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Adapting the Stage of Change model to investigate adolescent behavior related to reducing second hand smoke exposure  [PDF]
Chris G. Richardson, Jennifer Schwartz, Laura L. Struik, Joan L. Bottorff
Open Journal of Preventive Medicine (OJPM) , 2013, DOI: 10.4236/ojpm.2013.32021
Abstract:

Aims: Second hand smoke (SHS) exposure is increasingly recognized as a major public health concern. Assessing adolescents’ motivational level to avoid SHS is vital to promote and reinforce reductions in SHS exposure. Methods: A brief measure based on the Stage of Change model was developed to characterize adolescents’ behavior related to reducing SHS exposure and used to identify potential determinants of SHS stage of change. The sample consisted of 1172 adolescents aged 13 to 15 years who participated in an internet-based cohort study of youth in British Columbia, Canada. Results: Sixty-six percent of the adolescents reported they had consistently made efforts to reduce exposure to SHS for more than 6 months, while 19% did not intend to reduce their exposure to SHS in the next 6 months. Adolescents’ SHS stage of change significantly differed by ethnicity, whether they had tried cigarettes, amount of tobacco smoked in their lifetime, parental and peer smoking statuses, past months’ exposure to SHS, frequent smoking in the home, and home smoking restrictions (all p < 0.05). Active smoking and more frequent exposure to SHS were associated with an increased probability of being in the pre-contemplation stage of change with regard to behavior related to reducing SHS exposure. Conclusion: This brief measure based

on the Stage of Change model can be used in future studies to characterize adolescents’ behavior around SHS. Adolescents who smoke or have parents and/or friends who smoke appear to be a population that could benefit from stage-matched interventions designed to raise awareness of the risks associated with SHS for smokers and non-smokers, and ultimately reduce SHS exposure.

The Influence of Web- Versus Paper-based Formats on the Assessment of Tobacco Dependence: Evaluating the Measurement Invariance of the Dimensions of Tobacco Dependence Scale
Chris G. Richardson, Joy L. Johnson, Pamela A. Ratner and Bruno D. Zumbo
Substance Abuse: Research and Treatment , 2012,
Abstract: The purpose of this study was to examine the influence of mode of administration (internet-based, web survey format versus pencil-and-paper format) on responses to the Dimensions of Tobacco Dependence Scale (DTDS). Responses from 1,484 adolescents that reported using tobacco (mean age 16 years) were examined; 354 (23.9%) participants completed a web-based version and 1,130 (76.1%) completed a paper-based version of the survey. Both surveys were completed in supervised classroom environments. Use of the web-based format was associated with significantly shorter completion times and a small but statistically significant increase in the number of missing responses. Tests of measurement invariance indicated that using a web-based mode of administration did not influence the psychometric functioning of the DTDS. There were no significant differences between the web- and paper-based groups’ ratings of the survey’s length, their question comprehension, and their response accuracy. Overall, the results of the study support the equivalence of scores obtained from web- and paper-based versions of the DTDS in secondary school settings.
The Influence of Web- Versus Paper-based Formats on the Assessment of Tobacco Dependence: Evaluating the Measurement Invariance of the Dimensions of Tobacco Dependence Scale
Chris G. Richardson,Joy L. Johnson,Pamela A. Ratner,Bruno D. Zumbo
Substance Abuse: Research and Treatment , 2009,
Abstract: The purpose of this study was to examine the influence of mode of administration (internet-based, web survey format versus pencil-and-paper format) on responses to the Dimensions of Tobacco Dependence Scale (DTDS). Responses from 1,484 adolescents that reported using tobacco (mean age 16 years) were examined; 354 (23.9%) participants completed a web-based version and 1,130 (76.1%) completed a paper-based version of the survey. Both surveys were completed in supervised classroom environments. Use of the web-based format was associated with significantly shorter completion times and a small but statistically significant increase in the number of missing responses. Tests of measurement invariance indicated that using a web-based mode of administration did not influence the psychometric functioning of the DTDS. There were no significant differences between the web- and paper-based groups’ ratings of the survey’s length, their question comprehension, and their response accuracy. Overall, the results of the study support the equivalence of scores obtained from web- and paper-based versions of the DTDS in secondary school settings.
The Hydroxylation of Vitamin D on C25 in Thyrotoxicosis The Role of the Activity of Microsomal Liver Enzymes  [PDF]
Chris G. Velentzas
International Journal of Clinical Medicine (IJCM) , 2012, DOI: 10.4236/ijcm.2012.34057
Abstract: Vitamin D3 after its entrance in the organism undergoes hydroxylation on C-25 carbon atom by the action of microsomal liver enzymes giving the metabolite 25 hydroxyvitamin D3 (25OHD3). The function of microsomal liver enzymes is influenced in some specified states by hormones or drugs. It has approved that thyroxin is a potent stimulator of these enzymes while allopurinol suppresses their function. The aim of this issue is to examine 25OHD3 plasma levels in thyrotoxic subjects and in those pretreated with allopurinol on the base of the afford mentioned data. In a first phase 25OHD3 plasma levels were estimated in thyrotoxic subjects against euthytoid healthy controls. In a second phase lmg vitamin D3 was injected intravenously (i.v.) in thyrotoxic subjects and in healthy euthyroid controls. 25OHD3 plasma levels were measured before and in post injection period in six hours intervals for 48 hours. In a third phase a couple of subjects one thyrotoxic and one euthyroid healthy control pretreated both with allopurinol injected lmg of vitamin D3 i.v. In all studied subjects 25OHD3 plasma levels were measured before and in post injection period in six hours intervals for 48 hours. The pre and post injection 25OHD3 plasma levels measured the size of activity of liver enzyme responsible for bioactivation of vitamin D3. In the first phase was indicated that 25OHD3 plasma levels were lower in thyrotoxic subjects comparing with that of euthyroid healthy controls (p < 0.001). In the second phase was found that the bioactivation of vitamin D3 in thyrotoxic subjects was 2,5 to 8 times faster comparing with euthyroid healthy controls. In the third phase was shown that allopurinol decreases the activity of liver enzymes function as regard the bioactivation of vitamin D3. The bioactivation of vitamin D3 is accelerated in thyrotoxicosis compared with that in euthyroid state. This phenomenon produces low 25OHD3 plasma levels in thyrotoxic subjects which initially may be normal or slightly increased depended from the vitamin D3 status in the thyrotoxic subjects. By continuous stimulatory action of increased thyroid hormones on liver enzymes the 25OHD3 plasma levels earlier or later decline in levels of hypo-or avitaminosis D3. The previously described biological events may explain the decreased intestinal calcium absorption of vitamin D3 and the osteomalacic
Geomagnetic activity during the rising phase of solar cycle 24
Richardson Ian G.
Journal of Space Weather and Space Climate , 2013, DOI: 10.1051/swsc/2013031
Abstract: As previous studies have shown, geomagnetic activity during the solar minimum following solar cycle 23 was at low levels unprecedented during the space era, and even since the beginning of the Kp index in 1932. Here, we summarize the characteristics of geomagnetic activity during the first 4 years of cycle 24 following smoothed sunspot minimum in December, 2008, and compare these with those of similar periods during earlier cycles going back to the start of Kp (cycles 17–23). The most outstanding feature is the continuing low levels of geomagnetic activity that are well below those observed during the rising phases of the other cycles studied. Even 4 years into cycle 24, geomagnetic storm rates are still only comparable to or below the rates observed during activity minima in previous cycles. We note that the storm rate during the rising phases of cycles 17–23 was correlated with the peak sunspot number (SSN) in the cycle. Extrapolating these results to the low storm rates in cycle 24 suggests values of the peak SSN in cycle 24 that are consistent with the NOAA Space Weather Prediction Center prediction of 90 ± 10, indicating that cycle 24 is likely to be the weakest cycle since at least 1932. No severe (Dst < 200 nT) storms have been observed during the first 4 years of cycle 24 compared with 4 in the comparable interval of cycle 23, and only 10 intense (Dst < 100 nT) storms, compared with 21 in cycle 23. These storms were all associated with the passage of Interplanetary Coronal Mass Ejections (ICMEs) and/or their associated sheaths. The lack of strong southward magnetic fields in ICMEs and their sheaths, their lower speeds close to the average solar wind speed, a ~20% reduction in the number of ICMEs passing the Earth, and weaker than normal fields in corotating high-speed streams, contribute to the low levels of geomagnetic storm activity in the rise phase of cycle 24. However, the observation of an ICME with strong southward fields at the STEREO A spacecraft on July 24, 2012, which would have been highly geoeffective had it encountered the Earth, demonstrates that strong geomagnetic storms may still occur during weak solar cycles.
Chiral Symmetry and the Nucleon Nucleon Interaction
Keith G. Richardson
Physics , 2000,
Abstract: Various aspects of the application of Effective Field Theory (EFT) to the Nucleon-Nucleon (NN) interaction are considered. We look for contributions beyond One Pion Exchange which are predicted by Chiral Symmetry. Using the formalism of the Wilson Renormalisation Group (RG) we review power counting in a simplified EFT containing only nucleons. For weak scattering at low energy, we find a natural expansion of the scattering matrix around the unique trivial fixed point of the RG. For strong scattering at low energy, the calculation can be organised in a useful and systematic way by expanding the potential around a non-trivial fixed point corresponding to a bound state of two nucleons at threshold. The resulting expansion of the inverse of the scattering matrix reproduces the effective range expansion order by order. The extension of this EFT to include pions in a manner consistent with chiral symmetry is discussed. By considering a modified effective range expansion, we find that the small momentum expansion in S-wave scattering converges slowly, if at all. The NN potential is written down to third order in small momenta. With a cut-off in coordinate space, we calculate phase shifts in peripheral partial waves for which the EFT predictions are parameter-free, and for which we may use the expansion around the trivial fixed point. We find several partial waves in which the effects of two-pion exchange can be isolated, but no strong evidence is found for the convergence of the small momentum expansion at this order.
Acceptability and implementation of PhysioDirect telephone advice and treatment services: a multi-perspective
Jennifer Pearson,Jane Richardson,Mike Calnan,Chris Salisbury
International Journal of Integrated Care , 2012,
Abstract:
Perinatal Outcome of Inadvertent Immunization with the Measles-Rubella Vaccine in Pregnant Mexican Women during the Campaign for the Eradication of Congenital Rubella in 2008  [PDF]
Reyna Jesus, Herbas Ilse, Gómez Misael, Vidal Patricia, Richardson Vesta, Cruz Edith, Cruz Edith
World Journal of Vaccines (WJV) , 2011, DOI: 10.4236/wjv.2011.11001
Abstract: Objective: To investigate maternal and neonatal complications resulting from inadvertent immunization against rubella-measles during the first trimester of pregnancy. Methods: A prospective and descriptive study was carried out, including a total of 1,924 pregnant women, 175 (9.1%) of which were classified as non responding to infection by the rubella virus. They underwent clinical and ultrasonographic follow-up to dismiss maternal or fetal complications and complications at the time of delivery. The infant was checked to determine demographic, anthropometric, serological and clinical features at the time of birth. Results: No women had complications during the pregnancy, including exanthematic symptoms. 174/175 newborns were studied; one pregnancy was interrupted based on non-medical arguments. The findings in terms of the analyzed patients suggest a benign evolution after inadvertently immunizing the pregnant women, which support studies with similar results. No complications during the course of the pregnancy or phenotypic alterations of the infant at the time of birth are suggested.
Compactifications of convergens spaces
D. C. Kent,G. D. Richardson
International Journal of Mathematics and Mathematical Sciences , 1979, DOI: 10.1155/s0161171279000302
Abstract: This paper summarizes most of the results to date on convergence space compactifications, and establishes necessary and sufficient conditions for the existence of largest and smallest compactifications subject to various conditions imposed upon the compactifications.
The star compactification
G. D. Richardson,D. C. Kent
International Journal of Mathematics and Mathematical Sciences , 1981, DOI: 10.1155/s016117128100032x
Abstract: The relationships between a convergence space and its star compactification is studied. Special attention is given to lifting properties of this compactification. In particular, it is shown that a natural extension of any continuous function to the respective compactification spaces is -continuous.
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