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Cardiac Amyloidosis: The Role of Magnetic Resonance Imaging

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Open Journal of Clinical Diagnostics 2014年第1期4卷 27-30页

作者： Linda Sim christopher semsarian David Celermajer Rajesh Puranik Department Cardiology Royal Prince Alfred Hospital Sydney Australia

Amyloidosis, an infiltrative disease characterized by deposition of high molecular weight insoluble protein has a low detection rate and poor prognosis with congestive heart failure being the most common cause of death. Although definitive diagnosis is based on endomyocardial biopsy, this is rarely performed due to procedural risk and sampling error. Traditional non-invasive imaging, such as transthoracic echocardiography (TTE) and electrocardiogram (ECG) lacks sensitivity detecting the disease in its early stages. This case report demonstrates the utility of cardiac Magnetic Resonance Imaging in addition to traditional imaging modalities in this often clinically challenging problem.

关键词： Cardiac Amyloidosis Cardiac Magnetic Resonance Imaging (CMR) Transthoracic Echocardiography (TTE) Electrocardiography (ECG) Congestive Cardiac Failure (CCF)

Apples to oranges:environmentally derived,dynamic regulation of serotonin neuron subpopulations in adulthood?

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Neural Regeneration Research 2025年第9期20卷 2596-2597页

作者： christopher J.O’Connell Matthew J.Robson Department of Genetics College of MedicineHarvard UniversityBostonMAUSA James L.Winkle College of Pharmacy Division of Pharmaceutical SciencesUniversity of CincinnatiCincinnatiOHUSA Neuroscience Graduate Program College of MedicineUniversity of CincinnatiCincinnatiOHUSA

Traumatic brain injury(TBI)is a public health problem with an undue economic burden that impacts nearly every age,ethnic,and gender group across the globe(Capizzi et al.,2020).TBIs are often sustained during a dynamic range of exposures to energetic environmental forces and as such outcomes are typically heterogeneous regarding severity and pathology(Capizzi et al.,2020).

关键词： sustained orange dynamic

Protecting miners from coal bursts during development above historic mine workings in Harlan County,KY

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International Journal of Mining Science and Technology 2021年第1期31卷 111-116页

作者： christopher Mark Mine Safety and Health Administration PittsburghPA 15236USA

In order to reach a large,untapped reserve of high-quality coal,D8 Cloverlick Mine proposed to mine a corridor nearly 600 m deep beneath the Benham Spur of Black Mountain,Kentucky’s highest peak.D8 Cloverlick Mine was extracting the Owl seam,but the corridor’s route lay approximately 20 m above century-old mine workings in the C–(Darby)*** to the concern,three serious coal bursts had recently occurred in nearby Owl seam *** of the old workings seemed to indicate that the underlying C–seam had been fully ***,two of the coal bursts had occurred above areas where the C–Seam was also shown as mined *** Safety and Health Administration(MSHA)Technical Support therefore investigated the records of past mining to better understand the old mine *** conditions observed in current Owl seam workings were also compared with the maps of the old C–seam *** study concluded that the presence of hazardous underlying remnants could not be ruled *** mitigate the burst risk,D8 Cloverlick Mine adopted a strategy of stress probe drilling.A self-propelled coal drill was used to auger 11.5-m-long,small diameter holes in advance of *** each hole was drilled,the cuttings were measured to detect the presence of highly stressed *** the crossing was successfully completed without incident.

关键词： Coal bursts Underground mining Room-and-pillar Destressing

An updated empirical model for ground control in *** coal mines

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International Journal of Mining Science and Technology 2021年第2期31卷 163-174页

作者： christopher Mark Mine Safety and Health Administration PittsburghPA 15217USA

Multiple seam interactions are a major source of ground instability in several *** methods are well suited for this problem,because while the mechanics multiple seam interactions are very complex and poorly understood,many mining case histories are available for *** study makes use of an updated database that includes 356 multiseam case histories,including 67 unsuccessful *** paper describes in detail the process used to design the study,collect the data,conduct the statistical analysis,and develop the quantitative *** model can be used for mine planning in multiple seam situations,and has been made available as a module within the Analysis of Coal Pillar Stability(ACPS)computer program.

关键词： Underground Coal Multiseam Ground control Pillar design Empirical

Coal bursts that occur during development: A rock mechanics enigma

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International Journal of Mining Science and Technology 2018年第1期28卷 35-42页

作者： christopher Mark Safety and Health Administration Pittsburgh 15236USA

Coal bursts are typically associated with highly stressed *** bursts occur during retreat mining(longwall mining or pillar recovery) in highly stressed locations like the tailgate corner of the longwall *** are associated with multiple seam ***, a small but significant percentage of coal bursts have occurred during development or in outby locations unaffected by active *** development bursts have been relatively small, but some have been highly *** theory of coal bursts can be complete if it does not account for this type of *** paper focusses on the development mining coal burst experience in the US, putting it into the context of the entire US coal burst *** first documented development coal burst occurred almost exactly 100 years ago during slope drivage at the Sunnyside Mine in *** subsequently had a long history of bursts, mainly during retreat mining but also during *** Colorado mines have also experienced multiple development ***, but by no means all, of the development bursts in these western US coalfields have been associated with known *** the Central Appalachian coalfields, most development bursts have occurred in multiple seam *** some of these cases, however, there was no retreat mining in either *** paper closes with some lessons from this history, with implications for preventing such events in the future.

关键词： Coal Underground Ground control Bursts Multiple seam

Wing, tail, and vocal contributions to the complex acoustic signals of courting Calliope hummingbirds

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Current Zoology 2011年第2期57卷 187-196页

作者： christopher James CLARK Peabody Museum of Natural History Yale University PO Box 208106 New Haven CT 06511 USA Museum of Vertebrate Zoology University of California- Berkeley Berkeley CA USA

Multi-component signals contain multiple signal parts expressed in the same physical modality. One way to identify individual components is if they are produced by different physical mechanisms. Here, I studied the mechanisms generating acoustic signals in the courtship displays of the Calliope hummingbird Stellula calliope. Display dives consisted of three synchronized sound elements, a high-frequency tone （hfl）, a low frequency tone （lft）, and atonal sound pulses （asp）, which were then followed by a frequency-modulated fall. Manipulating any of the rectrices （tail-feathers） of wild males impaired production of the lft and asp but not the hfl or fall, which are apparently vocal. I tested the sound production capabilities of the rectrices in a wind tunnel. Single rectrices could generate the lft but not the asp, whereas multiple rectrices tested together produced sounds sitlfilar to the asp when they fluttered and collided with their neighbors percussively, representing a previously unknown mechanism of sound production. During the shuttle display, a trill is generated by the wings during pulses in which the wingbeat frequency is elevated to 95 Hz, 40% higher than the typical hovering wingbeat frequency. The Calliope hummingbird courtship displays include sounds produced by three independent mechanisms, and thus include a minimum of three acoustic signal components. These acoustic mechanisms have different constraints and thus potentially contain different messages. Producing multiple acoustic signals via multiple mechanisms may be a way to escape the constraints present in any single mechanism .

关键词： Calliope Hummingbird Courtship Multicomponent Signal Sonation Wind Tunnel

Studying turbulence structure near the wall in hydrodynamic flows:An approach based on the Schur decomposition of the velocity gradient tensor

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Journal of Hydrodynamics 2022年第5期34卷 806-825页

作者： christopher J.Keylock School of Architecture Building and Civil EngineeringLoughborough UniversityLeicestershireUK

The Schur decomposition of the velocity gradient tensor(VGT)is an alternative to the classical Cauchy-Stokes decomposition into rotation rate and strain rate ***,there have been several strands of work that have employed this decomposition to examine the physics of turbulence dynamics,including approaches that combine the Schur and Cauchy-Stokes *** are briefly reviewed before the latter approach is set *** partitions the rotation rate and strain rate tensors into normal/local and non-normal/non-local *** then study the relation between the VGT dynamics and ejection-sweep events in a channel flow *** show that the sweeps in particular exhibit novel behaviour compared with either the other quadrants,or the flow in general,with a much-reduced contribution to the dynamics from the non-normal terms above the viscous *** particular,the reduction in the production term that is the interaction between the non-normality and the normal straining reduces in the log-layer as a consequence of an absence of alignment between the non-normal vorticity and the strain rate *** have been early forays into using the Schur transform approach for subgrid-scale modelling in large-eddy simulation(LES)and this would appear to be an exciting way forward.

关键词： Turbulence channel flow velocity gradient tensor Schur decomposition

Pillar design and coal burst experience in Utah Book Cliffs longwall operations

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International Journal of Mining Science and Technology 2021年第1期31卷 33-41页

作者： christopher Mark Michael Gauna Mine Safety and Health Administration Technical Support PittsburghPA 15236USA

Longwall mining has existed in Utah for more than half a *** of this mining occurred at depths of cover that significantly exceed those encountered by most other US longwall *** cover causes high ground stress,which can combine with geology to create a coal burst *** every longwall mine operating within the Utah’s Book Cliffs coalfield has been affected by coal *** design has been a key component in the burst control strategies employed by mines in the Book ***,most longwall mines employed double-use two-entry yield pillar ***-use signifies that the gate system serves first as the headgate,and then later serves as the tailgate for the adjacent *** the 1996 burst fatality at the Aberdeen Mine,the inter-panel barrier design was *** this layout,a wide barrier pillar protects each longwall panel from the previously mined panel,and each gate system is used just *** paper documents the deep cover longwall mining conducted with each type of pillar design,together with the associated coal burst *** of the six longwall mining complexes in the Book Cliffs having a coal burst history is described on a panel-by-panel *** analysis shows that where the mining depth exceeded 450 m,each design has been employed for about 38000 total m of longwall panel *** double-use yield pillar design has been used primarily at depths less than 600 m,however,while the inter-panel barrier design has been used mainly at depths exceeding 600 *** its greater depth of use,the inter-panel barrier gate design has been associated with about one-third as much face region burst activity as the double-use yield pillar design.

关键词： Longwall Ground control Coal burst Pillar design Yield pillar

Social media as passive geo-participation in transportation planning-how effective are topic modeling&sentiment analysis in comparison with citizen surveys?

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Geo-Spatial Information Science 2020年第4期23卷 275-292页

作者： Oliver Lock christopher Pettit City Futures Research Centre Faculty of Built EnvironmentUniversity of New South Wales(UNSW)SydneyAustralia Expanded Perception and Interaction Centre(Epicentre) Faculty of Art&DesignUniversity of New South Wales(UNSW)SydneyAustralia

We live in an era of rapid urbanization as many cities are experiencing an unprecedented rate of population growth and *** transport is playing an increasingly important role in urban mobility with a need to move people and goods efficiently around the *** such pressures on existing public transportation systems,this paper investigates the opportunities to use social media to more effectively engage with citizens and customers using such *** research forms a case study of the use of passively collected forms of big data in cities-focusing on Sydney,***,it examines social media data(Tweets)related to public transport ***,it joins this to longitudinal big data-delay information continuously broadcast by the network over a year,thus forming hundreds of millions of data ***,tones,and sentiment are modeled using machine learning and Natural Language Processing(NLP)*** resulting data,and models,are compared to opinions derived from a citizen survey among *** validity of such data and models versus the intentions of users,in the context of systems that monitor and improve transport performance,are *** such,key recommendations for developing Smart Cities were formed in an applied research context based on these data and techniques.

关键词： Social media smart cities public participation urban sensing transport planning natural language processing machine learning big data