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CO
Kinds of CO Terms modified by CO Selected AbstractsChemInform Abstract: Catalytic Radical Addition of Carbonyl Compounds to Alkenes by Mn(II)/CO(II)/O2 System.CHEMINFORM, Issue 30 2002Kouji Hirase Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] MOCVD n-InAs thin layers compared with MBE samples , far infrared magnetophotoconductivityPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 2 2003Z. Romanowski Abstract A comparison of the properties of n-InAs thin layers grown by the MOCVD method and, reported elsewhere, similar samples obtained by MBE processing is presented. The measured photoconductivity spectra exhibit a variety of peaks, among them , very narrow peaks (with the halfwidths of ,20 mT) due to cyclotron resonance (CR) and impurity cyclotron resonance (ICR) transitions. Measurements with tilted magnetic field allowed to correlate peaks with the CR or ICR transitions in the different sample regions: with 2D and 3D electron gas. The detailed analysis shows, that we observe peaks with positions more strongly dependent on the magnitude of the tilt angle than the standard 1/cos,, (, is a sample tilt angle) dependence. These lines were not observed in MBE samples. Results are discussed in terms of a correspondence between the distribution of carriers and the spatial structure of the sample. As a result one can state, that the MOCVD samples seem to have the same quality as samples obtained by the MBE method. [source] Introduction of Clusterin Gene into Human Renal Cell Carcinoma Cells Enhances Their Resistance to Cytotoxic Chemotherapy through Inhibition of Apoptosis both in vitro and in vivoCANCER SCIENCE, Issue 11 2001Isao Hara Recent studies have revealed the powerful antiapoptotic activity of clusterin in various malignant tumors; however, the significance of clusterin expression in the acquisition of a resistant phenotype against several kinds of treatment in human renal cell carcinoma (RCC) has not been well characterized. We, therefore, transfected the clusterin cDNA into RCC ACHN cells, that scarcely express clusterin protein, to examine whether overexpression of clusterin inhibits chemotherapy-induced apoptosis both in vitro and in vivo. Although no significant differences were observed in the in vitro growth rates between clusterin-transfected ACHN (ACHN/CL) and the vector only-transfected cell line (ACHN/Co), ACHN/CL exhibited high resistance to cisplatin treatment compared with ACHN/Co, with a greater than 5-fold higher IC50 through the inhibition of apoptotic cell death, which was demonstrated by DNA fragmentation analysis and western blotting of PARP protein. Moreover, intravenous administration of cisplatin into athymic nude mice bearing ACHN/CL tumors resulted in 2- to 3-times faster tumor growth compared with ACHN/Co tumors. These findings suggest that clusterin overexpression helps confer a chemoresistant phenotype through inhibition of apoptosis in human RCC cells. [source] Solute movement through intact columns of cryoturbated Upper ChalkHYDROLOGICAL PROCESSES, Issue 13 2008M. Mahmood-ul-Hassan Abstract Cryoturbated Upper Chalk is a dichotomous porous medium wherein the intra-fragment porosity provides water storage and the inter-fragment porosity provides potential pathways for relatively rapid flow near saturation. Chloride tracer movement through 43 cm long and 45 cm diameter undisturbed chalk columns was studied at water application rates of 0·3, 1·0, and 1·5 cm h,1. Microscale heterogeneity in effluent was recorded using a grid collection system consisting of 98 funnel-shaped cells each 3·5 cm in diameter. The total porosity of the columns was 0·47 ± 0·02 m3 m,3, approximately 13% of pores were , 15 µm diameter, and the saturated hydraulic conductivity was 12·66 ± 1·31 m day,1. Although the column remained unsaturated during the leaching even at all application rates, proportionate flow through macropores increased as the application rate decreased. The number of dry cells (with 0 ml of effluent) increased as application rate decreased. Half of the leachate was collected from 15, 19 and 22 cells at 0·3, 1·0, 1·5 cm h,1 application rates respectively. Similar breakthrough curves (BTCs) were obtained at all three application rates when plotted as a function of cumulative drainage, but they were distinctly different when plotted as a function of time. The BTCs indicate that the columns have similar drainage requirement irrespective of application rates, as the rise to the maxima (C/Co) is almost similar. However, the time required to achieve that leaching requirement varies with application rates, and residence time was less in the case of a higher application rate. A two-region convection,dispersion model was used to describe the BTCs and fitted well (r2 = 0·97,0·99). There was a linear relationship between dispersion coefficient and pore water velocity (correlation coefficient r = 0·95). The results demonstrate the microscale heterogeneity of hydrodynamic properties in the Upper Chalk. Copyright © 2007 John Wiley & Sons, Ltd. [source] Comparison of Impedance Cardiography to Direct Fick and Thermodilution Cardiac Output Determination in Pulmonary Arterial HypertensionCONGESTIVE HEART FAILURE, Issue 2004Gordon L. Yung MD Cardiac output (CO) is an important diagnostic and prognostic tool for patients with ventricular dysfunction. Pulmonary hypertension patients undergo invasive right heart catheterization to determine pulmonary vascular and cardiac hemodynamics. Thermodilution (TD) and direct Fick method are the most common methods of CO determination but are costly and may be associated with complications. The latest generation of impedance cardiography (ICG) provides noninvasive estimation of CO and is now validated. The purpose of this study was to compare ICG measurement of CO to TD and direct Fick in pulmonary hypertension patients. Thirty-nine enrolled patients were analyzed: 44% were male and average age was 50.8±17.4 years. Results for bias and precision of cardiac index were as follows: ICG vs. Fick (,0.13 L/min/m2 and 0.46 L/min/m2), TD vs. Fick (0.10 L/min/m2 and 0.41 L/min/m2), ICG vs. TD (respectively, with a 95% level of agreement between ,0.72 and 0.92 L/min/m2; CO correlation of ICG vs. Fick, TD vs. Fick, and ICG vs. TD was 0.84, 0.89, and 0.80, respectively). ICG provides an accurate, useful, and cost-effective method for determining CO in pulmonary hypertension patients, and is a potential tool for following responses to therapeutic interventions. [source] Systemic nitric oxide clamping in normal humans guided by total peripheral resistanceACTA PHYSIOLOGICA, Issue 2 2010J. A. Simonsen Abstract Aim:, We wanted to stabilize the availability of nitric oxide (NO) at levels compatible with normal systemic haemodynamics to provide a model for studies of complex regulations in the absence of changes in NO levels. Methods:, Normal volunteers (23,28 years) were infused i.v. with the nitric oxide synthase (NOS) inhibitor NG -nitro- l -arginine methyl ester (l -NAME) at 0.5 mg kg,1 h,1. One hour later, the NO donor sodium nitroprusside (SNP) was co-infused in doses eliminating the haemodynamic effects of l -NAME. Haemodynamic measurements included blood pressure (MABP) and cardiac output (CO) by impedance cardiography. Results:,l -NAME increased MABP and total peripheral resistance (TPR, 1.02 ± 0.05 to 1.36 ± 0.07 mmHg s mL,1, mean ± SEM, P < 0.001). With SNP, TPR fell to a stable value slightly below control (0.92 ± 0.05 mmHg s mL,1, P < 0.05). CO decreased with l -NAME (5.8 ± 0.3 to 4.7 ± 0.3 L min,1, P < 0.01) and returned to control when SNP was added (6.0 ± 0.3 L min,1). A decrease in plasma noradrenaline (42%, P < 0.01) during l -NAME administration was completely reversed by SNP. Plasma renin activity decreased during l -NAME administration and returned towards normal after addition of SNP. In contrast, plasma aldosterone was increased by l -NAME and remained elevated. Conclusions:, Concomitant NOS inhibition and NO donor administration can be adjusted to maintain TPR at control level for hours. This approach may be useful in protocols in which stabilization of the peripheral supply of NO is required. However, the dissociation between renin and aldosterone secretion needs further investigation. [source] Stroke volume decreases during mild dynamic and static exercise in supine humansACTA PHYSIOLOGICA, Issue 2 2009M. Elstad Abstract Aim:, The contributions of cardiac output (CO) and total peripheral resistance to changes in arterial blood pressure are debated and differ between dynamic and static exercise. We studied the role stroke volume (SV) has in mild supine exercise. Methods:, We investigated 10 healthy, supine volunteers by continuous measurement of heart rate (HR), mean arterial blood pressure, SV (ultrasound Doppler) and femoral beat volume (ultrasound Doppler) during both dynamic mild leg exercise and static forearm exercise. This made it possible to study CO, femoral flow (FF) and both total and femoral peripheral resistance beat-by-beat. Results:, During a countdown period immediately prior to exercise, HR and mean arterial pressure increased, while SV decreased. During mild supine exercise, SV decreased by 5,8%, and most of this was explained by increased mean arterial pressure. Dynamic leg exercise doubled femoral beat volume, while static hand grip decreased femoral beat volume by 18%. FF is tightly regulated according to metabolic demand during both dynamic leg exercise and static forearm exercise. Conclusion:, Our three major findings are, firstly, that SV decreases during both dynamic and static mild supine exercise due to an increase in mean arterial pressure. Secondly, femoral beat volume decreases during static hand grip, but FF is unchanged due to the increase in HR. Finally, anticipatory responses to exercise are apparent prior to both dynamic and static exercise. SV changes contribute to CO changes and should be included in studies of central haemodynamics during exercise. [source] Twenty-four-hour non-invasive monitoring of systemic haemodynamics and cerebral blood flow velocity in healthy humansACTA PHYSIOLOGICA, Issue 1 2002M. DIAMANT ABSTRACT Acute short-term changes in blood pressure (BP) and cardiac output (CO) affect cerebral blood flow (CBF) in healthy subjects. As yet, however, we do not know how spontaneous fluctuations in BP and CO influence cerebral circulation throughout 24 h. We performed simultaneous monitoring of BP, systemic haemodynamic parameters and blood flow velocity in the middle cerebral artery (MCAV) in seven healthy subjects during a 24-h period. Finger BP was recorded continuously during 24 h by Portapres and bilateral MCAV was measured by transcranial Doppler (TCD) during the first 15 min of every hour. The subjects remained supine during TCD recordings and during the night, otherwise they were seated upright in bed. Stroke volume (SV), CO and total peripheral resistance (TPR) were determined by Modelflow analysis. The 15 min mean value of each parameter was assumed to represent the mean of the corresponding hour. There were no significant differences between right vs. left, nor between mean daytime vs. night time MCAV. Intrasubject comparison of the twenty-four 15-min MCAV recordings showed marked variations (P < 0.001). Within each single 15-min recording period, however, MCAV was stable whereas BP showed significant short-term variations (P < 0.01). A day,night difference in BP was only observed when daytime BP was evaluated from recordings in the seated position (P < 0.02), not in supine recordings. Throughout 24 h, MCAV was associated with SV and CO (P < 0.001), to a lesser extent with mean arterial pressure (MAP; P < 0.005), not with heart rate (HR) or TPR. These results indicate that in healthy subjects MCAV remains stable when measured under constant supine conditions but shows significant variations throughout 24 h because of activity. Moreover, changes in SV and CO, and to a lesser extent BP variations, affect MCAV throughout 24 h. [source] Calcaneal ultrasonometry in patients with Charcot osteoarthropathy and its relationship with densitometry in the lumbar spine and femoral neck and with markers of bone turnoverDIABETIC MEDICINE, Issue 6 2001A. Jirkovská Abstract Aims To assess calcaneal ultrasonometry in Charcot osteoarthropathy (CO) and to compare it with densitometry measured by dual energy X-ray absorptiometry (DEXA) and with bone remodelling markers. Patients and methods A group of 16 diabetic patients in the acute stage of CO with a mean age (± sd) of 51 ± 13 years was compared with 26 sex- and age-matched control subjects. Both calcaneal quantitative ultrasound (QUS) parameter stiffness and bone mineral density (BMD) measured in lumbar spine and femoral neck by DEXA were compared. Collagen type I cross-linked C-telopeptides (ICTP) were used for assessment of bone resorption. Results Patients with acute CO had significantly lower stiffness of the calcaneus in the Charcot and non-Charcot foot (both P < 0.001) and significantly lower femoral neck BMD (P < 0.05) in comparison with the control group. The T-score of stiffness was significantly lower in the Charcot foot compared with the non-Charcot foot (,3.00 ± 1.39 vs. ,2.36 ± 1.12; P < 0.01) and significantly lower than the mean T-score of BMD in the lumbar spine (,0.57 ± 1.28; P < 0.001) and femoral neck (,1.58 ± 1.24; P < 0.05). A significant difference in ICTP (8.49 ± 4.37 vs. 3.92 ± 2.55 ng/ml; P < 0.001) between patients with CO and the control group was found, and a significant correlation was demonstrated between ICTP and the T-score of stiffness (r = ,0.73; P < 0.01). Conclusion The lower calcaneal QUS parameter stiffness in the Charcot foot in comparison with the control group, with the non-Charcot foot and with BMD in the lumbar spine and femoral neck, and its association with increased bone resorption indicate that calcaneal ultrasonometry may be useful in diagnosing the acute stage of CO and in assessing the risk of foot fracture. Diabet. Med. 18, 495,500 (2001) [source] Inter-observer agreement for multichannel intraluminal impedance,pH testingDISEASES OF THE ESOPHAGUS, Issue 7 2010K. Ravi SUMMARY Twenty-four-hour ambulatory multichannel intraluminal impedance (MII),pH detects both acid and nonacid reflux (NAR). A computer-based program (AutoscanÔ, Sandhill Scientific, Highlands Ranch, CO, USA) automates the detection of reflux episodes, increasing the ease of study interpretation. Inter-observer agreement between multiple reviewers and with AutoscanÔ for the evaluation of significant NAR with MII,pH has not been studied in the adult population. Twenty MII,pH studies on patients taking a proton pump inhibitor twice daily were randomly selected. AutoscanÔ analyzed all studies using the same pre-programmed parameters. Four reviewers interpreted the MII,pH studies, adding or deleting reflux episodes detected by AutoscanÔ. Positive studies for NAR and total reflux episodes were based on published criteria. Cohen's kappa statistic (,) evaluated inter-observer agreement between reviewers and AutoscanÔ analysis. The average , for pathologic NAR between reviewers was 0.57 (0.47,0.70), and between reviewers and AutoscanÔ was 0.56 (0.4,0.8). When using the total reflux episode number as a marker for pathologic reflux (acid and NAR), the , score was 0.72 (0.61,0.89) between reviewers, and 0.74 (0.53,0.9) when evaluating total reflux episodes. Two reviewers agreed more often with each other and with AutoscanÔ on the number of NAR episodes, while the other two reviewers agreed with each other, but did not agree with either AutoscanÔ or the first two reviewers. Inter-observer agreement between reviewers and AutoscanÔ for detecting pathologic NAR is moderate, with reviewers either excluding more of the AutoscanÔ-defined events or excluding fewer events and therefore agreeing with AutoscanÔ. [source] Dyslexia and psycho-social functioning: an exploratory study of the role of self-esteem and understandingDYSLEXIA, Issue 4 2009Melody M. Terras Abstract Individuals with dyslexia may have lower self-esteem and exhibit more emotional and behavioural difficulties than those without reading problems. However, the nature of any relationship between self-esteem and psychopathology remains unknown. This exploratory study assessed levels of self-esteem using the Self-Perception Profile for Children (Manual for the Self-Perception Profile for Children. University of Denver, CO: Denver; 1985) and psycho-social adjustment using the Strengths and Difficulties Questionnaire (J. Child Psychol. Psychiatry, 1997; 38: 581,586) and examined child and parent understanding, attitudes and the perceived impact of reading difficulties on daily life. Sixty-eight children assessed as dyslexic on the basis of discrepancy scores (mean age 11.2 years; 44 male), and their parents, participated. No global self-esteem deficit was found, but the mean score for both child and parent-rated scholastic competence was significantly lower than that of the general population. Rates of social, emotional and behavioural difficulties were significantly higher than in the general population and were correlated with self-esteem. For children who had high global self-worth, both children and their parents had more positive attitudes towards their reading difficulties and were less likely to perceive a negative impact on relationships. The association between academic self-esteem and emotional symptoms is consistent with the proposed link between dyslexia and internalizing difficulties. Good self-esteem and a good understanding of dyslexia may help children avoid some of these difficulties. Further research with larger more representative samples is necessary as understanding the factors that promote successful psycho-social adjustment is essential to the development of effective prevention and intervention strategies. Copyright © 2009 John Wiley & Sons, Ltd. [source] Stability Enhancement of All-Solid-State H+ ISEs with Cross-Linked Silicon-Urethane MatricesELECTROANALYSIS, Issue 8 2005Nak-Hyun Kwon Abstract An all-solid-state hydrogen-ion-selective electrode (ASHISE) was fabricated using the polymer hybrid membrane. Polymer membranes composed of Tecoflex polyurethane (TPU), polyvinyl chloride (PVC), silicon rubber (SR), and additives (KTpClPB, DOA, and TDDA) were cast on a carbon rod. The TPU/SR hybrid membrane exhibited a longer lifetime and a higher sensitivity in the sensing of the H+ ion compared to conventional TPU/PVC and PVC/SR hybrid membranes. Moreover, the addition of SiCl4 to TPU-based matrices enhanced the potentiometric response and ISE stability, due to the chemical bonding between Si and CO in urethane, in which the cross-linking configuration was confirmed by DSC, FT-IR, and XPS experiments. TPU/SR membranes containing SiCl4 were rendered more stable and showed a pH response over a wide range (i.e., pH,2,11.5) with the slope of 60±2,mV/pH for more than four months. The ASHISE exhibited a small interfering potential variation in the wide range of the salt concentration (from 1.0×10,6,M up to 0.1,M). The ASHISE showed a result comparable to a commercial clinical blood analyzer. [source] Analysis of chicken and turkey ovalbumins by microchip electrophoresis combined with exoglycosidase digestionELECTROPHORESIS, Issue 18 2003Xiuli Mao Abstract The polypeptide and carbohydrate patterns of two glycoproteins, chicken ovalbumin (CO) and turkey ovalbumin (TO), were analyzed by microchip electrophoresis (ME), following digestion with proteases and exoglycosidases. Glycopeptides derived from ovalbumin were obtained by digestion with Pronase, followed by dialysis, and then separated by ME. Using CO as model, the method was developed to deduce the structure of glycans from glycoproteins by comparing the electropherograms of glycopeptides with and without digestion of exolycosidases. Applying the same approach, the structure of oligosaccharides linked to TO was determined. TO was found to contain high-mannose type oligosaccharides and oligosaccharides with terminal N -acetylglucosamine residues. The complete primary analysis of CO and TO by ME described in this paper provides a basis for an analysis of glycoproteins with an integrated microfluidic chip. [source] Where to now with carbon monoxide poisoning?EMERGENCY MEDICINE AUSTRALASIA, Issue 2 2004Carlos D Scheinkestel Abstract The controversy regarding the role of hyperbaric oxygen (HBO) in the treatment of carbon monoxide (CO) poisoning has been re-ignited following the publication of a further randomized controlled trial by Weaver et al., the results of which appear to conflict with our findings. Comparative analysis suggests that the apparent outcome differences may be secondary to the design, analysis and interpretation of the results of the two studies. Following careful analysis of these two papers and further results from a study by Raphael et al on 385 CO-poisoned patients, we can still find no convincing evidence favouring HBO therapy. Pending further research to determine optimal oxygen therapy for CO-poisoning, current therapy should involve stratifying patients for risk of a poor outcome. This stratification may be aided by the evolving availability of biochemical markers of brain injury and the finding that patients with transient loss of consciousness and poor performance on neuropsychological tests of the supervisory attention system are at higher risk of neuropsychological sequelae. We propose that those patients most at risk be admitted and receive more prolonged normobaric oxygen therapy whilst those with more minor CO-poisoning should be provided with normobaric oxygen of no less than 6 h duration and certainly until sign and symptom free. [source] A comparison of the effectiveness of group-based and pharmacy-led smoking cessation treatment in GlasgowADDICTION, Issue 2 2009Linda Bauld ABSTRACT Aim To compare the characteristics and outcomes of users accessing pharmacy and group-based smoking treatment. Design Observational study of administrative information linked with survey data. Setting Glasgow, Scotland. Participants A total of 1785 service users who set a quit date between March and May 2007. Intervention Smoking treatment services based in pharmacies providing one-to-one support, and in the community offering group support. Measurements Routine monitoring data included information about basic demographic characteristics, deprivation category of residence, nature of intervention and smoking status at 4-week follow-up determined by carbon monoxide (CO) readings ,10. These data were supplemented by information about socio-economic status and smoking-related behaviours obtained from consenting service recipients by treatment advisers. Findings In the pharmacy-based service 18.6 % of users (n = 1374) were CO-validated as a quitter at 4 weeks, compared with 35.5 % (n = 411) in the group-based service. In a multivariate model, restricted to participants (n = 1366) with data allowing adjustment for socio-demographic and behavioural characteristics and including interaction terms, users who accessed the group-based services were almost twice as likely (odds ratio 1.980; confidence interval 1.50,2.62) as those who used pharmacy-based support to have quit smoking at 4-week follow-up. Conclusions Specialist-led group-based services appear to have higher quit rates than one-to-one services provided by pharmacies but the pharmacy services treat many more smokers. More research is needed to determine what can be done to bring the success rates of pharmacy services up to those of specialist-led groups and how to expand access to group-based services. [source] Evaluating the validities of different DSM-IV-based conceptual constructs of tobacco dependence,ADDICTION, Issue 7 2008Peter S. Hendricks ABSTRACT Aim To compare the concurrent and predictive validities of two subsets of DSM-IV criteria for nicotine dependence (tolerance and withdrawal; withdrawal; difficulty controlling use; and use despite harm) to the concurrent and predictive validity of the full DSM-IV criteria. Design Analysis of baseline and outcome data from three randomized clinical trials of cigarette smoking treatment. Setting San Francisco, California. Participants Two samples of cigarette smokers (n = 810 and 322), differing with regard to baseline characteristics and treatment received, derived from three randomized clinical trials. Measurements DSM-IV nicotine dependence criteria were measured at baseline with a computerized version of the Diagnostic Interview Schedule for DSM-IV (DIS-IV). Additional baseline measures included the Fagerström Test of Nicotine Dependence (FTND), number of cigarettes smoked per day, breath carbon monoxide (CO) level, the Minnesota Nicotine Withdrawal Scale (MNWS), the Michigan Nicotine Reinforcement Questionnaire (M-NRQ) and the Profile of Mood States (POMS). Seven-day point-prevalence abstinence was assessed at week 12. Findings Full DSM-IV criteria displayed greater concurrent validity than either of the two subsets of criteria. However, DSM-IV symptoms accounted for only a nominal amount of the variance in baseline smoking-related characteristics and were unrelated to smoking abstinence at week 12. Cigarettes smoked per day was the only significant predictor of abstinence at week 12. Conclusions Although the findings do not provide a compelling alternative to the full set of DSM-IV nicotine dependence criteria, its poor psychometric properties and low predictive power limit its clinical and research utility. [source] Unrecognized Misplacement of Endotracheal Tubes in a Mixed Urban to Rural Emergency Medical Services SettingACADEMIC EMERGENCY MEDICINE, Issue 9 2003Michael E. Jemmett MD Abstract Objective: To determine the rate of unrecognized endotracheal tube misplacement when performed by emergency medical services (EMS) personnel in a mixed urban and rural setting. Methods: The authors conducted a prospective, observational analysis of out-of-hospital endotracheal intubations (EIs) performed by EMS personnel serving a mixed urban, suburban, and rural population. From July 1, 1998, to August 30, 1999, emergency physicians assessed and recorded the position of out-of-hospital EIs using auscultation, direct laryngoscopy, infrared CO 2 detectors, esophageal detector devices, and chest x-ray. The state EMS database also was reviewed to determine the number of EIs involving patients transported to the authors' medical center and paramedic assessment of success for these encounters. Results: A total of 167 out-of-hospital EIs were recorded, of which 136 (81%) were deemed successful by EMS personnel. Observational forms were completed for 109 of the 136 patients who arrived intubated to the emergency department. Of the studied patients, 12% (13 of 109) were found to have misplaced endotracheal tubes. For the patients with unrecognized improperly placed tubes, 9% (10 of 109) were in the esophagus, 2% (2 of 109) were in the right main stem, and 1% (1 of 109) were above the cords. Paramedics serving urban and suburban areas did not perform significantly better (p < 0.05) than intermediate-level providers serving areas that are more rural. Conclusions: The incidence of unrecognized misplacement of endotracheal tubes by EMS personnel may be higher than most previous studies, making regular EMS evaluation and the out-of-hospital use of devices to confirm placement imperative. The authors were unable to show a difference in misplacement rates based on provider experience or level of training. [source] Gene expression in caged fish as a first-tier indicator of contaminant exposure in streamsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2005Aaron P. Roberts Abstract The development of sensitive, biologically based indicators of contaminant exposure (i.e., biomarkers) is an ongoing topic of research. These indicators have been proposed as a first-tier method of identifying contaminant exposure. The primary objective of this research was to implement a biomarker-based method of exposure assessment using caged fish and real-time reverse-transcriptase polymerase chain reaction (rtRT-PCR) measurements of gene expression. Primers were developed for the CYPIA, metallothionein, and vitellogenin genes in rainbow trout (Oncorhynchyus mykiss), cutbow trout (Oncorhynchyus clarkii × mykiss), and Atlantic salmon (Salmo salar). Each of these genes has been shown to respond specifically to planar aromatic compounds, heavy metals, and environmental estrogens, respectively. Juvenile fish were placed in cages and exposed in situ at reference and contaminated sites on the Cache la Poudre River (CO, USA), the Arkansas River (CO, USA), the St. John River (NB, Canada), and two urban creeks near Dayton (OH, USA). Quantitative gene expression was determined using rtRT-PCR. Biomarker expression profiles were obtained that demonstrated differences in CYP1A, metallothionein, and vitellogenin mRNA production unique to each site, indicating that specific types of compounds were bioavailable and present in sufficient concentrations to elicit transcriptional responses in the organism. These findings support the use of a biomarker-based approach to exposure identification and assessment. [source] Bayesian analysis of dynamic factor models: an application to air pollution and mortality in São Paulo, BrazilENVIRONMETRICS, Issue 6 2008T. Sáfadi Abstract The Bayesian estimation of a dynamic factor model where the factors follow a multivariate autoregressive model is presented. We derive the posterior distributions for the parameters and the factors and use Monte Carlo methods to compute them. The model is applied to study the association between air pollution and mortality in the city of São Paulo, Brazil. Statistical analysis was performed through a Bayesian analysis of a dynamic factor model. The series considered were minimal temperature, relative humidity, air pollutant of PM10 and CO, mortality circulatory disease and mortality respiratory disease. We found a strong association between air pollutant (PM10), Humidity and mortality respiratory disease for the city of São Paulo. Copyright © 2007 John Wiley & Sons, Ltd. [source] The meta-analysis of the Italian studies on short-term effects of air pollution (MISA): old and new issues on the interpretation of the statistical evidencesENVIRONMETRICS, Issue 3 2007Pierantonio Bellini Abstract The second meta-analysis of the Italian studies on short-term health effects of air pollution, known as MISA-2, was based on daily time series of indicators of both pollution and of health outcomes. It covered 15 cities during 1996,2002 for a total population of approximately nine millions. Health outcomes included mortality for natural causes, for respiratory diseases and for cardiovascular conditions, as well as hospital admissions for respiratory, cardiac and cerebrovascular diseases. Pollutants considered in univariate analyses were sulphur dioxide (SO2), nitrogen oxide (NO2), carbon monoxide (CO), suspended particulate matter (SPM) measuring less than 10,µm diameter (PM10) and ozone (O3, limited to the summer period). Results, including risk estimates, have been largely confirmatory of findings obtained in previous large meta-analytic studies carried out in North America and in Europe. A full report in Italian is available. The present contribution summarises the results of MISA-2 and addresses three major issues regarding their interpretation: robustness of the causal inferential process, the role of specific air pollutants and the reliability of risk estimates. The former issue is stressed according to Bradford Hill's criteria and the conclusion is reached that at least for the association of air pollution with an increase in mortality the evidence for causality is strong. Assessing the role of each air pollutant is problematic: there is some evidence that the effects of PM10 are partly confounded by other pollutants, but PM10 may not be the best indicator of the role of air SPM (routine measures of PM2.5 have not been introduced in Italy). As for risk estimates, the per cent increase in risk of mortality for unit increase in PM10 concentration, measured in MISA-2, is remarkably similar to estimates in other studies and there is indication for linearity of the dose,response relationship. Copyright © 2007 John Wiley & Sons, Ltd. [source] Spatial-temporal model for ambient air pollutants in the state of KuwaitENVIRONMETRICS, Issue 7 2006Fahimah A. Al-Awadhi Abstract In this paper we consider dynamic Bayesian models for four different pollutants: nitric oxide(NO), carbon monoxide(CO), sulphur dioxide(SO2) and non-methane hydrocarbon (NCH4) recorded daily in six different stations in Kuwait from 1999 to 2002. The structure of the models depends on time, space and pollutants dependencies. The approach strives to incorporate the uncertainty of the covariance structure into simulated models and final inference; therefore, hierarchical Bayesian model is applied. Association between level of pollutants and different meteorological variables, such as wind speed, wind directions, temperature and humidity are considered. The models will decompose into two main components: a deterministic part to represent the observed components term and a stochastic term to represent the unobservable components. Our analysis will start with basic model and gradually increase its complexity. At each stage the efficiency of the model will be measured. The resulting models subsequently are tested by comparing the output terms and by comparing and the predictions with the real observations. Copyright © 2006 John Wiley & Sons, Ltd. [source] Data analysis of environmental air pollutant monitoring systems in EuropeENVIRONMETRICS, Issue 6 2004Kristina Voigt Abstract Public access to information about the environment is being strengthened across Europe. The concept of public's right to information gives the basis for the access to environmental information. In this paper the quality of air pollutant monitoring systems in the 15 European member states is analyzed. For pragmatic reasons only the capitals are looked upon. Comprehensive data on environmental monitoring programs concerning air pollutants like ozone (O3), nitrogen dioxide (NO2), nitrogen oxide (NO), carbon dioxide (CO2) and carbon monoxide (CO), and sometimes suspended dust, benzene and other environmental chemicals are available on the free Internet. As different monitoring information systems exist in the European member states a comparison of these systems with their pros and cons is of great interest to the public. Environmental air pollutant monitoring systems in the capitals of the 15 EEC member countries (objects) are evaluated by applying 5 evaluation criteria for the differentiation of these systems. The scores run from 0,=,insufficient, 1,=,medium, to 2,=,excellent. Different data-analysis methods will be applied. As order theory is still not sufficiently presented in the scientific literature, a short overview about the so-called Hasse diagram technique and POSAC method is outlined. In several steps the data-matrix is analyzed coming to the conclusion that all methods (additionally PCA is used) identify one criterion as specifically important. Not unexpected, each method has its own advantage. The aim of this data-analysis is the evaluation of the publicly available air quality monitoring systems in Europe with their pros and cons. This might help the interested public to find and understand the information given on the Internet. Furthermore our evaluation approach might give some recommendations for an improvement of the air quality monitoring systems. Copyright © 2004 John Wiley & Sons, Ltd. [source] A randomized, double-blind, placebo-controlled clinical evaluation of a nicotine sublingual tablet in smoking cessationADDICTION, Issue 8 2000Mats Wallström Aims. Evaluation of the clinical efficacy and safety of a nicotine 2-mg sublingual tablet in smoking cessation. Design. A randomized, double-blind, placebo-controlled study of smokers using the 2-mg tablet for 3-6 months with follow-up to 12 months. Dosing was established according to baseline nicotine dependence, scored on the Fagerström Tolerance Questionnaire (FTQ): FTQ , 7, two tablets/hour (maximum 40/day); FTQ < 7, one tablet/hour (maximum 20/day). Setting. Smoking cessation programme in a department of oral and maxillofacial surgery. Participants. A total of 247 adult smokers, smoking , 10 cigarettes/day for , 3 years, of whom 123 received active and 124 placebo treatment. The study was powered to detect difference at 6 months. Measurements. Efficacy and safety were evaluated at 6 weeks and 3, 6 and 12 months. Self-reported abstinence was verified by exhaled CO < 10 p.p.m. Findings. Success rates for complete abstinence (no slips after 2 weeks) for active vs. placebo were 50% vs. 29% at 6 weeks, 42% vs. 23% at 3 months, 33% vs. 18% at 6 months and 23% vs. 15% at 12 months ( p < 0.001, 0.001, 0.005 and p = 0.14), respectively. Craving during the first 8 days was significantly reduced among highly dependent smokers on active treatment compared to placebo. Baseline mucosal lesions among abstinent subjects were reduced during the treatment period and at the non-treatment follow-up. Adverse events were mild and tolerable, the most common being irritation and soreness in the mouth and throat. Conclusion. The nicotine sublingual tablet increased the smoking cessation rate compared to placebo, reduced craving in highly dependent smokers and was well tolerated. [source] [FeFe]-Hydrogenase Models: Overpotential Control for Electrocatalytic H2 Production by Tuning of the Ligand ,-Acceptor AbilityEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 25 2010Fengwei Huo Abstract In the search for synthetic competitive catalysts that function with hydrogenase-like capability, a series of (Pyrrol-1-yl)phosphane-substituted diiron complexes [(,-pdt)Fe2(CO)5L] [pdt = propanedithiolate, L = Ph2PPyr (2), PPyr3 (4); Pyr = pyrrolyl] and [(,-pdt)Fe2(CO)4L2] [L = Ph2PPyr (3), PPyr3 (5)] were prepared as functional models for the active site of Fe-only hydrogenase. The structures of these complexes were fully characterized by spectroscopy and X-ray crystallography. In the IR spectra the CO bands for complexes 2,5 are shifted to higher energy relative to those of complexes with "traditional" phosphane ligands, such as PPh3, PMe3, and PTA (1,3,5-triaza-7-phosphaadamantane), indicating that (pyrrol-1-yl)phosphanes are poor ,-donors and better ,-acceptors. The electrochemical properties of complexes 2,5 were studied by cyclic voltammetry in CH3CN in the absence and presence of the the weak acid HOAc. The reduction potentials of these complexes show an anodic shift relative to other phosphane-substituted derivatives. All of the complexes can catalyze proton reduction from HOAc to H2 in CH3CN at their respective FeIFe0 level. Complex 4 is the most effective electrocatalyst, which catalytically generates H2 from HOAc at ,1.66 V vs. Fc+/Fc with only ca. 0.2 V overpotential in CH3CN. [source] Reversible, Fine Performance Tuning of an Organometallic Molecular Wire by Addition, Ligand Replacement and Removal of Dicobalt FragmentsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 23 2010Yuya Tanaka Abstract Communication between the two iron centres in (dithienylethyne)diyl complex 1 can be finely tuned by reversible addition to, ligand replacement at and removal from the C,C moiety in 1 of dicobalt fragments Co2(CO)n(PR3)6,n. Performance analysis reveals that disparate mechanisms are in operation for the two systems. In the case of the dicobalt adducts, indirect communication via the dicobalt steppingstone can be finely tuned by controlling the electronic structure of the dicobalt unit. [source] Cubane-Like Bismuth-Iron Cluster: Synthesis, X-ray Crystal Structure and Theoretical Characterization of the [Bi4Fe8(CO)28]4, AnionEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 20 2010Kirill Yu. Abstract The reaction of cyclo -Bi4[Si(SiMe3)3]4 (1) with Na2[Fe(CO)4] in the presence of nBu4NCl leads to the formation of the cage compound [nBu4N]4[Bi4Fe8(CO)28] (2). According to X-ray single-crystal structure analysis, the faces of the tetrahedral Bi4 core are capped by Fe(CO)3 moieties in a ,3 fashion to give a cubanoid Bi4Fe4 framework. The four Fe(CO)4 fragments are ,1 -coordinated to bismuth, each. With 12 skeletal electron pairs the [Bi4Fe8(CO)28]4, anion (2a) is a Bi4Fe4 cubane. The negative charge is localized within cluster 2a according to the NBO analysis of its derivatives. The strength of metal,ligand interactions Bi,,3 -Fe(CO)3 is responsible for the size of the cluster's cubic core. NICS computations at the cage centers of considered molecules show that 2a has paratropic character, whereas removal of four ,1 -Fe(CO)4 fragments from latter causes spherical aromaticity of the modified clusters [Bi4Fe4(CO)12]4, (2aa) and [Bi4Fe4(CO)12]2+ (2ab), mediated by a Bi4 cluster , orbital. [source] Reprogramming of a Malonic N-Heterocyclic Carbene: A Simple Backbone Modification with Dramatic Consequences on the Ligand's Donor PropertiesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 3 2010Vincent César Abstract Reaction of N,N, -dimesitylformamidine with dimethylmalonyl dichloride in dichloromethane in the presence of an excess of triethylamine gives the 2-chloro-4,5-dioxohexahydropyrimidine 1. The corresponding diamidocarbene 3 is generated in situ by further deprotonation with KHMDS at ,40 °C and identified by trapping with S8 to give the fully characterized (including X-ray structure) sulfur adduct 4. It also reacts with [RhCl(cod)]2 to yield the NHC complex [RhCl(3)(cod)] (5) (characterized also by X-ray structure). The donor properties of 3 were evaluated against the established IR [,(CO)] scale from [RhCl(3)(CO)2] (6). The average value of ,(CO) = 2045 cm,1 indicates that the diamidocarbene 3 is much less nucleophilic than structurally relevant six-membered NHCs including the anionic diaminocarbenes previously reported in our group. [source] Hydrido-Osmium(II), -Osmium(IV) and-Osmium(VI) Complexes with Functionalized Phosphanes as Ligands,EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 35 2009Birgit Richter Abstract Reaction of five-coordinate [OsHCl(CO)(PiPr3)2] (1) with the chelating phosphane iPr2PCH2CO2Me gave six-coordinate [OsHCl(CO)(PiPr3){,2(P,O)- iPr2PCH2C(=O)OMe}] (2), which upon treatment with CO and O2 afforded the 1:1 adducts [OsHCl(CO)(L)(PiPr3){,(P)- iPr2PCH2CO2Me}] (3, 4) by partial opening of the chelate ring. The vinyl complex [OsCl(CH=CHPh)(CO)(PiPr3){,2(P,O)- iPr2PCH2C(=O)OMe}] (5) was obtained from 2 and PhC,CH by insertion of the alkyne into the Os,H bond. Reaction of 2 with sodium acetate led to metathesis of the anionic ligands and formation of [OsH(,2 -O2CCH3)(CO)(PiPr3){,(P)- iPr2PCH2CO2Me}] (6). Osmium(VI) compounds [OsH6(PiPr2R)2] with R = CH2CH2OMe (12), CH2CO2Me (13) and CH2CO2Et (14), and [OsH6(PiPr3){,(P)- iPr2PCH2CH2NMe2}] (16) were prepared from osmium(IV) precursors and shown to rapidly react with O2 and primary alcohols. Exploratory studies revealed that the catalytic activity of the hexahydrido complexes in the hydrogen transfer reaction from 2-propanol to cyclohexanone and acetophenone depends on the type of the functionalized phosphane and is best for R = CH2CH2OMe. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Six-Membered N-Heterocyclic Carbenes with a 1,1,-Ferrocenediyl Backbone: Bulky Ligands with Strong Electron-Donor Capacity and Unusual Non-Innocent CharacterEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 31 2009Ulrich Siemeling Abstract The stable, crystalline N-heterocyclic diaminocarbene fc[N(CH2tBu)-C-N(CH2tBu)] (2d, fc = 1,1,-ferrocenediyl) was prepared by deprotonation of its formamidinium precursor fc[N(CH2tBu)-CH-N(CH2tBu)][BF4] (1d) and used for the preparation of the 16 valence electron complexes [Mo(2d)(CO)4], [RhCl(2d)(cod)] (cod = 1,5-cyclooctadiene) and [RhCl(2d)(CO)2]. 1d, 2d and [RhCl(2d)(cod)] were structurally characterised by single-crystal X-ray diffraction studies. The electrochemical properties of 2d, its 2-adamantyl analogue 2c, its complex [RhCl(2d)(CO)2] and of the precursors 1d and 1,1,-bis(neopentylamino)ferrocene were investigated by electrochemistry. The carbenes are easily oxidised to the corresponding radical cation, whose persistent nature is unprecedented in the chemistry of N-heterocyclic carbenes. The spin density is located at the Fe atom and the carbene C atom according to the results of EPR spectroscopic studies and DFT calculations.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Molybdenum Carbonyl Complexes Bearing PN Ligands Based on 2-Aminopyridine,EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 27 2009Christina Maria Standfest-Hauser Abstract Molybdenum complexes of the general formula Mo(PN)(CO)4 containing both achiral and chiral phosphorus-nitrogen donor bidentate ligands based on 2-aminopyridine were prepared and characterized by their NMR and IR spectra. The oxidative addition of allyl bromide to Mo(PN)(CO)4 was studied with PN = N -(diisopropylphosphanyl)-2-aminopyridine (PN- iPr). X-ray structures of representative compounds were determined. The mechanism of the oxidative addition of allyl bromide to Mo(PN- iPr)(CO)4 was analyzed by DFT/B3LYP calculations. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] | |||||||||||||||||||||||||||||||||||||||||||||||||