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961.
962.
The locomotion of Babakotia radofilai inferred from epiphyseal and diaphyseal morphology of the humerus and femur
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Damiano Marchi Christopher B. Ruff Alessio Capobianco Katherine L. Rafferty Michael B. Habib Biren A. Patel 《Journal of morphology》2016,277(9):1199-1218
Palaeopropithecids, or “sloth lemurs,” are a diverse clade of large‐bodied Malagasy subfossil primates characterized by their inferred suspensory positional behavior. The most recently discovered genus of the palaeopropithecids is Babakotia, and it has been described as more arboreal than Mesopropithecus, but less than Palaeopropithecus. In this article, the within‐bone and between‐bones articular and cross‐sectional diaphyseal proportions of the humerus and femur of Babakotia were compared to extant lemurs, Mesopropithecus and Palaeopropithecus in order to further understand its arboreal adaptations. Additionally, a sample of apes and sloths (Choloepus and Bradypus) are included as functional outgroups composed of suspensory adapted primates and non‐primates. Results show that Babakotia and Mesopropithecus both have high humeral/femoral shaft strength proportions, similar to extant great apes and sloths and indicative of forelimb suspensory behavior, with Babakotia more extreme in this regard. All three subfossil taxa have relatively large femoral heads, also associated with suspension in modern taxa. However, Babakotia and Mesopropithecus (but not Palaeopropithecus) have relatively small femoral head surface area to shaft strength proportions suggesting that hind‐limb positioning in these taxa during climbing and other behaviors was different than in extant great apes, involving less mobility. Knee and humeral articular dimensions relative to shaft strengths are small in Babakotia and Mesopropithecus, similar to those found in modern sloths and divergent from those in extant great apes and lemurs, suggesting more sloth‐like use of these joints during locomotion. Mesopropithecus and Babakotia are more similar to Choloepus in humerofemoral head and length proportions while Palaeopropithecus is more similar to Bradypus. These results provide further evidence of the suspensory adaptations of Babakotia and further highlight similarities to both extant suspensory primates and non‐primate slow arboreal climbers and hangers. J. Morphol. 277:1199–1218, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
963.
Katherine Tepperman Glenn Morris Francine Essien Stuart M. Heywood 《Journal of cellular physiology》1975,86(3):561-565
A cell preparation method by which large numbers of embryonic chick skeletal muscle cells may be obtained is described. The procedure requires fewer manipulations and much less time than standard trypsinization. By the criteria used, both methods are comparable with respect to percent viable cells and survival of plated cells. However, in addition to the ease of preparation, the mechanical dissociation method offers the significant advantage that the cell suspension is greatly enriched for myoblasts without the necessity of an additional preplating step. 相似文献
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965.
966.
Spatial management tools, such as marine spatial planning and marine protected areas, are playing an increasingly important role in attempts to improve marine management and accommodate conflicting needs. Robust data are needed to inform decisions among different planning options, and early inclusion of stakeholder involvement is widely regarded as vital for success. One of the biggest stakeholder groups, and the most likely to be adversely impacted by spatial restrictions, is the fishing community. In order to take their priorities into account, planners need to understand spatial variation in their perceived value of the sea. Here a readily accessible, novel method for quantitatively mapping fishers’ spatial access priorities is presented. Spatial access priority mapping, or SAPM, uses only basic functions of standard spreadsheet and GIS software. Unlike the use of remote-sensing data, SAPM actively engages fishers in participatory mapping, documenting rather than inferring their priorities. By so doing, SAPM also facilitates the gathering of other useful data, such as local ecological knowledge. The method was tested and validated in Northern Ireland, where over 100 fishers participated in a semi-structured questionnaire and mapping exercise. The response rate was excellent, 97%, demonstrating fishers’ willingness to be involved. The resultant maps are easily accessible and instantly informative, providing a very clear visual indication of which areas are most important for the fishers. The maps also provide quantitative data, which can be used to analyse the relative impact of different management options on the fishing industry and can be incorporated into planning software, such as MARXAN, to ensure that conservation goals can be met at minimum negative impact to the industry. This research shows how spatial access priority mapping can facilitate the early engagement of fishers and the ready incorporation of their priorities into the decision-making process in a transparent, quantitative way. 相似文献
967.
Isobel J. Whitehouse J. Scott Miners Elizabeth B. C. Glennon Patrick G. Kehoe Seth Love Katherine A. B. Kellett Nigel M. Hooper 《PloS one》2013,8(4)
The cellular prion protein (PrPC) has been implicated in the development of Alzheimer''s disease (AD). PrPC decreases amyloid-β (Aβ) production, which is involved in AD pathogenesis, by inhibiting β-secretase (BACE1) activity. Contactin 5 (CNTN5) has also been implicated in the development of AD by a genome-wide association study. Here we measured PrPC and CNTN5 in frontal cortex samples from 24 sporadic AD and 24 age-matched control brains and correlated the expression of these proteins with markers of AD. PrPC was decreased in sporadic AD compared to controls (by 49%, p = 0.014) but there was no difference in CNTN5 between sporadic AD and controls (p = 0.217). PrPC significantly inversely correlated with BACE1 activity (rs = −0.358, p = 0.006), Aβ load (rs = −0.456, p = 0.001), soluble Aβ (rs = −0.283, p = 0.026) and insoluble Aβ (rs = −0.353, p = 0.007) and PrPC also significantly inversely correlated with the stage of disease, as indicated by Braak tangle stage (rs = −0.377, p = 0.007). CNTN5 did not correlate with Aβ load (rs = 0.040, p = 0.393), soluble Aβ (rs = 0.113, p = 0.223) or insoluble Aβ (rs = 0.169, p = 0.125). PrPC was also measured in frontal cortex samples from 9 Down''s syndrome (DS) and 8 age-matched control brains. In contrast to sporadic AD, there was no difference in PrPC in the DS brains compared to controls (p = 0.625). These data are consistent with a role for PrPC in regulating Aβ production and indicate that brain PrPC level may be important in influencing the onset and progression of sporadic AD. 相似文献
968.
Edith K. MacRae Katherine B. Pryzwansky Marjorie H. Cooney John K. Spitznagel 《Cell and tissue research》1980,209(1):65-70
Summary Changes in surface morphology, as observed by scanning electron microscopy, appear rapidly when human polymorphonuclear neutrophils (PMN) are challenged with bacteria. Monolayers of PMN adhering to glass were incubated with opsonized E. coli from 5 sec to 10 min, and then fixed and prepared for SEM. As early as 5 sec after phagocytic challenge, E. coli are found in contact with PMN and in the process of engulfment into open cavities formed by lamellipodia. The shape of the mouth of the forming phagocytic vacuole is related to the orientation of bacteria during entry. Bacteria engulfed into early forming phagosomes are surrounded by a large open space between the bacteria and the phagosome wall. As phagocytosis proceeds, the space is reduced and the loose fit around the entering bacteria becomes tight. By 30 sec, bacteria may be completely internalized and by 1 min phagocytized E. coli are packed into bulging PMN. The observations reveal the variability and rapidity of the phagocytic response and confirm the presence of sensitive mechanisms for host defense by PMN.This work was supported by research grants from the University of North Carolina Research Council and the National Institutes of Health (A1 02430) 相似文献
969.
Trapido-Rosenthal Henry G.; Sharp Katherine H.; Galloway Tamara S.; Morrall Clare E. 《Integrative and comparative biology》2001,41(2):247-257
The presence of nitric oxide synthase (NOS) activity is demonstratedin the tropical marine cnidarian Aiptasia pallida and in itssymbiotic dinoflagellate algae, Symbiodinium bermudense. Enzymeactivity was assayed by measuring the conversion of arginineto citrulline. Biochemical characterization of NOS from Aiptasiawas characterized with respect to cellular localization, substrateand cofactor requirements, inhibitors, and kinetics. In responseto acute temperature shock, anemones retracted their tentacles.Animals subjected to such stress had lower NOS activities thandid controls. Treatment with NOS inhibitors caused tentacularretraction, while treatment with the NOS substrate L-arginineinhibited this response to stress, as did treatment with NOdonors. These results provide a preliminary biochemical characterizationof, and suggest a functional significance for, NOS activityin anthozoan-algal symbiotic assemblages. 相似文献
970.