Embedded MR fluoroscopy: High temporal resolution real-time imaging during high spatial resolution 3D MRA acquisition

The COVID-19 pandemic is impacting human activities, and in turn energy use and carbon dioxide (CO2) emissions. This research first presented near-real-time high-spatial-resolution(0.1&#176;*0.1&#176;) and high-temporal-resolution(daily) gridded estimates of CO2 emissions for different sectors named Carbon Monitor Gridded Dataset(CMGD). This dataset responds to the growing and urgent need for high-quality, fine-grained CO2 emission estimates to support global emissions monitoring on the refined spatial scale. CMGD is derived from our Carbon Monitor, a near-real-time daily dataset of global CO2 emission from fossil fuel and cement production, including detailed information in 6 sectors and main countries. Based on EDGAR v5.0 gridded CO2 emissions map and other geospatial proxies, we finally constructed CMGD with a high spatial resolution of 0.1 degree. Here, we provided the total emissions of specific countries and analyzed the countries with larger emissions (including the EU). Furthermore, we analyzed the daily emission changes of several typical cities around the world and provided insights on the contributions of various sectors. Through CMGD, we can get a much faster and more fine-grained overview, including timelines that show where and how emissions decreases have corresponded to lockdown measures at the finer spatial scales. The fine-grain and timeliness of CMGD emissions estimates will facilitate more local and adaptive management of CO2 emissions during both the pandemic recovery and the ongoing energy transition.

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Simultaneous measurements of 3D wall shear stress and pulse wave velocity in the murine aortic arch

Journal of Cardiovascular Magnetic Resonance ◽

10.1186/s12968-021-00725-4 ◽

2021 ◽

Vol 23 (1) ◽

Author(s):

Patrick Winter ◽

Kristina Andelovic ◽

Thomas Kampf ◽

Jan Hansmann ◽

Peter Michael Jakob ◽

...

Keyword(s):

Shear Stress ◽

Wall Shear Stress ◽

Pulse Wave Velocity ◽

Aortic Arch ◽

Spatial Resolution ◽

Temporal Resolution ◽

Pulse Wave ◽

High Spatial Resolution ◽

High Temporal Resolution ◽

4D Flow

Abstract Purpose Wall shear stress (WSS) and pulse wave velocity (PWV) are important parameters to characterize blood flow in the vessel wall. Their quantification with flow-sensitive phase-contrast (PC) cardiovascular magnetic resonance (CMR), however, is time-consuming. Furthermore, the measurement of WSS requires high spatial resolution, whereas high temporal resolution is necessary for PWV measurements. For these reasons, PWV and WSS are challenging to measure in one CMR session, making it difficult to directly compare these parameters. By using a retrospective approach with a flexible reconstruction framework, we here aimed to simultaneously assess both PWV and WSS in the murine aortic arch from the same 4D flow measurement. Methods Flow was measured in the aortic arch of 18-week-old wildtype (n = 5) and ApoE−/− mice (n = 5) with a self-navigated radial 4D-PC-CMR sequence. Retrospective data analysis was used to reconstruct the same dataset either at low spatial and high temporal resolution (PWV analysis) or high spatial and low temporal resolution (WSS analysis). To assess WSS, the aortic lumen was labeled by semi-automatically segmenting the reconstruction with high spatial resolution. WSS was determined from the spatial velocity gradients at the lumen surface. For calculation of the PWV, segmentation data was interpolated along the temporal dimension. Subsequently, PWV was quantified from the through-plane flow data using the multiple-points transit-time method. Reconstructions with varying frame rates and spatial resolutions were performed to investigate the influence of spatiotemporal resolution on the PWV and WSS quantification. Results 4D flow measurements were conducted in an acquisition time of only 35 min. Increased peak flow and peak WSS values and lower errors in PWV estimation were observed in the reconstructions with high temporal resolution. Aortic PWV was significantly increased in ApoE−/− mice compared to the control group (1.7 ± 0.2 versus 2.6 ± 0.2 m/s, p < 0.001). Mean WSS magnitude values averaged over the aortic arch were (1.17 ± 0.07) N/m2 in wildtype mice and (1.27 ± 0.10) N/m2 in ApoE−/− mice. Conclusion The post processing algorithm using the flexible reconstruction framework developed in this study permitted quantification of global PWV and 3D-WSS in a single acquisition. The possibility to assess both parameters in only 35 min will markedly improve the analyses and information content of in vivo measurements.

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An automatic contrail tracking algorithm

Atmospheric Measurement Techniques ◽

10.5194/amt-3-1089-2010 ◽

2010 ◽

Vol 3 (4) ◽

pp. 1089-1101 ◽

Cited By ~ 11

Author(s):

M. Vazquez-Navarro ◽

H. Mannstein ◽

B. Mayer

Keyword(s):

Spatial Resolution ◽

Temporal Resolution ◽

High Spatial Resolution ◽

High Temporal Resolution ◽

Cirrus Cloud ◽

Linear Stage ◽

Geostationary Satellites ◽

Rapid Scan ◽

Temporal And Spatial ◽

Resolution Data

Abstract. A method designed to track the life cycle of contrail-cirrus using satellite data with high temporal and spatial resolution, from its formation to the final dissolution of the aviation-induced cirrus cloud is presented. The method follows the evolution of contrails from their linear stage until they are undistinguishable from natural cirrus clouds. Therefore, the study of the effect of aircraft-induced clouds in the atmosphere is no longer restricted to linear contrails and can include contrail-cirrus. The method takes advantage of the high spatial resolution of polar orbiting satellites and the high temporal resolution of geostationary satellites to identify the pixels that belong to an aviation induced cloud. The high spatial resolution data of the MODIS sensor is used for contrail detection, and the high temporal resolution of the SEVIRI sensor in the Rapid Scan mode is used for contrail tracking. An example is included in which the method is applied to the study of a long lived contrail over the bay of Biscay.

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An automatic contrail tracking algorithm

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-3-1439-2010 ◽

2010 ◽

Vol 3 (2) ◽

pp. 1439-1494

Author(s):

M. Vazquez-Navarro ◽

H. Mannstein ◽

B. Mayer

Keyword(s):

Spatial Resolution ◽

Temporal Resolution ◽

High Spatial Resolution ◽

High Temporal Resolution ◽

Cirrus Cloud ◽

Linear Stage ◽

Geostationary Satellites ◽

Rapid Scan ◽

Temporal And Spatial ◽

Resolution Data

Abstract. A method designed to track the life cycle of contrail-cirrus using satellite data with high temporal and spatial resolution, from its formation to the final dissolution of the aviation-induced cirrus cloud is presented. The method follows the evolution of contrails from their linear stage until they are undistinguishable from natural cirrus clouds. Therefore, the study of the effect of aircraft-induced clouds in the atmosphere is no longer restricted to linear contrails and can include contrail-cirrus. The method takes advantage of the high spatial resolution of polar orbiting satellites and the high temporal resolution of geostationary satellites to identify the pixels that belong to an aviation induced cloud. The high spatial resolution data of the MODIS sensor is used for contrail detection, and the high temporal resolution of the SEVIRI sensor in the Rapid Scan mode is used for contrail tracking. An example is included in which the method is applied to the study of a long lived contrail over the bay of Biscay.

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Dual-satellite (Sentinel-2 and Landsat 8) remote sensing of supraglacial lakes in Greenland

10.5194/tc-2018-56 ◽

2018 ◽

Author(s):

Andrew G. Williamson ◽

Alison F. Banwell ◽

Ian C. Willis ◽

Neil S. Arnold

Keyword(s):

Remote Sensing ◽

Spatial Resolution ◽

Temporal Resolution ◽

High Spatial Resolution ◽

Greenland Ice Sheet ◽

High Temporal Resolution ◽

Landsat 8 ◽

Supraglacial Lakes ◽

Dual Sensor ◽

Sentinel 2

Abstract. Although remote sensing is commonly used to monitor supraglacial lakes on the Greenland Ice Sheet, most satellite records must trade-off high spatial resolution for high temporal resolution (e.g. MODIS) or vice versa (e.g. Landsat). Here, we overcome this issue by developing and applying a dual-sensor method that can monitor changes to lake areas and volumes at high spatial resolution (10–30 m) with a frequent revisit time (~ 3 days). We achieve this by mosaicking imagery from the Landsat 8 OLI with imagery from the recently launched Sentinel-2 MSI for a ~ 12 000 km2 area of West Greenland in summer 2016. First, we validate a physically based method for calculating lake depths with Sentinel-2 by comparing measurements against those derived from the available contemporaneous Landsat 8 imagery; we find close correspondence between the two sets of values (R2 = 0.841; RMSE = 0.555 m). This provides us with the methodological basis for automatically calculating lake areas, depths and volumes from all available Landsat 8 and Sentinel-2 images. These automatic methods are incorporated into an algorithm for Fully Automated Supraglacial lake Tracking at Enhanced Resolution (FASTER). The FASTER algorithm produces time series showing lake evolution during the 2016 melt season, including automated rapid (≤ 4 day) lake-drainage identification. With the dual Sentinel-2-Landsat 8 record, we identify 184 rapidly draining lakes, many more than identified with either imagery collection alone (93 with Sentinel-2; 66 with Landsat 8), due to their inferior temporal resolution, or would be possible with MODIS, due to its omission of small lakes

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Dynamic Processes of Nanobubbles: Growth, Collapse, and Coalescence

Journal of Heat Transfer ◽

10.1115/1.4051323 ◽

2021 ◽

Author(s):

Heejun Choi ◽

Calvin Li ◽

G.P. 'Bud' Peterson

Keyword(s):

Spatial Resolution ◽

Temporal Resolution ◽

High Spatial Resolution ◽

Characteristic Length ◽

High Temporal Resolution ◽

X Rays ◽

Force Microscopy ◽

Atomic Force ◽

Theoretical Investigations ◽

Microscopy Techniques

Abstract Abstract Nanobubbles are typically classified as gas/vapor phase cavities in an aqueous solution with a characteristic length of approximately 100 nanometers (nm). The theoretical lifetime of these nanobubbles has been estimated to be less than ~1 microsecond at a diameter of 100 nm based upon the Young-Laplace pressure, but experimental observations have been reported that indicate that they may exist for many hours, or even days. These nanobubbles can be generated by a number of different methods, such as solvent exchange, pressure and/or temperature variations, chemical reactions, or through the electron beam radiolysis of water. The imaging methods utilized to observe these nanobubbles have evolved from low temporal resolution/high spatial resolution, using atomic force microscopy (AFM); or low spatial resolution/high temporal resolution, using optical microscopy (x-rays); or finally, high spatial/high temporal resolution using more recent electron microscopy techniques. A review of the various methods utilized in the nucleation of nanobubbles and the different imaging technologies utilized, along with a summary of the most recent experimental and theoretical investigations of the dynamic behavior and processes of these nanobubbles, including nanobubble growth, nanobubble collapse, and nanobubble coalescence, are presented, discussed and summarized.

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High-Temporal-Resolution High-Spatial-Resolution Spaceborne SAR Based on Continuously Varying PRF

Sensors ◽

10.3390/s17081700 ◽

2017 ◽

Vol 17 (8) ◽

pp. 1700 ◽

Cited By ~ 3

Author(s):

Zhirong Men ◽

Pengbo Wang ◽

Chunsheng Li ◽

Jie Chen ◽

Wei Liu ◽

...

Keyword(s):

Spatial Resolution ◽

Temporal Resolution ◽

High Spatial Resolution ◽

High Temporal Resolution

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A four-channel ICCD framing camera with nanosecond temporal resolution and high spatial resolution

Journal of Modern Optics ◽

10.1080/09500340.2021.1937735 ◽

2021 ◽

pp. 1-9

Author(s):

Yuman Fang ◽

Minrui Zhang ◽

Junfeng Wang ◽

Lehui Guo ◽

Xueling Liu ◽

...

Keyword(s):

Spatial Resolution ◽

Temporal Resolution ◽

High Spatial Resolution ◽

Framing Camera

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Real-time observations of stable isotope dynamics during rainfall and throughfall events

10.5194/hess-2018-301 ◽

2018 ◽

Cited By ~ 3

Author(s):

Barbara Herbstritt ◽

Benjamin Gralher ◽

Markus Weiler

Keyword(s):

Isotopic Composition ◽

Real Time ◽

Temporal Resolution ◽

Tree Canopy ◽

Dead Volume ◽

High Temporal Resolution ◽

Time Lags ◽

Mixing Processes ◽

Hydrologic System ◽

Time Observation

Abstract. The isotopic composition of throughfall is affected by complex exchange, enrichment, and mixing processes in the tree canopy. All interception processes occur simultaneously in space and time generating a complex pattern of throughfall in amount and isotopic composition. This pattern ultimately cascades through the entire hydrologic system and is therefore crucial for studies in catchment hydrology where recharge areas are often forested while reference meteorological stations are generally in the open. For the quasi real-time observation of the isotopic composition of both gross precipitation and throughfall we developed an approach combining an off-the-shelf membrane contactor (Membrana) with a laser-based Cavity Ring-Down Spectrometer (CRDS, Picarro), obtaining isotope readings every two seconds. For the continuous observation of the temporal effect of interception processes two setups with two CRDS instruments in parallel were used analysing gross precipitation and throughfall simultaneously. All devices were kept small to minimize dead volume and thereby, with time-lags of only four minutes, to increase the temporal resolution of isotope observations. Complementarily, meteorological variables were recorded in high temporal resolution at the same location. Comparing these high temporally resolved continuous measurements with discrete liquid or event-based bulk samples, this approach proves to be a powerful tool towards more insight in the very dynamic processes contributing to interception during rainfall events.

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