University of Texas at San Antonio
  • San Antonio, TX, United States
Recent publications
Introduction The effects of firearm sales and legislation on crime and violence are intensely debated, with multiple studies yielding differing results. We hypothesized that increased lawful firearm sales would not be associated with the rates of crime and homicide when studied using a robust statistical method. Methods National and state rates of crime and homicide during 1999-2015 were obtained from the United States Department of Justice and the Centers for Disease Control and Prevention. National Instant Criminal Background Check System background checks were used as a surrogate for lawful firearm sales. A general multiple linear regression model using log event rates was used to assess the effect of firearm sales on crime and homicide rates. Additional modeling was then performed on a state basis using an autoregressive correlation structure with generalized estimating equation estimates for standard errors to adjust for the interdependence of variables year to year within a particular state. Results Nationally, all crime rates except the Centers for Disease Control and Prevention–designated firearm homicides decreased as firearm sales increased over the study period. Using a naive national model, increases in firearm sales were associated with significant decreases in multiple crime categories. However, a more robust analysis using generalized estimating equation estimates on state-level data demonstrated increases in firearms sales were not associated with changes in any crime variables examined. Conclusions Robust analysis does not identify an association between increased lawful firearm sales and rates of crime or homicide. Based on this, it is unclear if efforts to limit lawful firearm sales would have any effect on rates of crime, homicide, or injuries from violence committed with firearms.
COVID-19 imposed significant limitations upon the 2021 U.S. National Resident Matching Program (NRMP), most important of which is the replacement of traditional in-person interviews with a virtual format. To determine the strengths, limitations, and overall utility of virtual interviews (VIs) for residency applicant selection, a 14-question electronic survey was administered to programme directors (PDs) of all American Council for Graduate Medical Education (ACGME)-accredited residency programmes, from December 2020 through March 2021. PDs were asked about their experience with VIs and the ability to assess residency applicants using the virtual format. A total of 1123 PDs (30% response rate) representing 30 different specialities responded to our survey. Compared to in-person interviews, VIs made it more challenging to assess applicants' fit with the programme, emotional intelligence, commitment to speciality, and ability to function as a resident physician. Overall, only 15% of PDs believed that VIs were better than in-person interviews. Once travel restrictions are lifted and in-person interviews are possible, 67% of PDs plan on hosting dual-format residency interviews, while 26% and 5% of PDs will exclusively host in-person interviews and VIs, respectively. This result was significantly different between surgical and non-surgical programmes [35% of surgical PDs suggested they would offer in-person interviews exclusively, compared to 21% of non-surgical PDs, p < 0.0001]. Although proven to be cost and time-efficient, VIs were challenging in evaluating certain qualities of residency applicants. While this study was focused on U.S. residency matching, it provides important insights about the future of VIs in medical recruitment as a whole.
Background Radiology serves in the diagnosis and management of many diseases. Despite its rising importance and use, radiology is not a core component of a lot of medical school curricula. This survey aims to clarify current gaps in the radiological education in Egyptian medical schools. In February–May 2021, 5318 students enrolled in Egyptian medical schools were recruited and given a 20-multiple-choice-question survey assessing their radiology knowledge, radiograph interpretation, and encountered imaging experiences. We measured the objective parameters as a percentage. We conducted descriptive analysis and used Likert scales where values were represented as numerical values. Percentages were graphed afterwards. Results A total of 5318 medical students in Egypt answered our survey. Gender distribution was 45% males and 54% females. The results represented all 7 class years of medical school (six academic years and a final training year). In assessing students’ knowledge of radiology, most students (75%) reported that they received ‘too little’ education, while 20% stated the amount was ‘just right’ and only 4% reported it was ‘too much.’ Sixty-two percent of students stated they were taught radiology through medical imaging lectures. Participants’ future career plans were almost equally distributed. Near half of participants (43%) have not heard about the American College of Radiology Appropriateness Criteria (ACR-AR), while 39% have heard about it but are not familiar with. Conclusions Radiology is a novel underestimated field. Therefore, medical students need more imaging exposure. To accomplish this, attention and efforts should be directed toward undergraduate radiology education to dissolve the gap between radiology and other specialties during clinical practice. A survey answered by medical students can bridge between presence of any current defect in undergraduate radiology teaching and future solutions for this topic.
Abstract Background There is a worldwide deficit in teaching and training in the field of radiology for undergraduate medical students. This educational gap is prominent in many medical schools as most radiology curricula are a part of other specialty trainings, usually provided by non-radiologists. After COVID-19 pandemic, there was an increased trend in online education. However, questions have been raised about the efficacy and acceptance of online education. We developed a course on the principles of radiology and medical imaging basics to target Egyptian medical students. We then assessed the impact of these educational videos through several online surveys. Our "The Principles of Radiology Online Course" was delivered to students at various Egyptian medical schools; it was a prerecorded series composed of nine sessions, and each session followed the sequence of a pre-test, video, and post-test. There was a final survey to assess the overall feedback. Finally, we analyzed the results to give insight onto how teaching radiology through online lectures can help build better physicians. Results Among various medical schools around Egypt, 1396 Egyptian medical students joined this cohort. Cohort population percentage was 56% female and 44% male. Ninety-eight percent of the students agreed that this program increased their understanding of radiology. Eighty-four percent of the students found the platform friendly and easy to use. Seventy-nine percent found these webinars were more convenient compared to in-person education. Statistical significance (p-value
Alzheimer’s disease (AD), a critical neurodegenerative condition, has a wide range of effects on brain activity. Synaptic plasticity and neuronal circuits are the most vulnerable in Alzheimer’s disease, but the exact mechanism is unknown. Incorporating optogenetics into the study of AD has resulted in a significant leap in this field during the last decades, kicking off a revolution in our knowledge of the networks that underpin cognitive functions. In Alzheimer's disease, optogenetics can help to reduce and reverse neural circuit and memory impairments. Here we review how optogenetically driven methods have helped expand our knowledge of Alzheimer's disease, and how optogenetic interventions hint at a future translation into therapeutic possibilities for further utilization in clinical settings. In conclusion, neuroscience has witnessed one of its largest revolutions following the introduction of optogenetics into the field.
Background This study examined the effect of linking small-scale women farmers to markets, referred to as community marketing, and homestead food production extension services in two districts of rural Bangladesh. Method We particularly focused on identifying the relationship between treatment and food security, monthly expenditure patterns, and food production and marketing by adopting a doubly robust method that mediated bias from project site selection and potential misspecification of the postulated outcome or treatment model. Results The main results showed that establishing community marketing sites along with extension services provided women farmers a secured marketing outlet for food production, plausibly associated with a decreased likelihood of a reduction in monthly expenditures on healthcare (12.7 percentage points), child education (19.4 percentage points), and transportation (51.5 percentage points) during the lean season. However, if farmers did not spend extra income generated from marketing on food purchases, it would be difficult to anticipate an improvement in food security. Conclusion Community marketing was devised to link women smallholders to the markets without conflicting with social and cultural norms for which women were responsive, and our research findings supported the claim that they benefited from community marketing participation. Therefore, government, NGO, or other extension providers looking for a culturally appropriate approach to address women farmers’ limited mobility may consider using or modifying community marketing.
Background Many institutions are training clinicians in point-of-care ultrasound (POCUS), but few POCUS skills checklists have been developed and validated. We developed a consensus-based multispecialty POCUS skills checklist with anchoring references for basic cardiac, lung, abdominal, and vascular ultrasound, and peripheral intravenous line (PIV) insertion. Methods A POCUS expert panel of 14 physicians specializing in emergency, critical care, and internal/hospital medicine participated in a modified-Delphi approach to develop a basic POCUS skills checklist by group consensus. Three rounds of voting were conducted, and consensus was defined by ≥ 80% agreement. Items achieving < 80% consensus were discussed and considered for up to two additional rounds of voting. Results Thirteen POCUS experts (93%) completed all three rounds of voting. Cardiac, lung, abdominal, and vascular ultrasound checklists included probe location and control, basic machine setup, image quality and optimization, and identification of anatomical structures. PIV insertion included additional items for needle tip tracking. During the first round of voting, 136 (82%) items achieved consensus, and after revision and revoting, an additional 21 items achieved consensus. A total of 153 (92%) items were included in the final checklist. Conclusions We have developed a consensus-based, multispecialty POCUS checklist to evaluate skills in image acquisition and anatomy identification for basic cardiac, lung, abdominal, and vascular ultrasound, and PIV insertion.
Objective Environmental enrichment is used to treat social, communication, and behavioral deficits and is known to modify the expression of synaptic receptors. We compared the effects of environmental enrichment in the expression of glutamate and endocannabinoid receptors, which are widely expressed in the cerebellar cortex. These two receptors interact to regulate neuronal function and their dysregulation is associated with behavioral changes. We used BTBR + Itpr3tf/J mice, a strain that models behavioral disorders, and C57BL/6 mice for comparison. We studied the effects of genetic background, sex, environmental conditions, and layer of the cerebellar cortex on the expression of each receptor. Results The influence of genetic background and environmental enrichment had the same pattern on glutamate and endocannabinoid receptors in males. In contrast, in females, the effect of environmental enrichment and genetic background were different than the ones obtained for males and were also different between the glutamate and endocannabinoid receptors. Furthermore, an analysis of both receptors from tissue obtained from the same animals show that their expression is correlated in males, but not in females. Our results suggest that environmental enrichment has a receptor dependent and sexual dimorphic effect on the molecular expression of different receptors in the cerebellar cortex.
Health prognosis for power system is considered as a crucial process of condition-based maintenance. In order to solve the problem of large deviation between Hidden Markov Model and actual system health diagnosis, this paper developed an improved Degenerated Hidden Markov Model (DGHMM) with a core of the quasi power relation. First, the model adopts the degradation factors described the process of recession for equipment continuous decreasing in performance. Compared with the conventional exponential accelerated degradation, the quasi power relation accelerated degradation can better describe the process that the performance of the system decreases gradually with the increase of service age. Then, the improved genetic algorithm can replace the conventional EM algorithm for parameters estimation, which overcomes the limitation that the EM algorithm is easy to fall into local optimization. At the same time, in terms of the limitation of life prognosis problem as a result of the Hidden Markov Model must obey exponential distribution, an algorithm named greed approximation based on approximation algorithm and Viterbi algorithm can be proposed to seek maximum probability remaining observation for the purpose of seeking maximum probability dynamically surplus state path to predict the residual life of system. Finally, the proposed method is validated and evaluated with the data set of caterpillar hydraulic pumps. The results show that the method of system health diagnosis and life prognosis based on the improved degraded hidden Markov model is more effective in describing system degeneration and the accuracy of equipment state diagnosis, and is also feasible in the prediction of residual life.
We specify two measures of accounting estimation intensity (AEI) based on the textual analysis of the qualitative disclosures in the critical accounting policies (CAP) section of firms' MD&A. We then examine how these measures relate to financial analyst following and earnings forecast properties. Using a narrow dictionary definition of accounting estimates, we find AEI is positively associated with analyst following. It is also associated with increasing levels of private information in analysts' forecasts and the informativeness of analysts' reports when analysts engage in greater scrutiny of accounting estimates. Using a broader definition of accounting estimates yields a statistically significant relation with the informativeness of analysts' reports. Overall, our results are consistent with AEI stimulating investor demand for analysts' services and increasing the informativeness of these services.
This paper employs order-, trade-, and quote-level data to examine the determinants of order choices and the impacts of order choices on execution quality by various investor types in the Taiwan Stock Exchange. We find marketable-quote orders have a higher degree of price aggressiveness, larger order size, higher trade value, shorter duration, and higher fill rate than behind-the-quote orders. There exists a transient order serial correlation. Different types of investors have their own preferences in order choices, while market microstructure factors, such as transitory volatility, spread, market depth, and trading interval, significantly influence stock traders’ order choices. Findings show that marketable-quote orders tend to perform better in terms of order duration. Moreover, institutional investors spend less time on completing their trades than do individuals, particularly for foreign investors after controlling all other factors.
This study investigates the synergistic strengthening mechanism of graphene oxide (GO), functionalized carbon nanotubes (f-CNT), and nano-silica (NS) triple hybrid-reinforced Portland cement composite. GO was selected as the variable owing to the synergistic effect of GO with both f-CNTs and NS upon dispersion by forming bonds with both nanomaterials. At a low GO dosage (∼0.03 wt% of cement), the bond between GO and NS deteriorated the dispersion in Ca²⁺-rich solution due to the overly attached NS on the GO surface. The highest GO fraction (0.05 wt%) also led to poor dispersion as the excess GO was agglomerated by Ca²⁺ ions. However, an optimal amount of GO (0.04 wt%) significantly improved the dispersion quality. The enhanced dispersion of the triple hybrid positively influenced the hydration degree and mechanical performance of the cement paste (133 % and 156 % for compressive and tensile splitting strength compared to OPC) and the pozzolanic reactivity of NS.
Context: Myelofibrosis and Essential Thrombocythemia Observational STudy (MOST) (NCT02953704) is an ongoing observational study in essential thrombocythemia (ET) or myelofibrosis (MF) patients enrolled in academic (AC) and community (CC) centers throughout the US. Objective: Examine baseline demographics, diagnosis, treatment patterns, and symptom burden in AC versus CC. Design: Longitudinal, prospective, noninterventional. Setting: 24 AC; 82 CC. Patients: High-risk (≥60 years old and/or thromboembolic history) or low-risk ET (receiving ET-directed therapy, excluding aspirin); ≥18 years old, with low-risk or intermediate-1-risk (INT-1-risk) MF (age >65 years). Results: ET cohort (n=1,182): AC (n=273 [17% low-risk; 83% high-risk]); CC (n=909 [12% low-risk; 88% high-risk]). For AC versus CC, mean age (63.7 vs. 69.2 y), race, ethnicity, education level, and employment status were significantly different (P<0.05); 72.0% of AC versus 60.5% of CC patients had >high school education; 43.2% versus 28.2% were employed. Significantly fewer AC patients were White (84.4% vs. 90.3%) and Hispanic/Latino (4.0% vs. 8.6%) (P<0.05). Of high-risk AC versus CC patients, 78.4% versus 81.5% received ET-directed monotherapy (hydroxyurea, 81.5% vs. 82.3%; interferon, 7.3% vs. 0.9%; anagrelide, 5.6% vs. 12.1%). Among low-risk AC versus CC patients, 95.7% versus 93.6% received ET-directed monotherapy (hydroxyurea, 59.1% vs. 84.5%; interferon, 31.8% vs. 1.0%; anagrelide, 2.3% vs. 11.7%). Significantly more AC versus CC patients had ≥1 ET-related, physician-reported symptom and leukopenia (P<0.05). MF cohort (n=203): AC (n=92 [50% low-risk; 50% INT-1-risk]); CC (n=111 [35% low-risk; 65% INT-1-risk]). For AC versus CC, mean age (65.4 vs. 68.5 y), ethnicity, and education level were significantly different; significantly fewer AC than CC patients were Hispanic/Latino (0% vs. 6.3%) (P<0.05). Of low-risk AC versus CC patients, 60.9% versus 53.8% received MF-directed monotherapy (hydroxyurea, 57.1% vs. 52.4%; interferon, 10.7% vs. 4.8%). Among INT-1-risk AC versus CC patients, 50.0% versus 59.7% received MF-directed monotherapy (hydroxyurea, 17.4% vs. 48.8%; interferon, 30.4% vs. 2.3%). Similar percentages of AC versus CC patients had ≥1 MF-related, physician-reported symptom. Conclusions: Real-world data demonstrate similar care between AC and CC. The clinical significance of key differences in demographics, disease features, and treatment history remains unclear. Understanding these will help improve disease management across sites. Older and minority populations in CC may represent a key population for clinical trial recruitment.
Candida auris has emerged globally as a multidrug-resistant pathogen causing outbreaks in health care facilities. Whole genome sequencing (WGS) analysis has identified four major clades, while earlier WGS data from a single Iranian isolate suggested the existence of a potential fifth clade. Here, we confirm the existence of this fifth clade by providing WGS data of another four Iranian isolates. These clade V isolates differed less than 100 single-nucleotide polymorphisms (SNPs) between each other, while they were separated from the other clades by more than 200,000 SNPs. Two of these isolates were resistant to fluconazole and were found to harbor mutations in the TAC1b and ERG11 genes.
Introduction The US Army Burn Center, the only burn center in the Department of Defense provides comprehensive burn care. The Burn Flight Team (BFT) provides specialized burn care during transcontinental evacuation. During Operations Iraqi and Enduring Freedom, burn injuries accounted for approximately 5% of all injuries in military personnel. To augment BFT capacity, US Air Force Critical Care Air Transport Teams (CCATTs) mobilized to transport burn patients. The purpose of this study was to describe critically ill, burn injured patients transported to the US Army Burn Center by BFT or CCATT, to compare and contrast characteristics, evacuation procedures, in-flight treatments, patient injuries/illnesses, and outcomes between the two groups. Materials and Methods We conducted a retrospective cohort study of CCATT and BFT patients, admitted to the burn ICU between January 1, 2001 and September 30, 2018. Patients with total body surface area burned (TBSA) >30% were evacuated by BFT, while CCATT evacuated patients with ≤ 30% TBSA. Results Ninety-seven patients met inclusion criteria for this study. Of these, 40 (41%) were transported by the BFT and 57 (59%) were transported by CCATTs. Compared with patients transported by CCATTs, patients transferred by the BFT had higher median TBSA and full-thickness burn size, higher prevalence of chest, back and groin burns, and higher prevalence of inhalation injury. BFT patients had increased hospital days (62 vs. 37; P = .08), ICU days (29 vs. 12; P = .003) and ventilator days (14 vs. 6; P < .001). TBSA was the only variable significantly associated with ARDS (aOR = 1.04; 95% CI: 1.01, 1.08; P = 0.04), renal failure (aOR = 1.07; 95% CI: 1.03, 1.11; P = .002), and mortality (aOR = 1.08; 95% CI: 1.03, 1.13; P = .001). Conclusions Evacuation by the BFT was associated with increased ICU and ventilator days, increased mortality, and a greater risk for developing renal failure. The severity of injury/TBSA likely accounted for most of these differences.
Oxygen ions are a major constituent of magnetospheric plasma, yet the role of oxygen in processes such as magnetic reconnection continues to be poorly understood. Observations show that significant amounts of energized O⁺ can be present in a magnetotail current sheet (CS). A population of thermal O⁺ only has a relatively minor effect on magnetic reconnection. Despite this, published studies have so far only concentrated on the role of the low‐energy thermal O⁺. We present a study of magnetic reconnection in a thinning CS with energized O⁺ present. Well‐established, three‐species, 2.5D particle‐in‐cell (PIC) kinetic simulations are used. Simulations of thermal H⁺ and thermal O⁺ validate our setup against published results. We then energize a thermal background O⁺ based on published in situ measurements. A range of energization is applied to the background O⁺. We discuss the effects of energized O⁺ on CS thinning and the onset and evolution of magnetic reconnection. The presence of energized O⁺ causes a two‐regime onset response in a thinning CS. As energization increases in the lower‐regime, reconnection develops at a single primary X‐line, increases time‐to‐onset, and suppresses the rate of evolution. As energization continues to increase in the higher‐regime, reconnection develops at multiple X‐lines, forming a stochastic plasmoid chain; decreases time‐to‐onset; and enhances evolution via a plasmoid instability. Energized O⁺ drives a depletion of the background H⁺ around the central CS. As the energization increases, the CS thinning begins to slow and eventually reverses.
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5,360 members
Corey Shepard Sparks
  • Department of Demography
Humberto Herman Lara
  • South Texas Center for Emerging Infectious Diseases
George Perry
  • Department of Neuroscience Developmental and Regenerative Biology (NDRB)
Nicolas Large
  • Department of Physics and Astronomy
One UTSA Circle, 78249, San Antonio, TX, United States
Head of institution
Taylor Eighmy