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Design And Evaluation Of 16s Rrna-Targeted Peptide Nucleic Acid Probes For Whole-Cell Detection Of Members Of The Genus Listeria, Byron F. Brehm-Stecher, Jens J. Hyldig-Nielsen, Eric A. Johnson 2018 Iowa State University

Design And Evaluation Of 16s Rrna-Targeted Peptide Nucleic Acid Probes For Whole-Cell Detection Of Members Of The Genus Listeria, Byron F. Brehm-Stecher, Jens J. Hyldig-Nielsen, Eric A. Johnson

Byron F. Brehm-Stecher

Six fluorescein-labeled peptide nucleic acid oligomers targeting Listeria-specific sequences on the 16S ribosomal subunit were evaluated for their abilities to hybridize to whole cells by fluorescence in situ hybridization (FISH). Four of these probes yielded weak or no fluorescent signals after hybridization and were not investigated further. The remaining two FISH-compatible probes, LisUn-3 and LisUn-11, were evaluated for their reactivities against 22 Listeria strains and 17 other bacterial strains belonging to 10 closely related genera. Hybridization with BacUni-1, a domain-specific eubacterial probe, was used as a positive control for target accessibility in both Listeria spp. and nontarget cells. RNase ...


Design And Evaluation Of Peptide Nucleic Acid Probes For Specific Identification Of Candida Albicans., H. J. Kim, Byron F. Brehm-Stecher 2018 Iowa State University

Design And Evaluation Of Peptide Nucleic Acid Probes For Specific Identification Of Candida Albicans., H. J. Kim, Byron F. Brehm-Stecher

Byron F. Brehm-Stecher

Candida albicans is an important cause of systemic fungal infections, and rapid diagnostics for identifying and differentiating C. albicans from other Candida species are critical for the timely application of appropriate antimicrobial therapy, improved patient outcomes, and pharmaceutical cost savings. In this work, two 28S rRNA-directed peptide nucleic acid-fluorescence in situ hybridization (PNA-FISH) probes, P-Ca726 (targeting a novel region of the ribosome) and P-CalB2208 (targeting a previously reported region), were evaluated. Hybridization conditions were optimized by using both fluorescence microscopy (FM) and flow cytometry (FCM), and probes were screened for specificity and discriminative ability against a panel of C. albicans ...


Re-Entrained Road Dust Pm10 Emission From Selected Streets Of Krakow And Its Impact On Air Quality, Marek Bogacki, Marian Mazur, Robert Oleniacz, Mateusz Rzeszutek, Adriana Szulecka 2018 AGH University o Science and Technology

Re-Entrained Road Dust Pm10 Emission From Selected Streets Of Krakow And Its Impact On Air Quality, Marek Bogacki, Marian Mazur, Robert Oleniacz, Mateusz Rzeszutek, Adriana Szulecka

Robert Oleniacz

Scientific research studies conducted in various parts of the world confirm that PM10 concentrations in urban air depend to a great extent on the resuspension processes of the dust deposited on the road surface. The paper presents the results of the study related to the determination of the re-entrained PM10 emissions from four selected streets of Krakow (Southern Poland) together with the assessment of its impact on air quality. Examined streets are characterised by different traffic intensity (from 500 to over 20 000 vehicles per day) and individual vehicle structure. Dust material sampling and estimation of the PM10 emission were ...


Wrf Forecasts Of Great Plains Nocturnal Low-Level Jet-Driven Mcss. Part Ii: Differences Between Strongly And Weakly Forced Low-Level Jet Environments, Brian J. Squitieri, William A. Gallus Jr. 2018 Iowa State University

Wrf Forecasts Of Great Plains Nocturnal Low-Level Jet-Driven Mcss. Part Ii: Differences Between Strongly And Weakly Forced Low-Level Jet Environments, Brian J. Squitieri, William A. Gallus Jr.

William A. Gallus Jr.

The classic Great Plains southerly low-level jet (LLJ) is a primary factor in sustaining nocturnal convection. This study compares convection-allowing WRF forecasts of LLJ events associated with MCSs in strongly and weakly forced synoptic environments. The depth of the LLJs and magnitude, altitude, and times of the LLJ peak wind were evaluated in observations and WRF forecasts for 31 cases as well as for case subsets of strongly and weakly forced synoptic regimes. LLJs in strongly forced regimes were stronger, deeper, and peaked at higher altitudes and at earlier times compared to weakly forced cases. Mean error MCS-centered composites of ...


The 2015 Plains Elevated Convection At Night Field Project, Bart Geerts, David Parsons, Tammy M. Weckwerth, Michael I. Biggerstaff, Richard D. Clark, Michael C. Coniglio, Belay B. Demoz, Richard A. Ferrare, William A. Gallus Jr., Kevin Haghi, John M. Hanesiak, Petra M. Klein, Kevin R. Knupp, Karen Kosiba, Greg M. McFarquhar, James A. Moore, Amin R. Nehrir, Matthew D. Parker, James O. Pinto, Robert M. Rauber, Russ S. Schumacher, David D. Turner, Qing Wang, Xuguang Wang, Zhien Wang, Joshua Wurman 2018 University of Wyoming

The 2015 Plains Elevated Convection At Night Field Project, Bart Geerts, David Parsons, Tammy M. Weckwerth, Michael I. Biggerstaff, Richard D. Clark, Michael C. Coniglio, Belay B. Demoz, Richard A. Ferrare, William A. Gallus Jr., Kevin Haghi, John M. Hanesiak, Petra M. Klein, Kevin R. Knupp, Karen Kosiba, Greg M. Mcfarquhar, James A. Moore, Amin R. Nehrir, Matthew D. Parker, James O. Pinto, Robert M. Rauber, Russ S. Schumacher, David D. Turner, Qing Wang, Xuguang Wang, Zhien Wang, Joshua Wurman

William A. Gallus Jr.

The central Great Plains region in North America has a nocturnal maximum in warm-season precipitation. Much of this precipitation comes from organized mesoscale convective systems (MCSs). This nocturnal maximum is counterintuitive in the sense that convective activity over the Great Plains is out of phase with the local generation of CAPE by solar heating of the surface. The lower troposphere in this nocturnal environment is typically characterized by a low-level jet (LLJ) just above a stable boundary layer (SBL), and convective available potential energy (CAPE) values that peak above the SBL, resulting in convection that may be elevated, with source ...


Wrf Forecasts Of Great Plains Nocturnal Low-Level Jet-Driven Mcss. Part I: Correlation Between Low-Level Jet Forecast Accuracy And Mcs Precipitation Forecast Skill, Brian J. Squitieri, William A. Gallus Jr. 2018 Iowa State University

Wrf Forecasts Of Great Plains Nocturnal Low-Level Jet-Driven Mcss. Part I: Correlation Between Low-Level Jet Forecast Accuracy And Mcs Precipitation Forecast Skill, Brian J. Squitieri, William A. Gallus Jr.

William A. Gallus Jr.

The Great Plains low-level jet (LLJ) fosters an environment that supports nocturnal mesoscale convective systems (MCSs) across the central United States during the summer months. The current study examines if LLJ forecast accuracy correlates with MCS precipitation forecast skill in 4-km WRF runs. LLJs were classified based on their synoptic background as either strongly forced, cyclonic flow (type C) or weakly forced, anticyclonic flow inertial oscillation driven (type A). Large-scale variables associated with the LLJ were examined. For all LLJs inclusive and the subset of type C LLJs alone, the forecast accuracy of the LLJ total wind direction significantly correlated ...


An Evaluation Of Qpf From The Wrf, Nam, And Gfs Models Using Multiple Verification Methods Over A Small Domain, Haifan Yan, William A. Gallus Jr. 2018 Iowa State University

An Evaluation Of Qpf From The Wrf, Nam, And Gfs Models Using Multiple Verification Methods Over A Small Domain, Haifan Yan, William A. Gallus Jr.

William A. Gallus Jr.

The ARW model was run over a small domain centered on Iowa for 9 months with 4-km grid spacing to better understand the limits of predictability of short-term (12 h) quantitative precipitation forecasts (QPFs) that might be used in hydrology models. Radar data assimilation was performed to reduce spinup problems. Three grid-to-grid verification methods, as well as two spatial techniques, neighborhood and object based, were used to compare the QPFs from the high-resolution runs with coarser operational GFS and NAM QPFs to verify QPFs for various precipitation accumulation intervals and on two grid configurations with different resolutions. In general, NAM ...


Adapting The Sal Method To Evaluate Reflectivity Forecasts Of Summer Precipitation In The Central United States, John R. Lawson, William A. Gallus Jr. 2018 Iowa State University

Adapting The Sal Method To Evaluate Reflectivity Forecasts Of Summer Precipitation In The Central United States, John R. Lawson, William A. Gallus Jr.

William A. Gallus Jr.

The Structure Amplitude Location (SAL)methodwas originally developed to evaluate forecast accumulated-precipitation fields through identification and comparison of objects in both the forecast and the observed fields. This study describes a small modification for use with instantaneous composite-reflectivity forecasts, where objects’ minimum size and reflectivity thresholds are prescribed. Both the original and modified SAL methods are used to evaluate daily 0000UTC 12-km North American Model (NAM) forecasts, against NCEP/EMC 4-km Stage IV accumulated-precipitation estimates, during the summer of 2015 for a central US domain. Results show substantial sensitivity to the reflectivity threshold. This is likely related to sampling more ...


An Initial Assessment Of Radar Data Assimilation On Warm Season Rainfall Forecasts For Use In Hydrologic Models, Ben A. Moser, William A. Gallus Jr., Ricardo Mantilla 2018 Iowa State University

An Initial Assessment Of Radar Data Assimilation On Warm Season Rainfall Forecasts For Use In Hydrologic Models, Ben A. Moser, William A. Gallus Jr., Ricardo Mantilla

William A. Gallus Jr.

The effect of introducing radar data assimilation into the WRF Model to improve high-resolution rainfall forecasts that are used for flash flood forecasting is analyzed. The authors selected 12 heavy rainfall events and performed two WRF 24-h simulations that produced quantitative precipitation forecasts (QPFs) for each, one using the standard configuration in forecast mode (QPF-Cold) and one using radar data assimilated at initialization (QPF-Hot). Simulation outputs are compared with NWS stage IV QPEs for storm placement, area over threshold coverage, and equitable threat scores. The two QPF products and stage IV data are used to force the distributed hydrological model ...


On Contrasting Ensemble Simulations Of Two Great Plains Bow Echoes, John Lawson, William A. Gallus Jr. 2018 Iowa State University

On Contrasting Ensemble Simulations Of Two Great Plains Bow Echoes, John Lawson, William A. Gallus Jr.

William A. Gallus Jr.

Bow echo structures, a subset of mesoscale convective systems (MCSs), are often poorly forecast within deterministic numerical weather prediction model simulations. Among other things, this may be due to the inherent low predictability associated with bow echoes, deficient initial conditions (ICs), and inadequate parameterization schemes. Four different ensemble configurations assessed the sensitivity of the MCSs’ simulated reflectivity and radius of curvature to the following: perturbations in initial and lateral boundary conditions using a global dataset, different microphysical schemes, a stochastic kinetic energy backscatter (SKEB) scheme, and a mix of the previous two. One case is poorly simulated no matter which ...


Ensemble Cloud-Resolving Modelling Of A Historic Back-Building Mesoscale Convective System Over Liguria: The San Fruttuoso Case Of 1915, Antonio Parodi, Luca Ferraris, William A. Gallus Jr., Maurizio Maugeri, Luca Molini, Franco Siccardi, Giorgio Boni 2018 CIMA Research Foundation

Ensemble Cloud-Resolving Modelling Of A Historic Back-Building Mesoscale Convective System Over Liguria: The San Fruttuoso Case Of 1915, Antonio Parodi, Luca Ferraris, William A. Gallus Jr., Maurizio Maugeri, Luca Molini, Franco Siccardi, Giorgio Boni

William A. Gallus Jr.

Highly localized and persistent back-building mesoscale convective systems represent one of the most dangerous flash-flood-producing storms in the north-western Mediterranean area. Substantial warming of the Mediterranean Sea in recent decades raises concerns over possible increases in frequency or intensity of these types of events as increased atmospheric temperatures generally support increases in water vapour content. However, analyses of the historical record do not provide a univocal answer, but these are likely affected by a lack of detailed observations for older events. In the present study, 20th Century Reanalysis Project initial and boundary condition data in ensemble mode are used to ...


Surface-Flux Regulation Of The Coupling Between Cumulus Convection And Baroclinic Waves, William J. Gutowski Jr., Weidong Jiang 2017 Iowa State University

Surface-Flux Regulation Of The Coupling Between Cumulus Convection And Baroclinic Waves, William J. Gutowski Jr., Weidong Jiang

William J. Gutowski, Jr.

The authors examine the role of convection in the dynamics of eddy life cycles through numerical experiments using initial states that are baroclinically and conditionally unstable in midlatitudes. The location of wave-induced convection and its influence on the growing wave depends on how strongly the wave is coupled to the lower boundary through surface fluxes. For all three convective schemes used here (Emanuel, modified Grell, modified Kuo), convective destabilization is favored in the wave’s warm sector when there are no surface fluxes included in the simulation and in the cold sector when there are. Convection is also shallower when ...


Wrf Summer Extreme Daily Precipitation Over The Cordex Arctic, Justin M. Glisan, William J. Gutowski Jr. 2017 glisanj@iastate.edu

Wrf Summer Extreme Daily Precipitation Over The Cordex Arctic, Justin M. Glisan, William J. Gutowski Jr.

William J. Gutowski, Jr.

We analyze daily precipitation extremes produced by a six-member ensemble of the Pan-Arctic Weather Research and Forecasting (WRF) that simulated 19 years on the Coordinated Regional Climate Downscaling Experiment (CORDEX) Arctic domain for the Arctic summer. Attention focuses on four North American analysis regions defined using climatological records, regional weather patterns, and geographical/topographical features. We compare simulated extremes with those occurring at corresponding observing stations in the U.S. National Climate Data Center's Global Summary of the Day. Our analysis focuses on variations in features of the extremes such as magnitudes, spatial scales, and temporal regimes between regions ...


Wcrp Coordinated Regional Downscaling Experiment (Cordex): A Diagnostic Mip For Cmip6, William J. Gutowski Jr., Filippo Giorgi, Bertrand Timbal, Anne Frigon, Daniela Jacob, Hyun-Suk Kang, Krishnan Raghavan, Boram Lee, Christopher Lennard, Grigory Nikulin, Eleanor O’Rourke, Michel Rixen, Silvina Solman, Tannecia Stephenson, Fredolin Tangang 2017 Iowa State University

Wcrp Coordinated Regional Downscaling Experiment (Cordex): A Diagnostic Mip For Cmip6, William J. Gutowski Jr., Filippo Giorgi, Bertrand Timbal, Anne Frigon, Daniela Jacob, Hyun-Suk Kang, Krishnan Raghavan, Boram Lee, Christopher Lennard, Grigory Nikulin, Eleanor O’Rourke, Michel Rixen, Silvina Solman, Tannecia Stephenson, Fredolin Tangang

William J. Gutowski, Jr.

The COordinated Regional Downscaling EXper- iment (CORDEX) is a diagnostic model intercomparison project (MIP) in CMIP6. CORDEX builds on a foundation of previous downscaling intercomparison projects to provide a common framework for downscaling activities around the world. The CORDEX Regional Challenges provide a fo- cus for downscaling research and a basis for making use of CMIP6 global climate model (GCM) output to produce downscaled projected changes in regional climates and as- sess sources of uncertainties in the projections, all of which can potentially be distilled into climate change information for vulnerability, impacts and adaptation studies. CORDEX Flagship Pilot Studies advance ...


Water Vapor Layers In Storm-Fest Rawinsonde Observations, John P. Iselin, William J. Gutowski Jr. 2017 Iowa State University

Water Vapor Layers In Storm-Fest Rawinsonde Observations, John P. Iselin, William J. Gutowski Jr.

William J. Gutowski, Jr.

The STORM-FEST (Fronts Experiment Systems Test) rawinsonde data were analyzed to determine the abundance and characteristics of moist layers within the troposphere. A moist layer was defined as a local maximum in relative humidity with lower relative humidity air above and below. Moist layers under the criteria occur in over half the soundings with an average location between 600 and 500 mb and an average thickness of approximately 120 mb. The layers also appeared to be more nearly aligned with isentropic, rather than isobaric, surfaces. Compositing of relative humidity profiles with a layer at approximately the same level showed an ...


Moist Baroclinic Instability In The Presence Of Surface–Atmosphere Coupling, Weidong Jiang, William J. Gutowski Jr. 2017 Iowa State University

Moist Baroclinic Instability In The Presence Of Surface–Atmosphere Coupling, Weidong Jiang, William J. Gutowski Jr.

William J. Gutowski, Jr.

The influence of convective heating on baroclinic instability in the presence of surface sensible heat and moisture fluxes is investigated. Following previous numerical work, a two-dimensional continuous model on an f plane incorporates diabatic heating effects due to cumulus convection and surface sensible heat flux using parameterizations based on a wave-induced unstable boundary layer and associated moist convective destabilization. The temperature-damping effect of surface sensible heat flux is assumed to decrease exponentially with height, and the vertical distribution of convective heating uses a prescribed profile. The atmosphere is assumed to overlie an oceanic surface. In this configuration, convective heating occurs ...


Some Conceptual And Scaling Evaluations Of Snowmelt Events Forced By Warm Soil, M. Segal, Z. Pan, William J. Gutowski Jr. 2017 Iowa State University

Some Conceptual And Scaling Evaluations Of Snowmelt Events Forced By Warm Soil, M. Segal, Z. Pan, William J. Gutowski Jr.

William J. Gutowski, Jr.

Snowfall occasionally occurs over bare soil with high thermal storage in its upper layer. Quantification and generalization of the potential impact of the thermal storage on episodic snowmelt is evaluated using a scaling approach and assuming negligible net thermal flux at the snow cover top. Soil thermal flux contribution to snowmelt is found to be affected significantly by the level of soil wetness. It is shown that, for a soil temperature of 10°C prior to the snowfall, the contribution of wet soil thermal flux is significant within the first 12 h when compared with intense surface moist enthalpy flux ...


Temperature-Dependent Daily Variability Of Precipitable Water In Special Sensor Microwave/Imager Observations, William J. Gutowski Jr., Elizabeth A. Lindemulder, Kari Jovaag 2017 Iowa State University

Temperature-Dependent Daily Variability Of Precipitable Water In Special Sensor Microwave/Imager Observations, William J. Gutowski Jr., Elizabeth A. Lindemulder, Kari Jovaag

William J. Gutowski, Jr.

We use retrievals of atmospheric precipitable water from satellite microwave observations and analyses of near-surface temperature to examine the relationship between these two fields on daily and longer timescales. The retrieval technique producing the data used here is most effective over the open ocean, so the analysis focuses on the southern hemisphere's extratropics, which have an extensive ocean surface. For both the total and the eddy precipitable water fields, there is a close correspondence between local variations in the precipitable water and near-surface temperature. The correspondence appears particularly strong for synoptic and planetary scale transient eddies. More specifically, the ...


North American Extreme Temperature Events And Related Large Scale Meteorological Patterns: A Review Of Statistical Methods, Dynamics, Modeling, And Trends, Richard Grotjahn, Robert Black, Ruby Leung, Michael F. Wehner, Mathew Barlow, Mike Bosilovich, Alexander Gershunov, William J. Gutowski Jr., John R. Gyakum, Richard E. Katz, Yun-Young Lee, Young-Kwon Lim, Prabhat 2017 University of California Davis

North American Extreme Temperature Events And Related Large Scale Meteorological Patterns: A Review Of Statistical Methods, Dynamics, Modeling, And Trends, Richard Grotjahn, Robert Black, Ruby Leung, Michael F. Wehner, Mathew Barlow, Mike Bosilovich, Alexander Gershunov, William J. Gutowski Jr., John R. Gyakum, Richard E. Katz, Yun-Young Lee, Young-Kwon Lim, Prabhat

William J. Gutowski, Jr.

The objective of this paper is to review statistical methods, dynamics, modeling efforts, and trends related to temperature extremes, with a focus upon extreme events of short duration that affect parts of North America. These events are associated with large scale meteorological patterns (LSMPs). The statistics, dynamics, and modeling sections of this paper are written to be autonomous and so can be read separately. Methods to define extreme events statistics and to identify and connect LSMPs to extreme temperature events are presented. Recent advances in statistical techniques connect LSMPs to extreme temperatures through appropriately defined covariates that supplement more straightforward ...


Atmospheric Water Vapor Transport In Ncep–Ncar Reanalyses: Comparison With River Discharge In The Central United States, William J. Gutowski Jr., Yibin Chen, Zekai Ötles 2017 Iowa State University

Atmospheric Water Vapor Transport In Ncep–Ncar Reanalyses: Comparison With River Discharge In The Central United States, William J. Gutowski Jr., Yibin Chen, Zekai Ötles

William J. Gutowski, Jr.

The authors extract the water transport produced by the National Centers for Environmental Prediction reanalysis for a 10-yr period, 1984–93, and compare its convergence into two river basins with an independent dataset, river discharge (streamflow). Analysis focuses on two basins in the United States, the Upper Mississippi and the Ohio–Tennessee Basins, where the relatively high density of routine upper-air observations might be expected to give the reanalysis its closest rendition of the actual water transport. Over periods of several years, water input by the atmosphere should match water output from these basins in streamflow. However, in both basins ...


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