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1.
Indoor Air ; 26(5): 687-701, 2016 10.
Article in English | MEDLINE | ID: mdl-26340686

ABSTRACT

Traffic emissions have been associated with a wide range of adverse health effects. Many schools are situated close to major roads, and as children spend much of their day in school, methods to reduce traffic-related air pollutant concentrations in the school environment are warranted. One promising method to reduce pollutant concentrations in schools is to alter the timing of the ventilation so that high ventilation time periods do not correspond to rush hour traffic. Health Canada, in collaboration with the Ottawa-Carleton District School Board, tested the effect of this action by collecting traffic-related air pollution data from four schools in Ottawa, Canada, during October and November 2013. A baseline and intervention period was assessed in each school. There were statistically significant (P < 0.05) reductions in concentrations of most of the pollutants measured at the two late-start (9 AM start) schools, after adjusting for outdoor concentrations and the absolute indoor-outdoor temperature difference. The intervention at the early-start (8 AM start) schools did not have significant reductions in pollutant concentrations. Based on these findings, changing the timing of the ventilation may be a cost-effective mechanism of reducing traffic-related pollutants in late-start schools located near major roads.


Subject(s)
Air Pollutants/analysis , Air Pollution, Indoor/analysis , Schools , Time Factors , Vehicle Emissions/analysis , Ventilation/methods , Environmental Monitoring/methods , Humans , Ontario
2.
Faraday Discuss ; 183: 47-65, 2015.
Article in English | MEDLINE | ID: mdl-26369362

ABSTRACT

Carbon Dioxide Utilisation (CDU) processes face significant challenges, especially in the energetic cost of carbon capture from flue gas and the uphill energy gradient for CO2 reduction. Both of these stumbling blocks can be addressed by using alkaline earth metal compounds, such as Grignard reagents, as sacrificial capture agents. We have investigated the performance of these reagents in their ability to both capture and activate CO2 directly from dried flue gas (essentially avoiding the costly capture process entirely) at room temperature and ambient pressures with high yield and selectivity. Naturally, to make the process sustainable, these reagents must then be recycled and regenerated. This would potentially be carried out using existing industrial processes and renewable electricity. This offers the possibility of creating a closed loop system whereby alcohols and certain hydrocarbons may be carboxylated with CO2 and renewable electricity to create higher-value products containing captured carbon. A preliminary Techno-Economic Analysis (TEA) of an example looped process has been carried out to identify the electrical and raw material supply demands and hence determine production costs. These have compared broadly favourably with existing market values.

3.
Diabet Med ; 30(10): 1160-71, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23663156

ABSTRACT

AIMS: Sulphonylurea use has been linked with increased cardiovascular disease risk; however, previous studies have been inconsistent. Type 2 diabetes independently increases risk for cardiovascular disease, so understanding the link between longer-term use of anti-diabetic medications and cardiovascular disease has important clinical implications. METHODS: Literature search in MEDLINE and CENTRAL was conducted throughout December 2011 for clinical and observational studies that reported the association between sulphonylurea and cardiovascular disease events. Ratios (relative risk, odds ratios or hazard ratios) adjusted for potential confounders (concomitant medications, baseline cardiovascular risk, diabetes severity) were pooled using a random-effects model to yield relative risks and associated 95% confidence intervals. RESULTS: This meta-analysis included 33 studies (n = 1,325,446 patients), followed for a range of 0.46-10.4 years. In all studies, compared with other oral diabetes drugs, sulphonylurea use was associated with a significantly increased risk of cardiovascular death (relative risk 1.27, 95% confidence interval 1.18-1.34, n = 27 comparisons) and composite cardiovascular event (including myocardial infarction, stroke, cardiovascular-related hospitalization or cardiovascular death) (relative risk 1.10, 95% confidence interval 1.04-1.16, n = 43 comparisons). In studies comparing sulphonylurea vs. metformin, these relative risks were 1.26 (95% confidence interval 1.17-1.35, n = 17 comparisons) and 1.18 (95%confidence interval 1.13-1.24, n = 16 comparisons), respectively. CONCLUSIONS: Results suggest that sulphonylurea use may elevate the risk of cardiovascular disease among patients with diabetes. This meta-analysis expands the pool of studies evaluating cardiovascular mortality compared with prior observations while using adjusted estimates, and assessing an additional outcome of a composite cardiovascular event. This finding warrants consideration in clinical practice when other treatment options may be available.


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Diabetic Angiopathies/chemically induced , Hospitalization/statistics & numerical data , Myocardial Infarction/chemically induced , Stroke/chemically induced , Sulfonylurea Compounds/adverse effects , Diabetes Mellitus, Type 2/mortality , Diabetic Angiopathies/mortality , Diabetic Angiopathies/prevention & control , Female , Humans , Incidence , Male , Myocardial Infarction/mortality , Myocardial Infarction/prevention & control , Risk Factors , Stroke/mortality , Stroke/prevention & control
4.
Biomicrofluidics ; 4(1): 14107, 2010 Mar 08.
Article in English | MEDLINE | ID: mdl-20644676

ABSTRACT

A microfluidic glass chip system incorporating a quartz crystal microbalance (QCM) to measure the square root of the viscosity-density product of room temperature ionic liquids (RTILs) is presented. The QCM covers a central recess on a glass chip, with a seal formed by tightly clamping from above outside the sensing region. The change in resonant frequency of the QCM allows for the determination of the square root viscosity-density product of RTILs to a limit of approximately 10 kg m(-2) s(-0.5). This method has reduced the sample size needed for characterization from 1.5 ml to only 30 mul and allows the measurement to be made in an enclosed system.

5.
Anal Chem ; 81(4): 1628-37, 2009 Feb 15.
Article in English | MEDLINE | ID: mdl-19161303

ABSTRACT

A microfluidic device designed for electrochemical studies on a microliter scale has been utilized for the examination of impurity levels in ionic liquids (ILs). Halide impurities are common following IL synthesis, and this study demonstrates the ability to quantify low concentrations of halide in a range of ILs to levels of approximately 5 ppm, even in ILs not currently measurable using other methods such as ion chromatography. To validate the mixer device, the electrochemistry of ferrocene was also examined and compared with spectroscopic and bulk electrochemistry measurements. An automated "sample preparation, delivery, and calibration" method was developed, and the chip successfully used for linear sweep, cyclic voltammetry (under both quiescent and steady-state flowing conditions), square wave voltammetry, and differential pulse voltammetry. An effective method of electrochemically cleaning the electrodes is also presented.

8.
Transfusion ; 40(2): 240-4, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10686009

ABSTRACT

BACKGROUND: A parentage testing laboratory was asked to perform testing in a case of sexual assault that resulted in the conception of a child. Samples submitted to the laboratory included blood from the mother, the alleged father, and the fetus. CASE REPORT: DNA typing was used to determine if the suspect in this sexual assault was the father of the expected child. DNA extracted from these samples was subjected to both restriction fragment length polymorphism and polymerase chain reaction/short-tandem repeat analysis at a total of 13 genetic loci. Examination of DNA profiles for selected markers suggested that the fetus was triploid. Triploidy was confirmed through the use of fluorescent in situ hybridization of chromosomes, employing three chromosome-specific alpha satellite probes and fetal trophoblast nuclei. Statistical interpretation of the test results required identifying a method for calculation that would consider two transmitted paternal genes. Attempts to modify the standard method of calculating a paternity index were unsuccessful, because it was not possible to distinguish between dispermy and diandry as the mechanism of conception. Therefore, the likelihood ratio was calculated as the reciprocal of the random men not excluded value or the proportion of the population that possesses all of the paternal markers observed in the triploid fetus. CONCLUSION: Calculation of a likelihood ratio employing the exclusionary power of a collection of DNA markers appears to be the only method suitable for assigning weight to the significance of DNA matches between an alleged father and a child who is triploid.


Subject(s)
DNA/analysis , Fetus/metabolism , Paternity , Alleles , Heterozygote , Humans , In Situ Hybridization, Fluorescence , Likelihood Functions , Male , Ploidies , Polymorphism, Restriction Fragment Length
9.
Genet Test ; 4(4): 377-81, 2000.
Article in English | MEDLINE | ID: mdl-11216662

ABSTRACT

Experience performing prenatal genotyping for RHD has shown that consideration must be given to developing a molecular test capable of detecting recombination/gene conversion events involving the RHD and RHCE genes that can lead to erroneous results. Out of 50 prenatal RHD tests performed over the past 5 years, four samples were encountered that gave false-positive results. In only one of the tests, incorrect results were issued to the physician. In the other three instances, the erroneous nature of the test results was revealed through the analysis of multiple regions of the RHD gene and, more importantly, because the mother, and sometimes the father, were tested in parallel with the fetus. In an extension of the observations obtained from the prenatal testing program, a large panel of RhD-negative blood donors were subjected to molecular analysis of the RHD gene. Of 1,183 donors screened, 187 were found to phenotype as RhD negative. Of the 187 donors confirmed RhD negative serologically, 22 (11.8%) were found to retain remnants of the RHD gene that, depending upon the characteristics of the molecular assay performed, could lead to a false-positive result in a genotyping assay. On the basis of the experience presented here, it is recommended that any molecular RHD assay include an analysis of multiple areas of the RHD gene so as to allow for the detection of recombination/gene conversion events between the RHD and RHCE genes. Moreover, it is strongly recommended that the mother (at a minimum) and father be subjected to molecular analysis simultaneously with the fetus to confirm that the known phenotypes of the parent(s) are consistent with their respective genotypes.


Subject(s)
Prenatal Diagnosis/methods , Rh-Hr Blood-Group System/genetics , Exons/genetics , False Positive Reactions , Female , Fetus/cytology , Fetus/metabolism , Genotype , Glycoproteins/genetics , Humans , Male , Phenotype , Polymerase Chain Reaction , Recombination, Genetic/genetics , Rh-Hr Blood-Group System/immunology , Sensitivity and Specificity , Serology
10.
Anesth Analg ; 86(3): 579-83, 1998 Mar.
Article in English | MEDLINE | ID: mdl-9495419

ABSTRACT

UNLABELLED: Complex regional pain syndromes (CRPS) and neuropathic pain are often poorly controlled by conventional pharmacologic interventions. We administered 8-methyl-N-vanillyl-noneamide (capsaicin) at doses of 5%-10% to individuals with such disorders in this trial. Previous limitations to trials with larger-dose, topical concentrations of capsaicin included intense burning sensations experienced after application. To enable patients to tolerate the high concentrations, we first performed regional anesthesia. All patients reported at least some relief. Of 10 patients, 9 obtained substantial analgesia that lasted 1-18 wk. At Week 1 after therapy, the mean verbal analog scale (VAS) scores decreased from 8.0 to 3.0. At Week 4 after therapy, mean VAS score was 4.5. Analgesia lasted from < 1 wk (1 patient) to more than 50 wk (1 patient). Patients received one to eight treatments. With one exception, patients receiving more than one treatment obtained additional relief with subsequent treatment. Pain responsive to opioids was the only side effect of treatment. Large-dose capsaicin administered with regional anesthesia may effectively minimize refractory CRPS and neuropathic pain. A double-blind, placebo-controlled study in patients with bilateral peripheral neuropathy using epidural anesthesia with and without large-dose topical capsaicin is in progress. IMPLICATIONS: Sensory neuropathies are associated with many diseases. Pain from these disorders can produce greater disability than the primary disease processes themselves. Currently available therapies are limited. However, the intermittent application of large-dose topical capsaicin may provide significant pain relief, decrease chronic analgesic dependence, and decrease aggregate health care expenditures.


Subject(s)
Capsaicin/administration & dosage , Pain, Intractable/drug therapy , Administration, Topical , Hot Temperature , Humans , Nociceptors/drug effects , Reflex Sympathetic Dystrophy/drug therapy
11.
Acta Astronaut ; 41(4-10): 507-14, 1997.
Article in English | MEDLINE | ID: mdl-11541149

ABSTRACT

In fulfilling the National Aeronautics and Space Administration's (NASA) responsibility to encourage the fullest commercial use of space the Space Product Development (SPD) Program, within the Microgravity Research Program Office (MRPO) located at the Marshall Space Flight Center (MSFC) in Huntsville, Alabama, is managing an organization of Commercial Space Centers (CSC's) that have successfully employed methods for encouraging private industries to exploit the benefits of space-based research. Unique research opportunities of the space environment are being made available to private industry in an effort to develop new, competitive products; create jobs; and enhance the country's quality of life. Over 200 commercial research activities have been conducted in space by the CSC's and their industrial partners during the last several years. The success of this research is evidenced by the increasing amount of industrial participation in commercial microgravity research and the potential products nearing marketability.


Subject(s)
Space Flight/trends , Technology Transfer , Technology/trends , United States National Aeronautics and Space Administration/trends , Weightlessness , Biotechnology/economics , Biotechnology/organization & administration , Biotechnology/trends , Crystallography , Genetic Engineering , Industry , Lighting , Plant Physiological Phenomena , Plants, Genetically Modified , Space Flight/economics , Space Flight/organization & administration , Technology/economics , Technology/organization & administration , Technology, Pharmaceutical , United States , United States National Aeronautics and Space Administration/economics , United States National Aeronautics and Space Administration/organization & administration , Vacuum
12.
Paediatr Anaesth ; 7(2): 171-5, 1997.
Article in English | MEDLINE | ID: mdl-9188121

ABSTRACT

A thirteen-year-old girl with normokalaemic familial periodic paralysis (FPP) suffered life threatening upper airway obstruction secondary to tonsillopharyngitis resulting from infectious mononucleosis (IM). Emergency tonsillectomy was performed, but her postoperative course was complicated by persistent muscle weakness requiring a very prolonged period of artificial ventilation.


Subject(s)
Infectious Mononucleosis/surgery , Muscle Weakness/etiology , Paralyses, Familial Periodic/complications , Postoperative Complications , Tonsillectomy , Adolescent , Emergencies , Female , Humans , Infectious Mononucleosis/complications , Paralyses, Familial Periodic/diagnosis , Paralyses, Familial Periodic/drug therapy , Respiration, Artificial , Respiratory Insufficiency/etiology , Respiratory Insufficiency/therapy
13.
AJNR Am J Neuroradiol ; 17(7): 1205-10, 1996 Aug.
Article in English | MEDLINE | ID: mdl-8871700

ABSTRACT

PURPOSE: To determine whether unenhanced high-resolution T2-weighted fast spin-echo MR imaging provides an acceptable and less expensive alternative to contrast-enhanced conventional T1-weighted spin-echo MR techniques in the diagnosis of acoustic schwannoma. METHODS: We reviewed in a blinded fashion the records of 25 patients with pathologically documented acoustic schwannoma and of 25 control subjects, all of whom had undergone both enhanced conventional spin-echo MR imaging and unenhanced fast spin-echo MR imaging of the cerebellopontine angle/internal auditory canal region. The patients were imaged with the use of a quadrature head receiver coil for the conventional spin-echo sequences and dual 3-inch phased-array receiver coils for the fast spin-echo sequences. RESULTS: The size of the acoustic schwannomas ranged from 2 to 40 mm in maximum dimension. The mean maximum diameter was 12 mm, and 12 neoplasms were less than 10 mm in diameter. Acoustic schwannoma was correctly diagnosed on 98% of the fast spin-echo images and on 100% of the enhanced conventional spin-echo images. Statistical analysis of the data using the kappa coefficient demonstrated agreement beyond chance between these two imaging techniques for the diagnosis of acoustic schwannoma. CONCLUSIONS: There is no statistically significant difference in the sensitivity and specificity of unenhanced high-resolution fast spin-echo imaging and enhance T1-weighted conventional spin-echo imaging in the detection of acoustic schwannoma. We believe that the unenhanced high-resolution fast spin-echo technique provides a cost-effective method for the diagnosis of acoustic schwannoma.


Subject(s)
Magnetic Resonance Imaging/methods , Neuroma, Acoustic/diagnosis , Adult , Aged , Aged, 80 and over , Cerebellopontine Angle , Ear, Inner , Health Care Costs , Humans , Magnetic Resonance Imaging/economics , Middle Aged , Observer Variation
14.
Anaesthesia ; 50(12): 1077-9, 1995 Dec.
Article in English | MEDLINE | ID: mdl-8546291

ABSTRACT

We report a case of subcutaneous emphysema following multiple attempts to cannulate both subclavian veins for pacemaker insertion. Initial bilateral pneumothoraces were complicated by subcutaneous emphysema which became so severe that respiration and cardiac output became seriously impaired. The insertion of a single large bore subcutaneous drain produced a dramatic improvement. The aetiology, complications and management of tension subcutaneous emphysema are discussed.


Subject(s)
Catheterization, Central Venous/adverse effects , Drainage/methods , Subcutaneous Emphysema/therapy , Aged , Humans , Male , Pacemaker, Artificial , Pneumothorax/complications , Subcutaneous Emphysema/etiology
16.
J Relig Health ; 34(4): 301-12, 1995 Dec.
Article in English | MEDLINE | ID: mdl-24264479

ABSTRACT

Religion as a personal coping resource used by parents of infants and toddlers with disabilities has received some attention in recent literature. This exploratory study involved indepth interviews of 12 parents who had children with disabilities ranging in age from 15 months to 30 years. The ways in which religion can be used as a coping resource across the life-cycle are exemplified through excerpts from these interviews. Prayer, church attendance, and specific religious beliefs were identified as sources of support which helped some parents feel a growing sense of hope and strength. Suggestions for future research are discussed.

17.
Transfusion ; 34(5): 412-4, 1994 May.
Article in English | MEDLINE | ID: mdl-8191566

ABSTRACT

BACKGROUND: DNA profiles from variable number of tandem repeat (VNTR) loci typically are composed of two bands, one derived from each member of the homologous pair of chromosomes. DNA profiles composed of more than two bands result from mutations, and the question arises as to the mechanism underlying these unusual multi-banded DNA profiles. STUDY DESIGN AND METHODS: An alleged father in a paternity test was found to have a five-banded DNA profile at the D10S28 locus when his DNA was subjected to single-locus restriction fragment length polymorphism mapping with the restriction enzyme Pvu II. RESULTS: Several results suggest that this complex DNA profile is the result of several single-base changes within the VNTR locus. First, there was no evidence of partial digestion of the DNA with Pvu II. Furthermore, the multi-banded allele happened, in this case, to be transmitted to the child, who also showed a five-banded pattern composed of four bands inherited from the alleged father and one band inherited from the mother. Second, digestion of this DNA with Hae III resulted in the visualization of just two bands at the D10S28 locus. CONCLUSION: The results confirm the notion that mutations at VNTR loci are not always the result of additions or deletions of tandem repeats, but that they can also involve single-base substitutions either within or flanking VNTR loci that give rise to atypical DNA profiles and new alleles at the locus.


Subject(s)
Chromosome Banding , DNA/genetics , DNA/blood , DNA Fingerprinting , Female , Humans , Leukocytes/chemistry , Male , Parents , Repetitive Sequences, Nucleic Acid
18.
Eur J Immunol ; 24(4): 952-8, 1994 Apr.
Article in English | MEDLINE | ID: mdl-8149964

ABSTRACT

Enhanced expression of epidermal growth factor receptor (EGFR) occurs on a variety of malignant tissues thus making anti-EGFR antibodies possible agents for the diagnosis and therapy of human tumors. Standard hybridoma technology has been used successfully to isolate anti-EGFR antibodies from immunized mice and rats. This report demonstrates that phage-antibody libraries are an alternative, and more versatile, method for isolating antibodies from immunized mice. Anti-EGFR antibodies were isolated from phage-antibody libraries constructed not only from the spleen of an immunized mouse but also from the draining lymph node of an immunized mouse and from in vitro immunized mouse cells. Two of the single-chain Fv isolated from the phage-antibody libraries were engineered to create partially humanized whole antibody molecules.


Subject(s)
Bacteriophages/genetics , ErbB Receptors/immunology , Immunoglobulin Fragments/isolation & purification , Neoplasms/immunology , Recombinant Fusion Proteins/isolation & purification , Amino Acid Sequence , Animals , Antibodies, Monoclonal/immunology , Antibody Affinity , Bacteriophages/immunology , Base Sequence , Gene Library , Humans , Immunization , Immunoglobulin Fragments/chemistry , Immunoglobulin Fragments/genetics , Mice , Mice, Inbred CBA , Molecular Sequence Data
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