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1.
Med Anthropol Q ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847424

RESUMO

Cancer patients and survivors in the United States are increasingly likely to use online crowdfunding as a means of offsetting the expenses associated with their medical care. This practice of making an online appeal for support to a broad public audience constitutes an inadvertent form of informal emotional labor for its practitioners-labor in which striking the right affective notes in one's appeal is believed to be critical to fundraising outcomes. Drawing on ethnographic interviews, we suggest that crowdfunding produces an array of complex, often contradictory sentiments and narrative incentives for cancer patients and survivors-ultimately transforming the experience of serious illness.

2.
Nat Commun ; 12(1): 6634, 2021 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-34789722

RESUMO

Seasonal shifts in phytoplankton accumulation and loss largely follow changes in mixed layer depth, but the impact of mixed layer depth on cell physiology remains unexplored. Here, we investigate the physiological state of phytoplankton populations associated with distinct bloom phases and mixing regimes in the North Atlantic. Stratification and deep mixing alter community physiology and viral production, effectively shaping accumulation rates. Communities in relatively deep, early-spring mixed layers are characterized by low levels of stress and high accumulation rates, while those in the recently shallowed mixed layers in late-spring have high levels of oxidative stress. Prolonged stratification into early autumn manifests in negative accumulation rates, along with pronounced signatures of compromised membranes, death-related protease activity, virus production, nutrient drawdown, and lipid markers indicative of nutrient stress. Positive accumulation renews during mixed layer deepening with transition into winter, concomitant with enhanced nutrient supply and lessened viral pressure.


Assuntos
Fitoplâncton/fisiologia , Fitoplâncton/virologia , Água do Mar/microbiologia , Oceano Atlântico , Biomassa , Eutrofização , Estações do Ano , Água do Mar/química , Estresse Fisiológico , Fenômenos Fisiológicos Virais
3.
Limnol Oceanogr Methods ; 18(10): 570-584, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33132771

RESUMO

Phytoplankton accessory pigments are commonly used to estimate phytoplankton size classes, particularly during development and validation of biogeochemical models and satellite ocean color-based algorithms. The diagnostic pigment analysis (DPA) is based on bulk measurements of pigment concentrations and relies on assumptions regarding the presence of specific pigments in different phytoplankton taxonomic groups. Three size classes are defined by the DPA: picoplankton, nanoplankton, and microplankton. Until now, the DPA has not been evaluated against an independent approach that provides phytoplankton size calculated on a per-cell basis. Automated quantitative cell imagery of microplankton and some nanoplankton, used in combination with conventional flow cytometry for enumeration of picoplankton and nanoplankton, provide a novel opportunity to perform an independent evaluation of the DPA. Here, we use a data set from the North Atlantic Ocean that encompasses all seasons and a wide range of chlorophyll concentrations (0.18-5.14 mg m-3). Results show that the DPA overestimates microplankton and picoplankton when compared to cytometry data, and subsequently underestimates the contribution of nanoplankton to total biomass. In contrast to the assumption made by the DPA that the microplankton size class is largely made up of diatoms and dinoflagellates, imaging-in-flow cytometry shows significant presence of diatoms and dinoflagellates in the nanoplankton size class. Additionally, chlorophyll b is commonly attributed solely to picoplankton by the DPA, but Chl b-containing phytoplankton are observed with imaging in both nanoplankton and microplankton size classes. We suggest revisions to the DPA equations and application of uncertainties when calculating size classes from diagnostic pigments.

4.
J Geophys Res Oceans ; 124(11): 7557-7574, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32140375

RESUMO

High-performance liquid chromatography (HPLC) remains one of the most widely applied methods for estimation of phytoplankton community structure from ocean samples, which are used to create and validate satellite retrievals of phytoplankton community structure. HPLC measures the concentrations of phytoplankton pigments, some of which are useful chemotaxonomic markers for phytoplankton groups. Here, consistent suites of HPLC phytoplankton pigments measured on global surface water samples are compiled across spatial scales. The global dataset includes >4,000 samples from every major ocean basin and representing a wide range of ecological regimes. The local dataset is composed of six time series from long-term observatory sites. These samples are used to quantify the potential and limitations of HPLC for understanding surface ocean phytoplankton groups. Hierarchical cluster and empirical orthogonal function analyses are used to examine the associations between and among groups of phytoplankton pigments and to diagnose the main controls on these associations. These methods identify four major groups of phytoplankton on global scales (cyanobacteria, diatoms/dinoflagellates, haptophytes, and green algae) that can be identified by diagnostic biomarker pigments. On local scales, the same methods identify more and different taxonomic groups of phytoplankton than are detectable in the global dataset. Notably, diatom and dinoflagellate pigments group together on global scales, but dinoflagellate marker pigments always separate from diatoms on local scales. Together, these results confirm that HPLC pigments can be used for satellite algorithm quantification of no more than four phytoplankton groups on global scales, but can provide higher resolution for local-scale algorithm development and validation.

5.
PLoS One ; 12(6): e0177626, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28570610

RESUMO

Recycling human waste for beneficial use has been practiced for millennia. Aerobic (thermophilic) composting of sewage sludge has been shown to reduce populations of opportunistically pathogenic bacteria and to inactivate both Ascaris eggs and culturable Escherichia coli in raw waste, but there is still a question about the fate of most fecal bacteria when raw material is composted directly. This study undertook a comprehensive microbial community analysis of composting material at various stages collected over 6 months at two composting facilities in Haiti. The fecal microbiota signal was monitored using a high-density DNA microarray (PhyloChip). Thermophilic composting altered the bacterial community structure of the starting material. Typical fecal bacteria classified in the following groups were present in at least half the starting material samples, yet were reduced below detection in finished compost: Prevotella and Erysipelotrichaceae (100% reduction of initial presence), Ruminococcaceae (98-99%), Lachnospiraceae (83-94%, primarily unclassified taxa remained), Escherichia and Shigella (100%). Opportunistic pathogens were reduced below the level of detection in the final product with the exception of Clostridium tetani, which could have survived in a spore state or been reintroduced late in the outdoor maturation process. Conversely, thermotolerant or thermophilic Actinomycetes and Firmicutes (e.g., Thermobifida, Bacillus, Geobacillus) typically found in compost increased substantially during the thermophilic stage. This community DNA-based assessment of the fate of human fecal microbiota during thermophilic composting will help optimize this process as a sanitation solution in areas where infrastructure and resources are limited.


Assuntos
Bactérias/classificação , Esgotos , Bactérias/genética , Fezes/microbiologia , Haiti , Humanos , Microbiota , Filogenia , RNA Ribossômico 16S/genética
6.
Environ Urban ; 27(2): 525-540, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26640322

RESUMO

Household-level container-based sanitation (CBS) services may help address the persistent challenge of providing effective, affordable sanitation services for which low-income urban households are willing to pay. Little is known, however, about user perceptions of and demand for household CBS services. This study presents the results of a pilot CBS service programme in Cap Haitien, Haiti. One hundred and eighteen households were randomly selected to receive toilets and a twice-weekly collection service. After three months, changes in these households' satisfaction with their sanitation situation, along with feelings of pride, modernity and personal safety, were compared to 248 households in two comparison cohorts. Following the service pilot, 71 per cent of participating households opted to continue with the container-based sanitation service as paying subscribers. The results from this study suggest that, in the context of urban Haiti, household CBS systems have the potential to satisfy many residents' desire for safe, convenient and modern sanitation services.

7.
Environ Urban ; 27(1): 89-104, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26097288

RESUMO

Container-based sanitation (CBS) - in which wastes are captured in sealable containers that are then transported to treatment facilities - is an alternative sanitation option in urban areas where on-site sanitation and sewerage are infeasible. This paper presents the results of a pilot household CBS service in Cap Haitien, Haiti. We quantify the excreta generated weekly in a dense urban slum,(1) the proportion safely removed via container-based public and household toilets, and the costs associated with these systems. The CBS service yielded an approximately 3.5-fold decrease in the unmanaged share of faeces produced, and nearly eliminated the reported use of open defecation and "flying toilets" among service recipients. The costs of this pilot small-scale service were higher than those of large-scale waterborne sewerage, but economies of scale have the potential to reduce CBS costs over time. The paper concludes with a discussion of planning and policy implications of incorporating CBS into the menu of sanitation options for rapidly growing cities.

8.
Arch Environ Occup Health ; 67(4): 239-42, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23074981

RESUMO

An increased risk for obstructive sleep apnea (OSA) has been suggested for World Trade Center (WTC)-exposed workers. The authors reviewed the results from nocturnal polysomnograms (PSGs), to investigate diagnostic differences between WTC-exposed and -unexposed subjects. Six hundred fifty-six nocturnal PSGs performed at our sleep center were reviewed, 272 of them in former WTC workers. Seven diagnostic categories were compared between the 2 groups by bivariate and logistic regression analyses. The WTC group had a significantly higher predominance of the male gender, but slightly lower body mass index (BMI). There was no significant difference in the distribution of PSG diagnoses between the 2 groups in unadjusted (p = .56) or adjusted (p = .49) analyses. The authors did not identify a significant difference in PSG diagnoses between the WTC-exposed and -unexposed subjects. OSA was significantly associated with age, BMI, and gender in this patient population.


Assuntos
Socorristas , Doenças Profissionais/etiologia , Exposição Ocupacional/efeitos adversos , Polissonografia , Ataques Terroristas de 11 de Setembro , Apneia Obstrutiva do Sono/etiologia , Adulto , Fatores Etários , Idoso , Índice de Massa Corporal , Estudos de Casos e Controles , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/diagnóstico , Fatores de Risco , Fatores Sexuais , Apneia Obstrutiva do Sono/diagnóstico
9.
Pediatr Dermatol ; 23(5): 473-5, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17014645

RESUMO

We describe mycetoma caused by Microsporum canis occurring in a 9-year-old African-American girl. Pathologic evaluation showed a granulomatous dermatitis with numerous large fungal grains containing septate hyphae that were Fontana-Masson positive. Two cultures of pure grains grew M. canis. Mycetoma due to dermatophytes is very uncommon. The few instances reported have been pseudomycetoma (grains in the absence of sinus tracts). Our patient developed sinus tracts (true mycetoma). No prior reports were found of M. canis staining Fontana positive. Differentiation of dermatophyte-induced mycetoma from kerion is important because mycetomas require a combined approach including surgical debridement in addition to oral antifungal therapy.


Assuntos
Microsporum , Micetoma/microbiologia , Micetoma/patologia , Dermatoses do Couro Cabeludo/microbiologia , Dermatoses do Couro Cabeludo/patologia , Criança , Feminino , Humanos , Micetoma/terapia , Dermatoses do Couro Cabeludo/terapia , Nitrato de Prata
10.
Proc Natl Acad Sci U S A ; 103(12): 4522-7, 2006 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-16537377

RESUMO

Conventional agriculture has improved in crop yield but at large costs to the environment, particularly off-site pollution from mineral N fertilizers. In response to environmental concerns, organic agriculture has become an increasingly popular option. One component of organic agriculture that remains in question is whether it can reduce agricultural N losses to groundwater and the atmosphere relative to conventional agriculture. Here we report reduced N pollution from organic and integrated farming systems compared with a conventional farming system. We evaluated differences in denitrification potential and a suite of other soil biological and chemical properties in soil samples taken from organic, integrated, and conventional treatments in an experimental apple orchard. Organically farmed soils exhibited higher potential denitrification rates, greater denitrification efficiency, higher organic matter, and greater microbial activity than conventionally farmed soils. The observed differences in denitrifier function were then assessed under field conditions after fertilization. N(2)O emissions were not significantly different among treatments; however, N(2) emissions were highest in organic plots. Annual nitrate leaching was 4.4-5.6 times higher in conventional plots than in organic plots, with the integrated plots in between. This study demonstrates that organic and integrated fertilization practices support more active and efficient denitrifier communities, shift the balance of N(2) emissions and nitrate losses, and reduce environmentally damaging nitrate losses. Although this study specifically examines a perennial orchard system, the ecological and biogeochemical processes we evaluated are present in all agroecosystems, and the reductions in nitrate loss in this study could also be achievable in other cropping systems.


Assuntos
Agricultura , Poluição Ambiental , Fertilizantes/análise , Nitratos/metabolismo , Poluentes do Solo/metabolismo , Solo/análise , Ecossistema , Nitratos/análise , Poluentes do Solo/análise
13.
Cutis ; 73(2): 115-22, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15027517

RESUMO

Disseminated herpes or vaccinia in the setting of underlying skin diseases is known as Kaposi's varicelliform eruption (KVE). Patients typically present with disseminated vesicopustules in the areas of the most severe involvement of their underlying skin disease. We report a case of eczema herpeticum in a woman with a long-standing history of atopic dermatitis (AD). This report also reviews the literature on eczema herpeticum and eczema vaccinatum (EV), summarizes clinical and histopathologic characteristics and treatment, and discusses the recommendations of the Centers for Disease Control and Prevention for smallpox vaccination.


Assuntos
2-Aminopurina/análogos & derivados , Aciclovir/análogos & derivados , Erupção Variceliforme de Kaposi/patologia , Valina/análogos & derivados , 2-Aminopurina/administração & dosagem , 2-Aminopurina/uso terapêutico , Aciclovir/administração & dosagem , Aciclovir/uso terapêutico , Adulto , Antivirais/administração & dosagem , Antivirais/uso terapêutico , Diagnóstico Diferencial , Famciclovir , Feminino , Humanos , Erupção Variceliforme de Kaposi/tratamento farmacológico , Valaciclovir , Valina/administração & dosagem , Valina/uso terapêutico
14.
FEMS Microbiol Ecol ; 49(3): 469-79, 2004 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-19712295

RESUMO

Several tropical grasses harbor symbiotic nitrogen-fixing bacteria within their stem and rhizome tissue that may contribute to the nitrogen nutrition of the host plant. We present evidence here that sand dune grasses (Ammophila arenaria and Elymus mollis) from Oregon also contain nitrogen-fixing bacteria. Surface-sterilized stem and rhizome tissue from these species possess acetylene reduction (nitrogen fixation) activity and large populations (10(5) to 10(6) cfu/g fresh weight) of bacteria. These bacteria were cultured on N-free media and identified by sequencing of 16S rRNA genes or by GC-FAME. Random sequencing of numerous colonies from the initial isolation plates of mixed isolates showed that pseudomonads (Stenotrophomonas and Pseudomonas) were by far the most common microorganism. One isolate -Burkholderia sp. strain Aa1 - reduced acetylene in culture with maximum activity at an O(2) concentration of 2% (v/v) in liquid media or 10% on solid media. PCR screening of all the isolates with nifH and nifD primers was positive only for this species. Immunolocalization studies with antibodies to nitrogenase resulted in labeling within plant cell walls of stems and rhizomes. Evidence for a similar nitrogen-fixing association was also detected in Uniola paniculata (sea oats) and Ammophila brevigulata (American beachgrass). We conclude that these grasses, and probably other dune grasses from temperate climates, contain endophytic, diazotrophic bacteria that may contribute to the phenomenal success of these grasses on nutrient-poor sand.


Assuntos
Bactérias Gram-Negativas , Fixação de Nitrogênio , Nitrogenase/genética , Poaceae/microbiologia , Rizoma/microbiologia , Acetileno/metabolismo , Burkholderia/classificação , Burkholderia/genética , Burkholderia/isolamento & purificação , Burkholderia/metabolismo , DNA Ribossômico/análise , Genes de RNAr , Bactérias Gram-Negativas/classificação , Bactérias Gram-Negativas/genética , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Negativas/metabolismo , Imuno-Histoquímica , Microscopia Eletrônica de Transmissão , Nitrogenase/metabolismo , Oregon , Caules de Planta/microbiologia , Poaceae/classificação , Reação em Cadeia da Polimerase/métodos , Pseudomonas/classificação , Pseudomonas/genética , Pseudomonas/isolamento & purificação , Pseudomonas/metabolismo , RNA Ribossômico 16S , Rizoma/ultraestrutura , Stenotrophomonas/classificação , Stenotrophomonas/genética , Stenotrophomonas/isolamento & purificação , Stenotrophomonas/metabolismo , Simbiose
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