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The detection of off-gassed sodium from molten sodium nitrate (NaNO3) at temperatures between 330 °C and 505 °C and off-gassed calcium from molten lithium chloride–potassium chloride eutectic (LKE) mixtures at 510 °C with laser-induced breakdown spectroscopy (LIBS) was demonstrated. NaNO3 and LKE samples were melted in a custom-built crucible that promoted the generation of off-gassed products from the molten sample. The off-gassed products were analyzed with a LIBS system designed to probe the high-temperature environment. Na D emission lines, Na(I)588.99 nm and Na(I) 589.59 nm, were detected from the NaNO3 samples after reaching a temperature threshold, which indicated the occurrence of phase change. In LKE mixtures, the detection of Ca impurities at a concentration of 78 mg/kg was possible using the emission lines Ca(II) 393.66 nm and Ca(II) 395.85 nm. This work demonstrates the real-time monitoring capabilities of LIBS in high-temperature environments that simulate the conditions of molten salt reactors. Graphical Abstract This is a visual representation of the abstract. [ABSTRACT FROM AUTHOR]

Laser-induced breakdown spectroscopy (LIBS) was used to characterize the ejecta released by lithium-ion (Li-ion) cells at thermal runaway conditions. Commercial AAA-size, rechargeable, 3.7 V, 350 mAh, Li-ion battery cells were heated in a N2 -atmosphere tubular chamber up to about 165 ℃ to induce thermal decomposition. Through measurements of the chamber internal temperature and LIBS emission intensities over, time the onset temperature of thermal runaway (≈143 ℃) and the duration of the cells outgassing (>40 minutes) were determined. Relatively high-intensity atomic emissions from C, F, H, Li, Na, and P were detected at different times during the heating experiments. The detection of analytes such as C and H was continuous over time. On the contrary, detection of F, Li, Na, and P was more irregular, indicating the presence of solid-phase analytes or analyte-bearing particles. A calibration scheme for estimation of the total mass/volume concentration of all carbon-based species sampled within the laser-induced plasma was developed. [ABSTRACT FROM AUTHOR]

Background: Chlamydia pneumoniae (Cp) is an obligate intracellular human respiratory pathogen producing persisting lung infection with a plausible link to asthma pathogenesis. The population attributable risk of potentially treatable Cp infection in asthma has not been reported. Methods: The author searched from 2000 to 2020 inclusive for previously un-reviewed and new cross sectional and prospective controlled studies of Cp biomarkers and chronic asthma in both children and adults. Qualitative descriptive results and quantitative estimates of population attributable risk for selected biomarkers (specific IgG, IgA and IgE) are presented. Findings: No large, long-term prospective population-based studies of Cp infection and asthma were identified. About half of case-control studies reported one or more significant associations of Cp biomarkers and chronic asthma. Heterogeneity of results by age group (pediatric v adult asthma), severity category (severe/uncontrolled, moderate/partly controlled, mild/controlled) and antibody isotype (specific IgG, IgA, IgE) were suggested by the qualitative results and confirmed by meta-analyses. The population attributable risks for Cp-specific IgG and IgA were nul in children and were 6% (95% confidence interval 2%-10%, p = 0.002) and 13% (9%-18%, p<0.00001) respectively in adults. In contrast to the nul or small population attributable risks for Cp-specific IgG and IgA, the population attributable risk for C. pneumoniae-specific IgE (children and adults combined) was 47% (39%-55%, p<0.00001). In the subset of studies that reported on asthma severity categories, Cp biomarkers were positively and significantly (P<0.00001) associated with asthma severity. Interpretation: C. pneumoniae-specific IgE is strongly associated with asthma and asthma severity, suggesting a possible mechanism linking chronic Cp infection with asthma in a subset of individuals with asthma. Infection biomarkers should be included in future macrolide treatment trials for severe and uncontrolled asthma. [ABSTRACT FROM AUTHOR]

We have previously reported the influences of OCT1 ontogeny and genetic variation on morphine clearance in neonatal and pediatric patients. In the latter study, plasma morphine‐glucuronide levels correlated with patient genotype for the rs4793665 single‐nucleotide polymorphism (SNP) at the locus of MRP3, an efflux transporter of morphine glucuronides between hepatocytes and circulating blood. The link between MRP3 activity and overall morphine clearance has not been thoroughly investigated however, and the developmental profile of hepatic MRP3 protein expression remains thinly defined between neonates and adults. In the current study, previously determined morphine clearance values for neonatal (24‐58 weeks postmenstrual age, N = 57) and pediatric (5‐16 years, n = 85) patients were reanalyzed for correlation to the SNP genotype of patient rs4793665. Among OCT1 wild‐type patients, pediatric morphine clearance showed a significant decreasing trend by MRP3 genotypes in the order of CC > CT > TT (P =.014), whereas for neonates, an identical but nonsignificant trend was observed. Pharmacogenetic differences in MRP3 and OCT1 ontogeny were evaluated by Western blot of hepatic membrane fractions from 50 subjects aged 1 day postnatal to 33 years old. Hepatic MRP3 protein level did not vary by rs4793665 genotype, and followed an atypical developmental pattern of increase up to 1‐2 years of age, thereafter decreasing during preadolescence before increasing again to adult levels at maturity (17‐33 years). By comparison, OCT1 expression was significantly decreased in OCT1 *1/*3 genotyped patients older than 1 year and followed a trajectory consistent with prior studies. Our results suggest that consideration of MRP3 pharmacogenetics and ontogeny may aid in identifying pediatric patients having different/atypical morphine requirements. [ABSTRACT FROM AUTHOR]

This class of drugs has the potential to benefit patients with persistent, poorly controlled asthma and those with new-onset disease as an adjunct to first-line therapy. [ABSTRACT FROM AUTHOR]

The article focuses on balancing impartiality and accountability in the U.S. Internal Revenue Service (IRS) Office of Appeals. It mentions about statutory and regulatory scheme underlying collection due process (CDP) hearings; history and purposes of the Appointments Clause; and role of Congress in providing for the appointment of CDP officers by the Secretary of the Treasury to promote prospective accountability for the quality of CDP decisions.

A theory of the electromagnetic scattering from spherical shells composed of radially oriented optically anisotropic scattering elements is presented. The theory is valid for arbitrary shell size and index of refraction but is limited to moderate shell thickness compared to the shell radius. The theory includes the effect of the shell thickness to second order, thereby extending previous work by Lange and Aragón [J. Chem. Phys. 92, 4643, (1990)]. Exact closed form solutions could be obtained for some, but not all of the terms in the expansion. Extensive comparisons with exact numerical computations based on infinite series of non-integral order Bessel functions are included, as well as comparisons with the exact closed form expressions of the first order theory. The relationship of the second order theory to the Rayleigh–Debye approximation is examined and it is shown that, in contrast to the first order case, there are Mie corrections to the effects of the optical anisotropy on the scattering amplitudes. These results are useful in the interpretation of light scattering experiments from phospholipid vesicle dispersions. [ABSTRACT FROM AUTHOR]

The performance of laser-induced breakdown spectroscopy (LIBS) to identify and quantify gold and silver in ore samples was evaluated. Ores from a gold-producing mine and samples artificially doped with Au and Ag solutions to previously defined concentrations (surrogates) were prepared as 50-mm pellets prior to LIBS analysis. Silver detection and intensity measurement was straightforward for concentrations from 0.4 to 43 μg/g and from 1.1 to 375 μg/g in ore and surrogate samples, respectively. Au emission lines were not found after ensemble average or accumulation of 100-single shot LIBS spectra of ore samples containing up to 9.5 μg/g Au. However, the Au signal was present in the spectra of surrogate samples, for which a detection limit of about 0.8 μg/g was determined. When the number of sampling shots in ore samples increased, various single shot spectra registered Au emission lines. The number of spectra containing Au emission lines increased with the number of single shots. Those results, as well as scanning electron microscopy analysis of ore samples, suggest that the discrete analyte distribution as well as the inherent discrete characteristics associated to LIBS made the presence of gold in the LIBS spark an unlikely occurrence. The particle sampling rates (the percentage of laser pulses expected to sample at least one particle) were estimated for gold concentrations of 1.1 and 10.0 μg/g as 0.04% and 0.32%, respectively. A Monte Carlo simulation indicated that > 100 gold-containing particles should be sampled to accurately represent the discrete character of gold in the ore. Sampling 100 such particles requires > 10 5 laser pulses over a single pellet. Despite the fact that this rather large number of shots makes difficult to conduct conditional analysis on pellets, for some samples that withstood 5000 shots, gold quantification in ores was successfully achieved at concentrations as low as 1 μg/g. Results are encouraging and illustrate the applicability of LIBS to gold and silver in field semi-quantitative analysis. [ABSTRACT FROM AUTHOR]

Background: Patient engagement throughout research is a way to generate more relevant patient-important research questions, methods and results with the ultimate aim of facilitating translation of research into practice. Tokenism is defined as the practice of making perfunctory or symbolic efforts to engage communities or patients.Objective: We wanted to explore how tokenism might influence engaging patients in research to help researchers work towards more genuine engagement.Methods: The Community Clinician Advisory Group and Patient and Clinician Engagement program held a workshop at the 2015 North American Primary Care Research Group meeting titled 'How Do We Move beyond Tokenism in Patient Engagement?' Patients, clinicians and academic researchers contributed examples of genuine and token engagement characteristics based on personal experience and knowledge. Data were iteratively collated and categorized into domains and items.Results: Examples of genuine and token engagement were categorized into three domains: Methods/Structure of engagement, Intent and Relationship building. Members with experience in patient-engaged research projects felt that longitudinal engagement was a key element to effectively translating research into local community and practice.Conclusions: The group (i) highly valued genuine intent and relationship building as elements to combat tokenism; (ii) noted that early genuine attempts at engagement may superficially resemble tokenism as researchers build enduring and trusting relationships with patient/community partners and (iii) emphasized the importance of seeking and utilizing patient experiences throughout research. These observations may contribute to more formal methods to help researchers (and reviewers) evaluate where engagement processes sit along the 'genuine-token' continuum. [ABSTRACT FROM AUTHOR]

Asthma is a chronic respiratory disease characterized by reversible airway obstruction and airway hyperresponsiveness to non-specific bronchoconstriction agonists as the primary underlying pathophysiology. The worldwide incidence of asthma has increased dramatically in the last 40 years. According to World Health Organization (WHO) estimates, over 300 million children and adults worldwide currently suffer from this incurable disease and 255,000 die from the disease each year. It is now well accepted that asthma is a heterogeneous syndrome and many clinical subtypes have been described. Viral infections such as respiratory syncytial virus (RSV) and human rhinovirus (hRV) have been implicated in asthma exacerbation in children because of their ability to cause severe airway inflammation and wheezing. Infections with atypical bacteria also appear to play a role in the induction and exacerbation of asthma in both children and adults. Recent studies confirm the existence of an infectious asthma etiology mediated by Chlamydia pneumoniae (CP) and possibly by other viral, bacterial and fungal microbes. It is also likely that early-life infections with microbes such as CP could lead to alterations in the lung microbiome that significantly affect asthma risk and treatment outcomes. These infectious microbes may exacerbate the symptoms of established chronic asthma and may even contribute to the initial development of the clinical onset of the disease. It is now becoming more widely accepted that patterns of airway inflammation differ based on the trigger responsible for asthma initiation and exacerbation. Therefore, a better understanding of asthma subtypes is now being explored more aggressively, not only to decipher pathophysiologic mechanisms but also to select treatment and guide prognoses. This review will explore infection-mediated asthma with special emphasis on the protean manifestations of CP lung infection, clinical characteristics of infection-mediated asthma, mechanisms involved and antibiotic treatment outcomes. [ABSTRACT FROM AUTHOR]

Metallic fuel additives have been considered for soot emission control over the last few decades. However, the exact mechanisms of soot reduction are poorly understood and still remain controversial. In response to the need for identifying the state of the iron additive in the diffusion flame, laser-induced fluorescence and absorption spectroscopy were performed in a laboratory-scale isooctane diffusion laminar flame seeded with 4000 ppm iron pentacarbonyl as the metallic additive. The results of the spectroscopic techniques reveal that the dominant iron species throughout the primary flame region was Fe atoms, rather than any form of iron oxide. Moreover, elemental iron was observed to diminish through the soot oxidation region. The primary conclusion is that the catalytic effect of Fe atoms and possibly iron oxides enhanced soot oxidation in the burnout regime of the flame, thereby reducing the overall soot emissions. [ABSTRACT FROM AUTHOR]

Quantitative detection of common endogenous fluorophores is accomplished using differential laser-induced perturbation spectroscopy ( DLIPS) with a 193-nm UV fluorescence probe and various UV perturbation wavelengths. In this study, DLIPS is explored as an alternative to traditional fluorescence spectroscopy alone, with a goal of exploring natural fluorophores pursuant to biological samples and tissue analysis. To this end, aromatic amino acids, namely, l-phenylalanine, l-tyrosine and l-tryptophan are mixed with differing mass ratios and then classified with various DLIPS schemes. Classification with a traditional fluorescence probe is used as a benchmark. The results show a 20% improvement in classification performance of the DLIPS method over the traditional fluorescence method using partial least squares ( PLS) analysis. Additional multivariate analyses are explored, and the relevant photochemistry is elucidated in the context of perturbation wavelengths. We conclude that DLIPS is a promising biosensing approach with potential for in vivo analysis given the current findings with fluorophores relevant to biological tissues. [ABSTRACT FROM AUTHOR]

Over the past decade, there has been a gradual evolution of the retrievable inferior vena cava (IVC) filter, as the indications for caval filtration have expanded since the first such filters came into use. However, the particular design of retrievable or optional filters has introduced a subset of both symptomatic and asymptomatic device failures that have prompted a reassessment in the approach to patient selection as well as a new lexicon of technical considerations when considering retrieval. The Denali Vena Cava Filter (Bard Peripheral Vascular, Inc., Tempe, AZ) represents one of the latest filters to come to market that specifically addresses the various issues of its predecessors. While the body of published experience with this filter is still relatively sparse, the incidence of filter tilt, strut perforation, strut fracture, and filter migration appears acceptably low and the filters remain relatively easy to retrieve even after long dwell times. [ABSTRACT FROM AUTHOR]

Adenylyl cyclase (AC) catalyzes the synthesis of cyclic AMP, an important intracellular regulatory molecule, from ATP. We propose a catalytic mechanism for class III mammalian AC based on density functional theory calculations. We employ a model of the AC active site derived from a crystal structure of mammalian AC activated by Gα·GTP and forskolin at separate allosteric sites. We compared the calculated activation free energies for 13 possible reaction sequences involving proton transfer, nucleophilic attack, and elimination of pyrophosphate. The proposed most probable mechanism is initiated by deprotonation of 3′OH and water-mediated transfer of the 3′H to the γ-phosphate. Proton transfer is followed by changes in coordination of the two magnesium ion cofactors and changes in the conformation of ATP to enhance the role of 3′O as a nucleophile and to bring 3′O close to Pα. The subsequent phosphoryl transfer step is concerted and rate-limiting. Comparison of the enzyme-catalyzed and nonenzymatic reactions reveals that the active site residues lower the free energy barrier for both phosphoryl transfer and proton transfer and significantly shift the proton transfer equilibrium. Calculations for mutants K1065A and R1029A demonstrate that K1065 plays a significant role in shifting the proton transfer equilibrium, whereas R1029 is important for making the transition state of concerted phosphoryl transfer tight rather than loose. [ABSTRACT FROM AUTHOR]

The article explores the aspects of quality measures with pay-for-performance (P4P) approach to accountability of medical care and practitioners. Particular focus is given into the impacts of P4P incentives to medical practitioners to maximize its patient care service and its paid equitability. It also notes on the aspects of patient satisfaction for medical practice.

A combined laser-induced breakdown spectroscopy (LIBS) and Raman spectroscopy system for depth profile analyses is presented. The system incorporates a single 532 nm laser source, which is delivered through an optical fiber to the sample site. The homogenized laser beam results in well-defined cylindrical craters with diameters of 100 μm. LIBS depth profiling analyses of metals was performed applying pulse energies of about 1 mJ. The application of up to 500 pulses allowed to drill through layers of several tens of microns, while observing sharp transitions at the layer interfaces. The capability of the system for Raman spectroscopy was investigated for various polymer samples by reducing the pulse energies below the respective ablation threshold. A combined Raman/LIBS depth profiling was applied to a polymer-coated metal. Additionally, the capability of the system for calibration-free LIBS quantification (CF-LIBS) was evaluated. Quantification of major elements in metallic reference materials showed good agreement with the certified values with relative deviations of less than 30%. Finally, the optimized system was applied for depth profiling and elemental composition analysis of ancient Roman bronze rings. Overall, the presented setup combines the high flexibility of a fiber-coupled system with Raman and micro-LIBS, making the system interesting for depth profiling and elemental quantification in archaeometric as well as industrial applications. [ABSTRACT FROM AUTHOR]

Laser ablation coupled to laser-induced breakdown spectroscopy (LA-LIBS) is an analytical method, which minimizes sample matrix effects typically found in quantitative LIBS-based direct solid analyses. This paper reports the application of double-pulse laser ablation (DP-LA) to improve the analyte response and the achievable precisions of LA-LIBS. Two coaxial laser beams were applied at the ablation site and the analytical signals were then collected from a second free-standing LIBS plasma downstream of the ablation site. Signal improvements of up to one order of magnitude were observed compared to single-pulse LA-LIBS. The effect of the interpulse delay on the observed signal-to-noise ratios was studied and the quantification capabilities of the optimized DP-LA-LIBS setup were investigated for manganese and iron in a broad range of different alloy types. A linear response was observed for manganese across the different matrices, allowing for nonmatrix-matched calibrations. Matrix effects were observed when analyzing aluminum samples, which, however, could be compensated for by applying iron as internal standard. Size distributions of the ablated material and electron density measurements provide additional insight into the double-pulse process, with additional future work suggested. [ABSTRACT FROM AUTHOR]

Time-dependent density functionaltheory (TD-DFT) and electronpropagator theory (EPT) are used to calculate the electronic transitionenergies and ionization energies, respectively, of species containingphosphorus or sulfur. The accuracy of TD-DFT and EPT, in conjunctionwith various basis sets, is assessed with data from gas-phase spectroscopy.TD-DFT is tested using 11 prominent exchange-correlation functionalson a set of 37 vertical and 19 adiabatic transitions. For verticaltransitions, TD-CAM-B3LYP calculations performed with the MG3S basisset are lowest in overall error, having a mean absolute deviationfrom experiment of 0.22 eV, or 0.23 eV over valence transitions and0.21 eV over Rydberg transitions. Using a larger basis set, aug-pc3,improves accuracy over the valence transitions via hybrid functionals,but improved accuracy over the Rydberg transitions is only obtainedvia the BMK functional. For adiabatic transitions, all hybrid functionalspaired with the MG3S basis set perform well, and B98 is best, witha mean absolute deviation from experiment of 0.09 eV. The testingof EPT used the Outer Valence Green’s Function (OVGF) approximationand the Partial Third Order (P3) approximation on 37 vertical firstionization energies. It is found that OVGF outperforms P3 when basissets of at least triple-ζ quality in the polarization functionsare used. The largest basis set used in this study, aug-pc3, obtainedthe best mean absolute error from both methods -0.08 eV for OVGF and0.18 eV for P3. The OVGF/6-31+G(2df,p) level of theory is particularlycost-effective, yielding a mean absolute error of 0.11 eV. [ABSTRACT FROM AUTHOR]

Abstract: Aim: Neuroimaging has been proposed as a predictor of neurologic outcome in comatose survivors of cardiac arrest. We reviewed the quality and level of evidence of the current neuroimaging literature for predicting neurologic outcome in cardiac arrest patients treated with or without therapeutic hypothermia (TH). Data Sources: Medline, EMBASE, and Cochrane Databases were searched using the terms “cardiac arrest,” “cardiopulmonary resuscitation,” “brain hypoxia,” “brain anoxia,” “brain hypoxia-ischaemia,” “neuroimaging,” and “prognosis.” Eligible studies were reviewed and classified by level of evidence and methodological quality as defined by the International Liaison Committee on Resuscitation (ILCOR). Results: 928 studies were identified, 84 of which met inclusion criteria: 74 were supportive of neuroimaging to predict outcome, eight unsupportive, and two equivocal. Several studies investigated more than one imaging modality: 27 investigated computed tomography (CT), 46 magnetic resonance imaging (MRI), and 18 alternate imaging modalities, including positron emission tomography and single photon emission computed tomography. No randomized controlled trials were identified. Seven cohort and case control studies were identified, only one of which was graded “good” quality, two were “fair” and four were “poor.” Conclusion: Neuroimaging is an evolving modality as a prognostic parameter in cardiac arrest survivors. However, the quality of the available literature is not robust, highlighting the need for higher quality studies before neuroimaging can be supported as a standard tool for prognostication in the patient population. [Copyright &y& Elsevier]

The generation of transfer films is a common wear and lubrication mechanism of solid lubricants, such as polymers and lamellar solids. Material can transfer from a solid lubricant to a counter surface as early as the first cycle of sliding, initiating the formation of a transfer film, which can persist for the duration of sliding. Surface plasmon resonance (SPR) was used to monitor incipient molecular wear of a solid lubricant as performed here using a gold coated (50 nm) quartz prism in situ during sliding experiments. Surface-enhanced Raman spectroscopy (SERS) is a complementary technique enabling the analysis of ultra-thin transfer films. SPR and SERS experiments confirm that polytetrafluoroethylene and graphite transfer readily, with observed changes in SPR signal after one cycle of sliding, while ultra-high-molecular-weight polyethylene shows little transfer to the gold during sliding in the in situ SPR experiment. This shows the feasibility of SPR and SERS as important diagnostic tools for tribological studies. [ABSTRACT FROM AUTHOR]

The first part of this two-part review focused on the fundamental and diagnostics aspects of laser-induced plasmas, only touching briefly upon concepts such as sensitivity and detection limits and largely omitting any discussion of the vast panorama of the practical applications of the technique. Clearly a true LIBS community has emerged, which promises to quicken the pace of LIBS developments, applications, and implementations. With this second part, a more applied flavor is taken, and its intended goal is summarizing the current state-of-the-art of analytical LIBS, providing a contemporary snapshot of LIBS applications, and highlighting new directions in laser-induced breakdown spectroscopy, such as novel approaches, instrumental developments, and advanced use of chemometric tools. More specifically, we discuss instrumental and analytical approaches (e.g., double- and multi-pulse LIBS to improve the sensitivity), calibration-free approaches, hyphenated approaches in which techniques such as Raman and fluorescence are coupled with LIBS to increase sensitivity and information power, resonantly enhanced LIBS approaches, signal processing and optimization (e.g., signal-to-noise analysis), and finally applications. An attempt is made to provide an updated view of the role played by LIBS in the various fields, with emphasis on applications considered to be unique. We finally try to assess where LIBS is going as an analytical field, where in our opinion it should go, and what should still be done for consolidating the technique as a mature method of chemical analysis. [ABSTRACT FROM AUTHOR]

Background: Several Chlamydia pneumoniae (Cp) biomarkers have been associated with asthma but Cp-specific IgE (Cp IgE) has not been investigated extensively. Our objective was to investigate Cp IgE in community adult asthma patients. Methods:(1) Prevalence of Cp IgE (measured by immunoblotting) and Cp DNA (by polymerase chain reaction) in peripheral blood, and biomarker associations with asthma severity. (2) Case-control studies of Cp IgE association with asthma using healthy blood donor (study 1) and non-asthmatic clinic patient (study 2) controls. Results: Of 66 asthma subjects (mean age 40.9 years, range 5-75, 59% male, 45% ever-smokers) 33 (50%) were Cp IgE positive and 16 (24%) were Cp DNA positive (P = 0.001 for association of Cp IgE and DNA). Cp IgE was detected in 21% of mild intermittent asthma v 79% of severe persistent asthma (test for trend over severity categories, P = 0.002). Cp IgE detection was significantly (P = 0.001) associated with asthma when compared to healthy blood donor controls but not when compared to clinic controls. Conclusions: Half of this sample of community asthma patients had detectable IgE against C. pneumoniae. Cp IgE was strongly and positively associated with asthma severity and with asthma when healthy blood donor controls were used. These results support the inclusion of Cp IgE as a biomarker in future studies of infectious contributions to asthma pathogenesis. [ABSTRACT FROM AUTHOR]

A computational study of the kinetics of isomerization and elimination reactions of organophosphorus and organosulfur reactions is presented with a view to characterizing the predictive capabilities of widely applied techniques for processes that pertain to the destruction of chemical warfare agents. A set of 22 reactions has been studied, and the results have been compared to experimentally derived data. The BMK functional and the MG3S basis set have been used to compute minimum energy paths. Corrections have been added from CBS-QB3, CASSCF, and CASMP2 calculations. Thermal rate constants at experimental temperatures have been calculated with canonical variational transition state theory and small-curvature tunneling theory. The quality of these results may depend on recrossing of the variational transition state, the amount of radical or diradical character found in the minimum energy paths, or the accuracy of barrier heights. [ABSTRACT FROM AUTHOR]

The CBS-QB3 and G4 thermochemical models have been used to generate energetic, structural, and spectroscopic data on a set of molecules with trivalent or pentavalent phosphorus atoms that can serve as simulants of chemical warfare agents. Based on structural data, the conformational stabilities of these molecules are explained in terms of the anomeric interaction within the OPOC and OPSC fragments. For those cases where experimental data are available, comparisons have been made between calculated and previously reported vibrational frequencies. All varieties of bond dissociation energies have been examined except those for C-H and P=O bonds. In trivalent phosphorus molecules, the O-C and S-C bonds have the lowest dissociation energies. In the pentavalent phosphorus set, the S-C bonds, followed by P-S bonds, have the lowest dissociation energies. In the fluorinated simulant molecules, the P-F bond is strongest, and the P-C or O-C bonds are weakest. [ABSTRACT FROM AUTHOR]

Laser-induced breakdown spectroscopy (LIBS) has become a very popular analytical method in the last decade in view of some of its unique features such as applicability to any type of sample, practically no sample preparation, remote sensing capability, and speed of analysis. The technique has a remarkably wide applicability in many fields, and the number of applications is still growing. From an analytical point of view, the quantitative aspects of LIBS may be considered its Achilles' heel, first due to the complex nature of the laser–sample interaction processes, which depend upon both the laser characteristics and the sample material properties, and second due to the plasma–particle interaction processes, which are space and time dependent. Together, these may cause undesirable matrix effects. Ways of alleviating these problems rely upon the description of the plasma excitation-ionization processes through the use of classical equilibrium relations and therefore on the assumption that the laser-induced plasma is in local thermodynamic equilibrium (LTE). Even in this case, the transient nature of the plasma and its spatial inhomogeneity need to be considered and overcome in order to justify the theoretical assumptions made. This first article focuses on the basic diagnostics aspects and presents a review of the past and recent LIBS literature pertinent to this topic. Previous research on non-laser-based plasma literature, and the resulting knowledge, is also emphasized. The aim is, on one hand, to make the readers aware of such knowledge and on the other hand to trigger the interest of the LIBS community, as well as the larger analytical plasma community, in attempting some diagnostic approaches that have not yet been fully exploited in LIBS. [ABSTRACT FROM AUTHOR]

Abstract: The temporal evolution of the Si atomic emission signal produced from individual silica microspheres in an aerosolized air stream was investigated using laser-induced breakdown spectroscopy (LIBS). Specifically, the temporal evolution of Si emission from 2.47 and 4.09-micrometer-sized particles is evaluated over discrete delay times ranging from 15 to 70 µs following plasma initiation. The analyte signal profile from the microspheres, taken as the silicon atomic emission peak-to-continuum ratio, was observed to follow the same profile of silicon-rich nanoparticles over the range of delay times. The ratio of analyte signals for the 2.47 and 4.09-micrometer particles was observed to be approximately constant with plasma decay time and less than the expected mass ratio, leading to the conclusion that further vaporization and enhanced analyte response do not continue with increasing delay times for these microsphere sizes. While recent research suggests that the temporal component of analyte response is important for quantitative LIBS analysis, the current study does confirm earlier research demonstrating an upper size limit for quantitative aerosol particle analysis in the diameter range of 2 to 2.5 µm for silica microspheres. [Copyright &y& Elsevier]

The article reports on the release of the Expert Panel Report 3: Guidelines for the Diagnosis and Management of Asthma (EPR-3) by the National Heart, Lung and Blood Institute in the U.S. The report deals the extent to which guidelines cling to the principles stated by using EPR-3 as the first example. EPR-3 applied an unconventional evidence-grading system that stressed consistency and precision at the expense of patient-oriented results.

The author presents a one-page patient information sheet which contains relevant information on the advantages and disadvantages of mammography. He states that the patient handout attempts to outline the benefits and harms of screening mammography. A brief overview on the advantageous and disadvantageous aspects of breast radiography is provided.

Abstract: A precise implementation of the boundary element method has been applied to the computation of the polarizability and the Kerr constant of eight soluble proteins. The method is demonstrated to be accurate and precise by comparison with analytical values for spheroids. Two different integral equations have been solved: (1) an exact equation with explicit dielectric constant dependence, and (2) an exact equation for a metallic body. The dielectric dependence for the metallic body case is built in with a generalization of the ellipsoid formula. Both methods agree quantitatively with each other for low relative dielectric constants. A full tensor expression for the Kerr constant yields perfect agreement with experiment for some proteins and badly under reports for the rest. The protein structure is obtained from a crystallographic database and is assumed rigid throughout the TEB measurement. Electrolyte effects are neglected. The Kerr constant is dominated by the protein dipole moment and is quite sensitive to the orientation of the dipole moment relative to the principal axes of the polarizability tensor. Several possible reasons for the large discrepancy between some computed and measured values are discussed. [Copyright &y& Elsevier]

Summary: Non-unions present a particular challenge to the fracture surgeon and are frequently underestimated by the average practitioner. Although the use of ring fixation techniques is gaining in popularity, there remains a definite role for the use of bone grafting and plate fixation within certain clinical situations. The role of decortication, or petalling, as part of the surgical approach, is emphasized. This review addresses the basic considerations in choosing to use internal fixation to manage non-unions and outlines some of the principles of these techniques. Case examples are presented. [Copyright &y& Elsevier]

Objectives: The respiratory pathogen Chlamydia pneumoniae (C. pneumoniae) produces acute and chronic lung infections and is associated with asthma. Evidence for effectiveness of antichlamydial antibiotics in asthma is limited. The primary objective of this pilot study was to investigate the feasibility of performing an asthma clinical trial in practice settings where most asthma is encountered and managed. The secondary objectives were to investigate (1) whether azithromycin treatment would affect any asthma outcomes and (2) whether C. pneumoniae serology would be related to outcomes. This report presents the secondary results. Design: Randomized, placebo-controlled, blinded (participants, physicians, study personnel, data analysts), allocation-concealed parallel group clinical trial. Setting: Community-based health-care settings located in four states and one Canadian province. Participants: Adults with stable, persistent asthma. Interventions: Azithromycin (six weekly doses) or identical matching placebo, plus usual community care. Outcome Measures: Juniper Asthma Quality of Life Questionnaire (Juniper AQLQ), symptom, and medication changes from baseline (pretreatment) to 3 mo posttreatment (follow-up); C. pneumoniae IgG and IgA antibodies at baseline and follow-up. Results: Juniper AQLQ improved by 0.25 (95% confidence interval; -0.3, 0.8) units, overall asthma symptoms improved by 0.68 (0.1, 1.3) units, and rescue inhaler use decreased by 0.59 (-0.5, 1.6) daily administrations in azithromycin-treated compared to placebo-treated participants. Baseline IgA antibodies were positively associated with worsening overall asthma symptoms at follow-up (p = 0.04), but IgG was not (p = 0.63). Overall asthma symptom improvement attributable to azithromycin was 28% in high IgA participants versus 12% in low IgA participants (p for interaction = 0.27). Conclusions: Azithromycin did not improve Juniper AQLQ but appeared to improve overall asthma symptoms. Larger community-based trials of antichlamydial antibiotics for asthma are warranted. [ABSTRACT FROM AUTHOR]

The article reflects on the importance of practice-based research in managing depression. The five linked tasks of successful management are recognition, diagnosis, treatment, systematic follow-up and outcome assessment. The PRIME-MD Patient Health Questionnaire is used as a depression screening tool for primary care. Most of the office visit can be used to discuss the diagnosis, patient preferences for treatment and pharmacotherapy indications, expectations and side effects. Patients are asked to make three follow-up appointments.

Investigates the laser-induced plasma vaporization of individual silica microspheres in an aerosolized air stream. Upper size limit for complete particle vaporization; Silica particle diameter; Relation of particle vaporization to direct-plasma-particle interactions; Temporal and spatial plasma evolution.

A significant portion of research project costs is incurred before the receipt of grant funds. This poses a problem for the initiation of primary care research, especially in community practice settings. Potential investigators need financial support for staff time, training, pilot work, and grant proposal writing if primary care researchers are to compete successfully for grant funds. To find this support, we need to understand and eventually quantify the actual costs of research with attention to those that are incurred before the receipt of grant funds. We outline 10 phases of the research process and provide a model for understanding where costs are incurred and by whom. Costs include those associated with maintaining practice interest in research, supporting practice participation, and disseminating research findings. They may be incurred by either an academic center or a research network, by the practices and physicians themselves, or by an extramural funding source. The needed investment for initiating primary care research can be itemized and, with further research, quantified. This will enhance the arguments for capital investments in the primary care research enterprise. [ABSTRACT FROM AUTHOR]

Sensory functions of organs of the head and neck allow humans to interact with the environment and establish social bonds. With aging, smell, taste, vision, and hearing decline. Evidence suggests that accelerated impairment in sensory abilities can reflect a shift from healthy to pathological aging, including the development of Alzheimer's disease (AD) and other neurological disorders. While the drivers of early sensory alteration in AD are not elucidated, insults such as trauma and infections can affect sensory function. Herein, we review the involvement of the major head and neck sensory systems in AD, with emphasis on microbes exploiting sensory pathways to enter the brain (the "gateway" hypothesis) and the potential feedback loop by which sensory function may be impacted by central nervous system infection. We emphasize detection of sensory changes as first-line surveillance in senior adults to identify and remove potential insults, like microbial infections, that could precipitate brain pathology. [ABSTRACT FROM AUTHOR]

We construct polynomial automorphisms with wandering Fatou components. The four-dimensional automorphisms H lie in a one-parameter family, depending on the parameter δ ∈ C ∖ { 0 } , and as δ → 0 the automorphisms degenerate to the two-dimensional polynomial map P constructed in [2]. Our main result states that if P has a wandering domain, then H does too for δ sufficiently small. [ABSTRACT FROM AUTHOR]

BACKGROUND. Evidence-based clinical preventive services are underutilized. We explored the major factors associated with delivery of these services in a large physician-owned community-based group practice that provided care for both fee-for-service (FFS) and health maintenance organization (HMO) patient populations. METHODS. We performed a cross-sectional audit of the computerized billing data of all adult outpatients seen at least once by any primary care provider in 1995 (N = 75,621). Delivery of preventive services was stratified by age, sex, visit frequency, insurance status (FFS or HMO), and visit type (acute care only or scheduled preventive visit). RESULTS. Insurance status and visit type were the strongest predictors of clinical preventive service delivery. Patients with FFS coverage received 6% to 13% (absolute difference) fewer of these services than HMO patients. Acute-care-only patients received 9% to 45% fewer services than patients who scheduled preventive visits. The combination of these factors was associated with profound differences. CONCLUSIONS. Having insurance to pay for preventive services is an important factor in the delivery of such care. Encouraging all patients to schedule preventive visits has been suggested as a strategy for increasing delivery, but that is not practical in this setting. Assessing the need for preventive services and offering them during acute care visits has equal potential for increasing delivery. [ABSTRACT FROM AUTHOR]

Some diseases previously believed to be noninfectious, eg, peptic ulcer disease, are now known to be caused by chronic infection. Recently, chronic Chlamydia pneumoniae infection has been suggested as a cause for adult-onset asthma. The purpose of this study was to determine whether anti-chlamydial treatment would affect the natural history of this disease. Methods. An open-label, before-after treatment trial was performed in a community-based, primary care office. Forty-six patients (mean age 47.7 years; range 17 to 78) with moderate to moderately severe, stable, chronic asthma were treated a median of 4 weeks (range 3 to 9) with oral doxycycline (100 mg twice daily), azithromycin (1000 mg once weekly), or erythromycin (1000 mg daily). Post-treatment pulmonary function and asthma symptoms were compared with baseline values. Follow-up was an average of 6 months (range 1.5 to 36) post-treatment. Results. Four patients with C pneumoniae respiratory tract infection developed chronic asthma, which disappeared after treatment in each case. Of the remaining 42 seroreactive patients who were treated a mean of 6 years after the development of chronic asthma, one half had cither complete remission or major clinical improvement (3 and 18 patients, respectively). This improvement was significantly more likely to occur in patients with early disease (P=.01) and before the development of fixed obstruction (P<.01). Conclusions. Antimicrobial therapy appeared to "cure" or significantly improve asthma in approximately one half of treated adults, and the response pattern was consistent with chlamydial pathogenesis. C pneumoniae infection in asthma may be clinically important and should be investigated further. [ABSTRACT FROM AUTHOR]

Background. In the primary care setting, patients often report that their asthma began after an acute respiratory infection such as bronchitis, pneumonia, or an influenza-like illness ("infectious asthma"). Preceding respiratory illnesses such as bronchitis and pneumonia are also epidemiologic correlates of asthma in both children and adults. These associations suggest the possibility that respiratory infection is involved in the initiation of asthma in addition to the already acknowledged role of infection in asthma exacerbations. The purpose of this study was to investigate whether a history of infectious asthma influenced clinical and pulmonary function characteristics of patients with chronic asthma. Methods. Conducted in a community-based primary care practice, this is a clinical descriptive study of 92 middle-class patients who had a mean age of 37.7 years (standard deviation 15.4 years), a clinical diagnosis of chronic asthma, and baseline pulmonary function test results available for analysis. Results. There was sufficient history available to classify asthma as infectious in 41 (45%) of 92 patients. Patients with infectious asthma reported a much shorter duration of asthma symptoms than did patients with atopic, occupational, and exercise-induced asthma (5.6 vs 13.3 years, P=.001). Nevertheless, patients with infectious asthma had significantly worse percentages of predicted FEV1 and FEF25%-75%, both before and after bronchodilator therapy. Conclusions. Infectious asthma was common in this primary care setting. Compared with patients with other asthma syndromes, those with infectious asthma had worse pulmonary function despite a shorter duration of symptomatic disease. Further studies of the cause and prognosis of this clinical entity are warranted. [ABSTRACT FROM AUTHOR]

Discusses a study on the clinical characteristics of respiratory tract illness caused by Chlamydia pneumoniae. Association of Chlamydia pneumoniae exposure with the diagnosis of asthmatic bronchitis; Absence of immunoglobulin (IgM) antibody in reinfection; Relationship of Chlamydia pneumoniae with wheezing.

Feasibility of perpendicular magnetic recording up to an area density of 2.5 Tb/in² is investigated. Magnetic grains of 4 nm diameter with 1 nm oxide layer are required to achieve such a high density. Thermal stability of the grains is achieved by increasing the overall thickness of the grain. Magnetocrystalline anisotropy is graded within a grain in such a way that nucleation and propagation of the reversed domain wall matches with the available head field. Different design specifications are investigated to achieve higher objective function, i.e., energy barrier per switching field. [ABSTRACT FROM AUTHOR]

The author reflects on the issue concerning the need of health care reform in the U.S. He considers public reporting as a way to accomplish the approach and a motivation for the health care industry to make improvements in its products and services. The author also examines the features of a system of quality indicators that will include the capacity to support the effective and patient-centered goals of reform indicated by the Institute of Medicine (IOM)

Raman spectroscopy was evaluated as a sensor for detection of ammonium nitrate (NH 4 NO 3 , AN), fuel oil (FO), AN-water solutions, and AN- and FO-soil mixtures deposited on materials such as glass, synthetic fabric, cardboard and electrical tape to simulate field conditions of explosives detection. AN is an inorganic oxidizing salt that is commonly used in fertilizers and mining explosives, however, due to its widespread accessibility, AN-based explosives are also utilized for the manufacture of improvised explosive devices (IED). Pure AN crystals were ground to powder size and deposited on several substrates for Raman analysis, whereas FO was analysed in a quartz cuvette. To simulate field conditions samples of powdered AN, AN-water solutions (0.1% to 10.0% AN w/w), AN-soil (50% to 90% AN w/w) and FO-soil (50% to 75% FO w/w) were prepared and deposited on the clutter materials. Raman spectra were acquired at integration times between 0.1 and 30 s, and 3 replicate Raman measurements were carried out for each sample. The spectral window observed ranged from 300 to 3800 cm−1. Several characteristic Raman bands were found, namely, at 710 cm−1 (NO 3 −) and 1040 cm−1 (NO 3 −) for AN; 1440–1470 cm−1 (CH) and 2800–3000 cm−1 (CH) for FO; 3000–3500 cm−1 (OH) for water; and 615 cm−1 (CCl), 1254 cm−1 (CH), 1400 cm−1 (CH 2) and 1600 cm−1 (aromatic ring) for polyvinyl chloride (PVC, electrical tape). The effect of the AN concentration and integration time on the total and net Raman intensities, relative standard deviation, signal-to-noise ratio and relative limit of detection was evaluated. The relative limit of detection of AN in water was 0.1% (1 mg/g), and absolute limit of detection was 1.0 μg. The optimum integration time (≈10 s) for the Raman sensor to capture the analyte signals was estimated based on the Raman figures of merit as a function of the integration time. Unlabelled Image • Raman figures of merit versus integration time and ammonium nitrate concentration • The absolute limit of detection of ammonium nitrate dissolved in water is 1.0 μg. • The relative limit of detection of ammonium nitrate dissolved in water is 0.1%. • Evaluation of the effect of clutter materials on the Raman performance [ABSTRACT FROM AUTHOR]