Rapid, Specific Determination of Iodine and Iodide by Combined Solid-Phase Extraction/Diffuse Reflectance Spectroscopy

A new, rapid methodology for trace analysis using solid-phase extraction is described. The two-step methodology is based on the concentration of an analyte onto a membrane disk and on the determination by diffuse reflectance spectroscopy of the amount of analyte extracted on the disk surface. This method, which is adaptable to a wide range of analytes, has been used for monitoring ppm levels of iodine and iodide in spacecraft water. Iodine is used as a biocide in spacecraft water. For these determinations, a water sample is passed through a membrane disk by means of a 10-mL syringe that is attached to a disk holder assembly. The disk, which is a polystyrene−divinylbenzene composite, is impregnated with poly(vinylpyrrolidone) (PVP), which exhaustively concentrates iodine as a yellow iodine−PVP complex. The amount of concentrated iodine is then determined in only 2 s by using a hand-held diffuse reflectance spectrometer by comparing the result with a calibration curve based on the Kubelka−Munk function. The same general procedure can be used to determine iodide levels after its facile and exhaustive oxidation to iodine by peroxymonosulfate (i.e., Oxone reagent). For samples containing both analytes, a two-step procedure can be used in which the iodide concentration is calculated from the difference in iodine levels before and after treatment of the sample with peroxymonosulfate. With this methodology, iodine and iodide levels in the 0.1−5.0 ppm range can be determined with a total workup time of ∼60 s with a RSD of ∼6%

Rapid, Low Level Determination of Silver(I) in Drinking Water by Colorimetric–solid-phase Extraction

A rapid, highly sensitive two-step procedure for the trace analysis of silver(I) is described. The method is based on: (1) the solid-phase extraction (SPE) of silver(I) from a water sample onto a disk impregnated with a silver-selective colorimetric reagent, and (2) the determination of the amount of complexed analyte extracted by the disk by diffuse reflectance spectroscopy (DRS). This method, called colorimetric–solid-phase extraction (C–SPE), was recently shown effective in determining low concentrations (0.1–5.0 mg/ml) of iodine and iodide in drinking water. This report extends C–SPE to the trace (∼4 μg/l) level monitoring of silver(I) which is a biocide used on the International Space Station (ISS). The determination relies on the manually driven passage of a water sample through a polystyrene–divinylbenzene disk that has been impregnated with the colorimetric reagent 5-(p-dimethylaminobenzylidene) rhodanine (DMABR) and with an additive such as a semi-volatile alcohol (1,2-decanediol) or nonionic surfactant (Brij 30). The amount of concentrated silver(I) is then determined in a few seconds by using a hand-held diffuse reflectance spectrometer, with a total sample workup and readout time of ∼60 s. Importantly, the additive induces the uptake of water by the disk, which creates a local environment conducive to silver(I) complexation at an extremely high concentration factor (∼800). There is no detectable reaction between silver(I) and impregnated DMABR in the absence of the additive. This strategy represents an intriguing new dimension for C–SPE in which additives, directly loaded in the disk material, provide a means to manipulate the reactivity of the impregnated reagent

Relationship between Arterial Stiffness and Heart Rate Recovery in Apparently Healthy Adults

Ding-Yu Fei1, Ross Arena2, James A Arrowood3, Kenneth A Kraft41Department of Biomedical Engineering, 2Department of Physical Therapy, 3Department of Internal Medicine, Division of Cardiology, 4Department of Radiology, Virginia Commonwealth University, Richmond, VA, USAIntroduction: Arterial stiffness and heart rate recovery (HRR) following exercise testing have emerged as variables holding significant prognostic value in a number of populations. The purpose of the present study is to examine the relationship between arterial stiffness and HRR in a group of apparently healthy subjects.Methods: Two hundred and nine apparently healthy subjects underwent maximal exercise testing. Heart rate at one and two minutes post exercise was subtracted from maximal heart rate during the exercise test to produce two measures of heart rate recovery. Aortic wave velocity, in meters per second, was obtained via a new magnetic resonance technique. Results: Pearson Product Moment Correlation analysis revealed a significant correlation between aortic wave velocity and heart rate recovery. Stepwise linear regression analysis revealed that age, maximal aerobic capacity, heart rate recovery at one minute, and diastolic blood pressure were all significant predictors of aortic wave velocity (r = 0.63, r2 = 0.40, p < 0.001). Conclusions: The results of the present study indicate that heart rate recovery is significantly correlated with a measure of large artery stiffness and adds predictive value to other clinical variables. This analysis provides further evidence that assessment of heart rate recovery should be considered in subjects undergoing exercise testing in clinical practice.Keywords: exercise testing, oxygen consumption, aortic wave velocit

Impact of a Blood Pressure Practice Initiative on Attitude, Practice Behavior, and Knowledge among Outpatient Rehabilitation Providers: An Observational Study

Purpose:The purpose of this study is to describe the impact of a blood pressure (BP) educational initiative on the attitude, practice behaviors, and knowledge of outpatient (OP) physical therapists. Methods:An observational pre-test and post-test study design was initiated using a sample of convenience at 12 OP rehabilitation clinics. A 4-phase protocol included (1) evaluation of BP equipment, (2) pre-test questionnaire, (3) attendance at a 1-hour lecture on BP practice recommendations, and (4) performing BP measures on patient evaluations for 1 week followed by the post-test questionnaire. Descriptive statistics reported demographics, whereas a paired t test compared means of the presurvey and postsurvey responses with statistical significance set at P \u3c.05. Results:Of the 55 therapists included, 70.9% were female and 29.1% male, whereas 41.8% and 58.2% reported having ≤15 and \u3e15 years of experience, respectively. A significant improvement in BP attitudes (P =.02), practice behaviors (P =.001), and knowledge (P =.002) was identified. Conclusions:An educational initiative that provided BP assessment tools, a 1-hour evidence-based BP lecture, a decision-making reference, and a directive to perform valid and reliable BP techniques and interventions resulted in positive changes to an OP therapists attitude, immediate practice behavior, and knowledge of BP

Comparison of Non-Exercise Cardiorespiratory Fitness Prediction Equations in Apparently Healthy Adults

Aims: A recent scientific statement suggests clinicians should routinely assess cardiorespiratory fitness using at least non-exercise prediction equations. However, no study has comprehensively compared the many non-exercise cardiorespiratory fitness prediction equations to directly-measured cardiorespiratory fitness using data from a single cohort. Our purpose was to compare the accuracy of non-exercise prediction equations to directly-measured cardiorespiratory fitness and evaluate their ability to classify an individual\u27s cardiorespiratory fitness. Methods: The sample included 2529 tests from apparently healthy adults (42% female, aged 45.4 ± 13.1 years (mean±standard deviation). Estimated cardiorespiratory fitness from 28 distinct non-exercise prediction equations was compared with directly-measured cardiorespiratory fitness, determined from a cardiopulmonary exercise test. Analysis included the Benjamini-Hochberg procedure to compare estimated cardiorespiratory fitness with directly-measured cardiorespiratory fitness, Pearson product moment correlations, standard error of estimate values, and the percentage of participants correctly placed into three fitness categories. Results: All of the estimated cardiorespiratory fitness values from the equations were correlated to directly measured cardiorespiratory fitness (p \u3c 0.001) although the R2 values ranged from 0.25-0.70 and the estimated cardiorespiratory fitness values from 27 out of 28 equations were statistically different compared with directly-measured cardiorespiratory fitness. The range of standard error of estimate values was 4.1-6.2 ml·kg-1·min-1. On average, only 52% of participants were correctly classified into the three fitness categories when using estimated cardiorespiratory fitness. Conclusion: Differences exist between non-exercise prediction equations, which influences the accuracy of estimated cardiorespiratory fitness. The present analysis can assist researchers and clinicians with choosing a non-exercise prediction equation appropriate for epidemiological or population research. However, the error and misclassification associated with estimated cardiorespiratory fitness suggests future research is needed on the clinical utility of estimated cardiorespiratory fitness. Keywords: Prognosis; cardiopulmonary exercise test; exercise test; fitness algorithm; maximum oxygen consumption

Accuracy of Nonexercise Prediction Equations for Assessing Longitudinal Changes to Cardiorespiratory Fitness in Apparently Healthy Adults: BALL ST Cohort

Background Repeated assessment of cardiorespiratory fitness (CRF) improves mortality risk predictions in apparently healthy adults. Accordingly, the American Heart Association suggests routine clinical assessment of CRF using, at a minimum, nonexercise prediction equations. However, the accuracy of nonexercise prediction equations over time is unknown. Therefore, we compared the ability of nonexercise prediction equations to detect changes in directly measured CRF. Methods and Results The sample included 987 apparently healthy adults from the BALL ST (Ball State Adult Fitness Longitudinal Lifestyle Study) cohort (33% women; average age, 43.1±10.4 years) who completed 2 cardiopulmonary exercise tests ≥3 months apart (3.2±5.4 years of follow-up). The change in estimated CRF (eCRF) from 27 distinct nonexercise prediction equations was compared with the change in directly measured CRF. Analysis included Pearson product moment correlations, SEE values, intraclass correlation coefficient values, Cohen\u27s κ coefficients, γ coefficients, and the Benjamini-Hochberg procedure to compare eCRF with directly measured CRF. The change in eCRF from 26 of 27 equations was significantly associated to the change in directly measured CRF (P\u3c0.001), with intraclass correlation coefficient values ranging from 0.06 to 0.63. For 16 of the 27 equations, the change in eCRF was significantly different from the change in directly measured CRF. The median percentage of participants correctly classified as having increased, decreased, or no change in CRF was 56% (range, 39%-61%). Conclusions Variability was observed in the accuracy between nonexercise prediction equations and the ability of equations to detect changes in CRF. Considering the appreciable error that prediction equations had with detecting even directional changes in CRF, these results suggest eCRF may have limited clinical utility

Cynara cardunculus L. gasification in a bubbling fluidized bed: the effect of magnesite and olivine on product gas, tar and gasification performance

peer-reviewedGasification of Cynara cardunculus L. was performed in a bubbling fluidized bed (BFB) using air as gasifying agent and, magnesite and olivine as different bed materials. Temperature was varied during the experiments (700-800 degrees C) with fixed biomass feeding and air flow rate. The effect of using the magnesite and olivine on gas and tar composition, carbon and biomass conversion, and cold gas efficiency was investigated. The product gas showed high hydrogen content (13-16% v/v) for both magnesite and olivine in the studied temperature range. Higher heating value and gas yield were improved with increasing the temperature from 700 to 800 degrees C. Biomass and carbon conversion were greater than 75%, obtaining values higher than 90% for both 700 and 800 degrees C in magnesite and for 800 degrees C in olivine. Small differences in total tar were observed between materials, although tar composition was very different. BTEX were higher for olivine and similar PAHs was obtained for both magnesite and olivine. A higher catalytic activity at 800 degrees C was observed for magnesite. Gasification performance was better with magnesite at 700 degrees C while olivine showed better properties at 800 degrees C. (C) 2016 Elsevier Ltd. All rights reserved.ACCEPTEDpeer-reviewe

Automated Referral to Cardiac Rehabilitation following Coronary Artery Bypass Grafting is associated with limited improvements in program completion: a large cohort study

Introduction Cardiac Rehabilitation (CR) reduces residual cardiovascular risk among patients who have received coronary artery bypass grafting (CABG) surgery. However, many patients do not attend and some are never referred. It is unclear whether automated referral is associated with improved CR completion rates. Objectives and Approach Geographically inclusive databases were linked to assess the impact of automated referral on rates of referral to and completion of CR post-CABG. Automated referral to CR post-CABG was instituted in Calgary on July 1, 2007. All subjects receiving CABG in Calgary between January 1, 1996 and March 31, 2016 were enrolled in the study. The Alberta Provincial Project for Outcome Assessment in Coronary Heart disease (APPROACH) database, TotalCardiology-Rehabilitation (TC-R) database, and provincial vital statistics were linked using the unique Provincial Health Number available for each patient. The association between CR referral, completion, and survival was assessed using proportional hazard models. Results There were 28,100 patients referred to the CR program, of which 26,411 were linked to the APPROACH database for a 93.99\% linkage rate. After excluding patients who did not receive CABG, a total of 8,118 patients were identified as the study population [mean age 66.2 (SD 10.2) years, 18.9\% female] during the study period: 5,103 prior to implementation of automated referral, and 3,015 post-automation. Rates of referral increased from 39.5\% prior to automation to 75.0\% post-automation (p Conclusion/Implications Automated referral to CR is associated with increased referral rates but less dramatic increases in CR completion rates post-CABG. Given the significant improvement in survival associated with CR completion, further work is needed to improve CR referral, and more importantly, CR completion rates

Search for Rare and Forbidden 3-body Di-muon Decays of the Charmed Mesons D+ and Ds+

Using a high statistics sample of photo-produced charm particles from the FOCUS experiment at Fermilab, we report results of a search for eight rare and Standard-Model-forbidden decays: D+, Ds+ > h+/- muon-/+ muon+ (with h=pion or Kaon). Improvement over previous results by a factor of 1.7--14 is realized. Our branching ratio upper limit D+ > pion+ muon- muon+ of 8.8E-6 at the 90% C.L. is below the current MSSM R-Parity violating constraint.Comment: 17 pages, 7 figure file