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81.
TORGEIR NYGÅRD 《Ibis》1999,141(1):85-90
Eggshell thickness is often expressed by means of an index based on the length, breadth and weight of the shell. The effect of the blow-hole and egg eccentricity on Ratcliffe's shell thickness index was investigated in a sample of 585 eggs from six raptor species. Corrections for the size of the hole and egg eccentricity are proposed, as is a combined formula to correct both sources of error at the same time. It is shown that by using these formulae, considerable improvements in estimates of shell thinning are obtained. These may be especially useful when sample sizes are small, which is often the case when working with species that have been reduced in numbers. 相似文献
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84.
Ryan Schram 《The Australian journal of anthropology》2013,24(1):30-47
This article examines the relationship between Christian worship and the production of religious identity among Auhelawa speakers of Normanby Island, Papua New Guinea. Auhelawa people live in a society in which a locally developed form of Christianity has emerged from a long engagement with missionaries. In the colonial era, missionaries spoke in terms of light and darkness to mediate their contradictory aims of both authentic personal conversion and total social change. Today Auhelawa believe that their society has been changed, and that this change entails a new way of thinking as well as acting, though like the missionaries they also struggle to express the relationship between the two. Viewing themselves as already converted, Auhelawa today use an ideology of ‘one mind’—unity in purpose which is subjectively felt and outwardly expressed—to resolve how their collective worship relates to individual belief. This framing of ritual, embedded in church prayer and music, however, is always incomplete. I argue this not only points to an important step in the process of formation of congregations, but also suggests why Christianity globally is both unitary yet also so strikingly diverse. 相似文献
85.
Ryan Schram 《Ethnos》2013,78(4):447-470
There is a growing consensus that money and the market principle have not led to a great transformation into modernity. Rather, market exchange is everywhere socially embedded. But what does this embedding consist of, structural limits, tactics of resistance, or moral boundaries? Auhelawa (Normanby Island, Papua New Guinea) have incorporated money into their local economy in a variety of ways which keep the logic of the market in check. The comparison between two modes of accumulation – business and charity – sheds light on the precise nature of embeddedness. Local entrepreneurs describe themselves as navigating dilemmas which arise from contradictions between accumulation and reciprocity. Church congregations, however, appear to have transcended this conflict by representing their charitable contributions of money as love-gifts which are not subject to reciprocity. While charity, like business, is an embedded form of accumulation, I argue that it creates links to an alternative hierarchy of values, and thus contains the potential to create a great transformation of its own. 相似文献
86.
Microbially influenced corrosion (MIC) is being increasingly recognised as a serious problem. To investigate the role of MIC, radiotracer activity and lipid biomass measurements were performed on samples from offshore and on‐shore natural gas transmission systems. These measurements evaluated the biomass and metabolism of microbial communities residing inside transmission pipelines. Aqueous and nonaqueous hydrocarbon samples from liquid separators, sludge catchers and nodules attached to pipe walls were aseptically recovered and inoculated into anaerobic tubes for radiotracer time course experiments or preserved with chloroform‐methanol for total lipid analyses. MPN enrichments and phospholipid biomass determinations estimated microbial populations of 104—107 cells per gram in several samples. General microbial metabolism was demonstrated by [l‐14C]acetate incorporation into lipids and by [14C]CO2 production from [U‐14C]glucose. [14C]Acetate was slowly mineralised to 14CO2 without significant methane production. [14C]Acetate was produced by fermentation of [14C]glucose, [14C]palmitate and by hydrogen mediated acetogenesis in the presence of [I4C]CO2. In one location acetogenesis from hydrogen and carbon dioxide accounted for 0–7 mmol.l‐1 of acetate production per week. These results demonstrated that microorganisms could utilise natural gas impurities to produce organic acids. This activity could adversely affect the structural integrity (MIC) of high pressure natural gas pipelines. 相似文献
87.
Gus Koerbin Jillian R Tate Julie Ryan Graham RD Jones Ken A Sikaris David Kanowski Maxine Reed Janice Gill George Koumantakis Tina Yen Andrew St John Peter E Hickman Aaron Simpson Peter Graham 《The Clinical biochemist. Reviews / Australian Association of Clinical Biochemists》2014,35(4):203-211
Harmonisation of reference intervals for routine general chemistry analytes has been a goal for many years. Analytical bias may prevent this harmonisation. To determine if analytical bias is present when comparing methods, the use of commutable samples, or samples that have the same properties as the clinical samples routinely analysed, should be used as reference samples to eliminate the possibility of matrix effect. The use of commutable samples has improved the identification of unacceptable analytical performance in the Netherlands and Spain. The International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) has undertaken a pilot study using commutable samples in an attempt to determine not only country specific reference intervals but to make them comparable between countries. Australia and New Zealand, through the Australasian Association of Clinical Biochemists (AACB), have also undertaken an assessment of analytical bias using commutable samples and determined that of the 27 general chemistry analytes studied, 19 showed sufficiently small between method biases as to not prevent harmonisation of reference intervals. Application of evidence based approaches including the determination of analytical bias using commutable material is necessary when seeking to harmonise reference intervals. 相似文献
88.
Gregory S. Vosganian Jill Waalen Kevin Kim Sejal Jhatakia Ethan Schram Tracey Lee Dan Riddell James R. Mason 《Cytotherapy》2012,14(10):1228-1234
Background aimsThe long-term stability of cryopreserved peripheral blood progenitor cells is an important issue for patients experiencing disease relapse. However, there is no consensus on how to evaluate the long-term effects of cryopreservation. We describe the effect of cryopreservation on viability and progenitor colony activity from 87 individual samples processed at the Scripps Green Hospital Stem Cell Processing Center (La Jolla, CA, USA).MethodsWe randomly selected 87 peripheral blood hematopoietic stem cell (PBHSC) samples from 60 patients and evaluated the effect of cryopreservation on sample viability and red and white cell colony activity after < 24 h and 7, 10 and 15 years of cryopreservation. Viability was assayed via trypan blue dye exclusion and activity was measured following 14 days of culture.ResultsAn age at collection older than 50 years may result in suboptimal activity and viability following long-term cryopreservation, while gender and disease status had no effect. Cryopreservation did not significantly affect white or red cell activity following 10 years of cryopreservation. However, for samples stored longer than 10 years, viability and activity significantly decreased. We noted a positive association between higher pre-cryopreservation %CD34 count and colony activity.ConclusionsCryopreservation of peripheral blood progenitor cells for up to 10 years results in no loss of clonogenic capacity, as determined by culture activity, although longer durations of storage may affect activity. Until validated methods are developed, cryopreserved grafts should be evaluated based on pre-freeze CD34+ cell counts as assayed by flow cytometry, and post-thaw sample evaluation should be reserved for patients identified as poor mobilizers. 相似文献
89.
Terry L. Margenau Steven P. AveLallemant David Giehtbrock Stephen T. Schram 《Hydrobiologia》2008,601(1):111-123
Northern pike (pike) Esox lucius Linnaeus are broadly distributed across Wisconsin and provide an important sport fishery for anglers. Historical management
has included use of angling regulations, stocking, and protection of critical habitat areas. Pike management is often a lower
priority in comparison to more intensively managed species such as muskellunge Esox masquinongy Mitchell and walleye Sander vitreous. Pike provide angling opportunities year around, with higher catch rates and live release during open water, and higher harvest
rates during winter. While length of pike caught during the two seasons is generally similar, there is some evidence that
larger fish are caught during winter months. Results from minimum length limit changes implemented in 1995 have been equivocal
and warrant further monitoring using standardized protocol to better determine effects on populations. If natural recruitment
is not limited, pike populations can reach high densities and stunting can result. Loss of nearshore habitat has continued
at an increased rate as more lake homes are built and shorelines graded, and altered with riprap, sand blankets, or sea walls.
If natural recruitment is lacking, fry or fingerling stocking sustains or rehabilitates populations. Most pike stocking occurs
in the southeastern portion of the state where habitat loss has been extensive. Stocking in other areas is largely to re-establish
populations following a chemical reclamation or from winterkill. Future management needs to establish sampling protocols to
ensure comparable data on both a temporal and a spatial scale. Long-term monitoring with these methods is essential to help
determine effects of various factors (e.g., regulations, habitat loss) on populations.
Guest editors: J. M. Farrell, C. Skov, M. Mingelbier, T. Margenau & J. E. Cooper
International Pike Symposium: Merging Knowledge of Ecology, Biology, and Management for a Circumpolar Species 相似文献
90.
Vincent Schram 《生物化学与生物物理学报:生物膜》2003,1616(2):165-173
Two small hydrophobic proteins, SP-B and SP-C, are responsible for rapid adsorption of pulmonary surfactant to the air/water interface. Despite their physiological importance, the number of protein molecules required to trigger an absorption event remains unknown. To investigate this issue, we varied the protein content of calf lung surfactant extract (CLSE) by dilution with protein-depleted surfactant lipids (neutral and phospholipids, N&PL). Vesicles of a constant size and of composition ranging between 100% N&PL and 100% CLSE were generated by probe sonication. Their adsorption kinetics to an air/water interface were monitored at different temperatures using a Wilhelmy plate to measure surface tension. When plotted versus protein concentration, the adsorption rates during the initial change in surface tension exhibit a diphasic behavior, first increasing rapidly and linearly between 0% and 25% CLSE, and then more slowly at higher concentrations. Direct linearity at low protein content (0-5% CLSE ratio) was confirmed at 37 °C. These observations argue against cooperative behavior, for which the adsorption rate would first rise slowly with the protein content, and then increase suddenly once the critical number of proteins on each vesicle is reached. The apparent activation energy Ea and the free energy of activation ΔG0*, calculated from the temperature dependence of adsorption, further support the view that at least the early stages of protein-induced surfactant adsorption proceeds through a sequence of events involving not several, but a single surfactant protein. 相似文献