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1.
Am J Bot ; 101(4): 587-97, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24688055

RESUMO

PREMISE OF THE STUDY: The term colleter is applied to trichomes or emergences positioned close to developing vegetative and floral meristems that secrete a sticky, mucilaginous, and/or lipophilic exudate. Several ecological functions are attributed to these glands, but none are exclusive to colleters. Patterns of morphology and distribution of colleters may be valuable for systematics and phylogeny, especially concerning problematic and large groups such as the subtribe Pleurothallidinae, and are also essential to understand the evolution of these glands in Orchidaceae as a whole. METHODS: We used scanning electron and light microscopy to examine the structure and occurrence of trichomes on bracts and sepals and in the invaginations of the external ovary wall (IEOW) in flowers in several developmental stages from species in seven genera. KEY RESULTS: The exudate was composed of polysaccharides, lipophilic, and phenolic compounds. Colleters were secretory only during the development of floral organs, except for the glands in the IEOW that were also active in flowers at anthesis. After the secretory phase, fungal hyphae were found penetrating senescent trichomes. CONCLUSIONS: Trichome-like colleters seem to be a widespread character in Epidendroideae, and digitiform colleters are possibly the common type in this subfamily. Mucilage from IEOW colleters may aid in the establishment of symbiotic fungi necessary for seed germination. The presence of colleters in the IEOW may be a case of homeoheterotopy, in which extrafloral nectaries that produce simple sugar-based secretions (as in other orchid species) have changed to glands that produce secretions with complex polysaccharides, as in Pleurothallidinae.


Assuntos
Flores/anatomia & histologia , Flores/fisiologia , Orchidaceae/anatomia & histologia , Orchidaceae/fisiologia , Flores/crescimento & desenvolvimento , Flores/ultraestrutura , Meristema/anatomia & histologia , Meristema/crescimento & desenvolvimento , Meristema/fisiologia , Meristema/ultraestrutura , Microscopia Eletrônica de Varredura , Orchidaceae/crescimento & desenvolvimento , Orchidaceae/ultraestrutura , Mucilagem Vegetal/metabolismo
2.
Conserv Biol ; 26(2): 315-23, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22260376

RESUMO

Despite its necessity, integration of natural and social sciences to inform conservation efforts has been difficult. We examined the views of 63 scientists and practitioners involved in marine management in Mexico's Gulf of California, the central California coast, and the western Pacific on the challenges associated with integrating social science into research efforts that support ecosystem-based management (EBM) in marine systems. We used a semistructured interview format. Questions focused on how EBM was developed for these sites and how contextual factors affected its development and outcomes. Many of the traditional challenges linked with interdisciplinary research were present in the EBM projects we studied. However, a number of contextual elements affected how mandates to include social science were interpreted and implemented as well as how easily challenges could be addressed. For example, a common challenge is that conservation organizations are often dominated by natural scientists, but for some projects it was easier to address this imbalance than for others. We also found that the management and institutional histories that came before EBM in specific cases were important features of local context. Because challenges differed among cases, we believe resolving challenges to interdisciplinary research should be context specific.


Assuntos
Ecossistema , Animais , California , Conservação dos Recursos Naturais , Biologia Marinha , México , Oceano Pacífico
3.
PLoS One ; 16(4): e0249725, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33857188

RESUMO

While there is substantial literature about the socio-cultural characteristics and values associated with recreational and commercial fisheries in the U.S., studies directed at those who 'fish for food'-those who depend on consuming their catch to various degrees-are relatively sparse. Using qualitative data collected through 80 semi-structured interviews with fishers in the summer and fall of 2018 in Carteret County, North Carolina, this study aims to better understand the group of recreational fishers who consume their catch by describing social and cultural dimensions and values associated with fishing for food, examining the role of infrastructure in facilitating access to benefits associated with this activity, and considering how knowledge of existing licensing regulations surrounding subsistence license waivers affect this fishing community. Interviews conducted at free public fishing structures in the region revealed that fishers derive a variety of values and benefits from fishing at these sites, including access to recreation, nutrition, a social community, and mental health benefits, which were found to be negatively impacted by Hurricane Florence in September 2018. We also found an informal economy of sharing catch on- and off-site that extends the reach and benefits facilitated by public infrastructure to people beyond those using it directly. Overall, we call for conceptualizations of 'fishing for food' that include aspects that go beyond traditional definitions of 'subsistence' or 'recreational' fishing such as food security, access, and less obvious social and cultural motivations behind the activity. These findings are a compelling rationalization for the creation and maintenance of formal and informal fishing places locally and, by extension, in other coastal areas, given the array of benefits provided by access to these types of locations.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Pesqueiros/estatística & dados numéricos , Abastecimento de Alimentos/estatística & dados numéricos , Alimentos Marinhos/provisão & distribuição , Adolescente , Adulto , Animais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , North Carolina , Recreação , Inquéritos e Questionários , Adulto Jovem
4.
Ambio ; 50(5): 981-989, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33454882

RESUMO

The international development community is off-track from meeting targets for alleviating global malnutrition. Meanwhile, there is growing consensus across scientific disciplines that fish plays a crucial role in food and nutrition security. However, this 'fish as food' perspective has yet to translate into policy and development funding priorities. We argue that the traditional framing of fish as a natural resource emphasizes economic development and biodiversity conservation objectives, whereas situating fish within a food systems perspective can lead to innovative policies and investments that promote nutrition-sensitive and socially equitable capture fisheries and aquaculture. This paper highlights four pillars of research needs and policy directions toward this end. Ultimately, recognizing and working to enhance the role of fish in alleviating hunger and malnutrition can provide an additional long-term development incentive, beyond revenue generation and biodiversity conservation, for governments, international development organizations, and society more broadly to invest in the sustainability of capture fisheries and aquaculture.


Assuntos
Pesqueiros , Abastecimento de Alimentos , Animais , Aquicultura , Conservação dos Recursos Naturais , Peixes , Políticas
5.
PLoS One ; 15(9): e0238574, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32877447

RESUMO

Large-scale marine protected areas (LSMPAs), MPAs greater than 100,000km2, have proliferated in the past decade. However, the value of LSMPAs as conservation tools is debated, in both global scientific and policy venues as well as in particular sites. To add nuance and more diverse voices to this debate, this research examines the perspectives of stakeholders directly engaged with LSMPAs. We conducted a Q Method study with forty LSMPA stakeholders at five sites, including three established LSMPAs (the Marianas Trench Marine National Monument, United States; the Phoenix Islands Protected Area, Kiribati; the National Marine Sanctuary, Palau) and two sites where LSMPAs had been proposed at the time of research (Bermuda and Rapa Nui (Easter Island), Chile). The analysis reveals five distinct viewpoints of LSMPAs. These include three more optimistic views of LSMPAs we have named Enthusiast, Purist, and Relativist. It also depicts two more cautious views of LSMPAs, which we have named Critic and Skeptic. The findings demonstrate the multi-dimensionality of stakeholder viewpoints on LSMPAs. These shared viewpoints have implications for the global LSMPA debate and LSMPA decision-makers, including highlighting the need to focus on LSMPA consultation processes. Better understanding of these viewpoints, including stakeholder beliefs, perspectives, values and concerns, may help to facilitate more nuanced dialogue amongst LSMPA stakeholders and, in turn, promote better governance of LSMPAs.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Participação dos Interessados
6.
Conserv Biol ; 23(2): 460-8, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19016824

RESUMO

Much has been written in recent years regarding whether and to what extent scientists should engage in the policy process, and the focus has been primarily on the issue of advocacy. Despite extensive theoretical discussions, little has been done to study attitudes toward and consequences of such advocacy in particular cases. We assessed attitudes toward science and policy advocacy in the case of marine protected areas (MPAs) on the basis of a survey of delegates at the First International Marine Protected Areas Congress. Delegates were all members of the international marine conservation community and represented academic, government, and nongovernmental organizations. A majority of respondents believed science is objective but only a minority believed that values can be eliminated from science. Respondents showed only partial support of positivist principles of science. Almost all respondents supported scientists being integrated into MPA policy making, whereas half of the respondents agreed that scientists should actively advocate for particular MPA policies. Scientists with a positivist view of science supported a minimal role for scientists in policy, whereas government staff with positivist beliefs supported an advocacy or decision-making role for scientists. Policy-making processes for MPAs need to account for these divergent attitudes toward science and advocacy if science-driven and participatory approaches are to be reconciled.


Assuntos
Conservação dos Recursos Naturais/métodos , Defesa do Consumidor , Ecossistema , Ciência , Coleta de Dados , Biologia Marinha , Oceanos e Mares , Organizações , Política Pública , Inquéritos e Questionários
7.
Pediatrics ; 137(2): e20153257, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26783326

RESUMO

BACKGROUND AND OBJECTIVES: Complicated vascular anomalies have limited therapeutic options and cause significant morbidity and mortality. This Phase II trial enrolled patients with complicated vascular anomalies to determine the efficacy and safety of treatment with sirolimus for 12 courses; each course was defined as 28 days. METHODS: Treatment consisted of a continuous dosing schedule of oral sirolimus starting at 0.8 mg/m(2) per dose twice daily, with pharmacokinetic-guided target serum trough levels of 10 to 15 ng/mL. The primary outcomes were responsiveness to sirolimus by the end of course 6 (evaluated according to functional impairment score, quality of life, and radiologic assessment) and the incidence of toxicities and/or infection-related deaths. RESULTS: Sixty-one patients were enrolled; 57 patients were evaluable for efficacy at the end of course 6, and 53 were evaluable at the end of course 12. No patient had a complete response at the end of course 6 or 12 as anticipated. At the end of course 6, a total of 47 patients had a partial response, 3 patients had stable disease, and 7 patients had progressive disease. Two patients were taken off of study medicine secondary to persistent adverse effects. Grade 3 and higher toxicities attributable to sirolimus included blood/bone marrow toxicity in 27% of patients, gastrointestinal toxicity in 3%, and metabolic/laboratory toxicity in 3%. No toxicity-related deaths occurred. CONCLUSIONS: Sirolimus was efficacious and well tolerated in these study patients with complicated vascular anomalies. Clinical activity was reported in the majority of the disorders.


Assuntos
Imunossupressores/uso terapêutico , Sirolimo/uso terapêutico , Malformações Vasculares/tratamento farmacológico , Administração Oral , Adolescente , Adulto , Criança , Pré-Escolar , Progressão da Doença , Feminino , Humanos , Imunossupressores/sangue , Lactente , Recém-Nascido , Masculino , Estudos Prospectivos , Qualidade de Vida , Sirolimo/sangue , Adulto Jovem
8.
PhytoKeys ; (21): 37-52, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23794935

RESUMO

Ten new combinations from Asagraea, Isidrogaliva, and Tofieldia are proposed in the previously monospecific genus Harperocallis (Tofieldiaceae, Alismatales). As circumscribed here, the genus is restricted to the Americas. The majority of species occur in the Andes or the Guayana region of northern South America; more than half have restricted distributions, and Harperocallis flava is narrowly endemic in the Coastal Plain of the southeastern United States. A key to species, synonymies, distributions, representative specimens, and salient notes are presented. Populations of the species are mapped and Harperocallis robustior is illustrated. A neotype is selected for Tofieldia frigida, here considered a synonym of Harperocallis falcata. Several recent records of Harperocallis longiflora, previously known only from the type collected in 1902, are reported.


ResúmenSe proponen diez nuevas combinaciones de Asagraea, Isidrogaliva, y Tofieldia en Harperocallis (Tofieldiaceae, Alismatales), un género previamente monoespecífico. Como se circunscribe aquí, el género se restringe a las Américas. La mayoría de las especies se encuentran en los Andes o en la región de Guayana en el norte de América del Sur. Más de la mitad tienen distribuciones restringidas, y Harperocallis flava es estrictamente endémica en la llanura costera del sudeste de los Estados Unidos. Se presenta una clave para distinguir las especies, sinonimias, distribuciones, muestras representativas y notas salientes. Se mapearon poblaciones de las especies y se ilustra Harperocallis robustior. Se seleccionó un neotipo para Tofieldia falcata, considerado aquí como un sinónimo de Harperocallis falcata. Se reportan algunos registros adicionales de Harperocallis longiflora, especie anteriormente conocida sólo con el tipo colectado en 1902.

9.
Environ Manage ; 38(1): 84-98, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16738822

RESUMO

As charismatic mega-fauna, sea turtles attract many volunteers to conservation programs. This article examines the ways in which volunteers value sea turtles, in the specific context of volunteers working with the Caribbean Conservation Corporation, at Tortuguero, Costa Rica. The complexity of volunteer values is explored using a qualitative approach. In-depth interviews with 31 volunteers were conducted in July of 1999 and 2000. Interviews probed, among other things, interest in sea turtles and their conservation, motives for participating, and the most gratifying parts of their volunteer experience. Results show that volunteers hold multiple and complex values for sea turtles, but particular values dominate. Results have implications for understanding human-environment relations and the emerging study of volunteer tourism. There are also management implications for volunteer programs hoping to attract participants.


Assuntos
Conservação dos Recursos Naturais , Valores Sociais , Tartarugas/fisiologia , Voluntários/psicologia , Animais , Costa Rica , Humanos
10.
Am J Bot ; 92(10): 1660-74, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21646083

RESUMO

(1→3),(1→4)-ß-Glucans had previously been detected in nonlignified cell wall preparations of only the Poaceae and five other families in the graminoid clade of the Poales (s.l.). Cell walls of vegetative organs of 12 species in nine families of the Poales (s.l.) were examined by immunogold labeling using a monoclonal antibody to (1→3),(1→4)-ß-glucans. Three types of wall-labeling patterns were identified depending on the density of labeling of the nonlignified walls of epidermal and parenchyma cells and the lignified walls of sclerenchyma fibers and xylem tracheary elements: type 1 in Poaceae and Flagellariaceae, type 2 in Restionaceae and Xyridaceae, and type 3 in Cyperaceae and Juncaceae. Type 1 had the heaviest labeling of nonlignified walls and type 2 the heaviest labeling of lignified walls. Type 3 had the least wall labeling, with only very light labeling of nonlignified and lignified walls. No labeling was found over walls of Typhaceae, Sparganiaceae, or Bromeliaceae. The results are discussed in relation to Poales phylogeny.

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