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For managers of captive populations it is important to know whether their management provides a species with the physical and social environment that maximizes its survivorship. To determine this, survivorship comparisons with wild populations and long‐term evaluations of captive populations are important. Here we provide both for orangutans. We show that survivorship has increased during the past 60 years for captive orangutan populations in zoos. In addition, we show that survivorship of captive orangutans in the past used to be lower than for wild orangutans, but that for recently born (1986–2005) orangutans survivorship is not significantly different from the wild. This indicates that captive management in the past was suboptimal for orangutan survivorship, but that modern management of captive orangutans has increased their survivorship. We discuss the possible factors of modern management that could have influenced this. Am. J. Primatol. 71:680–686, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
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Twelve testable hypotheses on the geobiology of weathering 总被引:1,自引:0,他引:1
Brantley SL Megonigal JP Scatena FN Balogh-Brunstad Z Barnes RT Bruns MA Van Cappellen P Dontsova K Hartnett HE Hartshorn AS Heimsath A Herndon E Jin L Keller CK Leake JR McDowell WH Meinzer FC Mozdzer TJ Petsch S Pett-Ridge J Pregitzer KS Raymond PA Riebe CS Shumaker K Sutton-Grier A Walter R Yoo K 《Geobiology》2011,9(2):140-165
Critical Zone (CZ) research investigates the chemical, physical, and biological processes that modulate the Earth's surface. Here, we advance 12 hypotheses that must be tested to improve our understanding of the CZ: (1) Solar-to-chemical conversion of energy by plants regulates flows of carbon, water, and nutrients through plant-microbe soil networks, thereby controlling the location and extent of biological weathering. (2) Biological stoichiometry drives changes in mineral stoichiometry and distribution through weathering. (3) On landscapes experiencing little erosion, biology drives weathering during initial succession, whereas weathering drives biology over the long term. (4) In eroding landscapes, weathering-front advance at depth is coupled to surface denudation via biotic processes. (5) Biology shapes the topography of the Critical Zone. (6) The impact of climate forcing on denudation rates in natural systems can be predicted from models incorporating biogeochemical reaction rates and geomorphological transport laws. (7) Rising global temperatures will increase carbon losses from the Critical Zone. (8) Rising atmospheric P(CO2) will increase rates and extents of mineral weathering in soils. (9) Riverine solute fluxes will respond to changes in climate primarily due to changes in water fluxes and secondarily through changes in biologically mediated weathering. (10) Land use change will impact Critical Zone processes and exports more than climate change. (11) In many severely altered settings, restoration of hydrological processes is possible in decades or less, whereas restoration of biodiversity and biogeochemical processes requires longer timescales. (12) Biogeochemical properties impart thresholds or tipping points beyond which rapid and irreversible losses of ecosystem health, function, and services can occur. 相似文献
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Helfand BT Mendez MG Murthy SN Shumaker DK Grin B Mahammad S Aebi U Wedig T Wu YI Hahn KM Inagaki M Herrmann H Goldman RD 《Molecular biology of the cell》2011,22(8):1274-1289
Vimentin intermediate filaments (VIF) extend throughout the rear and perinuclear regions of migrating fibroblasts, but only nonfilamentous vimentin particles are present in lamellipodial regions. In contrast, VIF networks extend to the entire cell periphery in serum-starved or nonmotile fibroblasts. Upon serum addition or activation of Rac1, VIF are rapidly phosphorylated at Ser-38, a p21-activated kinase phosphorylation site. This phosphorylation of vimentin is coincident with VIF disassembly at and retraction from the cell surface where lamellipodia form. Furthermore, local induction of photoactivatable Rac1 or the microinjection of a vimentin mimetic peptide (2B2) disassemble VIF at sites where lamellipodia subsequently form. When vimentin organization is disrupted by a dominant-negative mutant or by silencing, there is a loss of polarity, as evidenced by the formation of lamellipodia encircling the entire cell, as well as reduced cell motility. These findings demonstrate an antagonistic relationship between VIF and the formation of lamellipodia. 相似文献
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Serge A. Wich Karyl B. Swartz Madeleine E. Hardus Adriano R. Lameira Erin Stromberg Robert W. Shumaker 《Primates; journal of primatology》2009,50(1):56-64
The capacity of nonhuman primates to actively modify the acoustic structure of existing sounds or vocalizations in their repertoire
appears limited. Several studies have reported population or community differences in the acoustical structure of nonhuman
primate long distance calls and have suggested vocal learning as a mechanism for explaining such variation. In addition, recent
studies on great apes have indicated that there are repertoire differences between populations. Some populations have sounds
in their repertoire that others have not. These differences have also been suggested to be the result of vocal learning. On
yet another level great apes can, after extensive human training, also learn some species atypical vocalizations. Here we
show a new aspect of great ape vocal learning by providing data that an orangutan has spontaneously (without any training)
acquired a human whistle and can modulate the duration and number of whistles to copy a human model. This might indicate that
the learning capacities of great apes in the auditory domain might be more flexible than hitherto assumed.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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Laura H. Coker Mark A. Espeland Stephen R. Rapp Claudine Legault Susan M. Resnick Patricia Hogan Sarah Gaussoin Maggie Dailey Sally A. Shumaker 《The Journal of steroid biochemistry and molecular biology》2010,118(4-5):304-310
This review discusses major findings from the Women's Health Initiative Memory Study (WHIMS). WHIMS reported hormone therapy (HT) – conjugated equine estrogen (CEE) with or without medroxyprogesterone acetate (MPA) – increased the risk for dementia (HR 1.76 [95% CI, 1.19–2.60]; P = 0.005) and global cognitive decline, with a mean decrement relative to placebo of 0.21 points on the Modified Mini Mental State Examination (3MS) (P = 0.006) in women age 65 and older.A subset of WHIMS participants joined the ancillary WHI Study of Cognitive Aging (WHISCA) trials, in which domain-specific cognitive tests and mood were measured annually. Compared with placebo, CEE + MPA had a negative impact on verbal memory over time (P = 0.01); and CEE-Alone was associated with lower spatial rotational ability (P ≤ 0.01) at the initial assessment, but the difference diminished over time.The ancillary WHIMS-MRI study measured subclinical cerebrovascular disease to possibly explain the negative cognitive findings reported by WHIMS and the increased clinical stroke in older women reported by the WHI. WHIMS-MRI reported that while CEE + MPA and CEE-Alone were not associated with increased ischemic brain lesion volume relative to placebo; both CEE + MPA and CEE-Alone were associated with lower mean brain volumes in the hippocampus (P = 0.05); frontal lobe (P = 0.004); and total brain (P = 0.07). HT-associated reductions in hippocampal volumes were greatest in women with baseline 3MS scores ≤90. 相似文献
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Adriano R. Lameira Madeleine E. Hardus Adrian M. Bartlett Robert W. Shumaker Serge A. Wich Steph B. J. Menken 《PloS one》2015,10(1)
The evolutionary origins of speech remain obscure. Recently, it was proposed that speech derived from monkey facial signals which exhibit a speech-like rhythm of ∼5 open-close lip cycles per second. In monkeys, these signals may also be vocalized, offering a plausible evolutionary stepping stone towards speech. Three essential predictions remain, however, to be tested to assess this hypothesis'' validity; (i) Great apes, our closest relatives, should likewise produce 5Hz-rhythm signals, (ii) speech-like rhythm should involve calls articulatorily similar to consonants and vowels given that speech rhythm is the direct product of stringing together these two basic elements, and (iii) speech-like rhythm should be experience-based. Via cinematic analyses we demonstrate that an ex-entertainment orangutan produces two calls at a speech-like rhythm, coined “clicks” and “faux-speech.” Like voiceless consonants, clicks required no vocal fold action, but did involve independent manoeuvring over lips and tongue. In parallel to vowels, faux-speech showed harmonic and formant modulations, implying vocal fold and supralaryngeal action. This rhythm was several times faster than orangutan chewing rates, as observed in monkeys and humans. Critically, this rhythm was seven-fold faster, and contextually distinct, than any other known rhythmic calls described to date in the largest database of the orangutan repertoire ever assembled. The first two predictions advanced by this study are validated and, based on parsimony and exclusion of potential alternative explanations, initial support is given to the third prediction. Irrespectively of the putative origins of these calls and underlying mechanisms, our findings demonstrate irrevocably that great apes are not respiratorily, articulatorilly, or neurologically constrained for the production of consonant- and vowel-like calls at speech rhythm. Orangutan clicks and faux-speech confirm the importance of rhythmic speech antecedents within the primate lineage, and highlight potential articulatory homologies between great ape calls and human consonants and vowels. 相似文献
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Herman Pontzer Mary H. Brown Brian M. Wood David A. Raichlen Audax.Z.P. Mabulla Jacob A. Harris Holly Dunsworth Brian Hare Kara Walker Amy Luke Lara R. Dugas Dale Schoeller Jacob Plange-Rhule Pascal Bovet Terrence E. Forrester Melissa Emery Thompson Robert W. Shumaker Jessica M. Rothman Stephen R. Ross 《Current biology : CB》2021,31(8):1804-1810.e5
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J M Shumaker J J Tollet K J Filbin M P Montague-Smith M C Pirrung 《Bioorganic & medicinal chemistry》2001,9(9):2269-2278
Detection of mutations in disease genes will be a significant application of genomic research. Methods for detecting mutations at the single nucleotide level are required in highly mutated genes such as the tumor suppressor p53. Resequencing of an individual patient's DNA by conventional Sanger methods is impractical, calling for novel methods for sequence analysis. Toward this end, an arrayed primer extension (APEX) method for identifying sequence alterations in primary DNA structure was developed. A two-dimensional array of immobilized primers (DNA chip) was fabricated to scan p53 exon 7 by single bases. Primers were immobilized with 200 microm spacing on a glass support. Oligonucleotide templates of length 72 were used to study individual APEX resequencing reactions. A template-dependent DNA polymerase extension was performed on the chip using fluorescein-labeled dideoxynucleotides (ddNTPs). Labeled primers were evanescently excited and the induced fluorescence was imaged by CCD. The average signal-to-noise ratio (S/N) observed was 30:1. Software was developed to analyze high-density DNA chips for sequence alterations. Deletion, insertion, and substitution mutations were detected. APEX can be used to scan for any mutation (up to two-base insertions) in a known region of DNA by fabricating a DNA chip comprising complementary primers addressing each nucleotide in the wild-type sequence. Since APEX is a parallel method for determining DNA sequence, the time required to assay a region is independent of its length. APEX has a high level of accuracy, is sequence-based, and can be miniaturized to analyze a large DNA region with minimal reagents. 相似文献