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401.
Polidori A Arhami M Sioutas C Delfino RJ Allen R 《Journal of the Air & Waste Management Association (1995)》2007,57(3):366-379
Hourly indoor and outdoor fine particulate matter (PM2.5), organic and elemental carbon (OC and EC, respectively), particle number (PN), ozone (O3), carbon monoxide (CO), and nitrogen oxide (NOx) concentrations were measured at two different retirement communities in the Los Angeles, CA, area as part of the Cardiovascular Health and Air Pollution Study. Site A (group 1 [G1]) was operated from July 6 to August 20, 2005 (phase 1 [P1]) and from October 19 to December 10, 2005 (P2), whereas site B (group 2 [G2]) was operated from August 24 to October 15, 2005 (P1), and from January 4 to February 18, 2006 (P2). Overall, the magnitude of indoor and outdoor measurements was similar, probably because of the major influence of outdoor sources on indoor particle and gas levels. However, G2 showed a substantial increase in indoor OC, PN, and PM2.5 between 6:00 and 9:00 a.m., probably from cooking. The contributions of primary and secondary OC (SOA) to measured outdoor OC were estimated from collected OC and EC concentrations using EC as a tracer of primary combustion-generated OC (i.e., "EC tracer method"). The study average outdoor SOA accounted for 40% of outdoor particulate OC (40-45% in the summer and 32-40% in the winter). Air exchange rates (hr(-1)) and infiltration factors (Finf; dimensionless) at each site were also determined. Estimated Finf and measured particle concentrations were then used in a single compartment mass balance model to assess the contributions of indoor and/or outdoor sources to measured indoor OC, EC, PM2.5, and PN. The average percentage contributions of indoor SOA of outdoor origin to measured indoor OC were approximately 35% (during G1P1 and G1P2) and approximately 45% (for G2P1 and G2P2). On average, 36% (G2P1) to 44% (G1P1) of measured indoor OC was composed of outdoor-generated primary OC. 相似文献
402.
The results of this study provide a measure of the levels of dioxin-like compounds (polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and polychlorinated biphenyls) in pooled blood serum collected throughout Australia in 2003. De-identified samples selected from surplus pathology samples were stratified on the basis of gender, region and age. In total 9090 samples were collected and analysed as 96 pools. Dioxin-like chemicals were detected in all strata. The mean and median levels expressed as TEQ values for all pooled samples were 10.9+/-1.0 pg TEQ g(-1) lipid and 8.3 pg TEQ g(-1) lipid. For males and females the mean levels were 10.4+/-0.6 pg TEQ g(-1) lipid and 11.5+/-1.5 pg TEQ g(-1) lipid, respectively. A direct relationship of increasing dioxin-like chemical levels with increasing age was observed and could be described by the following equation: Levels in blood expressed as pg TEQ g(-1) lipid = 3.3 exp(0.0251 age) (r2 = 0.87). No significant differences were observed in the levels of dioxin-like chemicals in samples collected from males and females. In addition, the levels of dioxin-like chemicals across the five regions were similar within each age range. In summary, the levels of dioxin-like chemicals in the Australian population are low compared to international levels and are similar across all regions of Australia within each designated age range. The levels of these chemicals increase with age and can be estimated if the age of an individual is known. 相似文献
403.
404.
Lachlan G. Howell Peter R. Mawson Pierre Comizzoli Ryan R. Witt Richard Frankham Simon Clulow Justine K. O'Brien John Clulow Paul Marinari John C. Rodger 《Conservation biology》2023,37(2):e14010
Managed breeding programs are an important tool in marsupial conservation efforts but may be costly and have adverse genetic effects in unavoidably small captive colonies. Biobanking and assisted reproductive technologies (ARTs) could help overcome these challenges, but further demonstration of their potential is required to improve uptake. We used genetic and economic models to examine whether supplementing hypothetical captive populations of dibblers (Parantechinus apicalis) and numbats (Myrmecobius fasciatus) with biobanked founder sperm through ARTs could reduce inbreeding, lower required colony sizes, and reduce program costs. We also asked practitioners of the black-footed ferret (Mustela nigripes) captive recovery program to complete a questionnaire to examine the resources and model species research pathways required to develop an optimized biobanking protocol in the black-footed ferret. We used data from this questionnaire to devise similar costed research pathways for Australian marsupials. With biobanking and assisted reproduction, inbreeding was reduced on average by between 80% and 98%, colony sizes were on average 99% smaller, and program costs were 69- to 83-fold lower. Integrating biobanking made long-standing captive genetic retention targets possible in marsupials (90% source population heterozygosity for a minimum of 100 years) within realistic cost frameworks. Lessons from the use of biobanking technology that contributed to the recovery of the black-footed ferret include the importance of adequate research funding (US$4.2 million), extensive partnerships that provide access to facilities and equipment, colony animals, appropriate research model species, and professional and technical staff required to address knowledge gaps to deliver an optimized biobanking protocol. Applied research investment of A$133 million across marsupial research pathways could deliver biobanking protocols for 15 of Australia's most at-risk marsupial species and 7 model species. The technical expertise and ex situ facilities exist to emulate the success of the black-footed ferret recovery program in threatened marsupials using these research pathways. All that is needed now for significant and cost-effective conservation gains is greater investment by policy makers in marsupial ARTs. 相似文献
405.
Martin P Tims S McGill A Ryan B Pfitzner K 《Environmental monitoring and assessment》2006,115(1-3):531-554
This article describes an airborne γ survey of a 7 × 5 km region around the rehabilitated Nabarlek uranium mine in northern Australia. An unusually tight line spacing (100 m) and low aircraft height (50 m) were used, enabling the survey to distinguish man-made structures such as ponds and accommodation areas, as well as creek lines. Positive correlations between airborne data and ground-based readings enabled an estimation of the average absorbed dose rate arising from terrestrial γ radiation over large areas of the site to be derived. For the fenced minesite area this estimate was 0.31 μ Gy hr− 1. The airborne survey data were found to be invaluable in helping to plan further ground-level investigations and showed promise as an assessment tool for rehabilitated minesites. 相似文献
406.
M. Genevieve W. Jones N. M. S. Mareile Techow Peter G. Ryan 《Behavioral ecology and sociobiology》2012,66(9):1213-1224
Genetic techniques have revealed surprisingly high rates of extra-pair paternity (EPP) in socially monogamous albatrosses. We sought to establish social and genetic influences on EPP in wandering albatrosses (Diomedea exulans) at Marion Island, where EPP rates were 14–24?% in three successive seasons. EPP probably resulted from both female solicited extra-pair behaviours and male forced copulations. EPP was not linked to breeding experience nor with poor reproductive performance, despite a tendency for pairs to consistently produce either EPP or within-pair paternity (WPP) chicks. Mate guarding may inhibit extra-pair behaviour; however, parental arrival date and presence in the colony prior to laying did not correlate with EPP. There was little support for genetic advantages to producing EPP chicks, but the population is characterised by low genetic variability, which may result in mate incompatibility. Mates of pairs that failed and pairs producing EPP young tended to be more similar genetically to their partners than mates producing WPP young, suggesting that EPP may counter mate incompatibility. EPP and WPP chicks grow equally well, so cuckolded males did not reduce investment in EPP chicks. The lack of discriminatory behaviour by cuckolded males together with low genetic diversity in the population may allow continued high levels of EPP. In albatrosses, pair bonds are typically long lasting and the costs of forming new pairings may discourage mate swapping. Females may undertake extra-pair copulations as an adaptive alternative to mate swapping because the costs of extra-pair behaviour are small. 相似文献
407.
Ryan?R.?GermainEmail author Matthew?W.?Reudink Peter?P.?Marra Peter?T.?Boag Laurene?M.?Ratcliffe 《Behavioral ecology and sociobiology》2012,66(3):419-431
Many animals use multiple signals in sexual communication, but our understanding of the interactions between multiple signals,
particularly in inexperienced breeders, is limited. In birds, delayed plumage maturation (DPM) is well documented; young birds
appear duller than adults, despite reaching sexual maturity. Age-related changes in song structure are also common in songbirds,
though the extent to which songs of yearling males differ from those of adults (delayed song maturation, DSM) and its prevalence
in species with DPM is unknown. We tested for DSM in the mate-attraction (repeat) song of a species with dramatic DPM, the
American redstart (Setophaga ruticilla). Repeat song structure of territorial yearling and adult males differed significantly, based on discriminant analysis of
nine non-collinear song features. Combined with previous evidence of delayed maturation in territorial (serial) song, we provide
the first evidence for DSM in different song types used in different behavioral contexts during the breeding season of a migratory
songbird. Within adults, variation in repeat song was associated with pairing, earlier onset of breeding, and number of offspring
sired, suggesting a potential benefit for expressing more adult-like song. We found no relationship between the expression
of adult-like repeat song and plumage in either age class. These results indicate that delayed maturation of repeat song in
yearling redstarts is not due to a generalized delay in signal development, and suggest further work is needed to determine
whether mate attraction (for both yearling and adult males) provides greater pressure to sound more “adult-like” than to look
more “adult-like”. 相似文献
408.
Abstract: Forest isolation resulting from fragmentation is thought to impede the movement of forest songbirds. Because of the difficulty of tracking birds continuously, however, few data exist documenting the influence of isolation and landscape features on avian movements. During the breeding season, male Hooded Warblers ( Wilsonia citrina ) leave their small (<2.5 ha), isolated forest patches to travel between forest fragments. We documented a total of 106 forays ( n = 20 males) and found that individuals traveled up to 2.5 km away from their resident forest patch, primarily to solicit covert extra-pair copulations. Forays occurred despite the absence of forested corridors connecting fragments; even when corridors were present, males most often chose to fly directly across open fields. Resident patch size and distance to forests visited were not correlated with the frequency of forays. The maximum distance males flew over open fields did not exceed 465 m, and longer distances likely inhibit males from traveling outside their woodlots. If territorial establishment depends on the availability of extra-pair partners, then higher degrees of isolation between forests could explain why some species avoid settling in extremely fragmented landscapes. Conservation efforts should limit isolation between forest stands, thereby preserving the ability of animals to move within fragmented landscapes during the breeding season. 相似文献
409.
Despite the consensus that mate choice acts as a mechanism for selection of secondary sexual traits, the evolutionary forces affecting mate preferences themselves remain controversial. In this study, we first demonstrated selection acting directly on the mate preferences of monogamous male oldfield mice, Peromyscus polionotus rhoadsi. One group of male oldfield mice were allowed to express a social preference between two potential mates, and were subsequently paired with either their preferred or rejected female. Among these pairs, those containing preferred females produced more offspring than did those containing rejected females. We next demonstrated that this fitness advantage depended primarily on compatibility between the members of a mated pair. A second group of male oldfield mice were not allowed the opportunity to express a social preference between potential mates. Rather, these males were paired with females that had been either preferred or rejected by males in the first group. Among these pairs, those containing preferred females did not produce more offspring than those containing rejected females. In other words, individual mate preferences had fitness consequences only for those males that expressed them, demonstrating that these preferences were based primarily on compatibility between mates. 相似文献
410.
Ehrich Dorothée Schmidt Niels M. Gauthier Gilles Alisauskas Ray Angerbjörn Anders Clark Karin Ecke Frauke Eide Nina E. Framstad Erik Frandsen Jay Franke Alastair Gilg Olivier Giroux Marie-Andrée Henttonen Heikki Hörnfeldt Birger Ims Rolf A. Kataev Gennadiy D. Kharitonov Sergey P. Killengreen Siw T. Krebs Charles J. Lanctot Richard B. Lecomte Nicolas Menyushina Irina E. Morris Douglas W. Morrisson Guy Oksanen Lauri Oksanen Tarja Olofsson Johan Pokrovsky Ivan G. Popov Igor Yu. Reid Donald Roth James D. Saalfeld Sarah T. Samelius Gustaf Sittler Benoit Sleptsov Sergey M. Smith Paul A. Sokolov Aleksandr A. Sokolova Natalya A. Soloviev Mikhail Y. Solovyeva Diana V. 《Ambio》2020,49(3):801-804
Ambio - In the original published article, some of the symbols in figure 1A were modified incorrectly during the typesetting and publication process. The correct version of the figure is provided... 相似文献