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Ionic liquid materials are viable candidates as a heat transfer fluid (HTF) in a wide range of applications, notably within concentrated solar power (CSP) technology and molten salt reactors (MSRs). For next-generation CSP and MSR technologies that strive for higher power generation efficiency, a HTF with wide liquid phase range and energy storage capabilities is crucial. Studies have shown that eutectic chloride salts exhibit thermal stability at high temperatures, high heat storage capacity, and are less expensive than nitrate and carbonate salts. However, the experimental data needed to fully evaluate the potential of eutectic chloride salts as a HTF contender are scarce and entail large uncertainties. Considering the high cost and potential hazards associated with the experimental methods used to determine the properties of ionic liquids, molecular modeling can be used as a viable alternative resource. In this study, the eutectic ternary chloride salt MgCl2–NaCl–KCl is modeled using ab-initio molecular dynamics simulations (AIMDs) in the liquid phase. Using the simulated data, the thermophysical and transport properties of eutectic chloride salt can be calculated: density, viscosity, heat capacity, diffusion coefficient, and ionic conductivity. For an initial model validation, experimental pair-distribution function data were obtained from X-ray total scattering techniques and compared to the theoretical pair-distribution function. Additionally, theoretical viscosity values are compared to experimental viscosity values for a similar system. The results provide a starting foundation for a MgCl2–NaCl–KCl model that can be extended to predict other fundamental properties.

Objectives Our objective was to evaluate the trend and to assess the impact of maternal region of residence in Western New York (WNY), on severe neonatal opioid withdrawal syndrome (NOWS).Study design Term infants' born at gestational age greater than or equal to 37 weeks with severe NOWS, defined as withdrawal resulting in the receipt of pharmacologic therapy from WNY admitted to our neonatal intensive care unit (NICU) from January 1, 2008 to December 31, 2016, were included. Severe NOWS admissions to our NICU from the following five regions were controlled with birth and insurance data: (1) Urban North, (2) Erie Coastal, (3) Niagara Frontier, (4) Southern Tier, and (5) Urban South.Results "Urban South" residence was associated with an increased risk of severe NOWS (adjusted odds ratio = 1.8, 97.5% confidence interval: 1.1-2.9). The trend in admission for severe NOWS doubled between 2008 to 2010 and 2014 to 2016 (p = 0.01). More infants born to maternal nonprescribed opioid users were placed in foster care at discharge (36.5 vs. 1.9%, p

Ionic liquid materials are viable candidates as a heat transfer fluid (HTF) in a wide range of applications, notably within concentrated solar power (CSP) technology and molten salt reactors (MSRs). For next-generation CSP and MSR technologies that strive for higher power generation efficiency, a HTF with wide liquid phase range and energy storage capabilities is crucial. Studies have shown that eutectic chloride salts exhibit thermal stability at high temperatures, high heat storage capacity, and are less expensive than nitrate and carbonate salts. However, the experimental data needed to fully evaluate the potential of eutectic chloride salts as a HTF contender are scarce and entail large uncertainties. Considering the high cost and potential hazards associated with the experimental methods used to determine the properties of ionic liquids, molecular modeling can be used as a viable alternative resource. In this study, the eutectic ternary chloride salt MgCl2-NaCl-KCl is modeled using ab-initio molecular dynamics simulations (AIMDs) in the liquid phase. Using the simulated data, the thermophysical and transport properties of eutectic chloride salt can be calculated: density, viscosity, heat capacity, diffusion coefficient, and ionic conductivity. For an initial model validation, experimental pair-distribution function data were obtained from X-ray total scattering techniques and compared to the theoretical pair-distribution function. Additionally, theoretical viscosity values are compared to experimental viscosity values for a similar system. The results provide a starting foundation for a MgCl2-NaCl-KCl model that can be extended to predict other fundamental properties. [ABSTRACT FROM AUTHOR]

Globally, billions of people burn fuels indoors for cooking and heating, which contributes to millions of chronic illnesses and premature deaths annually. Additionally, residential burning contributes significantly to black carbon emissions, which have the highest global warming impacts after carbon dioxide and methane. In this study, we use Fourier transform infrared spectroscopy (FTIR) to analyze fine-particulate emissions collected on Teflon membrane filters from 15 cookstove types and 5 fuel types. Emissions from three fuel types (charcoal, kerosene, and red oak wood) were found to have enough FTIR spectral response for functional group (FG) analysis. We present distinct spectral profiles for particulate emissions of these three fuel types. We highlight the influential FGs constituting organic carbon (OC) using a multivariate statistical method and show that OC estimates by collocated FTIR and thermal–optical transmittance (TOT) are highly correlated, with a coefficient determination of 82.5 %. As FTIR analysis is fast and non-destructive and provides complementary FG information, the analysis method demonstrated herein can substantially reduce the need for thermal–optical measurements for source emissions. [ABSTRACT FROM AUTHOR]

Herpes zoster (HZ) is a reactivation of dormant varicellazoster virus that most often erupts as painful vesicles in a unilateral dermatomal distribution. A sequela of HZ is postherpetic neuralgia (PHN), which is debilitating and may be persistent. Therefore, vaccination for the prevention of HZ and its sequelae is recommended for adults aged 50 years and older as well as immunocompromised adults. In 2017, the US Food and Drug Administration approved a recombinant DNA vaccine (Shingrix) that is safe to use in immunocompromised individuals and an improvement on the live-attenuated vaccine approved in 2006. This report discusses HZ, PHN, treatment of HZ and PHN, and prevention with vaccines. [ABSTRACT FROM AUTHOR]

Small modular reactors (SMRs) are currently being considered as future investments for commercial entities due to perceived advantages over traditional large-scale power reactors, particularly their considerably lower capital costs. One strategy for lowering the levelized cost of electricity (LCOE) of SMRs is to increase their burnup by utilizing high-assay low-enriched uranium (HALEU) fuels, which range from 5 to 20 weight percent (w/o) of U-235. By increasing fuel enrichment to HALEU levels, with higher specific fuel costs compared to standard enrichment, a plant may achieve an increased capacity factor by extending its fuel cycle and thereby reducing average yearly fuel supply costs. It is expected that the benefits of optimizing fuel enrichment to extend a reactor’s fuel cycle outweigh the added cost due to more expensive fuel. In this paper, the net benefit of extending an SMR’s fuel cycle by enriching uranium fuel to HALEU levels was estimated using 2017 nuclear fuel production market data with NuScale’s 160 MWt SMR design as a case study. It was found that, for NuScale’s design, plant LCOE decreased with increasing cycle length enabled by higher fuel enrichment. It was also observed that doubling cycle time from 24 months to 48 months netted each reactor a 1.23 $/MWh reduction in LCOE. The total savings for a 12-module SMR design were estimated to be around $5,840,000 per year. Therefore, utilizing HALEU fuel in SMRs can vastly improve their economic efficiency.

Here we report an innovative application of chronopotentiometry (CP) and potentiodynamic scan (PD) techniques to the measurement of redox potentials in a molten salt. Commonly, a stable Cl2/Cl− reference electrode is achieved by direct injection of chlorine gas to a graphite electrode, which requires rigorous design and operation for the high-temperature system to be studied. Instead, in situ techniques (CP and PD) were introduced to generate chlorine gas on the working graphite electrode, which then acts as the chlorine gas source. The measurements of formal potential and activity coefficient of AgCl/Ag at different AgCl mole fractions (X = 0.0039 and X = 0.0145) and temperatures (723–823 K) in molten LiCl-KCl salt were carried out using these two techniques. Moreover, these simple methods can be applied to measure the equilibrium potentials, formal potentials and activity coefficients of other metal chlorides in molten chloride salt as well as in other molten salt systems. Keywords: AgCl/Ag reference electrode, Activity coefficient measurement, Chronopotentiometry, Potentiodynamic scan, Molten chlorides

During thermal processes utilized in affixing fluoropolymer coatings dispersion to fibers and fabrics, coating components are vaporized. It is suspected that per- and polyfluoroalkyl substances (PFAS) from the dispersions may undergo chemical transformations at the temperatures used, leading to additional emitted PFAS thermal byproducts. It is important to characterize these emissions to support evaluation of the resulting environmental and health impacts. In this study, a bench-scale system was built to simulate this industrial process via thermal application of dispersions to fiberglass utilizing relevant temperatures and residence times in sequential drying, baking, and sintering steps. Experiments were performed with two commercially available dispersions and a simple model mixture containing a single PFAS (6:2 fluorotelomer alcohol [6:2 FTOH]). Vapor-phase emissions were sampled and characterized by several off-line and real-time mass spectrometry techniques for targeted and nontargeted PFAS. Results indicate that multiple PFAS thermal transformation products and multiple nonhalogenated organic species were emitted from the exit of the high temperature third (sintering) furnace when 6:2 FTOH was the only PFAS present in the aqueous mixture. This finding supports the hypothesis that temperatures typical of these industrial furnaces may also induce chemical transformations within the fluorinated air emissions. Experiments using the two commercial fluoropolymer dispersions indicate air emissions of part-per-million by volume (ppmv) concentrations of heptafluoropropyl-1,2,2,2-tetrafluoroethyl ether (Fluoroether E1), as well as other PFAS at operationally relevant temperatures. We suspect that E1 is a direct thermal decomposition product (via decarboxylation) of 2,3,3,3-tetrafluoro-2-(heptafluoropropoxy)propanoic acid (commonly referred to as HFPO-DA) present in the dispersions. Other thermal decomposition products, including the monomer, tetrafluoroethene, may originate from the PFAS used to stabilize the dispersion or from the polymer particles in suspension. This study represents the first researcher-built coating application simulator to report nontargeted PFAS emission characterization, real-time analyses, and the quantification of 30 volatile target PFAS. Implications: Thermal processes used to affix fluoropolymers to fabrics are believed to be a source of PFAS air emissions. These coating operations are used by many large and small manufacturers and typically do not currently require any air emissions control. This research designed and constructed a bench-scale system that simulates these processes and used several off-line and advanced real-time mass spectroscopy techniques to characterize PFAS air emissions from two commercial fluoropolymer dispersions. Further, as the compositions of commercial dispersions are largely unknown, a model three-component solution containing a single PFAS was used to characterize emissions of multiple PFAS thermal transformation products at operationally relevant conditions. This research shows that fluoropolymer fabric coating facilities can be sources of complex mixtures of PFAS air emissions that include volatile and semivolatile PFAS present in the dispersions, as well as PFAS byproducts formed by the thermal transformation of fluorocarbon and hydrocarbon species present in these dispersions. [ABSTRACT FROM AUTHOR]

Globally, billions of people burn fuels indoors for cooking and heating, which contributes to millions of chronic illnesses and premature deaths annually. Additionally, residential burning contributes significantly to black carbon emissions, which have the highest global warming impacts after carbon dioxide and methane. In this study, we use Fourier transform infrared spectroscopy (FTIR) to analyze fine particulate emissions collected on Teflon membrane filters from fifteen cookstove types and five fuel types. Emissions from three fuel types (charcoal, kerosene, and red oak wood) were found to have enough FTIR spectral response for functional group (FG) analysis. We present distinct spectral profiles for particulate emissions of these three fuel types. We highlight the influential FGs constituting organic carbon (OC) using a multivariate statistical method and show that OC estimates by collocated FTIR and thermal optical transmittance (TOT) are highly correlated, with a coefficient of determination of 82.5%. As FTIR analysis is fast, non-destructive, and provides complementary FG information, the analysis method demonstrated herein can substantially reduce the need for thermal-optical measurements for source emissions. [ABSTRACT FROM AUTHOR]

While a rare ophthalmic pathogen, infections from Exophilia spp. are increasingly identified and have been associated with catastrophic vision loss. In this case report we present a previously undescribed manifestation of the melanin-producing fungus Exophilia Phaeomuriformis to the lower eyelid, establish an effective treatment, and review related cases. Previous cases of ophthalmic E. Phaeomuriformis were confined to the cornea and included iatrogenic tissue trauma. This case shares neither associations however includes a remote SJS history that likely led to changes in conjunctival tissue integrity. Previous cases of Exophilia spp. infecting the eyelid both included surgical source control and adjuvant antibiotic. In this case, topical therapy was deferred due to SJSrelated ocular cicatricial disease. Fortunately, a full resolution was achieved with surgical resection and oral antifungal treatment. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFAS) are persistent environmental pollutants associated with negative health impacts. Assessments of tubing-related measurement bias for volatile PFAS are lacking, as gas-wall interactions with tubing can delay quantification of gas-phase analytes. We use online iodide chemical ionization mass spectrometry measurements to characterize tubing delays for three gas-phase oxygenated PFAS − 4:2 fluorotelomer alcohol (4:2 FTOH), perfluorobutanoic acid (PFBA), and hexafluoropropylene oxide dimer acid (HFPO-DA). Perfluoroalkoxy alkane and high-density polyethylene tubing yielded relatively short absorptive measurement delays, with no clear dependence on tubing temperature or sampled humidity. Sampling through stainless steel tubing led to prolonged measurement delays due to reversible adsorption of PFAS to the tubing surface, with strong dependence on tubing temperature and sample humidification. Silcosteel tubing afforded shorter measurement delays than stainless steel due to diminished surface adsorption of PFAS. Characterizing and mitigating these tubing delays is crucial for reliable quantification of airborne PFAS. Implications: Per- and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants. Many PFAS are sufficiently volatile to exist as airborne pollutants. Measurements and quantification of airborne PFAS can be biased from material-dependent gas-wall interactions with sampling inlet tubing. Thus, characterizing these gas-wall interactions are crucial for reliably investigating emissions, environmental transport, and fates of airborne PFAS. [ABSTRACT FROM AUTHOR]

With the incidence of skin cancer increasing in the United States, the role of dental providers in noting suspicious skin lesions as well as advising patients in proper sun-protective strategies is more important than ever. However, the public conversation about proper sun protection is often laden with misunderstandings and pervasive myths. This article reviews the most common types of skin cancer, elucidates the differences among the types of UV radiation, and offers updated recommendations for proper sunscreen use along with adjunctive sun-protective strategies. [ABSTRACT FROM AUTHOR]

To investigate the role of nonsurgical management in the treatment of orbital cellulitis complicated by subperiosteal abscess (SPA) in adolescent and adult populations. A retrospective cohort study to assess the demographic, clinical, and outcome profiles of adolescent and adult patients with orbital SPA treated nonsurgically versus those who received surgical intervention. Primary outcome measures included hospitalization length and best-corrected visual acuity (BCVA) in the final evaluation. The study comprised 76 patients diagnosed with SPA in the setting of orbital cellulitis. Twelve were stratified into the nonsurgical cohort, while 64 represented the surgical group. Sinusitis was the most prevalent risk factor among both populations, and the rate did not differ significantly. SPA was located medially at a significantly higher rate in the nonsurgical cohort compared with the surgical. No patients in the nonsurgical population had a relative afferent pupillary defect (RAPD) on presentation. The proportion of patients who received adjunctive systemic corticosteroid therapy was comparable in both groups. Hospitalization length was significantly higher in the surgery cohort. BCVA in the final evaluation was favourable in both groups. Sinusitis subgroup analysis including eight nonsurgical patients produced overall consistent results. Findings from the largest study of orbital cellulitis complicated by SPA to date demonstrate a role for nonsurgical management in adolescent and adult patients who present with a medial SPA and/or ophthalmic examination without an RAPD. Among these populations, visual prognosis is favourable whether management includes surgical debridement or not, and surgical intervention may not predict a shorter duration of hospitalization. [ABSTRACT FROM AUTHOR]

Purpose: To demonstrate novel treatments for patients with high juvenile xanthogranuloma (JXG) eyelid lesion burden. Case Report: A 14-year-old girl was referred to the oculoplastic surgery service for management of worsening extensive bilateral eyelid and adnexal lesions in the setting of JXG. The patient underwent intra-lesional steroid injections, serial excisions, and reconstruction with skin grafts. She was subsequently treated with CO2 laser-assisted topical steroid application, which resulted in lesion regression. Conclusion: A novel multimodal approach to treatment of severe periocular JXG, incorporating surgical debulking, skin autograft, CO2 laser, and intra-lesional steroids, can be effective for lesion control. [ABSTRACT FROM AUTHOR]

Thyroid eye disease (TED), an autoimmune inflammatory disorder of the orbit, presents with a potential array of clinical sequelae. The pathophysiology behind TED has been partially characterized in the literature. There remain certain elusive mechanisms welcoming of research advances. Disease presentation can vary, but those that follow a characteristic course start mild and increase in severity before plateauing into an inactive phase. Diagnosis and evaluation include careful physical examination, targeted laboratory work up, appropriate imaging studies, and tailored treatment regimens. Special consideration may apply to certain populations, such as pediatric and pregnant patients. [ABSTRACT FROM AUTHOR]

Direct application of Bayes' theorem to generalized data yields a posterior probability distribution function (PDF) that is a product of a prior PDF of generalized data and a likelihood function, where generalized data consists of model parameters, measured data, and model defect data. The prior PDF of generalized data is defined by prior expectation values and a prior covariance matrix of generalized data that naturally includes covariance between any two components of generalized data. A set of constraints imposed on the posterior expectation values and covariances of generalized data via a given model is formally solved by the method of Lagrange multipliers. Posterior expectation values of the constraints and their covariance matrix are conventionally set to zero, leading to a likelihood function that is a Dirac delta function of the constraining equation. It is shown that setting constraints to values other than zero is analogous to introducing a model defect. Since posterior expectation values of any function of generalized data are integrals of that function over all generalized data weighted by the posterior PDF, all elements of generalized data may be viewed as nuisance parameters marginalized by this integration. One simple form of posterior PDF is obtained when the prior PDF and the likelihood function are normal PDFs. For linear models without a defect this PDF becomes equivalent to constrained least squares (CLS) method, that is, the χ2 minimization method.

Background: A seasonal transmission environment including seasonal variation of snail population density and human-snail contact patterns can affect the dynamics of Schistosoma infection and the success of control interventions. In projecting control outcomes, conventional modeling approaches have often ignored seasonality by using simplified intermediate-host modeling, or by restricting seasonal effects through use of yearly averaging.Methods: We used mathematical analysis and numerical simulation to estimate the impact of seasonality on disease dynamics and control outcomes, and to evaluate whether seasonal averaging or intermediate-host reduction can provide reliable predictions of control outcomes. We also examined whether seasonality could be used as leverage in creation of effective control strategies.Results: We found models that used seasonal averaging could grossly overestimate infection burden and underestimate control outcomes in highly seasonal environments. We showed that proper intraseasonal timing of control measures could make marked improvement on the long-term burden reduction for Schistosoma transmission control, and we identified the optimal timing for each intervention. Seasonal snail control, implemented alone, was less effective than mass drug administration, but could provide additive impact in reaching control and elimination targets.Conclusions: Seasonal variation makes Schistosoma transmission less sustainable and easier to control than predicted by earlier modeling studies. [ABSTRACT FROM AUTHOR]

The [Na.sup.+]:HC[O.sup.-.sub.3] cotransporter NBC1 (SLC4A4, variant A, kidney specific) is located exclusively on the basolateral membrane of epithelial cells, implying that this molecule has acquired specific signals for targeting to the basolateral membrane. A motif with the sequence QQPFLS (positions 1010-1015) in the cytoplasmic tail of NBC1 was recently demonstrated to mediate targeting of NBC1 to the basolateral membrane. Here, we demonstrate that mutating the amino acid F (phenylalanine) or L (leucine) at positions 1013 or 1014 to alanine, respectively, resulted in the retargeting of NBC1 to the apical membrane. Furthermore, mutation of the FL motif to FF showed similar properties as the wild-type; however, mutation of the FL motif to LL showed significant intracellular retention of NBC1. Mutating the amino acids Q-Q-P and S (positions 1010-1011-1012 and 1015) to A-A-A and A, respectively, did not affect the membrane targeting of NBC1. Functional studies in oocytes with microelectrode demonstrated that the apically targeted mutants, as well as basolaterally targeted mutants, are all functional. We propose that the FL motif in the COOH-terminal tail of NBC1 is essential for the targeting of NBC1 to the basolateral membrane but is distinct from the membrane-targeting di-leucine motif identified in other membrane proteins. basolateral membrane; apical membrane; acid-base regulation; kidney; transmembrane domain