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3.
Biol Lett ; 16(1): 20190760, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31964259

RESUMO

Broadcast-spawning scleractinian corals annually release their gametes with high levels of synchrony, both within and among species. However, the timing of spawning can vary inter-annually. In particular, the night of spawning relative to the full moon phase can vary considerably among years at some locations. Although multiple environmental factors can affect the night of spawning, their effects have not been quantitatively assessed at the multi-regional level. In this study, we analysed environmental factors that are potentially correlated with spawning day deviation, in relation to the full moon phase, in Acropora corals inhabiting seven reefs in Australia and Japan. We accordingly found that sea surface temperature and wind speed within one to two months prior to the full moon of the spawning month were strongly correlated with spawning day deviations. In addition, solar flux had a weak effect on the night of spawning. These findings indicate that Acropora have the capacity to adjust their development and physiology in response to environmental factors for fine-tuning the timing of synchronous spawning, thereby maximizing reproductive success and post-fertilization survival.


Assuntos
Antozoários , Animais , Austrália , Recifes de Corais , Japão , Lua , Reprodução
4.
J Psychiatr Pract ; 25(6): 475-480, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31821226

RESUMO

According to a recent report, mood cycles in a group of patients with rapid cycling bipolar disorder oscillated in synchrony with lunar gravimetric tides. Mood switches in a 67-year-old woman with rapid cycling bipolar II disorder on lithium maintenance treatment were assessed with a χ periodogram and a χ analysis of the mood switches in relation to the lunar tidal cycle. During a period when she was treated with nortriptyline and her thyroid-stimulating hormone levels were elevated, her mood switches had a significant (P<0.05) 29- to 30-day periodicity, and the χ analysis showed that the switches were distributed nonrandomly in relation to the spring-neap lunar tidal cycle (P<0.0001); 14 of 15 switches occurred within 2 days of the spring tides. After nortriptyline was discontinued, thyroid-stimulating hormone levels were normalized with treatment with levothyroxine, and consistent bright light treatment was started, the synchrony between mood cycles and lunar cycles disappeared, and rapid cycling eventually stopped. The possibility that lunar mood cycling is sometimes contingent on antidepressant treatment, decreased thyroid function, and certain types of light-dark cycles needs to be considered in future research on lunar tidal influences on the course of bipolar illness.


Assuntos
Transtorno Bipolar , Hipotireoidismo , Afeto , Idoso , Feminino , Humanos , Lua , Tiroxina
6.
Science ; 366(6465): 581, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31672886
7.
PLoS Biol ; 17(10): e3000456, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31613884

RESUMO

Every year, billions of seasonal migrants connect continents by transporting nutrients, energy, and pathogens between distant communities and ecosystems. For animals that power their movements by endogenous energy stores, the daily energy intake rates strongly influence the speed of migration. If access to food resources varies cyclically over the season, migrants sensitive to changes in daily energy intake rates may adjust timing of migration accordingly. As an effect, individuals adjusting to a common temporal cycle are expected to approach synchrony in foraging and movement. A large-scale periodic pattern, such as the dark-light cycle of the moon, could thus synchronize migrations across animal populations. However, such cyclic effects on the temporal regulation of migration has not been considered. Here, we show the temporal influence of the lunar cycle on the movement activity and migration tactics in a visual hunting nocturnal insectivore and long-distance migrant, the European nightjar, Caprimulgus europeaus. We found that the daily foraging activity more than doubled during moonlit nights, likely driven by an increase in light-dependent fuelling opportunities. This resulted in a clear cyclicity also in the intensity of migratory movements, with occasionally up to 100% of the birds migrating simultaneously following periods of full moon. We conclude that cyclic influences on migrants can act as an important regulator of the progression of individuals and synchronize pulses of migratory populations, with possible downstream effects on associated communities and ecosystems.


Assuntos
Migração Animal/fisiologia , Aves/fisiologia , Lua , Periodicidade , África , Animais , Ecossistema , Ingestão de Energia/fisiologia , Europa (Continente) , Feminino , Cadeia Alimentar , Insetos , Masculino , Fotoperíodo
8.
Sci Total Environ ; 692: 589-594, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31539966

RESUMO

BACKGROUND: Several studies have reported an association between seizure and the lunar cycle; however, results are conflicting. Thus, we investigated whether emergency department (ED) visits due to febrile seizure (FS) or FS plus were affected by lunar cycle. METHODS: We reviewed the medical records of patients who were admitted to the ED with a main diagnosis of FS or FS plus from January 1, 2005 to August 31, 2018 (13 years 8 months), a period of 4991 days with 169 lunar cycles. During that period, we collected weather data such as mean temperature, average atmospheric pressure (AP), and humidity according to lunar phase (new moon, first quarter, full moon, and third or last quarter). RESULTS: A total of 1979 patients were identified. We found male predominant with a mean age of 2.62 ±â€¯2.09 years. Acute pharyngotonsillitis was the most common cause of fever, generalized tonic-clonic seizure was the most common type of seizure, and the mean peak body temperature was 38.77 ±â€¯0.81 °C. The lunar cycle did not affect the onset or frequency of FS after adjustment; however, several factors, including season, O3 and NO2 concentrations, and holidays, were associated with FS. CONCLUSION: We did not find an association between lunar cycle and FS or FS plus. However, several factors, including season, O3, NO2, and holidays were associated with FS or FS plus.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Lua , Convulsões Febris/epidemiologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , República da Coreia/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Convulsões Febris/etiologia , Fatores de Tempo
9.
Med J Aust ; 211(6): 271-276, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31420881

RESUMO

Space flight presents a set of physiological challenges to the space explorer which result from the absence of gravity (or in the case of planetary exploration, partial gravity), radiation exposure, isolation and a prolonged period in a confined environment, distance from Earth, the need to venture outside in the hostile environment of the destination, and numerous other factors. Gravity affects regional lung function, and the human lung shows considerable alteration in function in low gravity; however, this alteration does not result in deleterious changes that compromise lung function upon return to Earth. The decompression stress associated with extravehicular activity, or spacewalk, does not appear to compromise lung function, and future habitat (living quarter) designs can be engineered to minimise this stress. Dust exposure is a significant health hazard in occupational settings such as mining, and exposure to extraterrestrial dust is an almost inevitable consequence of planetary exploration. The combination of altered pulmonary deposition of extraterrestrial dust and the potential for the dust to be highly toxic likely makes dust exposure the greatest threat to the lung in planetary exploration.


Assuntos
Medicina Aeroespacial , Pulmão/fisiologia , Modelos Biológicos , Voo Espacial , Humanos , Lua
12.
Nature ; 571(7764): 177-178, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31292554
16.
PLoS One ; 14(7): e0220255, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31335883

RESUMO

Several external factors including lunar cycle and weather conditions might be associated with calving conditions. Our objective here was to determine the effects of lunar cycle and weather conditions on calving frequency and the occurrence of preterm calving in Japanese Black cows. Calving records were obtained from 905 farms in Miyazaki Prefecture, Japan. Data were collected from 41,116 calvings. We conducted two studies: Study 1 investigated the effects of lunar cycle and weather conditions on daily calving frequency (DCF) with the observational unit of each day and Study 2 investigated those effects on the occurrence of preterm calving with the observational unit for each calving. Preterm calving was defined by whether or not a cow calving before 280 days of gestation, lower 10th percentile of gestation length of the collected data, and by whether or not a cow calving before 289 days of gestation, median of the gestation length. For Study 1, lunar cycle was not associated with DCF in all cows, in only primiparous cows and in only multiparous cows. As well as lunar cycle, weather conditions such as temperature, diurnal temperature variation, the temperature-humidity index, precipitation amount, barometric pressure, relative humidity and solar radiation, were also not associated with DCF. For Study 2, lunar cycle phases were not associated with the occurrence of preterm calving. However, preterm calving was associated with all of the weather conditions (P < 0.05) except for precipitation amounts and solar radiation. Temperature, the temperature-humidity index and relative humidity were positively associated with the occurrence of preterm calving. In contrast, diurnal temperature variations and barometric pressure were negatively associated with the occurrence of preterm calving. In conclusion, the lunar cycle was not associated with DCF and preterm calving, but the weather conditions were associated with preterm calving.


Assuntos
Bovinos/fisiologia , Lua , Prenhez/fisiologia , Tempo (Meteorologia) , Animais , Feminino , Gravidez
17.
PLoS One ; 14(6): e0212716, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31216280

RESUMO

Animals making foraging decisions must balance the energy gained, the time invested, and the influence of key environmental factors. In our work, we examined the effect of predation risk cues and experience on feeding efforts when a novel food resource was made available. To achieve this, we live-trapped wood mouse Apodemus sylvaticus in Monte de Valdelatas (Madrid), where 80 Sherman traps were set in four plots. Traps were subjected to two food-access difficulties in treatments consisting of three consecutive nights: open plastic bottles (easy) and closed bottles (difficult), both using corn as bait. To simulate predation risk, we set fox faeces in half of the traps in each plot. We also considered moonlight (medium/low) as an indirect predation risk cue. We analysed whether bottles had been bitten by mice and the gnawed area of each bottle was measured. Our results indicated that food access difficulty, experience, and predation risk determined mice feeding decisions and efforts. The ability of mice to adapt feeding effort when a new food source is available was demonstrated because a higher proportion of closed bottles exhibited bite marks and the gnawed area was bigger. Moreover, mouse experience was determinant in the use of this new resource since recaptured mice gnawed broader orifices in the bottles and the gnawed area increased each time an individual was recaptured. Additionally, direct predation risk cues prompted mice to bite the bottles whereas the effect of different moon phases varied among the food access treatments. This study provides direct evidence of formidable efficacy of wild mice to exploit a new nutrient resource while considering crucial environmental factors that shape the decision-making procedure.


Assuntos
Tomada de Decisões , Comportamento Alimentar/psicologia , Animais , Comportamento Apetitivo , Comportamento Animal , Sinais (Psicologia) , Fezes , Alimentos , Raposas , Camundongos , Lua , Risco
18.
Lancet Psychiatry ; 6(7): 570-572, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31230682
19.
Gen Comp Endocrinol ; 282: 113211, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31238075

RESUMO

Most groupers (genus Epinephelus) inhabiting tropical and subtropical waters exhibit lunar-related reproductive cycles. Their gametes develop synchronously toward and are released around the species-selected moon phase. Periodical changes in cues from the moon are likely used as zeitgeber, and the hypothalamic-pituitary-gonadal (HPG) axis may be activated after cues are perceived by the sensory organ and transduced as internal signals. The objective of this study was to examine weekly changes in mRNA expression profiles of gonadotropin-releasing hormones (gnrh1 and gnrh2) and the ß-subunit of gonadotropins (fshß and lhß) during the spawning season (May to June) of the female honeycomb grouper Epinephelus merra, which spawns around the full moon period. When mature females were collected based on the lunar cycle, the gonadosomatic index peaked around the full moon. Ovarian histology revealed that oocytes laden with yolk developed toward the full moon and, subsequently, ovulatory follicles appeared around the last quarter moon, confirming lunar-related spawning with a full moon preference. Real-time quantitative polymerase chain reaction analyses revealed high abundances of fshß and lhß toward the first quarter moon, whereas concentrations of gnrh1 and gnrh2 increased around the last quarter moon and the first quarter moon, respectively, suggesting that transcription levels of these hormones fluctuate with the lunar cycle. The measurement of melatonin in the eye around the new moon and the full moon revealed that the ocular melatonin content was higher around the new moon than around the full moon, suggesting that the honeycomb grouper can perceive changes in moonlight. In addition, implantation of an osmotic pump containing melatonin into the body cavity of E. merra reduced the transcription levels of gonadotropins, suggesting that melatonin negatively affects hormonal synthesis at the HPG axis. We concluded that melatonin plays an essential role in transducing periodical changes in moonlight and that decreases in melatonin levels from the new moon to the full moon activate the HPG axis for entrainment of gonadal development and spawning.


Assuntos
Bass/fisiologia , Melatonina/farmacologia , Lua , Reprodução/fisiologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Olho/efeitos dos fármacos , Olho/metabolismo , Feminino , Hormônio Foliculoestimulante/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Hormônio Luteinizante/metabolismo , Oócitos/citologia , Oócitos/efeitos dos fármacos , Oócitos/metabolismo , Ovário/citologia , Ovário/efeitos dos fármacos , Ovário/metabolismo , Reprodução/efeitos dos fármacos , Estações do Ano
20.
J Fish Biol ; 95(3): 833-846, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31233213

RESUMO

The influence of the lunar cycle on the feeding habits, feeding success and selectivity was tested in situ on larval stages of the clingfish Gobiesox marmoratus (Gobiesocidae). Gobiesox marmoratus larvae and their prey were collected in the water column during the lunar cycle in austral spring 2015 and 2016, in shallow waters (<30 m depth) of El Quisco, central Chile. Feeding incidence was high (80-100%) throughout the moon cycle. The diet was composed of 32 prey items, being gastropod larvae and invertebrate eggs the most important. Prey composition varied among lunar phases with the lowest prey richness during new moon. During 2016, G. marmoratus larvae ingested the lowest number, but the largest prey during new moon. In spring 2015, there were no significant changes in the abundance of each prey taxon in the water column among moon phases, but in spring 2016 there were significant differences in the abundance of cypris and copepod nauplii, particularly between full and new moon. Feeding selectivity index showed that gastropod larvae were positively selected throughout the lunar cycle during spring 2015. In spring 2016, invertebrate eggs were selectively ingested in full moon and third quarter, but at a new moon G. marmoratus larvae selected gastropod larvae. Mean temperature of the water column and its vertical gradient and nocturnal cloud cover influences the feeding success of larval G. marmoratus. Lunar illumination favoured only an increase of richness of prey items. Therefore, nocturnal cloud cover precludes a greater influence of lunar illumination in the larval trophic ecology of this crypto-benthic fish.


Assuntos
Comportamento Alimentar/fisiologia , Peixes/fisiologia , Lua , Estações do Ano , Animais , Chile , Copépodes , Dieta , Gastrópodes , Larva , Fatores de Tempo
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