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101.
Measuring the metabolic of sea turtles is fundamental to understanding their ecology yet the presently available methods are limited. Accelerometry is a relatively new technique for estimating metabolic rate that has shown promise with a number of species but its utility with air-breathing divers is not yet established. The present study undertakes laboratory experiments to investigate whether rate of oxygen uptake (
o
2) at the surface in active sub-adult green turtles Chelonia mydas and hatchling loggerhead turtles Caretta caretta correlates with overall dynamic body acceleration (ODBA), a derivative of acceleration used as a proxy for metabolic rate. Six green turtles (25–44 kg) and two loggerhead turtles (20 g) were instrumented with tri-axial acceleration logging devices and placed singly into a respirometry chamber. The green turtles were able to submerge freely within a 1.5 m deep tank and the loggerhead turtles were tethered in water 16 cm deep so that they swam at the surface. A significant prediction equation for mean
o
2 over an hour in a green turtle from measures of ODBA and mean flipper length (R2 = 0.56) returned a mean estimate error across turtles of 8.0%. The range of temperatures used in the green turtle experiments (22–30°C) had only a small effect on
o
2. A
o
2-ODBA equation for the loggerhead hatchling data was also significant (R2 = 0.67). Together these data indicate the potential of the accelerometry technique for estimating energy expenditure in sea turtles, which may have important applications in sea turtle diving ecology, and also in conservation such as assessing turtle survival times when trapped underwater in fishing nets. 相似文献
102.
103.
Julia S. Ampuero Víctor Oca?a Jorge Gómez María E. Gamero Josefina Garcia Eric S. Halsey V. Alberto Laguna-Torres 《PloS one》2012,7(10)
Background
Currently, there is a paucity of data regarding human adenovirus (HAdv) circulation in Andean regions of South America. To address this shortcoming, we report the clinical, phylogenetic, and epidemiologic characteristics of HAdv respiratory tract infection from a large sentinel surveillance study conducted among adults and children in Peru.Methods/Principal Findings
Oropharyngeal swabs were collected from participants visiting any of 38 participating health centers, and viral pathogens were identified by immunofluorescence assay in cell culture. In addition, molecular characterization was performed on 226 randomly selected HAdv samples. Between 2000 and 2010, a total of 26,375 participants with influenza-like illness (ILI) or severe acute respiratory infection (SARI) were enrolled in the study. HAdv infection was identified in 2.5% of cases and represented 6.2% of all viral pathogens. Co-infection with a heterologous virus was found in 15.5% of HAdv cases. HAdv infection was largely confined to children under the age of 15, representing 88.6% of HAdv cases identified. No clinical characteristics were found to significantly distinguish HAdv infection from other respiratory viruses. Geographically, HAdv infections were more common in sites from the arid coastal regions than in the jungle or highland regions. Co-circulation of subgroups B and C was observed each year between 2006 and 2010, but no clear seasonal patterns of transmission were detected.Conclusions/Significance
HAdv accounted for a significant fraction of those presenting with ILI and SARI in Peru and tended to affect the younger population disproportionately. Longitudinal studies will help better characterize the clinical course of patients with HAdv in Peru, as well as determine the role of co-infections in the evolution of illness. 相似文献104.
105.
Neal A. Halsey 《CMAJ》2008,179(6):509-510
106.
Lewis G. Halsey Steven J. Portugal Jennifer. A. Smith Campbell P. Murn Rory P. Wilson 《Journal of Field Ornithology》2009,80(2):171-177
ABSTRACT. Measuring body movements using accelerometry data loggers is a relatively new technique, the full applicability of which has yet to be tested on volant birds. Our study illustrates the potential of accelerometry for research on large birds by using the technique to record the behavior of three species of raptors, mainly during flight. A tri-axial accelerometer was deployed on a trained Harris' Hawk ( Parabuteo unicinctus ), Tawny Eagle ( Aquila rapax ), and Griffon Vulture ( Gyps fulvus ). Comparison of flight-related variables calculated from video footage and that estimated from the acceleration data showed that the latter provided considerable and accurate information (usually <10% error) about the behavior of the birds, including wing-beat frequency and when they glided and flapped. Acceleration data permitted tentative comparisons of relative movement-specific rates of energy expenditure for the Griffon Vulture flying up versus flying down a small hill. The accelerometry data appeared to suggest, as expected, that the Griffon Vulture expended more energy flying uphill than flying back down. Our preliminary findings indicate that studies using accelerometers can likely provide information about the detailed time–energy budgets of large birds. Such information would aid in comparative analyses of behavior and energetics, and may also enhance efforts to conserve declining bird populations. 相似文献
107.
Background
The leaf epidermis is an important architectural control element that influences the growth properties of underlying tissues and the overall form of the organ. In dicots, interdigitated pavement cells are the building blocks of the tissue, and their morphogenesis includes the assembly of specialized cell walls that surround the apical, basal, and lateral (anticlinal) cell surfaces. The microtubule and actin cytoskeletons are highly polarized along the cortex of the anticlinal wall; however, the relationships between these arrays and cell morphogenesis are unclear. 相似文献108.
Shah A S Rahim KH Bhatti A Khan N Din M Imran M Mohsin M Ishtiaq A Nabila A Ansari S Hussain M Zafar M Mushtaq E Mumtaz J Iqbal 《Phyton》2015,84(1):34-44
Sargodha district is one of the least studied regions of Pakistan regarding its ethnobotanical values. This paper is the first report related to the documentation and conservation status of the tree species in the Sargodha district, and their folk ethnobotanical uses. An interview base survey was conducted in the study area in 2010-2013. The ethnobotanical data revealed the use of 100 tree species (6 gymnosperms, 94 angiosperms) belonging to 77 genera (6 gymnosperms, 71 angiosperms) and 39 families (4 gymnosperms, 35 angiosperms), with the Fabaceae ranking first with 19 tree species, followed by the Moraceae (12 species). Tree species like Aegle marmelos, Butea monosperma, Diospyrus malabarica, Gmelina arborea, Kigelia africana, Manilkara hexandra, Manilkara zapota, Mimusops elengi, Nyctanthes arbor-tristis, Putranjiva roxburghii, Terminalia arjuna and Terminalia bellerica are not only unique in their medicinal value but also interesting because of their unusual occurrence here. Thevetia peruviana, Cassia fistula, Celtis australis, Delonix regia, Diospyrus malabarica, Grevillea robusta, Haplophragma adenophylum, Jacaranda mimosifolia, Lagerstroemia speciosa, Plumeria rubra, Pterospermum acerifolium, Roystonea regia, Taxodium distichum and Tectona grandis are included among the worth looking ornamental tree species. Capparis decidua, Dalbergia sissoo, Tamarix aphylla, Tamarix dioica, Prosopis cineraria and Ziziphus mauritiana are the most commonly used timber species. Other common ethnobotanical utilization of these trees includes either sheltering or fuel or agricultural uses. Lack of awareness about the potential uses of these species, and particularly ignorance of the concerned authorities, have led to a decline in the population of this precious tree flora. Documentation of this tree flora, and as-sociated indigenous knowledge, can be used as a basis for developing management plans for conservation and sustainable use of this flora in the study area. A well-organized management is critical to restore and conserve this endangered natural resource in the District Sargodha, Pakistan. The immense medicinal and timber value of these tree species make it necessary to promote their conservation to simultaneously alleviate the poverty and improve the socio-economic status of the study area. 相似文献
109.
Halsey LG Shepard EL Hulston CJ Venables MC White CR Jeukendrup AE Wilson RP 《Zoology (Jena, Germany)》2008,111(3):231-241
An important element in the measurement of energy budgets of free-living animals is the estimation of energy costs during locomotion. Using humans as a particularly tractable model species, we conducted treadmill experiments to test the validity of tri-axial accelerometry loggers, designed for use with animals in the field, to estimate rate of oxygen consumption (VO2: an indirect measure of metabolic rate) and speed during locomotion. The predictive power of overall dynamic body acceleration (ODBA) obtained from loggers attached to different parts of the body was compared to that of heart rate (fH). When subject identity was included in the statistical analysis, ODBA was a good, though slightly poorer, predictor of VO2 and speed during locomotion on the flat (mean of two-part regressions: R2=0.91 and 0.91, from a logger placed on the neck) and VO2 during gradient walking (single regression: R2=0.77 from a logger placed on the upper back) than was fH (R2=0.96, 0.94, 0.86, respectively). For locomotion on the flat, ODBA was still a good predictor when subject identity was replaced by subject mass and height (morphometrics typically obtainable from animals in the field; R2=0.92 and 0.89) and a slightly better overall predictor than fH (R2=0.92 and 0.85). For gradient walking, ODBA predicted VO2 more accurately than before (R2=0.83) and considerably better than did fH (R2=0.77). ODBA and fH combined were the most powerful predictor of VO2 and speed during locomotion. However, ODBA alone appears to be a good predictor and suitable for use in the field in particular, given that accelerometry traces also provide information on the timing, frequency and duration of locomotion events, and also the gait being used. 相似文献
110.
Tillieux SL Halsey WS Thomas ES Voycik JJ Sathe GM Vassilev V 《Journal of virology》2008,82(22):11023-11044
Varicella-zoster virus (VZV) is a herpesvirus and is the causative agent of chicken pox (varicella) and shingles (herpes zoster). Active immunization against varicella became possible with the development of live attenuated varicella vaccine. The Oka vaccine strain was isolated in Japan from a child who had typical varicella, and it was then attenuated by serial passages in cell culture. Several manufacturers have obtained this attenuated Oka strain and, following additional passages, have developed their own vaccine strains. Notably, the vaccines Varilrix and Varivax are produced by GlaxoSmithKline Biologicals and Merck & Co., Inc., respectively. Both vaccines have been well studied in terms of safety and immunogenicity. In this study, we report the complete nucleotide sequence of the Varilrix (Oka-VGSK) and Varivax (Oka-VMerck) vaccine strain genomes. Their genomes are composed of 124,821 and 124,815 bp, respectively. Full genome annotations covering the features of Oka-derived vaccine genomes have been established for the first time. Sequence analysis indicates 36 nucleotide differences between the two vaccine strains throughout the entire genome, among which only 14 are involved in unique amino acid substitutions. These results demonstrate that, although Oka-VGSK and Oka-VMerck vaccine strains are not identical, they are very similar, which supports the clinical data showing that both vaccines are well tolerated and elicit strong immune responses against varicella. 相似文献