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Article: X-ray imageable, drug-loaded hydrogel that forms at body temperature for image-guided, needle- based locoregional drug delivery.

Delgado, Jose F / Pritchard, William F / Varble, Nicole / Lopez-Silva, Tania L / Arrichiello, Antonio / Mikhail, Andrew S / Morhard, Robert / Ray, Trisha / Havakuk, Michal M / Nguyen, Alex / Borde, Tabea / Owen, Joshua W / Schneider, Joel P / Karanian, John W / Wood, Bradford J

Research square

2024

Abstract: Liver cancer ranks as the fifth leading cause of cancer-related death globally. Direct intratumoral injections of anti-cancer therapeutics may improve therapeutic efficacy and mitigate adverse effects compared to intravenous injections. Some challenges ... ...

Abstract	Liver cancer ranks as the fifth leading cause of cancer-related death globally. Direct intratumoral injections of anti-cancer therapeutics may improve therapeutic efficacy and mitigate adverse effects compared to intravenous injections. Some challenges of intratumoral injections are that the liquid drug formulation may not remain localized and have unpredictable volumetric distribution. Thus, drug delivery varies widely, highly-dependent upon technique. An x-ray imageable poloxamer 407 (POL)-based drug delivery gel was developed and characterized, enabling real-time feedback. Utilizing three needle devices, POL or a control iodinated contrast solution were injected into an ex vivo bovine liver. The 3D distribution was assessed with cone beam computed tomography (CBCT). The 3D distribution of POL gels demonstrated localized spherical morphologies regardless of the injection rate. In addition, the gel 3D conformal distribution could be intentionally altered, depending on the injection technique. When doxorubicin (DOX) was loaded into the POL and injected, DOX distribution on optical imaging matched iodine distribution on CBCT suggesting spatial alignment of DOX and iodine localization in tissue. The controllability and localized deposition of this formulation may ultimately reduce the dependence on operator technique, reduce systemic side effects, and facilitate reproducibility across treatments, through more predictable standardized delivery.
Language	English
Publishing date	2024-03-06
Publishing country	United States
Document type	Preprint
DOI	10.21203/rs.3.rs-4003679/v1
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Article: HoloLens augmented reality system for transperineal free-hand prostate procedures.

Li, Ming / Mehralivand, Sherif / Xu, Sheng / Varble, Nicole / Bakhutashvili, Ivane / Gurram, Sandeep / Pinto, Peter A / Choyke, Peter L / Wood, Bradford J / Turkbey, Baris

Journal of medical imaging (Bellingham, Wash.)

2023 Volume 10, Issue 2, Page(s) 25001

Abstract: Purpose: An augmented reality (AR) system was developed to facilitate free-hand real-time needle guidance for transperineal prostate (TP) procedures and to overcome the limitations of a traditional guidance grid.: Approach: The HoloLens AR system ... ...

Abstract	Purpose: An augmented reality (AR) system was developed to facilitate free-hand real-time needle guidance for transperineal prostate (TP) procedures and to overcome the limitations of a traditional guidance grid. Approach: The HoloLens AR system enables the superimposition of annotated anatomy derived from preprocedural volumetric images onto a patient and addresses the most challenging part of free-hand TP procedures by providing real-time needle tip localization and needle depth visualization during insertion. The AR system accuracy, or the image overlay accuracy ( Results: The image overlay error was Conclusions: The HoloLens AR system can provide accurate needle guidance for TP interventions. AR support for free-hand lesion targeting is feasible and may provide more flexibility than grid-based methods, due to the real-time 3D and immersive experience during free-hand TP procedures.
Language	English
Publishing date	2023-03-01
Publishing country	United States
Document type	Journal Article
ISSN	2329-4302
ISSN	2329-4302
DOI	10.1117/1.JMI.10.2.025001
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Article ; Online: Morphometric characterization and temporal temperature measurements during hepatic microwave ablation in swine.

Varble, Nicole A / Bakhutashvili, Ivane / Reed, Sheridan L / Delgado, Jose / Tokoutsi, Zoi / Frackowiak, Bruno / Baragona, Marco / Karanian, John W / Wood, Bradford J / Pritchard, William F

PloS one

2023 Volume 18, Issue 8, Page(s) e0289674

Abstract: Purpose: Heat-induced destruction of cancer cells via microwave ablation (MWA) is emerging as a viable treatment of primary and metastatic liver cancer. Prediction of the impacted zone where cell death occurs, especially in the presence of vasculature, ... ...

Abstract	Purpose: Heat-induced destruction of cancer cells via microwave ablation (MWA) is emerging as a viable treatment of primary and metastatic liver cancer. Prediction of the impacted zone where cell death occurs, especially in the presence of vasculature, is challenging but may be achieved via biophysical modeling. To advance and characterize thermal MWA for focal cancer treatment, an in vivo method and experimental dataset were created for assessment of biophysical models designed to dynamically predict ablation zone parameters, given the delivery device, power, location, and proximity to vessels. Materials and methods: MWA zone size, shape, and temperature were characterized and monitored in the absence of perfusion in ex vivo liver and a tissue-mimicking thermochromic phantom (TMTCP) at two power settings. Temperature was monitored over time using implanted thermocouples with their locations defined by CT. TMTCPs were used to identify the location of the ablation zone relative to the probe. In 6 swine, contrast-enhanced CTs were additionally acquired to visualize vasculature and absence of perfusion along with corresponding post-mortem gross pathology. Results: Bench studies demonstrated average ablation zone sizes of 4.13±1.56cm2 and 8.51±3.92cm2, solidity of 0.96±0.06 and 0.99±0.01, ablations centered 3.75cm and 3.5cm proximal to the probe tip, and temperatures of 50 ºC at 14.5±13.4s and 2.5±2.1s for 40W and 90W ablations, respectively. In vivo imaging showed average volumes of 9.8±4.8cm3 and 33.2±28.4cm3 and 3D solidity of 0.87±0.02 and 0.75±0.15, and gross pathology showed a hemorrhagic halo area of 3.1±1.2cm2 and 9.1±3.0cm2 for 40W and 90W ablations, respectfully. Temperatures reached 50ºC at 19.5±9.2s and 13.0±8.3s for 40W and 90W ablations, respectively. Conclusion: MWA results are challenging to predict and are more variable than manufacturer-provided and bench predictions due to vascular stasis, heat-induced tissue changes, and probe operating conditions. Accurate prediction of MWA zones and temperature in vivo requires comprehensive thermal validation sets.
MeSH term(s)	Animals ; Swine ; Liver/pathology ; Liver/surgery ; Microwaves ; Temperature ; Ablation Techniques ; Radiofrequency Ablation
Language	English
Publishing date	2023-08-04
Publishing country	United States
Document type	Journal Article ; Research Support, N.I.H., Intramural ; Research Support, Non-U.S. Gov't
ZDB-ID	2267670-3
ISSN	1932-6203 ; 1932-6203
ISSN (online)	1932-6203
ISSN	1932-6203
DOI	10.1371/journal.pone.0289674
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Article ; Online: Smartphone Augmented Reality Outperforms Conventional CT Guidance for Composite Ablation Margins in Phantom Models.

Lee, Katerina H / Li, Ming / Varble, Nicole / Negussie, Ayele H / Kassin, Michael T / Arrichiello, Antonio / Carrafiello, Gianpaolo / Hazen, Lindsey A / Wakim, Paul G / Li, Xiaobai / Xu, Sheng / Wood, Bradford J

Journal of vascular and interventional radiology : JVIR

2023 Volume 35, Issue 3, Page(s) 452–461.e3

Abstract: Purpose: To develop and evaluate a smartphone augmented reality (AR) system for a large 50-mm liver tumor ablation with treatment planning for composite overlapping ablation zones.: Materials and methods: A smartphone AR application was developed to ... ...

Abstract	Purpose: To develop and evaluate a smartphone augmented reality (AR) system for a large 50-mm liver tumor ablation with treatment planning for composite overlapping ablation zones. Materials and methods: A smartphone AR application was developed to display tumor, probe, projected probe paths, ablated zones, and real-time percentage of the ablated target tumor volume. Fiducial markers were attached to phantoms and an ablation probe hub for tracking. The system was evaluated with tissue-mimicking thermochromic phantoms and gel phantoms. Four interventional radiologists performed 2 trials each of 3 probe insertions per trial using AR guidance versus computed tomography (CT) guidance approaches in 2 gel phantoms. Insertion points and optimal probe paths were predetermined. On Gel Phantom 2, serial ablated zones were saved and continuously displayed after each probe placement/adjustment, enabling feedback and iterative planning. The percentages of tumor ablated for AR guidance versus CT guidance, and with versus without display of recorded ablated zones, were compared among interventional radiologists with pairwise t-tests. Results: The means of percentages of tumor ablated for CT freehand and AR guidance were 36% ± 7 and 47% ± 4 (P = .004), respectively. The mean composite percentages of tumor ablated for AR guidance were 43% ± 1 (without) and 50% ± 2 (with display of ablation zone) (P = .033). There was no strong correlation between AR-guided percentage of ablation and years of experience (r < 0.5), whereas there was a strong correlation between CT-guided percentage of ablation and years of experience (r > 0.9). Conclusions: A smartphone AR guidance system for dynamic iterative large liver tumor ablation was accurate, performed better than conventional CT guidance, especially for less experienced interventional radiologists, and enhanced more standardized performance across experience levels for ablation of a 50-mm tumor.
MeSH term(s)	Humans ; Augmented Reality ; Smartphone ; Tomography, X-Ray Computed/methods ; Surgery, Computer-Assisted ; Phantoms, Imaging ; Liver Neoplasms/diagnostic imaging ; Liver Neoplasms/surgery
Language	English
Publishing date	2023-10-17
Publishing country	United States
Document type	Journal Article
ZDB-ID	1137756-2
ISSN	1535-7732 ; 1051-0443
ISSN (online)	1535-7732
ISSN	1051-0443
DOI	10.1016/j.jvir.2023.10.005
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Zs.A 3720: Show issues

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Article ; Online: A Simple Flow Classification Parameter Can Discriminate Rupture Status in Intracranial Aneurysms.

Asgharzadeh, Hafez / Shahmohammadi, Ali / Varble, Nicole / Levy, Elad I / Meng, Hui / Borazjani, Iman

Neurosurgery

2020 Volume 87, Issue 5, Page(s) E557–E564

Abstract: Background: A simple dimensionless aneurysm number ($An$), which depends on geometry and flow pulsatility, was previously shown to distinguish the flow mode in intracranial aneurysms (IA): vortex mode with a dynamic vortex formation/evolution if $An > 1$ ...

Abstract	Background: A simple dimensionless aneurysm number ($An$), which depends on geometry and flow pulsatility, was previously shown to distinguish the flow mode in intracranial aneurysms (IA): vortex mode with a dynamic vortex formation/evolution if $An > 1$, and cavity mode with a steady shear layer if $An < 1$. Objective: To hypothesize that $An\ > \ 1$ can distinguish rupture status because vortex mode is associated with high oscillatory shear index, which, in turn, is statistically associated with rupture. Methods: The above hypothesis is tested on a retrospective, consecutively collected database of 204 patient-specific IAs. The first 119 cases are assigned to training and the remainder to testing dataset. $An$ is calculated based on the pulsatility index (PI) approximated either from the literature or solving an optimization problem (denoted as$\ \widehat {PI}$). Student's t-test and logistic regression (LR) are used for hypothesis testing and data fitting, respectively. Results: $An$ can significantly discriminate ruptured and unruptured status with 95% confidence level (P < .0001). $An$ (using PI) and $\widehat {An}$ (using $\widehat {PI}$) significantly predict the ruptured IAs (for training dataset $An\!:\ $AUC = 0.85, $\widehat {An}\!:\ $AUC = 0.90, and for testing dataset $An\!:\ $sensitivity = 94%, specificity = 33%, $\widehat {An}\!:\ $sensitivity = 93.1%, specificity = 52.85%). Conclusion: $An > 1$ predicts ruptured status. Unlike traditional hemodynamic parameters such as wall shear stress and oscillatory shear index, $An$ has a physical threshold of one (does not depend on statistical analysis) and does not require time-consuming flow simulations. Therefore, $An$ is a simple, practical discriminator of IA rupture status.
MeSH term(s)	Algorithms ; Aneurysm, Ruptured/diagnosis ; Aneurysm, Ruptured/physiopathology ; Female ; Humans ; Intracranial Aneurysm/diagnosis ; Intracranial Aneurysm/physiopathology ; Logistic Models ; Male ; Middle Aged ; Models, Cardiovascular ; Pulsatile Flow/physiology ; Retrospective Studies ; Stress, Mechanical
Language	English
Publishing date	2020-05-11
Publishing country	United States
Document type	Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
ZDB-ID	135446-2
ISSN	1524-4040 ; 0148-396X
ISSN (online)	1524-4040
ISSN	0148-396X
DOI	10.1093/neuros/nyaa189
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Zs.A 1424: Show issues			Location: Je nach Verfügbarkeit (siehe Angabe bei Bestand) bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular Jg. 1995 - 2021: Lesesall (1.OG) ab Jg. 2022: Lesesaal (EG)
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Article ; Online: In Vivo Characterization of the Swine Airway Morphometry and Motion Based on Computed Tomographic Imaging During Respiration.

Castro, Meryll Grace B / Varble, Nicole A / Yung, Rex C / Wood, Bradford J / Karanian, John W / Pritchard, William F

Journal of biomechanical engineering

2021 Volume 142, Issue 12

Abstract: Swine are a commonly used model in translational pulmonary research. However, in vivo airway morphometry during respiration has not been studied in extensive detail using modern imaging tools. Chest computed tomographic was performed in swine (n = 3) at ... ...

Abstract	Swine are a commonly used model in translational pulmonary research. However, in vivo airway morphometry during respiration has not been studied in extensive detail using modern imaging tools. Chest computed tomographic was performed in swine (n = 3) at multiple stages of respiration. Morphometric parameters of each airway segment at end-expiration and end-inspiration were compared as well as among matched anatomical regions (proximal and distal; ventral, lateral, and dorsal). Analysis included segment diameter, length, ellipticity, and the bifurcation angle between daughter branches. Deformation of the airway during respiration was qualitatively visualized using a point-to-point deformation map. Comparison of airway generation showed airway diameter and length were larger at end-inspiration in the fourth and seventh generations compared to end-expiration. Bifurcation angle was larger at end-inspiration compared to end-expiration. Analysis by anatomical region showed that length and bifurcation angle were larger at inspiration in the distal airway regions only. Regardless of respiratory phase, the lateral regions had larger diameters and lengths compared to the ventral and dorsal regions at similar generations and proximal regions had larger bifurcation angles. The findings that morphological changes were more prevalent in distal airways during respiration was confirmed by analysis of a deformation map. Compared to human airway models, the relative diameter may be smaller and length may be greater in swine in similar airway generations. This morphometric description of the swine airways during respiration may guide conduct of preclinical translational studies, revealing advantages and limitations of swine models for specific evaluations. Such morphometric parameters may directly determine the suitability of the swine model for the study of lung interventions, in terms of recapitulation of human morphometry dynamics.
MeSH term(s)	Animals ; Exhalation ; Lung ; Respiration ; Swine ; Tomography, X-Ray Computed
Language	English
Publishing date	2021-02-17
Publishing country	United States
Document type	Journal Article ; Research Support, N.I.H., Extramural ; Research Support, N.I.H., Intramural ; Research Support, Non-U.S. Gov't
ZDB-ID	243094-0
ISSN	1528-8951 ; 0148-0731
ISSN (online)	1528-8951
ISSN	0148-0731
DOI	10.1115/1.4047550
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Zs.B 2672: Show issues

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Article ; Online: Morphometric characterization and temporal temperature measurements during hepatic microwave ablation in swine.

Nicole A Varble / Ivane Bakhutashvili / Sheridan L Reed / Jose Delgado / Zoi Tokoutsi / Bruno Frackowiak / Marco Baragona / John W Karanian / Bradford J Wood / William F Pritchard

PLoS ONE, Vol 18, Iss 8, p e

2023 Volume 0289674

Abstract: Purpose Heat-induced destruction of cancer cells via microwave ablation (MWA) is emerging as a viable treatment of primary and metastatic liver cancer. Prediction of the impacted zone where cell death occurs, especially in the presence of vasculature, is ...

Abstract	Purpose Heat-induced destruction of cancer cells via microwave ablation (MWA) is emerging as a viable treatment of primary and metastatic liver cancer. Prediction of the impacted zone where cell death occurs, especially in the presence of vasculature, is challenging but may be achieved via biophysical modeling. To advance and characterize thermal MWA for focal cancer treatment, an in vivo method and experimental dataset were created for assessment of biophysical models designed to dynamically predict ablation zone parameters, given the delivery device, power, location, and proximity to vessels. Materials and methods MWA zone size, shape, and temperature were characterized and monitored in the absence of perfusion in ex vivo liver and a tissue-mimicking thermochromic phantom (TMTCP) at two power settings. Temperature was monitored over time using implanted thermocouples with their locations defined by CT. TMTCPs were used to identify the location of the ablation zone relative to the probe. In 6 swine, contrast-enhanced CTs were additionally acquired to visualize vasculature and absence of perfusion along with corresponding post-mortem gross pathology. Results Bench studies demonstrated average ablation zone sizes of 4.13±1.56cm2 and 8.51±3.92cm2, solidity of 0.96±0.06 and 0.99±0.01, ablations centered 3.75cm and 3.5cm proximal to the probe tip, and temperatures of 50 ºC at 14.5±13.4s and 2.5±2.1s for 40W and 90W ablations, respectively. In vivo imaging showed average volumes of 9.8±4.8cm3 and 33.2±28.4cm3 and 3D solidity of 0.87±0.02 and 0.75±0.15, and gross pathology showed a hemorrhagic halo area of 3.1±1.2cm2 and 9.1±3.0cm2 for 40W and 90W ablations, respectfully. Temperatures reached 50ºC at 19.5±9.2s and 13.0±8.3s for 40W and 90W ablations, respectively. Conclusion MWA results are challenging to predict and are more variable than manufacturer-provided and bench predictions due to vascular stasis, heat-induced tissue changes, and probe operating conditions. Accurate prediction of MWA zones and temperature in ...
Keywords	Medicine ; R ; Science ; Q
Subject code	669
Language	English
Publishing date	2023-01-01T00:00:00Z
Publisher	Public Library of Science (PLoS)
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Identification of vortex structures in a cohort of 204 intracranial aneurysms.

Varble, Nicole / Trylesinski, Gabriel / Xiang, Jianping / Snyder, Kenneth / Meng, Hui

Journal of the Royal Society, Interface

2017 Volume 14, Issue 130

Abstract: An intracranial aneurysm (IA) is a cerebrovascular pathology that can lead to death or disability if ruptured. Abnormal wall shear stress (WSS) has been associated with IA growth and rupture, but little is known about the underlying flow physics related ... ...

Abstract	An intracranial aneurysm (IA) is a cerebrovascular pathology that can lead to death or disability if ruptured. Abnormal wall shear stress (WSS) has been associated with IA growth and rupture, but little is known about the underlying flow physics related to rupture-prone IAs. Previous studies, based on analysis of a few aneurysms or partial views of three-dimensional vortex structures, suggest that rupture is associated with complex vortical flow inside IAs. To further elucidate the relevance of vortical flow in aneurysm pathophysiology, we studied 204 patient IAs (56 ruptured and 148 unruptured). Using objective quantities to identify three-dimensional vortex structures, we investigated the characteristics associated with aneurysm rupture and if these features correlate with previously proposed WSS and morphological characteristics indicative of IA rupture. Based on the
MeSH term(s)	Aneurysm, Ruptured/pathology ; Biomechanical Phenomena ; Cerebrovascular Circulation ; Cohort Studies ; Computer Simulation ; Hemodynamics/physiology ; Humans ; Hydrodynamics ; Imaging, Three-Dimensional ; Intracranial Aneurysm/pathology ; Models, Cardiovascular
Language	English
Publishing date	2017-05-23
Publishing country	England
Document type	Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
ZDB-ID	2156283-0
ISSN	1742-5662 ; 1742-5689
ISSN (online)	1742-5662
ISSN	1742-5689
DOI	10.1098/rsif.2017.0021
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Article ; Online: Rupture Resemblance Models May Correlate to Growth Rates of Intracranial Aneurysms: Preliminary Results.

Varble, Nicole / Kono, Kenichi / Rajabzadeh-Oghaz, Hamidreza / Meng, Hui

World neurosurgery

2017 Volume 110, Page(s) e794–e805

Abstract: Background: Treatment of intracranial aneurysms (IAs) is largely guided by IA size and growth. Preliminary investigations have found a relationship between clinical factors and growth; yet, the relationship between morphologic and hemodynamic risk ... ...

Abstract	Background: Treatment of intracranial aneurysms (IAs) is largely guided by IA size and growth. Preliminary investigations have found a relationship between clinical factors and growth; yet, the relationship between morphologic and hemodynamic risk prediction models in IA growth is unknown. Methods: We analyzed serial images of 5 growing and 6 stable IAs. Rupture resemblance scores (RRSs) were calculated from three-dimensional segmented images and computational fluid dynamics simulations. The morphologic (RRS Results: Our results indicate that there is no statistical difference in IAs at the baseline time point; however, growing IAs tend to have a higher aspect ratio (P = 0.066), undulation index (P = 0.086), and RRS Conclusions: Based on this preliminary study, we conjecture that aneurysms that resemble ruptured IAs may grow faster.
MeSH term(s)	Aftercare ; Aged ; Aneurysm, Ruptured/diagnostic imaging ; Aneurysm, Ruptured/physiopathology ; Cerebral Angiography ; Cerebrovascular Circulation ; Disease Progression ; Female ; Humans ; Hydrodynamics ; Imaging, Three-Dimensional ; Intracranial Aneurysm/diagnostic imaging ; Intracranial Aneurysm/physiopathology ; Magnetic Resonance Angiography ; Male ; Middle Aged ; Models, Cardiovascular ; Models, Neurological ; Stress, Mechanical
Language	English
Publishing date	2017-11-24
Publishing country	United States
Document type	Journal Article
ZDB-ID	2534351-8
ISSN	1878-8769 ; 1878-8750
ISSN (online)	1878-8769
ISSN	1878-8750
DOI	10.1016/j.wneu.2017.11.093
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Zs.A 1159: Show issues

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Article ; Online: Flow Instability Detected by High-Resolution Computational Fluid Dynamics in Fifty-Six Middle Cerebral Artery Aneurysms.

Varble, Nicole / Xiang, Jianping / Lin, Ning / Levy, Elad / Meng, Hui

Journal of biomechanical engineering

2016 Volume 138, Issue 6, Page(s) 61009

Abstract: Recent high-resolution computational fluid dynamics (CFD) studies have detected persistent flow instability in intracranial aneurysms (IAs) that was not observed in previous in silico studies. These flow fluctuations have shown incidental association ... ...

Abstract	Recent high-resolution computational fluid dynamics (CFD) studies have detected persistent flow instability in intracranial aneurysms (IAs) that was not observed in previous in silico studies. These flow fluctuations have shown incidental association with rupture in a small aneurysm dataset. The aims of this study are to explore the capabilities and limitations of a commercial cfd solver in capturing such velocity fluctuations, whether fluctuation kinetic energy (fKE) as a marker to quantify such instability could be a potential parameter to predict aneurysm rupture, and what geometric parameters might be associated with such fluctuations. First, we confirmed that the second-order discretization schemes and high spatial and temporal resolutions are required to capture these aneurysmal flow fluctuations. Next, we analyzed 56 patient-specific middle cerebral artery (MCA) aneurysms (12 ruptured) by transient, high-resolution CFD simulations with a cycle-averaged, constant inflow boundary condition. Finally, to explore the mechanism by which such flow instabilities might arise, we investigated correlations between fKE and several aneurysm geometrical parameters. Our results show that flow instabilities were present in 8 of 56 MCA aneurysms, all of which were unruptured bifurcation aneurysms. Statistical analysis revealed that fKE could not differentiate ruptured from unruptured aneurysms. Thus, our study does not lend support to these flow instabilities (based on a cycle-averaged constant inflow as opposed to peak velocity) being a marker for rupture. We found a positive correlation between fKE and aneurysm size as well as size ratio. This suggests that the intrinsic flow instability may be associated with the breakdown of an inflow jet penetrating the aneurysm space.
MeSH term(s)	Computer Simulation ; Female ; Humans ; Hydrodynamics ; Intracranial Aneurysm/physiopathology ; Kinetics ; Male ; Middle Aged ; Models, Biological ; Patient-Specific Modeling
Keywords	covid19
Language	English
Publishing date	2016-06
Publishing country	United States
Document type	Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
ZDB-ID	243094-0
ISSN	1528-8951 ; 0148-0731
ISSN (online)	1528-8951
ISSN	0148-0731
DOI	10.1115/1.4033477
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