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1.
Proc Biol Sci ; 286(1895): 20182533, 2019 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-30963955

RESUMO

Mass stranding events (MSEs) of beaked whales (BWs) were extremely rare prior to the 1960s but increased markedly after the development of naval mid-frequency active sonar (MFAS). The temporal and spatial associations between atypical BW MSEs and naval exercises were first observed in the Canary Islands, Spain, in the mid-1980s. Further research on BWs stranded in association with naval exercises demonstrated pathological findings consistent with decompression sickness (DCS). A 2004 ban on MFASs around the Canary Islands successfully prevented additional BW MSEs in the region, but atypical MSEs have continued in other places of the world, especially in the Mediterranean Sea, with examined individuals showing DCS. A workshop held in Fuerteventura, Canary Islands, in September 2017 reviewed current knowledge on BW atypical MSEs associated with MFAS. Our review suggests that the effects of MFAS on BWs vary among individuals or populations, and predisposing factors may contribute to individual outcomes. Spatial management specific to BW habitat, such as the MFAS ban in the Canary Islands, has proven to be an effective mitigation tool and mitigation measures should be established in other areas taking into consideration known population-level information.


Assuntos
Som/efeitos adversos , Baleias/fisiologia , Animais , Dinâmica Populacional
2.
Sci Rep ; 4: 7031, 2014 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-25391309

RESUMO

Beaked whales are hypothesized to be particularly sensitive to anthropogenic noise, based on previous strandings and limited experimental and observational data. However, few species have been studied in detail. We describe the underwater behavior of a Baird's beaked whale (Berardius bairdii) from the first deployment of a multi-sensor acoustic tag on this species. The animal exhibited shallow (23 ± 15 m max depth), intermediate (324 ± 49 m), and deep (1138 ± 243 m) dives. Echolocation clicks were produced with a mean inter-click interval of approximately 300 ms and peak frequency of 25 kHz. Two deep dives included presumed foraging behavior, with echolocation pulsed sounds (presumed prey capture attempts) associated with increased maneuvering, and sustained inverted swimming during the bottom phase of the dive. A controlled exposure to simulated mid-frequency active sonar (3.5-4 kHz) was conducted 4 hours after tag deployment, and within 3 minutes of exposure onset, the tagged whale increased swim speed and body movement, and continued to show unusual dive behavior for each of its next three dives, one of each type. These are the first data on the acoustic foraging behavior in this largest beaked whale species, and the first experimental demonstration of a response to simulated sonar.


Assuntos
Migração Animal/efeitos da radiação , Mergulho/fisiologia , Ecolocação/fisiologia , Baleias/fisiologia , Estimulação Acústica , Migração Animal/fisiologia , Animais , Oceano Pacífico , Som
3.
J Exp Biol ; 217(Pt 14): 2449-55, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24803468

RESUMO

Low-frequency acoustic signals generated by baleen whales can propagate over vast distances, making the assignment of calls to specific individuals problematic. Here, we report the novel use of acoustic recording tags equipped with high-resolution accelerometers to detect vibrations from the surface of two tagged fin whales that directly match the timing of recorded acoustic signals. A tag deployed on a buoy in the vicinity of calling fin whales and a recording from a tag that had just fallen off a whale were able to detect calls acoustically but did not record corresponding accelerometer signals that were measured on calling individuals. Across the hundreds of calls measured on two tagged fin whales, the accelerometer response was generally anisotropic across all three axes, appeared to depend on tag placement and increased with the level of received sound. These data demonstrate that high-sample rate accelerometry can provide important insights into the acoustic behavior of baleen whales that communicate at low frequencies. This method helps identify vocalizing whales, which in turn enables the quantification of call rates, a fundamental component of models used to estimate baleen whale abundance and distribution from passive acoustic monitoring.


Assuntos
Acelerometria/métodos , Acústica/instrumentação , Baleia Comum/psicologia , Vocalização Animal , Animais , Monitoramento Ambiental/instrumentação , Oceanos e Mares
4.
Ecol Evol ; 2(6): 1260-77, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22833799

RESUMO

The major intention of the present study was to investigate whether an approach combining the use of niche-based palaeodistribution modeling and phylo-geography would support or modify hypotheses about the Quaternary distributional history derived from phylogeographic methods alone. Our study system comprised two closely related species of Alpine Primula. We used species distribution models based on the extant distribution of the species and last glacial maximum (LGM) climate models to predict the distribution of the two species during the LGM. Phylogeographic data were generated using amplified fragment length polymorphisms (AFLPs). In Primula hirsuta, models of past distribution and phylogeographic data are partly congruent and support the hypothesis of widespread nunatak survival in the Central Alps. Species distribution models (SDMs) allowed us to differentiate between alpine regions that harbor potential nunatak areas and regions that have been colonized from other areas. SDMs revealed that diversity is a good indicator for nunataks, while rarity is a good indicator for peripheral relict populations that were not source for the recolonization of the inner Alps. In P. daonensis, palaeo-distribution models and phylogeographic data are incongruent. Besides the uncertainty inherent to this type of modeling approach (e.g., relatively coarse 1-km grain size), disagreement of models and data may partly be caused by shifts of ecological niche in both species. Nevertheless, we demonstrate that the combination of palaeo-distribution modeling with phylogeographical approaches provides a more differentiated picture of the distributional history of species and partly supports (P. hirsuta) and partly modifies (P. daonensis and P. hirsuta) hypotheses of Quaternary distributional history. Some of the refugial area indicated by palaeodistribution models could not have been identified with phylogeographic data.

5.
J Exp Biol ; 214(Pt 1): 131-46, 2011 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-21147977

RESUMO

Lunge feeding by rorqual whales (Balaenopteridae) is associated with a high energetic cost that decreases diving capacity, thereby limiting access to dense prey patches at depth. Despite this cost, rorquals exhibit high rates of lipid deposition and extremely large maximum body size. To address this paradox, we integrated kinematic data from digital tags with unsteady hydrodynamic models to estimate the energy budget for lunges and foraging dives of blue whales (Balaenoptera musculus), the largest rorqual and living mammal. Our analysis suggests that, despite the large amount of mechanical work required to lunge feed, a large amount of prey and, therefore, energy is obtained during engulfment. Furthermore, we suggest that foraging efficiency for blue whales is significantly higher than for other marine mammals by nearly an order of magnitude, but only if lunges target extremely high densities of krill. The high predicted efficiency is attributed to the enhanced engulfment capacity, rapid filter rate and low mass-specific metabolic rate associated with large body size in blue whales. These results highlight the importance of high prey density, regardless of prey patch depth, for efficient bulk filter feeding in baleen whales and may explain some diel changes in foraging behavior in rorqual whales.


Assuntos
Balaenoptera/fisiologia , Metabolismo Energético/fisiologia , Comportamento Alimentar/fisiologia , Modelos Biológicos , Animais , Fenômenos Biomecânicos , Mergulho/fisiologia , Euphausiacea/fisiologia , Hidrodinâmica , Densidade Demográfica
6.
Gesundheitswesen ; 70(6): 364-71, 2008 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-18661460

RESUMO

OBJECTIVE: The aim of this study was to test the feasibility and acceptability of an intervention using text messaging (SMS) for continuous, individual support of smoking cessation. METHODS: Ninety-three socially deprived young adults were screened for smoking status and usage of text messaging in an institution for occupational rehabilitation. People who reported smoking daily and using text messaging at least weekly were invited to participate in a 12-week, SMS-based intervention. Individualised SMS-feedbacks were sent to the participants weekly, based on data from the baseline assessment and the weekly SMS assessment of the intention to quit smoking. Additionally, the participants could request SMS support whenever they suffered from withdrawal symptoms or craving. The intervention was based on the transtheoretical model of behaviour change (TTM). All of the 35 persons who met the inclusion criteria for the study registered for study participation; post-assessments were obtained from 33 participants. RESULTS: The average participant answered 8 of the 12 weekly SMS questions. The SMS-based questions and -feedbacks were evaluated as self-explanatory by the participants. At post-assessment, five participants (15%) reported occasional instead of daily smoking. None of the participants reported abstinence after the intervention. Pre-post comparisons revealed a reduction in the number of cigarettes smoked per day as well as in the heaviness of smoking and an increase in risk perception. No significant differences were found for situational urge to smoke and intention to change. CONCLUSION: The intervention proved to be feasible in a sample of socially deprived young adults, and was well accepted. The first results concerning its effectiveness are promising. The examination of this approach within a controlled study seems reasonable.


Assuntos
Carência Cultural , Avaliação de Programas e Projetos de Saúde , Abandono do Hábito de Fumar/métodos , Abandono do Hábito de Fumar/estatística & dados numéricos , Prevenção do Hábito de Fumar , Fumar/epidemiologia , Telemedicina/estatística & dados numéricos , Adulto , Telefone Celular/estatística & dados numéricos , Estudos de Viabilidade , Feminino , Alemanha/epidemiologia , Promoção da Saúde/métodos , Promoção da Saúde/estatística & dados numéricos , Humanos , Masculino , Projetos Piloto , Telemedicina/métodos
7.
Patient Educ Couns ; 63(3): 319-27, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16872793

RESUMO

OBJECTIVE: Due to a lack of valid German instruments measuring shared decision-making (SDM), a theory-driven questionnaire (SDM-Q) to measure the process of SDM was developed and validated. METHODS: As a theoretical basis steps of the SDM process were defined in an expert panel. Item formulation was then conducted according to the Delphi method. For the first validation on a mixed sample Rasch analysis was used to eliminate items not fitting the construct thus receiving a unidimensional scale. RESULTS: After eliminating 4 items the remaining 11 form a unidimensional scale with an acceptable reliability for person measures (0.77) and very good reliability for item difficulties (0.95). Analysis of subgroups revealed a different use of items in different conditions. Furthermore the scale showed high ceiling effects. CONCLUSION: A new theory-driven instrument to measure the process of SDM has been developed and validated by use of a rigorous method revealing first promising results. Yet the ceiling effects require the addition of more discriminating items, and the different use of items in different conditions demands an in depth analysis. PRACTICE IMPLICATIONS: While the concept of SDM is constantly receiving more attention in medical practice, its valid and reliable measurement remains challenging.


Assuntos
Tomada de Decisões , Participação do Paciente , Inquéritos e Questionários , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria , Reprodutibilidade dos Testes
8.
Tierarztl Prax ; 16(2): 163-5, 1988.
Artigo em Alemão | MEDLINE | ID: mdl-3420604

RESUMO

Serum iron concentration and iron-binding capacity were determined in 34 respectively 35 clinically healthy horses of different sex, with the age of 3 to 21 years. In the Warm blooded horse, the Half bred, the Haflinger horse, the Heavy horse and the Arabian Haflinger the mean serum iron concentration amounted to 253 +/- 66 micrograms/dl, 202 +/- 87 micrograms/dl, 166 +/- 67 micrograms/dl, 183 micrograms/dl and 366 micrograms/dl, while the iron-binding capacity in the Warm blooded horse, the Half bred, the Haflinger horse, the Thoroughbred, the Heavy horse and the Arabian Haflinger ran up to 427 +/- 55 micrograms/dl, 530 +/- 162 micrograms/dl, 422 +/- 63 micrograms/dl, 447 micrograms/dl, 467 micrograms/dl and 394 micrograms/dl. Regarding serum iron concentration no age or sex differences were ascertained, whereas they were obvious when observing the iron-binding capacity. Diurnal variations in serum iron concentration are pointed out. The quotient of the two examined parameters showed race-related differences. The results are presented in tables.


Assuntos
Cavalos/sangue , Ferro/sangue , Fatores Etários , Animais , Cruzamento , Ritmo Circadiano , Feminino , Ferro/metabolismo , Masculino , Valores de Referência , Fatores Sexuais
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