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1.
Cureus ; 13(8): e17224, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34540451

RESUMEN

Introduction Food insecurity directly influences health outcomes and is an important consideration for medical missions seeking to address chronic disease, particularly those serving disaster-prone communities. The region of Peru in which we held an inaugural mission is vulnerable to developing food insecurity following natural disasters. We, therefore, sought to evaluate food insecurity to understand the community's needs and inform future public health efforts. Methods In this cross-sectional pilot study, a convenience sample representing the households of patients attending a student-run health fair at the community medical center in Chincha, Peru was assessed for food insecurity. An adult female (n = 30) of each randomly selected family attending the fair was asked to complete the Household Food Security Survey (HFSS) developed by the US Department of Agriculture. The survey items were aggregated into a single, continuous food security scale reflecting the severity of hunger within a household. Results Two-thirds of respondents (n = 20) acknowledged anxiety about having enough food at home over the past 12 months, making it the most common concern. Nearly three in five respondents were concerned about their ability to provide a balanced diet. We found that 16.7% of all households were food insecure with severe hunger, 26.7% were food insecure with moderate hunger, 30% were food insecure without hunger, and 26.7% were food secure. Conclusion Nearly three-quarters of families attending our clinic experience some degree of food insecurity. Families with children were disproportionately affected. The high levels of food insecurity many years after a natural disaster support the development of future social programs such as food pantries. We intend to continue our partnership in Chincha and perform the HFSS survey on a periodic basis to monitor hunger.

2.
J Phycol ; 57(3): 903-915, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33587755

RESUMEN

Biological invasions have become increasingly prevalent in marine ecosystems, modifying biodiversity and altering the way ecosystems function. Understanding how variation in environmental factors influences the success of non-native species, especially their early life stages, can be a crucial step in identifying habitats that are under threat of invasion, and in predicting how rapidly and far these species may spread once they arrive in novel habitats. The invasive marine macroalga Sargassum horneri was first observed in Long Beach Harbor, CA, USA in 2003, and has since spread throughout the Southern California Bight and along the Baja California Peninsula, MEX where it now forms dense stands on subtidal rocky reefs and displaces native habitat-forming macroalgae. We examined how variation in temperature, nutrients, and irradiance affect survival, growth, and development in S. horneri early life stages over a three-week period. Our experimental treatments consisted of orthogonally crossed temperatures (10, 15, 20, and 25°C), nutrient concentrations (ambient and nutrient-enriched seawater), and irradiances (50 and 500 µmol photons · m-2 · s-1 ). Overall, temperature exerted the greatest influence on S. horneri's germling and juvenile life stages, with moderate temperatures facilitating their greatest survival, growth, and development. In contrast, fewer germlings developed fully under the lowest or highest temperatures, and juvenile survival and growth were reduced, especially when combined with low irradiances. Together, our data suggest that ocean temperatures of or below 10˚C and of or above 25°C may slow, but likely not stop, S. horneri's northward and southward expansion along the California and Baja California coasts.


Asunto(s)
Phaeophyceae , Sargassum , California , Ecosistema , México
3.
Biometals ; 32(1): 139-154, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30623317

RESUMEN

Phytoplankton blooms can cause acute effects on marine ecosystems due either to their production of endogenous toxins or to their enormous biomass leading to major impacts on local economies and public health. Despite years of effort, the causes of these Harmful Algal Blooms are still not fully understood. Our hypothesis is that bacteria that produce photoactive siderophores may provide a bioavailable source of iron for phytoplankton which could in turn stimulate algal growth and support bloom dynamics. Here we correlate iron concentrations, phytoplankton cell counts, bacterial cell abundance, and copy numbers for a photoactive siderophore vibrioferrin biosynthesis gene in water samples taken from 2017 cruises in the Gulf of California, and the Pacific Ocean off the coast of northern Baja California as well as during a multiyear sampling at Scripps Pier in San Diego, CA. We find that bacteria producing the photoactive siderophore vibrioferrin, make up a surprisingly high percentage of total bacteria in Pacific/Gulf of California coastal waters (up to 9%). Vibroferrin's unique properties and the widespread prevalence of its bacterial producers suggest that it may contribute significantly to generating bioavailability of iron via photoredox reactions.


Asunto(s)
Citratos/biosíntesis , Hierro/metabolismo , Marinobacter/química , Sideróforos/biosíntesis , California , Citratos/química , Hierro/química , Marinobacter/metabolismo , México , Pirrolidinonas/química , Sideróforos/química
4.
BMC Genomics ; 19(1): 701, 2018 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-30249182

RESUMEN

BACKGROUND: Life in the ocean will increasingly have to contend with a complex matrix of concurrent shifts in environmental properties that impact their physiology and control their life histories. Rhodoliths are coralline red algae (Corallinales, Rhodophyta) that are photosynthesizers, calcifiers, and ecosystem engineers and therefore represent important targets for ocean acidification (OA) research. Here, we exposed live rhodoliths to near-future OA conditions to investigate responses in their photosynthetic capacity, calcium carbonate production, and associated microbiome using carbon uptake, decalcification assays, and whole genome shotgun sequencing metagenomic analysis, respectively. The results from our live rhodolith assays were compared to similar manipulations on dead rhodolith (calcareous skeleton) biofilms and water column microbial communities, thereby enabling the assessment of host-microbiome interaction under climate-driven environmental perturbations. RESULTS: Under high pCO2 conditions, live rhodoliths exhibited positive physiological responses, i.e. increased photosynthetic activity, and no calcium carbonate biomass loss over time. Further, whereas the microbiome associated with live rhodoliths remained stable and resembled a healthy holobiont, the microbial community associated with the water column changed after exposure to elevated pCO2. CONCLUSIONS: Our results suggest that a tightly regulated microbial-host interaction, as evidenced by the stability of the rhodolith microbiome recorded here under OA-like conditions, is important for host resilience to environmental stress. This study extends the scarce comprehension of microbes associated with rhodolith beds and their reaction to increased pCO2, providing a more comprehensive approach to OA studies by assessing the host holobiont.


Asunto(s)
Microbiota , Rhodophyta/microbiología , Biodiversidad , Concentración de Iones de Hidrógeno , Metagenoma , Microbiota/genética , Océanos y Mares , Fotosíntesis , Rhodophyta/metabolismo , Rhodophyta/fisiología , Agua de Mar/química , Agua de Mar/microbiología , Estrés Fisiológico
5.
Oecologia ; 138(3): 436-47, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14673640

RESUMEN

Recent discussions on scaling issues in ecology have emphasized that processes acting at a wide range of spatial and temporal scales influence ecosystems and thus there is no appropriate single scale at which ecological processes should be studied. This may be particularly true for environmental disturbances (e.g. El Niño) that occur over large geographic areas and encompass a wide range of scales relevant to ecosystem function. However, it may be possible to identify the scale(s) at which ecosystems are most strongly impacted by disturbances, and thus provide a measure by which their impacts can be most clearly described, by assessing scale-dependent changes in the patterns of variability in species abundance and distribution. This, in turn, may yield significant insight into the relative importance of the various forcing factors responsible for generating these impacts. The 1997-98 El Niño was one of the strongest El Niños ever recorded. I examined how this event impacted giant kelp populations in the northeast Pacific Ocean at 90 sites ranging from central Baja California, Mexico to central California, USA. These sites spanned the geographic range of giant kelp in the Northeast Pacific and were surveyed just before, immediately following, several months after, more than 1 year after, and nearly 2 years after the El Niño. I used a hierarchical sample design to compare these impacts at five spatial scales spanning six orders of magnitude, from a few meters to more than 1,000 km. Variance Components Analyses revealed that the El Niño shifted control over giant kelp abundance from factors acting at the scale of a few meters (local control) to factors operating over hundreds to thousands of kilometers (regional control). Moreover, El Niño resulted in the near-complete loss of all giant kelp throughout one-half of the species' range in the northeast Pacific Ocean. Giant kelp recovery following El Niño was far more complex and variable at multiple spatial scales, presumably driven by numerous factors acting at those scales. Recovery returned local control of giant kelp populations within 6 months in southern California, and within 2 years in Baja California.


Asunto(s)
Kelp/crecimiento & desarrollo , Tiempo (Meteorología) , California , Ecosistema , Monitoreo del Ambiente , México , Océano Pacífico , Dinámica Poblacional
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