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Now showing 1 - 20 of 3826
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    Cancer Cell Targeting Via Selective Transferrin Receptor Labeling Using Protein-Derived Carbon Dots
    (2024) Strickland, Sara (TTU); Jorns, Mychele (TTU); Fourroux, Luke (TTU); Heyd, Lindsey (TTU); Pappas, Dimitri (TTU)
    Carbon dot (CD) nanoparticles offer tremendous advantages as fluorescent probes in bioimaging and biosensing; however, they lack specific affinity for biomolecules, limiting their practical applications in selective targeting. Nanoparticles with intrinsic affinity for a target have applications in imaging, cytometry, therapeutics, etc. Toward that end, we report the transferrin receptor (CD71) targeting CDs, synthesized for the first time. The formation of these particles is truly groundbreaking, as direct tuning of nanoparticle affinity was achieved by simple and careful precursor selection of a protein, which has the targeting characteristic of interest. We hypothesized that the retention of the original protein’s peptides on the nanoparticle surface provides the CDs with some of the function of the precursor protein, enabling selective binding to the protein’s receptor. This was confirmed with FTIR (Fourier transform infrared) data and subsequent affinity-based cell assays. These transferrin (Tf)-derived CDs have been shown to possess an affinity for CD71, a cancer biomarker that is ubiquitously expressed in nearly every cancer cell line due to its central role mediating the uptake of cellular iron. The CDs were tested using the human leukemia cell line HL60 and demonstrated the selective targeting of CD71 and specific triggering of transferrin-mediated endocytosis via clathrin-coated pits. The particle characterization results reflect a carbon-based nanoparticle with bright violet fluorescence and 7.9% quantum yield in aqueous solution. These unpresented CDs proved to retain the functional properties of the precursor protein. Indicating that this process can be repeated for other disease biomarkers for applications ranging from biosensing and diagnostic bioimaging to targeted therapeutics.
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    Who Shot the Bullet? Projectile Composition Characterization as an Evolutionary Method for Enhancement of Ballistics Evidence Analysis
    (2023) Newland, Ashley (TTU); Banks, Emilynn (TTU); Halámek, Jan (TTU)
    Toolmark and Firearm examiners’ opinions have fallen under scrutiny as inadmissible ballistics evidence has led to the possibility of wrongful convictions and cold cases that could have been solved with the presence of a physical bullet, casing, and/or weapon at the crime scene. This research provides a solution for subjective-based conclusions and the absence of physical evidence altogether. Analysis of bullet material using Atomic Absorption Spectroscopy (AAS) has distinguished bullet composition between manufacturers from a surface scratch. This provides proof of concept that, when a bullet strikes a surface, metal deposits can be extracted and analyzed to corroborate microscopy techniques that currently violate Daubert criteria. Further studies could also provide results to distinguish barrel manufacturers from fired bullets and casings. This novel method of analysis can pave the way for crime scene collection procedures in the absence of physical evidence and provide an increase in scientific value to the expert’s conclusions.
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    Enhanced phenylpropanoid metabolism underlies resistance to Fusarium oxysporum f. sp. vasinfectum race 4 infection in the cotton cultivar Pima-S6 (Gossypium barbadense L.)
    (2023) Ojeda-Rivera, Jonathan Odilón (TTU); Ulloa, Mauricio; Pérez-Zavala, Francisco G. (TTU); Nájera-González, Héctor Rogelio (TTU); Roberts, Philip A.; Yong-Villalobos, Lenin (TTU); Yadav, Himanshu (TTU); Chávez Montes, Ricardo A. (TTU); Herrera-Estrella, Luis (TTU); Lopez-Arredondo, Damar (TTU)
    Introduction: Fusarium oxysporum f. sp. vasinfectum (FOV) race 4 (FOV4) is a highly pathogenic soil-borne fungus responsible for Fusarium wilt in cotton (Gossypium spp.) and represents a continuing threat to cotton production in the southwest states of the United States, including California, New Mexico, and Texas. Pima (G. barbadense L.) cotton, which is highly valued for its fiber quality, has been shown to be more susceptible to this pathogen than Upland (G. hirsutum L.) cotton. Still, some Pima cultivars present resistance to FOV4 infection. Methods: To gain insights into the FOV4-resistance mechanism, we performed comparative transcriptional and metabolomic analyses between FOV4-susceptible and FOV4-resistant Pima cotton entries. FOV4-resistant Pima-S6 and FOV4-susceptible Pima S-7 and Pima 3-79 cotton plants were infected with FOV4 in the greenhouse, and the roots harvested 11 days post-infection for further analysis. Results: We found that an enhanced root phenylpropanoid metabolism in the resistant Pima-S6 cultivar determines FOV4-resistance. Gene-ontology enrichment of phenylpropanoid biosynthesis and metabolism categories correlated with the accumulation of secondary metabolites in Pima-S6 roots. Specifically, we found esculetin, a coumarin, an inhibitor of Fusarium’s growth, accumulated in the roots of Pima-S6 even under non-infected conditions. Genes related to the phenylpropanoid biosynthesis and metabolism, including phenylalanine ammonia-lyase 2 (PAL2) and pleiotropic drug resistance 12 (PDR12) transporter, were found to be upregulated in Pima-S6 roots. Discussion: Our results highlight an essential role for the phenylpropanoid synthesis pathway in FOV4 resistance in Pima-S6 cotton. These genes represent attractive research prospects for FOV4-disease resistance and breeding approaches of other cotton cultivars of economic relevance.
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    Renewable energy resource assessment for rural electrification: a case study in Nepal
    (2023) Sedai, Ashish (TTU); Dhakal, Rabin; Koirala, Pranik; Gautam, Shishir; Pokhrel, Rajat; Lohani, Sunil Prasad; Moussa, Hanna (TTU); Pol, Suhas (TTU)
    Renewable energy could mitigate remote area energy crises through rural electrification. Karnali province, one of the seven federal provinces of Nepal, is such a remote location and is most deprived in terms of electricity access. Around 67% of the population of the Karnali province is not connected to the national grid electricity supply. High altitude, mountainous topography makes it difficult to provide grid access to the region. This study summarizes the current electricity access status in Nepal and Karnali province specifically. The paper discusses the energy, economic and environmental (3E) analysis of different renewable energy resources like solar and wind energy for the grid-isolated region in Mugu and Jumla district of Karnali province. The study investigates the feasibility of a 200-kW solar power plant installation in Gamghadi, the capital of Mugu district and a 100-kW wind power plant installation in Tila village, Jumla district. The study suggests whether a similar installation of the distributed energy plant is a solution to mitigate the energy crisis problem in the high Himalayas regions, like Karnali province of Nepal. Based on the high-level resource assessment, the study estimates an investment cost ranging from 7 to 9 million USD would be necessary for the installation of such distributed solar PV and wind turbines.
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    The Narrative Identity of European Cities in Contemporary Literature
    (2023) Novak, Sonja; Mehan, Asma (TTU); Çirakli, Mustafa Zeki; Quinteiro, Sílvia
    This volume aimed to highlight narrative identities of European cities or city neighbourhoods that have been overlooked, such as mid-sized cities. These cities are neither small towns nor metropolises, cities that are now unveiling their appeal or specificity. The present special issue thus covers a range of representations of cities. The articles investigate more systematically how different texts deal with various cities from different experiential and fictional perspectives. The issue covers the geographical scope across Europe, from east to west or vice versa, as well as a range of different works of national literature(s), but with a clear emphasis on mid-sized European cities that have until now been deemed as lesser-known, secondary, peripheral, 'other' cities that are in the focus of the research of the COST project Writing Urban Places. New Narratives of the European City, within which this journal issue is being published.
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    Photon-rejection power of the Light Dark Matter eXperiment in an 8 GeV beam
    (2023) Åkesson, Torsten; Bravo, Cameron; Brennan, Liam; Bryngemark, Lene Kristian; Butti, Pierfrancesco; Dukes, E. Craig; Dutta, Valentina; Echenard, Bertrand; Eichlersmith, Thomas; Eisch, Jonathan; Elén, Einar; Ehrlich, Ralf; Froemming, Cooper; Furmanski, Andrew; Gogate, Niramay (TTU); Grieco, Chiara; Group, Craig; Herde, Hannah; Herwig, Christian; Hitlin, David G.; Horoho, Tyler; Incandela, Joseph; Ketchum, Wesley; Krnjaic, Gordan; Li, Amina; Mans, Jeremiah; Masterson, Phillip; Middleton, Sophie; Moreno, Omar; Mullier, Geoffrey; Muse, Joseph; Nelson, Timothy; O’Dwyer, Rory; Östman, Leo; Oyang, James; Pascadlo, Jessica; Pöttgen, Ruth; Sarmiento, Luis G.; Schuster, Philip; Solt, Matthew; Suarez, Cristina Mantilla; Tompkins, Lauren; Toro, Natalia; Tran, Nhan; Wallin, Erik; Whitbeck, Andrew (TTU); Zhang, Danyi
    The Light Dark Matter eXperiment (LDMX) is an electron-beam fixed-target experiment designed to achieve comprehensive model independent sensitivity to dark matter particles in the sub-GeV mass region. An upgrade to the LCLS-II accelerator will increase the beam energy available to LDMX from 4 to 8 GeV. Using detailed GEANT4-based simulations, we investigate the effect of the increased beam energy on the capabilities to separate signal and background, and demonstrate that the veto methodology developed for 4 GeV successfully rejects photon-induced backgrounds for at least 2 × 1014 electrons on target at 8 GeV. [Figure not available: see fulltext.]
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    (2023) Arias, V. Santiago; Punyanunt-Carter, Narissra Maria (TTU)
    Tinder is one of the most popular dating apps for heterosexual people/people seeking partners different from their own sex. In consequence, Tinder for some analysts the app has a reputation of being a hook-up app, albeit for other scholars, the app is simply a mediated venue for romantic acquaintanceship. In order to contribute on the discussion of the competing debate about Tinder and online dating in general, this study surveyed 278 participants regarding their Tinder usage, relationship expectations, and communication motives for using Tinder. Current Tinder users reported less intent to marry and more negative attitudes about marriage. Findings also revealed that men and women use the Tinder differently in terms of their communication motives. Specifically, men are more likely than women to use Tinder for the motives of affection, control, and escape. Older adults report using the Tinder significantly more for the motive of pleasure compared to college aged adults.
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    Palladium-Catalyzed β-C(sp3)–H Bond Arylation of Tertiary Aldehydes Facilitated by 2-Pyridone Ligands
    (2024) Xu, Ziting; Li, Zhi; Liu, Chong (TTU); Yang, Ke; Ge, Haibo (TTU)
    2-Pyridone ligand-facilitated palladium-catalyzed direct C–H bond functionalization via the transient directing group strategy has become an attractive topic. Here, we report a Pd-catalyzed direct β-C(sp3)–H arylation reaction of tertiary aliphatic aldehydes by using an α-amino acid as a transient directing group in combination with a 2-pyridone ligand.
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    Anti-Inflammatory Mechanisms of Curcumin and Its Metabolites in White Adipose Tissue and Cultured Adipocytes
    (2024) Islam, Tariful (TTU); Scoggin, Shane (TTU); Gong, Xiaoxia (TTU); Zabet-Moghaddam, Masoud (TTU); Kalupahana, Nishan S. (TTU); Moustaid-Moussa, Naima (TTU)
    The plant-derived polyphenol curcumin alleviates the inflammatory and metabolic effects of obesity, in part, by reducing adipose tissue inflammation. We hypothesized that the benefits of curcumin supplementation on diet-induced obesity and systemic inflammation in mice occur through downregulation of white adipose tissue (WAT) inflammation. The hypothesis was tested in adipose tissue from high-fat diet-induced obese mice supplemented with or without curcumin and in 3T3-L1 adipocytes treated with or without curcumin. Male B6 mice were fed a high-fat diet (HFD, 45% kcal fat) with or without 0.4% (w/w) curcumin supplementation (HFC). Metabolic changes in these mice have been previously reported. Here, we determined the serum levels of the curcumin metabolites tetrahydrocurcumin (THC) and curcumin-O-glucuronide (COG) using mass spectrometry. Moreover, we determined interleukin 6 (IL-6) levels and proteomic changes in LPS-stimulated 3T3-L1 adipocytes treated with or without curcumin by using immunoassays and mass spectrometry, respectively, to gain further insight into any altered processes. We detected both curcumin metabolites, THC and COG, in serum samples from the curcumin-fed mice. Both curcumin and its metabolites reduced LPS-induced adipocyte IL-6 secretion and mRNA levels. Proteomic analyses indicated that curcumin upregulated EIF2 and mTOR signaling pathways. Overall, curcumin exerted anti-inflammatory effects in adipocytes, in part by reducing IL-6, and these effects may be linked to the upregulation of the mTOR signaling pathway, warranting additional mechanistic studies on the effects of curcumin and its metabolites on metabolic health.
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    Systems Engineering Transformation: Transdisciplinary Endeavor
    (2024) Ford, Lynndee; Ertas, A.
    System Engineering (SE) solves the most complex problems bringing together societal issues, theoretical engineering, and transformation of theory into products and services to better mankind and reduce suffering. The research of this paper utilizes transdisciplinary engineering to develop a SE methodology for the concept stage permitting proposal generation accuracy and expediency to provide solutions to counter regional aggressive threats. Today’s world stage is witnessing superpower dominance over neighboring less military-capable nations. The societal impact goes beyond the borders of conflict and affects the world’s global market. In the deterrence of dominance, the United States’ posture is providing weapon systems to the victim in our increasingly unstable geopolitical environment. The US has many reasons to make this technology available to other nations; just as it has many reasons to constrain proliferation. The United States Government is energizing the U.S. defense industry to provide the needed weapon systems following US prescribed acquisition methods. The sale of US weapon systems to International Customers is through a US defense contractor implementing a specialized acquisition model specific for international customers acquiring exportable defense articles. These constraints in the form of export regulations, critical to this paper, are essential to account for early in the concept development. The added complexity to concept development in international defense is that in addition to the usual, “what capabilities does the customer need to accomplish their mission?” and “what are the alternative solutions?” questions, we need to address the fact that US contracts may be required to limit capabilities and/or the technical solution space in opposition to the international customer’s desires. Whereas we normally turn to systems engineering processes to address such complex problems, we have found that the current SE methodology for the concept stage does not address the complexities associated with international sales. The international customers’ need for complex solutions in an expedited time frame emphasizes the prime contractor’s complex and inadequate proposal concept stage. Under U.S. government procurement, the prime contractor shifts a portion of the design phase into the concept phase. This modality requires significant time and funding to fully develop the technical baseline, meanwhile, the international customer requires a solution to react to an immediate threat to their country’s safety. The main objective of this research is to develop a system engineering methodology for the concept stage to effectively understand the technical baseline maturity for proposals specific to International Customers.
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    Self-Administration of a Boar Priming Pheromone Stimulates Puberty in Gilts without Boar Exposure
    (2024) McGlone, John J. (TTU); Duke, Lauren (TTU); Sanchez, Maya (TTU); Garcia, Arlene (TTU)
    Labor is in short supply in animal agriculture. One time-consuming task is estrus detection in gilts. Stimulation with a live boar causes the onset of puberty in young gilts. Typically, a live boar is used to stimulate and identify estrus in the gilts by exposing the gilts to him. Recently, a boar pheromone (BB) was developed to replace the use of a live boar for sows. Additionally, a novel automatic sprayer used as environmental enrichment (EE) by gilts for the self-administration of BB has been developed by this laboratory. A commercial study was conducted to determine whether the use of a live boar could be replaced with a simple EE sprayer, allowing gilts to self-administer BB. Our objective was to determine whether the number and percentage of gilts in estrus obtained using live boars was comparable to self-administration using an EE sprayer containing BB. A total of 242 gilts were randomly assigned to either a live boar (BOAR) or BB self-administration using the environmental enrichment (EE) sprayer. Gilts began simultaneous exposure to either the BOAR or the BB when they were about 4–5 months of age and this continued until they were found in estrus or were injured, died, or never cycled about 2 months later. A total of 83.3% of gilts with exposure to BOAR were identified in estrus and bred, while exposure to BB resulted in 92.9% of gilts reaching puberty and being bred (p < 0.05). The days to reach estrus were 11 days longer for gilts exposed to BB than BOAR. Eight percent more gilts were injured by the BOAR than by using BB (and no boar). The use of BB as a priming pheromone could prevent gilt injuries, save labor, and reduce costs for pig farmers while not inhibiting reproductive output.
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    Transdisciplinary Methodology for Refugee Resettlement Process
    (2024) Ertas, Atila; Tate, Derrick
    This paper’s primary goal is to present a novel transdisciplinary (TD) methodology for the resettlement of refugees. Numerous factors, such as budgetary and cost concerns, federal law and policy, administrative difficulties, security screening protocols, education and training, housing and health, crime rate, socioeconomic issues, and many more, can be considered that influence the refugee resettlement process. Refugee resettlement is a complex matter with numerous factors to consider. Using the Interactive Col lective Intel ligent Management (ICIM) Workshop, the working group developed transdisciplinary col lective intel ligence to investigate the issue. The Nominal Group Technique (NGT) was used to develop and clarify a list of issues about the complex issue through the survey. A condensed example of refugee resettlement that has ten TD solutions and six complex issue chal lenges created with ICIM. Using TD integrated tools, TD solutions to create effective administrative processes that wil l significantly affect the chal lenging issues associated with refugee resettlement have been examined.
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    A Simplified Electrical-Based Model for Electroporation Dynamics
    (2024) Loveless, Amanda M.; Wyss, Samuel J.; Milestone, William; Joshi, Ravi P.; Garner, Allen L.
    Calculating pulsed electric field (PEF)-induced pore formation using the Smoluchowski equation (SME) can be computationally expensive, even when reduced to the asymptotic SME (ASME). These issues are exacerbated when incorporating additional physical phenomena, such as membrane temperature gradients or shock waves, or incorporating pore formation into multiscale models starting from an external stimulus at the organism level. This study presents a rapid method for calculating the membrane-level effects of PEFs by incorporating a semi-empirical equation for transmembrane potential (TMP)-dependent membrane conductivity into a single-shell model for calculating the TMP. The TMP calculated using this approach and the ASME agreed well for a range of electric field strengths for various PEF durations and AC frequencies below and above the threshold for pore formation. These results demonstrate the feasibility of rapidly predicting TMP, which is easily measured, during pore formation strictly from electrical properties and dynamics without needing to explicitly calculate pore dynamics, as required when using the SME and ASME.
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    University Campus as a Complex Pedestrian Dynamic Network: A Case Study of Walkability Patterns at Texas Tech University †
    (2024) Salkhi Khasraghi, Gisou (TTU); Volchenkov, Dimitri (TTU); Nejat, Ali; Hernandez, Rodolfo (TTU)
    Statistical mechanics of walks defined on the spatial graphs of the city of Lubbock (10,421 nodes) and the Texas Tech University (TTU) campus pedestrian network (1466 nodes) are used for evaluating structural isolation and the integration of graph nodes, assessing their accessibility and navigability in the graph, and predicting possible graph structural modifications driving the campus evolution. We present the betweenness and closeness maps of the campus, the first passage times to the different campus areas by isotropic and anisotropic random walks, as well as the first passage times under the conditions of traffic noise. We further show the isolation and integration indices of all areas on the campus, as well as their navigability and strive scores, and energy and fugacity scores. The TTU university campus, a large pedestrian zone located close to the historical city center of Lubbock, mediates between the historical city going downhill and its runaway sprawling body.
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    Involuntary Transfer: A Vulnerability Pattern in Smart Contracts
    (2024) Khan, Zulfiqar Ali (TTU); Namin, Akbar Siami (TTU)
    Smart Contracts (SCs) communicate with each other using external calls. Their interactions can be malicious, resulting in the loss of Ether. One can blame the reentrancy attack for this exploitation. Several previous endeavors detected the reentrancy vulnerability by creating testing tools using static analysis like Remix. However, these approaches do not execute the programs; hence, we cannot confirm their results. In this paper, we present TechyTech that detects both reentrancy and tx.origin vulnerabilities using a novel dynamic analysis approach of involuntary transfer (i.e., unintended transfer). Henceforth, we use a tree-based categorization string to distinguish the two vulnerabilities and their variations. Further, our research discusses multiple SC-related issues like the hijacked stack, deployed owner, and non-generation of transaction receipts in connection with reentrant calls, which we could not find in previous work. Using an example, we demonstrate how the actual Ether transfer is greater than the intended due to reentrancy.We acknowledge that due to dynamic analysis, TechyTech may suffer from VMExceptions.
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    Heat of hydration, water sorption and microstructural characteristics of paste and mortar mixtures produced with powder waste glass
    (2024) Nassar, Roz Ud Din; Saeed, Danish; Ghebrab, Tewodros (TTU); Room, Shah; Deifalla, Ahmed; Al Amara, Kadhim
    This paper investigates the effects of powder waste glass (PWG) at 10%, 15%, and 20 wt.% replacement of cement on the flow characteristic, setting time, compressive strength, water sorption, rate of the heat of hydration, cumulative heat of hydration; alkali-silica reaction (ASR), and microstructure characteristics of the resulting paste and mortar mixtures. A total of eight cementitious mixtures including two control mixtures have been investigated in this experimental program to evaluate the effect of PWG on the fresh and hardened state characteristics of paste and mortar mixtures. Test results show that the incorporation of PWG in the cementitious mixtures results in significant enhancement of their microstructure, increase in compressive strength, improvement in moisture barrier characteristics, and considerable reduction in the rate of the heat of hydration and cumulative heat of hydration. Up to 20 wt.% replacement of cement with fine PWG is seen to be innocuous from the standpoint of ASR. Furthermore, the use of PWG in paste results in delaying the initial and final setting times and increases the flow characteristic of the mortar mixture.
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    So how special is special K? A systematic review and meta-analysis of ketamine for PTSD RCTs ¿Entonces qué tan especial es la K? Una revisión sistematizada y metanálisis de la Ketamina para ECAs en el TEPT
    (2024) Borgogna, Nicholas C. (TTU); Owen, Tyler (TTU); Vaughn, Jacob (TTU); Johnson, David A.L. (TTU); Aita, Stephen L.; Hill, Benjamin D.
    Background: PTSD is a significant mental health problem worldwide. Current evidence-based interventions suffer various limitations. Ketamine is a novel agent that is hoped to be incrementally better than extant interventions. Objective: Several randomized control trials (RCTs) of ketamine interventions for PTSD have now been published. We sought to systematically review and meta-analyse results from these trials to evaluate preliminary evidence for ketamine’s incremental benefit above-and-beyond control interventions in PTSD treatment. Results: Omnibus findings from 52 effect sizes extracted across six studies (n = 221) yielded a small advantage for ketamine over control conditions at reducing PTSD symptoms (g = 0.27, 95% CI = 0.03, 0.51). However, bias-correction estimates attenuated this effect (adjusted g = 0.20, 95%, CI = −0.08, 0.48). Bias estimates indicated smaller studies reported larger effect sizes favouring ketamine. The only consistent timepoint assessed across RCTs was 24-hours post-initial infusion. Effects at 24-hours post-initial infusion suggest ketamine has a small relative advantage over controls (g = 0.35, 95% CI = 0.06, 0.64). Post-hoc analyses at 24-hours post-initial infusion indicated that ketamine was significantly better than passive controls (g = 0.44, 95% CI = 0.03, 0.85), but not active controls (g = 0.24, 95% CI = −0.30, 0.78). Comparisons one-week into intervention suggested no meaningful group differences (g = 0.24, 95% CI = 0.00, 0.48). No significant differences were evident for RCTs that examined effects two-weeks post initial infusion (g = 0.17, 95% CI = −0.10, 0.44). Conclusions: Altogether, ketamine-for-PTSD RCTs reveal a nominal initial therapeutic advantage relative to controls. However, bias and heterogeneity appear problematic. While rapid acting effects were observed, all control agents (including saline) also evidenced rapid acting effects. We argue blind penetration to be a serious concern, and that placebo is the likely mechanism behind reported therapeutic effects.
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    Collegiate women’s wrestling body fat percentage and minimum wrestling weight values: time for revisiting minimal body fat percent?
    (2024) Jagim, Andrew R.; Tinsley, Grant M. (TTU); Oppliger, Robert A.; Horswill, Craig A.; Dobbs, Ward C.; Fields, Jennifer B.; Cushard, Cliff; Rademacher, Paul D.; Jones, Margaret T.
    Background: The estimation of body fat percentage (BF%) in wrestling is used to determine the minimum wrestling weight (MWW) and lowest allowable weight class (MWC) in which wrestlers are eligible to compete. A 12% minimum threshold is currently used for women wrestlers, yet a potential increase for safety has been discussed. Because of the novelty of collegiate women’s wrestling, there is a paucity of literature available on the body composition norms of this population. The purpose of this study was to provide a descriptive summary of BF% and MWW values of female wrestlers and how MWW values would change with the use of different BF% thresholds. Methods: Data from the 2022–2023 collegiate season were retrospectively analyzed resulting in a sample of 1,683 collegiate women wrestlers from the National Association of Intercollegiate Athletics (NAIA, n = 868) and the National Collegiate Athletics Association (NCAA, n = 815). All wrestlers completed skinfold assessments for weight certification at the start of the competition season. The skinfold values were used to estimate BF% using the Slaughter skinfold prediction equation. Frequency statistics and descriptive analysis were performed to compute normative MWW and BF% profiles. BF% thresholds of 12% (12MWW) and the BF% value defined as the lowest 5th percentile, which would be considered unusually lean, were used to determine the resulting MWW and MWC for each method. The lowest recorded weight and weight class division throughout the season was also recorded for each wrestler. Results: There was a positively skewed (0.94) and platykurtic (1.86) distribution of MWW values. The median ± interquartile range BF% for all wrestlers was 27.4 ± 10.22%, with 17% BF representing the 5th percentile. Only 354 out of 1,579 (22.4%) wrestlers competed in their lowest allowable weight class, based on the 12MWW. Of these 354 wrestlers, the mean BF% was 21.3 ± 5.2% at weight certification with only n = 17 being at or below 12% body fat and an average weight loss of 11.1 ± 8.8 lbs. from the time of weight certification. Throughout the season, wrestlers competed at weights that were, on average (mean ± SD), 19.4 ± 16.9 lbs. higher than their 12MWW (95% CI: 18.6, 20.2 lbs. p < 0.001; effect size [ES] = 1.1), 13.4 ± 19.0 lbs. higher than the 17MWW (p < 0.001; ES = 0.70), and 8.7 ± 8.3 lbs. lower than their weight at the certification (95% CI: 8.3, 9.1 lbs. p < 0.001; ES = 1.1). Conclusions: Nearly all BF% values were well above the 12% threshold used to determine MWW. Increasing the minimum BF% threshold from 12% to 17% would affect a small percentage of wrestlers, likely reduce the need for excessive weight cutting, and minimize the deleterious health effects of an athlete at such a low BF%.
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    Ultradeep ATCA Imaging of 47 Tucanae Reveals a Central Compact Radio Source
    (2024) Paduano, Alessandro; Bahramian, Arash; Miller-Jones, James C.A.; Kawka, Adela; Galvin, Tim J.; Rivera Sandoval, Liliana; Kamann, Sebastian; Strader, Jay; Chomiuk, Laura; Heinke, Craig O.; Maccarone, Thomas J. (TTU); Dreizler, Stefan
    We present the results of an ultradeep radio continuum survey, containing ∼480 hr of observations, of the Galactic globular cluster 47 Tucanae with the Australia Telescope Compact Array. This comprehensive coverage of the cluster allows us to reach rms noise levels of 1.19 μJy beam−1 at 5.5 GHz, 940 nJy beam−1 at 9 GHz, and 790 nJy beam−1 in a stacked 7.25 GHz image. This is the deepest radio image of a globular cluster and the deepest image ever made with the Australia Telescope Compact Array. We identify ATCA J002405.702-720452.361, a faint (6.3 ± 1.2 μJy at 5.5 GHz, 5.4 ± 0.9 μJy at 9 GHz), flat-spectrum (α = −0.31 ± 0.54) radio source that is positionally coincident with the cluster center and potentially associated with a faint X-ray source. No convincing optical counterpart was identified. We use radio, X-ray, optical, and UV data to show that explanations involving a background active galactic nucleus, a chromospherically active binary, or a binary involving a white dwarf are unlikely. The most plausible explanations are that the source is an undiscovered millisecond pulsar or a weakly accreting black hole. If the X-ray source is associated with the radio source, the fundamental plane of black-hole activity suggests a black hole mass of ∼54-6000 M ⊙, indicating an intermediate-mass black hole or a heavy stellar-mass black hole.
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    Researcher effects on the biological structure and edaphic conditions of field sites and implications for management
    (2024) Rinehart, Shelby A.; Dybiec, Jacob M.; Richardson, Parker; Walker, Janet B.; Peabody, James D. (TTU); Cherry, Julia A.
    Field studies are necessary for understanding natural processes in spite of the human-induced disturbances they cause. While researchers acknowledge these effects, no studies have empirically tested the direct (e.g., harvesting plants) and indirect (i.e., trampling) effects of researcher activities on biological structure and edaphic conditions. We leveraged field studies in Alabama and California to monitor the recovery of tidal marshes following research activities. Researcher effects on animals, plants, and sediment conditions remained prevalent almost one year after the disturbance ended. For instance, trampled plots had 14%–97% lower plant cover than undisturbed plots after >10 months of recovery. Researcher effects also impacted plant composition, leading to increased subordinate species abundance. We encourage field researchers to adopt strategies that reduce their scientific footprints, including reducing field visits, limiting field team size, and considering ways to limit potential environmental impacts during study design.