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Schiferl J, Kingston M, Åkesson CM, Valencia BG, Rozas-Davila A, McGee D, Woods A, Chen CY, Hatfield RG, Rodbell DT, Abbott MB, Bush MB. A neotropical perspective on the uniqueness of the Holocene among interglacials. Nat Commun 2023; 14:7404. [PMID: 37973878 PMCID: PMC10654573 DOI: 10.1038/s41467-023-43231-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 11/03/2023] [Indexed: 11/19/2023] Open
Abstract
Understanding how tropical systems have responded to large-scale climate change, such as glacial-interglacial oscillations, and how human impacts have altered those responses is key to current and future ecology. A sedimentary record recovered from Lake Junín, in the Peruvian Andes (4085 m elevation) spans the last 670,000 years and represents the longest continuous and empirically-dated record of tropical vegetation change to date. Spanning seven glacial-interglacial oscillations, fossil pollen and charcoal recovered from the core showed the general dominance of grasslands, although during the warmest times some Andean forest trees grew above their modern limits near the lake. Fire was very rare until the last 12,000 years, when humans were in the landscape. Here we show that, due to human activity, our present interglacial, the Holocene, has a distinctive vegetation composition and ecological trajectory compared with six previous interglacials. Our data reinforce the view that modern vegetation assemblages of high Andean grasslands and the presence of a defined tree line are aspects of a human-modified landscape.
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Affiliation(s)
- J Schiferl
- Institute for Global Ecology, Florida Institute of Technology, Melbourne, FL, 32901, USA
| | - M Kingston
- Institute for Global Ecology, Florida Institute of Technology, Melbourne, FL, 32901, USA
| | - C M Åkesson
- Institute for Global Ecology, Florida Institute of Technology, Melbourne, FL, 32901, USA
| | - B G Valencia
- Facultad de Ciencias de La Tierra y Agua, Universidad Regional Amazónica Ikiam, Tena, Ecuador
| | - A Rozas-Davila
- Institute for Global Ecology, Florida Institute of Technology, Melbourne, FL, 32901, USA
| | - D McGee
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - A Woods
- Department of Geology and Environmental Science, University of Pittsburgh, Pittsburgh, PA, USA
| | - C Y Chen
- Chemical and Isotopic Signatures Group, Nuclear and Chemical Sciences Division, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA
| | - R G Hatfield
- Department of Geological Sciences, University of Florida, Gainesville, FL, 32611, USA
| | - D T Rodbell
- Geoscience Department, Union College, Schenectady, NY, 12308, USA
| | - M B Abbott
- Department of Geology and Environmental Science, University of Pittsburgh, Pittsburgh, PA, USA
| | - M B Bush
- Institute for Global Ecology, Florida Institute of Technology, Melbourne, FL, 32901, USA.
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Bush MB, Rozas-Davila A, Raczka M, Nascimento M, Valencia B, Sales RK, McMichael CNH, Gosling WD. A palaeoecological perspective on the transformation of the tropical Andes by early human activity. Philos Trans R Soc Lond B Biol Sci 2022; 377:20200497. [PMID: 35249394 PMCID: PMC8899620 DOI: 10.1098/rstb.2020.0497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Palaeoecological records suggest that humans have been in the Andes since at least 14 000 years ago. Early human impacts on Andean ecosystems included an increase in fire activity and the extinction of the Pleistocene megafauna. These changes in Andean ecosystems coincided with rapid climate change as species were migrating upslope in response to deglacial warming. Microrefugia probably played a vital role in the speed and genetic composition of that migration. The period from ca 14 500 to 12 500 years ago was when novel combinations of plant species appeared to form no-analogue assemblages in the Andes. By 12 000 years ago most areas in what are today the Andean grasslands were being burned and modified by human activity. As the vegetation of these highland settings has been modified by human activity for the entirety of the Holocene, they should be regarded as long-term manufactutred landscapes. The sharp tree lines separating Andean forests from grasslands that we see today were probably also created by repeated burning and owe their position more to human-induced fire than climatic constraints. In areas that were readly penetrated by humans on the forested slopes of the Andes, substantial modification and settlement had occurred by the mid-Holocene. In hard-to-reach areas, however, the amount of human modification may always have been minimal, and these slopes can be considered as being close to natural in their vegetation. This article is part of the theme issue 'Tropical forests in the deep human past'.
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Affiliation(s)
- M B Bush
- Institute for Global Ecology, Florida Institute of Technology, Melbourne, FL 32901, USA
| | - A Rozas-Davila
- Institute for Global Ecology, Florida Institute of Technology, Melbourne, FL 32901, USA
| | - M Raczka
- Department of Geography and Environmental Science, University of Reading, Whiteknights, Reading, Berkshire RG6 6AH, UK
| | - M Nascimento
- Department of Ecosystem and Landscape Dynamics, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, 904 Science Park, 1098 XH, Amsterdam, Netherlands
| | - B Valencia
- Facultad de Ciencias de la Tierra y Agua, Ciencias de la Tierra y Clima, Universidad Regional Amazónica Ikiam, Tena, Ecuador
| | - R K Sales
- Institute for Global Ecology, Florida Institute of Technology, Melbourne, FL 32901, USA
| | - C N H McMichael
- Department of Ecosystem and Landscape Dynamics, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, 904 Science Park, 1098 XH, Amsterdam, Netherlands
| | - W D Gosling
- Department of Ecosystem and Landscape Dynamics, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, 904 Science Park, 1098 XH, Amsterdam, Netherlands
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Bush MB, Nascimento MN, Åkesson CM, Cárdenes-Sandí GM, Maezumi SY, Behling H, Correa-Metrio A, Church W, Huisman SN, Kelly T, Mayle FE, McMichael CNH. Widespread reforestation before European influence on Amazonia. Science 2021; 372:484-487. [PMID: 33926948 DOI: 10.1126/science.abf3870] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 03/29/2021] [Indexed: 01/19/2023]
Abstract
An estimated 90 to 95% of Indigenous people in Amazonia died after European contact. This population collapse is postulated to have caused decreases in atmospheric carbon dioxide concentrations at around 1610 CE, as a result of a wave of land abandonment in the wake of disease, slavery, and warfare, whereby the attendant reversion to forest substantially increased terrestrial carbon sequestration. On the basis of 39 Amazonian fossil pollen records, we show that there was no synchronous reforestation event associated with such an atmospheric carbon dioxide response after European arrival in Amazonia. Instead, we find that, at most sites, land abandonment and forest regrowth began about 300 to 600 years before European arrival. Pre-European pandemics, social strife, or environmental change may have contributed to these early site abandonments and ecological shifts.
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Affiliation(s)
- M B Bush
- Institute for Global Ecology, Florida Institute of Technology, Melbourne, FL, USA.
| | - M N Nascimento
- Institute for Global Ecology, Florida Institute of Technology, Melbourne, FL, USA.,Department of Ecosystem and Landscape Dynamics, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, Netherlands
| | - C M Åkesson
- Institute for Global Ecology, Florida Institute of Technology, Melbourne, FL, USA
| | - G M Cárdenes-Sandí
- Escuela Centroamericana de Geología, University of Costa Rica, San José, Costa Rica
| | - S Y Maezumi
- Department of Ecosystem and Landscape Dynamics, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, Netherlands
| | - H Behling
- Department of Palynology and Climate Dynamics, University of Goettingen, Goettingen, Germany
| | - A Correa-Metrio
- Instituto de Geología, Universidad Nacional Autónoma de México, Ciudad de México, México
| | - W Church
- Department of Earth and Space Sciences, Columbus State University, Columbus, GA, USA
| | - S N Huisman
- Department of Ecosystem and Landscape Dynamics, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, Netherlands
| | - T Kelly
- School of Geography, Queen Mary University of London, Mile End, London, UK
| | - F E Mayle
- Department of Geography and Environmental Science, University of Reading, Whiteknights, Reading, Berkshire, UK
| | - C N H McMichael
- Department of Ecosystem and Landscape Dynamics, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, Netherlands.
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Martínez C, Jaramillo C, Correa-Metrío A, Crepet W, Moreno JE, Aliaga A, Moreno F, Ibañez-Mejia M, Bush MB. Neogene precipitation, vegetation, and elevation history of the Central Andean Plateau. Sci Adv 2020; 6:eaaz4724. [PMID: 32923618 PMCID: PMC7455194 DOI: 10.1126/sciadv.aaz4724] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Accepted: 07/14/2020] [Indexed: 05/26/2023]
Abstract
Andean uplift played a fundamental role in shaping South American climate and species distribution, but the relationship between the rise of the Andes, plant composition, and local climatic evolution is poorly known. We investigated the fossil record (pollen, leaves, and wood) from the Neogene of the Central Andean Plateau and documented the earliest evidence of a puna-like ecosystem in the Pliocene and a montane ecosystem without modern analogs in the Miocene. In contrast to regional climate model simulations, our climate inferences based on fossil data suggest wetter than modern precipitation conditions during the Pliocene, when the area was near modern elevations, and even wetter conditions during the Miocene, when the cordillera was around ~1700 meters above sea level. Our empirical data highlight the importance of the plant fossil record in studying past, present, and future climates and underscore the dynamic nature of high elevation ecosystems.
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Affiliation(s)
- C. Martínez
- Plant Biology Section, School of Integrative Plant Sciences, Cornell University, 412 Mann Library Building, Ithaca, NY 14853, USA
- Smithsonian Tropical Research Institute, Unit 0948, APO AA 34002, Balboa, Ancon 084303092, Panama
| | - C. Jaramillo
- Smithsonian Tropical Research Institute, Unit 0948, APO AA 34002, Balboa, Ancon 084303092, Panama
- ISEM, U. Montpellier, CNRS, EPHE, IRD, Montpellier, France
| | - A. Correa-Metrío
- Instituto de Geología, Universidad Nacional Autónoma de México, Ciudad de México 04520, México
| | - W. Crepet
- Plant Biology Section, School of Integrative Plant Sciences, Cornell University, 412 Mann Library Building, Ithaca, NY 14853, USA
| | - J. E. Moreno
- Smithsonian Tropical Research Institute, Unit 0948, APO AA 34002, Balboa, Ancon 084303092, Panama
| | - A. Aliaga
- Departamento de Paleontología de Vertebrados, Museo de Historia Natural LimaUNMSM, Av. Arenales 1256, Jesús María, Lima, Perú
| | - F. Moreno
- Earth and Environmental Sciences, University of Rochester, 227 Hutchison Hall, University of Rochester, Rochester, NY 14627, USA
| | - M. Ibañez-Mejia
- Earth and Environmental Sciences, University of Rochester, 227 Hutchison Hall, University of Rochester, Rochester, NY 14627, USA
| | - M. B. Bush
- Ocean Engineering and Marine Sciences, Florida Institute of Technology, 225 Harris Building, Melbourne, FL, 32901, USA
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Palace MW, McMichael CNH, Braswell BH, Hagen SC, Bush MB, Neves E, Tamanaha E, Herrick C, Frolking S. Ancient Amazonian populations left lasting impacts on forest structure. Ecosphere 2017. [DOI: 10.1002/ecs2.2035] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Affiliation(s)
- M. W. Palace
- Earth Systems Research Center; Institute for the Study of Earth, Oceans and Space; University of New Hampshire; Durham New Hampshire 03834 USA
- Department of Earth Science; College of Engineering and Physical Sciences; University of New Hampshire; Durham New Hampshire 03834 USA
| | - C. N. H. McMichael
- Department of Ecosystem and Landscape Dynamics; Institute for Biodiversity and Ecosystem Dynamics; University of Amsterdam; 904 Science Park 1098XH Amsterdam The Netherlands
| | - B. H. Braswell
- Earth Systems Research Center; Institute for the Study of Earth, Oceans and Space; University of New Hampshire; Durham New Hampshire 03834 USA
- Applied GeoSolutions; 55 Main Street, Suite 125 Newmarket New Hampshire 03857 USA
| | - S. C. Hagen
- Applied GeoSolutions; 55 Main Street, Suite 125 Newmarket New Hampshire 03857 USA
| | - M. B. Bush
- Department of Biological Sciences; Florida Institute of Technology; 150 W. University Boulevard Melbourne Florida 32901 USA
| | - E. Neves
- Museu de Arqueologia e Etnologia; Universidade de São Paulo; Av. Prof. Almeida Prado, 1466 Sao Paulo Sao Paulo 05508-070 Brazil
| | - E. Tamanaha
- Laboratório de Arqueologia; Instituto de Desenvolvimento Sustentável Mamirauá; Estrada do Bexiga, 2.584, Bairro Fonte Boa Tefé Amazonas 69553-225 Brazil
| | - C. Herrick
- Earth Systems Research Center; Institute for the Study of Earth, Oceans and Space; University of New Hampshire; Durham New Hampshire 03834 USA
| | - S. Frolking
- Earth Systems Research Center; Institute for the Study of Earth, Oceans and Space; University of New Hampshire; Durham New Hampshire 03834 USA
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McMichael CH, Piperno DR, Bush MB. Comment on Clement et al. 2015 'The domestication of Amazonia before European conquest'. Proc Biol Sci 2016; 282:20151837. [PMID: 26702039 DOI: 10.1098/rspb.2015.1837] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- C H McMichael
- Palaeoecology and Landscape Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
| | - D R Piperno
- Smithsonian Tropical Research Institute, Balboa, Panama Department of Anthropology, National Museum of Natural History Smithsonian Institution, Washington, DC, USA
| | - M B Bush
- Department of Biological Sciences, Florida Institute of Technology, Melbourne, FL, USA
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Bush MB, Liedl B, Wagenlehner F, Yassouridis A, Petros PE. Effects of posture and squatting on the dynamics of micturition. Int Urogynecol J 2015; 26:779-80. [PMID: 25697465 DOI: 10.1007/s00192-015-2643-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Accepted: 01/27/2015] [Indexed: 10/24/2022]
Affiliation(s)
- M B Bush
- School of Mechanical and Chemical Engineering, The University of Western Australia, M050, 35 Stirling Hwy, Crawley, WA, 6081, Australia,
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McMichael CH, Palace MW, Bush MB, Braswell B, Hagen S, Neves EG, Silman MR, Tamanaha EK, Czarnecki C. Predicting pre-Columbian anthropogenic soils in Amazonia. Proc Biol Sci 2014; 281:20132475. [PMID: 24403329 DOI: 10.1098/rspb.2013.2475] [Citation(s) in RCA: 102] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The extent and intensity of pre-Columbian impacts on lowland Amazonia have remained uncertain and controversial. Various indicators can be used to gauge the impact of pre-Columbian societies, but the formation of nutrient-enriched terra preta soils has been widely accepted as an indication of long-term settlement and site fidelity. Using known and newly discovered terra preta sites and maximum entropy algorithms (Maxent), we determined the influence of regional environmental conditions on the likelihood that terra pretas would have been formed at any given location in lowland Amazonia. Terra pretas were most frequently found in central and eastern Amazonia along the lower courses of the major Amazonian rivers. Terrain, hydrologic and soil characteristics were more important predictors of terra preta distributions than climatic conditions. Our modelling efforts indicated that terra pretas are likely to be found throughout ca 154 063 km(2) or 3.2% of the forest. We also predict that terra preta formation was limited in most of western Amazonia. Model results suggested that the distribution of terra preta was highly predictable based on environmental parameters. We provided targets for future archaeological surveys under the vast forest canopy and also highlighted how few of the long-term forest inventory sites in Amazonia are able to capture the effects of historical disturbance.
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Affiliation(s)
- C H McMichael
- Earth Systems Research Center, University of New Hampshire, , Durham, NH 03824, USA, Department of Biological Sciences, Florida Institute of Technology, , Melbourne, FL 32901, USA, Applied Geosolutions, , Durham, NH 03824, USA, Laboratório de Arqueologia dos Trópicos, Museu de Arqueologia e Etnologia, Universidade de São Paulo, , São Paulo, Brazil, Department of Biology and Center for Energy, Environment and Sustainability, Wake Forest University, , Winston-Salem, NC 27106, USA
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McMichael CH, Piperno DR, Bush MB, Silman MR, Zimmerman AR, Raczka MF, Lobato LC. Sparse Pre-Columbian Human Habitation in Western Amazonia. Science 2012; 336:1429-31. [DOI: 10.1126/science.1219982] [Citation(s) in RCA: 158] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Bush MB, Silman MR, McMichael C, Saatchi S. Fire, climate change and biodiversity in Amazonia: a Late-Holocene perspective. Philos Trans R Soc Lond B Biol Sci 2008; 363:1795-02. [PMID: 18267914 PMCID: PMC2373879 DOI: 10.1098/rstb.2007.0014] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Fire is an important and arguably unnatural component of many wet Amazonian and Andean forest systems. Soil charcoal has been used to infer widespread human use of landscapes prior to European Conquest. An analysis of Amazonian soil carbon records reveals that the records have distinct spatial and temporal patterns, suggesting that either fires were only set in moderately seasonal areas of Amazonia or that strongly seasonal and aseasonal areas are undersampled. Synthesizing data from 300 charcoal records, an age–frequency diagram reveals peaks of fire apparently coinciding with some periods of very strong El Niño activity. However, the El Niño record does not always provide an accurate prediction of fire timing, and a better match is found in the record of insolation minima. After the time of European contact, fires became much scarcer within Amazonia. In both the Amazonia and the Andes, modern fire pattern is strongly allied to human activity. On the flank of the Andes, forests that have never burned are being eroded by fire spreading downslope from grasslands. Species of these same forests are being forced to migrate upslope due to warming and will encounter a firm artificial fire boundary of human activity.
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Affiliation(s)
- M B Bush
- Department of Biological Sciences, Florida Institute of Technology, 150 West University Boulevard, Melbourne, FL 32901, USA.
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Abstract
A prototype compression elastometer suited to the characterisation of soft tissue is analysed and tested by application to various elastomers. The test material is pinched between two rigid cylinders and the compression force and displacement interpreted to yield a measure of "effective" stiffness or to calibrate a simple non-linear-elastic material model (Neo-Hookean). This deformation suits the testing of bulk soft tissue since it effectively isolates the test material from boundary conditions such as other soft tissue, ligaments and bones. These can be highly variable in the body and can affect results greatly when employing other types of tests to determine the elastic nature of tissue. A simple linear-material analysis, based on established solutions to two-dimensional problems, is extended to take into account various geometrical complexities. This analysis permits immediate inversion of the readings from the device to yield the elastic properties of the material, without the need for complex numerical analysis. Finite element analysis is also employed to determine the range of reliable application of the linear-elastic model. In particular, this analysis permits the extension of the linear-elastic analysis to include simple forms of non-linear-material behaviour. The method is demonstrated using three elastomers having significantly different material properties. A viable range of application of the device is identified in which it yields results with reasonable precision and accuracy. The prototype device was able to measure the effective elastic modulus of the test materials with a maximum error of 13% for three material types (N=25). Repeatability error was less than 7% in all cases. Further refinement of the device and measuring system will reduce this uncertainty.
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Affiliation(s)
- S M Harrison
- School of Mechanical Engineering, The University of Western Australia, Crawley, WA 6009, Australia
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Whittaker RJ, Schmitt SF, Jones SH, Partomihardjo T, Bush MB. Stand Biomass and Tree Mortality from Permanent Forest Plots on Krakatau, Indonesia, 1989-19951. Biotropica 1998. [DOI: 10.1111/j.1744-7429.1998.tb00092.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
Our objective was to analyze the factors contributing to the development of detrusor pressure during micturition in the female with reference to a mathematical model. One hundred patients with predominantly stress incontinence were investigated with micturition pressure studies. Frictional and dynamic losses were estimated at various flow rates using a mathematical model. Almost 25% of patients recorded a micturition pressure below 11 cmH2O at peak flow (mean 23 cmH2O, range 0-91). Large inter- and intrapatient variations in micturition pressures were recorded on retesting. The low pressures were explained by a recently described external opening mechanism, backward stretching of the vagina during micturition by the muscles of the pelvic floor. This opened out the outflow tract and created the potential for a falsely high P(abd). The large variability in micturition pressures on retesting was attributed to changes in urethral radius being magnified to the fourth power. It was concluded that, micturition itself, and the components for pressure generation, are complex non-linear entities which appear to be greatly modified by the external striated pelvic floor opening mechanism. Addressing anatomical defects in this mechanism may be a fruitful route of future enquiry in females with emptying problems.
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Abstract
The flow characteristic for a human female urethra is determined by direct measurement of flow rate and pressure difference data. The measurements are made on a full-scale physical model of a urethra in its open state, which was created using dimensional information taken from video cystograms. The measured data therefore include viscous dissipation effects associated with developing flow, changes in cross-sectional area and changes in flow direction. These effects are often ignored in mathematical models of this system. The data may therefore assist in the development and testing of more realistic models for urine flow. The measured characteristic is compared with a mathematical model of the flow based on a straight tube of uniform diameter carrying fully developed turbulent flow. When the diameter of the model tube is chosen to be equal to the distal diameter of the urethra, it is observed that the predicted flow characteristic provides a good first approximation to the measured characteristic, despite the substantial differences in geometry and flow regime between the mathematical model and the actual system.
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Affiliation(s)
- M B Bush
- Department of Mechanical and Materials Engineering, University of Western Australia, Nedlands, Australia
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Colinvaux PA, De Oliveira PE, Moreno JE, Miller MC, Bush MB. A Long Pollen Record from Lowland Amazonia: Forest and Cooling in Glacial Times. Science 1996. [DOI: 10.1126/science.274.5284.85] [Citation(s) in RCA: 619] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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