670 results on '"A. D. Muir"'
Search Results
52. Phylogenetic history of vascular plant metabolism revealed using a macroevolutionary common garden
- Author
-
Matthew W. Pennell, Christopher D. Muir, Barbara M. Neto-Bradley, and Jeannette Whitton
- Subjects
0106 biological sciences ,Vascular plant ,Evolution ,Acclimatization ,Macroevolution ,Photosynthesis ,010603 evolutionary biology ,01 natural sciences ,General Biochemistry, Genetics and Molecular Biology ,C3 photosynthesis ,Botany ,Botanical garden ,Plant metabolism ,Phylogeny ,General Environmental Science ,General Immunology and Microbiology ,biology ,Phylogenetic tree ,General Medicine ,Metabolism ,Carbon Dioxide ,biology.organism_classification ,Plant Leaves ,General Agricultural and Biological Sciences ,010606 plant biology & botany - Abstract
While the fundamental biophysics of C 3 photosynthesis is highly conserved across plants, substantial leaf structural and enzymatic variation translates into variability in rates of carbon assimilation. Although this variation is well documented, it remains poorly understood how photosynthetic rates evolve, and whether macroevolutionary changes are related to the evolution of leaf morphology and biochemistry. A substantial challenge in large-scale comparative studies is disentangling evolutionary adaptation from environmental acclimation. We overcome this by using a ‘macroevolutionary common garden’ approach in which we measured metabolic traits ( J max and V cmax ) from 111 phylogenetically diverse species in a shared environment. We find substantial phylogenetic signal in these traits at moderate phylogenetic timescales, but this signal dissipates quickly at deeper scales. Morphological traits exhibit phylogenetic signal over much deeper timescales, suggesting that these are less evolutionarily constrained than metabolic traits. Furthermore, while morphological and biochemical traits (LMA, N area and C area ) are weakly predictive of J max and V c max , evolutionary changes in these traits are mostly decoupled from changes in metabolic traits. This lack of tight evolutionary coupling implies that it may be incorrect to use changes in these functional traits in response to global change to infer that photosynthetic strategy is also evolving.
- Published
- 2021
53. Resident hill country pasture production in response to temperature and soil moisture over 20 years in Central Hawke’s Bay
- Author
-
Derrick J. Moot, Smith Nb, Beverley C. Thomson, Annamaria Mills, and P. D. Muir
- Subjects
geography ,geography.geographical_feature_category ,Animal science ,Moisture ,Spring (hydrology) ,Soil water ,Environmental science ,Dry matter ,Water-use efficiency ,Bay ,Water content ,Pasture - Abstract
The production of resident pastures on rolling hill country was measured in three paddocks over 20 years at Poukawa in Central Hawke’s Bay. The pastures had been routinely fertilised with 250 kg/ha/yr of superphosphate but no pasture renovation, nor nitrogen fertiliser application, occurred during the measurement period. Total annual dry matter (DM) yield ranged from 4.5 to 12.8 t/ha/yr, which shows the level of variability to be expected in this summer-dry environment. The greatest proportion (60-90%) of growth occurred in winter/spring with consistent mean growth rates of 50-62 kg DM/ha/d in September and October. These rates were calculated to be 5.49±0.55 kg DM/ha/°Cd when spring moisture was non-limiting. The pastures had a mean water use efficiency of 16.9±0.34 kg DM/ha/mm of water available (R2 = 0.93). The amount of water available was calculated from a soil water budget based on a plant available water holding capacity of 124 mm (0-1.0 m depth). The results provide coefficients that can be combined with readily available climate data to predict pasture growth rates for feed budgeting purposes. Rainfall data collected on-site was highly correlated (r=0.94) with that predicted from the NIWA virtual climate station network.
- Published
- 2021
- Full Text
- View/download PDF
54. Scaling between stomatal size and density in forest plants
- Author
-
Nianpeng He, Gang Yu, Chu-Xiao Liu, Mingrun Li, Lin Xu, Xingguo Han, de Boer Hj, Y. Li, Ju-Yuan Zhang, Lawren Sack, and Christopher D. Muir
- Subjects
Stomatal conductance ,Agronomy ,Carbon gain ,Covariance ,Photosynthesis ,Crop productivity ,Scaling ,Mathematics ,Stomatal density ,Maximum rate - Abstract
The size and density of stomatal pores limit the maximum rate of leaf carbon gain and water loss (gmax) in land plants. The limits of gmax due to anatomy, and its constraint by the negative correlation of stomatal size and density at broad phylogenetic scales, has been unclear and controversial. The prevailing hypothesis posits that adaptation to higher gmax is typically constrained by geometry and/or an economic need to reduce the allocation of epidermal area to stomata (stomatal-area minimization), and this would require the evolution of greater numbers of smaller stomata. Another view, supported by the data, is that across plant diversity, epidermal area allocated to guard cells versus other cells can be optimized without major trade-offs, and higher gmax would typically be achieved with a higher allocation of epidermal area to stomata (stomatal-area increase). We tested these hypotheses by comparing their predictions for the structure of the covariance of stomatal size and density across species, applying macroevolutionary models and phylogenetic regression to data for 2408 species of angiosperms, gymnosperms, and ferns from forests worldwide. The observed stomatal size-density scaling and covariance supported the stomatal-area increase hypothesis for high gmax. A higher gmax involves construction costs and maintenance costs that should be considered in models assessing optimal stomatal conductance for predictions of water use, photosynthesis, and water-use efficiency as influences on crop productivity or in Earth System models.
- Published
- 2021
- Full Text
- View/download PDF
55. Videoconferencing psychotherapy for couples and families: A systematic review
- Author
-
Samuel D Muir, Neil Thomas, Denny Meyer, S. S. M. Silva, Elizabeth Seabrook, Maja Nedeljkovic, and Kathleen de Boer
- Subjects
Family therapy ,Male ,050103 clinical psychology ,2019-20 coronavirus outbreak ,Psychotherapist ,Sociology and Political Science ,Social Psychology ,Coronavirus disease 2019 (COVID-19) ,Attitude of Health Personnel ,computer.software_genre ,Couples Therapy ,Videoconferencing ,Medicine ,Humans ,0501 psychology and cognitive sciences ,Telerehabilitation ,business.industry ,Remote Consultation ,05 social sciences ,COVID-19 ,Telemedicine ,Clinical Practice ,Physical Therapists ,Clinical Psychology ,050902 family studies ,Treatment delivery ,Treatment modality ,Family Therapy ,Female ,0509 other social sciences ,business ,computer ,Social Sciences (miscellaneous) ,Systematic search - Abstract
The delivery of videoconferencing psychotherapy (VCP) has been found to be an efficacious, acceptable and feasible treatment modality for individual therapy. However, less is known about the use of VCP for couple and family therapy (CFT). The focus of this systematic review was to examine the efficacy, feasibility and acceptability of using VCP as a treatment delivery modality for CFT. A systematic search was conducted, data relating to efficacy, feasibility and acceptability were extracted from included studies. The search returned 7,112 abstracts, with 37 papers (0.005%) included. The methods of the review were pre-registered (PROSPERO; CRD42018106137). VCP for CFT was demonstrated to be feasible and acceptable. A meta-analysis was not conducted; however, results from the included studies indicate that VCP is an efficacious delivery method for CFT. Recommendations for future research and implications regarding clinical practice are made, which may be of interest to practitioners given the COVID-19 pandemic.
- Published
- 2021
56. Influence of degradation of structure on the behaviour of a full-scale embankment
- Author
-
Panayides, S., Rouainia, M., and Wood, D. Muir
- Subjects
Embankments -- Mechanical properties ,Soil mechanics -- Research ,Finite element method -- Research ,Earth sciences - Abstract
The advanced constitutive model KHSM for structured clays, which incorporates the effects of loss of structure within an elastoplastic framework, has been implemented in a finite element procedure and used to investigate the failure height and pore-water pressures of embankment A constructed at Saint Alban, Quebec. For the purpose of model comparison, simulations were also performed using the standard bubble model (KHM) without destructuration. The numerical predictions of pore-water pressures and settlements are also compared with field measurements. The results clearly demonstrate the importance of including the effects of loss of structure in the analysis. Key words: structured clays, constitutive models, numerical analysis, embankments, full-scale tests, failure. Le modele constitutif avance pour les argiles structurees KHSM, qui integre les effets de la perte de structure dans un cadre elasto-plastique, a ete implante dans une procedure par elements finis et utilise pour etudier la hauteur de rupture et les pressions interstitielles du talus A, construite a Saint-Alban, Quebec. Afin de comparer les modeles, des simulations ont aussi ete realisees avec le modele de bulle standard (KHM) sans destructuration. De plus, les predictions numeriques de pression interstitielle et de tassement ont ete comparees avec les mesures prises sur le terrain. Les resultats demontrent clairement l'importance d'inclure les effets de la perte de structure lors de l'analyse. Mots-cles : argiles structurees, modeles constitutifs, analyse numerique, talus, essai a grande echelle, rupture. [Traduit par la Redaction], Introduction Design and construction of engineered structures on soft soils is becoming more commonplace because of the lack of better land available for construction in both developed and developing regions [...]
- Published
- 2012
- Full Text
- View/download PDF
57. Digital filter based on the Fisher linear discriminant to reduce dead-time paralysis in photon counting.
- Author
-
Shane Z. Sullivan, Paul D. Schmitt, Emma L. DeWalt, Ryan D. Muir, and Garth J. Simpson
- Published
- 2014
- Full Text
- View/download PDF
58. Pore pressures for stability analysis of embankment on soft clay
- Author
-
D. Muir Wood
- Published
- 2020
- Full Text
- View/download PDF
59. Climate warming weakens local adaptation
- Author
-
Colin R. Mahony, Megan Bontrager, Gamble De, Christopher D. Muir, Anna L. Hargreaves, Rachel M. Germain, Amy L. Angert, Elizabeth J. Kleynhans, and Ken A. Thompson
- Subjects
education.field_of_study ,Climatology ,Global warming ,Population ,Environmental science ,Climate change ,Precipitation ,Adaptation ,education ,Evolutionary theory ,Local adaptation - Abstract
Anthropogenic climate change is generating mismatches between the environmental conditions that populations historically experienced and those in which they reside. Understanding how climate change affects population performance is a critical scientific challenge. We combine a quantitative synthesis of field transplant experiments with a novel statistical approach based in evolutionary theory to quantify the effects of temperature and precipitation variability on population performance. We find that species’ average performance is affected by both temperature and precipitation, but populations show signs of local adaptation to temperature only. Contemporary responses to temperature are strongly shaped by the local climates under which populations evolved, resulting in performance declines when temperatures deviate from historic conditions. Adaptation to other local environmental factors is strong, but temperature deviations as small as 2°C erode the advantage that these non-climatic adaptations historically gave populations in their home sites.One sentence summaryClimate change is pulling the thermal rug out from under populations, reducing average performance and eroding their historical home-site advantage.
- Published
- 2020
- Full Text
- View/download PDF
60. Permanent Pacemaker Post Cardiac Surgery: where do we Stand?
- Author
-
Arish Noshirwani, Shubhi Gutpa, Andrew D Muir, Amer Harky, Muhammed Kermali, and Francesca Gatta
- Subjects
medicine.medical_specialty ,Bypass grafting ,RD1-811 ,Cardiac Surgery ,030204 cardiovascular system & hematology ,03 medical and health sciences ,0302 clinical medicine ,Cardiac procedures ,medicine ,Diseases of the circulatory (Cardiovascular) system ,Lead (electronics) ,business.industry ,General Medicine ,Perioperative ,Cardiac surgery ,Pacemaker ,medicine.anatomical_structure ,Conduction Defects ,Anesthesia ,RC666-701 ,cardiovascular system ,Surgery ,Permanent pacemaker ,Cardiology and Cardiovascular Medicine ,business ,Cardiac ischaemia ,Artery - Abstract
Cardiac arrhythmias and requirement for permanent pacemaker (PPM) post open-heart surgery are some of the complications that can contribute to significant morbidities postoperatively and delay in normal recovery if not treated promptly. The reported rate of a PPM following isolated, elective coronary artery bypass grafting is < 1%, while following aortic or mitral valve surgery it is reported to be < 5%. There are several perioperative factors that can contribute to the increased likelihood of PPM requirement including preoperative rhythm, severity and location of cardiac ischaemia, perioperative variables, and the cardiac procedures performed. Optimization of such factors can possibly lead to a lower rate of PPM and, therefore, a lower rate of complications. This literature review focuses on PPM following each procedural type and how to minimize it.
- Published
- 2020
61. Techniques and approaches for revascularisation of left heart coronary diseases
- Author
-
Andrew D Muir, Ka Siu Fan, Shwe Oo, Perry Maskell, and Amer Harky
- Subjects
medicine.medical_specialty ,medicine.medical_treatment ,Myocardial Infarction ,Context (language use) ,Comorbidity ,Coronary Artery Disease ,030204 cardiovascular system & hematology ,Coronary artery disease ,03 medical and health sciences ,0302 clinical medicine ,Left coronary artery ,Percutaneous Coronary Intervention ,Robotic Surgical Procedures ,medicine.artery ,Internal medicine ,medicine ,Clinical endpoint ,Humans ,030212 general & internal medicine ,Myocardial infarction ,Coronary Artery Bypass ,Stroke ,business.industry ,Percutaneous coronary intervention ,General Medicine ,medicine.disease ,Angioscopy ,medicine.anatomical_structure ,Practice Guidelines as Topic ,Cardiology ,business ,Artery - Abstract
Coronary artery disease and its associated clinical sequelae are a significant medical burden to clinicians and patients. Severe coronary artery disease presenting in the context of acute myocardial ischaemia, or stable plaques causing chronic symptoms despite best conservative and pharmacological intervention, are often amenable to further intervention such as coronary artery bypass grafting. This procedure has been extensively compared to newer and less invasive techniques, such as percutaneous coronary intervention, and other minimally invasive procedures such as robotic or endoscopic techniques. This review summarises the current evidence on revascularisation of the left coronary artery system, with particular emphasis on key clinical endpoints of mortality, myocardial infarction, stroke and repeat revascularisation.
- Published
- 2020
62. Quantitative trait locus mapping reveals an independent genetic basis for joint divergence in leaf function, life-history, and floral traits between scarlet monkeyflower (Mimulus cardinalis) populations
- Author
-
Angela M. Stathos, Amy L. Angert, Lila Fishman, Christopher D. Muir, Thomas C. Nelson, Kayli Anderson, and Daniel D. Vanderpool
- Subjects
Natural selection ,Ecological selection ,Pleiotropy ,Evolutionary biology ,Trait ,Selfing ,Biology ,Quantitative trait locus ,Adaptation ,biology.organism_classification ,Mimulus - Abstract
PREMISEAcross taxa, vegetative and floral traits that vary along a fast-slow life-history axis are often correlated with leaf functional traits arrayed along the leaf economics spectrum, suggesting a constrained set of adaptive trait combinations. Such broad-scale convergence may arise from genetic constraints imposed by pleiotropy (or tight linkage) within species, or from natural selection alone. Understanding the genetic basis of trait syndromes and their components is key to distinguishing these alternatives and predicting evolution in novel environments.METHODSWe used a line-cross approach and quantitative trait locus (QTL) mapping to characterize the genetic basis of twenty leaf functional/physiological, life history, and floral traits in hybrids between annualized and perennial populations of scarlet monkeyflower (Mimulus cardinalis).RESULTSWe mapped both single and multi-trait QTLs for life history, leaf function and reproductive traits, but found no evidence of genetic co-ordination across categories. A major QTL for three leaf functional traits (thickness, photosynthetic rate, and stomatal resistance) suggests that a simple shift in leaf anatomy may be key to adaptation to seasonally dry habitats.CONCLUSIONSOur results suggest that the co-ordination of resource-acquisitive leaf physiological traits with a fast life history and more selfing mating system results from environmental selection rather than functional or genetic constraint. Independent assortment of distinct trait modules, as well as a simple genetic basis to leaf physiological traits associated with drought escape, may facilitate adaptation to changing climates.
- Published
- 2020
- Full Text
- View/download PDF
63. The acquisitive-conservative axis of leaf trait variation emerges even in homogeneous environments
- Author
-
Lucas D. Gorné, Sean T. Michaletz, Christopher D. Muir, Martijn Slot, Gerhard Boenisch, Sandra Lavorel, Steven Jansen, Joanne M. Sharpe, Sandra Díaz, Yusuke Onoda, Eduardo Chacón-Madrigal, Vanessa Minden, Koen Kramer, and Biology
- Subjects
0106 biological sciences ,Specific leaf area ,Nitrogen ,Plant Science ,Biology ,Forests ,Poaceae ,010603 evolutionary biology ,01 natural sciences ,Intraspecific competition ,Leaf functional traits ,Filosofie ,purl.org/becyt/ford/1 [https] ,acquisitive syndrome ,common garden experiment ,purl.org/becyt/ford/1.6 [https] ,Ecology ,leaf economics spectrum ,Edaphic ,Fabaceae ,Interspecific competition ,Original Articles ,Plant Leaves ,Philosophy ,Variation (linguistics) ,Phenotype ,conservative syndrome ,Technologie and Innovatie ,intraspecific trait variation ,Trait ,Knowledge Technology and Innovation ,Kennis ,Kennis, Technologie and Innovatie ,010606 plant biology & botany - Abstract
The acquisitive-conservative axis of plant ecological strategies results in a pattern of leaf trait covariation that captures the balance between leaf construction costs and plant growth potential. Studies evaluating trait covariation within species are scarcer, and have mostly dealt with variation in response to environmental gradients. Little work has been published on intraspecific patterns of leaf trait covariation in the absence of strong environmental variation.Methods: We analysed covariation of four leaf functional traits (SLA: specific leaf area, LDMC: leaf dry matter content, Ft: force to tear, and Nm: leaf nitrogen content) in six Poaceae and four Fabaceae species common in the dry Chaco forest of Central Argentina, growing in the field and in a common garden. We compared intraspecific covariation patterns (slopes, correlation and effect size) of leaf functional traits with global interspecific covariation patterns. Additionally, we checked for possible climatic and edaphic factors that could affect the intraspecific covariation pattern.Key Results: We found negative correlations for the LDMC-SLA, Ft-SLA, LDMC-Nm , and Ft-Nm trait pairs. This intraspecific covariation pattern found both in the field and in the common garden and not be explained by climatic or edaphic variation in the field follows the expected acquisitive-conservative axis. At the same time, we found quantitative differences in slopes among different species, and between these intraspecific patterns and the interspecific ones. Many of these differences seem to be idiosyncratic, but some appear consistent among species (e.g.all the intraspecific LDMC-SLA and LDMC-Nm slopes tend to be shallower than the global).Conclusions: Our study indicates that the acquisitive-conservative leaf functional trait covariation pattern occurs at the intraspecific level even in the absence of relevant environmental variation in the field. This suggests a high degree of variation-covariation in leaf functional traits not driven by environmental variables. Fil: Gorne, Lucas Damián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina Fil: Díaz, Sandra Myrna. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina Fil: Minden, Vanessa. University of Oldenburg; Alemania. Vrije Universiteit Brussel; Bélgica Fil: Onoda, Yusuke. Kyoto University. School of Agriculture; Japón Fil: Kramer, Koen. Wageningen University; Países Bajos Fil: Muir, Christopher. University Of Hawaii; Estados Unidos Fil: Michaletz, Sean T. University of British Columbia; Canadá Fil: Lavorel, Sandra. Centre National de la Recherche Scientifique; Francia Fil: Sharpe, Joanne. Sharplex Services, Edgecomb; Estados Unidos Fil: Jansen, Steven. Universitat Ulm; Alemania Fil: Slot, Martijn. Smithsonian Tropical Research Institute; Panamá Fil: Chacon, Maximiliano Eduardo. Universidad de Costa Rica; Costa Rica Fil: Boenisch, Gerhard. Max Planck Institute For Biogeochemistry; Alemania
- Published
- 2020
64. Outcomes in superior transseptal and left atrial approach: Does the number of valves matter?
- Author
-
Andrew D Muir, Amer Harky, and Runzhi Chen
- Subjects
Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,business.industry ,MEDLINE ,medicine.anatomical_structure ,Internal medicine ,Mitral valve ,medicine ,Cardiology ,Humans ,Mitral Valve ,Surgery ,Heart Atria ,Cardiology and Cardiovascular Medicine ,business ,Left atrial approach - Published
- 2020
65. Redo Coronary Artery Bypass Grafting in the era of Advanced PCI
- Author
-
Kellan Masharani, Ter-Er Kusu-Orkar, Andrew D Muir, and Amer Harky
- Subjects
medicine.medical_specialty ,Bypass grafting ,RD1-811 ,medicine.medical_treatment ,Medicine (miscellaneous) ,Coronary Artery Disease ,Revascularization ,Coronary artery disease ,Percutaneous Coronary Intervention ,Internal medicine ,medicine ,Humans ,Diseases of the circulatory (Cardiovascular) system ,cardiovascular diseases ,Coronary Artery Bypass ,Survival rate ,business.industry ,Coronary Stenosis ,Percutaneous coronary intervention ,General Medicine ,Perioperative ,medicine.disease ,Survival Rate ,medicine.anatomical_structure ,Treatment Outcome ,surgical procedures, operative ,RC666-701 ,Conventional PCI ,Cardiology ,Surgery ,Cardiology and Cardiovascular Medicine ,business ,Artery - Abstract
Objective: To review the evidence behind the role and relevance of redo coronary artery bypass grafting (CABG) in the current practice of percutaneous coronary intervention (PCI). Methods: A comprehensive electronic literature search was performed to identify articles that discuss the practice of PCI and redo CABG in patients that require coronary revascularization. All relevant studies are summarized in narrative manner to reflect current indications and preference. Results: The advancement in utilization of PCI has reduced the rate of redo CABG in patients with previous CABG that requires revascularization of an already treated coronary disease or a new onset of coronary artery stenosis. Redo CABG is associated with satisfactory perioperative outcomes but higher mortality at immediate postoperative period when compared to PCI. Conclusion: Redo CABG patients are less likely to develop comorbidities associated with revascularisation, but the operative mortality is higher and long-term survival rates are similar in comparison to PCI. There is a need for further research into the role of redo CABG in the current advanced practice of PCI.
- Published
- 2020
66. Videoconferencing Psychotherapy in the Public Sector: Synthesis and Model for Implementation
- Author
-
Neil Thomas, Denny Meyer, Elizabeth Seabrook, Maja Nedeljkovic, Samuel D Muir, and Kathleen de Boer
- Subjects
Psychotherapist ,020205 medical informatics ,media_common.quotation_subject ,02 engineering and technology ,03 medical and health sciences ,Early adopter ,0302 clinical medicine ,videoconferencing ,0202 electrical engineering, electronic engineering, information engineering ,Technology integration ,Psychology ,030212 general & internal medicine ,media_common ,Original Paper ,implementation science ,business.industry ,Public sector ,public sector ,Change management ,Information technology ,BF1-990 ,psychotherapy ,Psychiatry and Mental health ,Private practice ,Service (economics) ,Industrial and organizational psychology ,Business ,telemedicine ,mental health - Abstract
Background Videoconferencing psychotherapy (VCP) is a growing practice among mental health professionals. Early adopters have predominantly been in private practice settings, and more recent adoption has occurred in larger organizations, such as the military. The implementation of VCP into larger health service providers in the public sector is an important step in reaching and helping vulnerable and at-risk individuals; however, several additional implementation challenges exist for public sector organizations. Objective The aim of this study was to offer an implementation model for effectively introducing VCP into public sector organizations. This model will also provide practical guidelines for planning and executing an embedded service trial to assess the effectiveness of the VCP modality once implemented. Methods An iterative search strategy was employed, drawing on multiple fields of research across mental health, information technology, and organizational psychology. Previous VCP implementation papers were considered in detail to provide a synthesis of the barriers, facilitators, and lessons learned from the implementation attempts in the military and other public sector settings. Results A model was formulated, which draws on change management for technology integration and considers the specific needs for VCP integration in larger organizations. A total of 6 phases were formulated and were further broken down into practical and measurable steps. The model explicitly considers the barriers often encountered in large organizational settings and suggests steps to increase facilitating factors. Conclusions Although the model proposed is time and resource intensive, it draws on a comprehensive understanding of larger organizational needs and the unique challenge that the introduction of VCP presents to such organizations.
- Published
- 2020
67. Dynamic wavelength control of laser pulse profiles at picosecond to nanosecond timescales
- Author
-
D. E. Mittelberger, R. D. Muir, and J. E. Heebner
- Subjects
Atomic and Molecular Physics, and Optics - Abstract
We report on a novel combined laser pulse shaping and dynamic wavelength encoding capability based on a simple architecture implementing direct space to time mapping. There are several potential applications that can be enabled by the ability to control the instantaneous intensity or wavelength of an optical waveform on a picosecond-to-nanosecond timescale. To our knowledge, no known methods can access this temporal regime with a practical architecture. Here, we demonstrate an extension of the Space–Time Induced Linearly Encoded Transcription for Temporal Optimization (STILETTO) technique that can generate optical waveforms with a programmable instantaneous wavelength vs. time. We experimentally demonstrate the technique by generating self-gated spectrograms and show that it can encode dynamic wavelength vs time profiles at timescales not achievable by any other known method.
- Published
- 2022
- Full Text
- View/download PDF
68. A consolidation model for lumpy composite soils in open-pit mining
- Author
-
Ivo Herle, D. Muir Wood, and X. S. Shi
- Subjects
Engineering ,Consolidation (soil) ,business.industry ,Composite number ,0211 other engineering and technologies ,Coal mining ,Compaction ,Open-pit mining ,02 engineering and technology ,Geotechnical Engineering and Engineering Geology ,Permeability (earth sciences) ,020303 mechanical engineering & transports ,0203 mechanical engineering ,Soil water ,Open structure ,Earth and Planetary Sciences (miscellaneous) ,Geotechnical engineering ,business ,021101 geological & geomatics engineering - Abstract
In open-pit coal mining, the excavated clayey cover is dumped without any compaction to form a landfill with a relatively open structure. In this type of material, water flowing through the landfills prefers the inter-lump voids, which have a permeability significantly higher than the clay lumps. With increasing time, the lumps in the upper layer may be partially transformed into a reconstituted soil, occupying the inter-lump voids with consequent decrease in permeability of the landfill. In the study presented here, a consolidation model is proposed based on the double porosity concept and the homogenisation theory. The analysis follows these steps: step 1, a representative volume of lumpy composite soils is divided into four parts and the governing differential equations are formulated based on conservation of mass; step 2, the inter-lump porosity for the lumpy composite structure is formulated as a function of the overall porosity and the porosity of its constituents; step 3, to account for stress (strain) concentrations within the lumpy composite material, a homogenisation relation is used based on analysis of the soil structure; step 4, the hydraulic conductivities of the inter-lump material (lumps) and intra-lump material (reconstituted soil) are approximated by the same set of parameters; step 5, for the lumpy soil, a new relationship between the strains and the absolute velocities of the solid skeleton is proposed, which eliminates the influence of the rigid displacement of the lumps. The model simulations are compared with experimental data, indicating that the proposed model can well represent the consolidation curves of the lumpy composite soil observed in the laboratory.
- Published
- 2018
- Full Text
- View/download PDF
69. Real-time dynamic range and signal to noise enhancement in beam-scanning microscopy by integration of sensor characteristics, data acquisition hardware, and statistical methods.
- Author
-
David J. Kissick, Ryan D. Muir, Shane Z. Sullivan, Robert A. Oglesbee, and Garth J. Simpson
- Published
- 2013
- Full Text
- View/download PDF
70. Surgical Treatment of Atrial Fibrillation: Cutting Through the Edges
- Author
-
Harky, Amer, primary, Bithas, Christiana, additional, Shi Kai Chan, Jeffrey, additional, Snosi, Mostafa, additional, Pousios, Dimitrios, additional, and D Muir, Andrew, additional
- Published
- 2020
- Full Text
- View/download PDF
71. Numerical Modelling of a Shaking Table Test for Soil-Foundation-Superstructure Interaction by Means of a Soil Constitutive Model Implemented in a FEM Code
- Author
-
Abate, G., Massimino, M. R., Maugeri, M., and Wood, D. Muir
- Published
- 2010
72. Restoration of the mycobiome of the endangered Hawaiian mint Phyllostegia kaalaensis increases its resistance to a common powdery mildew
- Author
-
Geoffrey Zahn, Nicole A. Hynson, Anthony S. Amend, Sean O. I. Swift, Christopher D. Muir, Cameron Egan, and Jerry H. Koko
- Subjects
0106 biological sciences ,Ecology ,Resistance (ecology) ,business.industry ,Host (biology) ,Ecological Modeling ,fungi ,Pest control ,Endangered species ,food and beverages ,Plant Science ,Plant disease resistance ,Biology ,Native plant ,010603 evolutionary biology ,01 natural sciences ,Biotechnology ,Disease management (agriculture) ,business ,Ecology, Evolution, Behavior and Systematics ,Powdery mildew ,010606 plant biology & botany - Abstract
Beneficial microbes such as plant mutualistic fungi, hold the promise of ameliorating challenges faced in native plant conservation such as disease management. As an alternative to costly chemical pest control, conservation efforts could potentially harness the benefits of plant mutualistic fungi to aid in defense and disease resistance, but there are few tests of this notion. We set out to test the efficacy of controlling a common foliar pathogen, the powdery mildew Neoerysiphe galeopsidis, by inoculating the endangered Hawaiian plant species Phyllostegia kaalaensis with potentially beneficial members of its wild-type mycobiome. We tested whether inoculating plants with above or belowground fungal mutualists, or both, led to increased disease resistance in the host. We found that while all treatments reduced average disease incidence, colonization by the foliar yeast Moesziomyces aphidis was the only treatment to do so significantly. These results provide an exciting new strategy for plant conservation practices.
- Published
- 2021
- Full Text
- View/download PDF
73. Acute intermittent hypoxia enhances regeneration of surgically repaired peripheral nerves in a manner akin to electrical stimulation
- Author
-
B.M. Arnold, J.R. Nadeau, Gillian D. Muir, Valerie M. K. Verge, and J.M. Johnston
- Subjects
Male ,0301 basic medicine ,Pathology ,medicine.medical_specialty ,Electric Stimulation Therapy ,Stimulation ,03 medical and health sciences ,0302 clinical medicine ,Developmental Neuroscience ,medicine ,Animals ,Peripheral Nerves ,Axon ,Hypoxia ,Tibial nerve ,Spinal cord injury ,Surgical repair ,business.industry ,Intermittent hypoxia ,Motor neuron ,medicine.disease ,Spinal cord ,Nerve Regeneration ,Rats ,030104 developmental biology ,medicine.anatomical_structure ,Neurology ,Rats, Inbred Lew ,Tibial Nerve ,business ,030217 neurology & neurosurgery - Abstract
The intrinsic repair response of injured peripheral neurons is enhanced by brief electrical stimulation (ES) at time of surgical repair, resulting in improved regeneration in rodents and humans. However, ES is invasive. Acute intermittent hypoxia (AIH) - breathing alternate cycles of regular air and air with ~50% normal oxygen levels (11% O2), considered mild hypoxia, is an emerging, promising non-invasive therapy that promotes motor function in spinal cord injured rats and humans. AIH can increase neural activity and under moderately severe hypoxic conditions improves repair of peripherally crushed nerves in mice. Thus, we posited an AIH paradigm similar to that used clinically for spinal cord injury, will improve surgically repaired peripheral nerves akin to ES, including an impact on regeneration-associated gene (RAG) expression–a predictor of growth states. Alterations in early RAG expression were examined in adult male Lewis rats that underwent tibial nerve coaptation repair with either 2 days AIH or normoxia control treatment begun on day 2 post-repair, or 1 h ES treatment (20 Hz) at time of repair. Three days post-repair, AIH or ES treatments effected significant and parallel elevated RAG expression relative to normoxia control at the level of injured sensory and motor neuron cell bodies and proximal axon front. These parallel impacts on RAG expression were coupled with significant improvements in later indices of regeneration, namely enhanced myelination and increased numbers of newly myelinated fibers detected 20 mm distal to the tibial nerve repair site or sensory and motor neurons retrogradely labeled 28 mm distal to the repair site, both at 25 days post nerve repair; and improved return of toe spread function 5–10 weeks post-repair. Collectively, AIH mirrors many beneficial effects of ES on peripheral nerve repair outcomes. This highlights its potential for clinical translation as a non-invasive means to effect improved regeneration of injured peripheral nerves.
- Published
- 2021
- Full Text
- View/download PDF
74. Balloon Expandable Transaortic Transcatheter Valve Implantation with or without Predilation of the Aortic Valve: Results from a Multicenter, Multinational Prospective Registry (ROUTE)
- Author
-
Hardy Baumbach, Martin Thoenes, Nikos Bonaros, J. Lapeze, Julia Dumfarth, Derk Frank, Markus Kofler, Mauro Romano, Dariusz Jagielak, C. Deutsch, Riccardo Cocchieri, Sidney Chocron, Walter B. Eichinger, L. Labrousse, Jean-Philippe Verhoye, K. K. Arne, Matthias Thielmann, Mika Laine, P. Bamlage, D. Muir, Vinayak Bapat, Gino Gerosa, and Marco Aiello
- Subjects
Pulmonary and Respiratory Medicine ,Aortic valve ,medicine.medical_specialty ,Balloon expandable stent ,medicine.anatomical_structure ,business.industry ,medicine ,Surgery ,Radiology ,Cardiology and Cardiovascular Medicine ,business - Published
- 2017
- Full Text
- View/download PDF
75. A neural network for error prediction in a true triaxial apparatus with flexible boundaries
- Author
-
Dihoru, L., Wood, D. Muir, Sadek, T., and Lings, M.
- Published
- 2005
- Full Text
- View/download PDF
76. LV function or geometry assessment for mitral valve surgery?
- Author
-
Amer Harky, Andrew D Muir, Ria Sanghavi, and Ashwini Suresh Chandiramani
- Subjects
Pulmonary and Respiratory Medicine ,Lv function ,medicine.medical_specialty ,business.industry ,Mitral Valve Insufficiency ,Ventricular Function, Left ,medicine.anatomical_structure ,Ventricle ,Internal medicine ,Mitral valve ,Cardiology ,Humans ,Mitral Valve ,Medicine ,Surgery ,Cardiac Surgical Procedures ,Cardiology and Cardiovascular Medicine ,business ,Mitral valve surgery - Published
- 2020
- Full Text
- View/download PDF
77. Pedicled or Skeletonized Internal Mammary Artery in Elective Coronary Artery Bypass? A Systematic Review and Meta-analysis
- Author
-
Beverly MacCarthy-Ofosu, Nina Oguamana, Amer Harky, Peter Eriksen, and Andrew D Muir
- Subjects
medicine.medical_specialty ,medicine.anatomical_structure ,business.industry ,Internal medicine ,Meta-analysis ,medicine ,Mammary artery ,Cardiology ,Cardiology and Cardiovascular Medicine ,business ,Artery - Published
- 2020
- Full Text
- View/download PDF
78. A Systematic Review and Meta-analysis of Transeptal vs Left Atrial Approach for Mitral Valve Surgery
- Author
-
Amer Harky, Andrew D Muir, Dimitrios Pousios, and Arish Noshirwani
- Subjects
medicine.medical_specialty ,business.industry ,Meta-analysis ,Internal medicine ,Cardiology ,medicine ,Electronic database ,Cardiology and Cardiovascular Medicine ,business ,Mitral valve surgery ,Left atrial approach - Abstract
Objective: We sought to compare the clinical outcomes of mitral valve surgery through conventional left atriotomy [LA] and transeptal approach [TS].Methods: Electronic database search was performed...
- Published
- 2020
- Full Text
- View/download PDF
79. Group effects in stone column foundations: model tests
- Author
-
Wood, D. Muir, primary, Hu, W., additional, and Nash, D. F. T., additional
- Published
- 2004
- Full Text
- View/download PDF
80. Age-growth relationships, temperature sensitivity and palaeoclimate-archive potential of the threatened Altiplano cactus
- Author
-
N B, English, D L, Dettman, Q, Hua, J M, Mendoza, D, Muir, K R, Hultine, and D G, Williams
- Subjects
Altiplano ,Acanthochronology ,stable isotopes ,AcademicSubjects/SCI00840 ,cactus ,climate ,Research Article - Abstract
Isotopes in spines of the giant pasacana cactus on the Bolivian Altiplano provide important ecophysiological information for management of this foundation species and record climate information related to Altiplano temperatures and cactus demography., The tall (>4 m), charismatic and threatened columnar cacti, pasacana [Echinopsis atacamensis (Vaupel) Friedrich & G.D. Rowley)], grows on the Bolivian Altiplano and provides environmental and economic value to these extremely cold, arid and high-elevation (~4000 m) ecosystems. Yet very little is known about their growth rates, ages, demography and climate sensitivity. Using radiocarbon in spine dating time series, we quantitatively estimate the growth rate (5.8 and 8.3 cm yr−1) and age of these cacti (up to 430 years). These data and our field measurements yield a survivorship curve that suggests precipitation on the Altiplano is important for this species’ recruitment. Our results also reveal a relationship between nighttime temperatures on the Altiplano and the variation in oxygen isotope values in spines (δ18O). The annual δ18O minimums from 58 years of in-series spine tissue from pasacana on the Altiplano provides at least decadal proxy records of temperature (r = 0.58; P
- Published
- 2019
81. A stomatal model of anatomical tradeoffs between gas exchange and pathogen colonization
- Author
-
Christopher D. Muir
- Subjects
0106 biological sciences ,0301 basic medicine ,anatomy ,stomata ,Plant Science ,lcsh:Plant culture ,Biology ,Photosynthesis ,01 natural sciences ,03 medical and health sciences ,Hypothesis and Theory ,Botany ,lcsh:SB1-1110 ,Colonization ,Pathogen ,Stomatal density ,tradeoff ,model ,photosynthesis ,Explicit model ,scaling ,fungi ,food and beverages ,Limiting ,leaf gas exchange ,030104 developmental biology ,pathogen ,010606 plant biology & botany - Abstract
Stomatal pores control both leaf gas exchange and are one route for infection of internal plant tissues by many foliar pathogens, setting up the potential for tradeoffs between photosynthesis and defense. Anatomical shifts to lower stomatal density and/or size may also limit pathogen colonization, but such developmental changes could permanently reduce the gas exchange capacity for the life of the leaf. I developed and analyzed a spatially explicit model of pathogen colonization on the leaf as a function of stomatal size and density, anatomical traits which partially determine maximum rates of gas exchange. The model predicts greater stomatal size or density increases the probability of colonization, but the effect is most pronounced when the fraction of leaf surface covered by stomata is low. I also derived scaling relationships between stomatal size and density that preserves a given probability of colonization. These scaling relationships set up a potential anatomical conflict between limiting pathogen colonization and minimizing the fraction of leaf surface covered by stomata. Although a connection between gas exchange and pathogen defense has been suggested empirically, this is the first mathematical model connecting gas exchange and pathogen defense via stomatal anatomy. A limitation of the model is that it does not include variation in innate immunity and stomatal closure in response to pathogens. Nevertheless, the model makes predictions that can be tested with experiments and may explain variation in stomatal anatomy among plants. The model is generalizable to many types of pathogens, but lacks significant biological realism that may be needed for precise predictions.
- Published
- 2019
- Full Text
- View/download PDF
82. Surgical Treatment of Atrial Fibrillation: Cutting Through the Edges
- Author
-
Amer Harky, Mostafa Snosi, Andrew D Muir, Dimitrios Pousios, Jeffrey Shi Kai Chan, and Christiana Bithas
- Subjects
lcsh:Diseases of the circulatory (Cardiovascular) system ,medicine.medical_specialty ,medicine.medical_treatment ,lcsh:Surgery ,Heart Surgery ,Management of atrial fibrillation ,forecasting ,Catheter ablation ,Review Article ,030204 cardiovascular system & hematology ,03 medical and health sciences ,0302 clinical medicine ,Heart Rate ,Intervention (counseling) ,catheter ablation ,Atrial Fibrillation ,heart rate ,medicine ,Humans ,Minimally Invasive Surgical Procedures ,atrial fibrillation ,Intensive care medicine ,Surgical treatment ,business.industry ,Atrial fibrillation ,lcsh:RD1-811 ,General Medicine ,medicine.disease ,Hybrid approach ,heart surgery ,Treatment Outcome ,lcsh:RC666-701 ,Catheter Ablation ,Surgery ,Cardiology and Cardiovascular Medicine ,business ,Surgical interventions ,Surgical ablation ,Forecasting - Abstract
Medical management of atrial fibrillation can be complex, challenging and requiring time to prove its effectiveness; furthermore, the response can be refractory and inconsistent if the underlying pathology is not permanently addressed. Surgical ablation has become a key intervention, and since its first intervention in 1987 (the Cox-maze procedure), the technique has evolved from a conventional open method to a minimally invasive technique whilst retaining excellent outcomes. Furthermore, recent advances in the use of a hybrid approach have been established as satisfactory approach in managing atrial fibrillation with satisfactory outcomes. This literature review focuses on the evidence behind the surgical success in managing atrial fibrillation throughout the past, present and the future of these surgical interventions.
- Published
- 2019
83. Recent Ecosystem Changes in Lake Victoria Reflected in Sedimentary Natural and Anthropogenic Organic Compounds
- Author
-
R.E. Hecky, E. Lipiatou, D. Muir, P. Wilkinson, L. Lockhart, and Steven J. Eisenreich
- Subjects
Earth science ,Environmental science ,Ecosystem ,Sedimentary rock ,Natural (archaeology) - Published
- 2019
- Full Text
- View/download PDF
84. Stomatal anatomy coordinates leaf size with Rubisco kinetics in the Balearic Limonium
- Author
-
Jeroni Galmés, Arántzazu Molins, Christopher D. Muir, and Miquel À. Conesa
- Subjects
biology ,Limonium ,fungi ,Botany ,RuBisCO ,Kinetics ,biology.protein ,food and beverages ,Leaf size ,Plant Science ,biology.organism_classification - Abstract
Trait integration arises through both selection on functional coordination and shared developmental pathways. Different anatomical components must both work well and develop together to generate individuals with the appropriate physiology to survive and reproduce in their environment. In this study, we used a common garden experiment and Bayesian multilevel models to test whether stomatal anatomy coordinates leaf gas exchange, Rubisco kinetics, and leaf size across 10 closely related species of Limonium from the Balearic Islands. The results indicate that the anatomical determinants of maximum stomatal conductance, stomatal density and size, were functionally coordinated with Rubisco kinetics – species whose stomatal anatomy was correlated with low stomatal conductance have evolved Rubisco enzymes better adapted to low operational chloroplastic CO2 concentrations. Lower stomatal density was associated with greater leaf size, which can be explained by a greater proportion of pavement cells in large-leaved species. These results suggest that both selection for functional coordination (stomata and Rubisco kinetics) and shared development pathways (stomatal density and leaf area) likely shape patterns of trait integration between species.
- Published
- 2019
- Full Text
- View/download PDF
85. The case for the continued use of the genus name Mimulus for all monkeyflowers
- Author
-
Robert L. Baker, Carrie A. Wu, Liza M. Holeski, Vanessa A. Koelling, Christopher D. Muir, Kathleen G. Ferris, David B. Lowry, Charles B. Fenster, Mario Vallejo-Marín, Jeffrey R. Seemann, Dena L. Grossenbacher, Seema N. Sheth, Jannice Friedman, Yao-Wu Yuan, Christopher T. Ivey, Lila Fishman, Thomas C. Nelson, Tia-Lynn Ashman, Matthew A. Streisfeld, John H. Willis, Joshua R. Puzey, Amy L. Angert, Michele R. Dudash, Alex D. Twyford, Jason P. Sexton, Arielle M. Cooley, Michael C. Rotter, Nicholas J. Kooyers, Kathleen M. Kay, Courtney J. Murren, Megan L. Peterson, Kevin M. Wright, Jennifer M. Coughlan, Benjamin K. Blackman, Kelsey J. R. P. Byers, James M. Sobel, Yaniv Brandvain, and Andrea L. Sweigart
- Subjects
0106 biological sciences ,0301 basic medicine ,Evolutionary Biology ,biology ,media_common.quotation_subject ,Plant Biology ,Plant Science ,Art ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,03 medical and health sciences ,030104 developmental biology ,Genus ,Monkeyflowers ,Theology ,Mimulus ,Ecology, Evolution, Behavior and Systematics ,media_common - Abstract
The genus Mimulus is a well-studied group of plant species, which has for decades allowed researchers to address a wide array of fundamental questions in biology (Wu & al. 2008; Twyford & al. 2015). Linnaeus named the type species of Mimulus (ringens L.), while Darwin (1876) used Mimulus (luteus L.) to answer key research questions. The incredible phenotypic diversity of this group has made it the focus of ecological and evolutionary study since the mid-20th century, initiated by the influential work of Clausen, Keck, and Hiesey as well as their students and collaborators (Clausen & Hiesey 1958; Hiesey & al. 1971, Vickery 1952, 1978). Research has continued on this group of diverse taxa throughout the 20th and into the 21st century (Bradshaw & al. 1995; Schemske & Bradshaw 1999; Wu & al. 2008; Twyford & al. 2015; Yuan 2019), and Mimulus guttatus was one of the first non-model plants to be selected for full genome sequencing (Hellsten & al. 2013). Mimulus has played a key role in advancing our general understanding of the evolution of pollinator shifts (Bradshaw & Schemske 2003; Cooley & al. 2011; Byers & al. 2014), adaptation (Lowry & Willis 2010; Kooyers & al. 2015; Peterson & al. 2016; Ferris & Willis 2018; Troth & al. 2018), speciation (Ramsey & al. 2003; Wright & al. 2013; Sobel & Streisfeld 2015; Zuellig & Sweigart 2018), meiotic drive (Fishman & Saunders 2008), polyploidy (Vallejo-Marín 2012; Vallejo-Marín & al. 2015), range limits (Angert 2009; Sexton et al. 2011; Grossenbacher & al. 2014; Sheth & Angert 2014), circadian rhythms (Greenham & al. 2017), genetic recombination (Hellsten & al. 2013), mating systems (Fenster & Ritland 1994; Dudash & Carr 1998; Brandvain & al. 2014) and developmental biology (Moody & al. 1999; Baker & al. 2011, 2012; Yuan 2019). This combination of a rich history of study coupled with sustained modern research activity is unparalleled among angiosperms. Across many interested parties, the name Mimulus therefore takes on tremendous biological significance and is recognizable not only by botanists, but also by zoologists, horticulturalists, naturalists, and members of the biomedical community. Names associated with a taxonomic group of this prominence should have substantial inertia, and disruptive name changes should be avoided. As members of the Mimulus community, we advocate retaining the genus name Mimulus to describe all monkeyflowers. This is despite recent nomenclature changes that have led to a renaming of most monkeyflower species to other genera.
- Published
- 2019
- Full Text
- View/download PDF
86. Deconvolution uncertainty for power sensors at the National Ignition Facility
- Author
-
Ryan D. Muir and Dominic M. Carrano
- Subjects
Computer science ,Nuclear engineering ,Deconvolution ,National Ignition Facility ,Power (physics) - Published
- 2019
- Full Text
- View/download PDF
87. Increasing Awareness of the Importance of Physical Activity and Healthy Nutrition: Results From a Mixed-Methods Evaluation of a Workplace Program
- Author
-
Olivia Sackett, Denny Meyer, David Ho, Madawa W Jayawar, and Samuel D Muir
- Subjects
Program evaluation ,Adult ,Male ,Applied psychology ,Physical activity ,030229 sport sciences ,Health Promotion ,03 medical and health sciences ,0302 clinical medicine ,Humans ,Orthopedics and Sports Medicine ,Female ,030212 general & internal medicine ,Program Design Language ,Diet, Healthy ,Psychology ,Workplace ,Exercise ,Health Education ,Follow-Up Studies ,Program Evaluation - Abstract
To evaluate the impact of an online workplace program that promotes physical activity and health, while focusing on performance measures relating to physical activity, nutrition, and overall health.The large sample size (more than 18,000 participants) allowed the use of text mining and machine-learning methods to determine what descriptions of the program identify successful outcomes, and hierarchical linear models to determine the most beneficial program modules and features.The program increased overall health and awareness of levels of physical activity and nutrition, especially for people who scored low on these measures initially. Interestingly, although physical activity is the most popular program module, the daily step-tracking process was associated with smaller improvements in overall health.This study finds that the Virgin Pulse Global Challenge is an effective workplace intervention for improving overall health and awareness of physical activity and nutrition. Effectiveness relates to the holistic approach adopted rather than to individual modules in isolation. Future evaluations of workplace health and exercise programs should explore a variety of outcome measures within the rich context provided by open-ended participant experience feedback. In addition, a control group and a follow-up study are required.
- Published
- 2019
88. tealeaves: an R package for modelling leaf temperature using energy budgets
- Author
-
Christopher D. Muir
- Subjects
Computer science ,Software tool ,Energy balance ,Overheating (economics) ,Plant Science ,Biology ,Photosynthesis ,Tools ,Form and function ,Leaf size ,Process engineering ,plant leaves ,Physical model ,plant physiology ,business.industry ,leaf temperature ,Energy budget ,energy balance ,Editor's Choice ,R package ,Boundary layer ,Open source ,leaf size ,Thermal physiology ,Frost (temperature) ,business ,mathematical model - Abstract
Plants must regulate leaf temperature to optimize photosynthesis, control water loss and prevent damage caused by overheating or freezing. Physical models of leaf energy budgets calculate the energy fluxes and leaf temperatures for a given set leaf and environmental parameters. These models can provide deep insight into the variation in leaf form and function, but there are few computational tools available to use these models. Here I introduce a new R package called tealeaves to make complex leaf energy budget models accessible to a broader array of plant scientists. This package enables novice users to start modelling leaf energy budgets quickly while allowing experts to customize their parameter settings. The code is open source, freely available and readily integrates with other R tools for scientific computing. This paper describes the current functionality of tealeaves, but new features will be added in future releases. This software tool will advance new research on leaf thermal physiology to advance our understanding of basic and applied plant science., tealeaves is a new R package to implement complex, customizable leaf energy budget models as part of an open source, transparent workflow.
- Published
- 2019
- Full Text
- View/download PDF
89. Prolonged acute intermittent hypoxia improves forelimb reach-to-grasp function in a rat model of chronic cervical spinal cord injury
- Author
-
Breanna M. Arnold, Behzad M. Toosi, Sally Caine, Gordon S. Mitchell, and Gillian D. Muir
- Subjects
Male ,0301 basic medicine ,Time Factors ,medicine.medical_treatment ,Rat model ,Rats, Sprague-Dawley ,03 medical and health sciences ,0302 clinical medicine ,Developmental Neuroscience ,Forelimb ,medicine ,Animals ,Reach to grasp ,Respiratory system ,Hypoxia ,Spinal cord injury ,Spinal Cord Injuries ,Rehabilitation ,Hand Strength ,business.industry ,Cervical Cord ,Intermittent hypoxia ,Recovery of Function ,medicine.disease ,Rats ,Disease Models, Animal ,030104 developmental biology ,medicine.anatomical_structure ,Neurology ,Anesthesia ,Cervical spinal cord injury ,business ,Psychomotor Performance ,030217 neurology & neurosurgery - Abstract
Repetitive acute intermittent hypoxia (AIH – brief, episodes of low inspired oxygen) elicits spinal motor plasticity, resulting in sustained improvements of respiratory and non-respiratory motor function in both animal models and humans with chronic spinal cord injury (SCI). We previously demonstrated that 7 days of AIH combined with task-specific training improves performance on a skilled locomotor task for at least 3 weeks post-treatment in rats with incomplete SCI. Here we investigated the effect of repetitive AIH administered for 12 wks on a forelimb reach-to-grasp task in a rat model of chronic, incomplete cervical SCI. In a replicated, sham-controlled, randomized and blinded study, male Spraque-Dawley rats were subject to partial hemisection at the 3rd cervical spinal segment, and exposed to daily AIH (10, 5 min episodes of 11% inspired O2; 5 min intervals of 21% O2) or sham normoxia (continuous 21% O2) for 7 days beginning 8 weeks post-injury. Treatments were then reduced to 4 daily treatments per week, and continued for 11 weeks. Performance on 2 pre-conditioned motor tasks, single pellet reaching and horizontal ladder walking, was recorded each week for up to 12 weeks after initiating treatment; performance on spontaneous adhesive removal was also tested. SCI significantly impaired reach-to-grasp task performance 8 weeks post-injury (pre-treatment). Daily AIH improved reaching success by the first week of treatment versus sham controls, and this difference was maintained at 12 weeks (p
- Published
- 2021
- Full Text
- View/download PDF
90. A seasonal comparison of prokaryote numbers, biomass and heterotrophic productivity in waters of the KwaZulu-Natal Bight, South Africa
- Author
-
D Muir, Ursula M. Scharler, and T Kunnen
- Subjects
0106 biological sciences ,Nutrient cycle ,geography ,geography.geographical_feature_category ,bacteria, bacterioplankton, heterotrophic bacteria, heterotrophic bacterial productivity, microbial ecology ,010504 meteorology & atmospheric sciences ,Ecology ,Continental shelf ,010604 marine biology & hydrobiology ,Bacterioplankton ,Subtropics ,Aquatic Science ,Biology ,01 natural sciences ,Nutrient ,Oceanography ,Phytoplankton ,Upwelling ,Hydrography ,Ecology, Evolution, Behavior and Systematics ,0105 earth and related environmental sciences - Abstract
The KwaZulu-Natal Bight is a shallow indentation of the eastern seaboard of South Africa, characterised by a narrow (45 km wide) extension of the continental shelf, with a shelf break at about 100 m. It has a complex hydrography: the waters of the bight are derived from the fast-flowing, southward-trending Agulhas Current, which is fed mostly by the tropical and subtropical surface waters of the South-West Indian Ocean subgyre, which are generally oligotrophic in nature, notably depleted in reduced nitrogen and phosphate except at river mouths and during periodic upwelling of deeper nutrient-rich water. Despite this, the bight is believed to be relatively productive, and it is suggested that efficient nutrient recycling by prokaryotes may sustain primary productivity efficiently, even in the absence of new nutrient inputs. Here we have measured bacterial numbers, biomass and heterotrophic productivity during summer and winter in conjunction with phytoplankton standing stock and factors that influence it. Bacterial distribution closely matched phytoplankton distribution in surface waters, and was highest close to the coast. Bacterial standing stocks were similar to those of oligotrophic systems elsewhere (0.5–5.0 × 105 cells ml–1; 1 × 10–8 to 1.25 × 10–7 g C ml–1) and increased in association with the development of phytoplankton blooms offshore and with inputs of allochthonous material by rivers at the coast. Heterotrophic productivity in summer was lowest in the far south and north of the bight (0.5 × 10–10 g C ml–1 h–1) but higher close to the shore, over shallow banks, and in association with increased phytoplankton abundance over the midshelf (1.0–3.5 × 10–9 g C ml–1 h–1). There were marked seasonal differences with lower bacterial standing stocks (5 × 104 to 2 × 105 cells ml–1; 4–5 × 10–9 to 1–2 × 10–8 g C ml–1) and very low bacterial productivity (4 × 10–11 to 1 × 10–10 g C ml–1 h–1 ) in winter, probably resulting from lowered rates of primary productivity and dissolved organic matter release as well as reduced riverine allochthonous inputs during the winter drought.Keywords: bacteria, bacterioplankton, heterotrophic bacteria, heterotrophic bacterial productivity, microbial ecology
- Published
- 2016
- Full Text
- View/download PDF
91. Dairy and beef breed effects on beef yield, beef quality and profitability: a review
- Author
-
P. D. Muir, Beverley C. Thomson, and Bown
- Subjects
media_common.quotation_subject ,Marbled meat ,Yield (finance) ,0402 animal and dairy science ,food and beverages ,Soil Science ,04 agricultural and veterinary sciences ,Plant Science ,Biology ,040201 dairy & animal science ,Subcutaneous fat ,Breed ,Tenderness ,Animal science ,040103 agronomy & agriculture ,medicine ,0401 agriculture, forestry, and fisheries ,Animal Science and Zoology ,Quality (business) ,Profitability index ,medicine.symptom ,Agronomy and Crop Science ,media_common ,Lean meat - Abstract
Despite the heavy reliance of the New Zealand beef industry on animals produced from the dairy industry (predominantly Friesian and Friesian cross), there is a widespread belief that beef of dairy origin is inferior to beef produced from traditional ‘British’ breeds. This belief is not supported by the scientific literature. There is a large body of work that suggests there is no difference between dairy and traditional British beef breeds in growth potential, lean meat yield, yield of prime cuts, and the quality of meat produced when grazed under similar conditions and slaughtered at the same chronological age or the same level of maturity (fatness). The current New Zealand payment schedule based on carcass weight, fatness and muscularity, undervalues dairy carcasses for having a different pattern of fat distribution (i.e. less subcutaneous fat) and a different muscle shape (poorer conformation score). In New Zealand, the key commercial driver for using traditional beef-bred cattle appears to be ...
- Published
- 2016
- Full Text
- View/download PDF
92. Mechanical Behaviour of Mixtures of Kaolin and Coarse Sand
- Author
-
Kumar, G. V., primary and Wood, D. Muir, additional
- Published
- 1997
- Full Text
- View/download PDF
93. Effect of rearing diet and early post-weaning pasture quality on the life-time growth, meat quality, carcass traits and environmental impact of dairy-beef cattle
- Author
-
Maryann Staincliffe, Beverly C. Thomson, K. Lowe, Paul D. Muir, Muhammad Ajmal Khan, Susan A. McCoard, Robert D. Longhurst, V. T. Burggraaf, K. R. Taukiri, C.R. Craigie, F. W. Knol, and Alan McDermott
- Subjects
geography ,geography.geographical_feature_category ,General Veterinary ,Dairy heifer ,Grazed pasture ,Life time ,Biology ,Beef cattle ,Pasture ,Animal science ,Calf rearing ,Post weaning ,Weaning ,Animal Science and Zoology - Abstract
The effects of divergent calf rearing diets and post-weaning pasture quality on growth, carcass traits, economics and the environment were investigated. Beef x dairy heifer calves were allocated to one of two rearing treatments, followed by a low (L)- or high (H) quality post-weaning pasture diet from 3 to 7 months old, in a 2 × 2 factorial design (n=50 per treatment). The R1 rearing treatment received 4 L milk/day for 5 weeks, then 2 L/day for two weeks plus concentrate pellets ad libitum for 7 weeks in group pens. These calves then grazed pasture from 7 weeks, with pellet-weaning at 12 weeks. The R2 rearing treatment were fed 8 L milk/day for 9 weeks, then 4 L for 2 weeks, weaning at 12 weeks, with ad libitum pasture outdoors after the first week. Cattle were managed as two groups, balanced for treatments, on a pasture-based diet from 7 months until slaughter at 19 to 25 months old. Calves offered the R1 diet grew slower than R2 calves with a 7 kg liveweight difference at 12 weeks (P
- Published
- 2020
- Full Text
- View/download PDF
94. EFFECT OF FUNGAL AND BACTERIAL COLONIES ON SLOPE STABILITY
- Author
-
Wood, D. Muir, primary, Meadows, A., additional, Murray, M. H., additional, and Meadows, P. S., additional
- Published
- 1995
- Full Text
- View/download PDF
95. Promoting Psychological Well-Being at Work by Reducing Stress and Improving Sleep: Mixed-Methods Analysis
- Author
-
Samuel D Muir, Madawa W. Jayawardana, David Ho, Denny Meyer, and Olivia Sackett
- Subjects
Adult ,Male ,productivity ,020205 medical informatics ,Health Informatics ,Sample (statistics) ,02 engineering and technology ,03 medical and health sciences ,0302 clinical medicine ,healthy lifestyle ,Statistical significance ,Surveys and Questionnaires ,0202 electrical engineering, electronic engineering, information engineering ,Humans ,030212 general & internal medicine ,Workplace ,Productivity ,Estimation ,Original Paper ,exercise ,Multilevel model ,Linear model ,Digital health ,Psychological well-being ,Female ,Psychology ,Sleep ,Demography - Abstract
Background: Workplace programs designed to improve the health and psychological well-being of employees are becoming increasingly popular. However, there are mixed reports regarding the effectiveness of such programs and little analysis of what helps people to engage with such programs. Objective: This evaluation of a particularly broad, team-based, digital health and well-being program uses mixed methods to identify the elements of the program that reduce work stress and promote psychological well-being, sleep quality, and productivity of employees. Methods: Participation in the Virgin Pulse Global Challenge program during May to September 2016 was studied. Self-reported stress, sleep quality, productivity, and psychological well-being data were collected both pre- and postprogram. Participant experience data were collected through a third final survey. However, the response rates for the last 2 surveys were only 48% and 10%, respectively. A random forest was used to estimate the probability of the completion of the last 2 surveys based on the preprogram assessment data and the demographic data for the entire sample (N=178,350). The inverse of these estimated probabilities were used as weights in hierarchical linear models in an attempt to address any estimation bias caused by the low response rates. These linear models described changes in psychological well-being, stress, sleep, and productivity over the duration of the program in relation to gender and age, engagement with each of the modules, each of the program features, and participant descriptions of the Virgin Pulse Global Challenge. A 0.1% significance level was used due to the large sample size for the final survey (N=18,653). Results: The final analysis suggested that the program is more beneficial for older people, with 2.9% greater psychological well-being improvements observed on average in the case of women than men (P
- Published
- 2018
96. Geographic variation in reproductive assurance of Clarkia pulchella
- Author
-
Megan Bontrager, Christopher D. Muir, and Amy L. Angert
- Subjects
0106 biological sciences ,Pollination ,Range (biology) ,media_common.quotation_subject ,Clarkia pulchella ,Flowers ,Clarkia ,010603 evolutionary biology ,01 natural sciences ,Pollinator ,Self-pollination ,Symbiosis ,Ecology, Evolution, Behavior and Systematics ,media_common ,biology ,Ecology ,010604 marine biology & hydrobiology ,Reproduction ,food and beverages ,15. Life on land ,biology.organism_classification ,Mating system ,13. Climate action ,Seeds - Abstract
Climate can affect plant populations through direct effects on physiology and fitness, and through indirect effects on their relationships with pollinating mutualists. We therefore expect that geographic variation in climate might lead to variation in plant mating systems. Biogeographic processes, such as range expansion, can also contribute to geographic patterns in mating system traits. We manipulated pollinator access to plants in eight sites spanning the geographic range of Clarkia pulchella to investigate geographic and climatic drivers of fruit production and seed set in the absence of pollinators (reproductive assurance). We examined how reproductive assurance and fruit production varied with the position of sites within the range of the species and with temperature and precipitation. We found that reproductive assurance in C. pulchella was greatest in populations in the northern part of the species’ range and was not well explained by any of the climate variables that we considered. In the absence of pollinators, some populations of C. pulchella have the capacity to increase fruit production, perhaps through resource reallocation, but this response is climate dependent. Pollinators are important for reproduction in this species, and recruitment is sensitive to seed input. The degree of autonomous self-pollination that is possible in populations of this mixed-mating species may be shaped by historic biogeographic processes or variation in plant and pollinator community composition rather than variation in climate.
- Published
- 2018
97. Scaling of plant roots for geotechnical centrifuge tests using juvenile live roots or 3D printed analogues
- Author
-
Jonathan Knappett, G. J. Meijer, Paul D. Hallett, Teng Liang, Kenneth W. Loades, D. Muir Wood, and A. G. Bengough
- Subjects
Centrifuge ,Soil test ,Shear strength (soil) ,ved/biology ,Ultimate tensile strength ,ved/biology.organism_classification_rank.species ,Modulus ,Geotechnical engineering ,Direct shear test ,Root system ,Shrub ,Mathematics - Abstract
Geotechnical centrifuge modelling of vegetated slopes requires appropriately scaled plant roots. Recent studies have independently suggested that juvenile live plants or 3D printing to fabricate root analogues could potentially produce representative prototype model root systems. This paper presents a critical comparison of juvenile versus 3D printed approaches in terms of their representation of root mechanical properties, root morphology and distribution of the additional shear strength generated by the roots with depth. For the 3D printing technique, Acrylonitrile Butadiene Styrene (ABS) plastic material was used, while for live plants, three species (Willow, Gorse and Festulolium grass), corresponding to distinct plant group functional types (tree, shrub and grass), were considered. The tensile strength and Young’s modulus of the ‘roots’ were collected from uniaxial tension tests and shear strength data of rooted soil samples was collected in direct shear. The prototype root characteristics as modelled were then compared with published results for field grown species and the benefits and challenges of using these two modelling approaches is discussed. Finally, some recommendations on realistically modelling plant root systems in centrifuge tests are given.
- Published
- 2018
- Full Text
- View/download PDF
98. Acute intermittent hypoxia and rehabilitative training following cervical spinal injury alters neuronal hypoxia- and plasticity-associated protein expression
- Author
-
Behzad M. Toosi, Atiq Hassan, Gillian D. Muir, Breanna M. Arnold, Valerie M. K. Verge, and Sally Caine
- Subjects
0301 basic medicine ,Nervous system ,Male ,Vascular Endothelial Growth Factor A ,Critical Care and Emergency Medicine ,Protein Expression ,Immunofluorescence ,lcsh:Medicine ,Tropomyosin receptor kinase B ,Biochemistry ,Nervous System ,0302 clinical medicine ,Neurotrophic factors ,Animal Cells ,immune system diseases ,Medicine and Health Sciences ,Gray Matter ,Spinal Cord Injury ,Hypoxia ,lcsh:Science ,Spinal cord injury ,Trauma Medicine ,Neurons ,Motor Neurons ,Multidisciplinary ,Neuronal Plasticity ,Lumbar Vertebrae ,Intermittent hypoxia ,medicine.anatomical_structure ,Spinal Cord ,Neurology ,Acute Disease ,Cervical Vertebrae ,medicine.symptom ,Cellular Types ,Anatomy ,Traumatic Injury ,Research Article ,medicine.medical_specialty ,Motor Proteins ,Nerve Tissue Proteins ,Motor Activity ,Research and Analysis Methods ,Choline O-Acetyltransferase ,Lesion ,03 medical and health sciences ,Molecular Motors ,Internal medicine ,medicine ,Gene Expression and Vector Techniques ,Animals ,Receptor, trkB ,Molecular Biology Techniques ,Immunoassays ,Molecular Biology ,Spinal Cord Injuries ,Molecular Biology Assays and Analysis Techniques ,business.industry ,Brain-Derived Neurotrophic Factor ,lcsh:R ,Biology and Life Sciences ,Proteins ,Cell Biology ,Recovery of Function ,Hypoxia (medical) ,medicine.disease ,Spinal cord ,Hypoxia-Inducible Factor 1, alpha Subunit ,digestive system diseases ,Neuroanatomy ,030104 developmental biology ,Endocrinology ,Rats, Inbred Lew ,Cellular Neuroscience ,Immunologic Techniques ,lcsh:Q ,business ,Neurotrauma ,030217 neurology & neurosurgery ,Neuroscience - Abstract
One of the most promising approaches to improve recovery after spinal cord injury (SCI) is the augmentation of spontaneously occurring plasticity in uninjured neural pathways. Acute intermittent hypoxia (AIH, brief exposures to reduced O2 levels alternating with normal O2 levels) initiates plasticity in respiratory systems and has been shown to improve recovery in respiratory and non-respiratory spinal systems after SCI in experimental animals and humans. Although the mechanism by which AIH elicits its effects after SCI are not well understood, AIH is known to alter protein expression in spinal neurons in uninjured animals. Here, we examine hypoxia- and plasticity-related protein expression using immunofluorescence in spinal neurons in SCI rats that were treated with AIH combined with motor training, a protocol which has been demonstrated to improve recovery of forelimb function in this lesion model. Specifically, we assessed protein expression in spinal neurons from animals with incomplete cervical SCI which were exposed to AIH treatment + motor training either for 1 or 7 days. AIH treatment consisted of 10 episodes of AIH: (5 min 11% O2: 5 min 21% O2) for 7 days beginning at 4 weeks post-SCI. Both 1 or 7 days of AIH treatment + motor training resulted in significantly increased expression of the transcription factor hypoxia-inducible factor-1α (HIF-1α) relative to normoxia-treated controls, in neurons both proximal (cervical) and remote (lumbar) to the SCI. All other markers examined were significantly elevated in the 7 day AIH + motor training group only, at both cervical and lumbar levels. These markers included vascular endothelial growth factor (VEGF), brain-derived neurotrophic factor (BDNF), and phosphorylated and nonphosphorylated forms of the BDNF receptor tropomyosin-related kinase B (TrkB). In summary, AIH induces plasticity at the cellular level after SCI by altering the expression of major plasticity- and hypoxia-related proteins at spinal regions proximal and remote to the SCI. These changes occur under the same AIH protocol which resulted in recovery of limb function in this animal model. Thus AIH, which induces plasticity in spinal circuitry, could also be an effective therapy to restore motor function after nervous system injury.
- Published
- 2018
99. Off-Pump Surgeons' Experience Is Paramount to Delivering High-Quality CABG Outcomes
- Author
-
Bilal H. Kirmani, David P. Taggart, Andrew D Muir, and Lognathen Balacumaraswami
- Subjects
medicine.medical_specialty ,Bypass grafting ,business.industry ,media_common.quotation_subject ,MEDLINE ,030204 cardiovascular system & hematology ,Repeat revascularization ,Surgery ,03 medical and health sciences ,surgical procedures, operative ,0302 clinical medicine ,Propensity score matching ,Medicine ,Quality (business) ,030212 general & internal medicine ,Cardiology and Cardiovascular Medicine ,business ,media_common - Abstract
Chikwe et al. [(1)][1] reported that even in the hands of “experienced” surgeons, off-pump coronary artery bypass grafting (OPCABG) was associated with higher 10-year repeat revascularization (1.4%) and mortality (3.8%) than on-pump CABG (ONCABG). Curiously, despite propensity matching, only
- Published
- 2019
- Full Text
- View/download PDF
100. Delayed Intervention with Intermittent Hypoxia and Task Training Improves Forelimb Function in a Rat Model of Cervical Spinal Injury
- Author
-
Erin J. Prosser-Loose, Gordon S. Mitchell, Atiq Hassan, and Gillian D. Muir
- Subjects
Male ,medicine.medical_specialty ,Spontaneous recovery ,Sensory system ,Walking ,Functional Laterality ,Physical medicine and rehabilitation ,Forelimb ,Neuroplasticity ,medicine ,Animals ,Respiratory system ,Hypoxia, Brain ,Spinal cord injury ,Spinal Cord Injuries ,Neuronal Plasticity ,Hand Strength ,Intermittent hypoxia ,Recovery of Function ,medicine.disease ,Exercise Therapy ,Rats ,medicine.anatomical_structure ,Rats, Inbred Lew ,Concomitant ,Anesthesia ,Cervical Vertebrae ,Neurology (clinical) ,Psychology ,Psychomotor Performance - Abstract
The reduction of motor, sensory and autonomic function below the level of an incomplete spinal cord injury (SCI) has devastating consequences. One approach to restore function is to induce neural plasticity as a means of augmenting spontaneous functional recovery. Acute intermittent hypoxia (AIH-brief exposures to reduced O2 levels alternating with normal O2 levels) elicits plasticity in respiratory and nonrespiratory somatic spinal systems, including improvements in ladder walking performance in rats with incomplete SCI. Here, we determined whether delayed treatment with AIH, with or without concomitant motor training, could improve motor recovery in a rat model of incomplete cervical SCI. In a randomized, blinded, sham-controlled study, rats were exposed to AIH for 7 days beginning at 4 weeks post-SCI, after much spontaneous recovery on a horizontal ladder-crossing task had already occurred. For up to 2 months post-treatment, AIH-treated rats made fewer footslips on the ladder task compared with sham-treated rats. Importantly, concomitant ladder-specific motor training was needed to elicit AIH-induced improvements, such that AIH-treated SCI rats receiving no motor training or nontask-specific treadmill training during the treatment week did not show improvements over sham-treated rats with SCI. AIH treatment combined with task-specific training did not improve recovery on two different reach-to-grasp tasks, however, nor on tasks involving unskilled forepaw use. In brief, our results indicate that task-specific training is needed for AIH to improve ladder performance in a rat model of incomplete cervical SCI.
- Published
- 2015
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.