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1.
Effects of paternal care on reproductive success in the polygynous spotless starling Sturnus unicolor 总被引:2,自引:0,他引:2
J. Moreno José P. Veiga Pedro J. Cordero Eduardo Mínguez 《Behavioral ecology and sociobiology》1999,47(1-2):47-53
For males of socially polygynous avian species like the spotless starling, there may exist a trade-off between investing in
paternal care and controlling several nests. To determine how the intensity of paternal care affects reproductive success
per brood sired or expressed as the total number of young raised in all nests controlled by the same male, it is necessary
to manipulate paternal care. Testosterone (T) has been shown to depress the tendency for males to care for their young, and
induces them to acquire more mates. The effects of paternal care on reproductive success were studied by treating certain
male starlings with exogenous T and others with the antiandrogen cyproterone acetate (CA), and comparing the parental behavior
of T- and CA-males throughout the breeding season with that of controls. CA-males fed their chicks more during the first week
after hatching than T-males, with controls feeding at intermediate rates, both on a per nest basis and as total effort for
all nests controlled by the same male. Paternal feeding rates during the first week of chick life had a significant positive
effect on the number of fledged young. The hormone treatment significantly affected the number of chicks raised per nest,
CA-males having a higher breeding success per nest than T-males, and controls showing intermediate levels of success. There
was no significant effect of treatment on total reproductive success attained by males throughout the season. In the polygonous
spotless starling, the intensity of paternal care of young affects reproductive success per nest positively but not on a seasonal
basis.
Received: 6 February 1999 / Received in revised form: 30 June 1999 / Accepted: 11 July 1999 相似文献
2.
Emotional,physical, and social needs among 0–5‐year‐old children displaced by the 2010 Chilean earthquake: associated characteristics and exposures 下载免费PDF全文
MaryCatherine Arbour Kara A. Murray Hirokazu Yoshikawa Felipe Arriet Cecilia Moraga Miguel Angel Cordero Vega 《Disasters》2017,41(2):365-387
An 8.8‐magnitude earthquake occurred off the coast of Chile on 27 February 2010, displacing nearly 2,000 children aged less than five years to emergency housing camps. Nine months later, this study assessed the needs of 140 displaced 0–5‐year‐old children in six domains: caregiver stability and protection; health; housing; nutrition; psychosocial situation; and stimulation. Multivariate regression was applied to examine the degree to which emotional, physical, and social needs were associated with baseline characteristics and exposure to the earthquake, to stressful events, and to ongoing risks in the proximal post‐earthquake context. In each domain, 20 per cent or fewer children had unmet needs. Of all children in the sample, 20 per cent had unmet needs in multiple domains. Children's emotional, physical, and social needs were associated with ongoing exposures amenable to intervention, more than with baseline characteristics or epicentre proximity. Relief efforts should address multiple interrelated domains of child well‐being and ongoing risks in post‐disaster settings. 相似文献
3.
Current brief aims to introduce the concept of safety in European industrial sectors, particularly in mechanics and machinery industry. It also highlights the importance to ensure an even level of machinery safety along the European Union, setting up the appropriate frame and procedures to keep it under control. An overview over market surveillance activities for machinery (regulations, main actors and their roles) first at Community level, and secondly an approach to one of the Member States is also introduced. 相似文献
4.
Reuel M. Bennett Paul Rodrigo F. Cordero Gershon S. Bautista 《Chemistry and Ecology》2013,29(4):320-328
The reductive adsorption of hexavalent chromium (Cr6+) using six indigenous microorganisms isolated from contaminated soil and water samples was investigated. Quantification of Cr6+ reduction was determined using the 1,5-diphenylcarbazide method followed measuring the absorbance at OD540. Bacterial isolates identified as Klebsiella pneumoniae, Bacillus firmus and Mycobacterium sp. were capable of absorbing Cr6+ efficiently into their biomass, whereas the fungal isolates, Aspergillus flavus, Aspergillus sp. and A. niger were capable of transforming Cr6+ to Cr3+ relative to cell-wall-binding properties. Infrared spectral analysis of functional groups showed that ?OH, ?NH2 and C?O with conjugated ?NH were the binding groups responsible for adsorption of Cr6+ within the biomass of isolates. The data highlight the promising biotechnological application of these isolates in removing carcinogenic and mutagenic Cr6+ from contaminated ecosystems. 相似文献
5.
Orellana FA Alegre JM Cordero Pérez JC Martín Redondo MP Delgado Huertas A Fernández Sampedro MT Menor-Salván C Ruiz-Bermejo M López-Vera F Rodríguez-Losada JA Martinez-Frias J 《Journal of environmental monitoring : JEM》2008,10(4):570-574
Certain local atmospheric anomalies, such as the formation of unusually large ice conglomerations (megacryometeors), have been proposed to be a potential natural hazard for people and aviation, as well as geoindicators for fingerprinting larger-scale atmospheric environmental changes. On March 13th 2007, at approximately 10:15 am, an ice chunk weighing about 10 kg fell from the clear-sky and crashed through the roof (around 15 m) of an industrial storage house in Mejorada del Campo, a town located 20 km east from Madrid. The megacryometeor monitoring follow-up and the original investigation presented here includes, for the first time, both logistic and scientific collaboration between the Laboratory of the Environment, Criminalistic Service (SECRIM, the Spanish "Guardia Civil") and academic and scientific institutions (universities and the Spanish National Research Council). We propose that the management procedure of the incident, along with the detailed scientific research and combination of analytical methodologies in different laboratories, can serve as a protocol model for other similar events. 相似文献
6.
P. J. Cordero S. C. Griffith J. M. Aparicio D. T. Parkin 《Behavioral ecology and sociobiology》2000,48(5):353-357
Recent evidence has revealed an apparently high degree of control by female birds over the physiological aspects of their
reproduction and offspring sex allocation, consistent with adaptive hypotheses of sex allocation and differential investment
in their offspring. In the house sparrow, we investigated possible mechanisms that may be used by females to enhance the fitness
returns from a reproductive effort. Using molecular techniques, we demonstrate that house sparrow eggs containing male embryos
are significantly larger than those containing female embryos. We also found that male embryos were laid randomly with respect
to laying order. We speculate that this sexual dimorphism of eggs is adaptive, because male house sparrows show greater variance
in condition-dependent reproductive success than females. More important, the result provides further evidence of the ability
of females to detect or control ovulation of either male or female ova and to differentially invest in one sex over the other.
Received: 19 January 2000 / Revised: 29 June 2000 / Accepted 20 July 2000 相似文献
7.
This article aims to highlight the current status of compliance to Machinery Directive 98/37/EC (transposed to Spanish regulation as RD 56/1995, of 20th January) (a new directive numbered as 2006/42/EC [Directive 2006/42/EC of the European Parliament and of the Council of 17 may 2006 on machinery, and amending Directive 95/16/EC (recast). OJ L157/24-86, 9.6.2006.], that recasts and replaced 98/37/ED directive and its amendments, came into force on 29 June 2006; it will not be applied until 29th December 2009. European Member States have a lead-time of two years to adopt and publish the national laws and regulations transposing the provisions of the new Directive into national law. Latest 10th October, Spain transposed Machinery Directive 2006/42/EC to national regulation as Real Decreto 1644/2008 [Real Decreto 1644/2008, de 10 de octubre, por el que se establecen las normas para la comercialización y puesta en servicio de las máquinas. BOE 246/2008, de 11 octubre 2008. Páginas 40995–41030]) of a particular family of machinery (hand-held, medium and small-size, deeply introduced in the market, of low-medium cost), that any user, professional or non-professional, can acquire as first-hand in any of the sales points (whether or not experts in these kind of products).At the same time, it emphasises the most significant shortcomings and non-conformities found, after analyzing the results of five consecutive Campaigns of Control of Industrial Products performed by one of the labs (placed in Spain) involved in the market surveillance European Program. 相似文献
8.
Carlos E. Rodr′?guez-Rodr′?guez Evelyn Rodr′?guez Rigoberto Blanco Ivannia Cordero Daniel Segura 《环境科学学报(英文版)》2010,22(10):1595-1601
Because of the lack of reports, the base levels of microbial contamination on stored fuels are unknown in tropical regions and it is
unclear whether these levels have some influence on fuel quality parameters. Therefore, fungal quality in automobile fuels stored across
Costa Rican territory was evaluated during two years according to the standard ASTM D6974-04. For a total of 96 samples, counts and
identification of molds and yeasts were performed on regular gas, premium gas and diesel taken from the bottom and superior part of
the container tanks. The highest contamination was found on the bottom of the tanks, where an aqueous phase was usually identified,
showing populations over the ones present in the hydrocarbon itself (up to 108 CFU/L). Diesel was the most contaminated fuel (up to
107 CFU/L); however, an alteration on the physicochemical parameters was not observed in any kind of fuel. Seventy-five mold strains
were isolated, Penicillium sp. being the most common genus (45.8% of the samples), and ten yeast strains, from the genera Candida sp.
and Rhodotorula sp. Four of the yeasts were able to grow on diesel as the sole carbon source, at concentrations ranging from 0.5% to
25%. Increasing the frequency of tank cleaning, adding antimicrobial agents and monitoring microbial populations are recommended
strategies to improve microbial quality of stored fuels. 相似文献
9.
C. Cordero 《Behavioral ecology and sociobiology》2000,48(6):458-462
The differential costs of mating paid by males and females influence the nature and strength of sexual selection. In butterflies,
males invest a relatively large amount of time and resources in each mating, but male survival costs of mating have not been
demonstrated. I present the results of experiments designed to measure the effect of different aspects of mating on male longevity
in the polygynous butterfly Callophrys xami. In experiment 1, I compared the longevity of pairs of males that produced similar amounts of spermatophore, but that mated
at different rates, a different numbers of times, and that produced spermatophores at different rates, and found that the
longevity of ”low-mating-rate” males was not different from that of ”high-mating-rate” males. In experiment 2, the longevity
of virgin males was not significantly different from that of multiply mated males. In experiment 3, I used resource-limited
males resulting from experimental food limitation of last-instar larvae; resource-limited virgin males lived significantly
more days than resource-limited multiply mated males. Since ecological costs of mating (e.g., disease transmission, predation
risk) were excluded in the experiment, diminished male longevity was a product of physiological costs of sexual interactions.
These results suggest that the cost of ejaculate production is an important cause of longevity reduction when there are resource
limitations; however, the role of other possible physiological costs of mating in longevity reduction is still unknown.
Received: 21 March 2000 / Accepted: 26 August 2000 相似文献
10.