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1.
Plants (Basel) ; 12(19)2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37836194

RESUMO

The Revillagigedo Archipelago, located in the Eastern Pacific Ocean, stands out for its unique biological richness and endemism. These islands remained uninhabited until the second half of the twentieth century, allowing a better conservation status than on other oceanic islands. However, the continuous introduction of potentially invasive alien plant species, and the lack of adequate control or eradication actions, jeopardize the conservation and restoration of these islands' fragile ecosystems. We present the most complete vascular plant species inventory and an updated list of alien plant species of the Revillagigedo Archipelago, which was compiled through an extensive review of national and international plant collections and other sources. Our 272 species list includes 106 alien plant species (39.3%; 104 in Socorro, and 16 in Clarion): 67 (24.8%) are naturalized, 14 (5.2%) are casual aliens, and 25 (9.3%) subsist under cultivation. The documented alien species belong to 73 families. Annual and perennial herbs are the prevailing life forms in the alien flora, while naturalized species are primarily native to North America. The number of introduced species has increased significantly since the islands became inhabited. Many of the recently introduced species pose a major invasion risk like on other islands of the world.

2.
Rev Cient Odontol (Lima) ; 10(4): e134, 2023.
Artigo em Espanhol | MEDLINE | ID: mdl-38390610

RESUMO

Peri-implantitis (PI) is the inflammatory reaction of the peri-implant mucosa, accompanied by the progressive loss of supporting bone around the implant, which can compromise its stability, function and aesthetics. It is diagnosed by radiographic measurement of the alveolar bone level, with or without clinical symptoms of inflammation and a probing depth greater than 4 mm. The objective of this work was to review the scientific evidence on the prevalence, etiology, predisposing factors, clinical behavior and imaging characteristics of PI. An electronic search was carried out in Google Scholar, PubMed and Scielo, considering the period between 2010-2022, and a total of 40 articles were selected. It is concluded that the main etiological agent of PI is the biofilm, however, its appearance and severity may be associated with the presence of predisposing factors such as Diabetes Mellitus, smoking, pre-existing periodontal disease and absence of keratinized mucosa, among others. Clinically, PI is related to bleeding on probing, gingival recession, and suppuration. Imaging evaluation of the peri-implant defect is routinely performed with periapical radiographs; Recent use of cone-beam computed tomography has allowed three-dimensional assessment of the defect, although considerations of radiation dose to the patient and image artifacts have been made that may limit its extensive use.

3.
Mol Phylogenet Evol ; 173: 107496, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35569809

RESUMO

The Panamic Clingfish Gobiesox adustus is widely distributed in the Tropical Eastern Pacific (TEP), from the central Gulf of California, Mexico to Ecuador, including the oceanic Revillagigedo Archipelago, and Isla del Coco. This cryptobenthic species is restricted to very shallow rocky-reef habitats. Here, we used one mitochondrial and three nuclear DNA markers from 155 individuals collected across the distribution range of the species in order to evaluate if geographically structured populations exist and to elucidate its evolutionary history. Phylogenetic analyses recovered a monophyletic group, with four well-supported, allopatric subgroups. Each subgroup corresponded to one of the following well-known biogeographic regions/provinces: 1) the Revillagigedo Archipelago, 2) the Cortez + Mexican provinces (Mexico), 3) the Panamic province (from El Salvador to Ecuador), and 4) Isla del Coco. A molecular-clock analysis showed a mean date for the divergence between clade I (the Revillagigedos and Cortez + Mexican provinces) and clade II (Panamic province and Isla del Coco) in the Pliocene, at ca. 5.33 Mya. Within clade I, the segregation between the Revillagigedos and Cortez + Mexican province populations was dated at ca. 1.18 Mya, during the Pleistocene. Within clade II, the segregation between samples of Isla del Coco and the Panamic province samples was dated at ca. 0.77 Mya, during the Pleistocene. The species tree, Bayesian species delimitation tests (BPP and STACEY), the ΦST, AMOVA, and the substantial genetic distances that exist between those four subgroups, indicate that they are independent evolutionary units. These cladogenetic events seem to be related to habitat discontinuities, and oceanographic and geological processes that produce barriers to gene flow for G. adustus, effects of which are enhanced by the intrinsic ecological characteristics of this species.


Assuntos
Evolução Biológica , Peixes , Animais , Teorema de Bayes , DNA Mitocondrial/genética , Peixes/genética , Humanos , Filogenia , Filogeografia
4.
Mol Ecol ; 28(20): 4535-4548, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31332852

RESUMO

Genetic structure can be influenced by local adaptation to environmental heterogeneity and biogeographic barriers, resulting in discrete population clusters. Geographic distance among populations, however, can result in continuous clines of genetic divergence that appear as structured populations. Here, we evaluate the relevant importance of these three factors over a landscape characterized by environmental heterogeneity and the presence of a hypothesized biogeographic barrier in producing population genetic structure within 13 codistributed snake species using a genomic data set. We demonstrate that geographic distance and environmental heterogeneity across western North America contribute to population genomic divergence. Surprisingly, landscape features long thought to contribute to biogeographic barriers play little role in divergence community wide. Our results suggest that isolation by environment is the most important contributor to genomic divergence. Furthermore, we show that models of population clustering that incorporate spatial information consistently outperform nonspatial models, demonstrating the importance of considering geographic distances in population clustering. We argue that environmental and geographic distances as drivers of community-wide divergence should be explored before assuming the role of biogeographic barriers.


Assuntos
Evolução Molecular , Fenômenos Genéticos/fisiologia , Especiação Genética , Isolamento Reprodutivo , Serpentes/classificação , Animais , Evolução Biológica , Genoma/genética , Geografia , Filogenia , Filogeografia , Dinâmica Populacional , Serpentes/genética
5.
J Environ Manage ; 203(Pt 3): 962-972, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28728971

RESUMO

The selection of the working fluid for Organic Rankine Cycles has traditionally been addressed from systematic heuristic methods, which perform a characterization and prior selection considering mainly one objective, thus avoiding a selection considering simultaneously the objectives related to sustainability and safety. The objective of this work is to propose a methodology for the optimal selection of the working fluid for Organic Rankine Cycles. The model is presented as a multi-objective approach, which simultaneously considers the economic, environmental and safety aspects. The economic objective function considers the profit obtained by selling the energy produced. Safety was evaluated in terms of individual risk for each of the components of the Organic Rankine Cycles and it was formulated as a function of the operating conditions and hazardous properties of each working fluid. The environmental function is based on carbon dioxide emissions, considering carbon dioxide mitigation, emission due to the use of cooling water as well emissions due material release. The methodology was applied to the case of geothermal facilities to select the optimal working fluid although it can be extended to waste heat recovery. The results show that the hydrocarbons represent better solutions, thus among a list of 24 working fluids, toluene is selected as the best fluid.


Assuntos
Dióxido de Carbono/química , Energia Geotérmica/economia , Meio Ambiente
6.
PLoS One ; 9(5): e97682, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24837300

RESUMO

Vertebrates are currently going extinct at an alarming rate, largely because of habitat loss, global warming, infectious diseases, and human introductions. Island ecosystems are particularly vulnerable to invasive species and other ecological disturbances. Properly documenting historic and current species distributions is critical for quantifying extinction events. Museum specimens, field notes, and other archived materials from historical expeditions are essential for documenting recent changes in biodiversity. The Islas Revillagigedo are a remote group of four islands, 700-1100 km off the western coast of mainland México. The islands are home to many endemic plants and animals recognized at the specific- and subspecific-levels, several of which are currently threatened or have already gone extinct. Here, we recount the initial discovery of an endemic snake Hypsiglena ochrorhyncha unaocularus Tanner on Isla Clarión, the later dismissal of its existence, its absence from decades of field surveys, our recent rediscovery, and recognition of it as a distinct species. We collected two novel complete mitochondrial (mt) DNA genomes and up to 2800 base-pairs of mtDNA from several other individuals, aligned these with previously published mt-genome data from samples throughout the range of Hypsiglena, and conducted phylogenetic analyses to infer the biogeographic origin and taxonomic status of this population. We found the Isla Clarión population to be most closely related to populations in the Sonora-Sinaloa state border area of mainland México and Isla Santa Catalina, in the Gulf of California. Based on genetics, morphology, and geographic distributions, we also recognize these two other lineages as distinct species. Our study shows the importance of museum specimens, field notes, and careful surveys to accurately document biodiversity and brings these island endemics (Clarión and Santa Catalina nightsnakes) and mainland population near the Sonora-Sinaloa state border to the attention of conservation biologists currently monitoring biodiversity in these fragile subtropical ecosystems.


Assuntos
Serpentes/classificação , Serpentes/genética , Animais , Biodiversidade , California , DNA Mitocondrial , Genoma Mitocondrial , Ilhas , México , Oceano Pacífico , Filogenia
7.
J Parasitol ; 99(2): 270-6, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23043349

RESUMO

The Socorro dove Zenaida graysoni , endemic to Socorro Island, was last reported in the wild in 1972. Fortunately, the species has been propagated in zoos in Europe and the United States, and plans are under way to re-introduce it to its native habitat. This will be the first known attempt to return a bird species extinct in the wild to its ancestral island. In order to assess the disease threats the Socorro dove may face, the avifauna of Socorro Island, with a specific focus on Socorro ground doves Columbina passerina socorroensis and mourning doves Zenaida macroura , as well as Socorro doves in captivity, were screened for blood parasites of the genera Plasmodium , Haemoproteus, Leucocytozoon, and Trypanosoma spp. We found Haemoproteus spp. in 17 (74%) of 23 Socorro ground doves, 23 (92%) of 25 mourning doves, and 3 (14%) of 21 northern mockingbirds; none of the other bird species showed infections. Here, we report the phylogenetic analysis of 19 distinct lineages of Haemoproteus spp. detected in birds of Socorro Island and compare their evolutionary relationships to parasites detected in the avifauna of the Galápagos Islands, continental Latin America, and Europe. Microscopic examination revealed 1 mourning dove infected with Plasmodium ( Haemamoeba ), thus underscoring the importance of using both PCR and microscopy when analyzing avian blood samples for hemosporidian parasites. The study confirms that the Socorro dove will most likely be exposed to Haemoproteus spp. that currently infect mourning doves and Socorro ground doves of Socorro Island. A monitoring program for both birds and vectors should be implemented to establish the prevalence of Plasmodium sp. and as a necessary conservation measure for critically endangered birds on the island.


Assuntos
Biodiversidade , Doenças das Aves/parasitologia , Columbidae/parasitologia , Haemosporida/classificação , Filogenia , Infecções Protozoárias em Animais/parasitologia , Animais , Animais de Zoológico , Doenças das Aves/epidemiologia , Aves , Extinção Biológica , Haemosporida/genética , Ilhas/epidemiologia , México/epidemiologia , Reação em Cadeia da Polimerase/veterinária , Prevalência , Infecções Protozoárias em Animais/epidemiologia
8.
J Parasitol ; 99(3): 513-21, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23240808

RESUMO

Here we describe Haemoproteus (Haemoproteus) multivolutinus n. sp. from a tambourine dove (Turtur timpanistria) of Uganda and Haemoproteus (Haemoproteus) paramultipigmentatus n. sp. (Haemosporida, Haemoproteidae) from the Socorro common ground dove (Columbina passerina socorroensis) of Socorro Island, Mexico. These parasites are described based on the morphology of their blood stages and segments of the mitochondrial cytochrome b gene that can be used for molecular identification and diagnosis of these species. Gametocytes of H. multivolutinus possess rod-like pigment granules and are evenly packed with volutin, which masks pigment granules and darkly stains both macro- and microgametocytes in the early stages of their development. Based on these 2 characters, H. multivolutinus can be readily distinguished from other species of hemoproteids parasitizing columbiform (Columbiformes) birds. Haemoproteus paramultipigmentatus resembles Haemoproteus multipigmentatus; it can be distinguished from the latter parasite primarily due to the broadly ovoid shape of its young gametocytes and significantly fewer pigment granules in its fully developed gametocytes. We provide illustrations of blood stages of the new species, and phylogenetic analyses identify DNA lineages closely related to these parasites. Cytochrome b lineages of Haemoproteus multivolutinus and H. paramultipigmentatus cluster with hippoboscid-transmitted lineages of hemoproteids; thus these parasites likely belong to the subgenus Haemoproteus. We emphasize the importance of using cytochrome b sequences in conjunction with thorough microscopic descriptions to facilitate future identification of these and other avian hemosporidian species.


Assuntos
Doenças das Aves/parasitologia , Columbidae/parasitologia , Haemosporida/classificação , Infecções Protozoárias em Animais/parasitologia , Animais , Doenças das Aves/sangue , Doenças das Aves/epidemiologia , Citocromos b/genética , Eritrócitos/parasitologia , Haemosporida/genética , Haemosporida/ultraestrutura , México/epidemiologia , Dados de Sequência Molecular , Filogenia , Prevalência , Infecções Protozoárias em Animais/sangue , Infecções Protozoárias em Animais/epidemiologia , Uganda/epidemiologia
9.
Health Econ Rev ; 2(1): 16, 2012 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-22943676

RESUMO

BACKGROUND: The lower sales price of generic lamivudine has caused healthcare administrators to consider abolishing fixed-dose antiretroviral combinations (FDCs) that contain lamivudine and emtricitabine. The alternative is to administer the individual components of the FDCs separately, thus incorporating the new generic lamivudine medication. METHODS: The Balearic Islands Health Service ordered the discontinuation of the treatment with FDCs in July 2010, but FDCs were reintroduced in August 2010. At that point, an independent, retrospective cost analysis was performed by Son Llàtzer Hospital. A total of 75 patients who were treated from July to August 2010 underwent replacement of their FDC treatment with the individual components. Additionally, 150 patients who continued using FDCs were randomly selected. For both patient groups, the antiretroviral therapy that was administered and the costs associated with management of adverse events were recorded. The study period used for the cost calculations was the average number of days that patients used separate components of FDCs (120 days). An alternative analysis was performed to consider the costs of the extra follow-up visit (consultation and clinical tests) that was required for patients who changed their antiretroviral therapy. RESULTS: Considering antiretroviral therapies and adverse events, the administration of the separate components increased the total daily cost by 0.72 € per patient compared to treatment with FDCs. When the cost of an extra follow-up visit was considered, the daily cost increased by 3.61 € per patient. CONCLUSIONS: Our study suggests that the discontinuation of FDC treatment and the replacement with the administration of separate antiretroviral agents could lead to an increase in healthcare costs due to the higher rate of adverse events that was observed with the discontinuation of FDCs.

10.
Acta odontol. venez ; 50(4)2012. ilus
Artigo em Espanhol | LILACS | ID: lil-678984

RESUMO

La radiología representa un área muy importante dentro del campo médico y odontológico, siendo básica y esencial para el diagnóstico y, por lo tanto, para la terapéutica. En endodoncia, la toma de radiografías es imprescindible durante las diferentes etapas del tratamiento, para poder culminar con éxito la terapia endodóntica, por lo que es fundamental la obtención de radiografías de alta calidad diagnóstica. En determinadas situaciones, aún cuando la técnica de toma de la radiografía y su proceso de revelado hayan permitido la obtención de radiografías con imágenes adecuadas, las mismas no son útiles para el propósito que se requieren, como puede ser la localización de un objeto extraño, la ubicación de una estructura anatómica que imposibilita la visión directa a una pieza dentaria o de un conducto radicular en específico, por lo que el odontólogo debe manejar las diferentes técnicas de localización radiográfica y su interpretación. En la presente revisión se destaca la importancia de las técnicas de localización radiográfica, su definición, indicaciones y técnicas de localización aplicadas al área de endodoncia, los aspectos básicos para su realización y como se interpretan las imágenes obtenidas


The Radiology represents an important area in the medical and dentist field, it's basic and essential for the diagnostic and therapeutic. The endodontic treatment demands the use of radiographies during it's different stages, this radiographies must be of the must high quality to finish successfully the dentist therapy. In certain occasions, the radiographies don't attain to get the result for it has been used, even when the Dentist had used the correctly radiographic technology and correct radiographic film processing, because it doesn't easy show the location of rare objects, anatomic structures, tooth or root canals. The present review make emphasize in the importance of location radiographic technics, it's indications, definitions and locations technics applied to the endodontic treatment, it's basics aspects of carrying out and how to interpret the x-ray image


Assuntos
Humanos , Masculino , Feminino , Métodos , Radiografia Dentária , Métodos
11.
J Vector Ecol ; 36(1): 213-20, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21635660

RESUMO

Avian malaria (Plasmodium spp.) has been implicated in the decline of avian populations in the Hawaiian Islands and it is generally agreed that geographically isolated and immunologically naïve bird populations are particularly vulnerable to the pathogenic effects of invasive malaria parasites. In order to assess the potential disease risk of malaria to the avifauna of Socorro Island, México, we surveyed for Plasmodium isolates from 1,300 resident field-caught mosquitoes. Most of them were identified as Aedes (Ochlerotatus) taeniorhynchus (Wiedemann, 1821), which were abundant in the salt marshes. We also collected Culex quinquefasciatus Say, 1823 close to human dwellings. Mitochondrial ND5 and COII gene sequences of Ae. taeniorhynchus were analyzed and compared to corresponding sequences of mosquitoes of the Galápagos Islands, Latin America, and the North American mainland. Aedes lineages from Socorro Island clustered most closely with a lineage from the continental U.S. Plasmodium spp. DNA was isolated from both species of mosquitoes. From 38 positive pools, we isolated 11 distinct mitochondrial Cytb lineages of Plasmodium spp. Seven of the Plasmodium lineages represent previously documented avian infective strains while four were new lineages. Our results confirm a potential risk for the spread of avian malaria and underscore the need to monitor both the mosquito and avian populations as a necessary conservation measure to protect endangered bird species on Socorro Island.


Assuntos
Aedes/classificação , Aedes/parasitologia , Culex/classificação , Culex/parasitologia , Malária Aviária/transmissão , Plasmodium/patogenicidade , Aedes/genética , Animais , Culex/genética , Geografia , Malária Aviária/parasitologia , México , Filogenia , Reação em Cadeia da Polimerase
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