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1.
Proc Natl Acad Sci U S A ; 120(10): e2214035120, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36848574

RESUMO

Assessing environmental changes in Southern Ocean ecosystems is difficult due to its remoteness and data sparsity. Monitoring marine predators that respond rapidly to environmental variation may enable us to track anthropogenic effects on ecosystems. Yet, many long-term datasets of marine predators are incomplete because they are spatially constrained and/or track ecosystems already modified by industrial fishing and whaling in the latter half of the 20th century. Here, we assess the contemporary offshore distribution of a wide-ranging marine predator, the southern right whale (SRW, Eubalaena australis), that forages on copepods and krill from ~30°S to the Antarctic ice edge (>60°S). We analyzed carbon and nitrogen isotope values of 1,002 skin samples from six genetically distinct SRW populations using a customized assignment approach that accounts for temporal and spatial variation in the Southern Ocean phytoplankton isoscape. Over the past three decades, SRWs increased their use of mid-latitude foraging grounds in the south Atlantic and southwest (SW) Indian oceans in the late austral summer and autumn and slightly increased their use of high-latitude (>60°S) foraging grounds in the SW Pacific, coincident with observed changes in prey distribution and abundance on a circumpolar scale. Comparing foraging assignments with whaling records since the 18th century showed remarkable stability in use of mid-latitude foraging areas. We attribute this consistency across four centuries to the physical stability of ocean fronts and resulting productivity in mid-latitude ecosystems of the Southern Ocean compared with polar regions that may be more influenced by recent climate change.


Assuntos
Mudança Climática , Ecossistema , Animais , Regiões Antárticas , Efeitos Antropogênicos , Oceano Índico
2.
J Hered ; 114(6): 587-597, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37578073

RESUMO

The 20th century commercial whaling industry severely reduced populations of great whales throughout the Southern Hemisphere. The effect of this exploitation on genetic diversity and population structure remains largely undescribed. Here, we compare pre- and post-whaling diversity of mitochondrial DNA (mtDNA) control region sequences for 3 great whales in the South Atlantic, such as the blue, humpback, and fin whale. Pre-whaling diversity is described from mtDNA extracted from bones collected near abandoned whaling stations, primarily from the South Atlantic island of South Georgia. These bones are known to represent the first stage of 20th century whaling and thus pre-whaling diversity of these populations. Post-whaling diversity is described from previously published studies reporting large-scale sampling of living whales in the Southern Hemisphere. Despite relatively high levels of surviving genetic diversity in the post-whaling populations, we found evidence of a probable loss of mtDNA lineages in all 3 species. This is evidenced by the detection of a large number of haplotypes found in the pre-whaling samples that are not present in the post-whaling samples. A rarefaction analysis further supports a loss of haplotypes in the South Atlantic humpback and Antarctic blue whale populations. The bones from former whaling stations in the South Atlantic represent a remarkable molecular archive for further investigation of the decline and ongoing recovery in the great whales of the Southern Hemisphere.


Assuntos
DNA Mitocondrial , Baleias , Animais , Baleias/genética , DNA Mitocondrial/genética , Regiões Antárticas
3.
J Hered ; 111(3): 263-276, 2020 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-32347944

RESUMO

As species recover from exploitation, continued assessments of connectivity and population structure are warranted to provide information for conservation and management. This is particularly true in species with high dispersal capacity, such as migratory whales, where patterns of connectivity could change rapidly. Here we build on a previous long-term, large-scale collaboration on southern right whales (Eubalaena australis) to combine new (nnew) and published (npub) mitochondrial (mtDNA) and microsatellite genetic data from all major wintering grounds and, uniquely, the South Georgia (Islas Georgias del Sur: SG) feeding grounds. Specifically, we include data from Argentina (npub mtDNA/microsatellite = 208/46), Brazil (nnew mtDNA/microsatellite = 50/50), South Africa (nnew mtDNA/microsatellite = 66/77, npub mtDNA/microsatellite = 350/47), Chile-Peru (nnew mtDNA/microsatellite = 1/1), the Indo-Pacific (npub mtDNA/microsatellite = 769/126), and SG (npub mtDNA/microsatellite = 8/0, nnew mtDNA/microsatellite = 3/11) to investigate the position of previously unstudied habitats in the migratory network: Brazil, SG, and Chile-Peru. These new genetic data show connectivity between Brazil and Argentina, exemplified by weak genetic differentiation and the movement of 1 genetically identified individual between the South American grounds. The single sample from Chile-Peru had an mtDNA haplotype previously only observed in the Indo-Pacific and had a nuclear genotype that appeared admixed between the Indo-Pacific and South Atlantic, based on genetic clustering and assignment algorithms. The SG samples were clearly South Atlantic and were more similar to the South American than the South African wintering grounds. This study highlights how international collaborations are critical to provide context for emerging or recovering regions, like the SG feeding ground, as well as those that remain critically endangered, such as Chile-Peru.


Assuntos
Variação Genética , Baleias/genética , Distribuição Animal , Migração Animal , Animais , Brasil , Chile , Comportamento Alimentar , Feminino , Técnicas de Genotipagem , Ilhas , Masculino , Peru
4.
Proc Biol Sci ; 281(1786)2014 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-24850919

RESUMO

Humpback whales (Megaptera novaeangliae) annually undertake the longest migrations between seasonal feeding and breeding grounds of any mammal. Despite this dispersal potential, discontinuous seasonal distributions and migratory patterns suggest that humpbacks form discrete regional populations within each ocean. To better understand the worldwide population history of humpbacks, and the interplay of this species with the oceanic environment through geological time, we assembled mitochondrial DNA control region sequences representing approximately 2700 individuals (465 bp, 219 haplotypes) and eight nuclear intronic sequences representing approximately 70 individuals (3700 bp, 140 alleles) from the North Pacific, North Atlantic and Southern Hemisphere. Bayesian divergence time reconstructions date the origin of humpback mtDNA lineages to the Pleistocene (880 ka, 95% posterior intervals 550-1320 ka) and estimate radiation of current Northern Hemisphere lineages between 50 and 200 ka, indicating colonization of the northern oceans prior to the Last Glacial Maximum. Coalescent analyses reveal restricted gene flow between ocean basins, with long-term migration rates (individual migrants per generation) of less than 3.3 for mtDNA and less than 2 for nuclear genomic DNA. Genetic evidence suggests that humpbacks in the North Pacific, North Atlantic and Southern Hemisphere are on independent evolutionary trajectories, supporting taxonomic revision of M. novaeangliae to three subspecies.


Assuntos
Actinas/genética , Variação Genética , Jubarte/genética , Animais , Teorema de Bayes , Núcleo Celular/genética , DNA Mitocondrial/genética , Evolução Molecular , Haplótipos , Dados de Sequência Molecular , Oceanos e Mares , Filogenia , Análise de Sequência de DNA
5.
Sci Rep ; 14(1): 7493, 2024 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-38553485

RESUMO

Among large cetaceans in the Southern Hemisphere, fin whales were the most heavily exploited in terms of numbers taken during the period of intense industrial whaling. Recent studies suggest that, whilst some humpback whale populations in the Southern Hemisphere appears to have almost completely recovered to their estimated pre-whaling abundance, much less is known about the status of Southern Hemisphere fin whales. Circumpolar estimates in the 1990s suggest an abundance of about 5500 animals south of 60° S, while the IDCR/SOWER-2000 survey for the Scotia Sea and Antarctic Peninsula areas estimated 4670 fin whales within this region in the year 2000. More recent studies in smaller regions indicate higher densities, suggesting that previous estimates are overly conservative and/or that fin whales are undergoing a substantial increase. Here we report findings from a recent multi-vessel single-platform sightings survey carried out as part of the 2019 Area 48 Survey for Antarctic krill. While fin whales were encountered throughout the entire survey area, which covered the majority of CCAMLR Management Area 48, they were particularly abundant around the South Orkney Islands and the eastern Bransfield Strait. Large feeding aggregations were also encountered within the central Scotia Sea between South Orkney Islands and South Georgia. Distance sampling analyses suggest an average fin whale density throughout the Scotia Sea of 0.0256 ( CV = 0.149 ) whales per km2, which agrees well with recent density estimates reported from smaller sub-regions within the Scotia Sea. Design-based distance sampling analyses resulted in an estimated total fin whale abundance of 53,873 (CV = 0.15, 95% CI 40,233-72,138), while a density surface model resulted in a slightly lower estimate of 50,837 (CV: 0.136, 95% CI 38,966-66,324). These estimates are at least an order of magnitude greater than the previous estimate from the same region based on the IDCR/SOWER-2000 data, suggesting that fin whales are undergoing a substantial abundance increase in the South Atlantic. This may have important implications for the assessment of cetacean population trends, but also for CCAMLRs spatial overlap analysis process and efforts to implement a Feedback Management system for Antarctic krill. Our abundance estimate suggests an annual summer krill consumption by fin whales in the Antarctic Peninsula and Scotia Sea area of 7.97 (95% CI 4.94-11.91) million tonnes, which would represent around 20 times the total krill catch taken by the commercial fishery in Area 48 in the same season, or about 12.7% of the 2019 summer krill standing stock estimated from data collected during the same survey. This highlights the crucial importance of including cetacean krill predators in assessment and management efforts for living marine resources in the Southern Ocean, and particularly stresses the urgent need for a re-appraisal of abundance, distribution and ecological role of Southern Hemisphere fin whales.


Assuntos
Euphausiacea , Baleia Comum , Jubarte , Animais , Estações do Ano , Regiões Antárticas
6.
Zootaxa ; 3745: 551-68, 2013 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-25113370

RESUMO

A new deep-sea stalked barnacle, Vulcanolepas scotiaensis sp. nov. is described from hydrothermal vents at depths of 2400-2600 metres along segments of the East Scotia Ridge and from 1400 metres in the Kemp Caldera. Both locations are areas of volcanic activity that lie on the Antarctic-South American Ocean Ridge complex near the South Sandwich Islands. This discovery confirms a wide distribution in southern seas for Vulcanolepas, complementing the previous records from deep-sea vents in the Lau Basin and Kermadec Ridge in the southwest Pacific, and the Pacific Antarctic Ridge in the southeast Pacific. V. scotiaensis sp. nov., the third described species of Vulcanolepas shows an extraordinary range in morphology, requiring a reassessment of the original diagnosis for Vulcanolepas. Although the morphological envelope of V. scotiaensis sp. nov. includes representatives with a peduncle to capitulum ratio similar to that observed in most neolepadines, the peduncle generally shows greater proportional length than in species in any neolepadine genus except Leucolepas; it is distinguished from other species of Vulcanolepas by a broader capitulum, much smaller imbricating scales on the peduncle and more ornamented capitulum plates. The morphological diversity of V. scotiaensis sp. nov. is interpreted as having arisen due to abrupt changes in water temperature.LSID: urn:lsid:zoobank.org:act:AA2AFDA5-0B08-466A-A584-D3FDBDE9DA61.


Assuntos
Ecossistema , Thoracica/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Animais , Regiões Antárticas , Fontes Hidrotermais , Dados de Sequência Molecular , Filogenia , Thoracica/anatomia & histologia , Thoracica/genética
7.
Genes (Basel) ; 14(5)2023 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-37239398

RESUMO

Fin whales Balaenoptera physalus were hunted unsustainably across the globe in the 19th and 20th centuries, leading to vast reductions in population size. Whaling catch records indicate the importance of the Southern Ocean for this species; approximately 730,000 fin whales were harvested during the 20th century in the Southern Hemisphere (SH) alone, 94% of which were at high latitudes. Genetic samples from contemporary whales can provide a window to past population size changes, but the challenges of sampling in remote Antarctic waters limit the availability of data. Here, we take advantage of historical samples in the form of bones and baleen available from ex-whaling stations and museums to assess the pre-whaling diversity of this once abundant species. We sequenced 27 historical mitogenomes and 50 historical mitochondrial control region sequences of fin whales to gain insight into the population structure and genetic diversity of Southern Hemisphere fin whales (SHFWs) before and after the whaling. Our data, both independently and when combined with mitogenomes from the literature, suggest SHFWs are highly diverse and may represent a single panmictic population that is genetically differentiated from Northern Hemisphere populations. These are the first historic mitogenomes available for SHFWs, providing a unique time series of genetic data for this species.


Assuntos
Baleia Comum , Animais , Baleia Comum/genética , Baleias/genética , Densidade Demográfica , Regiões Antárticas
8.
Mol Phylogenet Evol ; 64(1): 243-53, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22503758

RESUMO

Lineages undergoing rapid radiations provide exceptional opportunities for studying speciation and adaptation, but also represent a challenge for molecular systematics because retention of ancestral polymorphisms and the occurrence of hybridization can obscure relationships among lineages. Dolphins in the subfamily Delphininae are one such case. Non-monophyly, rapid speciation events, and discordance between morphological and molecular characters have made the inference of phylogenetic relationships within this subfamily very difficult. Here we approach this problem by applying multiple methods intended to estimate species trees using a multi-gene dataset for the Delphininae (Sousa, Sotalia, Stenella, Tursiops, Delphinus and Lagenodelphis). Incongruent gene trees obtained indicate that incomplete lineage sorting and possibly hybridization are confounding the inference of species history in this group. Nonetheless, using coalescent-based methods, we have been able to extract an underlying species-tree signal from divergent histories of independent genes. This is the first time a molecular study provides support for such relationships. This study further illustrates how methods of species-tree inference can be very sensitive both to the characteristics of the dataset and the evolutionary processes affecting the evolution of the group under study.


Assuntos
Golfinhos/classificação , Golfinhos/genética , Evolução Molecular , Especiação Genética , Hibridização Genética , Modelos Genéticos , Filogenia , Animais , Sequência de Bases , Teorema de Bayes , Núcleo Celular/genética , Citocromos b/genética , Primers do DNA/genética , Funções Verossimilhança , Dados de Sequência Molecular , Análise de Sequência de DNA
9.
PLoS One ; 16(3): e0248071, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33662029

RESUMO

The diet of Antarctic fur seals (Arctocephalus gazella) at South Georgia is dominated by Antarctic krill (Euphausia superba). During the breeding season, foraging trips by lactating female fur seals are constrained by their need to return to land to provision their pups. Post-breeding, seals disperse in order to feed and recover condition; estimates indicate c.70% of females remain near to South Georgia, whilst others head west towards the Patagonian Shelf or south to the ice-edge. The krill fishery at South Georgia operates only during the winter, providing the potential for fur seal: fishery interaction during these months. Here we use available winter (May to September) tracking data from Platform Terminal Transmitter (PTT) tags deployed on female fur seals at Bird Island, South Georgia. We develop habitat models describing their distribution during the winters of 1999 and 2003 with the aim of visualising and quantifying the degree of spatial overlap between female fur seals and krill harvesting in South Georgia waters. We show that spatial distribution of fur seals around South Georgia is extensive, and that the krill fishery overlaps with small, highly localised areas of available fur seal habitat. From these findings we discuss the implications for management, and future work.


Assuntos
Euphausiacea/fisiologia , Pesqueiros , Otárias/fisiologia , Distribuição Animal , Migração Animal , Animais , Ilhas Atlânticas , Oceano Atlântico , Cruzamento , Ecossistema , Feminino , Ilhas , Masculino , Estações do Ano
10.
JASA Express Lett ; 1(6): 061202, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-36154373

RESUMO

Southern right whale vocalizations were recorded concurrently with visual observations off the sub-Antarctic Island of South Georgia, and the characteristics of these calls were described. Calls were also compared to those of humpback whales at South Georgia, to determine how the two species might reliably be distinguished acoustically. The southern right whale calls measured (which were all upcalls) had lower frequency with peak energy and were mostly shorter in duration than the calls measured from humpback whales. The frequency upsweep and the lack of harmonics of southern right whale calls were also diagnostic characteristics.


Assuntos
Jubarte , Animais , Regiões Antárticas
11.
Mol Ecol ; 19(2): 281-91, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20025655

RESUMO

Severe declines in megafauna worldwide illuminate the role of top predators in ecosystem structure. In the Antarctic, the Krill Surplus Hypothesis posits that the killing of more than 2 million large whales led to competitive release for smaller krill-eating species like the Antarctic minke whale. If true, the current size of the Antarctic minke whale population may be unusually high as an indirect result of whaling. Here, we estimate the long-term population size of the Antarctic minke whale prior to whaling by sequencing 11 nuclear genetic markers from 52 modern samples purchased in Japanese meat markets. We use coalescent simulations to explore the potential influence of population substructure and find that even though our samples are drawn from a limited geographic area, our estimate reflects ocean-wide genetic diversity. Using Bayesian estimates of the mutation rate and coalescent-based analyses of genetic diversity across loci, we calculate the long-term population size of the Antarctic minke whale to be 670,000 individuals (95% confidence interval: 374,000-1,150,000). Our estimate of long-term abundance is similar to, or greater than, contemporary abundance estimates, suggesting that managing Antarctic ecosystems under the assumption that Antarctic minke whales are unusually abundant is not warranted.


Assuntos
Genética Populacional , Baleia Anã/genética , Modelos Genéticos , Animais , Teorema de Bayes , Simulação por Computador , Conservação dos Recursos Naturais , Ligação Genética , Marcadores Genéticos , Variação Genética , Geografia , Método de Monte Carlo , Mutação , Densidade Demográfica , Recombinação Genética , Análise de Sequência de DNA
12.
Front Plant Sci ; 11: 502359, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32983208

RESUMO

Biogeographic patterns of globally widespread species are expected to reflect regional structure, as well as connectivity caused by occasional long-distance dispersal. We assessed the level and drivers of population structure, connectivity, and timescales of population isolation in one of the most widespread and ruderal plants in the world - the common moss Ceratodon purpureus. We applied phylogenetic, population genetic, and molecular dating analyses to a global (n = 147) sampling data set, using three chloroplast loci and one nuclear locus. The plastid data revealed several distinct and geographically structured lineages, with connectivity patterns associated with worldwide, latitudinal "bands." These imply that connectivity is strongly influenced by global atmospheric circulation patterns, with dispersal and establishment beyond these latitudinal bands less common. Biogeographic patterns were less clear within the nuclear marker, with gene duplication likely hindering the detection of these. Divergence time analyses indicated that the current matrilineal population structure in C. purpureus has developed over the past six million years, with lineages diverging during the late Miocene, Pliocene, and Quaternary. Several colonization events in the Antarctic were apparent, as well as one old and distinct Antarctic clade, possibly isolated on the continent since the Pliocene. As C. purpureus is considered a model organism, the matrilineal biogeographic structure identified here provides a useful framework for future genetic and developmental studies on bryophytes. Our general findings may also be relevant to understanding global environmental influences on the biogeography of other organisms with microscopic propagules (e.g., spores) dispersed by wind.

13.
Prev Med Rep ; 14: 100829, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30949424

RESUMO

Food insecurity among U.S. older adults has more than doubled since 2001 and is higher in those who are frail. Given the growing aging population and the importance of physical functioning and adequate food intake, the increase in food insecurity is a public health concern. This study examined the association between domains of physical limitations and food security in U.S. older adults. Data were from the National Health and Nutrition Examination Survey (2007-2012) participants 60 years of age and older (n = 5969). Physical limitations were defined as some or much difficulty on 19 activities, categorized into 5 domains and an index score. Food security status was categorized as full, marginal, low, or very low, and also dichotomized into food secure and food insecure (marginal, low, or very low food security). Multinomial and logistic regression models were used to estimate odds ratios (OR) and adjusted ORs (aOR) with food security as the dependent variable and physical limitations as independent variables. Older adults with 4 or more physical limitations were more likely to report very low food security than older adults without limitations (aOR:2.62, 95% CI:1.43, 4.81). The strongest correlates of food insecurity were Instrumental Activities of Daily Living (aOR:1.49; 95% CI:1.10, 2.01), Leisure and Social Activities (aOR:1.56; 95% CI:1.37, 2.14), and General Physical Activities (aOR:1.50; 95% CI:1.08, 2.07). Physical functioning is important for food security among older adults. Interventions should incorporate assessment of physical functioning, and provide resources for food acquisition, preparation, and intake for older adults with physical limitations.

14.
R Soc Open Sci ; 6(10): 190368, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31824687

RESUMO

The recovery of whale populations from centuries of exploitation will have important management and ecological implications due to greater exposure to anthropogenic activities and increasing prey consumption. Here, a Bayesian population model integrates catch data, estimates of abundance, and information on genetics and biology to assess the recovery of western South Atlantic (WSA) humpback whales (Megaptera novaeangliae). Modelling scenarios evaluated the sensitivity of model outputs resulting from the use of different data, different model assumptions and uncertainty in catch allocation and in accounting for whales killed but not landed. A long period of exploitation drove WSA humpback whales to the brink of extinction. They declined from nearly 27 000 (95% PI = 22 800-33 000) individuals in 1830 to only 450 (95% PI = 200-1400) whales in the mid-1950s. Protection led to a strong recovery and the current population is estimated to be at 93% (95% PI = 73-100%) of its pre-exploitation size. The recovery of WSA humpback whales may result in large removals of their primary prey, the Antarctic krill (Euphausia superba), and has the potential to modify the community structure in their feeding grounds. Continued monitoring is needed to understand how these whales will respond to modern threats and to climate-driven changes to their habitats.

15.
PLoS One ; 14(10): e0222498, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31622348

RESUMO

We test the ability of Very High Resolution satellite (VHR) imagery to detect stranded whales using both manual and automated methods. We use the 2015 mass mortality event in the Gulf of Penas locality, central Patagonia, Chile, as an initial case study. This event was the largest known mass mortality of baleen whales, with at least 343 whales, mainly sei whales (Balaenoptera borealis), documented as stranding. However, even with such a large number of whales, due to the remote location of the gulf the strandings went unrecorded for several weeks. Aerial and boat surveys of the area were conducted two to four months after the mortality event. In this study we use 50cm resolution WorldView2 imagery to identify and count strandings from two archival images acquired just after the stranding event and two months before the aerial and ground surveys, and to test manual and automated methods of detecting stranded whales. Our findings show that whales are easily detected manually in the images but due to the heterogeneous colouration of decomposing whales, spectral indices are unsuitable for automatic detection. Our satellite counts suggest that, at the time the satellite images were taken, more whales were stranded than recorded in the aerial survey, possibly due to the non-comprehensive coverage of the aerial survey or movement of the carcases between survey acquisition. With even higher resolution imagery now available, satellite imagery may be a cost effective alternative to aerial surveys for future assessment of the extent of mass whale stranding events, especially in remote and inaccessible areas.


Assuntos
Balaenoptera/fisiologia , Monitoramento Ambiental , Tecnologia de Sensoriamento Remoto , Animais , Chile , Humanos , Mortalidade , Imagens de Satélites/métodos
17.
PLoS One ; 12(1): e0168646, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28081160

RESUMO

Since 1970, blue whales (Balaenoptera musculus) have been seen feeding in the waters off southern Chile during the summer and autumn (December to May). Investigation of the genetic, acoustic and morphological characteristics of these blue whales shows that they are a distinct but unnamed subspecies, called the Chilean blue whales. Photo-identification surveys have been conducted in the waters off northwestern Isla Grande de Chiloé, southern Chile from 2004-2012 and Isla Chañaral, central Chile in 2012. Over this time, 1,070 blue whales were encountered yielding, after photo-quality control, 318 and 267 unique photographs of the left and right side of the flank respectively. Using mark-recapture analysis of left and right side photographs collected from Isla Grande de Chiloé (2004-2012), open population models estimate that ~570-760 whales are feeding seasonally in this region. POPAN superpopulation abundance estimates for the same feeding ground in 2012 are 762 (95% confidence intervals, CI = 638-933) and 570 (95% CI 475-705) for left and right side datasets respectively, very similar to results from closed population models. Estimates of trend revealed strong variation in abundance, peaking in 2009 and [suggesting] fluctuating use in the survey area over time, likely related to the density of their prey. High inter-annual return rates suggest a degree of site-fidelity of individuals to Isla Grande de Chiloé and that the number of whales using this feeding ground is relatively small.


Assuntos
Balaenoptera/fisiologia , Bases de Dados Factuais , Animais , Chile , Feminino , Masculino , Dinâmica Populacional , Estações do Ano
18.
Health Educ Behav ; 44(4): 648-657, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28125908

RESUMO

BACKGROUND: Family homes are a key setting for developing lifelong eating and physical activity habits, yet little is known about how family home nutrition and physical activity (FNPA) environments influence food insecurity (FI) and childhood obesity, particularly in rural settings. AIMS: This study examined associations among FNPA, FI, and body mass index (BMI) in rural children. METHOD: Parents of 186 elementary school-age children completed FNPA and FI surveys. Child anthropometrics were directly measured. Logistic and linear regressions were used to examine associations. RESULTS: Approximately 37% of children were overweight/obese; 43% of families were at risk for FI. Children whose families limited watching TV while eating were less likely to be obese (odds ratio [OR] = 0.56, p = .03) as were children whose families monitored intake of chips, cookies, and candy (OR = 0.54, p = .01). FI was higher in obese than normal weight children (OR = 11.00, p = .003) but only among families not eligible to receive free/reduced-cost school meals. Among eligible families, lower odds of FI were found for those who ate meals together often (OR = 0.31, p = .04) and for those with children frequently enrolled in organized sports/activities (OR = 0.65, p = .04). Findings were not significant after adjusting for multiple comparisons. DISCUSSION: Results suggest that favorable FNPA factors were associated with healthier BMI and lower odds of FI. CONCLUSION: Opportunities for healthy eating at home may support rural children's weight health. Additional resources may be necessary to promote food security among low-income families. Future research is warranted to better understand FNPA in relationship to the disproportionate rates of obesity and FI in rural populations.


Assuntos
Índice de Massa Corporal , Abastecimento de Alimentos , Avaliação Nutricional , População Rural , Criança , Dieta , Exercício Físico/fisiologia , Comportamento Alimentar , Feminino , Humanos , Masculino , Obesidade Infantil , Pobreza , Inquéritos e Questionários
19.
Nucleic Acids Res ; 31(21): 6354-64, 2003 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-14576323

RESUMO

AT-rich minisatellites (AT islands) are sites of genomic instability in cancer cells and targets for extremely lethal AT-specific drugs, such as bizelesin. Here we investigated the AT islands in the FRA16B fragile site region for their possible roles in the organization of DNA on the nuclear matrix. The FRA16B AT island nominally spans approximately 3 kb of mostly >90% A/T DNA. In silico analysis indicates that this domain exhibits characteristics of nuclear matrix attachment regions (MARs): an exceptionally intense computed 'MAR potential' and profound duplex destabilization and flexibility. FRA16B repeats specifically bind to isolated nuclear matrices, which indicates their in vitro MAR function. This binding is several-fold greater than that of a known MAR in the c-myc gene. AT islands in fragile sites FRA16B and FRA16D are significantly more abundant in CEM cells that are hypersensitive to bizelesin compared to normal WI-38 cells. FRA16B overabundance in CEM is due to an approximately 10-fold expansion of FRA16B repeats. The expanded FRA16B minisatellites in CEM cells preferentially localize to the nuclear matrix-associated DNA indicating their in vivo MAR function. The unexpanded repeats in WI-38 cells localize to the loop DNA. The c-myc MAR is also matrix-associated in CEM cells while localizing to loop DNA in WI-38 cells. These results are the first to demonstrate that AT islands in fragile sites can function as MARs both in vitro and in vivo. The ability of FRA16B-mediated MAR sites to rearrange depending on the repeat expansion status could be relevant to both genomic instability of cancer cells and their sensitivity to AT-island targeting drugs.


Assuntos
Sequência Rica em At/genética , Fragilidade Cromossômica/genética , Sequência de DNA Instável/genética , DNA/metabolismo , Leucemia/genética , Repetições Minissatélites/genética , Matriz Nuclear/metabolismo , Ureia/análogos & derivados , Sítios de Ligação , Linhagem Celular Tumoral , Cromossomos Humanos Par 16/genética , DNA/química , DNA/genética , Duocarmicinas , Genes myc/genética , Globinas/genética , Humanos , Indóis/farmacologia , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Reação em Cadeia da Polimerase , Ureia/farmacologia
20.
J Sch Health ; 86(1): 39-47, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26645419

RESUMO

BACKGROUND: Practical tools are needed that reliably measure the complex physical activity (PA) and nutrition environments of elementary schools that influence children's health and learning behaviors for obesity prevention. The School Physical Activity and Nutrition-Environment Tool (SPAN-ET) was developed and beta tested in 6 rural Oregon elementary schools. METHODS: Extension educators were trained to assess elementary school PA and nutrition environments using the SPAN-ET. Two auditors per school worked with school health stakeholders and collected data via document review, interviews, and direct observations. A reliability analysis using percent agreement and kappa statistics was performed to determine consistency between independent auditors. Content analyses of qualitative data were used to triangulate intercoder ratings, verify evidence, and improve reliability. RESULTS: Across the 6 schools, for all 182 measured criteria (PA = 103; nutrition = 79), the percent agreement ranged from 80.8% to 96.8% and kappa from 0.61% to 0.94. CONCLUSION: The SPAN-ET was a reliable instrument for assessing the quality of elementary school PA and nutrition environments, and a sensitive measure for objectively identifying specific attributes of SPAN-ET areas of interest to target for school environmental and policy improvements aimed at supporting students' obesity preventing behaviors.


Assuntos
Serviços de Alimentação , Promoção da Saúde , Educação Física e Treinamento , Serviços de Saúde Escolar , Criança , Exercício Físico , Feminino , Humanos , Entrevistas como Assunto , Masculino , Obesidade/prevenção & controle , Observação , Oregon , Pesquisa Qualitativa , Instituições Acadêmicas
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