Search

Vaughna Galvin,1 Dennis J Cheek,2 Yan Zhang,3 Gregory Collins,1 David Gaskin4 1School of Nurse Anesthesia, Texas Christian University, Fort Worth, TX, USA; 2School of Nursing, Texas Christian University, Fort Worth, TX, USA; 3Harris College of Nursing and Health Sciences, Texas Christian University, Fort Worth, TX, USA; 4Republic Pain Specialists, Physicians Centre Hospital, Bryan, TX, USACorrespondence: Vaughna Galvin, School of Nurse Anesthesia, Annie Richardson Bass Building, 2800 West Bowie Street, Suite 3101, Fort Worth, TX, 76109, USA, Tel +1 817-257-7887, Fax +1 817-257-5472, Email V.B.GALVIN@tcu.eduAbstract: One hundred ninety-five patients presenting with post-COVID symptomology, including parosmia and dysgeusia, underwent reversible stellate ganglion blockade. Stellate ganglion blockade was performed at an outpatient facility, and patients were evaluated via survey at seven days post-injection. Of the 195 participants, ages ranged from 18– 69 years of age with the breakdown of sexes being females n = 157 and males n = 38. The most significant finding was a reported improvement in olfaction post-injection in 87.4% of subjects. The effectiveness of this novel treatment for post-COVID is promising and warrants further investigation.Keywords: cervical sympathetic block, COVID, parosmia, dysgeusia, dysautonomia

Solar thermochemical hydrogen generation (STCH) is a promising approach for eco-friendly H2 production, but conventional STCH redox compounds often suffer from thermodynamic and kinetic limitations with limited tunability. Expanding from the nascent high-entropy ceramics field, this study explores a new class of compositionally complex perovskite oxides (La0.8Sr0.2)(Mn(1-x)/3Fe(1-x)/3CoxAl(1-x)/3)O3 for STCH. In situ X-ray diffraction demonstrates the phase stability during redox cycling and in situ X-ray photoelectron spectroscopy shows preferential redox of Co. The extent of reduction increases, but the intrinsic kinetics decreases, with increased Co content. Consequently, (La0.8Sr0.2)(Mn0.2Fe0.2Co0.4Al0.2)O3-{\delta} achieves an optimal balance between the thermodynamics and kinetics properties. The combination of a moderate enthalpy of reduction, high entropy of reduction, and preferable surface oxygen exchange kinetics enables a maximum H2 yield of 395 +- 11 {\mu}mol g-1 in a short 1-hour redox duration. Entropy stabilization expectedly contributes to the structure stability during redox without phase transformation, which enables an exceptional STCH stability for >50 cycles under harsh interrupted conditions. The underlying redox mechanism is further elucidated by the density functional theory based parallel Monte Carlo computation, which represents a new computation paradigm first established here. This study suggests a new class of non-equimolar compositionally complex ceramics for STCH and chemical looping.

In the twelve months leading up to May 2020, over 81,000 people have died due to drug overdoses. Since then, these numbers have been exacerbated by the Covid-19 pandemic, demonstrating an urgent need to develop novel and effective pharmacotherapies for individuals with substance use disorders. Recently, an inflammation associated chemokine receptor, CC Chemokine Receptor 5 (CCR5), has been linked to opioid abuse. We therefore hypothesized that inhibiting CCR5 could reduce opioid-taking in a food versus drug (fentanyl) choice procedure. Adult male Sprague Dawley rats (n=8) were trained to respond for either food (a grain pellet) on one lever, or increasing doses of fentanyl on the alternate lever under a multiple component, fixed ratio (FR) 5, choice procedure. Food was available in each of five components, with component 1 serving as a no drug control, and increasing unit doses of fentanyl (0.32-10 ?g/kg/infusion) available in components 2-5. At baseline, rats responded exclusively on the food lever during the first component, but gradually reallocated their responding towards the fentanyl lever as the unit dose of fentanyl increased, with exclusive choice of fentanyl occurring at the largest dose of fentanyl (10 µg/kg/inf). Pretreatment with the ?-opioid receptor antagonist naloxone (1 and 3.2 mg/kg) significantly reduced choice of fentanyl while increasing both choice of food and trials completed. Pretreatment with haloperidol, a dopamine D2-like receptor antagonist (0.1 and 0.32 mg/kg), did not alter fentanyl choice at doses that did not also reduce trials completed. Pretreatment with Maraviroc (1-10 mg/kg) dose dependently reduced choice of fentanyl while also increasing choice of food and trials completed in later components. These results suggest that Maraviroc may selectively reduce fentanyl's reinforcing effects without affecting behavior maintained by a non-drug reinforcer (food). Future work will seek to determine whether the effects of Maraviroc persist across repeated dosing, and whether the anti-opioid effects of Maraviroc are impacted by opioid dependence and withdrawal.

One of the most controversial and significant of contemporary education reforms has been the teacher accountability movement. From this perspective, low-quality teachers and teaching are a major factor behind inadequate school performance, and a lack of accountability and control in schools is a major factor behind the problem of low-quality teachers and teaching. In turn, to advocates of this reform movement, the solution is to centralize control of schools and hold teachers more accountable. Utilizing a sociology of organizations, occupations and work perspective, the objective of this article was to offer a critique of the teacher accountability perspective and movement. This article draws from, and summarizes, the results of a series of empirical research projects on the levels, distribution and effects of accountability and control in American schools. The argument of the article is that the teacher accountability perspective overlooks some of the most important sources and forms of organizat...

uIn situ exsolution of nanoparticles is widely considered as an efficient and cost-effective method for increasing the number of active sites and consequently the catalytic activity on ceramic anodes in solid oxide fuel cells (SOFCs). In this study, by doping on the A-site of Sr2Fe1.5Mo0.5O6-delta (SF1.5 M), evenly distributed Fe nanoparticles (similar to 100 nm) were exsolved on the La0.5Sr1.5Fe1.5Mo0.5O6- delta (LSFM) surface under a typical anode operating environment (humidified H-2, 800 degrees C). In addition, the exsolution-dissolution reversibility of the exsolved Fe nanoparticles was observed during a redox cycle. Electrical conductivity relaxation (ECR) analysis demonstrated that the surface reaction kinetics on the LSFM anode is enhanced by in situ exsolution. Based on electrochemical impedance spectroscopy (EIS) and distribution of relaxation time (DRT) analysis, the perovskite structure was not damaged by the exsolution or the surface phase transition. During exsolution, the ionic conductivity increased. The higher surface catalytic activity and faster oxygen transportation led to enhanced electrochemical performance.

Perovskite oxide CaBaCo2O5+δ (CBCO) thin films with two divalent alkaline earth metal ions and the transition metal Co ion were prepared by pulsed laser deposition (PLD) system. X-ray diffraction reveals that the as-grown CBCO thin films have good crystallinity of the perovskite structure. Redox electrical properties and chemical sensing behavior on the as-grown CBCO thin films were systematically studied under various chemical environments. The electrical transport property studies indicate that the electrical resistivity increases with increase of temperature under reducing atmosphere and the temperature dependence of resistivity of the CBCO thin film in the oxidation processing above room temperature can be well fitted by small polaron hopping model. The chemical sensing property measurements reveal that the CBCO thin film is very sensitive to oxidizing/reducing environments in the temperature ranges from 620 K to 970 K. Especially, the reduced CBCO thin films with Co2+ and high oxygen vacancy concentration have a superfast oxygen sensing response from 620 to 970 K.

The microstructures of two layered films consisting of 2% Mn doped (Ba,Sr)TiO3 (Mn:BST) and 2% Mn doped Ba (Zr, Ti)O3 (Mn:BZT) layers on a MgO (001) substrate deposited by pulsed laser deposition were studied using X-ray diffraction (XRD), atomic force microscopy (AFM), transmission electron microscopy (TEM), high-resolution TEM and nanoindentation. The films contained four alternating layers of Mn:BST and Mn:BZT either the former or the latter as the first layer. The film deposited with Mn:BST as the first layer has a rough surface, an epitaxial continuous layer structure for the first two layers next to the interface and columnar structures for the top two layers. The first layer has a single oriented crystal structure with an in-plane lattice mismatch of ∼−5.70% and an atomically sharp interface with respect to the substrate. The second layer exhibited twin-induced domain structures. The columnar structures in the top two layers have an average width of ∼70 nm and are tightly attached to their adjacent...

Single-crystalline perovskite LaBaCo2O5.5+δ thin films were grown on a (110) NdGaO3 single-crystal substrate in order to systematically investigate the effect of lattice mismatch on the electrical transport properties in comparison to the films on LaAlO3, SrTiO3, and MgO substrates. Microstructure studies reveal that all of the LaBaCo2O5.5+δ films are of excellent quality with atomically sharp interface structures. The electrical and magnetic transport property studies indicate that the resistivity, magnetoresistance, and magnetic moment of the film are very sensitive to the substrate materials because of the lattice mismatch/interface strain. The Curie temperature, however, is almost independent of the strain imposed by the substrate, probably because of the strong coupling between the nanodomain boundary and interface strain.

Environment-friendly Ferroelectric Mn:BST//Mn:BZT multilayer with additional 2% Mn doping were epitaxially fabricated on (001) MgO substrates by pulsed laser deposition with same thickness but different stacking periodic numbers or each layer thickness. Microstructure studies by X-ray diffraction and transmission electron microscopy indicate that the multilayer is c-axis oriented with good epitaxial nature. The microwave (∼18GHz) dielectric property measurements show that the dielectric loss tangent rapidly decreases with the increase of each layer thickness. The loss tangent can be lowered down to ∼0.043 at ∼18GHz, which suggests that the Mn:BST//Mn:BZT multilayer system has great potential for the development of room temperature microwave elements and related applications.

Highly epitaxial LaBaCo(2)O(5.5+δ) thin films were grown on the vicinal (001) SrTiO(3) substrates with miscut angles of 0.5°, 3.0°, and 5.0° to systemically study strain effect on its physical properties. The electronic transport properties and magnetic behaviors of these films are strongly dependent on the miscut angles. With increasing the miscut angle, the transport property of the film changes from semiconducting to semimetallic, which results most probably from the locally strained domains induced by the surface step terraces. In addition, a very large magnetoresistance (34% at 60 K) was achieved for the 0.5°-miscut film, which is ~30% larger than that for the film grown on the regular (001) SrTiO(3) substrates.

Environmental friendly ferroelectric relaxor Ba(Zr0.2Ti0.8)O3 thin films with an additional 2% Mn dopant were epitaxially fabricated on the (001) LaAlO3 single crystal substrates by pulsed laser deposition. Microstructure characterizations from x-ray diffraction suggest that the films are c-axis oriented with the interface relationship of [101]Mn:BZT//[100]LAO and (001)Mn:BZT //(001)LAO. The microwave dielectric property measurements (13–17.5 GHz) reveal that the films have excellent dielectric properties with large tunability, high dielectric constant, and low dielectric loss, which the average value is 25.9%, 169 and 0.054, respectively. It is indicated that the additional 2% Mn doped Ba(Zr0.2Ti0.8)O3 thin films can be used for the development of the room temperature tunable microwave elements and related device applications.

Highly directional-dependent metal-insulator transition is observed in epitaxial double perovskite LaBaCo2O5.5+δ films. The film exhibit metallic along [100], but remain semiconducting along [010] under application of a magnetic field parallel to the surface of the film. The physical origin for the properties is identified as in-plane tensile strain arising from oxygen vacancies. First-principle calculations suggested the tensile strain drastically alters the band gap, and the vanishing gap opens up [100] conduction channels for Fermi-surface electrons. Our observation of strain-induced highly directional-dependent metal-insulator transition may open up new dimension for multifunctional devices.

Highly directional-dependent metal-insulator transition is observed in epitaxial double perovskite LaBaCo2O5.5+δ films. The film exhibit metallic along [100], but remain semiconducting along [010] under application of a magnetic field parallel to the surface of the film. The physical origin for the properties is identified as in-plane tensile strain arising from oxygen vacancies. First-principle calculations suggested the tensile strain drastically alters the band gap, and the vanishing gap opens up [100] conduction channels for Fermi-surface electrons. Our observation of strain-induced highly directional-dependent metal-insulator transition may open up new dimension for multifunctional devices.

Interface engineered BaTiO3/SrTiO3 heterostructures were epitaxially grown on (001) MgO substrates by pulsed laser deposition. Microstructural characterizations by X-ray diffraction and transmission electron microscopy indicate that the as-grown heterostructures are c-axis oriented with sharp interfaces. The interface relationships between the substrate and multilayered structures were determined to be [001]SrTiO3//[001]BaTiO3//[001]MgO and (100)SrTiO3//(100)BaTiO3//(100)MgO. The high-frequency microwave (∼18 GHz) dielectric measurements reveal that the dielectric constant and dielectric loss of the nanolayered heterostructures are highly dependent upon the stacking period numbers and layer thicknesses. With the increase in the periodic number, or the decrease in each layer thickness, the dielectric constant dramatically increases and the dielectric loss tangent rapidly decreases. The strong interface effect were found when the combination period is larger than 16, or each STO layer is less than 6.0 nm. T...

Ferromagnetic thin films of the A-site nano-ordered double perovskite LaBaCo(2)O(5.5+δ) (LBCO) were grown on (001) MgO, and their structural and magnetic properties were characterized. The as-grown films have an excellent epitaxial behavior with atomically sharp interfaces, with the c-axis of the LBCO structure lying in the film plane and the interface relationship given by (100)(LBCO)//(001)(MgO) and [001](LBCO)//[100](MgO) or [010](MgO). The as-grown LBCO films exhibit a giant magnetoresistance (54% at 40 K under 7 T) and an anomalous magnetic hysteresis, depending strongly on the temperature and the applied magnetic field scan width.

Environment friendly ferroelectric relaxor Ba ( Zr 0.2 Ti 0.8) O 3 thin films with the addition of 2% Mn dopant were grown on (001) MgO substrates by pulsed laser deposition. Microstructure studies with X-ray diffraction and transmission electron microscopy reveal that the as-grown Ba ( Zr 0.2 Ti 0.8) O 3 thin films are c-axis oriented with an atomic sharp interface. The films have good single crystallinity and good epitaxial quality. The interface relationship was determined to be [100]Mn:BZT//[100]MgO and (001)Mn:BZT//(001)MgO . Nanoscale order/disorder relaxor structures were found with nano-columnar structures. The microwave dielectric measurements (15–18 GHz) indicate that the films have excellent dielectric properties with large dielectric constant value, high tunability, and low dielectric loss, promising the development of room temperature tunable microwave elements.

We report on the evolution of twin-coupled nanofinger structures in epitaxial Mn-doped Ba(Zr,Ti)O3 films on a (001) MgO substrate. XRD studies showed that the films are highly c-axis oriented epitaxial films. TEM and high-resolution TEM studies showed that Mn:BZT films present a pseudo-cubic perovskite structure composed of an epitaxial layer near the interface followed by the formation of twin-coupled nanofingers. The epitaxial grains and the twin-couple domains coexist by sharing their {111} or {110} plane as a common plane. The transition from the epilayer to nanofingers is accomplished by alternatively introducing {111} and {110} plane twin boundaries. This particular process results in gradual reduction of the lateral size of the epitaxial grains and eventually drives the epitaxial structure into twin-coupled nanofingers. The possible atomic structure models for the {110} plane twin boundary are discussed.

Microstructures of the epitaxially grown Ba(Zr,Ti)O3 (BZT) and Mn-doped Ba(Zr,Ti)O3 (Mn:BZT) thin films on (001) MgO substrate fabricated by pulsed laser deposition were studied using X-ray diffraction (XRD), transmission electron microscopy (TEM) and high-resolution TEM. The XRD studies showed that both epitaxial thin film structures are c-axis oriented. TEM and high-resolution TEM studies demonstrated that both BZT and Mn:BZT films consist of a continuous epitaxial layer near the interface followed by the formation of twin-coupled nanopillars, united by sharing their {111} or {110} plane as a common plane. The microstructure evolution from the epilayer to nanopillars is accomplished by alternatively introducing {111} and {110} plane twin boundaries, resulting in gradual shrinking/enlarging of the lateral size of the epitaxial grains/twin-coupled nanopillars. The lateral size of the nanopillars in BZT films is about four times larger than that in the Mn:BZT films. The refining of the nanopillars in the M...

We report on the fabrication of ferroelectric BaTiO3 thin films on titanium substrates using pulsed laser deposition and their microstructures and properties. Electron microscopy studies reveal that BaTiO3 films are composed of crystalline assemblage of nanopillars with average cross sections from 100 nm to 200 nm. The BaTiO3 films have good interface structures and strong adhesion with respect to Ti substrates by forming a rutile TiO2 intermediate layer with a gradient microstructure. The room temperature ferroelectric polarization measurements show that the as-deposited BTO films possess nearly the same spontaneous polarization as the bulk BTO ceramics indicating formation of ferroelectric domains in the films. Successful fabrication of such ferroelectric films on Ti has significant importance for the development of new applications such as structural health monitoring spanning from aerospace to civil infrastructure. The work can be extended to integrate other ferroelectric oxide films with various promising properties to monitor the structural health of materials.

Epitaxial (LaBa)Co2O5+δ thin films were grown on (001) LaAlO3 single-crystal substrates using pulsed laser deposition. Microstructure characterizations from X-ray diffraction and electron microscopy indicate that the films are highly c-axis oriented with cube-on-cube epitaxy. Transport property measurements indicate that the films have typical semiconductor behavior with a novel phase transition and hysteresis phenomena at 540 K. The chemical dynamic studies reveals that the resistance of the film changes drastically with the change of redox environment, i.e., the magnitude of resistance changes, ΔR = 1 × 102 ⇔ 1 × 106 Ω, is found within a short response time (∼700 ms). These phenomena suggest that the as-grown (LaBa)Co2O5+δ film have extraordinary sensitivity to reducing-oxidizing environment and the exceedingly fast surface exchange rate.

We report the twin-coupled multi-oriented domain structures in the epitaxial BZT20 (20%Zr) films grown on the (001) MgO substrate using pulsed-laser deposition. Transmission electron microscopy shows that the film consists of an epitaxial layer of pseudo-cubic perovskite structure and a nanopillar layer of multi-oriented twin domain structures near the surface. Four types of the twin domains were formed in the nanopillar layers by coherently joining their {111} with the epilayer and aligning their ⟨110⟩ directions parallel to the ⟨110⟩ axes of the epilayer. A non-uniform polarization switching behavior was observed due to the formation of such complex structure in the BZT20 films.

Ferroelectric BaTiO3 thin films were fabricated directly on various metallic substrate materials such as Ni and Ti by using the pulsed laser for the development of structural health monitoring systems and energy harvest applications. Microstructure studies from x-ray diffraction and electron microscopy indicate that the as-grown BaTiO3 thin films have pure BaTiO3 crystal phase. The TEM studies indicate that the BaTiO3 films are composed of crystalline assemblage of nanopillars with average cross sections from 100 nm to 200 nm and can be directly integrated on the Ni tapes without the formation of NiO interlayer suggesting that this system can be developed for super-capacitor devices. The BaTiO3films have good interface structures and strong adhesion with respect to Ni and Ti substrates. Dielectric measurements have shown the hysteresis loop at room temperature in the film with a large remanent polarization, indicating that the ferroelectric domains have been created in the as-deposited BTO films....

Lead Strontium Titanate ((Pb, Sr)TiO3, PST) thin films were epitaxially grown on (001) magnesium oxide (MgO), (001) lanthanum aluminate (LaAlO3, LAO), and (110) neodymium gallate (NdGaO3, NGO) substrates by pulsed laser deposition. Microstructural studies revealed that the as-grown PST films are with excellent epitaxial quality. PST films on MgO and LAO substrates exhibit a tetragonal distortion whereas the films on NGO substrates show an orthorhombic distortion. Dielectric property measurements at 1.0 MHz revealed that the room temperature dielectric constant is about 1500 with an extra large dielectric tunability value of 65% at 50 kV/cm for the PST film on the MgO substrate, and dielectric constant of 3100 with a dielectric tunability value of 48% at 50 kV/cm for the PST film on the LAO substrate. PST films on NGO substrates show anisotropic in-plane dielectric properties due to the anisotropic in-plane strain. A high zero-field dielectric constant of 4220 with a dielectric tunability value of...

Drug abuse and obesity are serious public health problems, and mounting evidence suggests that dopamine and serotonin systems are similarly involved in regulating the consumption of food and drugs. Lorcaserin, a serotonin 2C receptor agonist, was recently approved by the US FDA to help obese individuals lose weight and it might also be effective at reducing cocaine abuse. The current studies sought to (1) characterize the pharmacokinetic and behavioral profile of lorcaserin (I.G.), and (2) determine the effectiveness of lorcaserin to alter the discriminative stimulus and reinforcing effects of cocaine (I.V.) in rhesus monkeys. Administered acutely, lorcaserin dose-dependently increased the occurrence of yawning and decreased spontaneous activity and operant responding for food. These effects occurred within 30-60 min of administration and began to dissipate by 240 min, which closely matched plasma levels of lorcaserin. In monkeys discriminating cocaine from saline, lorcaserin alone did not increase cocain...

Perovskite cobaltates LaBaCo 2 O 5.5+ δ thin films were directly integrated onto (001) Si substrates by pulsed laser deposition. Microstructural studies from X-ray diffraction reveal that the LaBaCo 2 O 5.5+ δ films are polycrystalline. Electrical transport property measurements indicate that the polycrystalline LaBaCo 2 O 5.5+ δ films have a semiconductor behavior with a largest magnetoresistance value of 18% at ~40 K. Magnetization property measurements show that the polycrystalline films exhibit magnetic behavior similar to its bulk materials of nanoscale ordered LaBaCo 2 O 6 and have larger magnetic moments and magnetic coercive field than the single-crystal LaBaCo 2 O 5.5+ δ films.

Drug abuse and obesity are serious public health problems. Dopamine systems play a central role in mediating the reinforcing effects of drugs and food, and the prolonged use of drugs or consumption...

This study compared the efficacy and tolerability of two dose-titrated regimens of irbesartan, an angiotensin II receptor antagonist selective for the AT1 subtype, vs placebo in hypertensive patients when titrated to clinical response. Patients with seated diastolic blood pressure (SeDBP) 95 to 110mm Hg following a 4- to 5-week single-blind placebo lead-in period were randomised to double-blind irbesartan 75mg, 150mg or matching placebo administered orally once daily for 12 weeks. At week 6, the dose of double-blind medication was doubled for patients with SeDBP ≥90mm Hg. The primary outcome measure was change from baseline in SeDBP at week 12 of double-blind treatment. Mean changes from baseline in SeDBP were significantly greater for irbesartan 75mg/ 150mg (−8.3mm Hg) and 150mg/300mg (−10.5mm Hg) dose regimens vs placebo (−4.2mm Hg) [p < 0.01]. At week 12, greater proportions of patients receiving irbesartan 75mg/150mg and 150mg/300mg achieved normalised blood pressure (SeDBP