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PurposeTo evaluate cardiovascular disease (CVD) risk factors among smokeless tobacco (ST) users. Exclusive ST users were compared to exclusive cigarette smokers and non-tobacco users. DesignCross-sectional study SampleData were used from 16,336 adult males who participated in one of the National Health and Nutrition Examination Surveys (NHANES) from 2003 to 2018. MeasuresBiochemically verified tobacco use, CVD risk factors (hypertension, cholesterol levels, BMI categories), physical activity, cotinine concentration, and sociodemographic variables. AnalysisWeighted analysis of the aggregate data was performed. ST users were compared with cigarette smokers and nontobacco users for their association with CVD risk factors. Associations were examined using univariate and multiple logistic regression with odds ratios (OR) and 95% confidence intervals (CI) reported. ResultsPrevalence of exclusive ST use was 4.4% whereas, exclusive smoking was 22.2%. Among ST users, 36.2% were hypertensive, 24.5% had high cholesterol levels, and most of them were overweight (31.1%) or obese (52.6%). ST users were more likely to have hypertension compared to smokers (aOR = 1.48, 95%CI: 1.12, 1.95) and nontobacco users (aOR = 1.41, 95%CI: 1.09, 1.83) adjusted for other covariates. ST users were twice more likely to be obese than nontobacco users (aOR = 2.18, 95%CI: 1.52, 3.11). ST users had significantly higher cotinine concentration than smokers. ConclusionStudy findings indicate substantial association of ST use among males with hypertension and obesity which are independent risk factors of CVD. 

This paper presents experimental results for the performance effects of different converging- diverging graphite nozzle throat diameters on an in-house developed kerosenenitrous oxide liquid rocket test stand. The project aims to enhance the performance and efficiency of small-scale liquid rocket engines by experimentally investigating the effects of nozzle throat diameter on thrust and specific impulse. By confirming the correlation between nozzle geometry and the experimental data, it provides valuable insight for improving propulsion systems and components used in experimental rocketry such as sounding rockets. This study will evaluate two different nozzle throat diameters under varying propellant pressures and mass flow rates. The liquid rocket test stand consists of an external aluminum casing with a combustion chamber measuring 20” in length with an outer diameter of 76 mm and an internal diameter of 1.66”. The nozzle throat diameter tested will be 58/64” and 60/64”, each with a fixed exit diameter of 1.82”. Experimental results were collected over a range of total mass flow rates using data acquisition systems and analyzed using graphs and trend lines. The results indicate that as the throat diameter increases, the thrust output and specific impulse increase, although the results are inconclusive due to leaks and a back flame during testing, possibly skewing the results. The ablative wear was analyzed based on the nozzle throat size and mass flow rate. The knowledge gained from this study can be used to prevent future accidents for small-scale liquid rocket engine test stands and verify if the trends seen will be applicable to different nozzle materials and find the optimum nozzle throat diameter. 

Background: Little is known about the demographic and health correlates of secondhand cannabis smoke (SHCS) exposure, despite increased availability and use of cannabis across the U.S. This study examined the prevalence and correlates of SHCS exposure in a sample of N=5,410 adults living in Oklahoma and the association of SHCS exposure with self-reported respiratory problems. Methods: Data were from a repeated cross-sectional online survey of adults ages 18 and older who completed measurements of past 30-day SHCS exposure in the respondent’s home, in a vehicle, and/or in an indoor setting; harm perceptions of SHCS exposure; frequency of current respiratory symptoms; past 30-day use of cannabis, alcohol, and cigarettes Results: Almost half (42 %) reported past 30-day SHCS exposure. In bivariate tests, those exposed were male, younger, non- Hispanic (NH) black or Hispanic, reported lower educational and financial attainment, had lower harm perceptions of SHCS exposure, endorsed more respiratory symptoms, and reported past 30-day cannabis and cigarette use (all p’s < 0.01). In an adjusted regression model, young adulthood (ages 18–24), NH black race (vs NH White), and past 30 -day cigarette smoking and cannabis use emerged as the strongest correlates of SHCS exposure. In interaction models, respiratory symptoms were highest among those reporting past 30-day SHCS exposure and past 30-day cannabis use. Conclusion: SHCS exposure is common and associated with more frequent respiratory symptoms, particularly among cannabis users. Those exposed were more socially and economically vulnerable. 

Copyright © Notice: Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) SONORAN HERPETOLOGIST 37 (3) 2024 139 Introduction The Common Checkered Whiptail (Aspidoscelis tesselatus; Say, 1823) has the most extensive natural geographic distribution among the eight diploid parthenogenetic species recognized in that genus [i.e., A. cozumela (Gadow, 1906), A. maslini (Fritts, 1969), and A. rodecki (McCoy and Maslin, 1962) in the A. cozumela species group; A. laredoensis (McKinney et al., 1973) and A. preopatae (Barley et al., 2021) in the A. sexlineatus group; A. dixoni (Scudday, 1973), A. neomexicanus (Lowe and Zweifel, 1952), and A. tesselatus (Say in James, 1823) in the A. tesselatus group]. The adaptability of A. tesselatus will become even more apparent in a forthcoming report by other scientists on its introduction to and establishment in habitats in California a great distance west of its natural geographic distribution area. Although Zweifel (1965) categorized the extensive color pattern variation in Cnemidophorus = Aspidoscelis tesselatus by recognition of informal pattern classes A, B, C, D, E, and F, subsequent studies have recognized A and B as belonging to the triploid parthenogenetic species Cnemidophorus = Aspidoscelis neotesselatus (Walker, Cordes, and Taylor, 1997) described by Walker et al. (1997) from southeastern Colorado and F as belonging to the diploid parthenogenetic species Cnemidophorus = Aspidoscelis dixoni (Scudday, 1973) described by Scudday (1973) from Hidalgo County, New Mexico, and arrays in Presidio County, Texas. These taxonomic reallocations of some of the pattern classes recognized by Zweifel (1965) to different species reduced the known distribution area of what we currently recognize as A. tesselatus by relatively small areas in Colorado, New Mexico, and Texas, USA. Walker et al. (1994), Walker et al. (1997), Cordes and Walker (2006), and Cole et al. (2007) recognized the arrays (we reserve the term population for species with males and females) of lizards in a small area of Hidalgo County, New Mexico, USA, as pattern class C of A. dixoni, and restricted pattern classes A and B of that species to relatively small areas in Presidio County, Texas. Two of us (JEC and JMW) have found one or more arrays of pattern classes C, D, and E of diploid A. tesselatus to be easily located, abundant, and readily observable at close range in a variety of habitats in parts of Colorado, New Mexico, and Texas, and Chihuahua state, México, as also indicated by Zweifel (1965), Taylor et al. (1996, 2005), Walker et al. (1997), and Taylor (2021). The only exception to the preceding statement pertains to the small geographic area of occurrence of A. tesselatus in Oklahoma, specifically in Cimarron County, which is the westernmost extension of the panhandle of the state. In fact, all the whiptail lizard specialists coauthoring this report (i.e., MAP, JEC, and JMW) have felt the sting of disappointment during repeated attempts to locate and study this species in the state! The total number of A. tesselatus pattern class C lizards observed during the many individual visits to Cimarron County by members of that group was one adult by JEC on 31 July 2015. The purpose of this report is to review what little is known about A. tesselatus in the state of Oklahoma and to document its current presence in the state through a series of recent observations made of this species in Cimarron County, Oklahoma. 

Coxiella burnetii is an obligate intracellular bacterium that lives in a modified lysosome termed the Coxiella containing vacuole (CCV). C. burnetii is the causative agent of the zoonotic illness Q Fever, which primarily infects ruminant livestock and can spread to humans via inhalation. Acute Q fever is characterized by a flu like illness, while chronic disease is associated with more severe symptoms including endocarditis and chronic fatigue syndrome. C. burnetii has a biphasic life cycle consisting of a small cell variant (SCV) and large cell variant (LCV). The SCV is environmentally stable and can cause infection via inhalation of 1 - 10 infectious particles. Once taken up by the host cell, C. burnetii must manipulate the signaling pathways of the host cell to form the CCV where it switches to the LCV, the metabolic and replicative form of the bacterium. It primarily accomplishes this goal by utilizing a Type IV B Secretion System (T4BSS), which is unique to C. burnetii and Legionella pneumophila. The T4BSS, along with some other secretion mechanisms, secretes effector proteins into the host cell. These proteins then interfere with or modulate the host cell to recruit vacuoles, evade detection by the immune system, and prevent the host cell from initiating apoptosis. After about 6 days, the LCV will convert to SCV and then initiate host cell lysis to spread infection. This review looked at many eukaryotic cells signaling pathways and the interactions between C. burnetii and host proteins. These interactions are responsible for the modulation of host cell pathways necessary for CCV formation and C. burnetii survival. Understanding these interactions better will help with future treatments for C. burnetii infection. Further discoveries in these interactions are crucial for the future of C. burnetii research. 

Open dumping and burning of solid waste are widely practiced in underserved communities lacking access to solid waste management facilities; however, the generation of microplastics from these sites has been overlooked. We report elevated concentrations of microplastics (MPs) in soil of three solid waste open dump and burn sites: a single-family site in Tuttle, Oklahoma, USA, and two community-wide sites in Crow Agency and Lodge Grass, Montana, USA. We extracted, quantified, and characterized MPs from two soil depths (0-9 cm and 9-18 cm). The abundance of particles found at the three sites (35,000 to 69,200 particles kg-1 soil) equals or exceeds reported concentrations from currently understood sources of MPs including biosolids application and other agricultural practices. Attenuated total reflectance Fourier transformed infrared (ATR-FTIR) identified polyethylene as the dominant polymer across all sites (46.2%-84.8%). We also detected rayon (≤11.5%), polystyrene (up to 11.5%), polyethylene terephthalate (≤5.1), polyvinyl chloride (≤4.4%), polyester (≤3.1), and acrylic (≤2.2%). Burned MPs accounted for 76.3 to 96.9% of the MPs found in both community wide dumping sites. These results indicate that solid waste dumping and burning activities are a major source of thermally oxidized MPs for the surrounding terrestrial environment with potential to negatively affect underserved communities.