Dust emission from crusted surfaces: Insights from field measurements and modelling

Crusted surfaces can be major sources of mineral dust emission. Quantitative understanding of dust emission from crusted surfaces is limited, because (1) theories on dust emission are not well tested for such surfaces; and (2) modelling is hampered by a lack of input data sufficient to describe the surface conditions. Combining detailed field measurements with physics-based numerical modelling, we present new insights into dust emission from crusted surfaces. Our measurements confirm that crust erodibility and dust-emission intensity can increase or decrease after previous erosion events. To support interpretation of the measurements and to test the applicability of a state-of-the-art parameterisation to simulate dust emission from crusted surfaces, we apply the dust emission scheme of Shao (2004). Saltation flux, which is input to the scheme, is approximated using the parameterisation of Kawamura (1964) and a scaling factor obtained from observations. Limitations of this approach are discussed. Our results show that the dust emission scheme is suitable to estimate dust emission from crusted surfaces if accurate input data and parameters describing the soil-surface condition are provided. The parameters were optimized for each dust event to achieve a best estimate. The variation of the resulting parameter values confirms the observed variability of dust-emission efficiency between the events and provides further evidence that it was caused by variations in crust erodibility. Our study demonstrates that available physics-based dust-emission parameterisations are able to simulate dust emissions under complicated conditions, but also that refined information on the soil-surface conditions are needed as input to the schemes.This study was funded by the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG) grant KL 2932/1-1 awarded as a postdoctoral research fellowship to MK. TEG and RSVP acknowledge support from NASA grant NNX16AH13G. 15 NPW acknowledges support through funding from the Department of Interior, Bureau of Land Management. We thank Ralph Lorenz for providing pressure loggers and the Davis anemometer used on Site F. We also thank Sharalyn Peterson, Justin Van Zee, and Bradley Cooper for field and lab assistance. LPI point data were recorded using DIMA (https://jornada.nmsu.edu/monit-assess/dima). Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. The USDA is an equal opportunity provider and employer. We thank two anonymous reviewers for their positive and helpful comments.Peer ReviewedPostprint (author's final draft

A case report of a heart mass

Introduction: Certain cardiac tumors are asymptomatic and are detected by chance after autopsy. The clinical signs and symptoms of cardiac tumors vary greatly and are determined mainly by the tumor's location and size rather than its histology. Cardiac masses have a broad differential diagnosis, and it is critical to differentiate between neoplastic and non-neoplastic cardiac masses and benign and malignant neoplasms. Surgery is advised in situations of heart failure symptoms, treatment-resistant ventricular arrhythmias, or blockage of the heart's inlet or outlet pathways. Presentation: In this research, a 60-year-old man presented to the hospital with complaints of shortness of breath, and after an echocardiogram and CT scan, he was diagnosed with a right atrial tumor, which required surgery. Conclusion: The patient was sent to the oncology unit for additional treatment after surgery, excision of the mass, and analysis of the pathology sample