Zone In Texas Research Articles

Occurrence and removal of fecal bacteria and microbial source tracking markers in a stormwater detention basin overlying the Edwards Aquifer recharge zone in Texas.

The Edwards Aquifer is the primary water resource for over 2 million people in Texas and faces challenges including fecal contamination of water recharging the aquifer, while effectiveness of best management practices (BMPs) such as detention basins in mitigating fecal pollution remains poorly understood. For this study, the inlet and outlet of a detention basin overlying the aquifer's recharge zone were sampled following storm events using automated samplers. Microbial source tracking and culture-based methods were used to determine the occurrence and removal of fecal genetic markers and fecal coliform bacteria in collected water samples. Markers included E. coli (EC23S857), Enterococcus (Entero1), human (HF183), canine (BacCan), and bird (GFD). Fecal coliforms, EC23S857, and Entero1 were detected following each storm event. GFD was the most frequent host-associated marker detected (91% of samples), followed by BacCan (46%), and HF183 (17%). Wilcoxon signed rank tests indicated significantly lower outlet concentrations for fecal coliforms, EC23S857, and Entero1, but not for HF183, GFD, and BacCan. Higher GFD and BacCan outlet concentrations may be due to factors independent of basin design, such as the non-point source nature of bird fecal contamination and domestic dog care practices in neighborhoods contributing to the basin. Mann-Whitney tests showed marker concentrations were not significantly higher during instances of fecal coliform water quality criterion exceedance, except for E. coli, and that fecal coliform concentrations were not significantly different based on marker detection. Overall, results suggest that the detention basin is effective in attenuating fecal contamination associated with fecal coliforms and the general markers, but not for host-associated markers. Consequently, management efforts should focus on mitigating dog and bird-associated fecal pollution in the study region.

Aggregate (Sand and Gravel) Exploration with 2D Electrical Resistivity Imaging and Test Drilling on the Western Limits of the Balcones Fault Zone in Texas, US

Disclaimer Text and Data Mining. Any automated analytical technique aimed at analysing text and data in digital form in order to generate information including - but not limited to - patterns, trends and correlations (so-called Text and Data Mining) may only be applied if it is done by a research organisation or cultural heritage institution solely for the purpose of (non-commercial) scientific research as mentioned in Clause 3 of Directive (EU) 2019/790 (the Digital Single Market Directive) and Clause 15n of the Dutch Copyright Act [Auteurswet]. Text and Data Mining for commercial purposes is not allowed; all rights in this respect are reserved pursuant to Clause 4 paragraph 3 of the Digital Single Market Directive and Clause 15o paragraph 1 of the Dutch Copyright Act.

“Shovel-Ready”

“Shovel-Ready”

Morphological differentiation of Peromyscus leucopus and P. maniculatus in East Texas

The white-footed deer mouse (Peromyscus leucopus) and the North American deer mouse (P. maniculatus) are widely distributed throughout North America, often with overlapping distributions. These species are believed to be sympatric east of the Balcones fault zone in Texas, but records from natural history collections indicate that P. maniculatus is not common from this region. Given that these two species are notoriously difficult to differentiate morphologically, it is possible that specimens have been incorrectly identified and that P. maniculatus may be rare or not present in East Texas. This study aims to determine if P. leucopus and P. maniculatus can be differentiated morphologically east of the Balcones fault zone in Texas. Cranial and external characters from genetically identified specimens representing each species were analyzed using traditional and geometric morphometric methods. Morphological analyses revealed that genetically identified specimens of P. leucopus and P. maniculatus from east of the Balcones fault zone could be differentiated using a suite of morphological characters. Many of the specimens of P. leucopus used in this study were originally misidentified, suggesting that P. maniculatus is rare in East Texas.

Falsification‐Oriented Signature‐Based Evaluation for Guiding the Development of Land Surface Models and the Enhancement of Observations

AbstractWe develop a novel framework for rigorously evaluating land surface models (LSMs) against observations by recognizing the asymmetry between verification‐ and falsification‐oriented approaches. The former approach cannot completely verify LSMs even though it exhausts every case of consistency between the model predictions and observations, whereas the latter only requires a single case of inconsistency to reveal that there must be something wrong. We argue that it is such an inconsistency that stimulates further development of the models and enhancement of the observations. We therefore propose a falsification‐oriented signature‐based evaluation framework to identify cases of inconsistency between model predictions and observations by extracting signatures based on a set of key assumptions. We apply this framework to evaluate an ensemble of simulations from the Noah‐MP LSM against observations over the continental United States under the three assumptions of water mass conservation, no lateral water flow, and a sufficiently long period of time. Regions showing inconsistencies between the Noah‐MP ensemble simulations and the observations are located in the western mountainous areas, the Yellowstone river basin, the lower Floridan aquifer, the Niobrara river basin at the north tip of the Ogallala aquifer, and the basins downstream of the Balcones fault zones in Texas. These regions coincide with the sites where both advances in theoretical modeling and new observational data (e.g., from the Critical Zone Observatories) have emerged.

Short-term global horizontal irradiance forecasting based on a hybrid CNN-LSTM model with spatiotemporal correlations

Abstract Accurate short-term solar irradiance forecasting is crucial for ensuring the optimum utilization of photovoltaic power generation sources. This study addresses this issue by proposing a spatiotemporal correlation model based on deep learning. The proposed model first applies a convolutional neural network (CNN) to extract spatial features from a two-dimensional matrix composed of meteorological parameters associated with a target site and its neighboring sites. Then, a long short-term memory (LSTM) network is applied to extract temporal features from historical solar irradiance time-series data associated with the target site. Finally, the spatiotemporal correlations are merged to predict global horizontal irradiance one hour in advance. The prediction performance and generalization ability of the proposed CNN-LSTM model are evaluated within a whole year, under diverse seasons and sky conditions. Three datasets are involved for case studies, which are collected from 34 locations spread across three different climate zones in Texas, USA. Moreover, the performance of the CNN-LSTM model is compared with those obtained using the CNN, LSTM, and other benchmark models based on five evaluation metrics. The results indicate that the proposed model has advantages over the other models considered and provides a good alternative for short-term solar radiation prediction.

Psychopharmacology Utilization Among Children with Anxiety and Obsessive-Compulsive and Related Disorders Following Hurricane Katrina.

This study aimed to examine the impact of Hurricane Katrina exposure on medication utilization among children with pre-existing anxiety and obsessive-compulsive and related disorders (OCRDs). Medicaid claims data from 2004 to 2006 were analyzed. Children with pre-existing anxiety/OCRDs were compared as a function of those living in a Louisiana disaster area, Louisiana non-disaster area, or Texas in terms of filled prescriptions and average days medication supply. This was further examined as a function of disorder/medication type. Prescriptions filled and average days medication supply were lower for those who resided in the disaster area of Louisiana relative to non-disaster zones in Texas (but not Louisiana). Children with OCD who lived in a disaster zone in Louisiana had 16.6 fewer days supply of antidepressants relative to youth in Texas. Similarly, children with PTSD who lived in a disaster zone in Louisiana had approximately 7 fewer days supply of stimulant medication relative to those who lived in Texas. Medication utilization was reduced for those youth directly exposed to Katrina relative to children in Texas, suggesting potential service disruption. Children with OCD and PTSD may be more likely to experience treatment disruption. Following disasters, particular attention should be given to ensuring continued treatment access for youth with pre-existing anxiety and OCRDs (as well as other conditions).

Effects of Drought on Crop Production and Cropping Areas in Texas

Core Ideas Drought causes significant yield reductions both for rainfed and irrigated crops. Drought can have impact on cropping areas and crop yield. Changing crop types can be used to cope with drought challenges during drought periods. Increased crop yield is required to meet the needs of future population growth, but drought causes significant yield reductions for rainfed and irrigated crops. This study evaluates the impact of drought on crop yield and cropping area over 10 climate zones in Texas from 2008 to 2016. It also depicts the spatiotemporal distribution of crop yield and cropping area changes at each climate zone across the state. We analyzed the impact of drought on crop yields and cropping areas before and after the 2011 severe drought using annual crop yields of four major crops. Results show that drought had a greater impact on winter wheat (Triticum aestivum L.) and corn (Zea mays L.) and lesser impact on cotton (Gossypium spp.) and sorghum [Sorghum bicolor (L.) Moench] production across Texas. Cotton and corn hectarages were reduced during the drought period and increased after that, whereas winter wheat hectarage was reduced in the northern climate zones and increased in the southern climate zones before the drought. Results also indicate that drought impact on crop production may be reduced by replacing water‐demanding crops such as corn with drought‐tolerant crops such as sorghum and expanding irrigation hectarage during drought periods. It may be beneficial for Texas agricultural production to increase the hectarage of sorghum and other grains especially during drought periods. This study provides valuable information that can be used to adopt appropriate measures to cope with future drought challenges in drought‐prone regions.

Current and Historical Extent of Phenotypic Variation in the Tufted and Black-crested Titmouse (Paridae) Hybrid Zone in the Southern Great Plains

Hybrid zones, where phenotypically distinct populations interbreed, should expand or contract until reaching a balance between selection and dispersal. Few studies examine multiple contacts within one species complex to compare how their extent changes over time. Black-crested and Tufted Titmice (Baeolophus atricristatus and B. bicolor) hybridize extensively within a narrow zone in Texas and southwestern Oklahoma. In Texas, hybridization has been occurring for several thousands of years, while evidence suggests the southwestern Oklahoma contact is more recent, beginning within the past century. We quantify plumage and morphology of the two species across both the younger and older hybrid zones and compare the current and historical extent of phenotypic variation in the older Texas contact with that in the younger Oklahoma contact. Variation in plumage between species is similar in the younger and older contacts, while overlap in morphological characters is broader in the older contact. Recently and historically surveyed transects in the older zone have similar cline widths, indicating selection, at least on crest and forehead plumage, has reached equilibrium with dispersal over the time periods involved (comparing both the historically surveyed data from 1955 vs. the recently surveyed data from the 2000s in Texas). In the recently surveyed younger Oklahoma contact, cline width is narrower, indicating potential for expansion if it follows the course of the older contact. This temporal complexity should make this species complex a productive system for future work, using plumage and additional traits such as song and genetics, on the relative influences of both natural and sexual selection on the evolution of reproductive isolation.

Evaluation of Meteorological Base Models for Estimating Hourly Global Solar Radiation in Texas

Building thermal performance and potential solar applications depend on the quality of the solar resource data available. Unfortunately, most of the locations do not account for measured solar radiation data and, as a result, rely on the values from typical meteorological years. Texas, in a similar fashion as other states in the US, does not have an active network for solar radiation data and has a variety of weather conditions that could be integrated into more than three climate zones. Therefore, in order to estimate reliable solar radiation for different locations in Texas, this paper presents the comparison and the adjustment between two models that use the meteorological data available from the National Climatic Data Center (NCDC) of the National Oceanic and Atmospheric Administration (NOAA). The comparison study was based on sixteen solar stations that cover three climate zones in Texas and use hourly solar radiation data that was recorded from 2000 through 2002 and 2010 through 2012.In this study, the estimated and measured hourly global solar radiations were compared to evaluate which model would be most suitable in each location in Texas. The two models that were studied were a modified Cloud-cover Radiation Model (CRM) by Muneer and the model developed by Zhang and Huang. These models are regression type models that use location or site specific coefficients, which have shown a good correlation during the past years between measured global solar radiation and local meteorological parameters. Most of the locations in climate zone 2, in general, fit the Zhang–Huang Model better, whereas the CRM model presents a better correlation for climate zones 3 and 4.

A multi-environment trial analysis shows slight grain yield improvement in Texas commercial maize

Grain yield in maize has increased steadily in the Midwestern United States since the 1930s but trends are not clear for the maize production zones in the southern states, of which Texas is the major producer. The objective of this study was to elucidate trends of maize yields in Texas for the last 11 years and to identify any significant patterns in breeding and testing maize that can be exploited for improvement. A linear mixed model applied to 107 corn performance trials grown involving 11 years and 16 locations in Texas identified that the largest G×E variance for the multi-environment trial (MET) dataset was the three-factor interaction model that included hybrid, location, years and their interactions. Repeatability measures showed that two replicates and two years provided accurate estimates of genetic yield potential. Trial data and a separate analysis of county level yield data corroborated that there are two separate production zones in Texas, the High Plains and the rest of the state. Across these production zones there have been no substantial gains in yield and surprisingly some older commercial hybrids appear to have had better yield potential then what is currently commercially available. Plant height, ear height, plant population and test weight were positively correlated with grain yield with stronger effects observed in the rest of Texas than in the High Plains; lodging was negatively correlated with grain yield while days to silk showed little effect. This suggests separate strategies for additional genetic and trial improvement should be used in the High Plains and the rest of Texas.

Geochronology of Bimodal Alkaline Volcanism in the Balcones Igneous Province, Texas: Implications for Cretaceous Intraplate Magmatism in the Northern Gulf of Mexico Magmatic Zone

Abstract Small‐volume Late Cretaceous monogenetic alkaline volcanism along the southern margin of North America resulted in a broad igneous belt more than 1200 km long from the Trans Pecos region of west Texas to central Mississippi, collectively forming a northern Gulf of Mexico magmatic zone (NGMMZ). The locus of igneous activity is associated with the discontinuity separating Mesoproterozoic cratonic lithosphere and Jurassic transitional lithosphere, a zone approximating the southern margin of Laurentia, the subsurface trend of the Pennsylvanian Ouachita orogenic belt, and the trace of the Miocene Balcones fault zone in Texas. Although previous studies have attempted to determine the ages of igneous activity in the region, few well‐constrained geochronologic data using modern high‐resolution techniques are available. We determined the age of eruption for the Balcones igneous province (BIP), a 400‐km‐long subsegment of the NGMMZ, using modern 40Ar/39Ar and U‐Pb geochronology methods. Our results suggest...

Devices to Implement Short-Term Speed Limits in Texas Work Zones

In Texas, speed limits for short-term (less than 12 consecutive h) work zones are used when workers or equipment are not behind a concrete barrier, work activity is within 15 ft of the pavement edge, or work is actually occurring on the pavement. In these situations, speed limit signs for short-term work zones should be posted and visible to the motorists only when work activity is present and covered or removed when no work activity is present. Covering or removing signs can be a tedious task to complete daily or weekly. In addition, this task may interfere with normal traffic flow and expose workers to traffic hazards. Some contractors choose not to cover or remove signs; others simply forget: thus speed limits for short-term regulatory work zones extend into time periods with no apparent need for a speed limit reduction. New sign technologies may simplify the implementation process speed limits for short-term work zones and could enhance the use of such speed limits in general. However, such technologies have not been used extensively for speed limits in work zones in Texas. Thus, researchers at the Texas Transportation Institute conducted field studies to determine the operational effectiveness of electronic speed limit signs and flexible roll-up speed limit for work zones signs. The researchers recommended the use of both types of signs.

Variable Time Headway Criteria to Improve Reliability of Speed Control System Evaluations

The effectiveness of a particular speed control system depends on how it influences the behavior of those drivers whose speed selection is unaffected by other vehicles around them. A common rule of thumb that can be used to separate these so-called unconstrained or free-flowing vehicles from a traffic stream is to set a time headway threshold (e.g., 5 s) and consider only those vehicles that have headways greater than or equal to the preset threshold. Although this time headway criterion has been widely accepted, there are some problems with its use. In certain cases, motorists keeping longer headways may still be affected, whereas others keeping shorter headways may be unaffected by the vehicle in front of them. This paper identifies potential problems associated with the use of constant headway thresholds and recommends an alternative approach. A methodology that uses variable headway thresholds is presented, and its application is illustrated with speed and headway data collected in a freeway work zone in Texas. The advantage of the proposed variable headway thresholds is that they can account for a number of site-specific variables, such as roadway geometry and traffic and driver characteristics. They are determined from the actual raw data collected at each site and therefore provide a headway threshold more realistic than the constant headway criteria used to separate free-flowing and constrained vehicles in evaluations of speed control measures. Therefore, in many cases, they are expected to improve the reliability of evaluations of speed control systems.

Comparative Design Case Studies of Pavement Performance on Expansive Soils

Vertical movements calculated with the new design method for six case study cross sections in three different climatic zones in Texas were compared with the swelling movement predicted by the potential vertical rise (PVR) method, which has been used by the Texas Department of Transportation. Vertical movements included both swelling and shrinking. A review of assumptions that underlie the PVR method shows that two assumptions are unrealistic because they are not based on sound analytical principle and the three others cannot be supported by subsequent findings on actual Texas pavements or on soils of the United States. Pavement treatments were selected to provide acceptable predicted performance at high levels of reliability, and the vertical movements were calculated both at the edges of pavements and beneath the outer wheel-paths. The case studies were based on a variety of traffic levels, site conditions, and sample testing. The pavement treatments included limestabilized and cement-stabilized layers, ...

Comparative Design Case Studies of Pavement Performance on Expansive Soils

Vertical movements calculated with the new design method for six case study cross sections in three different climatic zones in Texas were compared with the swelling movement predicted by the potential vertical rise (PVR) method, which has been used by the Texas Department of Transportation. Vertical movements included both swelling and shrinking. A review of assumptions that underlie the PVR method shows that two assumptions are unrealistic because they are not based on sound analytical principle and the three others cannot be supported by subsequent findings on actual Texas pavements or on soils of the United States. Pavement treatments were selected to provide acceptable predicted performance at high levels of reliability, and the vertical movements were calculated both at the edges of pavements and beneath the outer wheelpaths. The case studies were based on a variety of traffic levels, site conditions, and sample testing. The pavement treatments included lime-stabilized and cement-stabilized layers, removal and replacement with inert layers, and vertical and horizontal moisture barriers. The results of the case studies showed that the PVR method overpredicts the swelling movement that can be expected with the new method and does not predict shrinkage movement, which is important because that is an indicator of future longitudinal shrinkage cracking along the pavement edge.

Carbaryl Resistance in Mexican Strains of the Southern Cattle Tick (Acari: Ixodidae)

Susceptibility to carbaryl in six Mexican strains of the southern cattle tick, Boophilus microplus (Canestrini), was evaluated with the Food and Agricultural Organization larval packet test. Tick strains from the cattle fever tick quarantine zone in Texas were more susceptible to carbaryl than to coumaphos or diazinon. Compared with the susceptible reference (Gonzalez) strain, Mexican tick strains demonstrated 10.9-59.5-fold resistance to carbaryl. Significant cross-resistance was found between carbaryl and the organophosphate acaricides coumaphos and diazinon. Bioassay results with synergists suggested that metabolic detoxification mechanisms did not play a major role in carbaryl resistance. Resistance to carbaryl was likely conferred by insensitive acetylcholinesterase. The implications of carbaryl resistance in tick eradication and control also are discussed.

Carbaryl Resistance in Mexican Strains of the Southern Cattle Tick (Acari: Ixodidae)

Susceptibility to carbaryl in six Mexican strains of the southern cattle tick, Boophilus microplus (Canestrini), was evaluated with the Food and Agricultural Organization larval packet test. Tick strains from the cattle fever tick quarantine zone in Texas were more susceptible to carbaryl than to coumaphos or diazinon. Compared with the susceptible reference (Gonzalez) strain, Mexican tick strains demonstrated 10.9-59.5-fold resistance to carbaryl. Significant cross-resistance was found between carbaryl and the organophosphate acaricides coumaphos and diazinon. Bioassay results with synergists suggested that metabolic detoxification mechanisms did not play a major role in carbaryl resistance. Resistance to carbaryl was likely conferred by insensitive acetylcholinesterase. The implications of carbaryl resistance in tick eradication and control also are discussed.

SPATIAL AND TEMPORAL CHARACTERISTICS OF EXTREME-HIGH-SUMMER-TEMPERATURE EVENTS IN THE SOUTH-CENTRAL UNITED STATES

This study examines spatial and temporal characteristics of temperatures exceeding 38° C (100° F) in the south-central United States. Events are concentrated in three distinct zones in Texas with minimum frequencies along the coast. Although temporal analysis identifies no apparent region-wide linear trends in event frequencies, the seasonality of these events is found to vary widely across the study area. Explanations for the observed spatial and temporal patterns are offered. Although the relationship between mean and extreme temperatures is known to be strong, precipitation and rain days also were significantly correlated with extreme temperature events. Hence, the precipitation climatology may be important to understand in the assessment of the future of extreme 38° C events in the south-central United States. [Key words: extreme temperature events, spatial climatic variability, south-central United States.]

THE ST. LAWRENCE VALLEY SYSTEM: A NORTH AMERICAN EQUIVALENT OF THE EAST AFRICAN RIFT VALLEY SYSTEM

The St. Lawrence valley system (including the St. Lawrence, Ottawa, and Champlain valleys, and the St. Lawrence or Cabot trough) is coextensive with a well-defined pattern of seismic activity. The valley system is in a region of general updoming, normal faulting, and alkaline igneous activity of a distinctive type. The main phase of tectonic activity probably dates back to Mesozoic time. The above and other evidence presented in this paper indicate the existence of a major rift valley system that may be called the St. Lawrence rift system.The Rough Creek – Kentucky River fault zone, and the normal fault zones in Texas and Oklahoma, and the Lake Superior fault zone probably represent extensions of the St. Lawrence rift system. However, current seismicity indicates that the present tectonic activity is along a straight zone running through lakes Ontario and Erie into the Mississippi embayment. The St. Lawrence rift system may also be connected with the mid-Atlantic rift, in the region of the Azores plateau.The rift hypothesis presented may be useful as a regional guide in the search for niobium-bearing alkaline complexes and diamond-bearing kimberlites.Crustal tension in the St. Lawrence region may be genetically related to the opening of the Atlantic basin as postulated in the hypothesis of continental drift.