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Middle phalangeal hair was found to be present in 71% if Saudi Arabian males. For those exhibiting this trait, the frequency of combinations of digits with hair was similar to the frequency in other populations. 相似文献
4.
Nichola J. K. Hole Edmundo Lamoyi Masanori Komatsu Nagaradona Harindranath Glendowlyn O. Young-Cooper Rose G. Mage 《Immunogenetics》1988,28(2):99-107
In order to investigate linkage, we used serum allotypes of the two rabbit C
isotypes and restriction fragment length polymorphisms (RFLPs) of the genes for V
, C
, and T-cell receptor C
. The inheritance of these genetic markers was studied through backcross and F2 matings. Southern analysis and hybridization of genomic DNA with a C probe detected a 5 kb Pst I fragment linked to expression of the K2bas1 allotype and the presence of the 1b
bas gene and a 6.6 kb Pst I fragment linked to the expression of the K1b9 allotype, the presence of the 2
bas2 gene and lack of expression of the K2bas1 allotype. A V probe detected a 1.3 kb Eco RI fragment linked to the presence of the 1b
bas gene and expression of the K2bas1 allotype. In contrast, the 9 or 14 kb Eco RI RFLP (C
a or C
b) detected with a Tcr
chain probe segregated independently from C allotypes and RFLPs. It has previously been found that C and C
are also unlinked in man, whereas in the mouse they are linked at a distance of 8 centimorgans. 相似文献
5.
Nichola A. Strandberg Mary Edwards Joanna C. Ellison Manuel J. Steinbauer Anna Walentowitz Patricia L. Fall David Sear Peter Langdon Shane Cronin Alvaro Castilla-Beltrán Ian W. Croudace Matiu Prebble William D. Gosling Sandra Nogué 《Biotropica》2023,55(4):816-827
Here, we investigate Mid- to Late-Holocene vegetation changes in low-lying coastal areas in Tonga and how changing sea levels and recurrent volcanic eruptions have influenced vegetation dynamics on four islands of the Tongan archipelago (South Pacific). To investigate past vegetation and environmental change at Ngofe Marsh (‘Uta Vava’u), we examined palynomorphs (pollen and spores), charcoal (fire), and sediment characteristics (volcanic activity) from a 6.7-m-long sediment core. Radiocarbon dating indicated the sediments were deposited over the last 7700 years. We integrated the Ngofe Marsh data with similar previously published data from Avai’o’vuna Swamp on Pangaimotu Island, Lotofoa Swamp on Foa Island, and Finemui Swamp on Ha’afeva Island. Plant taxa were categorized as littoral, mangrove, rainforest, successional/ disturbance, and wetland groups, and linear models were used to examine relationships between vegetation, relative sea level change, and volcanic eruptions (tephra). We found that relative sea level change has impacted vegetation on three of the four islands investigated. Volcanic eruptions were not identified as a driver of vegetation change. Rainforest decline does not appear to be driven by sea level changes or volcanic eruptions. From all sites analyzed, vegetation at Finemui Swamp was most sensitive to changes in relative sea level. While vegetation on low-lying Pacific islands is sensitive to changing sea levels, island characteristics, such as area and elevation, are also likely to be important factors that mediate specific island responses to drivers of change. 相似文献
6.
G.B. Picken 《Journal of experimental marine biology and ecology》1980,42(1):71-85
Twenty-one monthly collections of the Antarctic limpet Nacella (Patinigera) concinna (Strebel, 1908) were obtained by divers at Signy Island, South Orkney Islands. A mean monthly population density of 123.7 ± 21.2 · m?2, mean biomass of 13.7 ± 2.7 g dry tissue wt · m?2, and annual production of 2.9 g · m?2 were recorded in the depth range 2–12 m below mean low water.Shell growth was slow with a maximum growth rate, in the first 3–5 yr of life, of 3 4 mm per year. Maturity was attained at 7–8 yr (21 mm length), and maximum size (41 mm length) at about 21 yr. Unique spawning behaviour was observed in two Austral springs, and data relating spawning to the spring increase in sea temperature were obtained. 相似文献
7.
Paul Deutchman Mark Bračič Nichola Raihani Katherine McAuliffe 《Evolution and human behavior》2021,42(1):12-20
There are two broad functional explanations for second-party punishment: fitness-leveling and deterrence. The former suggests that people punish to reduce fitness differences, while the latter suggests that people punish in order to reciprocate losses and deter others from inflicting losses on them in the future. We explore the relative roles of these motivations using a pre-registered, two-player experiment with 2426 US participants from Amazon Mechanical Turk. Participants played as the “responder” and were assigned to either a Take or Augment condition. In the Take condition, the “partner” could steal money from the responder's bonus or do nothing. In the Augment condition, the partner could augment the responder's bonus by giving them money at no cost to themselves or do nothing. We also manipulated the responders' starting endowments, such that after the partner's decision, responders experienced different payoff outcomes: advantageous inequity, equality, or varying degrees of disadvantageous inequity. Responders then decided whether to pay a cost to punish the partner. Punishment was clearly influenced by theft and was most frequent when theft resulted in disadvantageous inequity. However, people also punished in the absence of theft, particularly when confronted with disadvantageous inequity. While the effect of inequity on punishment was small, our results suggest that punishment is motivated by more than just the desire to reciprocate losses. These findings highlight the multiple motivations undergirding punishment and bear directly on functional explanations for the existence of punishment in human societies. 相似文献
8.
Darren Boone Susan Mallett Shihua Zhu Guiqing Lily Yao Nichola Bell Alex Ghanouni Christian von Wagner Stuart A. Taylor Douglas G. Altman Richard Lilford Steve Halligan 《PloS one》2013,8(12)
Purpose
To establish the relative weighting given by patients and healthcare professionals to gains in diagnostic sensitivity versus loss of specificity when using CT colonography (CTC) for colorectal cancer screening.Materials and Methods
Following ethical approval and informed consent, 75 patients and 50 healthcare professionals undertook a discrete choice experiment in which they chose between “standard” CTC and “enhanced” CTC that raised diagnostic sensitivity 10% for either cancer or polyps in exchange for varying levels of specificity. We established the relative increase in false-positive diagnoses participants traded for an increase in true-positive diagnoses.Results
Data from 122 participants were analysed. There were 30 (25%) non-traders for the cancer scenario and 20 (16%) for the polyp scenario. For cancer, the 10% gain in sensitivity was traded up to a median 45% (IQR 25 to >85) drop in specificity, equating to 2250 (IQR 1250 to >4250) additional false-positives per additional true-positive cancer, at 0.2% prevalence. For polyps, the figure was 15% (IQR 7.5 to 55), equating to 6 (IQR 3 to 22) additional false-positives per additional true-positive polyp, at 25% prevalence. Tipping points were significantly higher for patients than professionals for both cancer (85 vs 25, p<0.001) and polyps (55 vs 15, p<0.001). Patients were willing to pay significantly more for increased sensitivity for cancer (p = 0.021).Conclusion
When screening for colorectal cancer, patients and professionals believe gains in true-positive diagnoses are worth much more than the negative consequences of a corresponding rise in false-positives. Evaluation of screening tests should account for this. 相似文献9.
Richardson Bryce Martin Holly Bartels-Hardege Helga Fletcher Nichola Hardege Jörg Detlef 《Aquatic Ecology》2022,56(2):409-418
Aquatic Ecology - Arguably climate change is one of the biggest challenges faced by many organisms. One of the more significant of these is the decreasing pH level of the ocean, a consequence of... 相似文献
10.
Lyme Disease in the US is concentrated in three endemic areas: the Northeast, the upper mid-West, and the Pacific coast. In the mid-West, the range of Lyme disease has expanded to include large parts of Wisconsin and Minnesota. Despite its proximity to the mid-Western focus, Illinois, so far, has not been considered an endemic area. However, more recent data suggest that this situation may be changing. Also, the extent of borrelial diversity in the mid-West remains largely unexplored. Here, we present preliminary results on the molecular characterization of Borrelia isolates from rodents captured in Cook and Lake Counties, both of which are parts of the greater metropolitan Chicago area in Illinois. We investigated the rodent reservoir present in forested areas of suburban Chicago in order to determine the frequency of infection with the Lyme disease agent(s) by culture isolation of Borrelia spirochetes (Picken et al., unpublished). Rodent isolates of Borrelia were identified to the species level by genetic characterization. In total, 19 isolates were obtained over 3 years from NW Cook Co. and Lake Co. Pulsed-field gel electrophoretic analysis of Mlul digested DNA from these isolates showed macrorestriction patterns similar to that of the Californian isolate, strain DN127 (PF type I), New York isolate strain 25015 (PF type II), or a variant of the latter (PF type III). Sequence data generated from the rrf(5S)-rrl(23S) intergenic spacer region of the ribosomal RNA gene cluster confirmed the identity of all the Chicago isolates studied to date as B. bissettii. These strains are unlike our previous Borrelia isolates from NW Illinois and Wisconsin. In addition, there was a predominant association of B. bissettii infection with pratal rodent species such as Microtus pennsylvanicus and Zapus hudsonius. The relationship of this novel enzootic focus to the established mid-Western endemic focus of Lyme disease remains to be elucidated. The geographic range and reservoir diversity of this organism may have hitherto been underestimated. 相似文献