Field Jet Erosion Tests on Benbrook Dam, Texas

This report summarizes the results of eight field Jet Erosion Tests (JETs) performed on Benbrook Dam, TX. The results from these tests will be used by the U.S. Army Corps of Engineers, Fort Worth District, in assessments of the erosion resistance of the Benbrook Dam with regards to possible overtopping by extreme flooding. The JETs were performed at four different locations, i.e., two locations at the lowest crest elevation and two locations at the mid-slope face of the downstream embankment. Variations in estimated critical hydraulic shear stress and erosion rate values may have been caused by differences in soil composition, i.e., when the material changed from silt/sand to clay. The resulting values of the Erodibility Coefficient, Kd, and Critical Stress, τc, are very useful information in assessing the stability of Benbrook Dam during an overtopping event. Because of the observed natural variability of the materials, combining the erosion parameters presented in this report with the drilling logs and local geology will be imperative for assessing erosion-related failure modes of Benbrook Dam.

The Impact of New SARS-CoV-2 Variants on Vaccine Breakthrough: a pilot study on spreading infection in the communities

Background: Coronavirus disease 2019 (COVID-19) vaccines are effective at helping protect against severe disease and death from variants; however, incident of breakthrough infection in vaccinated patients has been increased. Therefore, we aimed to assess the incidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) new variants of concern in the communities and investigate vaccine breakthrough cases on our laboratory (Ayass Bioscience LLC) confirmed detection of COVID-19 variants in Dallas-Fort Worth (DFW), Texas. Methods: Epidemiologic study has been performed at our laboratory. We studied the viral whole-genome sequence and genotyping analysis on 166 symptomatic cases of COVID-19 which were randomly selected from nasal swab positive cases assessed from June 1st to August 30th, 2021, by reverse transcription polymerase chain reaction (RT-PCR) cycle threshold (CT) values. COVID-19 variants were identified to be dominated by B.1.617.2 (89.2%) and followed by AY.3 (1.8%), B.1.1.7 (4.8%), a combination of B.1.526.1 and B.1.617.2 (3%), B.1.621 (0.6%), and P.2 (0.6%). Result: The CT values showed significant difference among the three age groups: <30 years, 31-60 years, and >60 years by one-way ANOVA (N1: F (2, 118) =4.96, p=0.009; N2: F (2, 118) =4.95, p=0.009). No significant difference was observed by symptom, status of immunization, or vaccine manufacturer. A two-way ANOVA was performed to examine the effect of gender and variant group (Delta and other variants) on the CT values. The analyses revealed a statistically significant interaction between the effect of gender and variant group (N1, F (1.117) = 3.906, p = 0.05; N2, F (1, 117) = 7.402, p = 0.008). Conclusion: Our study shows that Delta, the dominant variant of COVID-19, is spreading in the communities, and vaccine breakthrough cases occurred in the majority of Delta variant (91%) followed by AY.3 (5%), B.1.1.7 (2%) and 2% of the double variant of B.1.526.1 and B.1.617.2. The incidence of the breakthrough cases was not linked to a specific manufacturer. The CT value is likely to associate with age. This study also supports our laboratory's ongoing efforts to sequence the SARS-CoV-2 virus from positive patient samples to identify the new viral variants and possible vaccine breakthrough mutations in the community.

Pediatric Telehealth Expansion in Response to COVID-19

Introduction: Telehealth utilization has been steadily increasing for the past two decades and has been recognized for its ability to access rural and underserved populations. The advent of COVID-19 in March 2020 limited the feasibility of in-person healthcare visits which in turn increased telehealth demand and use. However, the long-term impacts of COVID-19 on the telehealth sector of the healthcare industry, and particularly on pediatric healthcare volume demand and subsequent expansion, are yet to be determined.Objective and Methods: To understand the impact of COVID-19 on telehealth utilization, volume demand, and expansion in one large pediatric healthcare system serving greater Dallas-Fort Worth, Texas, data on telehealth clinic visits by month, pre-COVID and post/current-COVID were compared. A quasi-experimental pretest-posttest design analysis compared telehealth visit counts from 54 ambulatory pediatric health specialties. Pre-post new patient counts were also analyzed via chi square.Results: Total telehealth visit counts significantly increased between March–October 2019 (2,033 visits) compared to March-October 2020 (54,276 visits). Mean monthly telehealth visits increased by 6,530 visits, or 2,569.75% over the same time period (p &lt; 0.0001). In October 2020, total telehealth visits were still 1,194.78% above 2019 levels (345 visits in 2019 vs. 4467 visits in 2020).Discussion: Results here show a substantial volume increase in telehealth-delivered pediatric healthcare and resource utilization as a response to COVID-19. This provides a template for permanent adoption of pediatric telehealth delivery post pandemic. Further investigation is needed to determine impacts upon resource allocation, processes, and general models and standard of care to assist facilities and programs to better address the needs of the pediatric populations they serve in the post-COVID era.

A Texas-specific VS30 map incorporating geology and VS30 observations

A Texas-specific [Formula: see text] map that uses geostatistical kriging integrated with a region-specific geologic proxy, field measurements of [Formula: see text], and P-wave seismogram estimates of [Formula: see text] is developed. The region-specific geologic proxy is used first to predict [Formula: see text] from the surface geologic conditions across the state, and then geostatistical kriging with an external drift is used to incorporate the local [Formula: see text] measurements/estimates into the map. Compared with the [Formula: see text] map of Texas developed from a topographic slope proxy, the Texas-specific [Formula: see text] map predicts larger [Formula: see text] values across much of Texas, except for the Gulf Coast region where the values are similar. The utilization of kriging brings the Texas-specific [Formula: see text] map into better agreement with the in situ measurements and estimates of [Formula: see text]. The sensitivity of predicted ground motions by ShakeMap to changes in [Formula: see text] values is evaluated with a scenario earthquake in the Dallas–Fort Worth area. The results suggest smaller predicted ground motions due to the generally larger values of [Formula: see text] in the Texas-specific [Formula: see text] map as compared to the [Formula: see text] from the topographic proxy.