19 research outputs found
High Proportion of Male Faeces in Jaguar Populations
Faeces provide relevant biological information which includes, with the application of genetic techniques, the sex and identity of individuals that defecated, thus providing potentially useful data on the behaviour and ecology of individuals, as well as the dynamics and structure of populations. This paper presents estimates of the sex ratio of different felid species (jaguar, Panthera onca; puma, Puma concolor; and ocelot/margay, Leopardus pardalis/Leopardus wiedi) as observed in field collected faeces, and proposes several hypotheses that could explain the strikingly high proportion of faeces from male jaguars. The proportion of male and female faeces was estimated using a non-invasive faecal sampling method in 14 study areas in Mexico and Brazil. Faecal samples were genetically analysed to identify the species, the sex and the individual (the latter only for samples identified as belonging to jaguars). Considering the three species, 72.6% of faeces (n = 493) were from males; however, there were significant differences among them, with the proportion from males being higher for jaguars than for pumas and ocelots/margays. A male-bias was consistently observed in all study areas for jaguar faeces, but not for the other species. For jaguars the trend was the same when considering the number of individuals identified (n = 68), with an average of 4.2±0.56 faeces per male and 2.0±0.36 per female. The observed faecal marking patterns might be related to the behaviour of female jaguars directed toward protecting litters from males, and in both male and female pumas, to prevent interspecific aggressions from male jaguars. The hypothesis that there are effectively more males than females in jaguar populations cannot be discarded, which could be due to the fact that females are territorial and males are not, or a tendency for males to disperse into suboptimal areas for the species. © 2012 Palomares et al
Multi-messenger observations of a binary neutron star merger
On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta
Family influence on the consumption of sugary drinks by children under two years old
OBJETIVO Avaliar a influência de hábitos familiares e características do domicílio sobre o consumo de bebidas açucaradas em crianças brasileiras menores de dois anos. MÉTODOS Estudo transversal que utilizou dados secundários gerados pela Pesquisa Nacional de Saúde (PNS), em 2013. Foram estudados 4.839 pares de crianças menores de dois anos e adultos residentes no mesmo domicílio. Foram estimadas as prevalências do indicador consumo de bebidas açucaradas para a amostra total de crianças e segundo categorias de variáveis familiares e do domicílio. Aplicou-se análise de regressão logística múltipla para avaliar a influência de hábitos familiares e características do domicílio sobre o consumo de bebidas açucaradas pelas crianças. RESULTADOS O consumo de bebidas açucaradas foi identificado em 32% das crianças estudadas (IC95% 30,6–33,3) e esteve independentemente associado com as seguintes caraterísticas familiares e domiciliares: consumo regular de bebidas açucaradas pelo adulto residente no domicílio (OR = 1,78; IC95% 1,51–2,10), hábito de assistir TV por mais de 3 horas diárias (OR = 1,22; IC95% 1,03–1,45), maior idade (OR = 3,10; IC95% 1,54–6,26), maior escolaridade (OR = 0,70; IC95% 0,53–0,91), domicílio localizado na região Nordeste (OR = 0,65; IC95% 1,54–6,26) e número de componentes da família (OR = 1,05; IC95% 1,00–1,09). CONCLUSÕES Os achados apontam a alta prevalência de consumo de bebidas açucaradas em crianças brasileiras menores de dois anos e que características sociodemográficas e hábitos familiares influenciam essa prática alimentar não recomendada na infância.OBJECTIVE To evaluate the influence of family habits and household characteristics on the consumption of sugary drinks by Brazilian children under two years old. METHODS This was a cross-sectional study that used secondary data generated by the National Health Survey (PNS) in 2013. We studied 4,839 pairs of children under two years old and adults living in the same house. We estimated the prevalence of the indicator of sugary drinks consumption for the total sample of children and according to family and household variables. We applied multiple logistic regression analysis to evaluate the influence of family habits and household characteristics on the consumption of sugary drinks by the children. RESULTS The consumption of sugary drinks was identified in 32% of the studied children (95%CI 30.6-33.3) and was independently associated with the following family and household characteristics: regular consumption of sugary drinks by the adult living in the house (OR = 1.78; 95%CI 1.51-2.10), watching TV for more than three hours per day (OR = 1.22; 95%CI 1.03-1.45), older age (OR = 3.10; 95%CI 1.54-6.26), greater education level (OR = 0.70; 95%CI 0.53-0.91), house located in the Northeast region (OR = 0.65; 95%CI 1.54-6.26), and number of family members (OR = 1.05; 95%CI 1.00-1.09). CONCLUSIONS Our findings indicate the high prevalence of sugary drinks consumption by Brazilian children under two years old and show that sociodemographic characteristics and family habits affect this feeding practice not recommended in childhood