Superbursts (SBs) are large, seemingly spontaneous activity fluctuations often encountered in high density neural networks in vitro. Little effort has been put forth to define and analyze SBs which are paroxysmal bursting discharges. Through qualitative and quantitative means, I have described specific occurrences of superbursting activity. A complex of paroxysmal bursting has been termed a "superburst episode," and each individual SB is a "superburst event" which is comprises a fine burst structure. Quantitative calculations (employing overall spike summations and coefficient of variation (CV) calculations), reveal three distinct phases. Phase 1 is a "build up" phase of increasingly strong, coordinated bursting with an average of a 17.6% ± 13.7 increase in activity from reference. Phase 2, the "paroxysmal" phase, is comprised of massive coordinated bursting with high frequency spike content. Individual spike activity increases by 52.9% ± 14.6. Phase 3 is a "recovery phase" of lower coordination and an average of a 50.1% ± 35.6 decrease in spike production from reference. SBs can be induced and terminated by physical manipulation of the medium. Using a peristaltic pump with a flow rate of 0.4ml/min, superbursting activity ceases approximately 28.3 min after the introduction of flow. Alternatively, upon cessation of medium flow superbursting …

Factors currently at the forefront of human in vitro fertilization (IVF) that collectively influence treatment success in the form of blastocysts development were investigated during early mammalian embryology with concentration on infertile patients presenting with diminished ovarian reserve or preliminary ovarian failure. A novel experimental technique, Graft Transplant-Embryonic Stem Cells (GT-ESC) was introduced in the mouse model, as the first inclusive approach for embryo selection in IVF treatments resulting in successful graft integration of sibling cells, stage-dependent (day 4) blastocysts. E-Cadherin-catenin bonds play an integral role in trophectoderm cell viability and calcium removal, inducing disruption of cell-to-cell bonds at the blastocyst stage was detrimental to continued blastocyst development. One of the leading methods for embryo selection for uterine transfer in human IVF is application of pre-implantation genetic screening (PGS) methods such as next generation sequencing (NGS). Female patients <35 y do not benefit from this treatment when outcome is measured by presence of fetal heart beats at 10 weeks of gestation. Patients 35-37 y benefit from PGS with no significant difference of outcome based on form of PGS method utilized. Therefore, small nucleotide polymorphism array (snp-array) or targeted-NGS should be selected for this age range to lessen the financial burden …

Postmortem interval (PMI) estimation is a necessary but often difficult task that must completed during a death investigation. The level of difficulty rises as time since death increases, especially with the case of skeletonized remains (long PMI). While challenging, a reliable PMI estimate may be of great importance for investigative direction and cost-savings (e.g. suspect identification, tailoring missing persons searches, non-forensic remains exclusion). Long PMI can be estimated by assessing changes in the organic content of bone (i.e. collagen), which degrades and is lost as the PMI lengthens. Visible-near infrared (VNIR) spectroscopy is one method that can be used for analyzing organic constituents, including proteins, in solid specimens. A 2013 preliminary investigation using a limited number of human cortical bone samples suggested that VNIR spectroscopy could provide a fast, reliable technique for assessing PMI in human skeletal remains. Clear separation was noted between "forensic" and "archaeological" specimen spectra within the near-infrared (NIR) bands. The goal of this research was to develop reliable multivariate classification models that could assign skeletal remains to appropriate PMI classes (e.g. "forensic" and "non-forensic"), based on NIR spectra collected from human cortical bone. Working with a large set of cortical samples (n=341), absorbance spectra were collected …

The anthropogenic alteration of riverine ecosystems has led to declines in the abundance and diversity of freshwater mussels (Bivalvia: Unionoida) worldwide. Central Texas is home to a diverse freshwater mussel fauna including three candidates for federal listing under the Endangered Species Act. Surveys conducted over the last few decades suggest many of the endemic freshwater mussel species in Texas exist in small isolated populations that may be vulnerable to the deleterious effects of genetic diversity loss. Microsatellite primers from two closely related species were used to identify a set of genetic markers that functioned in the Golden Orb (Quadrula aurea). Microsatellite markers were then applied to document the population genetic structure of Q. aurea within and among three connected river drainages in southeastern Texas. Gene flow within existing Q. aurea populations appears high indicating little potential for genetic issues stemming from isolation and inbreeding. Two weakly divergent admixed populations were identified occupying the San Antonio and Guadalupe/San Marcos rivers. Population genetic structure was related to river basin affiliation, but results for environmental factors were unresolved. Current effective population size estimates are large for the Guadalupe/San Marcos drainage and moderately large for the San Antonio drainage and there is no clear …

Cardiovascular activities may increase the brain blood flow improving neuronal activities leading to improved cognition. Consequently, the effects of an acute bout of moderate intensity aerobic exercise on brain hemodynamics and its correlation with cognitive color-word Stroop task performance were tested. The Stroop tasks were congruent (color matches word) and incongruent (color does not match word). Prefrontal (PFC) and motor cortex (MC) blood flow was recorded by fNIRS (functional near-infrared spectroscopy) while the subject was performing the Stroop tasks before and after the 30 minutes of exercise or equivalent time of rest controls (checking for practice effects). Ninety human subjects of age 24± 6, 20 ADHD (attention-deficit hyper-activity disorder), 27 High-BMI (>25), 29 males were recruited. Reaction time ‘RT' decreased (p<0.05) after exercise for both the congruent (12%) and incongruent (10%) Stroop tasks, compared to 8% with practice alone. Accuracy did not change after practice or exercise. HR changes after exercise correlated (p<0.05) with better accuracy and faster RT for the incongruent Stroop task. In general, a metabolic lag occurred in the neuronal deoxy- hemoglobin (Hb) signals behind the systemic oxy-Hb signals. PFC showed the highest effect sizes of Stroop task-responsive systemic hemodynamic changes compared to baseline irrespective of rest …

Through the use of natural history records, published literature, and personal sampling (2011-2016) a total of 454 caddisfly species represented by 24 families and 93 genera were documented from the south-central United States. Two Hydroptilidae species were collected during the 2011-2016 collection efforts that are new to the region: Hydroptilia scheringi and Mayatrichia tuscaloosa. Eightteen species are endemic and 30 are considered species of concern by either federal or state agencies. The majority of each of these groups is Hydroptilidae, or microcaddisflies. Trichoptera community structure, by minimum number of species, was analysed in conjunction with large-scale geographical factors to determine which factor illustrated caddisfly community structure across the region. Physiographic provinces compared to other geographic factors analyzed best-represented caddisfly communities with a minimum of 10 or more species. Statistically, Hydrologic Unit Code 4 (HUC 4) was the most significant geographical factor but low number of samples representing this variable rendered it less representative of caddisfly community structure for the study area.

Acrolein is produced endogenously after traumatic brain injury (TBI) and is considered a primary mechanism for secondary damage occurring after TBI. We are using frontal cortex networks derived from mouse embryos and grown on microelectrode arrays in vitro to monitor the spontaneous activity of networks and the changes that occur after acrolein application. Networks exposed to acrolein exhibit a biphasic response profile. An initial increase in network activity, followed by a decrease to 100% activity loss in applications ≥ 50 µM. In applications below 50 µM, acrolein was not toxic but generated activity instability with coordinated but irregular population busts lasting for up to 6 days. The increase in activity preceding toxicity may be linked to a decrease in free spermine, a free radical scavenger that modulates Na+, K+, Ca+ channels as well as NMDA, Kainate, and AMPA receptors. Action potential wave shape analysis after 20 and 30 µM acrolein application revealed a concentration-dependent 15-33% increase in peak to peak amplitude within minutes after exposure. For the same concentrations of acrolein (50 µM), the time required to reach 100% activity loss (IT100) was longer in serum-free medium than in medium with 5% serum, in which IT100 values were reduced by …

Skeletal muscle satellite cells are important for muscle repairing and muscle mass growth. For a successful muscle regenerative process, satellite cells have to sequentially undergoing different stages of myogenic process, i.e. proliferative state and differentiation state. To support this process, the presence of different circulating factors, such as immune cells, cytokines, and hormones, at the appropriate time course is critical. Among these factors, hormones, such as testosterone, cortisol, and IGF-1, have shown to play an important role in satellite cell proliferation and differentiation. Studies investigated the effect of testosterone on satellite cell using a supraphysiological dose in human or in cell culture demonstrated that testosterone is critical in satellite cell myogenic process. Due to the anabolic effect of testosterone on muscle, studies had been focused on the physiological means to increase the circulating testosterone concentration in the body to maximize the muscle mass growth from resistance exercise. The acute and transient increase in testosterone has shown to be beneficial to muscle mass growth and strength gain; however, this change in physiological testosterone concentration on satellite cell myogenesis is not known. Therefore the purpose of this dissertation is to first determine the effect of acute change in exercise-induced hormones on satellite …

A population survey was conducted on the mosquito species recorded in Denton, Texas for the years of 2005 to 2015. Data used in this project were obtained from an ongoing, long-term surveillance program led by the City of Denton and conducted through the University of North Texas. Research focused on the population dynamics and community structure of mosquitoes collected within urban areas of Denton, Texas in relation to certain environmental variables. A total of 80,837 female mosquitoes were captured and represented 38 species found under the following genera: Aedes, Anopheles, Coquillettidia, Culex, Culiseta, Mansonia, Orthopodomyia, Psorophora, Toxorhynchites, and Uranotaenia. Culex quinquefasciatus was the most abundant species followed by Aedes vexans. Seasonal patterns of the most abundant species revealed high variability throughout the study. Container breeders were most abundant in August and those that breed in floodwaters were most abundant in the months of May and September. Samples were tested for arbovirus presence through the Texas Department of State Health Services in Austin, Texas and multiple pools tested positive for West Nile virus throughout the study. Stepwise multiple regression and Spearman's rank correlation analyses were performed to examine the relationship between the mosquito community and environmental variables. Data revealed that temperature, …

A ballistic pendulum impulse generator was used to impact networks in primary culture growing on microelectrode arrays. This approach has the advantage of imparting pure tangential acceleration insults (50 to 300 g) with simultaneous morphological and electrophysiological multichannel monitoring for days before and after the impact. Action potential (AP) production, network activity patterns, and cell electrode coupling of individual units using AP waveshape templates were quantified. Network adhesion was maintained after tangential impacts up to 300g with minimal loss of pre-selected active units. Time lapse phase contrast microscopy revealed stable nuclei pre-impact, but post impact nuclear rotation in 95% of observations (n= 30). All recording experiments (n=31) showed a repeatable two-phase spike production response profile: recovery to near reference in 1-2 hrs, followed by a slow activity decay to a stable, level plateau approximately 30-40% below reference. Phase 1 consisted of a complex two-step recovery: rapid activity increase to an average 23.6% (range: 11-34%) below reference, forming a level plateau lasting from 5 to 20 min, followed by a climb to within 20% of reference where a second plateau was established for 1 to 2 hrs. Cross correlation profiles showed changes in firing hierarchy after impact, and in spontaneous network …