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Having sufficient medical countermeasures (MCMs) available for the treatment of acetylcholinesterase-inhibiting nerve agent poisoned patients following a mass chemical exposure is a challenge for communities. After stockpiles containing auto-injectors are exhausted, communities need to be aware of alternative pharmaceutical options. The Department of Homeland Security Chemical Defense Program convened a federal interagency working group consisting of first responders, clinicians, and experts from the fields of medical toxicology, pharmacology, and emergency management. A literature review of pharmaceutical alternatives for treating nerve agent toxicity was performed. Pharmaceuticals that met the federal Public Health Emergency Medical Countermeasures Enterprise Product Specific Requirements were prioritized. Food and Drug Administration approval for one indication, market availability, and alignment to government procurement strategy were considered. This article summarizes the literature on comparative pharmacokinetics and efficacy against nerve agents (where available) of Food and Drug Administration approved drugs with muscarinic acetylcholine receptor antagonist and gamma-aminobutyric acid receptor agonist effects. This work is intended to serve as a resource of pharmaceutical options that may be available to communities (ie, emergency managers, planners, clinicians, and poison centers) when faced with a mass human exposure to a nerve agent and inadequate supplies of MCMs. (Disaster Med Public Health Preparedness. 2019;13:605-612)
Soybean consultants from Arkansas, Louisiana, southeast Missouri, Mississippi, and Tennessee were surveyed in 2016 to assess weed management practices and the prevalence of herbicide-resistant weeds in midsouthern U.S. soybean production. The consultants surveyed represented 13%, 28%, 8%, 16%, and 5% of the total soybean area planted in Arkansas, Louisiana, southeast Missouri, Mississippi, and Tennessee, respectively. Of the total scouted area, 78% of the consultants said their growers planted glyphosate-resistant soybean in 2016, with 18% planting glufosinate-resistant (LibertyLink®), primarily due to familiarity with and cost of the technology. Although 94% of the consultants determined that glufosinate was most effective on killing Palmer amaranth, the primary concern associated with controlling herbicide-resistant weeds was the associated cost, followed by return profit and time constraints. Palmer amaranth, morningglory species, horseweed, barnyardgrass, and Italian ryegrass were the five most problematic weeds in soybean across the five states. Palmer amaranth was the most problematic and important weed in each state individually. The increased concern (77% of consultants) with this species was attributed to the rising concern with and occurrence of protoporphyrinogen oxidase–resistant Palmer amaranth. Consultants were of the opinion that more research was needed on cover crops and the new traited technologies in order to improve weed management in soybean.
Inadvertent hyperthermia during anaesthesia is a rare but life-threatening complication. We have encountered several cases of severe hyperthermia in paediatric patients undergoing anaesthesia for cochlear implantation.
This study aimed to describe the clinical characteristics of children who developed hyperthermia while undergoing cochlear implantation, and to explore possible mechanisms and predisposing factors. The anaesthetic charts of all patients aged under 18 years who underwent cochlear implantation, or mastoid or ophthalmic surgery, between 1 January 2006 and 31 December 2009, at Soroka Medical Center in Beer Sheva, Israel, were reviewed. Patients undergoing mastoid and ophthalmic surgical procedures were used as controls.
A larger percentage of patients who underwent cochlear implant surgery (10 per cent) developed hyperthermia compared to controls (0.7 per cent, p < 0.05). In five of the seven cases, hyperthermia appeared in combination with tachycardia and hypercapnia, adhering to the clinical triad of malignant hyperthermia.
Patients undergoing cochlear implantation are susceptible to developing intra-operative hyperthermia. This article describes the hyperthermic events that occur during paediatric cochlear implantation, and attempts to identify potential triggers of hyperthermia.
We present an all-sky star count model at 12 μm based upon the Infrared Astronomical Satellite (IRAS) observations that characterize both the 12 μm luminosity function and the geometrical parameters of the galaxy. The model includes five galactic components: the bulge, the spheroid, the exponential disk, the spiral arms, and the molecular ring. The distribution of the brighter IRAS sources along the galactic plane required that the model include sources within the spiral arms and the molecular ring to produce an acceptable fit. We do not support the conclusion of Habing (1988) that the galactic disk ends just outside the solar circle, and do not require a thick disk to match the observations. We suggest that Habing's sample includes IRAS sources in the spiral arms but his model for the galactic disk does not include this critical component.
We have completed a Chandra snapshot survey of 54 radio jets that are extended on arcsec scales. These are associated with flat spectrum radio quasars spanning a redshift range z=0.3 to 2.1. X-ray emission is detected from the jet of approximately 60% of the sample objects. We assume minimum energy and apply conditions consistent with the original Felten-Morrison calculations in order to estimate the Lorentz factors and the apparent Doppler factors. This allows estimates of the enthalpy fluxes, which turn out to be comparable to the radiative luminosities.
Recent research indicates that cognitive reserve mitigates the clinical expression of neuropsychological impairment in multiple sclerosis (MS). This literature primarily uses premorbid intelligence and lifetime experiences as indicators. However, changes in current recreational activities may also contribute to the maintenance of neural function despite brain atrophy. We examined the moderation effects of current changes in recreational activity on the relationship between brain atrophy and information processing speed in 57 relapsing-remitting MS patients. Current enrichment was assessed using the Recreation and Pastimes subscale from the Sickness Impact Profile. In patients reporting current declines in recreational activities, brain atrophy was negatively associated with cognition, but there was no such association in participants reporting stable participation. The MRI metric-by-recreational activity interaction was significant in separate hierarchical regression analyses conducted using third ventricle width, neocortical volume, T2 lesion volume, and thalamic volume as brain measures. Results suggest that recreational activities protect against brain atrophy's detrimental influence on cognition. (JINS, 2013, 19, 1–6)
To describe the implementation of an institution-wide, multiple-step intervention to curtail the epidemic spread of carbapenem-resistant Klebsiella pneumoniae (CRKP).
Consecutive intervention analyses.
Patients and Setting.
All patients admitted to a 775-bed tertiary care medical center in Jerusalem, Israel, from 2006 through 2010.
The effects of 4 interventions were assessed: (1) a policy of isolation for patients colonized or infected with CRKP in single rooms, which was started in March 2006; (2) cohorting of CRKP patients with dedicated nursing staff and screening of patients neighboring a patient newly identified as a carrier of CRKP, which was started in March 2007; (3) weekly active surveillance of intensive care unit patients, which was started during August 2008; and (4) selective surveillance of patients admitted to the emergency department, which was started in March 2009. Interrupted regression analysis and change-point analysis were used to assess the effect of each intervention on the CRKP epidemic.
Patient isolation alone failed to control the spread of CRKP, with incidence increasing to a peak of 30 new cases per 1,000 hospital beds per month. Institution of patient cohorting led to a steep decline in the incidence of CRKP acquisition (P< .001). Introduction of active surveillance interventions was followed by a decrease in the incidence of CRKP-positive clinical cultures but an increase in the incidence of CRKP-positive screening cultures. The mean prevalence of CRKP positivity for the period after cohorting began showed a statistically significant change from the mean prevalence in the preceding period (P< .001).
The cohorting of patients with dedicated staff, combined with implementation of focused active surveillance, effectively terminated the epidemic spread of CRKP. Cohorting reduced cross-infection within the hospital, and active surveillance allowed for earlier detection of carrier status. Both interventions should be considered in attempts to contain a hospital epidemic.
Ferroelectric Pb(Zr1划xTix)O3 (PZT) films have been extensively studied for active components in microelectromechanical systems. The properties of PZT films depend on many parameters, including composition, orientation, film thickness and microstructure. In this study, the effects of crystallographic orientation on the dielectric and transverse piezoelectric properties of Pb(Zr0.52Ti0.48)O3 (PZT 52/48) films are reported. Crack free random and highly (100) oriented PZT(52/48) films up to ∼ 7 μm thick were deposited using a sol-gel process on Pt (111)/Ti/SiO2/Si and Pt(100)/SiO2/Si substrates, respectively. The dielectric permittivity (at 1kHz) for the (100) oriented films was 980-1000, and for the random films ∼ 930-950. In both cases, tanä was less than 0.03. The remanent polarization (∼ 30 μC/cm2) of random PZT films was larger than that of (100) oriented PZT films. The transverse piezoelectric coefficient (d31(eff)) of PZT films was measured by the wafer flexure method. The d31(eff) coefficient of random PZT thick films (-80pC/N) was larger than that of (100) oriented films (-60pC/N) when poled at 80 kV/cm for 15 min.
We have investigated the structural, compositional, interfacial, surface morphological and dielectric properties of Ba0.6Sr0.4TiO3 solid solution thin films La doped from 0 to 10 mol%. The doped thin films were prepared by the metalorganic solution deposition technique using carboxylate-alkoxide precursors. After post-deposition annealing in oxygen ambient at 750 °C the films were characterized via x-ray diffraction, Auger electron microscopy, field emission scanning electron microscopy, and atomic force microscopy. The electrical measurements were achieved in the metal-insulator-metal (MIM) configuration with Pt as the top and bottom electrode. Our results demonstrated that La doping had a strong effect on the films microstructural, dielectric and insulating properties. Specifically, 1 mol% La doped BST films exhibited a lower dielectric constant, 283 and higher resistivity 31.4×1013 W-cm with respect to that of undoped BST. The loss tangent and tunability (at 100 kHz) of the 1 mol% La doped BST films were 0.019 and 21% (at E=300kV/cm) respectively.
Bi-layered ferroelectric compounds are considered most promising for non-volatile memory applications due to their high fatigue endurance. We have prepared SrBi2Ta2O9 powders with Ba (A sites) and Nb (B sites) substitutions using a novel solution based route. The powders were pressed and sintered at 1050°C to obtain high quality targets. Thin films were prepared using these ceramic targets on Pt/TiO2/SiO2/Si substrates using pulsed laser deposition (PLD) technique. The effects of growth conditions on phase formation as well as structural and electrical properties in films are studied. Initial results on films show good hysteretic characteristics. Though phase formation begins at much lower temperature, these films crystallize in a complete layered perovskite phase when prepared at 700°C. Optical phonon modes in these materials exhibit systematic variations with changing compositions. The changes in the Raman spectra are explained in terms of Ba and Nb substitutions at A and B sites, respectively. The temperature dependence of Raman spectra exhibits the substitution induced changes in the transition temperatures of these materials.
We have investigated the electrophoretic deposition (EPD) as a low cost and conformal method of fabricating barium strontium titanium (BST) based composite thick films. The films were deposited at a controlled rate on platinum substrate in acetone-based slurry under electric bias. Acetone-aerosol OTS surfactant dispersion was used as dispersive medium. Conformal BST based thick films of 10-80 μm were obtained. The dielectric constant and dielectric loss factor of Ba0.60Sr0.40TiO3 and Ba0.60Sr0.40TiO3 – 20wt% compositions were 603.3 and 0.029 and 327.0 and 0.002, respectively. The low frequency electronic properties of the electrophoretic films were also compared with those of the bulk BST ceramics. In addition, the optical and the structural properties of the films are also discussed. The various techniques employed include x-ray diffraction, SEM and surface profilometer.
Focused ion beam milling was used to fabricate ferroelectric islands in Pb-Zr-Ti-O thin films. The islands ranged in size from 200μm×200μm to 0.3μm×0.3μm. The inverse piezoelectric effect was studied in these islands as a function of their size by tracking the surface displacement of the top electrode of the island (under an applied electric field) using an atomic force microscope (AFM). It was found that there was a substantial increase in the piezoresponse as the size of the island decreased below 100μm×100μm. This increase was attributed to the elastic deformation of the substrate.
We have used the new approach to fatigue phenomenon for analysis of the switching current and C-V characteristic evolution during cycling in PZT thin films. It was shown that in accordance with theoretical predictions the rejuvenation stage precedes the fatigue one. We have demonstrated that fatigue behavior corresponds to the spreading of the internal bias field distribution function during ac switching.
Lead titanate was prepared by the sol-gel processing of metal alkoxide solutions. The effects of hydrolysis level (i.e., moles H2O/mole PbTiO3) and acid and base additions (HNO3 or NH4OH) on the properties of desiccated gels, and the gel-to-ceramic conversion, were studied. Microstructural, structural, and physical properties were characterized at three stages of the processing cycle: (i) the desiccated gel state; (ii) the amorphous state, following organic pyrolysis; and (iii) the crystalline state. Differences in the physical and structural properties for the desiccated gels, which were induced through manipulation of the hydrolysis conditions, persisted in the amorphous state after organic pyrolysis. Minor differences remained after crystallization. Variations in material properties, with low temperature processing (e.g., the gel-to-glass transformation), were considered from the standpoint of hydrolysis and additive effects on the gel network structure and consolidation behavior. Data are reported for the densification and crystallization behavior for the gels. Through proper control of hydrolysis conditions, relatively dense ceramics were obtained at temperatures as low as 700°C.
The electronic structure of the Pu-based superconductor PuCoGa5 and the Pauli paramagnet UCoGa5 is investigated using photoemission spectroscopy. The photoemission data of PuCoGa5 reveal features at the Fermi energy EF and about 1-1.5 eV below EF indicative of itinerant and localized f-electrons, respectively. Angle-resolved spectra of UCoGa5 show two peaks at similar energies that are highly dispersive, providing evidence for itinerant character of the f-electrons in this material. A comparison of the PuCoGa5 and UCoGa5 data to the spectra of α-Pu and δ-Pu serves to place PuCoGa5 within the context of the more general electronic structure problem in elemental Pu.
Time-resolved photoinduced reflectivity data were measured for the itinerant antiferromagnet UNiGa5 (TN ≈ 85 K) from room temperature down to 10 K. The relaxation time τ increases sharply near TN, which we attribute to the opening of a spin gap. In addition, at the lowest temperatures τ increases with a T1 dependence, which is similar to that shown by the heavy fermion YbAgCu4, but with no blocking of electron-phonon scattering within the DOS peak. The transient amplitude increase at TN with a temperature dependence that is consistent with the appearance of a spin gap.