. danckelmaniana, of which 10 presented unambiguous amplification products within the expected size range and eight were polymorphic with four to nine alleles per locus. Positive transferability with the related species H. liebrechtsiana was observed for the same 10 markers. CONCLUSIONS: The polymorphic microsatellite markers are suitable for studies in genetic diversity and structure, mating system, and gene flow in H. danckelmaniana and the closely related species H. liebrechtsiana.

7.
PhytoKeys ; (74): 1-18, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28127234

RESUMO

The tropical vegetation of Africa is characterized by high levels of species diversity but is undergoing important shifts in response to ongoing climate change and increasing anthropogenic pressures. Although our knowledge of plant species distribution patterns in the African tropics has been improving over the years, it remains limited. Here we present RAINBIO, a unique comprehensive mega-database of georeferenced records for vascular plants in continental tropical Africa. The geographic focus of the database is the region south of the Sahel and north of Southern Africa, and the majority of data originate from tropical forest regions. RAINBIO is a compilation of 13 datasets either publicly available or personal ones. Numerous in depth data quality checks, automatic and manual via several African flora experts, were undertaken for georeferencing, standardization of taxonomic names and identification and merging of duplicated records. The resulting RAINBIO data allows exploration and extraction of distribution data for 25,356 native tropical African vascular plant species, which represents ca. 89% of all known plant species in the area of interest. Habit information is also provided for 91% of these species.

8.
Front Genet ; 5: 403, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25477901

RESUMO

Vegetation history in tropical Africa is still to date hardly known and the drivers of population differentiation and speciation processes are little documented. It has often been postulated that population fragmentations following climate changes have played a key role in shaping the geographic distribution patterns of genetic diversity and in driving speciation. Here we analyzed phylogeographic patterns (chloroplast-DNA sequences) within and between eight (sister) species of widespread rainforest herbs and lianas from four genera of Marantaceae (Halopegia, Haumania, Marantochloa, Megaphrynium), searching for concordant patterns across species and concordance with the Pleistocene refuge hypothesis. Using 1146 plastid DNA sequences sampled across African tropical lowland rainforest, particularly in the Lower Guinean (LG) phytogeographic region, we analyzed intra- and interspecific patterns of genetic diversity, endemism and distinctiveness. Intraspecific patterns of haplotype diversity were concordant among most species as well as with the species-level diversity pattern of Marantaceae. Highest values were found in the hilly areas of Cameroon and Gabon. However, the spatial distribution of endemic haplotypes, an indicator for refuge areas in general, was not congruent across species. Each proposed refuge exhibited high values of endemism for one or a few species indicating their potential role as area of retraction for the respective species only. Thus, evolutionary histories seem to be diverse across species. In fact, areas of high diversity might have been both refuge and/or crossing zone of recolonization routes i.e., secondary contact zone. We hypothesize that retraction of species into one or the other refuge happened by chance depending on the species' distribution range at the time of climate deterioration. The idiosyncratic patterns found in Marantaceae species are similar to those found among tropical tree species, especially in southern LG.

9.
Cell Microbiol ; 12(6): 765-80, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20070309

RESUMO

Infection of Dictyostelium discoideum with Legionella pneumophila resulted in a large number of differentially regulated genes among them three core autophagy genes, ATG8, ATG9 and ATG16. Macroautophagy contributes to many physiological and pathological processes and might also constitute an important mechanism in cell-autonomous immunity. For further studies we selected the highly conserved ATG9. In colocalization studies with GFP-tagged ATG9 and different organelle marker proteins we neither observed colocalization with mitochondria, the ER nor lysosomes. However, there was partial colocalization with the Golgi apparatus and many ATG9-GFP-containing vesicles localized along microtubules and accumulated around the microtubule organizing centre. ATG9-deficient cells had pleiotropic defects. In addition to growth defects they displayed severe developmental defects, consistent with the known role of autophagy in Dictyostelium development. Unexpectedly, the ATG9 mutant also had a strong phagocytosis defect that was particularly apparent when infecting the cells with L. pneumophila. However, those Legionellae that entered the host could multiply better in mutant than in wild-type cells, because of a less efficient clearance in the early and a more efficient replication in the late phase of infection. We conclude that ATG9 and hence macroautophagy has a protective role during pathogen infection.


Assuntos
Dictyostelium/genética , Legionella pneumophila/crescimento & desenvolvimento , Fagocitose , Proteínas de Protozoários/genética , Dictyostelium/crescimento & desenvolvimento , Dictyostelium/imunologia , Dictyostelium/microbiologia , Técnicas de Inativação de Genes , Complexo de Golgi/química , Microtúbulos/química , Proteínas de Protozoários/análise , Proteínas de Protozoários/fisiologia
10.
Ann Bot ; 104(1): 41-56, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19443460

RESUMO

BACKGROUND AND AIMS: The Marantaceae (550 spp.) is the most derived family in the order Zingiberales and exhibits a complex explosive pollination mechanism. To understand the evolutionary significance of this unique process of pollen transfer, comparative morphological and ecological studies were conducted in Gabon. METHODS: During a total stay of 11 months, 31 species of Marantaceae were investigated at different sites in Gabon. The study included analyses of floral diversity, observations on the pollinator spectrum as well as ecological measurements (e.g. nectar sugar concentration and volume). KEY RESULTS: Analyses reveal five flower types based on flower size and pigmentation, spatial arrangement of the floral tube and presence/absence of nectar guides and conspicuous outer staminodes. Each type is associated with a specific functional pollinator group leading to the description of distinct pollination syndromes. The 'small (horizontal)' flowers are predominantly pollinated by small bees (Thrinchostoma spp., Allodapula ornaticeps), the 'large (horizontal)' and 'medium-sized (horizontal)' flowers by medium-sized bees (Amegilla vivida, Thrinchostoma bicometes), the 'locked (horizontal)' flowers by large bees (Xylocopa nigrita, X. varipes) and the '(large) vertical' flowers by sunbirds. CONCLUSIONS: The longevity of Marantaceae individuals and the omnipresence of their pollinators allowed the specialization to a given functional pollinator group. Intermediate ecological values, however, make occasional pollinator overlaps possible, indicating potential pathways of pollinator shifts. Similar radiation tendencies observed on other continents hint at similar selective pressures and evolutionary constraints.


Assuntos
Flores/anatomia & histologia , Flores/fisiologia , Marantaceae/anatomia & histologia , Marantaceae/fisiologia , Polinização/fisiologia , Animais , Abelhas/fisiologia , Flores/metabolismo , Marantaceae/metabolismo
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