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1.
Scand J Public Health ; 52(3): 379-390, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38346923

RESUMEN

This article presents the design of a seven-country study focusing on childhood vaccines, Addressing Vaccine Hesitancy in Europe (VAX-TRUST), developed during the COVID-19 pandemic. The study consists of (a) situation analysis of vaccine hesitancy (examination of individual, socio-demographic and macro-level factors of vaccine hesitancy and analysis of media coverage on vaccines and vaccination and (b) participant observation and in-depth interviews of healthcare professionals and vaccine-hesitant parents. These analyses were used to design interventions aimed at increasing awareness on the complexity of vaccine hesitancy among healthcare professionals involved in discussing childhood vaccines with parents. We present the selection of countries and regions, the conceptual basis of the study, details of the data collection and the process of designing and evaluating the interventions, as well as the potential impact of the study. Laying out our research design serves as an example of how to translate complex public health issues into social scientific study and methods.


Asunto(s)
COVID-19 , Confianza , Vacilación a la Vacunación , Humanos , Europa (Continente) , Vacilación a la Vacunación/psicología , Vacilación a la Vacunación/estadística & datos numéricos , COVID-19/prevención & control , Padres/psicología , Vacunas contra la COVID-19/administración & dosificación , Niño
2.
Qual Health Res ; 33(13): 1189-1202, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37671951

RESUMEN

While recruitment is an essential aspect of any research project, its challenges are rarely acknowledged. We intend to address this gap by discussing the challenges to the participation of vaccine-hesitant parents defined here as a hard-to-reach, hidden and vulnerable population drawing on extensive empirical qualitative evidence from seven European countries. The difficulties in reaching vaccine-hesitant parents were very much related to issues concerning trust, as there appears to be a growing distrust in experts, which is extended to the work developed by researchers and their funding bodies. These difficulties have been accentuated by the public debate around COVID-19 vaccination, as it seems to have increased parents' hesitancy to participate. Findings from recruiting 167 vaccine-hesitant parents in seven European countries suggest that reflexive and sensible recruitment approaches should be developed.


Asunto(s)
Vacunas contra la COVID-19 , Vacunas , Humanos , Poblaciones Vulnerables , Conocimientos, Actitudes y Práctica en Salud , Aceptación de la Atención de Salud , Padres , Vacunación
3.
Palliat Support Care ; 18(1): 63-68, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31138342

RESUMEN

OBJECTIVE: This paper aims to explore the extent to which the "revivalist" discourse of a good death, which promotes an awareness of dying shapes the lived realities of palliative care patients and their families in Portugal. METHOD: An ethnographic approach was developed. Participant observation was carried out in 2 palliative care units, and this was complemented by in-depth interviews. Ten terminally ill patients, 20 family members, and 20 palliative care professionals were interviewed. RESULTS: The "revivalist" good death script might not be suitable for all dying people, as they might not want an open awareness of dying and, thereby, the acknowledgment of imminent potential death. This might be related to cultural factors and personal circumstances. The "social embeddedness narrative" offers an alternative to the "revivalist" good death script. SIGNIFICANCE OF RESULTS: The "revivalist" discourse, which calls for an open awareness of dying, is not a cultural preference in a palliative care context in Portugal, as it is not in accord with its familial nature.


Asunto(s)
Actitud Frente a la Muerte , Prioridad del Paciente/psicología , Anciano , Antropología Cultural/métodos , Femenino , Humanos , Entrevistas como Asunto/métodos , Masculino , Persona de Mediana Edad , Cuidados Paliativos/métodos , Cuidados Paliativos/psicología , Portugal , Investigación Cualitativa
4.
Nat Prod Rep ; 33(6): 747-50, 2016 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-26892141

RESUMEN

Covering: up to 2016Marine and terrestrial organisms yield a remarkable chemical diversity and are important sources for discovery of new chemical products. In order to maximize the bioprospecting efficiency of natural products (NP), taxonomy, geography and biodiversity are starting to be used to draw conclusions on which taxonomic groups and/or regions may be of interest for future research. However, accurate taxonomic information and sampling location of source organisms have often been overlooked. Although these issues were already reported a few decades ago and improvements have been made, such outstanding problems are still recurrent in recent peer-reviewed literature. Here, we focus on the importance of taxonomic and geographic identification of source material and illustrate how taxonomic and geographic data of source organisms continues to be poorly handled. It is our opinion that this issue needs to be discussed within the NP community with the ultimate goal of improving publication standards and guaranteeing the scientific principle of research reproducibility. Moreover, by doing so, it will be possible to take advantage of information available in the literature to develop cross-disciplinary meta-analyses that may help to advance the state of the art of NP research and future bioprospecting endeavours.


Asunto(s)
Productos Biológicos , Biodiversidad , Productos Biológicos/química , Productos Biológicos/clasificación , Estructura Molecular , Reproducibilidad de los Resultados
5.
J Soc Work End Life Palliat Care ; 12(4): 331-347, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27938027

RESUMEN

The aim of this study was to offer an understanding of the ways in which terminally ill patients may face discrimination due to their visibly altered body. An ethnographic approach was adopted and fieldwork was conducted over 10 months in 2 inpatient hospice units in Portugal. Participant observation was complemented by 50 in-depth interviews with terminally ill patients, family members, and hospice staff. The stigma experienced by terminally ill patients derived mostly from the behavior of peers, extended family members, and friends toward their visibly altered body. There was no evidence that these patients were discredited by their immediate family when they became visibly unwell; unlike what has been reported in previous studies. This finding could be related to the strong familial culture of Portuguese society.


Asunto(s)
Cuidados Paliativos al Final de la Vida , Estigma Social , Enfermo Terminal , Adulto , Anciano , Antropología Cultural , Familia , Salud de la Familia , Femenino , Amigos , Hospitales para Enfermos Terminales , Humanos , Masculino , Persona de Mediana Edad
6.
Death Stud ; 40(5): 290-7, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26765681

RESUMEN

The present study aims to provide insights on the role of in-patient hospices, which are sometimes described as disconnecting spaces. Researchers complement participant observation with in-depth interviews with 10 hospice patients, 20 family members, and 20 members of hospice staff. The findings suggest that the hospice provides a space where patients could enjoy the company of their loved ones without concerns regarding the dying process. The study reveals that the hospice offers a proper alternative to the home setting even in countries characterized by a strong familialistic culture like Portugal.


Asunto(s)
Actitud , Familia , Personal de Salud , Cuidados Paliativos al Final de la Vida , Hospitales para Enfermos Terminales , Pacientes Internos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Portugal , Investigación Cualitativa
7.
J Women Aging ; 28(6): 498-509, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27435363

RESUMEN

There has been a tendency within the literature to ignore how men and women who are very ill and at the end of life perceive and experience their visibly altered bodies. This article aims to provide new insights about this matter. A qualitative research approach was adopted. In-depth interviews were conducted with 10 hospice patients, 20 family members, and 20 members of hospice staff. Findings reveal that because of masculine and feminine norms, physical appearance is more a matter of concern to women than to men who are close to death. This contradicts theories that suggest that patients experience a disinvestment on their sense of masculinity and femininity alongside the process of bodily deterioration and decay prior impending potential death.


Asunto(s)
Imagen Corporal/psicología , Enfermedad Crítica/psicología , Percepción , Apariencia Física , Factores Sexuales , Anciano , Anciano de 80 o más Años , Alopecia/psicología , Actitud del Personal de Salud , Familia/psicología , Femenino , Feminidad , Cuidados Paliativos al Final de la Vida/psicología , Humanos , Masculino , Masculinidad , Investigación Cualitativa , Pérdida de Peso
8.
PLoS Biol ; 10(1): e1001234, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22235194

RESUMEN

Since the first discovery of deep-sea hydrothermal vents along the Galápagos Rift in 1977, numerous vent sites and endemic faunal assemblages have been found along mid-ocean ridges and back-arc basins at low to mid latitudes. These discoveries have suggested the existence of separate biogeographic provinces in the Atlantic and the North West Pacific, the existence of a province including the South West Pacific and Indian Ocean, and a separation of the North East Pacific, North East Pacific Rise, and South East Pacific Rise. The Southern Ocean is known to be a region of high deep-sea species diversity and centre of origin for the global deep-sea fauna. It has also been proposed as a gateway connecting hydrothermal vents in different oceans but is little explored because of extreme conditions. Since 2009 we have explored two segments of the East Scotia Ridge (ESR) in the Southern Ocean using a remotely operated vehicle. In each segment we located deep-sea hydrothermal vents hosting high-temperature black smokers up to 382.8°C and diffuse venting. The chemosynthetic ecosystems hosted by these vents are dominated by a new yeti crab (Kiwa n. sp.), stalked barnacles, limpets, peltospiroid gastropods, anemones, and a predatory sea star. Taxa abundant in vent ecosystems in other oceans, including polychaete worms (Siboglinidae), bathymodiolid mussels, and alvinocaridid shrimps, are absent from the ESR vents. These groups, except the Siboglinidae, possess planktotrophic larvae, rare in Antarctic marine invertebrates, suggesting that the environmental conditions of the Southern Ocean may act as a dispersal filter for vent taxa. Evidence from the distinctive fauna, the unique community structure, and multivariate analyses suggest that the Antarctic vent ecosystems represent a new vent biogeographic province. However, multivariate analyses of species present at the ESR and at other deep-sea hydrothermal vents globally indicate that vent biogeography is more complex than previously recognised.


Asunto(s)
Biodiversidad , Ecosistema , Respiraderos Hidrotermales , Agua de Mar/química , Animales , Regiones Antárticas , Bacterias/clasificación , Bacterias/genética , Bacterias/crecimiento & desarrollo , Crustáceos/clasificación , Crustáceos/genética , Crustáceos/crecimiento & desarrollo , Decápodos/clasificación , Decápodos/genética , Decápodos/crecimiento & desarrollo , Complejo IV de Transporte de Electrones/genética , Gastrópodos/clasificación , Gastrópodos/genética , Gastrópodos/crecimiento & desarrollo , Geografía , Sulfuro de Hidrógeno/metabolismo , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular , Océanos y Mares , Filogenia , ARN Ribosómico 16S/genética , ARN Ribosómico 18S/genética , ARN Ribosómico 28S/genética , Agua de Mar/microbiología , Análisis de Secuencia de ADN , Sodio/metabolismo , Especificidad de la Especie , Temperatura
9.
Soc Sci Med ; 346: 116725, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38432000

RESUMEN

Although Covid-19 was not the first pandemic, it was unique in the scale and intensity with which societies responded. Countries reacted differently to the threat posed by the new virus. The public health crisis affected European societies in many ways. It also influenced the way the media portrayed vaccines and discussed factors related to vaccine hesitancy. Europeans differed in their risk perceptions, attitudes towards vaccines and vaccine uptake. In European countries, Covid-19-related discourses were at the centre of media attention for many months. This paper reports on a media analysis which revealed significant differences as well as some similarities in the media debates in different countries. The study focused on seven European countries and considered two dimensions of comparison: between the pre-Covid period and the beginning of the Covid pandemic period, and between countries. The rich methodological approach, including linguistics, semantic field analysis and discourse analysis of mainstream news media, allowed the authors to explore the set of meanings related to vaccination that might influence actors' agency. This approach led the authors to redefine vaccine hesitancy in terms of characteristics of the "society in the situation" rather than the psychological profile of individuals. We argue that vaccine hesitancy can be understood in terms of agency and temporality. This dilemma of choice that transforms the present into an irreversible past and must be taken in relation to an uncertain future, is particularly acute under the pressure of urgency and when someone's health is at stake. As such, it is linked to how vaccine meaning is co-produced within public discourses.


Asunto(s)
COVID-19 , Medios de Comunicación Sociales , Vacunas , Humanos , Incertidumbre , Vacunación , Vacunas/uso terapéutico , COVID-19/epidemiología , COVID-19/prevención & control , Europa (Continente)/epidemiología
10.
Public Health Pract (Oxf) ; 6: 100438, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37885614

RESUMEN

Objectives: The concept of vaccine hesitancy encompasses multiple views on the subject. However, there has been an increasing polarization of the discourse on vaccine hesitancy leading to the stigmatization of those parents who expressed doubts or concerns regarding vaccination practices. The present study aimed to explore the drivers and consequences of polarized discourses on vaccination in the Portuguese context. This paper is part of a broader study which aims to gain a deeper understanding about the phenomenon of vaccine hesitancy at the European level. Study design: A qualitative research design was used. Methods: The sample was comprised of thirty-one Portuguese vaccine hesitant parents who were interviewed. A thematic analysis of the transcribed interviews was performed which allowed us to identify key themes. Results: The results showed that the labelling of vaccine-hesitant parents as 'anti-vaxxers' along with social media play a crucial role in promoting the polarization of vaccine-related attitudes. The stigmatization of vaccine hesitant parents has a disruptive impact on their social network leading them to search for online platforms where they can exchange vaccines-related information without being discriminated. Conclusions: The stigma and discrimination experienced by vaccine-hesitant parents stimulated that hesitancy becomes more entrenched. Therefore, pluralism should be used to tailor vaccination promotion campaigns to different targets, promoting its reach and efficacy.

12.
Front Microbiol ; 14: 1158441, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37065153

RESUMEN

The deep-sea covers over 70% of the Earth's surface and harbors predominantly uncharacterized bacterial communities. Actinobacteria are the major prokaryotic source of bioactive natural products that find their way into drug discovery programs, and the deep-sea is a promising source of biotechnologically relevant actinobacteria. Previous studies on actinobacteria in deep-sea sediments were either regionally restricted or did not combine a community characterization with the analysis of their bioactive potential. Here we characterized the actinobacterial communities of upper layers of deep-sea sediments from the Arctic and the Atlantic (Azores and Madeira) ocean basins, employing 16S rRNA metabarcoding, and studied the biosynthetic potential of cultivable actinobacteria retrieved from those samples. Metabarcoding analysis showed that the actinobacterial composition varied between the sampled regions, with higher abundance in the Arctic samples but higher diversity in the Atlantic ones. Twenty actinobacterial genera were detected using metabarcoding, as a culture-independent method, while culture-dependent methods only allowed the identification of nine genera. Isolation of actinobacteria resulted on the retrieval of 44 isolates, mainly associated with Brachybacterium, Microbacterium, and Brevibacterium genera. Some of these isolates were only identified on a specific sampled region. Chemical extracts of the actinobacterial isolates were subsequently screened for their antimicrobial, anticancer and anti-inflammatory activities. Extracts from two Streptomyces strains demonstrated activity against Candida albicans. Additionally, eight extracts (obtained from Brachybacterium, Brevibacterium, Microbacterium, Rhodococcus, and Streptomyces isolates) showed significant activity against at least one of the tested cancer cell lines (HepG2 and T-47D). Furthermore, 15 actinobacterial extracts showed anti-inflammatory potential in the RAW 264.4 cell model assay, with no concomitant cytotoxic response. Dereplication and molecular networking analysis of the bioactive actinobacterial extracts showed the presence of some metabolites associated with known natural products, but one of the analyzed clusters did not show any match with the natural products described as responsible for these bioactivities. Overall, we were able to recover taxonomically diverse actinobacteria with different bioactivities from the studied deep-sea samples. The conjugation of culture-dependent and -independent methods allows a better understanding of the actinobacterial diversity of deep-sea environments, which is important for the optimization of approaches to obtain novel chemically-rich isolates.

13.
Front Microbiol ; 13: 828469, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35432234

RESUMEN

Deep coral-dominated communities play paramount roles in benthic environments by increasing their complexity and biodiversity. Coral-associated microbes are crucial to maintain fitness and homeostasis at the holobiont level. However, deep-sea coral biology and their associated microbiomes remain largely understudied, and less from remote and abyssal environments such as those in the Clarion-Clipperton Fracture Zone (CCZ) in the tropical Northeast (NE) Pacific Ocean. Here, we study microbial-associated communities of abyssal gorgonian corals and anemones (>4,000 m depth) in the CCZ; an area harboring the largest known global reserve of polymetallic nodules that are commercially interesting for the deep-sea nodule mining. Coral samples (n = 25) belonged to Isididae and Primnoidae families, while anemones (n = 4) to Actinostolidae family. Significant differences in bacterial community compositions were obtained between these three families, despite sharing similar habitats. Anemones harbored bacterial microbiomes composed mainly of Hyphomicrobiaceae, Parvibaculales, and Pelagibius members. Core microbiomes of corals were mainly dominated by different Spongiibacteraceae and Terasakiellaceae bacterial members, depending on corals' taxonomy. Moreover, the predicted functional profiling suggests that deep-sea corals harbor bacterial communities that allow obtaining additional energy due to the scarce availability of nutrients. This study presents the first report of microbiomes associated with abyssal gorgonians and anemones and will serve as baseline data and crucial insights to evaluate and provide guidance on the impacts of deep-sea mining on these key abyssal communities.

14.
R Soc Open Sci ; 9(10): 220885, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36249326

RESUMEN

Deep-sea hydrothermal vents host lush chemosynthetic communities, dominated by endemic fauna that cannot live in other ecosystems. Despite over 500 active vents found worldwide, the Arctic has remained a little-studied piece of vent biogeography. Though located as early as 2001, the faunal communities of the Aurora Vent Field on the ultra-slow spreading Gakkel Ridge remained unsampled until recently, owing to difficulties with sampling on complex topography below permanent ice. Here, we report an unusual cocculinid limpet abundant on inactive chimneys in Aurora (3883-3884 m depth), describing it as Cocculina aurora n. sp. using an integrative approach combining traditional dissection, electron microscopy, molecular phylogeny, and three-dimensional anatomical reconstruction. Gross anatomy of the new species was typical for Cocculina, but it has a unique radula with broad, multi-cuspid rachidian where the outermost lateral is reduced compared to typical cocculinids. A phylogenetic reconstruction using the mitochondrial COI gene also confirmed its placement in Cocculina. Only the second cocculinid found at vents following the description of the Antarctic Cocculina enigmadonta, this is currently the sole cocculinid restricted to vents. Our discovery adds to the evidence that Arctic vents host animal communities closely associated with wood falls and distinct from other parts of the world.

15.
Antonie Van Leeuwenhoek ; 100(1): 83-98, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21359663

RESUMEN

Frenulates are a group of gutless marine annelids belonging to the Siboglinidae that are nutritionally dependent upon endosymbiotic bacteria. We have characterized the bacteria associated with several frenulate species from mud volcanoes in the Gulf of Cadiz by PCR-DGGE of bacterial 16S rRNA genes, coupled with analysis of 16S rRNA gene libraries. In addition to the primary symbiont, bacterial consortia (microflora) were found in all species analysed. Phylogenetic analyses indicate that the primary symbiont in most cases belongs to the Gammaproteobacteria and were related to thiotrophic and methanotrophic symbionts from other marine invertebrates, whereas members of the microflora were related to multiple bacterial phyla. This is the first molecular evidence of methanotrophic bacteria in at least one frenulate species. In addition, the occurrence of the same bacterial phylotype in different Frenulata species, from different depths and mud volcanoes suggests that there is no selection for specific symbionts and corroborates environmental acquisition as previously proposed for this group of siboglinids.


Asunto(s)
Bacterias/aislamiento & purificación , Biodiversidad , Sedimentos Geológicos/microbiología , Poliquetos/microbiología , Agua de Mar/microbiología , Animales , Océano Atlántico , Bacterias/clasificación , Bacterias/genética , Fenómenos Fisiológicos Bacterianos , Datos de Secuencia Molecular , Filogenia , Poliquetos/fisiología , Simbiosis
16.
Health Soc Care Community ; 29(6): e232-e239, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-33704855

RESUMEN

Little has been said about the disruptive impact that the inability to eat and to participate in mealtimes has for patients with a life-threatening illness and their families. The aim of the current study is to overcome this gap and shed light on how food and eating practices are experienced by families at the end-of-life. An ethnographic research was developed in two Portuguese palliative care units: participant observation was conducted during 10 months and in-depth interviews were carried out with 10 patients with a life-threatening illness, 20 family members and 20 palliative care professionals. Food is not only a matter of nutrition in a biological sense, but also an act of giving care to patients with a life-threatening illness. The findings suggest that food and eating practices affect the processes of relationality and of doing family at the end-of-life in Portugal. Attention is particularly paid to gender differences. The study supports recent sociological research which understands the dying process as a relational experience and intends to develop sociological knowledge on the materialities of care.


Asunto(s)
Antropología Cultural , Familia , Muerte , Humanos , Cuidados Paliativos , Portugal
17.
Health (London) ; 21(5): 555-572, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28805149

RESUMEN

This article aims to provide insights into the ways in which trans people (i.e. those whose gender identity or expression do not align with their assigned sex at birth) in Portugal make sense of the diagnosis of gender dysphoria. Drawing upon in-depth interviews with 10 trans men and 9 trans women carried out by the TRANSRIGHTS team, we identified three major themes: (a) contestation of gender dysphoria as a (mental) illness, (b) instrumental resistance to complete demedicalisation of gender dysphoria and (c) strategic conformation to gender essentialism within the diagnostic process of gender dysphoria. We found that the need to access medical treatments leads some trans people to approach the diagnosis strategically. While almost all trans people were in favour of the depathologisation of gender dysphoria and at the same time were against its demedicalisation, mainly for instrumental reasons, a few demonstrated contrasting positions whether by agreeing with the idea of gender dysphoria as a pathology or by rejecting medicalisation. The study offers a more nuanced perspective on gender dysphoria than that described in previous sociological and transgender literature.


Asunto(s)
Disforia de Género/diagnóstico , Personas Transgénero/psicología , Femenino , Identidad de Género , Humanos , Entrevistas como Asunto , Masculino , Portugal
18.
Sci Rep ; 6: 26808, 2016 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-27245847

RESUMEN

Polymetallic nodule mining at abyssal depths in the Clarion Clipperton Fracture Zone (Eastern Central Pacific) will impact one of the most remote and least known environments on Earth. Since vast areas are being targeted by concession holders for future mining, large-scale effects of these activities are expected. Hence, insight into the fauna associated with nodules is crucial to support effective environmental management. In this study video surveys were used to compare the epifauna from sites with contrasting nodule coverage in four license areas. Results showed that epifaunal densities are more than two times higher at dense nodule coverage (>25 versus ≤10 individuals per 100 m(2)), and that taxa such as alcyonacean and antipatharian corals are virtually absent from nodule-free areas. Furthermore, surveys conducted along tracks from trawling or experimental mining simulations up to 37 years old, suggest that the removal of epifauna is almost complete and that its full recovery is slow. By highlighting the importance of nodules for the epifaunal biodiversity of this abyssal area, we urge for cautious consideration of the criteria for determining future preservation zones.


Asunto(s)
Organismos Acuáticos/fisiología , Conservación de los Recursos Naturales , Sedimentos Geológicos/análisis , Invertebrados/fisiología , Metales Pesados , Minería , Animales , Biodiversidad , Ecosistema , Metales Pesados/análisis , Océano Pacífico , Densidad de Población , Dinámica Poblacional , Grabación en Video
20.
Biol Bull ; 208(1): 20-8, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15713809

RESUMEN

Vestimentiferan tubeworms are ecologically important members of deep-sea chemosynthetic communities, including hydrothermal vents and cold seeps. Some are community dominants and others are primary colonists of new vent sites; they include some of the longest living and fastest growing marine invertebrates. Their mechanisms of propagation, dispersal, and genetic exchange have been widely discussed. Direct sperm transfer from males to females has been documented in one species, Ridgeia piscesae, but others are known to discharge what are apparently primary oocytes. Brooding of embryos has never been observed in any vestimentiferan. These observations have led to the supposition that fertilization might be external in most species. Here we report sperm storage at the posterior end of the oviduct in five species, including tubeworms from both vents and seeps. We show experimentally that most eggs are inseminated internally, that fertilization rate is typically lower than 100%, that meiosis is completed after eggs are released from the female, and that the dispersal phase includes the entire embryonic period.


Asunto(s)
Poliquetos/fisiología , Espermatozoides/fisiología , Animales , Femenino , Histocitoquímica , Masculino , Microscopía Electrónica de Transmisión , Oocitos/fisiología , Poliquetos/anatomía & histología , Poliquetos/ultraestructura , Reproducción/fisiología
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