Effects of corporate social responsibility and governance on its credit ratings.

PubMed

Kim, Dong-young; Kim, JeongYeon

2014-01-01

This study reviews the impact of corporate social responsibility (CSR) and corporate governance on its credit rating. The result of regression analysis to credit ratings with relevant primary independent variables shows that both factors have significant effects on it. As we have predicted, the signs of both regression coefficients have a positive sign (+) proving that corporates with excellent CSR and governance index (CGI) scores have higher credit ratings and vice versa. The results show nonfinancial information also may have effects on corporate credit rating. The investment on personal data protection could be an example of CSR/CGI activities which have positive effects on corporate credit ratings.

A small unconditional non-financial incentive suggests an increase in survey response rates amongst older general practitioners (GPs): a randomised controlled trial study

PubMed Central

2013-01-01

Background Few studies have investigated the effect of small unconditional non-monetary incentives on survey response rates amongst GPs or medical practitioners. This study assessed the effectiveness of offering a small unconditional non-financial incentive to increase survey response rates amongst general practitioners within a randomised controlled trial (RCT). Methods An RCT was conducted within a general practice survey that investigated how to prolong working lives amongst ageing GPs in Australia. GPs (n = 125) were randomised to receive an attractive pen or no pen during their first invitation for participation in a survey. GPs could elect to complete the survey online or via mail. Two follow up reminders were sent without a pen to both groups. The main outcome measure was response rates. Results The response rate for GPs who received a pen was higher in the intervention group (61.9%) compared to the control group (46.8%). This study did not find a statistically significant effect of a small unconditional non-financial incentive (in the form of a pen) on survey response rates amongst GPs (Odds ratio, 95% confidence interval: 1.85 (0.91 to 3.77). No GPs completed the online version. Conclusion A small unconditional non-financial incentives, in the form of a pen, may improve response rates for GPs. PMID:23899116

A small unconditional non-financial incentive suggests an increase in survey response rates amongst older general practitioners (GPs): a randomised controlled trial study.

PubMed

Pit, Sabrina Winona; Hansen, Vibeke; Ewald, Dan

2013-07-30

Few studies have investigated the effect of small unconditional non-monetary incentives on survey response rates amongst GPs or medical practitioners. This study assessed the effectiveness of offering a small unconditional non-financial incentive to increase survey response rates amongst general practitioners within a randomised controlled trial (RCT). An RCT was conducted within a general practice survey that investigated how to prolong working lives amongst ageing GPs in Australia. GPs (n = 125) were randomised to receive an attractive pen or no pen during their first invitation for participation in a survey. GPs could elect to complete the survey online or via mail. Two follow up reminders were sent without a pen to both groups. The main outcome measure was response rates. The response rate for GPs who received a pen was higher in the intervention group (61.9%) compared to the control group (46.8%). This study did not find a statistically significant effect of a small unconditional non-financial incentive (in the form of a pen) on survey response rates amongst GPs (Odds ratio, 95% confidence interval: 1.85 (0.91 to 3.77). No GPs completed the online version. A small unconditional non-financial incentives, in the form of a pen, may improve response rates for GPs.

Effects of larkspur (Delphinium barbeyi) on heart rate and electrically evoked electromyographic response of the external anal sphincter in cattle.

PubMed

Green, Benedict T; Pfister, James A; Cook, Daniel; Welch, Kevin D; Stegelmeier, Bryan L; Lee, Stephen T; Gardner, Dale R; Knoppel, Edward L; Panter, Kip E

2009-04-01

OBJECTIVE-To determine whether larkspur-derived N-(methylsuccinimido) anthranoyllycoctonine (MSAL)-type alkaloids alter heart rate and electrically evoked electromyographic (eEMG) response of the external anal sphincter (EAS) in cattle and whether these effects can be reversed by acetylcholinesterase inhibitors. ANIMALS-12 beef heifers and 4 cows. PROCEDURES-3 or 4 heifers were used in 1 or 2 of 7 dose-response experiments; heart rate and EAS eEMG response were assessed before and 24 hours after oral treatment with larkspur (doses equivalent to 0.5 to 15 mg of MSAL-type alkaloids/kg). In 3 subsequent experiments, 3 heifers (1 of which was replaced with another heifer in the control experiment) each received 10 mg of MSAL-type alkaloids/kg and were injected IV with physostigmine (0.04 mg/kg), neostigmine (0.04 mg/kg), or saline (0.9% NaCl) solution 24 hours later, prior to assessment. Additionally, EAS eEMG response was measured in 4 cows before and after epidural administration of 2% lidocaine hydrochloride. RESULTS-Larkspur-treated heifers developed dose-related increases in heart rate and decreases in EAS eEMG response. Twenty-four hours after administration of MSAL-type alkaloids, neostigmine decreased heart rate but did not affect eEMG response, whereas physostigmine did not affect heart rate but caused a 2-fold increase in eEMG response. In cows, epidural anesthesia did not alter eEMG response, suggesting that transdermal stimulation of the EAS pudendal innervation did not occur. CONCLUSIONS AND CLINICAL RELEVANCE-In cattle, cardiac effects and muscle weakness or loss of EAS eEMG response induced by larkspur-derived MSAL-type alkaloids were reversed by neostigmine or physostigmine, respectively. Treatment with anticholinesterase inhibitors may alter the clinical effects of larkspur poisoning in cattle.

Prenotification but not envelope teaser increased response rates in a bulimia nervosa mental health literacy survey: A randomized controlled trial.

PubMed

McLean, Siân A; Paxton, Susan J; Massey, Robin; Mond, Jonathan M; Rodgers, Bryan; Hay, Phillipa J

2014-08-01

Understanding attitudes to mental health issues can inform public health interventions. However, low response rates may contribute to nonresponse bias. In a randomized controlled trial we examined the effect of sending a prenotification postcard before the questionnaire and the placement of a short message on the survey envelope (teaser) on response rates to a mailed questionnaire about bulimia nervosa "mental health literacy". Questionnaires were mailed to 3,010 adults (50.6% female and 49.4% male) aged 18-65 years. In a 2 (pre-notification-present; absent) by 2 (teaser-present; absent) design, questionnaire recipients were randomly allocated to the experimental strategies. Outcomes considered were response rate, response time, and cost. The overall response rate was 22.0%. Significant main effects showed higher response rates for the use of prenotification (present = 23.6%; absent = 20.3%), among female participants, and older participants. A significant interaction of teaser by gender indicated lower response rates for men who received the teaser but not for women. Older participants returned the questionnaire more promptly than younger participants. Females-but not males-who received the teaser were slower to return the questionnaire. Higher response rates for participants receiving the postcard compensated for increased costs, particularly for males and older participants. Response rates to a mental health postal survey can be increased through the use of prenotification. Copyright © 2014 Elsevier Inc. All rights reserved.

Are Sex Effects on Ethical Decision-Making Fake or Real? A Meta-Analysis on the Contaminating Role of Social Desirability Response Bias.

PubMed

Yang, Jianfeng; Ming, Xiaodong; Wang, Zhen; Adams, Susan M

2017-02-01

A meta-analysis of 143 studies was conducted to explore how the social desirability response bias may influence sex effects on ratings on measures of ethical decision-making. Women rated themselves as more ethical than did men; however, this sex effect on ethical decision-making was no longer significant when social desirability response bias was controlled. The indirect questioning approach was compared with the direct measurement approach for effectiveness in controlling social desirability response bias. The indirect questioning approach was found to be more effective.

Improving response rate and quality of survey data with a scratch lottery ticket incentive

PubMed Central

2012-01-01

Background The quality of data collected in survey research is usually indicated by the response rate; the representativeness of the sample, and; the rate of completed questions (item-response). In attempting to improve a generally declining response rate in surveys considerable efforts are being made through follow-up mailings and various types of incentives. This study examines effects of including a scratch lottery ticket in the invitation letter to a survey. Method Questionnaires concerning oral health were mailed to a random sample of 2,400 adults. A systematically selected half of the sample (1,200 adults) received a questionnaire including a scratch lottery ticket. One reminder without the incentive was sent. Results The incentive increased the response rate and improved representativeness by reaching more respondents with lower education. Furthermore, it reduced item nonresponse. The initial incentive had no effect on the propensity to respond after the reminder. Conclusion When attempting to improve survey data, three issues become important: response rate, representativeness, and item-response. This study shows that including a scratch lottery ticket in the invitation letter performs well on all the three. PMID:22515335

A randomised trial and economic evaluation of the effect of response mode on response rate, response bias, and item non-response in a survey of doctors.

PubMed

Scott, Anthony; Jeon, Sung-Hee; Joyce, Catherine M; Humphreys, John S; Kalb, Guyonne; Witt, Julia; Leahy, Anne

2011-09-05

Surveys of doctors are an important data collection method in health services research. Ways to improve response rates, minimise survey response bias and item non-response, within a given budget, have not previously been addressed in the same study. The aim of this paper is to compare the effects and costs of three different modes of survey administration in a national survey of doctors. A stratified random sample of 4.9% (2,702/54,160) of doctors undertaking clinical practice was drawn from a national directory of all doctors in Australia. Stratification was by four doctor types: general practitioners, specialists, specialists-in-training, and hospital non-specialists, and by six rural/remote categories. A three-arm parallel trial design with equal randomisation across arms was used. Doctors were randomly allocated to: online questionnaire (902); simultaneous mixed mode (a paper questionnaire and login details sent together) (900); or, sequential mixed mode (online followed by a paper questionnaire with the reminder) (900). Analysis was by intention to treat, as within each primary mode, doctors could choose either paper or online. Primary outcome measures were response rate, survey response bias, item non-response, and cost. The online mode had a response rate 12.95%, followed by the simultaneous mixed mode with 19.7%, and the sequential mixed mode with 20.7%. After adjusting for observed differences between the groups, the online mode had a 7 percentage point lower response rate compared to the simultaneous mixed mode, and a 7.7 percentage point lower response rate compared to sequential mixed mode. The difference in response rate between the sequential and simultaneous modes was not statistically significant. Both mixed modes showed evidence of response bias, whilst the characteristics of online respondents were similar to the population. However, the online mode had a higher rate of item non-response compared to both mixed modes. The total cost of the online survey was 38% lower than simultaneous mixed mode and 22% lower than sequential mixed mode. The cost of the sequential mixed mode was 14% lower than simultaneous mixed mode. Compared to the online mode, the sequential mixed mode was the most cost-effective, although exhibiting some evidence of response bias. Decisions on which survey mode to use depend on response rates, response bias, item non-response and costs. The sequential mixed mode appears to be the most cost-effective mode of survey administration for surveys of the population of doctors, if one is prepared to accept a degree of response bias. Online surveys are not yet suitable to be used exclusively for surveys of the doctor population.

A randomised trial and economic evaluation of the effect of response mode on response rate, response bias, and item non-response in a survey of doctors

PubMed Central

2011-01-01

Background Surveys of doctors are an important data collection method in health services research. Ways to improve response rates, minimise survey response bias and item non-response, within a given budget, have not previously been addressed in the same study. The aim of this paper is to compare the effects and costs of three different modes of survey administration in a national survey of doctors. Methods A stratified random sample of 4.9% (2,702/54,160) of doctors undertaking clinical practice was drawn from a national directory of all doctors in Australia. Stratification was by four doctor types: general practitioners, specialists, specialists-in-training, and hospital non-specialists, and by six rural/remote categories. A three-arm parallel trial design with equal randomisation across arms was used. Doctors were randomly allocated to: online questionnaire (902); simultaneous mixed mode (a paper questionnaire and login details sent together) (900); or, sequential mixed mode (online followed by a paper questionnaire with the reminder) (900). Analysis was by intention to treat, as within each primary mode, doctors could choose either paper or online. Primary outcome measures were response rate, survey response bias, item non-response, and cost. Results The online mode had a response rate 12.95%, followed by the simultaneous mixed mode with 19.7%, and the sequential mixed mode with 20.7%. After adjusting for observed differences between the groups, the online mode had a 7 percentage point lower response rate compared to the simultaneous mixed mode, and a 7.7 percentage point lower response rate compared to sequential mixed mode. The difference in response rate between the sequential and simultaneous modes was not statistically significant. Both mixed modes showed evidence of response bias, whilst the characteristics of online respondents were similar to the population. However, the online mode had a higher rate of item non-response compared to both mixed modes. The total cost of the online survey was 38% lower than simultaneous mixed mode and 22% lower than sequential mixed mode. The cost of the sequential mixed mode was 14% lower than simultaneous mixed mode. Compared to the online mode, the sequential mixed mode was the most cost-effective, although exhibiting some evidence of response bias. Conclusions Decisions on which survey mode to use depend on response rates, response bias, item non-response and costs. The sequential mixed mode appears to be the most cost-effective mode of survey administration for surveys of the population of doctors, if one is prepared to accept a degree of response bias. Online surveys are not yet suitable to be used exclusively for surveys of the doctor population. PMID:21888678

Regimes of heating and dynamical response in driven many-body localized systems

NASA Astrophysics Data System (ADS)

Gopalakrishnan, Sarang; Knap, Michael; Demler, Eugene

2016-09-01

We explore the response of many-body localized (MBL) systems to periodic driving of arbitrary amplitude, focusing on the rate at which they exchange energy with the drive. To this end, we introduce an infinite-temperature generalization of the effective "heating rate" in terms of the spread of a random walk in energy space. We compute this heating rate numerically and estimate it analytically in various regimes. When the drive amplitude is much smaller than the frequency, this effective heating rate is given by linear response theory with a coefficient that is proportional to the optical conductivity; in the opposite limit, the response is nonlinear and the heating rate is a nontrivial power law of time. We discuss the mechanisms underlying this crossover in the MBL phase. We comment on implications for the subdiffusive thermal phase near the MBL transition, and for response in imperfectly isolated MBL systems.

Respiratory sinus arrhythmia responses to induced emotional states: effects of RSA indices, emotion induction method, age, and sex.

PubMed

Overbeek, Thérèse J M; van Boxtel, Anton; Westerink, Joyce H D M

2012-09-01

The literature shows large inconsistencies in respiratory sinus arrhythmia (RSA) responses to induced emotional states. This may be caused by differences in emotion induction methods, RSA quantification, and non-emotional demands of the situation. In 83 healthy subjects, we studied RSA responses to pictures and film fragments eliciting six different discrete emotions relative to neutral baseline stimuli. RSA responses were quantified in the time and frequency domain and were additionally corrected for differences in mean heart rate and respiration rate, resulting in eight different RSA response measures. Subjective ratings of emotional stimuli and facial electromyographic responses indicated that pictures and film fragments elicited the intended emotions. Although RSA measures showed various emotional effects, responses were quite heterogeneous and frequently nonsignificant. They were substantially influenced by methodological factors, in particular time vs. frequency domain response measures, correction for changes in respiration rate, use of pictures vs. film fragments, and sex of participants. Copyright © 2012 Elsevier B.V. All rights reserved.

Monetary policy and the effects of oil price shocks on the Japanese economy

NASA Astrophysics Data System (ADS)

Lee, Byung Rhae

1998-12-01

The evidence of output decreases and price level increases following oil price shocks in the Japanese economy is presented in this paper. These negative effects of oil shocks are better explained by Hamilton's (1996) net oil price increase measure (NOPI) than by other oil measures. The fact that an oil shock has a statistically significant effect on the call money rate and real output and that the call money rate also has a statistically significant effect on real output appears to explain that the effects of oil price shocks on economic activity are partially attributed to contractionary monetary policy responses. The asymmetric effects of positive and negative oil shocks are also found in the Japanese economy and this asymmetry can also be partially explained by monetary policy responses. To assess the relative contribution of oil shocks and endogenous monetary policy responses to the economic downturns, I shut off the responses of the call money rate to oil shocks utilizing the impulse response results from the VAR model. Then, I re-run the VAR with the adjusted call money rate series. The empirical results show that around 30--40% of the negative effects of oil price shocks on the Japanese economy can be accounted for by oil shock induced monetary tightening.

Response Styles in Rating Scales: Simultaneous Modeling of Content-Related Effects and the Tendency to Middle or Extreme Categories

ERIC Educational Resources Information Center

Tutz, Gerhard; Berger, Moritz

2016-01-01

Heterogeneity in response styles can affect the conclusions drawn from rating scale data. In particular, biased estimates can be expected if one ignores a tendency to middle categories or to extreme categories. An adjacent categories model is proposed that simultaneously models the content-related effects and the heterogeneity in response styles.…

Resistance to change and frequency of response-dependent stimuli uncorrelated with reinforcement.

PubMed

Podlesnik, Christopher A; Jimenez-Gomez, Corina; Ward, Ryan D; Shahan, Timothy A

2009-09-01

Stimuli uncorrelated with reinforcement have been shown to enhance response rates and resistance to disruption; however, the effects of different rates of stimulus presentations have not been assessed. In two experiments, we assessed the effects of adding different rates of response-dependent brief stimuli uncorrelated with primary reinforcement on relative response rates and resistance to change. In both experiments, pigeons responded on variable-interval 60-s schedules of food reinforcement in two components of a multiple schedule, and brief response-dependent keylight-color changes were added to one or both components. Although relative response rates were not systematically affected in either experiment, relative resistance to presession feeding and extinction were. In Experiment 1, adding stimuli on a variable-interval schedule to one component of a multiple schedule either at a low rate (1 per min) for one group or at a high rate (4 per min) for another group similarly increased resistance to disruption in the components with added stimuli. When high and low rates of stimuli were presented across components (i.e., within subjects) in Experiment 2, however, relative resistance to disruption was greater in the component presenting stimuli at a lower rate. These results suggest that stimuli uncorrelated with food reinforcement do not strengthen responding in the same way as primary reinforcers.

The Effects of Parent-Focused Slow Relaxed Speech Intervention on Articulation Rate, Response Time Latency, and Fluency in Preschool Children Who Stutter

ERIC Educational Resources Information Center

Sawyer, Jean; Matteson, Colleen; Ou, Hua; Nagase, Takahisa

2017-01-01

Purpose: This study investigated the effects of an intervention to reduce caregivers' articulation rates with children who stutter on (a) disfluency, (b) caregiver and child's articulation rates, and (c) caregiver and child's response time latency (RTL). Method: Seventeen caregivers and their preschool children who stuttered participated in a…

Response rate, response time, and economic costs of survey research: A randomized trial of practicing pharmacists.

PubMed

Hardigan, Patrick C; Popovici, Ioana; Carvajal, Manuel J

2016-01-01

There is a gap between increasing demands from pharmacy journals, publishers, and reviewers for high survey response rates and the actual responses often obtained in the field by survey researchers. Presumably demands have been set high because response rates, times, and costs affect the validity and reliability of survey results. Explore the extent to which survey response rates, average response times, and economic costs are affected by conditions under which pharmacist workforce surveys are administered. A random sample of 7200 U.S. practicing pharmacists was selected. The sample was stratified by delivery method, questionnaire length, item placement, and gender of respondent for a total of 300 observations within each subgroup. A job satisfaction survey was administered during March-April 2012. Delivery method was the only classification showing significant differences in response rates and average response times. The postal mail procedure accounted for the highest response rates of completed surveys, but the email method exhibited the quickest turnaround. A hybrid approach, consisting of a combination of postal and electronic means, showed the least favorable results. Postal mail was 2.9 times more cost effective than the email approach and 4.6 times more cost effective than the hybrid approach. Researchers seeking to increase practicing pharmacists' survey participation and reduce response time and related costs can benefit from the analytical procedures tested here. Copyright © 2016 Elsevier Inc. All rights reserved.

HUMAN RESPONDING ON RANDOM-INTERVAL SCHEDULES OF RESPONSE-COST PUNISHMENT: THE ROLE OF REDUCED REINFORCEMENT DENSITY

PubMed Central

Pietras, Cynthia J; Brandt, Andrew E; Searcy, Gabriel D

2010-01-01

An experiment with adult humans investigated the effects of response-contingent money loss (response-cost punishment) on monetary-reinforced responding. A yoked-control procedure was used to separate the effects on responding of the response-cost contingency from the effects of reduced reinforcement density. Eight adults pressed buttons for money on a three-component multiple reinforcement schedule. During baseline, responding in all components produced money gains according to a random-interval 20-s schedule. During punishment conditions, responding during the punishment component conjointly produced money losses according to a random-interval schedule. The value of the response-cost schedule was manipulated across conditions to systematically evaluate the effects on responding of response-cost frequency. Participants were assigned to one of two yoked-control conditions. For participants in the Yoked Punishment group, during punishment conditions money losses were delivered in the yoked component response independently at the same intervals that money losses were produced in the punishment component. For participants in the Yoked Reinforcement group, responding in the yoked component produced the same net earnings as produced in the punishment component. In 6 of 8 participants, contingent response cost selectively decreased response rates in the punishment component and the magnitude of the decrease was directly related to the punishment schedule value. Under punishment conditions, for participants in the Yoked Punishment group response rates in the yoked component also decreased, but the decrease was less than that observed in the punishment component, whereas for participants in the Yoked Reinforcement group response rates in the yoked component remained similar to rates in the no-punishment component. These results provide further evidence that contingent response cost functions similarly to noxious punishers in that it appears to suppress responding apart from its effects on reinforcement density. PMID:20676265

"Bird in the hand" cash was more effective than prize draws in increasing physician questionnaire response.

PubMed

Drummond, Frances J; O'Leary, Eamonn; O'Neill, Ciaran; Burns, Richeal; Sharp, Linda

2014-02-01

To investigate the effects of two monetary incentives on response rates to postal questionnaires from primary care physicians (PCPs). The PCPs were randomized into three arms (n=550 per arm), namely (1) €5 sent with the questionnaire (cash); (2) entry into a draw on return of completed questionnaire (prize); or (3) no incentive. Effects of incentives on response rates and item nonresponse were examined, as was cost-effectiveness. Response rates were significantly higher in the cash (66.1%; 95% confidence interval [CI]: 61.9, 70.4%) and prize arms (44.8%; 95% CI: 40.1, 49.3%) compared with the no-incentive arm (39.9%; 95% CI: 35.4, 44.3%). Adjusted relative risk of response was 1.17 (95% CI: 1.02, 1.35) and 1.68 (95% CI: 1.48, 1.91) in the prize and cash arms, respectively, compared with the no-incentive group. Costs per completed questionnaire were €9.85, €11.15, and €6.31 for the cash, prize, and no-incentive arms, respectively. Compared with the no-incentive arm, costs per additional questionnaire returned in the cash and prize arms were €14.72 and €37.20, respectively. Both a modest cash incentive and entry into a prize draw were effective in increasing response rates. The cash incentive was most effective and the most cost-effective. Where it is important to maximize response, a modest cash incentive may be cost-effective. Copyright © 2014 Elsevier Inc. All rights reserved.

The Isolation of Motivational, Motoric, and Schedule Effects on Operant Performance: A Modeling Approach

PubMed Central

Brackney, Ryan J; Cheung, Timothy H. C; Neisewander, Janet L; Sanabria, Federico

2011-01-01

Dissociating motoric and motivational effects of pharmacological manipulations on operant behavior is a substantial challenge. To address this problem, we applied a response-bout analysis to data from rats trained to lever press for sucrose on variable-interval (VI) schedules of reinforcement. Motoric, motivational, and schedule factors (effort requirement, deprivation level, and schedule requirements, respectively) were manipulated. Bout analysis found that interresponse times (IRTs) were described by a mixture of two exponential distributions, one characterizing IRTs within response bouts, another characterizing intervals between bouts. Increasing effort requirement lengthened the shortest IRT (the refractory period between responses). Adding a ratio requirement increased the length and density of response bouts. Both manipulations also decreased the bout-initiation rate. In contrast, food deprivation only increased the bout-initiation rate. Changes in the distribution of IRTs over time showed that responses during extinction were also emitted in bouts, and that the decrease in response rate was primarily due to progressively longer intervals between bouts. Taken together, these results suggest that changes in the refractory period indicate motoric effects, whereas selective alterations in bout initiation rate indicate incentive-motivational effects. These findings support the use of response-bout analyses to identify the influence of pharmacological manipulations on processes underlying operant performance. PMID:21765544

The effects of rod and cone loss on the photic regulation of locomotor activity and heart rate.

PubMed

Thompson, Stewart; Lupi, Daniela; Hankins, Mark W; Peirson, Stuart N; Foster, Russell G

2008-08-01

Behavioral responses to light indirectly affect cardiovascular output, but in anesthetized rodents a direct effect of light on heart rate has also been described. Both the basis for this response and the contribution of rods, cones and melanopsin-based photosensitive retinal ganglion cells (pRGCs) remains unknown. To understand how light acutely regulates heart rate we studied responses to light in mice lacking all rod and cone photoreceptors (rd/rd cl ) along with wild-type controls. Our initial experiments delivered light to anesthetized mice at Zeitgeber time (ZT)16 (4 h after lights off, mid-activity phase) and produced an increase in heart rate in wild-type mice, but not in rd/rd cl animals. By contrast, parallel experiments in freely-moving mice demonstrated that light exposure at this time suppressed heart rate and activity in both genotypes. Because of the effects of anesthesia, all subsequent studies were conducted in freely-moving animals. The effects of light were also assessed at ZT6 (mid-rest phase). At this timepoint, wild-type mice showed an irradiance-dependent increase in heart rate and activity. By contrast, rd/rd cl mice failed to show any modulation of heart rate or activity, even at very high irradiances. Increases in heart rate preceded increases in locomotor activity and remained elevated when locomotor activity ceased, suggesting that these two responses are at least partially uncoupled. Collectively, our results show an acute and phase-dependent effect of light on cardiovascular output in mice. Surprisingly, this irradiance detection response is dependent upon rod and cone photoreceptors, with no apparent contribution from melanopsin pRGCs.

A metaanalysis of clinical trials comparing moclobemide with selective serotonin reuptake inhibitors for the treatment of major depressive disorder.

PubMed

Papakostas, George I; Fava, Maurizio

2006-10-01

To compare response rates among patients with major depressive disorder (MDD) treated with either moclobemide, an antidepressant thought to simultaneously enhance both noradrenergic and serotonergic neurotransmission, or selective serotonin reuptake inhibitors (SSRIs). Using a random-effects model, we combined 12 trials involving 1207 outpatients with MDD. Patients treated with moclobemide were as likely to experience clinical response as those treated with SSRIs (risk ratio 1.08; 95% confidence interval, 0.92 to 1.26; P = 0.314). Simply pooling response rates for the 2 agents resulted in a 62.1% response rate for moclobemide and a 57.5% response rate for the SSRIs. A metaregression did not reveal a statistically significant relation between the mean moclobemide dosage for each study and the risk ratio for response rates. Further, we found no difference between the 2 treatments in overall discontinuation rates, discontinuation rates due to adverse events, or discontinuation rates due to lack of efficacy. Also, rates of fatigue or somnolence and of insomnia were similar between the 2 treatment groups. However, SSRI treatment was associated with higher rates of nausea, headaches, and treatment-emergent anxiety than was treatment with moclobemide. These results suggest that moclobemide and the SSRIs do differ with respect to their side effect profiles but not in their overall efficacy in the treatment of MDD.

Differential Effects of Incentives on Response Error, Response Rate, and Reliability of a Mailed Questionnaire.

ERIC Educational Resources Information Center

Brown, Darine F.; Hartman, Bruce

1980-01-01

Investigated issues associated with stimulating increased return rates to a mail questionnaire among school counselors. Results show that as the number of incentives received increased, the return rates increased in a linear fashion. The incentives did not introduce response error or affect the reliability of the Counselor Function Inventory.…

Influences of Response Rate and Distribution on the Calculation of Interobserver Reliability Scores

ERIC Educational Resources Information Center

Rolider, Natalie U.; Iwata, Brian A.; Bullock, Christopher E.

2012-01-01

We examined the effects of several variations in response rate on the calculation of total, interval, exact-agreement, and proportional reliability indices. Trained observers recorded computer-generated data that appeared on a computer screen. In Study 1, target responses occurred at low, moderate, and high rates during separate sessions so that…

Tactics to Increase Course Evaluation Response Rates: A Comparison of Effectiveness

ERIC Educational Resources Information Center

Jacek, Laura

2015-01-01

When an institution decides to move to online teaching evaluations, they often face concerns that their response rates will fall with the change. This fear need never come to pass, however. There are many interventions that can raise response rates. Good communication strategies, improved student and faculty engagement, and grade hold are just a…

Improving Survey Response Rates of School Counselors: Comparing the Use of Incentives

ERIC Educational Resources Information Center

Bauman, Sheri

2007-01-01

This article examines the effectiveness of incentives in improving survey response rates of school counselors and compares the findings with those of previously researched populations. A $1 cash incentive increased response rates for a one-wave mailing of a questionnaire, while a raffle opportunity did not. The number and length of optional…

33 CFR 154.1130 - Requirements for prepositioned response equipment.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Additional Response Plan Requirements for a Trans-Alaska Pipeline Authorization Act (TAPAA) Facility...: (a) On-water recovery equipment with a minimum effective daily recovery rate of 30,000 barrels... of a discharge. (c) On-water recovery equipment with a minimum effective daily recovery rate of 40...

33 CFR 154.1130 - Requirements for prepositioned response equipment.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Additional Response Plan Requirements for a Trans-Alaska Pipeline Authorization Act (TAPAA) Facility...: (a) On-water recovery equipment with a minimum effective daily recovery rate of 30,000 barrels... of a discharge. (c) On-water recovery equipment with a minimum effective daily recovery rate of 40...

33 CFR 154.1130 - Requirements for prepositioned response equipment.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Additional Response Plan Requirements for a Trans-Alaska Pipeline Authorization Act (TAPAA) Facility...: (a) On-water recovery equipment with a minimum effective daily recovery rate of 30,000 barrels... of a discharge. (c) On-water recovery equipment with a minimum effective daily recovery rate of 40...

33 CFR 154.1130 - Requirements for prepositioned response equipment.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Additional Response Plan Requirements for a Trans-Alaska Pipeline Authorization Act (TAPAA) Facility...: (a) On-water recovery equipment with a minimum effective daily recovery rate of 30,000 barrels... of a discharge. (c) On-water recovery equipment with a minimum effective daily recovery rate of 40...

The effect of single engine fixed wing air transport on rate-responsive pacemakers.

PubMed

De Rotte, A A; Van Der Kemp, P

1999-09-01

Insufficient information exists about the safety of patients with accelerometer-based rate-responsive pacemakers in air transport by general aviation aircraft. The response in pacing rate of two types of accelerometer-based rate-responsive pacemakers with data logging capabilities was studied during test flights with single engine fixed wing aircraft. Results were compared with the rate-response of these pacemakers during transportation by car and were also interpreted in respect to physiological heart rate response of aircrew during flights in single engine fixed wing aircraft. In addition, a continuous accelerometer readout was recorded during a turbulent phase of flight. This recording was used for a pacemaker-simulator experiment with maximal sensitive motion-sensor settings. Only a minor increase in pacing rate due to aircraft motion could be demonstrated during all phases of flight at all altitudes with the pacemakers programmed in the normal mode. This increase was of the same magnitude as induced during transport by car and would be of negligible influence on the performance of the individual pacemaker patient equipped with such a pacemaker. Moreover, simultaneous Holter monitoring of the pilots during these flights showed a similar rate-response in natural heart rate compared with the increase in pacing rate induced by aircraft motion in accelerometer-based rate-responsive pacemakers. No sensor-mediated pacemaker tachycardia was seen during any of these recordings. However, a 15% increase in pacing rate was induced by severe air turbulence. Programming the maximal sensitivity of the motion sensor into the pacemaker could, on the other hand, induce a significant increase in pacing rate as was demonstrated by the simulation experiments. These results seem to rule out potentially dangerous or adverse effects from motional or vibrational influences during transport in single engine fixed wing aircraft on accelerometer-based rate-responsive pacemakers with normal activity sensor settings.

Is it too early to move to full electronic PROM data collection?: A randomized controlled trial comparing PROM's after hallux valgus captured by e-mail, traditional mail and telephone.

PubMed

Palmen, Leonieke N; Schrier, Joost C M; Scholten, Ruben; Jansen, Justus H W; Koëter, Sander

2016-03-01

Patient reported outcome measures (PROM's) after hallux valgus surgery are used to rate the effectiveness as perceived by the patient. The interpretability of these PROM's is highly dependent on participation rate. Data capture method may be an important factor contributing to the response rate. We investigated the effect on response rate of traditional paper mail, telephone and e-mail PROM's after hallux valgus surgery. All consecutive patients operated between January and September 2013, were identified. Included patients were randomized by envelope in three groups: traditional pen and paper mail, e-mail and telephone. They were asked to fill in a FFI and EQ-5D. Two weeks later non-responders were sent a reminder. Of the 73 included patients, 25 were approached by mail, 24 by e-mail and 24 patients by telephone. The response rate on traditional mail was highest (88%), while response on e-mail was lowest (33%). Response rate on telephone was also high (79%). Response rate on traditional mail and telephone was significantly higher (p<0.001) than response on e-mail. Though electronic data collection has enormous potential, this study shows that e-mail yields unacceptable low response rates. It is too early to replace traditional pen-and-paper PROM's by electronic questionnaires. Copyright © 2015 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

National survey of physicians to determine the effect of unconditional incentives on response rates of physician postal surveys

PubMed Central

Abdulaziz, Kasim; Brehaut, Jamie; Taljaard, Monica; Émond, Marcel; Sirois, Marie-Josée; Lee, Jacques S; Wilding, Laura; Perry, Jeffrey J

2015-01-01

Objectives Physicians are a commonly targeted group in health research surveys, but their response rates are often relatively low. The goal of this paper was to evaluate the effect of unconditional incentives in the form of a coffee card on physician postal survey response rates. Design Following 13 key informant interviews and eight cognitive interviews a survey questionnaire was developed. Participants A random sample of 534 physicians, stratified by physician group (geriatricians, family physicians, emergency physicians) was selected from a national medical directory. Setting Using computer generated random numbers; half of the physicians in each stratum were allocated to receive a coffee card to a popular national coffee chain together with the first survey mailout. Interventions The intervention was a $10 Tim Hortons gift card given to half of the physicians who were randomly allocated to receive the incentive. Results 265 (57.0%) physicians completed the survey. The response rate was significantly higher in the group allocated to receive the incentive (62.7% vs 51.3% in the control group; p=0.01). Conclusions Our results indicate that an unconditional incentive in the form of a coffee gift card can substantially improve physician response rates. Future research can look at the effect of varying amounts of cash on the gift cards on response rates. PMID:25694460

Comparison of the discriminative stimulus and response rate effects of Δ9-tetrahydrocannabinol and synthetic cannabinoids in female and male rats.

PubMed

Wiley, Jenny L; Lefever, Timothy W; Marusich, Julie A; Craft, Rebecca M

2017-03-01

Women report greater sensitivity to the subjective effects of Δ 9 -tetrahydrocannabinol (THC). Similarly, female rodents tend to be more sensitive to some pharmacological effects of THC and synthetic cannabinoids. This study examined sex differences in discriminative stimulus and response rate effects of THC and synthetic cannabinoids in rats. A cumulative dosing THC discrimination procedure was utilized to evaluate sex differences in the discriminative stimulus effects of THC and three synthetic cannabinoids: CP47,497, WIN55,212-2, and JWH-018. Sex differences in the effects of these four compounds and a degradant of A-834735 on response rates also were assessed in a food-reinforced discrete dosing procedure. Females required a lower training dose than males for acquisition of the discrimination. Further, THC was more potent at producing rimonabant-reversible discriminative stimulus and response rate effects in females. While synthetic cannabinoids were more potent in producing THC-like effects than was THC in female rats, greater discrepancies were observed in male rats. Similar sensitivity to the response rate-decreasing effects induced by most, but not all (A-834735 degradant), synthetic cannabinoids was seen in both sexes. This study represents one of the first direct comparisons of sex differences in THC discrimination. Females were more sensitive to THC's effects, which may be related, in part, to sex differences in THC metabolism. Synthetic cannabinoids were more potent than THC in both sexes, but were considerably more so in male than in female rats. Future research should emphasize further characterization of sex differences in cannabinoid pharmacology. Copyright © 2017 Elsevier B.V. All rights reserved.

Comparison of the discriminative stimulus and response rate effects of Δ9-tetrahydrocannabinol and synthetic cannabinoids in female and male rats*

PubMed Central

Wiley, Jenny L.; Lefever, Timothy W.; Marusich, Julie A.; Craft, Rebecca M.

2017-01-01

Background Women report greater sensitivity to the subjective effects of Δ9-tetrahydrocannabinol (THC). Similarly, female rodents tend to be more sensitive to some pharmacological effects of THC and synthetic cannabinoids. This study examined sex differences in discriminative stimulus and response rate effects of THC and synthetic cannabinoids in rats. Methods A cumulative dosing THC discrimination procedure was utilized to evaluate sex differences in the discriminative stimulus effects of THC and three synthetic cannabinoids: CP47,497, WIN55,212-2, and JWH-018. Sex differences in the effects of these four compounds and a degradant of A-834735 on response rates also were assessed in a food-reinforced discrete dosing procedure. Results Females required a lower training dose than males for acquisition of the discrimination. Further, THC was more potent at producing rimonabant-reversible discriminative stimulus and response rate effects in females. While synthetic cannabinoids were more potent in producing THC-like effects than was THC in female rats, greater discrepancies were observed in male rats. Similar sensitivity to the response rate-decreasing effects induced by most, but not all (A-834735 degradant), synthetic cannabinoids was seen in both sexes. Conclusions This study represents one of the first direct comparisons of sex differences in THC discrimination. Females were more sensitive to THC’s effects, which may be related, in part, to sex differences in THC metabolism. Synthetic cannabinoids were more potent than THC in both sexes, but were considerably more so in male than in female rats. Future research should emphasize further characterization of sex differences in cannabinoid pharmacology. PMID:28130989

High Familial Correlation in Methylphenidate Response and Side Effect Profile.

PubMed

Gazer-Snitovsky, Michal; Brand-Gothelf, Ayelet; Dubnov-Raz, Gal; Weizman, Abraham; Gothelf, Doron

2015-04-21

To examine whether a familial tendency exists in clinical response to methylphenidate. Nineteen pairs of siblings or parent-child stimulant-naive individuals with ADHD were prescribed methylphenidate-immediate release, and were comprehensively evaluated at baseline, Week 2, and Week 4, using the ADHD Rating Scale IV, Clinical Global Impression Scale, and the Barkley Side Effects Rating Scale. We found significant intraclass correlations in family member response to methylphenidate-immediate release and side effect profile, including emotional symptoms and loss of appetite and weight. Family history of response to methylphenidate should be taken into account when treating ADHD. © 2015 SAGE Publications.

Evaluation of the effect of reactant gases mass flow rates on power density in a polymer electrolyte membrane fuel cell

NASA Astrophysics Data System (ADS)

Kahveci, E. E.; Taymaz, I.

2018-03-01

In this study it was experimentally investigated the effect of mass flow rates of reactant gases which is one of the most important operational parameters of polymer electrolyte membrane (PEM) fuel cell on power density. The channel type is serpentine and single PEM fuel cell has an active area of 25 cm2. Design-Expert 8.0 (trial version) was used with four variables to investigate the effect of variables on the response using. Cell temperature, hydrogen mass flow rate, oxygen mass flow rate and humidification temperature were selected as independent variables. In addition, the power density was used as response to determine the combined effects of these variables. It was kept constant cell and humidification temperatures while changing mass flow rates of reactant gases. From the results an increase occurred in power density with increasing the hydrogen flow rates. But oxygen flow rate does not have a significant effect on power density within determined mass flow rates.

The impact of vaccine failure rate on epidemic dynamics in responsive networks.

PubMed

Liang, Yu-Hao; Juang, Jonq

2015-04-01

An SIS model based on the microscopic Markov-chain approximation is considered in this paper. It is assumed that the individual vaccination behavior depends on the contact awareness, local and global information of an epidemic. To better simulate the real situation, the vaccine failure rate is also taken into consideration. Our main conclusions are given in the following. First, we show that if the vaccine failure rate α is zero, then the epidemic eventually dies out regardless of what the network structure is or how large the effective spreading rate and the immunization response rates of an epidemic are. Second, we show that for any positive α, there exists a positive epidemic threshold depending on an adjusted network structure, which is only determined by the structure of the original network, the positive vaccine failure rate and the immunization response rate for contact awareness. Moreover, the epidemic threshold increases with respect to the strength of the immunization response rate for contact awareness. Finally, if the vaccine failure rate and the immunization response rate for contact awareness are positive, then there exists a critical vaccine failure rate αc > 0 so that the disease free equilibrium (DFE) is stable (resp., unstable) if α < αc (resp., α > αc). Numerical simulations to see the effectiveness of our theoretical results are also provided.

Synthesized speech rate and pitch effects on intelligibility of warning messages for pilots

NASA Technical Reports Server (NTRS)

Simpson, C. A.; Marchionda-Frost, K.

1984-01-01

In civilian and military operations, a future threat-warning system with a voice display could warn pilots of other traffic, obstacles in the flight path, and/or terrain during low-altitude helicopter flights. The present study was conducted to learn whether speech rate and voice pitch of phoneme-synthesized speech affects pilot accuracy and response time to typical threat-warning messages. Helicopter pilots engaged in an attention-demanding flying task and listened for voice threat warnings presented in a background of simulated helicopter cockpit noise. Performance was measured by flying-task performance, threat-warning intelligibility, and response time. Pilot ratings were elicited for the different voice pitches and speech rates. Significant effects were obtained only for response time and for pilot ratings, both as a function of speech rate. For the few cases when pilots forgot to respond to a voice message, they remembered 90 percent of the messages accurately when queried for their response 8 to 10 sec later.

Effect of paper quality on the response rate to a postal survey: A randomised controlled trial. [ISRCTN32032031

PubMed Central

Clark, T Justin; Khan, Khalid S; Gupta, Janesh K

2001-01-01

Background Response rates to surveys are declining and this threatens the validity and generalisability of their findings. We wanted to determine whether paper quality influences the response rate to postal surveys Methods A postal questionnaire was sent to all members of the British Society of Gynaecological Endoscopy (BSGE). Recipients were randomised to receiving the questionnaire printed on standard quality paper or high quality paper. Results The response rate for the recipients of high quality paper was 43/195 (22%) and 57/194 (29%) for standard quality paper (relative rate of response 0.75, 95% CI 0.33–1.05, p = 0.1 Conclusion The use of high quality paper did not increase response rates to a questionnaire survey of gynaecologists affiliated to an endoscopic society. PMID:11782286

Surveying Alumni by Mail: Effect of Booklet/Folder Questionnaire Format and Style of Type on Response Rate.

ERIC Educational Resources Information Center

Boser, Judith A.

1990-01-01

Two investigations, each involving a survey of university alumni, found that questionnaire type font (conventional typewriter type and professional-appearing type) and construction (single pages, stapled, and booklet) did not have a significant effect on response rates. Other considerations that may influence questionnaire design decisions are…

The Effects of Elevated Temperatures on the Response of Resins Under Dynamic and Static Loadings

NASA Technical Reports Server (NTRS)

Gilat, Amos

2005-01-01

The overall objective of the research is to experimentally study the combined effects of temperature and strain rate on the response of two resins that are commonly used for the matrix material in composites. The resins are loaded at various temperatures in shear and in tension over a wide range of strain rates. These two types of loadings provide an opportunity to examine also the effect that temperature might have on the effects of the hydrostatic stress component on the material response. The experimental data provide the information needed for NASA scientists for the development of a nonlinear, strain rate, and temperature dependent deformation and strength models for composites that can subsequently be used in design. This year effort was directed into the development and testing of the epoxy resin at elevated temperatures. Two types of epoxy resins were tested in shear at high strain rates of about 10(exp-4)/s and elevated temperatures of 50 and 8OC. The results show that the temperature significantly affects the response of epoxy.

Differential Classical Conditioning of the Nocebo Effect: Increasing Heat-Pain Perception without Verbal Suggestions

PubMed Central

Bräscher, Anne-Kathrin; Kleinböhl, Dieter; Hölzl, Rupert; Becker, Susanne

2017-01-01

Background: Nocebo effects, including nocebo hyperalgesia, are a common phenomenon in clinical routine with manifold negative consequences. Both explicit expectations and learning by conditioning are known to induce nocebo effects, but the specific role of conditioning remains unclear, because conditioning is rarely implemented independent of verbal suggestions. Further, although pain is a multidimensional phenomenon, nocebo effects are usually assessed in subjective ratings only, neglecting, e.g., behavioral aspects. The aim of this study was to test whether nocebo hyperalgesia can be learned by conditioning without explicit expectations, to assess nocebo effects in different response channels, and to exploratively assess, whether contingency awareness is a necessary condition for conditioned nocebo hyperalgesia. Methods: Twenty-one healthy volunteers were classically conditioned using painful and non-painful heat stimuli that followed two different cues. The conditioned nocebo effect was assessed by subjective ratings of perceived stimulation intensity on a visual analog scale and a behavioral discrimination task, assessing sensitization and habituation in response to the same stimulation following the two cues. Results: Results show a conditioned nocebo effect indicated by the subjective intensity ratings. Conditioned effects were also seen in the behavioral responses, but paradoxically, behavioral responses indicated decreased perception after conditioning, but only for subjects successfully conditioned as indicated by the subjective ratings. Explorative analyses suggested that awareness of the contingencies and the different cues was not necessary for successful conditioning. Conclusion: Nocebo effects can be learned without inducing additional explicit expectations. The dissociation between the two response channels, possibly representing the conditioned and a compensatory response, highlights the importance of considering different outcomes in nocebo responses to fully understand underlying mechanisms. The present results challenge the role of explicit expectations in conditioned nocebo effects and are relevant with implications in clinical contexts, e.g., when transient adverse effects become conditioned. PMID:29321752

Increasing the response rate of text messaging data collection: a delayed randomized controlled trial

PubMed Central

Li, Ye; Wang, Wei; Wu, Qiong; van Velthoven, Michelle Helena; Chen, Li; Du, Xiaozhen; Zhang, Yanfeng; Rudan, Igor; Car, Josip

2015-01-01

Objective To test the effectiveness of multiple interventions on increasing the response rate of text messaging for longitudinal data collection. Methods Our cohort included 283 caregivers of children aged 6–12 months who were participating in an anemia program in rural China. Using text messages to collect data on anemia medication adherence, we conducted a delayed randomized controlled trial to test multiple interventions (an additional four reminders; a ¥5.0 (US$0.79) credit reward for replying; and a feedback text message). After a 6-week pilot study with week 7 as the baseline measurement, we randomly allocated all participants into two groups: group 1 (n = 142) and group 2 (n = 141). During weeks 8–11, we introduced the interventions to group 1, and in weeks 12–15 the intervention was introduced to both groups. We compared the response rates between groups and explored factors affecting the response rate. Results During weeks 8–11, the response rates in group 1 increased and were significantly higher than in group 2 (p<0.05). During weeks 12–15, the response rate increased significantly in group 2 (p>0.05) and slightly decreased in group 1. Younger participants or participants who had children with lower hemoglobin concentration were more likely to reply (p = 0.02). Sending four reminders on the second day contributed to only 286 (11.7%) extra text messages. Discussion Our study showed that multiple interventions were effective in increasing response rate of text messaging data collection in rural China. Conclusions Larger multi-site studies are needed to find the most effective way of using these interventions to allow usage of text messaging data collection for health research. PMID:25332355

Statistical Application and Cost Saving in a Dental Survey.

PubMed

Chyou, Po-Huang; Schroeder, Dixie; Schwei, Kelsey; Acharya, Amit

2017-06-01

To effectively achieve a robust survey response rate in a timely manner, an alternative approach to survey distribution, informed by statistical modeling, was applied to efficiently and cost-effectively achieve the targeted rate of return. A prospective environmental scan surveying adoption of health information technology utilization within their practices was undertaken in a national pool of dental professionals (N=8000) using an alternative method of sampling. The piloted approach to rate of cohort sampling targeted a response rate of 400 completed surveys from among randomly targeted eligible providers who were contacted using replicated subsampling leveraging mailed surveys. Two replicated subsample mailings (n=1000 surveys/mailings) were undertaken to project the true response rate and estimate the total number of surveys required to achieve the final target. Cost effectiveness and non-response bias analyses were performed. The final mailing required approximately 24% fewer mailings compared to targeting of the entire cohort, with a final survey capture exceeding the expected target. An estimated $5000 in cost savings was projected by applying the alternative approach. Non-response analyses found no evidence of bias relative to demographics, practice demographics, or topically-related survey questions. The outcome of this pilot study suggests that this approach to survey studies will accomplish targeted enrollment in a cost effective manner. Future studies are needed to validate this approach in the context of other survey studies. © 2017 Marshfield Clinic.

Statistical Application and Cost Saving in a Dental Survey

PubMed Central

Chyou, Po-Huang; Schroeder, Dixie; Schwei, Kelsey; Acharya, Amit

2017-01-01

Objective To effectively achieve a robust survey response rate in a timely manner, an alternative approach to survey distribution, informed by statistical modeling, was applied to efficiently and cost-effectively achieve the targeted rate of return. Design A prospective environmental scan surveying adoption of health information technology utilization within their practices was undertaken in a national pool of dental professionals (N=8000) using an alternative method of sampling. The piloted approach to rate of cohort sampling targeted a response rate of 400 completed surveys from among randomly targeted eligible providers who were contacted using replicated subsampling leveraging mailed surveys. Methods Two replicated subsample mailings (n=1000 surveys/mailings) were undertaken to project the true response rate and estimate the total number of surveys required to achieve the final target. Cost effectiveness and non-response bias analyses were performed. Results The final mailing required approximately 24% fewer mailings compared to targeting of the entire cohort, with a final survey capture exceeding the expected target. An estimated $5000 in cost savings was projected by applying the alternative approach. Non-response analyses found no evidence of bias relative to demographics, practice demographics, or topically-related survey questions. Conclusion The outcome of this pilot study suggests that this approach to survey studies will accomplish targeted enrollment in a cost effective manner. Future studies are needed to validate this approach in the context of other survey studies. PMID:28373286

The role of fear and disgust in predicting the effectiveness of television advertisements that graphically depict the health harms of smoking.

PubMed

Jónsdóttir, Harpa Lind; Holm, Jeffrey E; Poltavski, Dmitri; Vogeltanz-Holm, Nancy

2014-12-11

Antismoking television advertisements that depict the graphic health harms of smoking are increasingly considered best practices, as exemplified by the Centers for Disease Control and Prevention's current national campaign. Evaluation of responses to these widely used advertisements is important to determine advertisements that are most effective and their mechanisms of action. Our study tested the hypothesis that advertisements rated highest in fear- and disgust-eliciting imagery would be rated as the most effective. Our laboratory study included 144 women and men aged 18 to 33; 84% were current nonsmokers. All participants viewed 6 antismoking television advertisements that depicted the health harms of smoking; they rated their responses of fear and disgust and the effectiveness of the advertisements. We used multilevel modeling to test the effects of the following in predicting effectiveness: fear, disgust, the fear-disgust interaction, the advertisement, and the participant's sex and smoking status. Follow-up analyses examined differences in ratings of fear, disgust, and effectiveness. Advertisement, fear, disgust, and the fear-disgust interaction were each significant predictors of effectiveness. Smoking status and sex were not significant predictors. The 3 advertisements that elicited the highest ratings of fear and disgust were rated the most effective. Our findings support the hypothesis that antismoking advertisements of health harms that elicit the greatest responses of fear or disgust are the most effective. When advertisements elicit high ratings of both fear and disgust, advertisements with graphic imagery are effective, whereas advertisements without graphic imagery are not.

The Role of Fear and Disgust in Predicting the Effectiveness of Television Advertisements That Graphically Depict the Health Harms of Smoking

PubMed Central

Jónsdóttir, Harpa Lind; Holm, Jeffrey E.; Poltavski, Dmitri

2014-01-01

Introduction Antismoking television advertisements that depict the graphic health harms of smoking are increasingly considered best practices, as exemplified by the Centers for Disease Control and Prevention’s current national campaign. Evaluation of responses to these widely used advertisements is important to determine advertisements that are most effective and their mechanisms of action. Our study tested the hypothesis that advertisements rated highest in fear- and disgust-eliciting imagery would be rated as the most effective. Methods Our laboratory study included 144 women and men aged 18 to 33; 84% were current nonsmokers. All participants viewed 6 antismoking television advertisements that depicted the health harms of smoking; they rated their responses of fear and disgust and the effectiveness of the advertisements. We used multilevel modeling to test the effects of the following in predicting effectiveness: fear, disgust, the fear–disgust interaction, the advertisement, and the participant’s sex and smoking status. Follow-up analyses examined differences in ratings of fear, disgust, and effectiveness. Results Advertisement, fear, disgust, and the fear–disgust interaction were each significant predictors of effectiveness. Smoking status and sex were not significant predictors. The 3 advertisements that elicited the highest ratings of fear and disgust were rated the most effective. Conclusion Our findings support the hypothesis that antismoking advertisements of health harms that elicit the greatest responses of fear or disgust are the most effective. When advertisements elicit high ratings of both fear and disgust, advertisements with graphic imagery are effective, whereas advertisements without graphic imagery are not. PMID:25496558

National survey of physicians to determine the effect of unconditional incentives on response rates of physician postal surveys.

PubMed

Abdulaziz, Kasim; Brehaut, Jamie; Taljaard, Monica; Émond, Marcel; Sirois, Marie-Josée; Lee, Jacques S; Wilding, Laura; Perry, Jeffrey J

2015-02-18

Physicians are a commonly targeted group in health research surveys, but their response rates are often relatively low. The goal of this paper was to evaluate the effect of unconditional incentives in the form of a coffee card on physician postal survey response rates. Following 13 key informant interviews and eight cognitive interviews a survey questionnaire was developed. A random sample of 534 physicians, stratified by physician group (geriatricians, family physicians, emergency physicians) was selected from a national medical directory. Using computer generated random numbers; half of the physicians in each stratum were allocated to receive a coffee card to a popular national coffee chain together with the first survey mailout. The intervention was a $10 Tim Hortons gift card given to half of the physicians who were randomly allocated to receive the incentive. 265 (57.0%) physicians completed the survey. The response rate was significantly higher in the group allocated to receive the incentive (62.7% vs 51.3% in the control group; p=0.01). Our results indicate that an unconditional incentive in the form of a coffee gift card can substantially improve physician response rates. Future research can look at the effect of varying amounts of cash on the gift cards on response rates. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

The effect of age on outcomes after isolated limb perfusion for advanced extremity malignancies.

PubMed

Smith, H G; Wilkinson, M J; Smith, M J F; Strauss, D C; Hayes, A J

2018-06-22

Isolated limb perfusion (ILP) is a well-established treatment for patients with advanced extremity malignancies unsuitable for limb-conserving surgery. However, little is known about the outcomes of this treatment in elderly patients. We sought to determine the effects of age on the tolerability and efficacy of ILP for advanced extremity malignancy. Patients undergoing ILP at our institution between January 2005 and January 2018 were identified from a prospectively maintained database. Patients were stratified by pathology (melanoma, soft-tissue sarcoma, other) and age (<75 years and ≥75 years). Outcomes of interest were perioperative morbidity and mortality, locoregional toxicities, response rates and oncological outcomes. During the study period, a total of 189 perfusions were attempted. Successful perfusions were performed in 179 patients, giving a technical success rate of 94.7%. No difference in perfusion success rates, severe locoregional toxicity and perioperative morbidity or mortality was noted between those aged <75 years and ≥75 years. The overall response rate in melanoma was 82.4%, and no difference in response rates or oncological outcomes between age groups was noted in these patients. The overall response rate in soft-tissue sarcoma was 63.5%, with no difference in response rates noted between age groups. However, patients aged <75 years with soft-tissue sarcoma had prolonged local recurrence-free survival compared with older patients (13 versus 6 months), possibly due to the prevalence of chemosensitive subtypes in the younger age group. ILP is an effective treatment for advanced extremity malignancies in the elderly, with comparable response rates and toxicities to younger patients. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.

The Effect Analysis of Strain Rate on Power Transmission Tower-Line System under Seismic Excitation

PubMed Central

Wang, Wenming

2014-01-01

The effect analysis of strain rate on power transmission tower-line system under seismic excitation is studied in this paper. A three-dimensional finite element model of a transmission tower-line system is created based on a real project. Using theoretical analysis and numerical simulation, incremental dynamic analysis of the power transmission tower-line system is conducted to investigate the effect of strain rate on the nonlinear responses of the transmission tower and line. The results show that the effect of strain rate on the transmission tower generally decreases the maximum top displacements, but it would increase the maximum base shear forces, and thus it is necessary to consider the effect of strain rate on the seismic analysis of the transmission tower. The effect of strain rate could be ignored for the seismic analysis of the conductors and ground lines, but the responses of the ground lines considering strain rate effect are larger than those of the conductors. The results could provide a reference for the seismic design of the transmission tower-line system. PMID:25105157

Effects of amplitude distortions and IF equalization on satellite communication system bit-error rate performance

NASA Technical Reports Server (NTRS)

Kerczewski, Robert J.; Fujikawa, Gene; Svoboda, James S.; Lizanich, Paul J.

1990-01-01

Satellite communications links are subject to distortions which result in an amplitude versus frequency response which deviates from the ideal flat response. Such distortions result from propagation effects such as multipath fading and scintillation and from transponder and ground terminal hardware imperfections. Bit-error rate (BER) degradation resulting from several types of amplitude response distortions were measured. Additional tests measured the amount of BER improvement obtained by flattening the amplitude response of a distorted laboratory simulated satellite channel. The results of these experiments are presented.

Further study on the wheel-rail impact response induced by a single wheel flat: the coupling effect of strain rate and thermal stress

NASA Astrophysics Data System (ADS)

Jing, Lin; Han, Liangliang

2017-12-01

A comprehensive dynamic finite-element simulation method was proposed to study the wheel-rail impact response induced by a single wheel flat based on a 3-D rolling contact model, where the influences of the structural inertia, strain rate effect of wheel-rail materials and thermal stress due to the wheel-rail sliding friction were considered. Four different initial conditions (i.e. pure mechanical loading plus rate-independent, pure mechanical loading plus rate-dependent, thermo-mechanical loading plus rate-independent, and thermo-mechanical loading plus rate-dependent) were involved into explore the corresponding impact responses in term of the vertical impact force, von-Mises equivalent stress, equivalent plastic strain and shear stress. Influences of train speed, flat length and axle load on the flat-induced wheel-rail impact response were discussed, respectively. The results indicate that the maximum thermal stresses are occurred on the tread of the wheel and on the top surface of the middle rail; the strain rate hardening effect contributes to elevate the von-Mises equivalent stress and restrain the plastic deformation; and the initial thermal stress due to the sliding friction will aggravate the plastic deformation of wheel and rail. Besides, the wheel-rail impact responses (i.e. impact force, von-Mises equivalent stress, equivalent plastic strain, and XY shear stress) induced by a flat are sensitive to the train speed, flat length and axle load.

Heart Rate Response and Lactic Acid Concentration in Squash Players.

ERIC Educational Resources Information Center

Beaudin, Paula; And Others

1978-01-01

It was concluded that playing squash is an activity that results in heart rate responses of sufficient intensity to elicit aerobic training effects without producing high lactic acid concentration in the blood. (MM)

Chronotropic and pressor effects of water ingestion at rest and in response to incremental dynamic exercise.

PubMed

Mendonca, Goncalo V; Teixeira, Micael S; Heffernan, Kevin S; Fernhall, Bo

2013-06-01

Ingestion of water attenuates the chronotropic response to submaximal exercise. However, it is not known whether this effect is equally manifested during dynamic exercise below and above the ventilatory threshold (VT). We explored the effects of water ingestion on the heart rate response to an incremental cycle-ergometer protocol. In a randomized fashion, 19 healthy adults (10 men and nine women, age 20.9 ± 1.8 years) ingested 50 and 500 ml of water before completing a cycle-ergometer protocol on two separate days. The heart rate and oxygen uptake ( ) responses to water ingestion were analysed both at rest and during exercise performed below and above the VT. The effects of water intake on brachial blood pressure were measured only at rest. Resting mean arterial pressure increased and resting heart rate decreased, but only after 500 ml of water (P < 0.05). Compared with that seen after 50 ml of water, the 500 ml volume elicited an overall decrease in submaximal heart rate (P < 0.05). In contrast, drinking 500 ml of water did not affect submaximal . The participants' maximal heart rate, maximal and VT were similar between conditions. Our results therefore indicate that, owing to its effects on submaximal heart rate over a broad spectrum of intensities, the drinking of water should be recognized as a potential confounder in cardiovascular exercise studies. However, by showing no differences between conditions for submaximal , they also suggest that the magnitude of heart rate reduction after drinking 500 ml of water may be of minimal physiological significance for exercise cardiorespiratory capacity.

Reviewing the Research on Mail Survey Response Rates: Meta-Analysis.

ERIC Educational Resources Information Center

Green, Kathy E.; Hutchinson, Susan R.

Meta-analysis, a way of cumulating the results of research studies, focuses on the magnitudes of effect sizes and seeks to explain effects through study characteristics. This meta-analysis used the methods developed by G. V. Glass to summarize the research on mail survey response rate manipulations. A narrative review using the same studies set…

Sublethal effects of cadmium on physiological responses in the pocketbook mussel, Lampsilis ventricosa

USGS Publications Warehouse

Naimo, T.J.; Atchison, G.J.; Holland Bartels, L. E.

1992-01-01

Several physiological responses have been used to evaluate the effects of contaminants on marine bivalves. Respiration rate, food clearance rate, ammonia excretion rate, and food assimilation efficiency can be quantified and incorporated into a bioenergetics model known as scope for growth. This model estimates an organism's instantaneous energy budget and quantifies the available energy for growth and reproduction. We applied some of these physiological techniques to freshwater mussels to determine the sublethal effects of cadmium. The objective of our study was to quantify the physiological responses of adult pocketbook mussels, Lampsilis ventricosa , exposed to sublethal concentrations of cadmium. We selected L. ventricosa for study because it is abundant in the upper Mississippi River and its life history has been partially documented.

What You Don't Know: Improving Family Health History Knowledge among Multigenerational Families of Mexican Origin.

PubMed

Goergen, Andrea F; Ashida, Sato; Skapinsky, Kaley; de Heer, Hendrik D; Wilkinson, Anna V; Koehly, Laura M

2016-01-01

This study investigated diabetes and heart disease family health history (FHH) knowledge and changes after providing personalized disease risk feedback. A total of 497 adults from 162 families of Mexican origin were randomized by household to conditions based on feedback recipient and content. Each provided personal and relatives' diabetes and heart disease diagnoses and received feedback materials following baseline assessment. Multivariate models were fitted to identify factors associated with the rate of 'don't know' FHH responses. At baseline, US nativity was associated with a higher 'don't know' response rate (p = 0.002). Though confounded by country of birth, younger age showed a trend toward higher 'don't know' response rates. Overall, average 'don't know' response rates dropped from 20 to 15% following receipt of feedback (p < 0.001). An intervention effect was noted, as 'don't know' response rates decreased more in households where one family member (vs. all) received supplementary risk assessments (without behavioral recommendations; p = 0.011). Limited FHH knowledge was noted among those born in the US and younger participants, representing a key population to reach with intervention efforts. The intervention effect suggests that 'less is more', indicating the potential for too much information to limit health education program effectiveness. © 2016 S. Karger AG, Basel.

Strain Rate Sensitivity of Epoxy Resin in Tensile and Shear Loading

NASA Technical Reports Server (NTRS)

Gilat, Amos; Goldberg, Robert K.; Roberts, Gary D.

2005-01-01

The mechanical response of E-862 and PR-520 resins is investigated in tensile and shear loadings. At both types of loading the resins are tested at strain rates of about 5x10(exp 5), 2, and 450 to 700 /s. In addition, dynamic shear modulus tests are carried out at various frequencies and temperatures, and tensile stress relaxation tests are conducted at room temperature. The results show that the toughened PR-520 resin can carry higher stresses than the untoughened E-862 resin. Strain rate has a significant effect on the response of both resins. In shear both resins show a ductile response with maximum stress that is increasing with strain rate. In tension a ductile response is observed at low strain rate (approx. 5x10(exp 5) /s), and brittle response is observed at the medium and high strain rates (2, and 700 /s). The hydrostatic component of the stress in the tensile tests causes premature failure in the E-862 resin. Localized deformation develops in the PR-520 resin when loaded in shear. An internal state variable constitutive model is proposed for modeling the response of the resins. The model includes a state variable that accounts for the effect of the hydrostatic component of the stress on the deformation.

Barium enema and CT volumetry for predicting pathologic response to preoperative chemoradiotherapy in rectal cancer patients.

PubMed

Murono, Koji; Kawai, Kazushige; Tsuno, Nelson H; Ishihara, Soichiro; Yamaguchi, Hironori; Sunami, Eiji; Kitayama, Joji; Watanabe, Toshiaki

2014-06-01

Preoperative chemoradiotherapy has been widely used for the prevention of local recurrence of locally advanced rectal cancer, and the effect of chemoradiotherapy is known to be associated with overall survival. We aimed to evaluate the association of the pathologic response grade with tumor recurrence rate after chemoradiotherapy, using radiographic analysis and the Response Evaluation Criteria in Solid Tumors as the parameters. This study was conducted at a single tertiary care institution in Japan. This was a retrospective cohort study of patients undergoing preoperative chemoradiotherapy. A total of 101 low rectal cancer patients receiving preoperative chemoradiotherapy from July 2004 to August 2012 were enrolled. The tumor reduction rate was measured with the use of traditional Response Evaluation Criteria in Solid Tumors, barium enema, and CT volumetry, and the correlation between the reduction rate and the pathologic response grade was examined. The tumor reduction rate assessed according to Response Evaluation Criteria in Solid Tumors showed no association with the pathologic response grade (p =0.61). In contrast, the radiographic response rate by both barium enema and CT volumetry strongly correlated with the pathologic response grade (p < 0.0001 and p = 0.001).In terms of local tumor recurrence, those diagnosed as high responders by the pathologic response grade, Response Evaluation Criteria in Solid Tumors, barium enema, and CT volumetry had a lower recurrence rate (p =0.03, p =0.03, p =0.0002, and p =0.001). The difference between high responders and low responders was especially prominent by barium enema and CT volumetry. The study is limited by its retrospective nature. Double-contrast barium enema and CT volumetry were superior to Response Evaluation Criteria in Solid Tumors in evaluating the effect of chemoradiotherapy and predicting the likelihood of tumor recurrence.

Variable effects of temperature on insect herbivory

PubMed Central

Burkepile, Deron E.; Parker, John D.

2014-01-01

Rising temperatures can influence the top-down control of plant biomass by increasing herbivore metabolic demands. Unfortunately, we know relatively little about the effects of temperature on herbivory rates for most insect herbivores in a given community. Evolutionary history, adaptation to local environments, and dietary factors may lead to variable thermal response curves across different species. Here we characterized the effect of temperature on herbivory rates for 21 herbivore-plant pairs, encompassing 14 herbivore and 12 plant species. We show that overall consumption rates increase with temperature between 20 and 30 °C but do not increase further with increasing temperature. However, there is substantial variation in thermal responses among individual herbivore-plant pairs at the highest temperatures. Over one third of the herbivore-plant pairs showed declining consumption rates at high temperatures, while an approximately equal number showed increasing consumption rates. Such variation existed even within herbivore species, as some species exhibited idiosyncratic thermal response curves on different host plants. Thus, rising temperatures, particularly with respect to climate change, may have highly variable effects on plant-herbivore interactions and, ultimately, top-down control of plant biomass. PMID:24860701

Health Science students' evaluation of courses and Instructors: the effect of response rate and class size interaction.

PubMed

Kuwaiti, Ahmed Al

2015-01-01

This study aims at investigating the effect of response rate and class size interaction on students' evaluation of instructors and the courses offered at heath science colleges in Saudi Arabia. A retrospective study design was adapted to ascertain Course Evaluation Surveys (CES) conducted at the health science colleges of the University of Dammam [UOD] in the academic year 2013-2014. Accordingly, the CES data which was downloaded from an exclusive online application 'UDQUEST' which includes 337 different courses and 15,264 surveys were utilized in this study. Two-way analysis of variance was utilized to test whether there is any significant interaction between the class size and the response rate on the students' evaluation of courses and instructors. The study showed that high response rate is required for student evaluation of instructors at Health Science colleges when the class size is small whereas a medium response rate is required for students' evaluation of courses. On the other hand, when the class size is medium, a medium or high response rate is needed for students' evaluation of both instructors and courses. The results of this study recommend that the administrators of the health science colleges to be aware of the interpretation of students' evaluations of courses and instructors. The study also suggests that the interaction between response rate and class size is a very important factor that needs to be taken into consideration while interpreting the findings of the students' evaluation of instructors and courses.

Subjective health complaints and self-rated health: are expectancies more important than socioeconomic status and workload?

PubMed

Ree, Eline; Odeen, Magnus; Eriksen, Hege R; Indahl, Aage; Ihlebæk, Camilla; Hetland, Jørn; Harris, Anette

2014-06-01

The associations between socioeconomic status (SES), physical and psychosocial workload and health are well documented. According to The Cognitive Activation Theory of Stress (CATS), learned response outcome expectancies (coping, helplessness, and hopelessness) are also important contributors to health. This is in part as independent factors for health, but coping may also function as a buffer against the impact different demands have on health. The purpose of this study was to investigate the relative effect of SES (as measured by level of education), physical workload, and response outcome expectancies on subjective health complaints (SHC) and self-rated health, and if response outcome expectancies mediate the effects of education and physical workload on SHC and self-rated health. A survey was carried out among 1,746 Norwegian municipal employees (mean age 44.2, 81 % females). Structural Equation Models with SHC and self-rated health as outcomes were conducted. Education, physical workload, and response outcome expectancies, were the independent 28 variables in the model. Helplessness/hopelessness had a stronger direct effect on self-rated health and SHC than education and physical workload, for both men and women. Helplessness/hopelessness fully mediated the effect of physical workload on SHC for men (0.121), and mediated 30 % of a total effect of 0.247 for women. For women, education had a small but significant indirect effect through helplessness/hopelessness on self-rated health (0.040) and SHC (-0.040), but no direct effects were found. For men, there was no effect of education on SHC, and only a direct effect on self-rated health (0.134). The results indicated that helplessness/hopelessness is more important for SHC and health than well-established measures on SES such as years of education and perceived physical workload in this sample. Helplessness/hopelessness seems to function as a mechanism between physical workload and health.

Effects of the Sports Level, Format of the Game and Task Condition on Heart Rate Responses, Technical and Tactical Performance of Youth Basketball Players

PubMed Central

Clemente, Filipe Manuel; González-Víllora, Sixto; Delextrat, Anne; Martins, Fernando Manuel Lourenço; Vicedo, Juan Carlos Pastor

2017-01-01

Abstract The aim of this study was to analyze the effect of different small-sided and conditioning games (SSCG) with different tactical contents on heart rate responses, technical performance and collective organization of youth basketball players of different performance levels. Twenty male basketball players from U14 (13.7 ± 0.8 years old; 4.2 ± 1.4 years of practice) and U16 (15.3 ± 1.1 years old; 6.4 ± 2.1 years of practice) participated in this research study. The two-way MANOVA revealed that the sports level (p = 0.009; ηp2 = 0.151), format (p = 0.001; ηp2 = 0.246) and task condition (p = 0.023; ηp2 = 0.104; small effect size) had significant main effects on heart rate responses. It was also found that the format (p = 0.001; ηp2 = 0.182) had significant main effects on technical performance. A smaller format significantly increased the heart rate, volume of play, efficiency index and collective density during attacking plays. The SSCG with attacking content statistically increased the heart rate, efficiency index and performance score. Therefore, this study revealed that different SSCGs with tactical content influenced the physiological responses of youth players. PMID:28828085

Response and Remission After Cognitive and Exposure Therapy for Hypochondriasis.

PubMed

Weck, Florian; Neng, Julia M B

2015-11-01

Cognitive behavioral therapy has demonstrated large effect sizes for the treatment of hypochondriasis. However, response and remission rates, which provide important additional information about clinically significant improvements, have seldom been reported. In the current study, rates of response and remission after cognitive therapy and exposure therapy were evaluated. The study was based on a randomized controlled trial that treated patients with hypochondriasis (N = 75). The primary outcome measure was a clinician-administered structured interview for hypochondriasis. At posttreatment, response was found for 72.0% and remission for 45.3% of the patients. At 12-month follow-up, the response rate was 68.0%, and the remission rate was 54.7%. No significant differences in the frequency of response/remission were found between the cognitive therapy and the exposure therapy groups. Patients' and therapists' perspectives of clinical improvement corresponded with remission rather than response rates. Improvement rates were compared with those of other mental disorders, and implications for the treatment of hypochondriasis were discussed.

Habituation and sensitization of aggression in bullfrogs (Rana catesbeiana): testing the dual-process theory of habituation.

PubMed

Bee, M A

2001-09-01

The aggressive response of male bullfrogs (Rana catesbeiana) habituates with repeated broadcasts of acoustic stimuli simulating a new territorial neighbor. The effects of stimulus repetition rate and stimulus intensity on bullfrog aggressive responses were tested in a field experiment designed to test the assumptions of a dual-process theory of habituation. Synthetic advertisement calls were broadcast at 2 repetition rates and 2 intensities in a factorial design. Bullfrogs were more aggressive at the higher stimulus intensity at both repetition rates. Aggressive responses habituated more slowly at the higher stimulus intensity and slower repetition rate compared with other treatments. Several biotic and abiotic factors had small or negligible effects on aggressive responses. Although consistent with the operation of 2 opposing processes, habituation and sensitization, the data provide only partial support for the assumptions of dual-process theory.

Incorporation of Mean Stress Effects into the Micromechanical Analysis of the High Strain Rate Response of Polymer Matrix Composites

NASA Technical Reports Server (NTRS)

Goldberg, Robert K.; Roberts, Gary D.; Gilat, Amos

2002-01-01

The results presented here are part of an ongoing research program, to develop strain rate dependent deformation and failure models for the analysis of polymer matrix composites subject to high strain rate impact loads. A micromechanics approach is employed in this work, in which state variable constitutive equations originally developed for metals have been modified to model the deformation of the polymer matrix, and a strength of materials based micromechanics method is used to predict the effective response of the composite. In the analysis of the inelastic deformation of the polymer matrix, the definitions of the effective stress and effective inelastic strain have been modified in order to account for the effect of hydrostatic stresses, which are significant in polymers. Two representative polymers, a toughened epoxy and a brittle epoxy, are characterized through the use of data from tensile and shear tests across a variety of strain rates. Results computed by using the developed constitutive equations correlate well with data generated via experiments. The procedure used to incorporate the constitutive equations within a micromechanics method is presented, and sample calculations of the deformation response of a composite for various fiber orientations and strain rates are discussed.

A Feedback Model of Attention Explains the Diverse Effects of Attention on Neural Firing Rates and Receptive Field Structure.

PubMed

Miconi, Thomas; VanRullen, Rufin

2016-02-01

Visual attention has many effects on neural responses, producing complex changes in firing rates, as well as modifying the structure and size of receptive fields, both in topological and feature space. Several existing models of attention suggest that these effects arise from selective modulation of neural inputs. However, anatomical and physiological observations suggest that attentional modulation targets higher levels of the visual system (such as V4 or MT) rather than input areas (such as V1). Here we propose a simple mechanism that explains how a top-down attentional modulation, falling on higher visual areas, can produce the observed effects of attention on neural responses. Our model requires only the existence of modulatory feedback connections between areas, and short-range lateral inhibition within each area. Feedback connections redistribute the top-down modulation to lower areas, which in turn alters the inputs of other higher-area cells, including those that did not receive the initial modulation. This produces firing rate modulations and receptive field shifts. Simultaneously, short-range lateral inhibition between neighboring cells produce competitive effects that are automatically scaled to receptive field size in any given area. Our model reproduces the observed attentional effects on response rates (response gain, input gain, biased competition automatically scaled to receptive field size) and receptive field structure (shifts and resizing of receptive fields both spatially and in complex feature space), without modifying model parameters. Our model also makes the novel prediction that attentional effects on response curves should shift from response gain to contrast gain as the spatial focus of attention drifts away from the studied cell.

Influence of Effective Communication by Surgery Students on Their Oral Examination Scores.

ERIC Educational Resources Information Center

Rowland-Morin, Pamela A.; And Others

1991-01-01

Clinical surgery faculty (n=78) evaluated videotaped simulated surgery student oral examinations. Results showed that regardless of the content of students' responses, evaluators were strongly influenced by how well students communicated. Evaluators preferred a moderate response rate and direct eye contact over a slower response rate and indirect…

Diverging temperature responses of CO2 assimilation and plant development explain the overall effect of temperature on biomass accumulation in wheat leaves and grains

PubMed Central

Lohraseb, Iman; Collins, Nicholas C.

2017-01-01

Abstract There is a growing consensus in the literature that rising temperatures influence the rates of biomass accumulation by shortening the development of plant organs and the whole plant and by altering the rates of respiration and photosynthesis. A model describing the net effects of these processes on biomass would be useful, but would need to reconcile reported differences in the effects of night and day temperature on plant productivity. In this study, the working hypothesis was that the temperature responses of CO2 assimilation and plant development rates were divergent, and that their net effects could explain observed differences in biomass accumulation. In wheat (Triticum aestivum) plants, we followed the temperature responses of photosynthesis, respiration and leaf elongation, and confirmed that their responses diverged. We measured the amount of carbon assimilated per ‘unit of plant development’ in each scenario and compared it to the biomass that accumulated in growing leaves and grains. Our results suggested that, up to a temperature optimum, the rate of any developmental process increased with temperature more rapidly than that of CO2 assimilation and that this discrepancy, summarised by the CO2 assimilation rate per unit of plant development, could explain the observed reductions in biomass accumulation in plant organs under high temperatures. The model described the effects of night and day temperature equally well, and offers a simple framework for describing the effects of temperature on plant growth. PMID:28069595

Impact of CYP2D6 polymorphisms on clinical efficacy & tolerability of metoprolol tartrate

PubMed Central

Hamadeh, Issam S.; Langaee, Taimour Y.; Dwivedi, Ruti; Garcia, Sofia; Burkley, Ben M.; Chapman, Arlene B.; Gums, John G.; Turner, Stephen T.; Gong, Yan; Cooper-DeHoff, Rhonda M.; Johnson, Julie A.

2014-01-01

Metoprolol is a selective β-1 adrenergic receptor blocker that undergoes extensive metabolism by the polymorphic enzyme, CYP2D6. Our objective was to investigate the influence of CYP2D6 polymorphisms on efficacy and tolerability of metoprolol tartrate. 281 study participants with uncomplicated hypertension received 50 mg of metoprolol twice daily followed by response guided titration to 100 mg twice daily. Phenotypes were assigned based on results of CYP2D6 genotyping and copy number variation assays. Clinical response to metoprolol and adverse effect rates were analyzed in relation to CYP2D6 phenotypes by using appropriate statistical tests. Heart rate response differed significantly by CYP2D6 phenotype (p-value <0.0001) with poor metabolizers & intermediate metabolizers showing greater HR reduction. However, blood pressure response and adverse effect rates were not significantly different by CYP2D6 phenotype. Other than a significant difference in heart rate response, CYP2D6 polymorphisms were not a determinant of the variability in response or tolerability to metoprolol. PMID:24637943

Soil microbial responses to nitrogen addition in arid ecosystems

DOE PAGES

Sinsabaugh, Robert L.; Belnap, Jayne; Rudgers, Jennifer; ...

2015-08-14

The N cycle of arid ecosystems is influenced by low soil organic matter, high soil pH, and extremes in water potential and temperature that lead to open canopies and development of biological soil crusts (biocrusts). We investigated the effects of N amendment on soil microbial dynamics in a Larrea tridentata-Ambrosia dumosa shrubland site in southern Nevada USA. Sites were fertilized with a NO 3-NH 4 mix at 0, 7, and 15 kg N ha -1 y -1 from March 2012 to March 2013. In March 2013, biocrust (0–0.5 cm) and bulk soils (0–10 cm) were collected beneath Ambrosia canopies andmore » in the interspaces between plants. Biomass responses were assessed as bacterial and fungal SSU rRNA gene copy number and chlorophyll a concentration. Metabolic responses were measured by five ecoenzyme activities and rates of N transformation. By most measures, nutrient availability, microbial biomass, and process rates were greater in soils beneath the shrub canopy compared to the interspace between plants, and greater in the surface biocrust horizon compared to the deeper 10 cm soil profile. Most measures responded positively to experimental N addition. Effect sizes were generally greater for bulk soil than biocrust. Results were incorporated into a meta-analysis of arid ecosystem responses to N amendment that included data from 14 other studies. Effect sizes were calculated for biomass and metabolic responses. Regressions of effect sizes, calculated for biomass, and metabolic responses, showed similar trends in relation to N application rate and N load (rate × duration). The critical points separating positive from negative treatment effects were 88 kg ha -1 y -1 and 159 kg ha -1, respectively, for biomass, and 70 kg ha -1 y -1 and 114 kg ha -1, respectively, for metabolism. These critical values are comparable to those for microbial biomass, decomposition rates and respiration reported in broader meta-analyses of N amendment effects in mesic ecosystems. As a result, large effect sizes at low N addition rates indicate that arid ecosystems are sensitive to modest increments in anthropogenic N deposition.« less

The effectiveness of a monetary incentive offer on survey response rates and response completeness in a longitudinal study.

PubMed

Yu, Shengchao; Alper, Howard E; Nguyen, Angela-Maithy; Brackbill, Robert M; Turner, Lennon; Walker, Deborah J; Maslow, Carey B; Zweig, Kimberly C

2017-04-26

Achieving adequate response rates is an ongoing challenge for longitudinal studies. The World Trade Center Health Registry is a longitudinal health study that periodically surveys a cohort of ~71,000 people exposed to the 9/11 terrorist attacks in New York City. Since Wave 1, the Registry has conducted three follow-up surveys (Waves 2-4) every 3-4 years and utilized various strategies to increase survey participation. A promised monetary incentive was offered for the first time to survey non-respondents in the recent Wave 4 survey, conducted 13-14 years after 9/11. We evaluated the effectiveness of a monetary incentive in improving the response rate five months after survey launch, and assessed whether or not response completeness was compromised due to incentive use. The study compared the likelihood of returning a survey for those who received an incentive offer to those who did not, using logistic regression models. Among those who returned surveys, we also examined whether those receiving an incentive notification had higher rate of response completeness than those who did not, using negative binomial regression models and logistic regression models. We found that a $10 monetary incentive offer was effective in increasing Wave 4 response rates. Specifically, the $10 incentive offer was useful in encouraging initially reluctant participants to respond to the survey. The likelihood of returning a survey increased by 30% for those who received an incentive offer (AOR = 1.3, 95% CI: 1.1, 1.4), and the incentive increased the number of returned surveys by 18%. Moreover, our results did not reveal any significant differences on response completeness between those who received an incentive offer and those who did not. In the face of the growing challenge of maintaining a high response rate for the World Trade Center Health Registry follow-up surveys, this study showed the value of offering a monetary incentive as an additional refusal conversion strategy. Our findings also suggest that an incentive offer could be particularly useful near the end of data collection period when an immediate boost in response rate is needed.

Parental care mitigates carry-over effects of poor early conditions on offspring growth

USGS Publications Warehouse

Auer, Sonya K.; Martin, Thomas E.

2017-01-01

Poor developmental conditions can have long-lasting negative effects on offspring phenotypes, but impacts often differ among species. Contrasting responses may reflect disparities in experimental protocols among single-species studies or inherent differences among species in their sensitivity to early conditions and/or ability to mitigate negative impacts. We used a common experimental protocol to assess and compare the role of parental care in mitigating effects of poor early conditions on offspring among 4 sympatric bird species in the wild. We experimentally induced low incubation temperatures and examined effects on embryonic developmental rates, hatching success, nestling growth rates, and parental responses. We examined the generality of these effects across 4 species that differ in their phylogenetic history, breeding ecology, and life histories. We found that cooling led to delayed hatching in all species, but carry-over effects on offspring differed among species. Parents of some but not all species increased their offspring provisioning rates in response to experimental cooling with critical benefits for offspring growth rates. Our study shows for the first time that species exhibit clear differences in the degree to which they are affected by poor early conditions. Observed differences among species demonstrate that parental care is a critical mechanism for mitigating potential negative effects on offspring and suggest that parental responses may be constrained to varying degrees by ecology and life histories.

RESPONSIVENESS OF THE ACTIVITIES OF DAILY LIVING SCALE OF THE KNEE OUTCOME SURVEY AND NUMERIC PAIN RATING SCALE IN PATIENTS WITH PATELLOFEMORAL PAIN

PubMed Central

Piva, Sara R.; Gil, Alexandra B.; Moore, Charity G.; Fitzgerald, G. Kelley

2016-01-01

Objective To assess internal and external responsiveness of the Activity of Daily Living Scale of the Knee Outcome Survey and Numeric Pain Rating Scale on patients with patellofemoral pain. Design One group pre-post design. Subjects A total of 60 individuals with patellofemoral pain (33 women; mean age 29.9 (standard deviation 9.6) years). Methods The Activity of Daily Living Scale and the Numeric Pain Rating Scale were assessed before and after 8 weeks of physical therapy program. Patients completed a global rating of change scale at the end of therapy. The standardized effect size, Guyatt responsiveness index, and the minimum clinical important difference were calculated. Results Standardized effect size of the Activity of Daily Living Scale was 0.63, Guyatt responsiveness index was 1.4, area under the curve was 0.83 (95% confidence interval: 0.72, 0.94), and the minimum clinical important difference corresponded to an increase of 7.1 percentile points. Standardized effect size of the Numeric Pain Rating Scale was 0.72, Guyatt responsiveness index was 2.2, area under the curve was 0.80 (95% confidence interval: 0.70, 0.92), and the minimum clinical important difference corresponded to a decrease of 1.16 points. Conclusion Information from this study may be helpful to therapists when evaluating the effectiveness of rehabilitation intervention on physical function and pain, and to power future clinical trials on patients with patellofemoral pain. PMID:19229444

Responsiveness of the activities of daily living scale of the knee outcome survey and numeric pain rating scale in patients with patellofemoral pain.

PubMed

Piva, Sara R; Gil, Alexandra B; Moore, Charity G; Fitzgerald, G Kelley

2009-02-01

To assess internal and external responsiveness of the Activity of Daily Living Scale of the Knee Outcome Survey and Numeric Pain Rating Scale on patients with patellofemoral pain. One group pre-post design. A total of 60 individuals with patellofemoral pain (33 women; mean age 29.9 (standard deviation 9.6) years). The Activity of Daily Living Scale and the Numeric Pain Rating Scale were assessed before and after 8 weeks of physical therapy program. Patients completed a global rating of change scale at the end of therapy. The standardized effect size, Guyatt responsiveness index, and the minimum clinical important difference were calculated. Standardized effect size of the Activity of Daily Living Scale was 0.63, Guyatt responsiveness index was 1.4, area under the curve was 0.83 (95% confidence interval: 0.72, 0.94), and the minimum clinical important difference corresponded to an increase of 7.1 percentile points. Standardized effect size of the Numeric Pain Rating Scale was 0.72, Guyatt responsiveness index was 2.2, area under the curve was 0.80 (95% confidence interval: 0.70, 0.92), and the minimum clinical important difference corresponded to a decrease of 1.16 points. Information from this study may be helpful to therapists when evaluating the effectiveness of rehabilitation intervention on physical function and pain, and to power future clinical trials on patients with patellofemoral pain.

Understanding the Effect of Response Rate and Class Size Interaction on Students Evaluation of Teaching in a Higher Education

ERIC Educational Resources Information Center

Al Kuwaiti, Ahmed; AlQuraan, Mahmoud; Subbarayalu, Arun Vijay

2016-01-01

Objective: This study aims to investigate the interaction between response rate and class size and its effects on students' evaluation of instructors and the courses offered at a higher education Institution in Saudi Arabia. Study Design: A retrospective study design was chosen. Methods: One thousand four hundred and forty four different courses…

Atomoxetine in patients with ADHD: A clinical and pharmacological review of the onset, trajectory, duration of response and implications for patients.

PubMed

Clemow, David B; Bushe, Chris J

2015-12-01

This article reviews data providing new insight into the trajectory of response and maintenance of response of atomoxetine in the treatment of child and adult attention-deficit hyperactivity disorder (ADHD). This nonsystematic review includes: onset of action and duration of effect, response rate, effect size, time to optimal response and norepinephrine transporter blockade biomarker data. Atomoxetine can have an onset of action within 1-2 weeks of starting treatment, but there is an incrementally increasing response for up to 24 weeks or longer. Responder rates and effect sizes are similar to methylphenidate. Upon treatment discontinuation, relapse rates are lower than expected. In adults, 50% maintain their response for at least 6 months after stopping atomoxetine, following 6 months of treatment. Single-dose atomoxetine can provide 24-hour efficacy, despite a 5-hour plasma half-life. Hypotheses can be generated relating to neuroadaptive changes, to explain these findings. Atomoxetine has a trajectory of response that is incremental over a long period of time, with a greater than expected maintenance of response. This has implications for physician atomoxetine dosing and efficacy assessment, patient education and outcomes, and for clinical trial design and assessment of comparative efficacy with stimulant medications. © The Author(s) 2015.

Systematic Review and Meta-analysis: Placebo Rates in Induction and Maintenance Trials of Ulcerative Colitis

PubMed Central

Zou, Guangyong; Parker, Claire E.; Macdonald, John K.; Mosli, Mahmoud H.; Khanna, Reena; Shackelton, Lisa M.; Vandervoort, Margaret K.; AlAmeel, Turki; Al Beshir, Mohammad; AlMadi, Majid; Al-Taweel, Talal; Atkinson, Nathan S. S.; Biswas, Sujata; Chapman, Thomas P.; Dulai, Parambir S.; Glaire, Mark A.; Hoekman, Daniel; Koutsoumpas, Andreas; Minas, Elizabeth; Samaan, Mark A.; Travis, Simon; D’Haens, Geert; Levesque, Barrett G.; Sandborn, William J.; Feagan, Brian G.

2016-01-01

Background and Aims: Minimisation of the placebo responses in randomised controlled trials [RCTs] is essential for efficient evaluation of new interventions. Placebo rates have been high in ulcerative colitis [UC] clinical trials, and factors influencing this are poorly understood. We quantify placebo response and remission rates in UC RCTs and identify trial design factors influencing them. Methods: MEDLINE, EMBASE, and the Cochrane Library were searched from inception through April 2014 for placebo-controlled trials in adult patients with UC of a biological agent, corticosteroid, immunosuppressant, or aminosalicylate. Data were independently doubly extracted. Quality was assessed using the Cochrane risk of bias tool. Results: In all, 51 trials [48 induction and 10 maintenance phases] were identified. Placebo response and remission rates were pooled according to random-effects models, and mixed-effects meta-regression models were used to evaluate effects of study-level characteristics on these rates. Pooled estimates of placebo remission and response rates for induction trials were 10% (95% confidence interval [CI] 7-13%) and 33% [95% CI 29-37%], respectively. Corresponding values for maintenance trials were 19% [95% CI 11-30%] and 22% [95% CI 17-28%]. Trials enrolling patients with more active disease confirmed by endoscopy [endoscopy subscore ≥ 2] were associated with lower placebo rates. Conversely, placebo rates increased with increasing trial duration and number of study visits. Conclusions: Objective assessment of greater disease activity at trial entry by endoscopy lowered placebo rates, whereas increasing trial duration and more interactions with healthcare providers increased placebo rates. These findings have important implications for design and conduct of clinical trials. PMID:26746169

Smoking and immunomodulators do not influence the response or duration of response to infliximab in Crohn's disease.

PubMed

Fefferman, David S; Lodhavia, Parag J; Alsahli, Mazen; Falchuk, Kenneth R; Peppercorn, Mark A; Shah, Samir A; Farrell, Richard J

2004-07-01

Clinical predictors for infliximab response are still unknown. Identifying predictors of response to infliximab in Crohn's disease may improve our selection of patients. Two hundred patients with luminal (61%) or fistulous (39%) Crohn's disease and at least 6 months of follow-up following a total of 416 infliximab infusions were evaluated. Clinical response and duration of response were the primary endpoints. Patients with fistulous disease had a higher response rate (83% versus 70%, P = 0.044) and a significantly longer duration of response compared with patients with luminal disease (17.4 versus 10.1 wks, P = 0.017). For luminal disease, nonsmokers and smokers had similar response rates (74% versus 64%, P = 0.5) and similar durations of response (9.4 wks versus 8.4 wks P = 0.6) while patients taking concurrent immunomodulators had similar response rates compared with those not taking immunomodulators (74% versus 71%, P = 0.9) and similar durations of response (10.4 wks versus 10.6 wks, P = 0.9). For fistulous disease, response rates (89% versus 83% P = 0.9) and duration of response (16.9 wks versus 10.1 wks, P = 0.10) were similar between nonsmokers and smokers and concurrent immunomodulators had no effect on response (89% versus 86%, P = 0.9) or duration of response (19.8 wks versus 15.4 wks, P = 0.46). Multivariable analysis confirmed that neither smoking, corticosteroids, immunomodulator therapy, gender, age, age of disease onset, disease duration, nor luminal disease location significantly influenced response or duration of response. Patients with fistulous disease had a higher response rate and a significantly longer duration of response compared with patients with luminal disease. However, among patients with luminal or fistulous disease, neither smoking nor immunomodulators had any effect on response or duration of response.

Rate of Conditioned Reinforcement Affects Observing Rate but Not Resistance to Change

ERIC Educational Resources Information Center

Shahan, Timothy A.; Podlesnik, Christopher A.

2005-01-01

The effects of rate of conditioned reinforcement on the resistance to change of operant behavior have not been examined. In addition, the effects of rate of conditioned reinforcement on the rate of observing have not been adequately examined. In two experiments, a multiple schedule of observing-response procedures was used to examine the effects…

High Strain-Rate and Temperature Effects on the Response of Composites

NASA Technical Reports Server (NTRS)

Gilat, Amos

2004-01-01

The objective of the research is to expand the experimental study of the effect of strain rate on mechanical response (deformation and failure) of epoxy resins and carbon fibers/epoxy matrix composites, to include elevated temperature tests. The experimental data provide the information needed for NASA scientists for the development of a nonlinear, strain rate and temperature dependent deformation and strength models for composites that can subsequently be used in design. This year effort was directed into the development and testing of the epoxy resin at elevated temperatures. Two types of epoxy resins were tested in shear at high strain rates of about 700 per second and elevated temperatures of 50 and 80 C. The results show that the temperature significantly affects the response of epoxy.

Listening to urban soundscapes: Physiological validity of perceptual dimensions.

PubMed

Irwin, Amy; Hall, Deborah A; Peters, Andrew; Plack, Christopher J

2011-02-01

Predominantly, the impact of environmental noise is measured using sound level, ignoring the influence of other factors on subjective experience. The present study tested physiological responses to natural urban soundscapes, using functional magnetic resonance imaging and vector cardiogram. City-based recordings were matched in overall sound level (71 decibel A-weighted scale), but differed on ratings of pleasantness and vibrancy. Listening to soundscapes evoked significant activity in a number of auditory brain regions. Compared with soundscapes that evoked no (neutral) emotional response, those evoking a pleasant or unpleasant emotional response engaged an additional neural circuit including the right amygdala. Ratings of vibrancy had little effect overall, and brain responses were more sensitive to pleasantness than was heart rate. A novel finding is that urban soundscapes with similar loudness can have dramatically different effects on the brain's response to the environment. Copyright © 2010 Society for Psychophysiological Research.

Switch Rates During Acute Treatment for Bipolar II Depression With Lithium, Sertraline, or the Two Combined: A Randomized Double-Blind Comparison.

PubMed

Altshuler, Lori L; Sugar, Catherine A; McElroy, Susan L; Calimlim, Brian; Gitlin, Michael; Keck, Paul E; Aquino-Elias, Ana; Martens, Brian E; Fischer, E Grace; English, Teri L; Roach, Janine; Suppes, Trisha

2017-03-01

The authors compared medication-induced mood switch risk (primary outcome), as well as treatment response and side effects (secondary outcomes) with three acute-phase treatments for bipolar II depression. In a 16-week, double-blind, multisite comparison study, 142 participants with bipolar II depression were randomly assigned to receive lithium monotherapy (N=49), sertraline monotherapy (N=45), or combination treatment with lithium and sertraline (N=48). At each visit, mood was assessed using standardized rating scales. Rates of switch were compared, as were rates of treatment response and the presence and severity of treatment-emergent side effects. Twenty participants (14%) experienced a switch during the study period (hypomania, N=17; severe hypomania, N=3). Switch rates did not differ among the three treatment groups, even after accounting for dropout. No patient had a manic switch or was hospitalized for a switch. Most switches occurred within the first 5 weeks of treatment. The treatment response rate for the overall sample was 62.7% (N=89), without significant differences between groups after accounting for dropout. The lithium/sertraline combination group had a significantly higher overall dropout rate than the monotherapy groups but did not have an accelerated time to response. Lithium monotherapy, sertraline monotherapy, and lithium/sertraline combination therapy were associated with similar switch and treatment response rates in participants with bipolar II depression. The dropout rate was higher in the lithium/sertraline combination treatment group, without any treatment acceleration advantage.

Patterns of Symptomatic Recovery in Psychotherapy.

ERIC Educational Resources Information Center

Kopta, Stephen Mark; And Others

1994-01-01

Used psychotherapy dosage model in which effect was probability of recovery to compare treatment response rates for psychological symptoms. Administered symptom checklists to 854 psychotherapy outpatients at intake and during treatment. Chronic distress symptoms demonstrated fastest average response rate, whereas characterological symptoms…

Computational Simulation of the High Strain Rate Tensile Response of Polymer Matrix Composites

NASA Technical Reports Server (NTRS)

Goldberg, Robert K.

2002-01-01

A research program is underway to develop strain rate dependent deformation and failure models for the analysis of polymer matrix composites subject to high strain rate impact loads. Under these types of loading conditions, the material response can be highly strain rate dependent and nonlinear. State variable constitutive equations based on a viscoplasticity approach have been developed to model the deformation of the polymer matrix. The constitutive equations are then combined with a mechanics of materials based micromechanics model which utilizes fiber substructuring to predict the effective mechanical and thermal response of the composite. To verify the analytical model, tensile stress-strain curves are predicted for a representative composite over strain rates ranging from around 1 x 10(exp -5)/sec to approximately 400/sec. The analytical predictions compare favorably to experimentally obtained values both qualitatively and quantitatively. Effective elastic and thermal constants are predicted for another composite, and compared to finite element results.

Covariates of the Rating Process in Hierarchical Models for Multiple Ratings of Test Items

ERIC Educational Resources Information Center

Mariano, Louis T.; Junker, Brian W.

2007-01-01

When constructed response test items are scored by more than one rater, the repeated ratings allow for the consideration of individual rater bias and variability in estimating student proficiency. Several hierarchical models based on item response theory have been introduced to model such effects. In this article, the authors demonstrate how these…

What you don’t know…: Improving family health history knowledge among multigenerational Mexican origin families

PubMed Central

Goergen, Andrea F.; Ashida, Sato; Skapinsky, Kaley; de Heer, Hendrik D.; Wilkinson, Anna V.; Koehly, Laura M.

2016-01-01

Background This study investigated diabetes (DB) and heart disease (HD) family health history (FHH) knowledge and changes following provision of personalized disease risk feedback. Methods 497 adults from 162 Mexican-origin families were randomized by household to conditions based on feedback recipient and content. Each provided personal and relatives’ DB and HD diagnoses and received feedback materials following baseline assessment. Multivariate models were fitted to identify factors associated with the rate of “don’t know” FHH responses. Results At baseline U.S. nativity was associated with a higher “don’t know” response rate (p=0.002). Though confounded by country of birth, younger age showed a trend toward higher “don’t know” response rates. Overall, average “don’t know” response rates dropped from 20% to 15% following receipt of feedback (p<0.001). An intervention effect was noted, as “don’t know” response rates decreased more in households where one family member (vs all) received supplementary risk assessments (without behavioral recommendations) (p=0.011). Conclusions Limited FHH knowledge was noted among those born in the US and younger participants, representing a key population to reach with intervention efforts. The intervention effect suggests that “less is more” indicating the potential for too much information to limit health education program effectiveness. PMID:26854931

Mode of delivery, but not questionnaire length, affected response in an epidemiological study of eating-disordered behavior.

PubMed

Mond, J M; Rodgers, B; Hay, P J; Owen, C; Beumont, P J V

2004-11-01

The effects of questionnaire length and mode of delivery on response rates were examined in an epidemiological study of eating-disordered behavior. Short (8 pages) and long (14 pages) questionnaires were posted or hand-delivered to a community sample of 802 women. Nonrespondents who received the first questionnaire by hand delivery received a reminder letter and replacement questionnaire by post; those who received the initial questionnaire by post were further randomized to receive the first reminder by hand delivery or by post, in short or long form. A second reminder letter and questionnaire (in short or long form) were posted to all remaining nonrespondents. The overall response rate was 52.9%. This is a conservative estimate of true response, because in a substantial proportion of cases (12.2%) individuals were no longer resident at the listed address. There was a significant effect of mode of delivery on response, favoring hand delivery, at both the initial mailout and first reminder. There was no effect of questionnaire length on response to the initial mailout, although overall response was significantly higher for the longer form. It was estimated that an overall response of 58.0% would have been achieved had first reminders been hand-delivered to all nonrespondents who received the initial mailout by post. Delivery of questionnaires by hand may be an effective way to increase response rates in epidemiological research, but little is to be gained by reducing questionnaire length.

Within-Subject Testing of the Signaled-Reinforcement Effect on Operant Responding as Measured by Response Rate and Resistance to Change

ERIC Educational Resources Information Center

Reed, Phil; Doughty, Adam H.

2005-01-01

Response rates under random-interval schedules are lower when a brief (500 ms) signal accompanies reinforcement than when there is no signal. The present study examined this signaled-reinforcement effect and its relation to resistance to change. In Experiment 1, rats responded on a multiple random-interval 60-s random-interval 60-s schedule, with…

[The significance of a reminder and physician's motivation for the response rate of a questionnaire survey in general practice].

PubMed

Vedsted, P; Mainz, J; Olesen, F

2001-10-01

The use of a mailed reminder to improve the response rate in a questionnaire survey was analysed in a general practice multicentre survey in Denmark, Norway, and the Netherlands. In total 14 general practitioners (GP's) handed out the questionnaire to 650 adult patients. A randomized sample of the patients who did not respond after three weeks received a reminder including a new questionnaire. In the group that received a reminder the response rate was significantly higher compared with the group that did not (79% vs. 62%). In Denmark, two of the four participating GP's were specially motivated. The response rate for these GP's was significantly higher compared to the normally motivated GP's (91% vs. 71%). Specially motivated GP's can increase the response rate and thereby minimise the effect of the reminder.

Nonlinearity and Strain-Rate Dependence in the Deformation Response of Polymer Matrix Composites Modeled

NASA Technical Reports Server (NTRS)

Goldberg, Robert K.

2000-01-01

There has been no accurate procedure for modeling the high-speed impact of composite materials, but such an analytical capability will be required in designing reliable lightweight engine-containment systems. The majority of the models in use assume a linear elastic material response that does not vary with strain rate. However, for containment systems, polymer matrix composites incorporating ductile polymers are likely to be used. For such a material, the deformation response is likely to be nonlinear and to vary with strain rate. An analytical model has been developed at the NASA Glenn Research Center at Lewis Field that incorporates both of these features. A set of constitutive equations that was originally developed to analyze the viscoplastic deformation of metals (Ramaswamy-Stouffer equations) was modified to simulate the nonlinear, rate-dependent deformation of polymers. Specifically, the effects of hydrostatic stresses on the inelastic response, which can be significant in polymers, were accounted for by a modification of the definition of the effective stress. The constitutive equations were then incorporated into a composite micromechanics model based on the mechanics of materials theory. This theory predicts the deformation response of a composite material from the properties and behavior of the individual constituents. In this manner, the nonlinear, rate-dependent deformation response of a polymer matrix composite can be predicted.

Effect of Pregabalin on Cardiovascular Responses to Exercise and Postexercise Pain and Fatigue in Fibromyalgia: A Randomized, Double-Blind, Crossover Pilot Study

PubMed Central

White, Andrea T.; Light, Kathleen C.; Bateman, Lucinda; Hughen, Ronald W.; Vanhaitsma, Timothy A.; Light, Alan R.

2015-01-01

Pregabalin, an approved treatment for fibromyalgia (FM), has been shown to decrease sympathetic nervous system (SNS) activity and inhibit sympathetically maintained pain, but its effects on exercise responses have not been reported. Methods. Using a randomized double-blind crossover design, we assessed the effect of 5 weeks of pregabalin (versus placebo) on acute cardiovascular and subjective responses to moderate exercise in 19 FM patients. Blood pressure (BP), heart rate (HR), and ratings of perceived exertion (RPE) during exercise and ratings of pain, physical fatigue, and mental fatigue before, during, and for 48 hours after exercise were compared in patients on pregabalin versus placebo and also versus 18 healthy controls. Results. On placebo, exercise RPE and BP were significantly higher in FM patients than controls (p < 0.04). Pregabalin responders (n = 12, defined by patient satisfaction and symptom changes) had significantly lower exercise BP, HR, and RPE on pregabalin versus placebo (p < 0.03) and no longer differed from controls (p > 0.26). Cardiovascular responses of nonresponders (n = 7) were not altered by pregabalin. In responders, pregabalin improved ratings of fatigue and pain (p < 0.04), but negative effects on pain and fatigue were seen in nonresponders. Conclusions. These preliminary findings suggest that pregabalin may normalize cardiovascular and subjective responses to exercise in many FM patients. PMID:27026828

Effects on response rates and costs of stamps vs business reply in a mail survey of physicians.

PubMed

Urban, N; Anderson, G L; Tseng, A

1993-05-01

In the general population, the use of stamps rather than business reply postage significantly improves response rates in mail surveys. Among physicians, however, a smaller effect might be anticipated due to their greater sophistication. An experiment was conducted to test the hypothesis that stamps would improve response rates and lower costs in a physician survey that included intensive follow up. In 1989, 380 physicians who reported providing primary care were surveyed. The protocol included two mailings, a postcard reminder, and two telephone reminders. Physicians were randomly assigned to receive a return envelope with a first-class stamp or an envelope that had been preprinted "business reply mail" in the first and second mailings. Response rates, calculated as completed surveys divided by eligible physicians, were 83.8 and 72.1% for stamps and business reply respectively, a difference of 11.7 percentage points (p < 0.01). Moreover, the total cost per completed survey was $11.18 for the physicians receiving stamps and $14.25 for the physicians receiving business reply. As in mail surveys of the general public, the use of first-class stamps on return envelopes both improves response rates and reduces cost in surveys of physicians.

An externally oriented style of thinking as a moderator of responses to affective films in women.

PubMed

Davydov, Dmitry M; Luminet, Olivier; Zech, Emmanuelle

2013-02-01

This study was conducted to test the hypothesis that differences in alexithymia would moderate coupling in physiological and subjective-experiential responses to two affective films, which were shown to induce a common negative (sad) feeling, but to provoke different hyper- or hypo-arousal physiological responses (e.g., heart rate acceleration or deceleration) associated with antipathic or empathic context, respectively (Davydov et al., 2011). Only women were studied as persons showing more reactivity to sad films than men. Reactivity was evaluated for facial behavior, physiological arousal, and subjective experience. Some other affective and cognitive disposition factors (e.g., depression and defensiveness) were considered for evaluating their probable mediation of the alexithymia's effects. While subjective experience was not affected by alexithymia, high scorers on the externally-oriented thinking factor showed reduced physiological reactivity in both film conditions. These effects were mediated through different disposition factors: either low affectivity (low depressed mood), which mediated alexithymia's effect on hyper-arousal responses (e.g., decrease of heart rate acceleration), or impression management (other-deception), which mediated alexithymia's effect on hypo-arousal responses (e.g., decrease of heart rate deceleration). Copyright © 2012 Elsevier B.V. All rights reserved.

Diverging temperature responses of CO2 assimilation and plant development explain the overall effect of temperature on biomass accumulation in wheat leaves and grains.

PubMed

Collins, Nicholas C; Parent, Boris

2017-01-09

There is a growing consensus in the literature that rising temperatures influence the rate of biomass accumulation by shortening the development of plant organs and the whole plant and by altering rates of respiration and photosynthesis. A model describing the net effects of these processes on biomass would be useful, but would need to reconcile reported differences in the effects of night and day temperature on plant productivity. In this study, the working hypothesis was that the temperature responses of CO 2 assimilation and plant development rates were divergent, and that their net effects could explain observed differences in biomass accumulation. In wheat (Triticum aestivum) plants, we followed the temperature responses of photosynthesis, respiration and leaf elongation, and confirmed that their responses diverged. We measured the amount of carbon assimilated per "unit of plant development" in each scenario and compared it to the biomass that accumulated in growing leaves and grains. Our results suggested that, up to a temperature optimum, the rate of any developmental process increased with temperature more rapidly than that of CO 2 assimilation and that this discrepancy, summarised by the CO 2 assimilation rate per unit of plant development, could explain the observed reductions in biomass accumulation in plant organs under high temperatures. The model described the effects of night and day temperature equally well, and offers a simple framework for describing the effects of temperature on plant growth. Published by Oxford University Press on behalf of the Annals of Botany Company.

Dose rate effect of pulsed electron beam on micronucleus frequency in human peripheral blood lymphocytes.

PubMed

Acharya, Santhosh; Sanjeev, Ganesh; Bhat, Nagesh N; Narayana, Yerol

2010-03-01

The micronucleus assay in human peripheral blood lymphocytes is a sensitive indicator of radiation damage and could serve as a biological dosimeter in evaluating suspected overexposure to ionising radiation. Micronucleus (MN) frequency as a measure of chromosomal damage has also extensively been employed to quantify the effects of radiation dose rate on biological systems. Here we studied the effects of 8 MeV pulsed electron beam emitted by Microtron electron accelerator on MN induction at dose rates between 35 Gy min-1 and 352.5 Gy min-1. These dose rates were achieved by varying the pulse repetition rate (PRR). Fricke dosimeter was employed to measure the absorbed dose at different PRR and to ensure uniform dose distribution of the electron beam. To study the dose rate effect, blood samples were irradiated to an absorbed dose of (4.7+/-0.2) Gy at different rates and cytogenetic damage was quantified using the micronucleus assay. The obtained MN frequency showed no dose rate dependence within the studied dose rate range. Our earlier dose effect study using 8 MeV electrons revealed that the response of MN was linear-quadratic. Therefore, in the event of an accident, dose estimation can be made using linear-quadratic dose response parameters, without adding dose rate as a correction factor.

Effects of subchronic exposures to concentrated ambient particles (CAPs) in mice. III. Acute and chronic effects of CAPs on heart rate, heart-rate fluctuation, and body temperature.

PubMed

Hwang, Jing-Shiang; Nadziejko, Christine; Chen, Lung Chi

2005-04-01

Normal mice (C57) and mice prone to develop atherosclerosis (ApoE-/-) were implanted with electrocardiograph (EKG), core body temperature, and motion transmitters were exposed daily for 6 h to Tuxedo, NY, concentrated ambient particles (CAPs) for 5 day/wk during the spring and summer of 2003. The series of 5-min EKG monitoring and body-temperature measurements were obtained for each animal in the CAPs and filtered air sham exposure groups. Our hypothesis was that chronic exposure could cause cumulative health effects. We used our recently developed nonparametric method to estimate the daily time periods that mean heart rates (HR), body temperature, and physical activity differed significantly between the CAPs and sham exposed group. CAPs exposure most affected heart rate between 1:30 a.m. and 4:30 a.m. With the response variables being the average heart rate, body temperature, and physical activity, we adopted a two-stage modeling approach to obtain the estimates of chronic and acute effects on the changes of these three response variables. In the first stage, a time-varying model estimated daily crude effects. In the second stage, the true means of the estimated crude effects were modeled with a polynominal function of time for chronic effects, a linear term of daily CAPs exposure concentrations for acute effects, and a random component for unknown noise. A Bayesian framework combined these two stages. There were significant decreasing patterns of HR, body temperature, and physical activity for the ApoE-/- mice over the 5 mo of CAPs exposure, with smaller and nonsignificant changes for the C57 mice. The chronic effect changes of the three response variables for ApoE-/- mice were maximal in the last few weeks. There was also a significant relationship between CAPs exposure concentration and short-term changes of heart rate in ApoE-/- mice during exposure. Response variables were also defined for examining fluctuations of 5-min heart rates within long (i.e., 3-6 h) and short time periods (i.e., approximately 15 min). The results for the ApoE-/- mice showed that heart-rate fluctuation within the longer periods increased to 1.35-fold by the end of exposure experiment, while the heart-rate fluctuation within 15 min decreased to 0.7-fold.

Insight into the effect of screw dislocations and oxygen vacancy defects on the optical nonlinear refraction response in chemically grown ZnO/Al2O3 films

NASA Astrophysics Data System (ADS)

Agrawal, Arpana; Saroj, Rajendra K.; Dar, Tanveer A.; Baraskar, Priyanka; Sen, Pratima; Dhar, Subhabrata

2017-11-01

We report the effect of screw dislocations and oxygen vacancy defects on the optical nonlinear refraction response of ZnO films grown on a sapphire substrate at various oxygen flow rates using the chemical vapor deposition technique. The nonlinear refraction response was investigated in the off-resonant regime using a CW He-Ne laser source to examine the role of the intermediate bandgap states. It has been observed that the structural defects strongly influence the optical nonlinearity in the off-resonant regime. Nonlinearity has been found to improve as the oxygen flow rate is lowered from 2 sccm to 0.3 sccm. From photoluminescence studies, we observe that the enhanced defect density of the electronic defect levels due to the increased concentration of structural defects (with the decrease in the oxygen flow rate) is responsible for this improved optical nonlinearity along with the thermal effect. This suggests that defect engineering is an effective way to tailor the nonlinearity of ZnO films and their utility for optoelectronic device applications.

Arginine Vasopressin Effects on Subjective Judgments and Neural Responses to Same and Other-Sex Faces in Men and Women.

PubMed

Rilling, James K; Li, Ting; Chen, Xiangchuan; Gautam, Pritam; Haroon, Ebrahim; Thompson, Richmond R

2017-01-01

Arginine vasopressin (AVP) influences social and emotional behaviors across a wide range of species. In humans, intranasal AVP has been previously shown to alter physiological responses to and subjective judgments of same-sex faces in both men and women. The present study attempted to elucidate the neural mechanism for these effects by randomizing 40 healthy men and 40 healthy women to treatment with either 40 IU intranasal AVP or a saline placebo approximately 30 min before imaging their brain function with fMRI as they viewed same and other-sex faces. All subjects were also scanned a second time several days later with no treatment to evaluate the persistence of AVP effects over time. AVP acutely increased positive ratings of same-sex faces in women, with some evidence that these effects persisted until the second scan. While AVP had no acute effects on same-sex ratings in men, AVP increased positive ratings of same-sex faces several days later. On the other hand, AVP had no effect on other-sex face judgments in either sex. AVP modulation of brain function was focused on the nucleus accumbens (NAc) and the lateral septum, two reward processing areas involved in the formation of social bonds. AVP provoked acute increases in right NAc and bilateral lateral septum responses to female faces among men, with left lateral septum responses persisting over time while right NAc responses reversed over time. Finally, AVP modulated hypothalamic activation to faces in both men and women. The present study therefore indicates that intranasal AVP affects subjective ratings and neural responses to same and other-sex faces in men and women, with some effects persisting and others emerging over time. Future studies should investigate whether AVP effects are modulated by individual variables such as genotype, personality, or attachment style as previously reported for other nonapeptides.

Systematic Review and Meta-analysis: Placebo Rates in Induction and Maintenance Trials of Ulcerative Colitis.

PubMed

Jairath, Vipul; Zou, Guangyong; Parker, Claire E; Macdonald, John K; Mosli, Mahmoud H; Khanna, Reena; Shackelton, Lisa M; Vandervoort, Margaret K; AlAmeel, Turki; Al Beshir, Mohammad; AlMadi, Majid; Al-Taweel, Talal; Atkinson, Nathan S S; Biswas, Sujata; Chapman, Thomas P; Dulai, Parambir S; Glaire, Mark A; Hoekman, Daniel; Koutsoumpas, Andreas; Minas, Elizabeth; Samaan, Mark A; Travis, Simon; D'Haens, Geert; Levesque, Barrett G; Sandborn, William J; Feagan, Brian G

2016-05-01

Minimisation of the placebo responses in randomised controlled trials [RCTs] is essential for efficient evaluation of new interventions. Placebo rates have been high in ulcerative colitis [UC] clinical trials, and factors influencing this are poorly understood. We quantify placebo response and remission rates in UC RCTs and identify trial design factors influencing them. MEDLINE, EMBASE, and the Cochrane Library were searched from inception through April 2014 for placebo-controlled trials in adult patients with UC of a biological agent, corticosteroid, immunosuppressant, or aminosalicylate. Data were independently doubly extracted. Quality was assessed using the Cochrane risk of bias tool. In all, 51 trials [48 induction and 10 maintenance phases] were identified. Placebo response and remission rates were pooled according to random-effects models, and mixed-effects meta-regression models were used to evaluate effects of study-level characteristics on these rates. Pooled estimates of placebo remission and response rates for induction trials were 10% (95% confidence interval [CI] 7-13%) and 33% [95% CI 29-37%], respectively. Corresponding values for maintenance trials were 19% [95% CI 11-30%] and 22% [95% CI 17-28%]. Trials enrolling patients with more active disease confirmed by endoscopy [endoscopy subscore ≥ 2] were associated with lower placebo rates. Conversely, placebo rates increased with increasing trial duration and number of study visits. Objective assessment of greater disease activity at trial entry by endoscopy lowered placebo rates, whereas increasing trial duration and more interactions with healthcare providers increased placebo rates. These findings have important implications for design and conduct of clinical trials. Copyright © 2016 European Crohn’s and Colitis Organisation (ECCO). Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Summary of the effects of engine throttle response on airplane formation-flying qualities

NASA Technical Reports Server (NTRS)

Walsh, Kevin R.

1993-01-01

A flight evaluation was conducted to determine the effect of engine throttle response characteristics on precision formation-flying qualities. A variable electronic throttle control system was developed and flight-tested on a TF-104G airplane with a J79-11B engine at the NASA Dryden Flight Research Facility. This airplane was chosen because of its known, very favorable thrust response characteristics. Ten research flights were flown to evaluate the effects of throttle gain, time delay, and fuel control rate limiting on engine handling qualities during a demanding precision wing formation task. Handling quality effects of lag filters and lead compensation time delays were also evaluated. The Cooper and Harper Pilot Rating Scale was used to assign levels of handling quality. Data from pilot ratings and comments indicate that throttle control system time delays and rate limits cause significant degradations in handling qualities. Threshold values for satisfactory (level 1) and adequate (level 2) handling qualities of these key variables are presented. These results may provide engine manufacturers with guidelines to assure satisfactory handling qualities in future engine designs.

Temperature-dependent body size effects determine population responses to climate warming.

PubMed

Lindmark, Max; Huss, Magnus; Ohlberger, Jan; Gårdmark, Anna

2018-02-01

Current understanding of animal population responses to rising temperatures is based on the assumption that biological rates such as metabolism, which governs fundamental ecological processes, scale independently with body size and temperature, despite empirical evidence for interactive effects. Here, we investigate the consequences of interactive temperature- and size scaling of vital rates for the dynamics of populations experiencing warming using a stage-structured consumer-resource model. We show that interactive scaling alters population and stage-specific responses to rising temperatures, such that warming can induce shifts in population regulation and stage-structure, influence community structure and govern population responses to mortality. Analysing experimental data for 20 fish species, we found size-temperature interactions in intraspecific scaling of metabolic rate to be common. Given the evidence for size-temperature interactions and the ubiquity of size structure in animal populations, we argue that accounting for size-specific temperature effects is pivotal for understanding how warming affects animal populations and communities. © 2017 The Authors. Ecology Letters published by CNRS and John Wiley & Sons Ltd.

Reinforcing effects of sigma-receptor agonists in rats trained to self-administer cocaine.

PubMed

Hiranita, Takato; Soto, Paul L; Tanda, Gianluigi; Katz, Jonathan L

2010-02-01

sigma-Receptor (sigmaR) antagonists have been reported to block certain effects of psychostimulant drugs. The present study examined the effects of sigmaR ligands in rats trained to self-administer cocaine (0.032-1.0 mg/kg/inj i.v.) under fixed-ratio 5-response schedules of reinforcement. Maximal rates of responding were maintained by 0.32 mg/kg/inj cocaine, or by the sigmaR agonists, 1,3-di-(2-tolyl)guanidine (DTG; 1.0 mg/kg/inj) or 2-(4-morpholinethyl) 1-phenylcyclohexane-1-carboxylate hydrochloride (PRE-084; 0.32 mg/kg/inj), when substituted for cocaine. Lower response rates were maintained at higher and lower doses of the compounds. No dose of the sigmaR antagonists [N-[2-(3,4-dichlorophenyl)ethyl]-N-methyl-2-(1-pyrrolidinyl)ethylamine (BD 1008), N-[2-(3,4-dichlorophenyl)ethyl]-N-methyl-2-(dimethylamino)ethylamine (BD 1047), N-[2-(3,4-dichlorophenyl)ethyl]-4-methylpiperazine (BD 1063)] maintained responding appreciably above levels obtained when responding had no consequences. Presession treatment with sigmaR agonists dose-dependently shifted the cocaine self-administration dose-effect curve leftward. The dopamine-uptake inhibitor, (-)-2beta-carbomethoxy-3beta-(4-fluorophenyl)tropane (WIN 35,428), dose-dependently shifted the DTG and PRE-084 self-administration dose-effect curves leftward. Treatment with the sigmaR antagonists dose-dependently decreased response rates maintained by DTG or PRE-084, but did not affect cocaine self-administration. Response rates maintained by maximally effective DTG or PRE-084 doses were decreased by sigmaR antagonists at lower doses than those that decreased response rates maintained by food reinforcement. Although sigmaR antagonists block some cocaine-induced effects, the lack of effect on cocaine self-administration suggests that the primary reinforcing effects of cocaine do not involve direct effects at sigmaRs. However, the self-administration of sigmaR agonists in cocaine-trained subjects, facilitation of cocaine self-administration by sigmaR-agonist pretreatment, and the facilitation of sigmaR-agonist self-administration by WIN 35,428, together suggest enhanced abuse-related effects resulting from concomitant dopaminergically mediated actions and sigmaR-mediated actions of the drugs.

Reinforcing Effects of σ-Receptor Agonists in Rats Trained to Self-Administer Cocaine

PubMed Central

Hiranita, Takato; Soto, Paul L.; Tanda, Gianluigi

2010-01-01

σ-Receptor (σR) antagonists have been reported to block certain effects of psychostimulant drugs. The present study examined the effects of σR ligands in rats trained to self-administer cocaine (0.032–1.0 mg/kg/inj i.v.) under fixed-ratio 5-response schedules of reinforcement. Maximal rates of responding were maintained by 0.32 mg/kg/inj cocaine, or by the σR agonists, 1,3-di-(2-tolyl)guanidine (DTG; 1.0 mg/kg/inj) or 2-(4-morpholinethyl) 1-phenylcyclohexane-1-carboxylate hydrochloride (PRE-084; 0.32 mg/kg/inj), when substituted for cocaine. Lower response rates were maintained at higher and lower doses of the compounds. No dose of the σR antagonists [N-[2-(3,4-dichlorophenyl)ethyl]-N-methyl-2-(1-pyrrolidinyl)ethylamine (BD 1008), N-[2-(3,4-dichlorophenyl)ethyl]-N-methyl-2-(dimethylamino)ethylamine (BD 1047), N-[2-(3,4-dichlorophenyl)ethyl]-4-methylpiperazine (BD 1063)] maintained responding appreciably above levels obtained when responding had no consequences. Presession treatment with σR agonists dose-dependently shifted the cocaine self-administration dose-effect curve leftward. The dopamine-uptake inhibitor, (−)-2β-carbomethoxy-3β-(4-fluorophenyl)tropane (WIN 35,428), dose-dependently shifted the DTG and PRE-084 self-administration dose-effect curves leftward. Treatment with the σR antagonists dose-dependently decreased response rates maintained by DTG or PRE-084, but did not affect cocaine self-administration. Response rates maintained by maximally effective DTG or PRE-084 doses were decreased by σR antagonists at lower doses than those that decreased response rates maintained by food reinforcement. Although σR antagonists block some cocaine-induced effects, the lack of effect on cocaine self-administration suggests that the primary reinforcing effects of cocaine do not involve direct effects at σRs. However, the self-administration of σR agonists in cocaine-trained subjects, facilitation of cocaine self-administration by σR-agonist pretreatment, and the facilitation of σR-agonist self-administration by WIN 35,428, together suggest enhanced abuse-related effects resulting from concomitant dopaminergically mediated actions and σR-mediated actions of the drugs. PMID:19892920

Meta-Analysis of the Antidepressant Effects of Acute Sleep Deprivation.

PubMed

Boland, Elaine M; Rao, Hengyi; Dinges, David F; Smith, Rachel V; Goel, Namni; Detre, John A; Basner, Mathias; Sheline, Yvette I; Thase, Michael E; Gehrman, Philip R

To provide a quantitative meta-analysis of the antidepressant effects of sleep deprivation to complement qualitative reviews addressing response rates. English-language studies from 1974 to 2016 using the keywords sleep deprivation and depression searched through PubMed and PsycINFO databases. A total of 66 independent studies met criteria for inclusion: conducted experimental sleep deprivation, reported the percentage of the sample that responded to sleep deprivation, provided a priori definition of antidepressant response, and did not seamlessly combine sleep deprivation with other therapies (eg, chronotherapeutics, repetitive transcranial magnetic stimulation). Data extracted included percentage of responders, type of sample (eg, bipolar, unipolar), type of sleep deprivation (eg, total, partial), demographics, medication use, type of outcome measure used, and definition of response (eg, 30% reduction in depression ratings). Data were analyzed with meta-analysis of proportions and a Poisson mixed-effects regression model. The overall response rate to sleep deprivation was 45% among studies that utilized a randomized control group and 50% among studies that did not. The response to sleep deprivation was not affected significantly by the type of sleep deprivation performed, the nature of the clinical sample, medication status, the definition of response used, or age and gender of the sample. These findings support a significant effect of sleep deprivation and suggest the need for future studies on the phenotypic nature of the antidepressant response to sleep deprivation, on the neurobiological mechanisms of action, and on moderators of the sleep deprivation treatment response in depression. © Copyright 2017 Physicians Postgraduate Press, Inc.

Atomoxetine Increased Effect over Time in Adults with Attention-Deficit/Hyperactivity Disorder Treated for up to 6 Months: Pooled Analysis of Two Double-Blind, Placebo-Controlled, Randomized Trials.

PubMed

Wietecha, Linda A; Clemow, David B; Buchanan, Andrew S; Young, Joel L; Sarkis, Elias H; Findling, Robert L

2016-07-01

Changes in the magnitude of efficacy throughout 26 weeks of atomoxetine treatment, along with impact of dosing, were evaluated in adults with ADHD from two randomized, double-blind, placebo-controlled studies. Pooled placebo (n = 485) and atomoxetine (n = 518) patients, dosed 25, 40, 60, 80 (target dose), or 100 mg daily, were assessed. Change from baseline in Conners' Adult ADHD Rating Scale-Investigator Rated Scale: Screening Version (CAARS) total ADHD symptoms score and Adult ADHD Investigator Symptom Rating Scale (AISRS) total score were analyzed using mixed-model repeated measures, with least squares mean change, effect size, and response rate calculated at 1, 2, 4, 8, 12, 16, 22, and 26 weeks. Decreases on CAARS for atomoxetine- versus placebo-treated patients were consistently statistically significantly greater at every time point beginning at one week (P ≤ 0.006, 0.28 effect size). By 4 weeks, comparison was -13.19 compared with -8.84 (P < 0.0001, 0.45 effect size). By 26 weeks, mean change was -15.42 versus -9.71 (0.52 effect size); increase in effect size over time was most pronounced in the 80 mg group (0.82 effect size). AISRS demonstrated similar results. Atomoxetine response rate (CAARS 50% decrease) continued to increase throughout 26 weeks. Atomoxetine treatment in adults with ADHD was associated with small effect sizes after 4 weeks and moderate effect sizes by 6 months of treatment. The data support increased effect size and response rate over time during longer-term treatment at target dose. © 2016 Eli Lilly and Company. CNS Neuroscience & Therapeutics published by John Wiley & Sons Ltd.

Effect of Processing Parameters on the Physical, Thermal, and Combustion Properties of Plasma-Synthesized Aluminum Nanopowders

DTIC Science & Technology

2011-02-01

only a couple of processing parameters. Table 2 Statistical results of the DOE Run no. Plasma power Feed rate System pressure Quench rate...and quench rate. Particle size was chosen as the measured response due to its predominant effect on material properties. The results of the DOE...showed that feed rate and quench rate have the largest effect on particle size. All synthesized powders were characterized by thermogravimetric

Laser-based irradiation apparatus and method to measure the functional dose-rate response of semiconductor devices

DOEpatents

Horn, Kevin M [Albuquerque, NM

2008-05-20

A broad-beam laser irradiation apparatus can measure the parametric or functional response of a semiconductor device to exposure to dose-rate equivalent infrared laser light. Comparisons of dose-rate response from before, during, and after accelerated aging of a device, or from periodic sampling of devices from fielded operational systems can determine if aging has affected the device's overall functionality. The dependence of these changes on equivalent dose-rate pulse intensity and/or duration can be measured with the apparatus. The synchronized introduction of external electrical transients into the device under test can be used to simulate the electrical effects of the surrounding circuitry's response to a radiation exposure while exposing the device to dose-rate equivalent infrared laser light.

Probability Distribution of Dose and Dose-Rate Effectiveness Factor for use in Estimating Risks of Solid Cancers From Exposure to Low-Let Radiation.

PubMed

Kocher, David C; Apostoaei, A Iulian; Hoffman, F Owen; Trabalka, John R

2018-06-01

This paper presents an analysis to develop a subjective state-of-knowledge probability distribution of a dose and dose-rate effectiveness factor for use in estimating risks of solid cancers from exposure to low linear energy transfer radiation (photons or electrons) whenever linear dose responses from acute and chronic exposure are assumed. A dose and dose-rate effectiveness factor represents an assumption that the risk of a solid cancer per Gy at low acute doses or low dose rates of low linear energy transfer radiation, RL, differs from the risk per Gy at higher acute doses, RH; RL is estimated as RH divided by a dose and dose-rate effectiveness factor, where RH is estimated from analyses of dose responses in Japanese atomic-bomb survivors. A probability distribution to represent uncertainty in a dose and dose-rate effectiveness factor for solid cancers was developed from analyses of epidemiologic data on risks of incidence or mortality from all solid cancers as a group or all cancers excluding leukemias, including (1) analyses of possible nonlinearities in dose responses in atomic-bomb survivors, which give estimates of a low-dose effectiveness factor, and (2) comparisons of risks in radiation workers or members of the public from chronic exposure to low linear energy transfer radiation at low dose rates with risks in atomic-bomb survivors, which give estimates of a dose-rate effectiveness factor. Probability distributions of uncertain low-dose effectiveness factors and dose-rate effectiveness factors for solid cancer incidence and mortality were combined using assumptions about the relative weight that should be assigned to each estimate to represent its relevance to estimation of a dose and dose-rate effectiveness factor. The probability distribution of a dose and dose-rate effectiveness factor for solid cancers developed in this study has a median (50th percentile) and 90% subjective confidence interval of 1.3 (0.47, 3.6). The harmonic mean is 1.1, which implies that the arithmetic mean of an uncertain estimate of the risk of a solid cancer per Gy at low acute doses or low dose rates of low linear energy transfer radiation is only about 10% less than the mean risk per Gy at higher acute doses. Data were also evaluated to define a low acute dose or low dose rate of low linear energy transfer radiation, i.e., a dose or dose rate below which a dose and dose-rate effectiveness factor should be applied in estimating risks of solid cancers.

Induction Speed Is Not a Determinant of Propofol Pharmacodynamics

PubMed Central

Doufas, Anthony G.; Bakhshandeh, Maryam; Bjorksten, Andrew R.; Shafer, Steven L.; Sessler, Daniel I.

2005-01-01

Summary We used individual pharmacodynamic modeling to demonstrate that different sedation endpoints occur at the same effect site propofol concentration, independent of the infusion rate of propofol. Background Evidence suggests that the rate at which they are infused may influence plasma-effect site equilibration of intravenous anesthetics. We used 5 different rates of propofol administration to test the hypothesis that different sedation endpoints occur at the same effect site propofol concentration, independent of the infusion rate. We concurrently evaluated the automated responsiveness monitor (ARM) against other sedation measures and the propofol effect site concentration. Methods With Human Studies Committee approval, 18 healthy volunteers received 5 consecutive target-controlled propofol infusions. During each infusion the effect site concentration was increased by a rate of 0.1, 0.3, 0.5, 0.7, or 0.9 μg·ml−1·min−1. Bispectral index and ARM were recorded at frequent intervals. The times of syringe drop and loss and recovery of responsiveness were noted. Pharmacokinetic and pharmacodynamic modeling was performed using NONMEM. Results Once the correct rate of plasma-effect site equilibration (ke0) was determined for each individual (ke0 = 0.17 min−1, time-to-peak effect = 2.7 min), the effect site concentrations associated with each clinical measure were not affected by the rate of rise of effect site propofol concentration. ARM correlated with all clinical measures of drug effect. Subjects invariably stopped responding to ARM at lower effect site propofol concentrations than those associated with loss of responsiveness. Conclusions Population-based pharmacokinetics, combined with real-time electroencephalographic measures of drug effect, may provide a means to individualize pharmacodynamic modeling during target-controlled drug delivery. ARM appears useful as an automated measure of sedation and may provide the basis for automated monitoring and titration of sedation for a propofol delivery system. PMID:15505446

Effect of dark pretreatment on the kinetics of response of barley pulvini to gravistimulation and hormones

NASA Technical Reports Server (NTRS)

Brock, T. G.; Kaufman, P. B.

1988-01-01

Starch in pulvinus amyloplasts of barley (Hordeum vulgare cv Larker) disappears when 45-day-old, light-grown plants are given 5 days of continuous darkness. The effect of this loss on the pulvinus graviresponse was evaluated by following changes in the kinetics of response during the 5-day dark period. Over 5 days of dark pretreatment, the lag to initial graviresponse and the subsequent half-time to maximum steady state bending rate increased significantly while the maximum bending rate did not change. The change in response to applied indoleacetic acid (100 micromolar) plus gibberellic acid (10 micromolar) without gravistimulation, under identical dark pretreatments, was used as a model system for the response component of gravitropism. Dark pretreatment did not change the lag to initial response following hormone application to vertical pulvini, but both the maximum bending rate and the half-time to the maximum rate were significantly reduced. Also, after dark pretreatment, significant bending responses following hormone application were observed in vertical segments with or without added sucrose, while gravistimulation produced a response only if segments were given sucrose. These results indicate that starch-filled amyloplasts are required for the graviresponse of barley pulvini and suggest that they function in the stimulus perception and signal transduction components of gravitropism.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sinsabaugh, Robert L.; Belnap, Jayne; Rudgers, Jennifer

The N cycle of arid ecosystems is influenced by low soil organic matter, high soil pH, and extremes in water potential and temperature that lead to open canopies and development of biological soil crusts (biocrusts). We investigated the effects of N amendment on soil microbial dynamics in a Larrea tridentata-Ambrosia dumosa shrubland site in southern Nevada USA. Sites were fertilized with a NO 3-NH 4 mix at 0, 7, and 15 kg N ha -1 y -1 from March 2012 to March 2013. In March 2013, biocrust (0–0.5 cm) and bulk soils (0–10 cm) were collected beneath Ambrosia canopies andmore » in the interspaces between plants. Biomass responses were assessed as bacterial and fungal SSU rRNA gene copy number and chlorophyll a concentration. Metabolic responses were measured by five ecoenzyme activities and rates of N transformation. By most measures, nutrient availability, microbial biomass, and process rates were greater in soils beneath the shrub canopy compared to the interspace between plants, and greater in the surface biocrust horizon compared to the deeper 10 cm soil profile. Most measures responded positively to experimental N addition. Effect sizes were generally greater for bulk soil than biocrust. Results were incorporated into a meta-analysis of arid ecosystem responses to N amendment that included data from 14 other studies. Effect sizes were calculated for biomass and metabolic responses. Regressions of effect sizes, calculated for biomass, and metabolic responses, showed similar trends in relation to N application rate and N load (rate × duration). The critical points separating positive from negative treatment effects were 88 kg ha -1 y -1 and 159 kg ha -1, respectively, for biomass, and 70 kg ha -1 y -1 and 114 kg ha -1, respectively, for metabolism. These critical values are comparable to those for microbial biomass, decomposition rates and respiration reported in broader meta-analyses of N amendment effects in mesic ecosystems. As a result, large effect sizes at low N addition rates indicate that arid ecosystems are sensitive to modest increments in anthropogenic N deposition.« less

Pre-Survey Text Messages (SMS) Improve Participation Rate in an Australian Mobile Telephone Survey: An Experimental Study.

PubMed

Dal Grande, Eleonora; Chittleborough, Catherine Ruth; Campostrini, Stefano; Dollard, Maureen; Taylor, Anne Winifred

2016-01-01

Mobile telephone numbers are increasingly being included in household surveys samples. As approach letters cannot be sent because many do not have address details, alternatives approaches have been considered. This study assesses the effectiveness of sending a short message service (SMS) to a random sample of mobile telephone numbers to increase response rates. A simple random sample of 9000 Australian mobile telephone numbers: 4500 were randomly assigned to be sent a pre-notification SMS, and the remaining 4500 did not have a SMS sent. Adults aged 18 years and over, and currently in paid employment, were eligible to participate. American Association for Public Opinion Research formulas were used to calculated response cooperation and refusal rates. Response and cooperation rate were higher for the SMS groups (12.4% and 28.6% respectively) than the group with no SMS (7.7% and 16.0%). Refusal rates were lower for the SMS group (27.3%) than the group with no SMS (35.9%). When asked, 85.8% of the pre-notification group indicated they remembered receiving a SMS about the study. Sending a pre-notification SMS is effective in improving participation in population-based surveys. Response rates were increased by 60% and cooperation rates by 79%.

The effect of heat transfer mode on heart rate responses and hysteresis during heating and cooling in the estuarine crocodile Crocodylus porosus.

PubMed

Franklin, Craig E; Seebacher, Frank

2003-04-01

The effect of heating and cooling on heart rate in the estuarine crocodile Crocodylus porosus was studied in response to different heat transfer mechanisms and heat loads. Three heating treatments were investigated. C. porosus were: (1) exposed to a radiant heat source under dry conditions; (2) heated via radiant energy while half-submerged in flowing water at 23 degrees C and (3) heated via convective transfer by increasing water temperature from 23 degrees C to 35 degrees C. Cooling was achieved in all treatments by removing the heat source and with C. porosus half-submerged in flowing water at 23 degrees C. In all treatments, the heart rate of C. porosus increased markedly in response to heating and decreased rapidly with the removal of the heat source. Heart rate during heating was significantly faster than during cooling at any given body temperature, i.e. there was a significant heart rate hysteresis. There were two identifiable responses to heating and cooling. During the initial stages of applying or removing the heat source, there was a dramatic increase or decrease in heart rate ('rapid response'), respectively, indicating a possible cardiac reflex. This rapid change in heart rate with only a small change or no change in body temperature (<0.5 degrees C) resulted in Q(10) values greater than 4000, calling into question the usefulness of this measure on heart rate during the initial stages of heating and cooling. In the later phases of heating and cooling, heart rate changed with body temperature, with Q(10) values of 2-3. The magnitude of the heart rate response differed between treatments, with radiant heating during submergence eliciting the smallest response. The heart rate of C. porosus outside of the 'rapid response' periods was found to be a function of the heat load experienced at the animal surface, as well as on the mode of heat transfer. Heart rate increased or decreased rapidly when C. porosus experienced large positive (above 25 W) or negative (below -15 W) heat loads, respectively, in all treatments. For heat loads between -15 W and 20 W, the increase in heart rate was smaller for the 'unnatural' heating by convection in water compared with either treatment using radiant heating. Our data indicate that changes in heart rate constitute a thermoregulatory mechanism that is modulated in response to the thermal environment occupied by the animal, but that heart rate during heating and cooling is, in part, controlled independently of body temperature.

Effects of various methodologic strategies: survey response rates among Canadian physicians and physicians-in-training.

PubMed

Grava-Gubins, Inese; Scott, Sarah

2008-10-01

To increase the overall 2007 response rate of the National Physician Survey (NPS) from the survey's 2004 rate of response with the implementation of various methodologic strategies. Physicians were stratified to receive either a long version (12 pages) or a short version (6 pages) of the survey (38% and 62%, respectively). Mixed modes of contact were used-58% were contacted by e-mail and 42% by regular mail-with multiple modes of contact attempted for nonrespondents. The self-administered, confidential surveys were distributed in either English or French. Medical residents and students received e-mail surveys only and were offered a substantial monetary lottery incentive for completing their surveys. A professional communications firm assisted in marketing the survey and delivered advance notification of its impending distribution. Canada. A total of 62 441 practising physicians, 2627 second-year medical residents, and 9162 medical students in Canada. Of the practising physicians group, 60 811 participants were eligible and 19 239 replied, for an overall 2007 study response rate of 31.64% (compared with 35.85% in 2004). No difference in rate of response was found between the longer and shorter versions of the survey. If contacted by regular mail, the response rate was 34.1%; the e-mail group had a response rate of 29.9%. Medical student and resident response rates were 30.8% and 27.9%, respectively (compared with 31.2% and 35.6% in 2004). Despite shortening the questionnaires, contacting more physicians by e-mail, and enhancing marketing and follow-up, the 2007 NPS response rate for practising physicians did not surpass the 2004 NPS response rate. Offering a monetary lottery incentive to medical residents and students was also unsuccessful in increasing their response rates. The role of surveys in gathering information from physicians and physicians-in-training remains problematic. Researchers need to investigate alternative strategies for achieving higher rates of response.

Predictions of psychophysical measurements for sinusoidal amplitude modulated (SAM) pulse-train stimuli from a stochastic model.

PubMed

Xu, Yifang; Collins, Leslie M

2007-08-01

Two approaches have been proposed to reduce the synchrony of the neural response to electrical stimuli in cochlear implants. One approach involves adding noise to the pulse-train stimulus, and the other is based on using a high-rate pulse-train carrier. Hypotheses regarding the efficacy of the two approaches can be tested using computational models of neural responsiveness prior to time-intensive psychophysical studies. In our previous work, we have used such models to examine the effects of noise on several psychophysical measures important to speech recognition. However, to date there has been no parallel analytic solution investigating the neural response to the high-rate pulse-train stimuli and their effect on psychophysical measures. This work investigates the properties of the neural response to high-rate pulse-train stimuli with amplitude modulated envelopes using a stochastic auditory nerve model. The statistics governing the neural response to each pulse are derived using a recursive method. The agreement between the theoretical predictions and model simulations is demonstrated for sinusoidal amplitude modulated (SAM) high rate pulse-train stimuli. With our approach, predicting the neural response in modern implant devices becomes tractable. Psychophysical measurements are also predicted using the stochastic auditory nerve model for SAM high-rate pulse-train stimuli. Changes in dynamic range (DR) and intensity discrimination are compared with that observed for noise-modulated pulse-train stimuli. Modulation frequency discrimination is also studied as a function of stimulus level and pulse rate. Results suggest that high rate carriers may positively impact such psychophysical measures.

Coping with thermal challenges: physiological adaptations to environmental temperatures.

PubMed

Tattersall, Glenn J; Sinclair, Brent J; Withers, Philip C; Fields, Peter A; Seebacher, Frank; Cooper, Christine E; Maloney, Shane K

2012-07-01

Temperature profoundly influences physiological responses in animals, primarily due to the effects on biochemical reaction rates. Since physiological responses are often exemplified by their rate dependency (e.g., rate of blood flow, rate of metabolism, rate of heat production, and rate of ion pumping), the study of temperature adaptations has a long history in comparative and evolutionary physiology. Animals may either defend a fairly constant temperature by recruiting biochemical mechanisms of heat production and utilizing physiological responses geared toward modifying heat loss and heat gain from the environment, or utilize biochemical modifications to allow for physiological adjustments to temperature. Biochemical adaptations to temperature involve alterations in protein structure that compromise the effects of increased temperatures on improving catalytic enzyme function with the detrimental influences of higher temperature on protein stability. Temperature has acted to shape the responses of animal proteins in manners that generally preserve turnover rates at animals' normal, or optimal, body temperatures. Physiological responses to cold and warmth differ depending on whether animals maintain elevated body temperatures (endothermic) or exhibit minimal internal heat production (ectothermic). In both cases, however, these mechanisms involve regulated neural and hormonal over heat flow to the body or heat flow within the body. Examples of biochemical responses to temperature in endotherms involve metabolic uncoupling mechanisms that decrease metabolic efficiency with the outcome of producing heat, whereas ectothermic adaptations to temperature are best exemplified by the numerous mechanisms that allow for the tolerance or avoidance of ice crystal formation at temperatures below 0°C. 2012 American Physiological Society. Compr Physiol 2:2037-2061, 2012.

Isolated Limb Perfusion for Malignant Melanoma: Systematic Review on Effectiveness and Safety

PubMed Central

de la Cruz-Merino, Luis; Ferrandiz, Lara; Villegas-Portero, Roman; Nieto-Garcia, Adoracion

2010-01-01

Background. Isolated limb perfusion (ILP) involves the administration of chemotherapy drugs directly into a limb involved by locoregional metastases. Unresectable locally advanced melanoma of the limbs represents one of the clinical settings in which ILP has demonstrated benefits. Methods. A systematic review of the literature on ILP for patients with unresectable locally advanced melanoma of the limbs was conducted. MEDLINE, EMBASE, and Cochrane database searches were conducted to identify studies fulfilling the following inclusion criteria: hyper- or normothermic ILP with melphalan with or without tumor necrosis factor (TNF) or other drugs providing valid data on clinical response, survival, or toxicity. To allocate levels of evidence and grades of recommendation the Scottish Intercollegiate Guidelines Network system was used. Results. Twenty-two studies including 2,018 ILPs were selected with a clear predominance of observational studies (90.90%) against experimental studies (9.10%). The median complete response rate to ILP was of 58.20%, with a median overall response rate of 90.35%. ILP with melphalan yielded a median complete response rate of 46.50%, against a 68.90% median complete response rate for melphalan plus TNF ILP. The median 5-year overall-survival rate was 36.50%, with a median overall survival interval of 36.70 months. The Wieberdink IV and V regional toxicity rates were 2.00% and 0.65%, respectively. Conclusions. ILP is effective in achieving clinical responses in patients with unresectable locally advanced melanoma of the limbs. The disease-free and overall survival rates provided by ILP are acceptable. ILP is safe, with a low incidence of severe regional and systemic toxicity. PMID:20348274

Effect of skin wettedness on sweat gland response

NASA Technical Reports Server (NTRS)

Nadel, E. R.; Stolwijk, J. A. J.

1973-01-01

Investigation of the effect of skin wettedness upon sweating rate. Several techniques were used to gain a better understanding of the quantitative nature of this effect. The results include the finding that the evaporative power of the environment has a profound effect on the relationship between body temperature and sweating rate.

Comparative treatment effectiveness of direct acting antiviral regimens for hepatitis C: Data from the Veterans administration.

PubMed

Fox, D Steven; McGinnis, Justin J; Tonnu-Mihara, Ivy Q; McCombs, Jeffrey S

2017-06-01

Data addressing real world effectiveness of direct acting antiviral agents in hepatitis C infected patients are now emerging. This study compared the sustained virologic response rates achieved 12 weeks post-treatment in patients treated with three such agents by the Veterans Health Administration. A retrospective cohort study was conducted using patients who terminated treatment by July 1, 2015. Data were retrieved from the Veterans Health Administration electronic medical records system. Patients were included if sufficient viral load laboratory data were available to determine sustained virologic response. Applying an intention to treat approach and logistic regression analysis, the sustained virologic response rates achieved were compared across drug regimens. A total of 11 464 patients met study selection criteria. Without controlling for other risk factors, sustained virologic response at least 12 weeks post treatment was achieved in 92% of ledipasvir/ sofosbuvir, 86% of ombitasvir/paritaprevir/ritonavir/dasabuvir, and 83% of simeprevir/sofosbuvir patients. After adjusting for patient characteristics, simeprevir/sofosbuvir (93.3%) and ledipasvir/sofosbuvir (96.2%) patients were statistically more likely than ombitasvir/paritaprevir/ritonavir/dasabuvir (91.8%) patients to demonstrate sustained virologic response. Human immunodeficiency virus, hepatitis B infection, diabetes, obesity, previous treatment history and augmentation therapy using ribavirin did not impact sustained virologic response rates. Sustained virologic response rates were lower for patients under age 65, with cirrhosis, decompensated cirrhosis, hepatocellular carcinoma, indications of fibrosis, or a non-genotype 1 infection. Women and Caucasian patients were more likely to achieve a sustained virologic response. All three direct acting antiviral regimens appear highly effective in achieving sustained virologic response. © 2016 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

Endogenous angiotensin affects responses to stimulation of baroreceptor afferent nerves.

PubMed

DiBona, Gerald F; Jones, Susan Y

2003-08-01

To study effects of endogenous angiotensin II on responses to standardized stimulation of afferent neural input into the central portion of the arterial and cardiac baroreflexes. Different dietary sodium intakes were used to physiologically alter endogenous angiotensin II activity. Candesartan, an angiotensin II type 1 receptor antagonist, was used to assess dependency of observed effects on angiotensin II stimulation of angiotensin II type 1 receptors. Electrical stimulation of arterial and cardiac baroreflex afferent nerves was used to provide a standardized input to the central portion of the arterial and cardiac baroreflexes. In anesthetized rats in balance on low, normal and high dietary sodium intake, arterial pressure, heart rate and renal sympathetic nerve activity responses to electrical stimulation of vagus and aortic depressor nerves were determined. Compared with plasma renin activity values in normal dietary sodium intake rats, those from low dietary sodium intake rats were higher and those from high dietary sodium intake rats were lower. During vagus nerve stimulation, the heart rate, arterial pressure and renal sympathetic nerve activity responses were similar in all three dietary sodium intake groups. During aortic depressor nerve stimulation, the heart rate and arterial pressure responses were similar in all three dietary sodium intake groups. However, the renal sympathetic nerve activity response was significantly greater in the low sodium group than in the normal and high sodium group at 4, 8 and 16 Hz. Candesartan administered to low dietary sodium intake rats had no effect on the heart rate and arterial pressure responses to either vagus or aortic depressor nerve stimulation but increased the magnitude of the renal sympathoinhibitory responses. Increased endogenous angiotensin II in rats on a low dietary sodium intake attenuates the renal sympathoinhibitory response to activation of the cardiac and sinoaortic baroreflexes by standardized vagus and aortic depressor nerve stimulation, respectively.

Occasional Reinforced Responses during Extinction Can Slow the Rate of Reacquisition of an Operant Response

ERIC Educational Resources Information Center

Woods, Amanda M.; Bouton, Mark E.

2007-01-01

Three experiments with rats examined reacquisition of an operant response after either extinction or a response-elimination procedure that included occasional reinforced responses during extinction. In each experiment, reacquisition was slower when response elimination had included occasional reinforced responses, although the effect was…

Evaluating CollaboRATE in a clinical setting: analysis of mode effects on scores, response rates and costs of data collection.

PubMed

Barr, Paul J; Forcino, Rachel C; Thompson, Rachel; Ozanne, Elissa M; Arend, Roger; Castaldo, Molly Ganger; O'Malley, A James; Elwyn, Glyn

2017-03-24

Shared decision-making (SDM) has become a policy priority, yet its implementation is not routinely assessed. To address this gap we tested the delivery of CollaboRATE, a 3-item patient reported experience measure of SDM, via multiple survey modes. To assess CollaboRATE response rates and respondent characteristics across different modes of administration, impact of mode and patient characteristics on SDM performance and cost of administration per response in a real-world primary care practice. Observational study design, with repeated assessment of SDM performance using CollaboRATE in a primary care clinic over 15 months of data collection. Different modes of administration were introduced sequentially including paper, patient portal, interactive voice response (IVR) call, text message and tablet computer. Consecutive patients ≥18 years, or parents/guardians of patients <18 years, visiting participating primary care clinicians. CollaboRATE assesses three core SDM tasks: (1) explanation about health issues, (2) elicitation of patient preferences and (3) integration of patient preferences into decisions. Responses to each item range from 0 (no effort was made) to 9 (every effort was made). CollaboRATE scores are calculated as the proportion of participants who report a score of nine on each of the three CollaboRATE questions. Scores were sensitive to mode effects: the paper mode had the highest average score (81%) and IVR had the lowest (61%). However, relative clinician performance rankings were stable across the different data collection modes used. Tablet computers administered by research staff had the highest response rate (41%), although this approach was costly. Clinic staff giving paper surveys to patients as they left the clinic had the lowest response rate (12%). CollaboRATE can be introduced using multiple modes of survey delivery while producing consistent clinician rankings. This may allow routine assessment and benchmarking of clinician and clinic SDM performance. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Effects of physiological and/or disease status on the response of postpartum dairy cows to synchronization of estrus using an intravaginal progesterone device.

PubMed

McNally, Julie C; Crowe, Mark A; Roche, James F; Beltman, Marijke E

2014-12-01

Progesterone treatments are used to increase submission rates in postpartum dairy cows; however, in many cases the protocol is used as a blanket therapy for all cows without regard for physiological or disease state. The objective of this study was to identify the physiological or disease classes of cows that respond well (or not) to synchronization of estrus via progesterone. Dairy cows (n = 402) were monitored peri and postpartum to establish their physiological or disease status. Animals were classified as having negative energy balance, clinical lameness, uterine infection (UI), anovulatory anestrus, high somatic cell counts, and healthy (H). Blood samples were collected at five different time points and analyzed for metabolites. All animals received an 8-day controlled internal drug release protocol, which included GnRH at insertion and PGF2α the day before removal. Response to the protocol was determined by visual observation of estrus synchronization. Conception rate was determined by ultrasonography between Days 32 and 35 after artificial insemination. Animals without UI were 1.9 times more likely to respond and two times more likely to be confirmed pregnant than those with UI. There was no relationship between negative energy balance and clinical lameness in the visual estrous response, but both conditions were associated with reduced conception rates. Dairy cows in anovulatory anestrus responded successfully to the protocol in both estrous response and conception rates. High glutathione peroxidase concentrations had a positive effect on conception rates, whereas high non-esterified fatty acids and beta-hydroxybutyrate had a negative effect on the estrous response. In conclusion, disease and physiological states of dairy cows determined the response to progesterone-based synchronization. The more disease or physiological problems the cows had, the lower the estrous response and conception rates; cows with these problems were not ideal candidates for synchronization. Both anestrus and healthy dairy cows were good responders to progesterone-based synchronization. Copyright © 2014 Elsevier Inc. All rights reserved.

Effects of opioid- and non-opioid analgesics on responses to psychosocial stress in humans.

PubMed

Bershad, Anya K; Miller, Melissa A; Norman, Greg J; de Wit, Harriet

2018-06-01

Both preclinical and clinical evidence suggests that the endogenous opioid system is involved in responses to stress. For example, in animal models opioid agonists reduce isolation distress whereas opioid antagonists increase isolation distress. We recently reported that the mixed mu agonist and kappa antagonist buprenorphine dampened responses to acute psychosocial stress in humans. Now we extend this to study the effects of a pure mu-opioid agonist, hydromorphone, and a non-opioid analgesic, acetaminophen, on response to social stress. We compared the effect of hydromorphone (2 and 4 mg), acetaminophen (1000 mg) to a placebo using a between subject design. Healthy adult volunteers were randomly assigned to receive placebo (N = 13), 2 mg hydromorphone (N = 12), 4 mg hydromorphone (N = 12), or 1000 mg acetaminophen (paracetamol; N = 13) under double-blind conditions before undergoing a stress task or a control task on two separate sessions. The stress task, consisting of a standardized speaking task and the non-stressful control task were presented in counterbalanced order. Dependent measures included mood ratings, subjective appraisal of the stress (or no-stress) task, salivary cortisol, pupil diameter, heart rate, and blood pressure. The stress task produced its expected increase in heart rate, blood pressure, salivary cortisol, pupil diameter, and subjective ratings of anxiety and negative mood. Hydromorphone dose-dependently dampened cortisol responses to stress, and decreased ratings of how "challenging" participants found the task. Acetaminophen did not affect physiological responses, but, like hydromorphone, decreased ratings of how "challenging" the task was. The hydromorphone results support the idea that the mu-opioid system is involved in physiological responses to acute stress in humans, in line with results from preclinical studies. The non-opioid analgesic acetaminophen did not dampen physiological responses, but did reduce some components of psychological stress. It remains to be determined how both opioid and non-opioid systems mediate the complex physiological and psychological responses to social stress. Copyright © 2018 Elsevier Inc. All rights reserved.

Effects of bilateral eye movements on the retrieval of item, associative, and contextual information.

PubMed

Parker, Andrew; Relph, Sarah; Dagnall, Neil

2008-01-01

Two experiments are reported that investigate the effects of saccadic bilateral eye movements on the retrieval of item, associative, and contextual information. Experiment 1 compared the effects of bilateral versus vertical versus no eye movements on tests of item recognition, followed by remember-know responses and associative recognition. Supporting previous research, bilateral eye movements enhanced item recognition by increasing the hit rate and decreasing the false alarm rate. Analysis of remember-know responses indicated that eye movement effects were accompanied by increases in remember responses. The test of associative recognition found that bilateral eye movements increased correct responses to intact pairs and decreased false alarms to rearranged pairs. Experiment 2 assessed the effects of eye movements on the recall of intrinsic (color) and extrinsic (spatial location) context. Bilateral eye movements increased correct recall for both types of context. The results are discussed within the framework of dual-process models of memory and the possible neural underpinnings of these effects are considered.

Participation rates, response bias and response behaviours in the community survey of the Swiss Spinal Cord Injury Cohort Study (SwiSCI).

PubMed

Fekete, Christine; Segerer, Wolfgang; Gemperli, Armin; Brinkhof, Martin W G

2015-10-08

Surveying persons with disabilities is challenging, as targeted subjects may experience specific barriers to survey participation. Here we report on participation rates and response behaviour in a community survey of people with spinal cord injury (SCI) in Switzerland. The cross-sectional survey was implemented as part of the Swiss Spinal Cord Injury Cohort Study (SwiSCI) and represents the largest population-based SCI survey in Europe including nearly 2000 persons. Design features to enhance participation rates included the division of the questionnaire volume over three successive modules; recurrent and mixed-mode reminding of non-responders; and mixed-mode options for response. We describe participation rates of the SwiSCI community survey (absolute and cumulative cooperation, contact, response, and attrition rates) and report on response rates in relation to recruitment efforts. Potential non-response bias and the association between responders' characteristics and response behaviour (response speed: reminding until participation; response mode: paper-pencil vs. online completion) were assessed using regression modelling. Over the successive modules, absolute response rates were 61.1, 80.6 and 87.3% which resulted in cumulative response rates of 49.3 and 42.6% for the second and third modules. Written reminders effectively increased response rates, with the first reminder showing the largest impact. Telephone reminders, partly with direct telephone interviewing, enhanced response rate to the first module, but were essentially redundant in subsequent modules. Non-response to the main module was related to current age, membership of Swiss Paraplegic Association (SPA) and time since injury, but not to gender, lesion level and preferred language of response. Response speed increased with household income, but was not associated to other sociodemographic factors, lesion characteristics or health indicators. We found significant associations between online completion and male gender, younger age, higher education, higher income, SPA membership, tetraplegia, longer time since injury, higher quality of life, and more participation restrictions. In this sample with little non-response bias, recurrent and mixed-mode reminding and mixed-mode options for response were key features of optimizing survey design.

Disruptant effects of 4-allylanisole and verbenone on Tomicus piniperda (Coleoptera: Scolitidae) response to baited traps and logs

Treesearch

Robert A. Haack; Robert K. Lawrence; Toby R. Petrice; Therese M. Poland

2004-01-01

We assessed the inhibitory effects of the host compound 4-allylanisole (release rates = 1 and 2 mg/d in 1994, and 1 and 10 mg/d in 2001) on the response of the pine shoot beetle, Tomicus piniperda (L.), adults to funnel traps baited with the attractant host compound α-pinene (release rate = 150 mg/d) in two pine Christmas tree...

The effect of endotoxin on heart rate dynamics in diabetic rats.

PubMed

Meamar, Morvarid; Dehpour, Tara; Mazloom, Roham; Sharifi, Fatemeh; Raoufy, Mohammad R; Dehpour, Ahmad R; Mani, Ali R

2015-05-01

The effect of endotoxin on heart rate variability (HRV) was assessed in diabetic and controls rats using a telemetric system. Endotoxin induced a reduction in sample entropy of cardiac rhythm in control animals. However, this effect was significantly blunted in streptozotocin-induced diabetic rats. Since uncoupling of cardiac pacemaker from cholinergic control is linked to reduced HRV in endotoxemia, chronotropic responsiveness to cholinergic stimulation was assessed in isolated atria. Endotoxemia was associated with impaired responsiveness to carbacholine in control rats. However, endotoxemia did not impair cholinergic responsiveness in diabetic atria. These findings corroborates with development of endotoxin tolerance in diabetic rats. Copyright © 2014 Elsevier B.V. All rights reserved.

78 FR 75484 - Federal Management Regulation (FMR); Shipping Household Goods

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-12

... information on the commuted rate schedule and correct a Web site address. Commuted rate and actual expense are... commuted rate method. Using the commuted rate method, the individual assumes responsibility for shipment and payment. The commuted rate schedule establishes the reimbursement rate. DATES: Effective Date...

The effect of nonlocal dielectric response on the surface-enhanced Raman and fluorescence spectra of molecular systems

NASA Astrophysics Data System (ADS)

Wei, Yong; Pei, Huan; Li, Li; Zhu, Yanying

2018-06-01

We present a theoretical study on the influence of the nonlocal dielectric response on surface-enhanced resonant Raman scattering (SERRS) and fluorescence (SEF) spectra of a model molecule confined in the center of a Ag nanoparticle (NP) dimer. In the simulations, the nonlocal dielectric response caused by the electron–hole pair generation in Ag NPs was computed with the d-parameter theory, and the scattering spectra of a model molecule representing the commonly used fluorescent dye rhodamine 6G (R6G) were obtained by density-matrix calculations. The influence of the separation between Ag NP dimers on the damping rate and scattering spectra with and without the nonlocal response were systematically analyzed. The results show that the nonlocal dielectric response is very sensitive to the gap distance of the NP dimers, and it undergoes much faster decay with the increase of the separation than the radiative and energy transfer rates. The Raman and fluorescence peaks as simulated with the nonlocal dielectric response are relative weaker than that without the nonlocal effect for smaller NP separations because the extra decay rates of the nonlocal effect could reduce both the population of the excited state and the interband coherence between the ground and excited states. Our result also indicates that the nonlocal effect is more prominent on the SEF process than the SERRS process.

The effect of nonlocal dielectric response on the surface-enhanced Raman and fluorescence spectra of molecular systems.

PubMed

Wei, Yong; Pei, Huan; Li, Li; Zhu, Yanying

2018-05-04

We present a theoretical study on the influence of the nonlocal dielectric response on surface-enhanced resonant Raman scattering (SERRS) and fluorescence (SEF) spectra of a model molecule confined in the center of a Ag nanoparticle (NP) dimer. In the simulations, the nonlocal dielectric response caused by the electron-hole pair generation in Ag NPs was computed with the d-parameter theory, and the scattering spectra of a model molecule representing the commonly used fluorescent dye rhodamine 6G (R6G) were obtained by density-matrix calculations. The influence of the separation between Ag NP dimers on the damping rate and scattering spectra with and without the nonlocal response were systematically analyzed. The results show that the nonlocal dielectric response is very sensitive to the gap distance of the NP dimers, and it undergoes much faster decay with the increase of the separation than the radiative and energy transfer rates. The Raman and fluorescence peaks as simulated with the nonlocal dielectric response are relative weaker than that without the nonlocal effect for smaller NP separations because the extra decay rates of the nonlocal effect could reduce both the population of the excited state and the interband coherence between the ground and excited states. Our result also indicates that the nonlocal effect is more prominent on the SEF process than the SERRS process.

Simultaneous effect of temperature, cyanide and ammonia-oxidizing bacteria concentrations on ammonia oxidation.

PubMed

Do, Hyojin; Lim, Juntaek; Shin, Seung Gu; Wu, Yi-Ju; Ahn, Johng-Hwa; Hwang, Seokhwan

2008-11-01

For biological nitrification, a set of experiments were carried out to approximate the response of lag period along with ammonia oxidation rate with respect to different concentrations of cyanide (CN-) and ammonia-oxidizing bacteria (AOB), and temperature variation in laboratory-scale batch reactors. The effects of simultaneous changes in these three factors on ammonia oxidation were quantitatively estimated and modeled using response surface analysis. The lag period and the ammonia oxidation rate responded differently to changes in the three factors. The lag period and the ammonia oxidation rate were significantly affected by the CN- and AOB concentrations, while temperature changes only affected the ammonia oxidation rate. The increase of AOB concentration and temperature alleviated the inhibition effect of cyanide on ammonia oxidation. The statistical method used in this study can be extended to estimate the quantitative effects of other environmental factors that can change simultaneously.

Additive effects on the energy barrier for synaptic vesicle fusion cause supralinear effects on the vesicle fusion rate.

PubMed

Schotten, Sebastiaan; Meijer, Marieke; Walter, Alexander Matthias; Huson, Vincent; Mamer, Lauren; Kalogreades, Lawrence; ter Veer, Mirelle; Ruiter, Marvin; Brose, Nils; Rosenmund, Christian; Sørensen, Jakob Balslev; Verhage, Matthijs; Cornelisse, Lennart Niels

2015-04-14

The energy required to fuse synaptic vesicles with the plasma membrane ('activation energy') is considered a major determinant in synaptic efficacy. From reaction rate theory, we predict that a class of modulations exists, which utilize linear modulation of the energy barrier for fusion to achieve supralinear effects on the fusion rate. To test this prediction experimentally, we developed a method to assess the number of releasable vesicles, rate constants for vesicle priming, unpriming, and fusion, and the activation energy for fusion by fitting a vesicle state model to synaptic responses induced by hypertonic solutions. We show that complexinI/II deficiency or phorbol ester stimulation indeed affects responses to hypertonic solution in a supralinear manner. An additive vs multiplicative relationship between activation energy and fusion rate provides a novel explanation for previously observed non-linear effects of genetic/pharmacological perturbations on synaptic transmission and a novel interpretation of the cooperative nature of Ca(2+)-dependent release.

Reducing questionnaire length did not improve physician response rate: a randomized trial.

PubMed

Bolt, Eva E; van der Heide, Agnes; Onwuteaka-Philipsen, Bregje D

2014-04-01

To examine the effect of reducing questionnaire length on the response rate in a physician survey. A postal four double-page questionnaire on end-of-life decision making was sent to a random sample of 1,100 general practitioners, 400 elderly care physicians, and 500 medical specialists. Another random sample of 500 medical specialists received a shorter questionnaire of two double pages. After 3 months and one reminder, all nonresponding physicians received an even shorter questionnaire of one double page. Total response was 64% (1,456 of 2,269 eligible respondents). Response rate of medical specialists for the four double-page questionnaire was equal to that of the two double-page questionnaire (190 and 191 questionnaires were returned, respectively). The total response rate increased from 53% to 64% after sending a short one double-page questionnaire (1,203-1,456 respondents). The results of our study suggest that reducing the length of a long questionnaire in a physician survey does not necessarily improve response rate. To improve response rate and gather more information, researchers could decide to send a drastically shortened version of the questionnaire to nonresponders. Copyright © 2014 Elsevier Inc. All rights reserved.

Effects of Culture and Gender on Judgments of Intent and Responsibility

PubMed Central

Plaks, Jason E.; Fortune, Jennifer L.; Liang, Lindie H.; Robinson, Jeffrey S.

2016-01-01

Do different cultures hold different views of intentionality? In four studies, participants read scenarios in which the actor’s distal intent (a focus on a broader goal) and proximal intent (a focus on the mechanics of the act) were manipulated. In Studies 1–2, when distal intent was more prominent in the actor’s mind, North Americans rated the actor more responsible than did Chinese and South Asian participants. When proximal intent was more prominent, Chinese and South Asian participants, if anything, rated the actor more responsible. In Studies 3–4, when distal intent was more prominent, male Americans rated the actor more responsible than did female Americans. When proximal intent was more prominent, females rated the actor more responsible. The authors discuss these findings in relation to the literatures on moral reasoning and cultural psychology. PMID:27123858

Effect of shaping sensor data on pilot response

NASA Technical Reports Server (NTRS)

Bailey, Roger M.

1990-01-01

The pilot of a modern jet aircraft is subjected to varying workloads while being responsible for multiple, ongoing tasks. The ability to associate the pilot's responses with the task/situation, by modifying the way information is presented relative to the task, could provide a means of reducing workload. To examine the feasibility of this concept, a real time simulation study was undertaken to determine whether preprocessing of sensor data would affect pilot response. Results indicated that preprocessing could be an effective way to tailor the pilot's response to displayed data. The effects of three transformations or shaping functions were evaluated with respect to the pilot's ability to predict and detect out-of-tolerance conditions while monitoring an electronic engine display. Two nonlinear transformations, on being the inverse of the other, were compared to a linear transformation. Results indicate that a nonlinear transformation that increases the rate-or-change of output relative to input tends to advance the prediction response and improve the detection response, while a nonlinear transformation that decreases the rate-of-change of output relative to input tends to lengthen the prediction response and make detection more difficult.

Effects of music intervention on physiological stress response and anxiety level of mechanically ventilated patients in China: a randomised controlled trial.

PubMed

Han, Lin; Li, Ji P; Sit, Janet W H; Chung, Loretta; Jiao, Zuo Y; Ma, Wei G

2010-04-01

To examine the effects of music intervention on the physiological stress response and the anxiety level among mechanically ventilated patients in intensive care unit. Despite the fact that previous studies have found music interventions to be effective in stress and anxiety reduction, effects of music on the Chinese population are inconclusive and warranted systematic study to evaluate its effect fully for a different Asian culture. A randomised placebo-controlled trial. A total of 137 patients receiving mechanical ventilation were randomly assigned to either music listening group, headphone group or control group. Outcome measures included the Chinese version of Spielberger State-Trait Anxiety Scale and physiological parameters (heart rate, respiratory rate, saturation of oxygen and blood pressure). Comparison of mean differences (pretest score-posttest score) showed significant differences in heart rate, respiratory rate, systolic blood pressure and diastolic blood pressure as well as the Chinese version of Spielberger State-Trait Anxiety Scale, but not in SaO(2) among the three groups (ranging from p < 0.001 to p = 0.007), of which greater mean differences were found in music listening group. A significant reduction in physiological stress response (heart rate and respiratory rate) over time was found in music listening group (p < 0.001 for both variables) and a significant increase in heart rate and respiratory rate over time in control group (p < 0.001 and p = 0.032), with no significant change over time in headphone group. Within group pretest-posttest comparison of the Chinese version of Spielberger State-Trait Anxiety Scale demonstrated a significant reduction in anxiety for the music listening group (p < 0.001) and headphone group (p < 0.001) but not the control group. Our findings confirm that short-term therapeutic effects of music listening results in substantial reduction in physiological stress responses arising from anxiety in mechanically ventilated patients. Music as a non-pharmacological nursing intervention can be used as complementary adjunct in the care of patients with low-energy states who tire easily, such as those requiring mechanical ventilator support.

Sustained virological response and baseline predictors in HIV-HCV coinfected patients retreated with pegylated interferon and ribavirin after failing a previous interferon-based therapy: systematic review and meta-analysis.

PubMed

Basso, Monica; Parisi, Saverio Giuseppe; Mengoli, Carlo; Gentilini, Valeria; Menegotto, Nicola; Monticelli, Jacopo; Nicolè, Stefano; Cruciani, Mario; Palù, Giorgio

2013-01-01

Published data on retreatment with pegylated interferon and ribavirin of previously failing HIV-HCV coinfected patients are sparse and limited to observational study. We aimed to evaluate efficacy and pretreatment predictors. Systematic review and meta-analysis of observational studies. The overall and genotype-related success rate was investigated. A direct comparison was performed between genotypes 1/4 and 2/3 by evaluating the sustained virological response (SVR) rate ratio (RR). The effect of study level variables on the effect size was investigated by meta-regression. Variables that were analyzed included age, gender, advanced hepatic fibrosis, pretreatment of HCV RNA and CD4, and successful antiretroviral treatment (ART). The available evidence was from 5 open-label, cohort studies (275 patients). The overall SVR rate was 0.280 (95% CI,0.171-0.425). The SVR rate in genotype 1/4 infections was 0.174 (95% CI, 0.129-0.230), and in genotype 2/3 infections it was 0.474 (95% CI, 0.286-0.670). The pooled RR comparing the SVR of genotype 1/4 to 2/3 was 0.369 (95% CI, 0.239-0.568), with a decreased probability of response for genotype 1/4 (P < .001). HIV RNA suppression had a significant effect on SVR (P = .005). The other covariates had no effect on the overall SVR rate. The overall SVR rate was 28%, consistent with the rate reported in the retreatment of mono-infected patients with the same schedule. A substantial relative reduction in the SVR rate of about one-third, when treating genotypes 1/4, was found, with a low SVR rate of 17%. Successful HIV suppression by ART predicted a higher rate of treatment success.

The Effects of Two Types of Appeal on Survey Response Rates.

ERIC Educational Resources Information Center

Green, Kathy E.; And Others

The effects of two cover letter manipulations and their interactions with demographic variables on response to the initial mailing of a survey were investigated. The two manipulations, type of appeal and type of respondent group identification, were intended to affect respondents' perceptions of their social responsibility and position. In all,…

Physiological responses to the Coriolis illusion: effects of head position and vision.

PubMed

Westmoreland, David; Krell, Robert W; Self, Brian P

2007-10-01

Changes in sympathetic outflow during Type II spatial disorientation are well documented. In this study we investigated the influences of head position and eye state (open or closed) on sympathetic activation. There were 11 naive subjects (6 men, 5 women) who were tested in a General Aviation Trainer that accelerated at a subthreshold rate for 60 s until a constant angular velocity of 90 degrees x s(-1) was reached. Approximately 40 s later, subjects were instructed to tilt their heads along either the pitch or roll axis, stimulating a Coriolis illusion. Subjects reported the perceived intensity and duration of disorientation. Heart rate, heart rate variability, and electrodermal responses were recorded before, during, and after the period of disorientation. Each subject completed four trials, which were crossed combinations of head position and eye state. There were significant increases in heart rate and the electrodermal response during disorientation, but no significant change in heart rate variability. Head position had no significant effect on any physiological parameters or on the perceived intensity of disorientation; subjects reported a shorter duration of disorientation when the head was tilted into the roll versus the pitch axis. Eye state had no effect on heart rate, heart rate variability, or the intensity of disorientation, but the electrodermal response was somewhat greater, and the duration of disorientation shorter when eyes were open. The results suggest that head position and eye state (open or closed) do not need to be included as factors when investigating sympathetic outflow during a mild Coriolis illusion.

A comparison of the effects of psychotomimetics and anxiolytics on punished and unpunished responding maintained by fixed interval schedules of food reinforcement in the rat.

PubMed

Evenden, John; Duncan, Bertina; Ko, Tracey

2006-02-01

Characterization of anxiolytic drugs often employs conflict paradigms in which the drug effects on punished and unpunished responding can be compared. In this study, a fixed interval schedule generating a range of baseline response rates allowed comparison of the effects of anxiolytic drugs with those of psychotomimetic drugs on equivalent and differing rates of punished and unpunished responding. The first response made by the rat after a 40-s fixed interval elapsed resulted in food pellet delivery. In punished intervals, signalled by the illumination of stimulus lamps above each lever, a 0.6-mA shock was delivered after every 20th response, resulting in a lower rate of responding than that in the unpunished intervals. Three psychotomimetic agents, D-amphetamine, MK801 and DOI were compared with the anxiolytics chlordiazepoxide, NS2710 and pregabalin. The three psychotomimetics preferentially increased rates of unpunished responding compared with those of punished responding. Chlordiazepoxide, NS2710 and, to a lesser extent, pregabalin increased rates of both unpunished and punished responding. In comparison studies, yohimbine also increased rates of both unpunished and punished responding whereas the antidepressant citalopram had no effect. In conclusion, stable baseline performance over many months allowed the direct comparison of several different drugs in the same subjects with no need to adjust shock levels or equate baseline response rates. The drugs had systematic and replicable effects in this procedure, which, in the case of amphetamine and chlordiazepoxide, were similar to those in other species, and psychotomimetic drugs could clearly be distinguished from anxiolytic drugs. The procedure, however, has limited value for characterizing novel anxiolytic agents as the examples used here increased punished and unpunished responding to the same extent, and were indistinguishable in that regard from the clinically anxiogenic agent, yohimbine.

[A multi-measure analysis of the similarity, attraction, and compromise effects in multi-attribute decision making].

PubMed

Tsuzuki, Takashi; Matsui, Hiroshi; Kikuchi, Manabu

2012-12-01

In multi-attribute decision making, the similarity, attraction, and compromise effects warrant specific investigation as they cause violations of principles in rational choice. In order to investigate these three effects simultaneously, we assigned 145 undergraduates to three context effect conditions. We requested them to solve the same 20 hypothetical purchase problems, each of which had three alternatives described along two attributes. We measured their choices, confidence ratings, and response times. We found that manipulating the third alternative had significant context effects for choice proportions and confidence ratings in all three conditions. Furthermore, the attraction effect was the most prominent with regard to choice proportions. In the compromise effect condition, although the choice proportion of the third alternative was high, the confidence rating was low and the response time was long. These results indicate that the relationship between choice proportions and confidence ratings requires further theoretical investigation. They also suggest that a combination of experimental and modeling studies is imperative to reveal the mechanisms underlying the context effects in multi-attribute, multi-alternative decision making.

Hydrostatic Stress Effects Incorporated Into the Analysis of the High-Strain-Rate Deformation of Polymer Matrix Composites

NASA Technical Reports Server (NTRS)

Goldberg, Robert K.; Roberts, Gary D.

2003-01-01

Procedures for modeling the effect of high strain rate on composite materials are needed for designing reliable composite engine cases that are lighter than the metal cases in current use. The types of polymer matrix composites that are likely to be used in such an application have a deformation response that is nonlinear and that varies with strain rate. The nonlinearity and strain rate dependence of the composite response is primarily due to the matrix constituent. Therefore, in developing material models to be used in the design of impact-resistant composite engine cases, the deformation of the polymer matrix must be correctly analyzed. However, unlike in metals, the nonlinear response of polymers depends on the hydrostatic stresses, which must be accounted for within an analytical model. An experimental program has been carried out through a university grant with the Ohio State University to obtain tensile and shear deformation data for a representative polymer for strain rates ranging from quasi-static to high rates of several hundred per second. This information has been used at the NASA Glenn Research Center to develop, characterize, and correlate a material model in which the strain rate dependence and nonlinearity (including hydrostatic stress effects) of the polymer are correctly analyzed. To obtain the material data, Glenn s researchers designed and fabricated test specimens of a representative toughened epoxy resin. Quasi-static tests at low strain rates and split Hopkinson bar tests at high strain rates were then conducted at the Ohio State University. The experimental data confirmed the strong effects of strain rate on both the tensile and shear deformation of the polymer. For the analytical model, Glenn researchers modified state variable constitutive equations previously used for the viscoplastic analysis of metals to allow for the analysis of the nonlinear, strain-rate-dependent polymer deformation. Specifically, we accounted for the effects of hydrostatic stresses. An important discovery in the course of this work was that the hydrostatic stress effects varied during the loading process, which needed to be accounted for within the constitutive equations. The model is characterized primarily by shear data, with tensile data used to characterize the hydrostatic stress effects.

Administration of ketamine for unipolar and bipolar depression.

PubMed

Kraus, Christoph; Rabl, Ulrich; Vanicek, Thomas; Carlberg, Laura; Popovic, Ana; Spies, Marie; Bartova, Lucie; Gryglewski, Gregor; Papageorgiou, Konstantinos; Lanzenberger, Rupert; Willeit, Matthäus; Winkler, Dietmar; Rybakowski, Janusz K; Kasper, Siegfried

2017-03-01

Clinical trials demonstrated that ketamine exhibits rapid antidepressant efficacy when administered in subanaesthetic dosages. We reviewed currently available literature investigating efficacy, response rates and safety profile. Twelve studies investigating unipolar, seven on bipolar depression were included after search in medline, scopus and web of science. Randomized, placebo-controlled or open-label trials reported antidepressant response rates after 24 h on primary outcome measures at 61%. The average reduction of Hamilton Depression Rating Scale (HAM-D) was 10.9 points, Beck Depression Inventory (BDI) 15.7 points and Montgomery-Asberg Depression Rating Scale (MADRS) 20.8 points. Ketamine was always superior to placebo. Most common side effects were dizziness, blurred vision, restlessness, nausea/vomiting and headache, which were all reversible. Relapse rates ranged between 60% and 92%. To provide best practice-based information to patients, a consent-form for application and modification in local language is included. Ketamine constitutes a novel, rapid and efficacious treatment option for patients suffering from treatment resistant depression and exhibits rapid and significant anti-suicidal effects. New administration routes might serve as alternative to intravenous regimes for potential usage in outpatient settings. However, long-term side effects are not known and short duration of antidepressant response need ways to prolong ketamine's efficacy.

Pore-scale investigation on the response of heterotrophic respiration to moisture conditions in heterogeneous soils

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yan, Zhifeng; Liu, Chongxuan; Todd-Brown, Katherine E.

The relationship between microbial respiration rate and soil moisture content is an important property for understanding and predicting soil organic carbon degradation, CO 2 production and emission, and their subsequent effects on climate change. This paper reports a pore-scale modeling study to investigate the response of heterotrophic respiration to moisture conditions in soils and to evaluate various factors that affect this response. X-ray computed tomography was used to derive soil pore structures, which were then used for pore-scale model investigation. The pore-scale results were then averaged to calculate the effective respiration rates as a function of water content in soils.more » The calculated effective respiration rate first increases and then decreases with increasing soil water content, showing a maximum respiration rate at water saturation degree of 0.75 that is consistent with field and laboratory observations. The relationship between the respiration rate and moisture content is affected by various factors, including pore-scale organic carbon bioavailability, the rate of oxygen delivery, soil pore structure and physical heterogeneity, soil clay content, and microbial drought resistivity. Simulations also illustrates that a larger fraction of CO 2 produced from microbial respiration can be accumulated inside soil cores under higher saturation conditions, implying that CO 2 flux measured on the top of soil cores may underestimate or overestimate true soil respiration rates under dynamic moisture conditions. Overall, this study provides mechanistic insights into the soil respiration response to the change in moisture conditions, and reveals a complex relationship between heterotrophic microbial respiration rate and moisture content in soils that is affected by various hydrological, geochemical, and biophysical factors.« less

Surface effects on the radiation response of nanoporous Au foams

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fu, E. G.; Caro, M.; Wang, Y. Q.

2012-11-05

We report on an experimental and simulation campaign aimed at exploring the radiation response of nanoporous Au (np-Au) foams. We find different defect accumulation behavior by varying radiation dose-rate in ion-irradiated np-Au foams. Stacking fault tetrahedra are formed when np-Au foams are irradiated at high dose-rate, but they do not seem to be formed in np-Au at low dose-rate irradiation. A model is proposed to explain the dose-rate dependent defect accumulation based on these results.

Influence of cochlear traveling wave and neural adaptation on auditory brainstem responses.

PubMed

Junius, Dirk; Dau, Torsten

2005-07-01

The present study investigates the relationship between evoked responses to transient broadband chirps and responses to the same chirps when embedded in longer-duration stimuli. It examines to what extent the responses to the composite stimuli can be explained by a linear superposition of the responses to the single components, as a function of stimulus level. In the first experiment, a single rising chirp was temporally and spectrally embedded in two steady-state tones. In the second experiment, the stimulus consisted of a continuous alternating train of chirps: each rising chirp was followed by the temporally reversed (falling) chirp. In both experiments, the transitions between stimulus components were continuous. For stimulation levels up to approximately 70 dB SPL, the responses to the embedded chirp corresponded to the responses to the single chirp. At high stimulus levels (80-100 dB SPL), disparities occurred between the responses, reflecting a nonlinearity in the processing when neural activity is integrated across frequency. In the third experiment, the effect of within-train rate on wave-V response was investigated. The response to the chirp presented at a within-train rate of 95 Hz exhibited the same amplitude as that to the chirp presented in the traditional single-stimulus paradigm at a rate of 13 Hz. For a corresponding experiment with bandlimited chirps of 4 ms duration, where the within-train rate was 250 Hz, a clear reduction of the response amplitude was observed. This nonlinearity in terms of temporal processing most likely reflects effects of short-term adaptation. Overall, the results of the present study further demonstrate the importance of cochlear processing for the formation of brainstem potentials. The data may provide constraints on future models of peripheral processing in the human auditory system. The findings might also be useful for the development of effective stimulation paradigms in clinical applications.

Optimization of Adhesive Pastes for Dental Caries Prevention.

PubMed

Sodata, Patteera; Juntavee, Apa; Juntavee, Niwut; Peerapattana, Jomjai

2017-11-01

Dental caries prevention products available on the market contain only remineralizing agents or antibacterial agents. This study aimed to develop adhesive pastes containing calcium phosphate and α-mangostin for dental caries prevention using the optimization technique. Calcium phosphate was used as a remineralizing agent, and extracted α-mangostin was used as an antibacterial agent. The effect of the independent variables, which were fumed silica, Eudragit ® EPO, polyethylene glycol, and ethyl alcohol, on the responses was investigated. The drying time, erosion rate, calcium release rate, and α-mangostin release rate were established as the measured responses. An equation and a model of the relationship were constructed. An optimal formulation was obtained, and its effect on dental caries prevention was investigated using the pH-cycling model. The quadratic equation revealed that the drying time, calcium release rate, and α-mangostin release rate tended to decrease when increasing the fumed silica and decreasing other factors. The erosion rate tended to increase when decreasing Eudragit ® EPO and increasing other factors. The observed responses of the optimal adhesive pastes were not significantly different from the predicted responses. This result demonstrated that optimization is an efficient technique in the formulation development of the adhesive pastes. In addition, the optimal adhesive pastes could enhance acid resistance activity to the tooth enamel.

The Decision To Recruit Online: A Descriptive Study.

ERIC Educational Resources Information Center

Galanaki, Eleanna

2002-01-01

Responses from 34 of 99 United Kingdom information technology companies explored effects of cost effectiveness, response rate and quality, company image, targeting, time and effort, and overload. The effectiveness of online recruiting depends largely on its implementation and the quality of the recruitment process as a whole. (Contains 38…

An Investigation of Large Tilt-Rotor Hover and Low Speed Handling Qualities

NASA Technical Reports Server (NTRS)

Malpica, Carlos A.; Decker, William A.; Theodore, Colin R.; Lindsey, James E.; Lawrence, Ben; Blanken, Chris L.

2011-01-01

A piloted simulation experiment conducted on the NASA-Ames Vertical Motion Simulator evaluated the hover and low speed handling qualities of a large tilt-rotor concept, with particular emphasis on longitudinal and lateral position control. Ten experimental test pilots evaluated different combinations of Attitude Command-Attitude Hold (ACAH) and Translational Rate Command (TRC) response types, nacelle conversion actuator authority limits and inceptor choices. Pilots performed evaluations in revised versions of the ADS-33 Hover, Lateral Reposition and Depart/Abort MTEs and moderate turbulence conditions. Level 2 handling qualities ratings were primarily recorded using ACAH response type in all three of the evaluation maneuvers. The baseline TRC conferred Level 1 handling qualities in the Hover MTE, but there was a tendency to enter into a PIO associated with nacelle actuator rate limiting when employing large, aggressive control inputs. Interestingly, increasing rate limits also led to a reduction in the handling qualities ratings. This led to the identification of a nacelle rate to rotor longitudinal flapping coupling effect that induced undesired, pitching motions proportional to the allowable amount of nacelle rate. A modification that counteracted this effect significantly improved the handling qualities. Evaluation of the different response type variants showed that inclusion of TRC response could provide Level 1 handling qualities in the Lateral Reposition maneuver by reducing coupled pitch and heave off axis responses that otherwise manifest with ACAH. Finally, evaluations in the Depart/Abort maneuver showed that uncertainty about commanded nacelle position and ensuing aircraft response, when manually controlling the nacelle, demanded high levels of attention from the pilot. Additional requirements to maintain pitch attitude within 5 deg compounded the necessary workload.

Nitrogen deposition and forest carbon sequestration: a quantitative synthesis from plot to global scales

NASA Astrophysics Data System (ADS)

Goodale, C. L.; Thomas, R. Q.; Dentener, F. J.; Adams, M.; Baron, J.; Emmett, B.; Evans, C. B.; Fernandez, I. J.; Gundersen, P.; Hagedorn, F.; Kulmatiski, A.; Lovett, G. M.; McNulty, S.; Melvin, A. M.; Moldan, F.; Ollinger, S. V.; Schleppi, P.; Weiss, M.

2009-12-01

Atmospheric nitrogen deposition has long been proposed as a driver of terrestrial carbon sequestration, but its quantitative effect remains poorly constrained. Global models, observations along N deposition gradients, and plot-level forest N-addition experiments provide a range of estimates of the amount of C sequestered in response to added N. Synthesis of results from 48 multi-year N-addition studies in temperate forests show responses ranging from +53 to -95 kg C of live tree production per unit of N addition. Negative effects on live tree C occurred in stands with low rates of biomass accumulation, and occurred more rapidly with higher N application rates. More positive effects occurred in younger stands, and with greater efficiency of C gain at lower N addition rates. Observations of tree growth along N deposition gradients in Europe and the eastern U.S. produced broadly similar tree growth responses (19-56 kg C/kg N) as the N addition experiments. Soil C response increased with N addition rate, and averaged 4 + 12 kg C/kg N. These surface soil responses suggest modest suppression of soil decomposition induced by added N in some but not all sites due to several possible mechanisms, none of which are yet considered in global models. Global-scale estimates of N deposition effects on forest C sequestration have ranged from 0.1 to 2.0 Pg C/y depending on assumptions on the rate of N deposition to forests, its fate, and the C:N ratios of recipient C pools. A new group of biogeochemistry models designed for coupling with global climate models all simulate relatively limited terrestrial C sinks from atmospheric N deposition alone (0.2 - 0.4 PgC/y), more in combination with rising atmospheric CO2. Future model projections should benefit from rigorous comparisons with the range of observed C responses reviewed here.

Self-Paced Exercise, Affective Response, and Exercise Adherence: A Preliminary Investigation Using Ecological Momentary Assessment.

PubMed

Williams, David M; Dunsiger, Shira; Emerson, Jessica A; Gwaltney, Chad J; Monti, Peter M; Miranda, Robert

2016-06-01

Affective response to exercise may mediate the effects of self-paced exercise on exercise adherence. Fiftynine low-active (exercise <60 min/week), overweight (body mass index: 25.0-39.9) adults (ages 18-65) were randomly assigned to self-paced (but not to exceed 76% maximum heart rate) or prescribed moderate intensity exercise (64-76% maximum heart rate) in the context of otherwise identical 6-month print-based exercise promotion programs. Frequency and duration of exercise sessions and affective responses (good/bad) to exercise were assessed via ecological momentary assessment throughout the 6-month program. A regression-based mediation model was used to estimate (a) effects of experimental condition on affective response to exercise (path a = 0.20, SE = 0.28, f 2 = 0.02); (b) effects of affective response on duration/latency of the next exercise session (path b = 0.47, SE = 0.25, f 2 = 0.04); and (c) indirect effects of experimental condition on exercise outcomes via affective response (path ab = 0.11, SE = 0.06, f 2 = 0.10). Results provide modest preliminary support for a mediational pathway linking self-paced exercise, affective response, and exercise adherence.

Enhanced styrene recovery from waste polystyrene pyrolysis using response surface methodology coupled with Box-Behnken design.

PubMed

Mo, Yu; Zhao, Lei; Wang, Zhonghui; Chen, Chia-Lung; Tan, Giin-Yu Amy; Wang, Jing-Yuan

2014-04-01

A work applied response surface methodology coupled with Box-Behnken design (RSM-BBD) has been developed to enhance styrene recovery from waste polystyrene (WPS) through pyrolysis. The relationship between styrene yield and three selected operating parameters (i.e., temperature, heating rate, and carrier gas flow rate) was investigated. A second order polynomial equation was successfully built to describe the process and predict styrene yield under the study conditions. The factors identified as statistically significant to styrene production were: temperature, with a quadratic effect; heating rate, with a linear effect; carrier gas flow rate, with a quadratic effect; interaction between temperature and carrier gas flow rate; and interaction between heating rate and carrier gas flow rate. The optimum conditions for the current system were determined to be at a temperature range of 470-505°C, a heating rate of 40°C/min, and a carrier gas flow rate range of 115-140mL/min. Under such conditions, 64.52% WPS was recovered as styrene, which was 12% more than the highest reported yield for reactors of similar size. It is concluded that RSM-BBD is an effective approach for yield optimization of styrene recovery from WPS pyrolysis. Copyright © 2014 Elsevier Ltd. All rights reserved.

50 ways to trace your veteran: increasing response rates can be cheap and effective

PubMed Central

Fear, Nicola Townsend; Van Staden, Lauren; Iversen, Amy; Hall, John; Wessely, Simon

2010-01-01

Background while low response rates need not introduce bias into research, having a lower percentage of responders does increase the potential for this to occur. This is of particular concern given the decline that has been occurring in response rates since the 1950s. However, there are various methods that can be incorporated into the study design, which can assist in increasing levels of participation. Objective To outline the methods used by the King's Centre for Military Health Research (KCMHR) when conducting a recent telephone survey of serving and ex-Service military personnel. Design Using participants who had already taken part in a questionnaire-based study on the health effects of serving in the UK Armed Forces (n=10,272), a subsample was selected for an in-depth telephone interview-based follow-up study. The subsample consisted of 1,105 participants, selected on the basis of their mental health status. An adjusted response rate of 76% was achieved (n=821). Results Various methods of contact were used in this study to ensure an adequate response rate was achieved. Conclusions Simple research strategies increase response rates and are likely to reduce bias. Use of multiple simultaneous tracing methods and customisation of the approach to the target population increases rapport between participants, ensuring that those who take part feel valued as members of the study. In the current climate of decreasing participation in studies, research teams need to engage with their study population and devise innovative strategies to keep participants involved in the research being undertaken. PMID:22893795

Reassessment of the cardio-respiratory stress response, using the king penguin as a model.

PubMed

Willener, Astrid S T; Halsey, Lewis G; Strike, Siobhán; Enstipp, Manfred R; Georges, Jean-Yves; Handrich, Yves

2015-01-01

Research in to short-term cardio-respiratory changes in animals in reaction to a psychological stressor typically describes increases in rate of oxygen consumption (V̇(O2)) and heart rate. Consequently, the broad consensus is that they represent a fundamental stressor response generalizable across adult species. However, movement levels can also change in the presence of a stressor, yet studies have not accounted for this possible confound on heart rate. Thus the direct effects of psychological stressors on the cardio-respiratory system are not resolved. We used an innovative experimental design employing accelerometers attached to king penguins (Aptenodytes patagonicus) to measure and thus account for movement levels in a sedentary yet free-to-move animal model during a repeated measures stress experiment. As with previous studies on other species, incubating king penguins (N = 6) exhibited significant increases in both V̇(O2) and heart rate when exposed to the stressor. However, movement levels, while still low, also increased in response to the stressor. Once this was accounted for by comparing periods of time during the control and stress conditions when movement levels were similar as recorded by the accelerometers, only V̇(O2) significantly increased; there was no change in heart rate. These findings offer evidence that changing movement levels have an important effect on the measured stress response and that the cardio-respiratory response per se to a psychological stressor (i.e. the response as a result of physiological changes directly attributable to the stressor) is an increase in V̇(O2) without an increase in heart rate.

Strategies for Increasing Response Rates for Online End-of-Course Evaluations

ERIC Educational Resources Information Center

Chapman, Diane D.; Joines, Jeffrey A.

2017-01-01

Student Evaluations of Teaching (SETs) are used by nearly all public and private universities as one means to evaluate teaching effectiveness. A majority of these universities have transitioned from the traditional paper-based evaluations to online evaluations, resulting in a decline in overall response rates. This has led to scepticism about the…

Effects of Varying Response Formats on Self-Ratings of Life-Satisfaction

ERIC Educational Resources Information Center

Mazaheri, Mehrdad; Theuns, Peter

2009-01-01

A sample of 1,737 volunteering students, randomly assigned to 12 conditions, rated their current overall (dis)satisfaction with life. Each condition used 1 of 12 response formats, differing in (1) "polarity" ("bipolar" versus "unipolar"), (2) "orientation" ("horizontal" versus "vertical"), and (3) "anchoring" (-5 to +5, "Not Numbered," and 0 "to"…

Auditory stream segregation in monkey auditory cortex: effects of frequency separation, presentation rate, and tone duration

NASA Astrophysics Data System (ADS)

Fishman, Yonatan I.; Arezzo, Joseph C.; Steinschneider, Mitchell

2004-09-01

Auditory stream segregation refers to the organization of sequential sounds into ``perceptual streams'' reflecting individual environmental sound sources. In the present study, sequences of alternating high and low tones, ``...ABAB...,'' similar to those used in psychoacoustic experiments on stream segregation, were presented to awake monkeys while neural activity was recorded in primary auditory cortex (A1). Tone frequency separation (ΔF), tone presentation rate (PR), and tone duration (TD) were systematically varied to examine whether neural responses correlate with effects of these variables on perceptual stream segregation. ``A'' tones were fixed at the best frequency of the recording site, while ``B'' tones were displaced in frequency from ``A'' tones by an amount=ΔF. As PR increased, ``B'' tone responses decreased in amplitude to a greater extent than ``A'' tone responses, yielding neural response patterns dominated by ``A'' tone responses occurring at half the alternation rate. Increasing TD facilitated the differential attenuation of ``B'' tone responses. These findings parallel psychoacoustic data and suggest a physiological model of stream segregation whereby increasing ΔF, PR, or TD enhances spatial differentiation of ``A'' tone and ``B'' tone responses along the tonotopic map in A1.

Decision-case mix model for analyzing variation in cesarean rates.

PubMed

Eldenburg, L; Waller, W S

2001-01-01

This article contributes a decision-case mix model for analyzing variation in c-section rates. Like recent contributions to the literature, the model systematically takes into account the effect of case mix. Going beyond past research, the model highlights differences in physician decision making in response to obstetric factors. Distinguishing the effects of physician decision making and case mix is important in understanding why c-section rates vary and in developing programs to effect change in physician behavior. The model was applied to a sample of deliveries at a hospital where physicians exhibited considerable variation in their c-section rates. Comparing groups with a low versus high rate, the authors' general conclusion is that the difference in physician decision tendencies (to perform a c-section), in response to specific obstetric factors, is at least as important as case mix in explaining variation in c-section rates. The exact effects of decision making versus case mix depend on how the model application defines the obstetric condition of interest and on the weighting of deliveries by their estimated "risk of Cesarean." The general conclusion is supported by an additional analysis that uses the model's elements to predict individual physicians' annual c-section rates.

Implementation of Improved Transverse Shear Calculations and Higher Order Laminate Theory Into Strain Rate Dependent Analyses of Polymer Matrix Composites

NASA Technical Reports Server (NTRS)

Zhu, Lin-Fa; Kim, Soo; Chattopadhyay, Aditi; Goldberg, Robert K.

2004-01-01

A numerical procedure has been developed to investigate the nonlinear and strain rate dependent deformation response of polymer matrix composite laminated plates under high strain rate impact loadings. A recently developed strength of materials based micromechanics model, incorporating a set of nonlinear, strain rate dependent constitutive equations for the polymer matrix, is extended to account for the transverse shear effects during impact. Four different assumptions of transverse shear deformation are investigated in order to improve the developed strain rate dependent micromechanics model. The validities of these assumptions are investigated using numerical and theoretical approaches. A method to determine through the thickness strain and transverse Poisson's ratio of the composite is developed. The revised micromechanics model is then implemented into a higher order laminated plate theory which is modified to include the effects of inelastic strains. Parametric studies are conducted to investigate the mechanical response of composite plates under high strain rate loadings. Results show the transverse shear stresses cannot be neglected in the impact problem. A significant level of strain rate dependency and material nonlinearity is found in the deformation response of representative composite specimens.

Temperature-induced physiological stress and reproductive characteristics of the migratory seahorse Hippocampus erectus during a thermal stress simulation.

PubMed

Qin, Geng; Johnson, Cara; Zhang, Yuan; Zhang, Huixian; Yin, Jianping; Miller, Glen; Turingan, Ralph G; Guisbert, Eric; Lin, Qiang

2018-05-15

Inshore-offshore migration occurs frequently in seahorse species either because of prey opportunities or because it is driven by reproduction, and variations in water temperature may dramatically change migratory seahorse behavior and physiology. The present study investigated the behavioral and physiological responses of the lined seahorse Hippocampus erectus under thermal stress and evaluated the potential effects of different temperatures on its reproduction. The results showed that the thermal tolerance of the seahorses was time dependent. Acute thermal stress (30°C, 2-10 hours) increased the basal metabolic rate (breathing rate) and the expression of stress response genes ( Hsp genes) significantly and further stimulated seahorse appetite. Chronic thermal treatment (30°C, 4 weeks) led to a persistently higher basal metabolic rate, higher stress response gene expression, and higher mortality, indicating that the seahorses could not acclimate to chronic thermal stress and might experience massive mortality due to excessive basal metabolic rates and stress damage. Additionally, no significant negative effects on gonad development or reproductive endocrine regulation genes were observed in response to chronic thermal stress, suggesting that seahorse reproductive behavior could adapt to higher-temperature conditions during migration and within seahorse breeding grounds. In conclusion, this simulation experiment indicated that temperature variations during inshore-offshore migration have no effect on reproduction but promote basal metabolic rates and stress responses significantly. Therefore, we suggest that the high observed tolerance of seahorse reproduction was in line with the inshore-offshore reproductive migration pattern of lined seahorse. © 2018. Published by The Company of Biologists Ltd.

Physiological responses and match characteristics in professional tennis players during a one-hour simulated tennis match

PubMed Central

Şenel, Ömer; Arslan, Erşan; Can, Sema

2016-01-01

Abstract The purpose of this study was to investigate the effects of serve and return game situations on physiological responses and match characteristics in professional male tennis players during one hour-long simulated singles tennis matches. Ten internationally ranked tennis players (age 22.2 ± 2.8 years; body height 180.7 ± 4.4 cm; body mass 75.9 ± 8.9 kg) participated in this study. Their physiological responses were measured using two portable analyzers during indoor hard court matches. Ratings of perceived exertion were also determined at the end of the game. The variables describing the characteristics of the matches determined from video recordings were: (a) duration of rallies; (b) rest time; (c) work-to-rest ratio; (d) effective playing time; and (d) strokes per rally. Significant differences (p<0.05) were found between serving and returning conditions in an hour-long simulated singles tennis match in terms of oxygen uptake, a heart rate, ratings of perceived exertion, pulmonary ventilation, respiration frequency and a respiratory gas exchange ratio. In addition, both the heart rate and ratings of perceived exertion responses were moderately correlated with the duration of rallies and strokes per rally (r = 0.60 to 0.26; p<0.05). Taken together, these results indicate that the serve game situation has a significant effect on the physiological response in an hour-long simulated tennis match between professional male tennis players. These findings might be used for the physiological adaptations required for tennis-specific aerobic endurance. PMID:28149371

Complex and interactive effects of ocean acidification and temperature on epilithic and endolithic coral-reef turf algal assemblages

NASA Astrophysics Data System (ADS)

Johnson, Maggie D.; Comeau, Steeve; Lantz, Coulson A.; Smith, Jennifer E.

2017-12-01

Turf algal assemblages are ubiquitous primary producers on coral reefs, but little is known about the response of this diverse group to ocean acidification (OA) across different temperatures. We tested the hypothesis that CO2 influences the functional response of epilithic and endolithic turf assemblages to increasing temperature. Replicate carbonate plugs covered by turf were collected from the reef and exposed to ambient and high pCO2 (1000 µatm) conditions for 3 weeks. Each pCO2 treatment was replicated across six temperatures (24.0-31.5 °C) that spanned the full seasonal temperature range on a fringing reef in Moorea, French Polynesia, and included one warming treatment (3 °C above daily average temperatures). Temperature and CO2 enrichment had complex, and sometimes interactive, effects on turf metabolism and growth. Photosynthetic and respiration rates were enhanced by increasing temperature, with an interactive effect of CO2 enrichment. Photosynthetic rates were amplified by high CO2 in the warmest temperatures, while the increase in respiration rates with temperature were enhanced under ambient CO2. Epilithic turf growth rates were not affected by temperature, but increased in response to CO2 enrichment. We found that CO2 and temperature interactively affected the endolithic assemblage, with the highest growth rates under CO2 enrichment, but only at the warmest temperatures. These results demonstrate how OA may influence algal physiology and growth across a range of ecologically relevant temperatures, and indicate that the effects of CO2 enrichment on coral-reef turf assemblages can be temperature dependent. The complex effects of CO2 enrichment and temperature across a suite of algal responses illustrates the importance of incorporating multiple stressors into global change experiments.

Endurance- and Resistance-Trained Men Exhibit Lower Cardiovascular Responses to Psychosocial Stress Than Untrained Men.

PubMed

Gröpel, Peter; Urner, Maren; Pruessner, Jens C; Quirin, Markus

2018-01-01

Evidence shows that regular physical exercise reduces physiological reactivity to psychosocial stress. However, previous research mainly focused on the effect of endurance exercise, with only a few studies looking at the effect of resistance exercise. The current study tested whether individuals who regularly participate in either endurance or resistance training differ from untrained individuals in adrenal and cardiovascular reactivity to psychosocial stress. Twelve endurance-trained men, 10 resistance-trained men, and 12 healthy but untrained men were exposed to a standardized psychosocial stressor, the Trier Social Stress Test. Measurements of heart rate, free salivary cortisol levels, and mood were obtained throughout the test and compared among the three groups. Overall, both endurance- and resistance-trained men had lower heart rate levels than untrained men, indicating higher cardiac performance of the trained groups. Trained men also exhibited lower heart rate responses to psychosocial stress compared with untrained men. There were no significant group differences in either cortisol responses or mood responses to the stressor. The heart rate results are consistent with previous studies indicating reduced cardiovascular reactivity to psychosocial stress in trained individuals. These findings suggest that long-term endurance and resistance trainings may be related to the same cardiovascular benefits, without exhibiting strong effects on the cortisol reactivity to stress.

Emotion-related hemisphere asymmetry: subjective emotional responses to laterally presented films.

PubMed

Wittling, W; Roschmann, R

1993-09-01

To investigate whether the cerebral hemispheres differ in their subjective emotional responses 54 adult subjects were presented two films of different emotion-related qualities (positive and negative film) either to their left or right hemisphere. The films were exposed by means of a technique for the lateralization of visual input that allows prolonged viewing while permitting free ocular scanning. Subjective emotional responses were assessed by means of a continuous rating of emotional arousal experienced during the movie as well as by retrospective ratings of ten different emotional qualities. Presenting both films to the right hemisphere resulted in stronger subjective responses in the continuous emotion rating as well as in some retrospectively assessed ratings compared to left-hemispheric presentation. The effects were more pronounced for the negative film. Taken together, the findings suggest a higher responsiveness of the right hemisphere in subjective emotional experience.

Win some, lose some: parental hypertension and heart rate change in an incentive versus response cost paradigm.

PubMed

Hastrup, J L; Johnson, C A; Hotchkiss, A P; Kraemer, D L

1986-11-01

Fowles (1983), citing evidence from separate studies, suggests that both incentive and response cost paradigms increase heart rate and should be subsumed under Gray's (1975) 'appetitive motivational system'. Shock avoidance and loss of reward (response cost) contingencies, while aversive, appear to evoke this motivational system; consequently both should elicit heart rate increases independent of anxiety. The present investigation compared magnitude of heart rate changes observed under conditions of winning and losing money. Results showed: no differences between incentive and response cost conditions; no effect of state anxiety on heart rate in these conditions, despite an elevation of state anxiety on the task day relative to a subsequent relaxation day assessment; and some evidence for the presence under both such appetitive conditions of cardiovascular hyperresponsivity among offspring of hypertensive parents. The results suggest a need for systematic parametric studies of experimental conditions.

Increasing response rates to follow-up questionnaires in health intervention research: Randomized controlled trial of a gift card prize incentive.

PubMed

Morgan, Amy J; Rapee, Ronald M; Bayer, Jordana K

2017-08-01

Background/aims Achieving a high response rate to follow-up questionnaires in randomized controlled trials of interventions is important for study validity. Few studies have tested the value of incentives in increasing response rates to online questionnaires in clinical trials of health interventions. This study evaluated the effect of a gift card prize-draw incentive on response rates to follow-up questionnaires within a trial of an online health intervention. Method The study was embedded in a host randomized controlled trial of an online parenting program for child anxiety. A total of 433 participants were randomly allocated to one of two groups: (1) being informed that they would enter a gift card prize-draw if they completed the final study questionnaire (24-week follow-up) and (2) not informed about the prize-draw. All participants had a 1 in 20 chance of winning an AUD50 gift card after they completed the online questionnaire. Results The odds of the informed group completing the follow-up questionnaire were significantly higher than the uninformed group, (79.6% vs 68.5%, odds ratio = 1.79, 95% confidence interval = 1.15-2.79). This response rate increase of 11.1% (95% confidence interval = 2.8-19.1) occurred in both intervention and control groups in the host randomized controlled trial. The incentive was also effective in increasing questionnaire commencement (84.6% vs 75.9%, odds ratio = 1.74, 95% confidence interval = 1.07-2.84) and reducing the delay in completing the questionnaire (19.9 vs 22.6 days, hazard ratio = 1.34, 95% confidence interval = 1.07-1.67). Conclusion This study adds to evidence for the effectiveness of incentives to increase response rates to follow-up questionnaires in health intervention trials.

Selective vibration sensing: a new concept for activity-sensing rate-responsive pacing.

PubMed

Lau, C P; Stott, J R; Toff, W D; Zetlein, M B; Ward, D E; Camm, A J

1988-09-01

A clinically available model of an activity-sensing, rate-responsive pacemaker (Activitrax, Medtronic) utilizes body vibration during exercise as an indicator of the need for a rate increase. Although having the advantage of rapid onset of rate response, this system lacks specificity and the rate response does not closely correlate with the level of exertion. In addition, this pacemaker is susceptible to the effects of extraneous vibration. In this study involving 20 normal subjects fitted with an external Activitrax pacemaker, the rate responses to a variety of exercises were studied and were compared with the corresponding sinus rates. The vibration generated at the level of the pacemaker was also measured by accelerometers in three axes. Only a fair correlation (r = 0.51) was achieved between the pacemaker rate and the sinus rate. The total root mean square value of acceleration in either the anteroposterior or the vertical axes was found to have a better correlation (r = 0.8). As the main accelerations during physical activities were in the lower frequency range (0.1-4 Hz), a low-pass filter was used to reduce the influence of extraneous vibration. Selective sensing of the acceleration level may be usefully implemented in an algorithm for activity pacing.

The influence of differential response on decision-making in child protective service agencies.

PubMed

Janczewski, Colleen E

2015-01-01

Differential response (DR) profoundly changes the decision pathways of public child welfare systems, yet little is known about how DR shapes the experiences of children whose reports receive an investigation rather than an alternate response. Using data from the National Child Abuse and Neglect Data System (NCANDS), this study examined the relationship between DR implementation and decision outcomes in neglect cases, as measured by investigation, substantiation, and removal rates in 297 U.S. counties. Multivariate regression models included county-level measures of child poverty and proportions of African American children. Path analyses were also conducted to identify mediating effects of prior decision points and moderating effects of DR on poverty and race's influence on decision outcomes. Results indicate that compared to non-DR counties, those implementing DR have significantly lower investigation and substantiation rates within county populations but higher substantiation rates among investigated cases. Regression models showed significant reductions in removal rates associated with DR implementation, but these effects became insignificant in path models that accounted for mediation effects of previous decision points. Findings also suggest that DR implementation may reduce the positive association between child poverty rates and investigation rates, but additional studies with larger samples are needed to confirm this moderation effect. Two methods of calculating decision outcomes, population- and decision-based enumeration, were used, and policy and research implications of each are discussed. This study demonstrates that despite their inherit complexity, large administrative datasets such as NCANDS can be used to assess the impact of wide-scale system change across jurisdictions. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of clinical response to active drugs and placebo on antipsychotics and mood stabilizers relative efficacy for bipolar depression and mania: A meta-regression analysis.

PubMed

Bartoli, Francesco; Clerici, Massimo; Di Brita, Carmen; Riboldi, Ilaria; Crocamo, Cristina; Carrà, Giuseppe

2018-04-01

Randomised placebo-controlled trials investigating treatments for bipolar disorder have been hampered by wide variations of active drugs and placebo clinical response rates. It is important to estimate whether the active drug or placebo response has a greater influence in determining the relative efficacy of drugs for psychosis (antipsychotics) and relapse prevention (mood stabilisers) for bipolar depression and mania. We identified 53 randomised, placebo-controlled trials assessing antipsychotic or mood stabiliser monotherapy ('active drugs') for bipolar depression or mania. We carried out random-effects meta-regressions, estimating the influence of active drugs and placebo response rates on treatment relative efficacy. Meta-regressions showed that treatment relative efficacy for bipolar mania was influenced by the magnitude of clinical response to active drugs ( p=0.002), but not to placebo ( p=0.60). On the other hand, treatment relative efficacy for bipolar depression was influenced by response to placebo ( p=0.047), but not to active drugs ( p=0.98). Despite several limitations, our unexpected findings showed that antipsychotics / mood stabilisers relative efficacy for bipolar depression seems unrelated to active drugs response rates, depending only on clinical response to placebo. Future research should explore strategies to reduce placebo-related issues in randomised, placebo-controlled trials for bipolar depression.

Nonresponse bias in randomized controlled experiments in criminology: Putting the Queensland Community Engagement Trial (QCET) under a microscope.

PubMed

Antrobus, Emma; Elffers, Henk; White, Gentry; Mazerolle, Lorraine

2013-01-01

The goal of this article is to examine whether or not the results of the Queensland Community Engagement Trial (QCET)-a randomized controlled trial that tested the impact of procedural justice policing on citizen attitudes toward police-were affected by different types of nonresponse bias. We use two methods (Cochrane and Elffers methods) to explore nonresponse bias: First, we assess the impact of the low response rate by examining the effects of nonresponse group differences between the experimental and control conditions and pooled variance under different scenarios. Second, we assess the degree to which item response rates are influenced by the control and experimental conditions. Our analysis of the QCET data suggests that our substantive findings are not influenced by the low response rate in the trial. The results are robust even under extreme conditions, and statistical significance of the results would only be compromised in cases where the pooled variance was much larger for the nonresponse group and the difference between experimental and control conditions was greatly diminished. We also find that there were no biases in the item response rates across the experimental and control conditions. RCTs that involve field survey responses-like QCET-are potentially compromised by low response rates and how item response rates might be influenced by the control or experimental conditions. Our results show that the QCET results were not sensitive to the overall low response rate across the experimental and control conditions and the item response rates were not significantly different across the experimental and control groups. Overall, our analysis suggests that the results of QCET are robust and any biases in the survey responses do not significantly influence the main experimental findings.

Low-dose (10-Gy) total skin electron beam therapy for cutaneous T-cell lymphoma: an open clinical study and pooled data analysis.

PubMed

Kamstrup, Maria R; Gniadecki, Robert; Iversen, Lars; Skov, Lone; Petersen, Peter Meidahl; Loft, Annika; Specht, Lena

2015-05-01

Cutaneous T-cell lymphomas (CTCLs) are dominated by mycosis fungoides (MF) and Sézary syndrome (SS), and durable disease control is a therapeutic challenge. Standard total skin electron beam therapy (TSEBT) is an effective skin-directed therapy, but the possibility of retreatments is limited to 2 to 3 courses in a lifetime due to skin toxicity. This study aimed to determine the clinical effect of low-dose TSEBT in patients with MF and SS. In an open clinical study, 21 patients with MF/SS stages IB to IV were treated with low-dose TSEBT over <2.5 weeks, receiving a total dose of 10 Gy in 10 fractions. Data from 10 of these patients were published previously but were included in the current pooled data analysis. Outcome measures were response rate, duration of response, and toxicity. The overall response rate was 95% with a complete cutaneous response or a very good partial response rate (<1% skin involvement with patches or plaques) documented in 57% of the patients. Median duration of overall cutaneous response was 174 days (5.8 months; range: 60-675 days). TSEBT-related acute adverse events (grade 1 or 2) were observed in 60% of patients. Low-dose (10-Gy) TSEBT offers a high overall response rate and is relatively safe. With this approach, reirradiation at times of relapse or progression is likely to be less toxic than standard dose TSEBT. It remains to be established whether adjuvant and combination treatments can prolong the beneficial effects of low-dose TSEBT. Copyright © 2015 Elsevier Inc. All rights reserved.

Low-Dose (10-Gy) Total Skin Electron Beam Therapy for Cutaneous T-Cell Lymphoma: An Open Clinical Study and Pooled Data Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kamstrup, Maria R., E-mail: mkam0004@bbh.regionh.dk; Gniadecki, Robert; Iversen, Lars

2015-05-01

Purpose: Cutaneous T-cell lymphomas (CTCLs) are dominated by mycosis fungoides (MF) and Sézary syndrome (SS), and durable disease control is a therapeutic challenge. Standard total skin electron beam therapy (TSEBT) is an effective skin-directed therapy, but the possibility of retreatments is limited to 2 to 3 courses in a lifetime due to skin toxicity. This study aimed to determine the clinical effect of low-dose TSEBT in patients with MF and SS. Methods and Materials: In an open clinical study, 21 patients with MF/SS stages IB to IV were treated with low-dose TSEBT over <2.5 weeks, receiving a total dose of 10 Gymore » in 10 fractions. Data from 10 of these patients were published previously but were included in the current pooled data analysis. Outcome measures were response rate, duration of response, and toxicity. Results: The overall response rate was 95% with a complete cutaneous response or a very good partial response rate (<1% skin involvement with patches or plaques) documented in 57% of the patients. Median duration of overall cutaneous response was 174 days (5.8 months; range: 60-675 days). TSEBT-related acute adverse events (grade 1 or 2) were observed in 60% of patients. Conclusions: Low-dose (10-Gy) TSEBT offers a high overall response rate and is relatively safe. With this approach, reirradiation at times of relapse or progression is likely to be less toxic than standard dose TSEBT. It remains to be established whether adjuvant and combination treatments can prolong the beneficial effects of low-dose TSEBT.« less

Effects of age and mild cognitive impairment on the pain response system.

PubMed

Kunz, Miriam; Mylius, Veit; Schepelmann, Karsten; Lautenbacher, Stefan

2009-01-01

Both age and dementia have been shown to have an effect on nociception and pain processing. The question arises whether mild cognitive impairment (MCI), which is thought to be a transitional stage between normal ageing and dementia, is also associated with alterations in pain processing. The aim of the present study was to answer this question by investigating the impact of age and MCI on the pain response system. Forty young subjects, 45 cognitively unimpaired elderly subjects and 42 subjects with MCI were investigated by use of an experimental multi-method approach. The subjects were tested for their subjective (pain ratings), motor (RIII reflex), facial (Facial Action Coding System) and their autonomic (sympathetic skin response and evoked heart rate response) responses to noxious electrical stimulation of the nervus suralis. We found significant group differences in the autonomic responses to noxious stimulation. The sympathetic skin response amplitude was significantly reduced in the cognitively unimpaired elderly subjects compared to younger subjects and to an even greater degree in subjects with MCI. The evoked heart rate response was reduced to a similar degree in both groups of aged subjects. Regression analyses within the two groups of the elderly subjects revealed that age and, in the MCI group, cognitive status were significant predictors of the decrease in autonomic responsiveness to noxious stimulation. Except for the autonomic parameters, no other pain parameter differed between the three groups. The pain response system appeared to be quite unaltered in MCI patients compared to cognitively unimpaired individuals of the same age. Only the sympathetic responsiveness qualified as an indicator of early aging effects as well as of pathophysiology associated with MCI, which both seemed to affect the pain system independently from each other.

Behavioral regulation of gravity - Schedule effects under escape-avoidance procedures

NASA Technical Reports Server (NTRS)

Clark, F. C.; Lange, K. O.; Belleville, R. E.

1973-01-01

Squirrel monkeys were restrained in a centrifuge capsule and trained to escape and avoid increases in artificial gravity. During escape-avoidance, lever responses reduced centrifugally simulated gravity or postponed scheduled increases. The effect of variation in the interval of postponement (equal to the duration of decrease produced by escape responses) was studied under a multiple schedule of four components. Three components were gravity escape-avoidance with postponement times of 20, 40, and 60 sec. The fourth component was extinction. Each component was associated with a different auditory stimulus. Rate of responding decreased with increasing postponement time and higher mean g-levels occurred at shorter intervals of postponement. Effects of the schedule parameter on response rate and mean g-level were similar to effects of the schedule on free-operant avoidance and on titration behavior maintained by shock.

Sound envelope encoding in the auditory cortex revealed by neuromagnetic responses in the theta to gamma frequency bands.

PubMed

Miyazaki, Takahiro; Thompson, Jessica; Fujioka, Takako; Ross, Bernhard

2013-04-19

Amplitude fluctuations of natural sounds carry multiple types of information represented at different time scales, such as syllables and voice pitch in speech. However, it is not well understood how such amplitude fluctuations at different time scales are processed in the brain. In the present study we investigated the effect of the stimulus rate on the cortical evoked responses using magnetoencephalography (MEG). We used a two-tone complex sound, whose envelope fluctuated at the difference frequency and induced an acoustic beat sensation. When the beat rate was continuously swept between 3Hz and 60Hz, auditory evoked response showed distinct transient waves at slow rates, while at fast rates continuous sinusoidal oscillations similar to the auditory steady-state response (ASSR) were observed. We further derived temporal modulation transfer functions (TMTF) from amplitudes of the transient responses and from the ASSR. The results identified two critical rates of 12.5Hz and 25Hz, at which consecutive transient responses overlapped with each other. These stimulus rates roughly corresponded to the rates at which the perceptual quality of the sound envelope is known to change. Low rates (> 10Hz) are perceived as loudness fluctuation, medium rates as acoustical flutter, and rates above 25Hz as roughness. We conclude that these results reflect cortical processes that integrate successive acoustic events at different time scales for extracting complex features of natural sound. Copyright © 2013 Elsevier B.V. All rights reserved.

Increasing response rates to lifestyle surveys: a pragmatic evidence review.

PubMed

McCluskey, S; Topping, A E

2011-03-01

Lifestyle surveys are often a key component of a local Joint Strategic Needs Assessment (JSNA), undertaken to inform public health planning. They are usually administered to a large number of people in order to provide a comprehensive profile of population health. However, declining response rates coupled with the under-representation of certain population groups in lifestyle survey data has led to doubts concerning the reliability of findings. In order to inform the design of their own lifestyle survey, NHS Calderdale commissioned an evidence-based review of the methodological literature relating to the administration of lifestyle surveys, with the specific aim of identifying practical and resource-efficient strategies shown to be effective for maximizing whole-population response rates. A pragmatic review of the published literature was undertaken, specifically to explore the most practical and resource-efficient ways to maximize lifestyle survey response rates to the most commonly used methods (postal surveys, face-to-face interviews, telephone interviews and electronic surveys). Electronic databases including MEDLINE, CINAHL, DARE, EMBASE and PsychINFO were searched. Empirical evidence published in the last 10 years was identified and citation tracking performed on all retrieved articles. An internet search for 'grey literature' was also conducted. The postal questionnaire remains an important lifestyle survey tool, but reported response rates have decreased rapidly in recent years. Interviews and telephone surveys are recommended in order to supplement data from postal questionnaires and increase response rates in some population groups, but costs may be prohibitive. Electronic surveys are a cheaper alternative, but the empirical evidence on effectiveness is inconclusive. Careful planning and tailoring of survey design to the characteristics of target populations can increase response rates and representativeness of lifestyle survey data. The results of this pragmatic review could provide a valuable resource for those involved in the design and administration of lifestyle surveys.

Context Effects in Multi-Alternative Decision Making: Empirical Data and a Bayesian Model

ERIC Educational Resources Information Center

Hawkins, Guy; Brown, Scott D.; Steyvers, Mark; Wagenmakers, Eric-Jan

2012-01-01

For decisions between many alternatives, the benchmark result is Hick's Law: that response time increases log-linearly with the number of choice alternatives. Even when Hick's Law is observed for response times, divergent results have been observed for error rates--sometimes error rates increase with the number of choice alternatives, and…

Equilibration and Sensory Overload in the Pre-School Child: Some Effects of Children's Television Programming.

ERIC Educational Resources Information Center

Miller, Thomas W.

This paper reports an attempt to research sensory overstimulation in a variety of children's television programs by rating the level of visual sensory stimulation, auditory sensory stimulation, verbal response patterns and nonverbal response patterns in 45 television programs designed for pre-school children. The Television Rating Inventory (TVRI)…

Using Norm-Based Appeals to Increase Response Rates in Evaluation Research: A Field Experiment

ERIC Educational Resources Information Center

Misra, Shalini; Stokols, Daniel; Marino, Anne Heberger

2012-01-01

A field experiment was conducted to test the effectiveness of norm-based persuasive messages for increasing response rates in online survey research. Participants in an interdisciplinary conference were asked to complete two successive postconference surveys and randomly assigned to one of two groups at each time point. The experimental group…

Summary of the effects of engine throttle response on airplane formation-flying qualities

NASA Technical Reports Server (NTRS)

Walsh, Kevin R.

1992-01-01

A flight evaluation as conducted to determine the effect of engine throttle response characteristics on precision formation-flying qualities. A variable electronic throttle control system was developed and flight-tested on a TF-104G airplane with a J79-11B engine at the NASA Dryden Flight Research Facility. Ten research flights were flown to evaluate the effects of throttle gain, time delay, and fuel control rate limiting on engine handling qualities during a demanding precision wing formation task. Handling quality effects of lag filters and lead compensation time delays were also evaluated. Data from pilot ratings and comments indicate that throttle control system time delays and rate limits cause significant degradations in handling qualities. Threshold values for satisfactory (level 1) and adequate (level 2) handling qualities of these key variables are presented.

Response deprivation, reinforcement, and economics

PubMed Central

Allison, James

1993-01-01

Reinforcement of an instrumental response results not from a special kind of response consequence known as a reinforcer, but from a special kind of schedule known as a response-deprivation schedule. Under the requirements of a response-deprivation schedule, the baseline rate of the instrumental response permits less than the baseline rate of the contingent response. Because reinforcement occurs only if the schedule deprives the organism of the contingent response, reinforcement cannot result from any intrinsic property of the contingent response or any property relative to the instrumental response. Two typical effects of response-deprivation schedules—facilitation of the instrumental response and suppression of the contingent response—are discussed in terms of economic concepts and models of instrumental performance. It is suggested that response deprivation makes the contingent response function as an economic good, the instrumental response as currency. PMID:16812695

Quantitative Genetic Modeling of the Parental Care Hypothesis for the Evolution of Endothermy

PubMed Central

Bacigalupe, Leonardo D.; Moore, Allen J.; Nespolo, Roberto F.; Rezende, Enrico L.; Bozinovic, Francisco

2017-01-01

There are two heuristic explanations proposed for the evolution of endothermy in vertebrates: a correlated response to selection for stable body temperatures, or as a correlated response to increased activity. Parental care has been suggested as a major driving force in this context given its impact on the parents' activity levels and energy budgets, and in the offspring's growth rates due to food provisioning and controlled incubation temperature. This results in a complex scenario involving multiple traits and transgenerational fitness benefits that can be hard to disentangle, quantify and ultimately test. Here we demonstrate how standard quantitative genetic models of maternal effects can be applied to study the evolution of endothermy, focusing on the interplay between daily energy expenditure (DEE) of the mother and growth rates of the offspring. Our model shows that maternal effects can dramatically exacerbate evolutionary responses to selection in comparison to regular univariate models (breeder's equation). This effect would emerge from indirect selection mediated by maternal effects concomitantly with a positive genetic covariance between DEE and growth rates. The multivariate nature of selection, which could favor a higher DEE, higher growth rates or both, might partly explain how high turnover rates were continuously favored in a self-reinforcing process. Overall, our quantitative genetic analysis provides support for the parental care hypothesis for the evolution of endothermy. We contend that much has to be gained from quantifying maternal and developmental effects on metabolic and thermoregulatory variation during adulthood. PMID:29311952

Application of Statistic Experimental Design to Assess the Effect of Gammairradiation Pre-Treatment on the Drying Characteristics and Qualities of Wheat

NASA Astrophysics Data System (ADS)

Yu, Yong; Wang, Jun

Wheat, pretreated by 60Co gamma irradiation, was dried by hot-air with irradiation dosage 0-3 kGy, drying temperature 40-60 °C, and initial moisture contents 19-25% (drying basis). The drying characteristics and dried qualities of wheat were evaluated based on drying time, average dehydration rate, wet gluten content (WGC), moisture content of wet gluten (MCWG)and titratable acidity (TA). A quadratic rotation-orthogonal composite experimental design, with three variables (at five levels) and five response functions, and analysis method were employed to study the effect of three variables on the individual response functions. The five response functions (drying time, average dehydration rate, WGC, MCWG, TA) correlated with these variables by second order polynomials consisting of linear, quadratic and interaction terms. A high correlation coefficient indicated the suitability of the second order polynomial to predict these response functions. The linear, interaction and quadratic effects of three variables on the five response functions were all studied.

Temperature and Strain-Rate Effects on Low-Cycle Fatigue Behavior of Alloy 800H

NASA Technical Reports Server (NTRS)

Rao, K. Bhanu Sankara; Schiffers, H.; Schuster, H.; Halford, G. R.

1996-01-01

The effects of strain rate (4 x 10(exp -6) to 4 x 10(exp -3)/s) and temperature on the Low-Cycle Fatigue (LCF) behavior of alloy 800H have been evaluated in the range 750 C to 950 C. Total axial strain controlled LCF tests were conducted in air at a strain amplitude of +/- 0.30 pct. LCF life decreased with decreasing strain rate and increasing temperature. The cyclic stress response behavior showed a marked variation with temperature and strain rate. The time- and temperature- dependent processes which influence the cyclic stress response and life have been identified and their relative importance assessed. Dynamic strain aging, time-dependent deformation, precipitation of parallel platelets of M(23)C6 on grain boundaries and incoherent ledges of twins, and oxidation were found to operate depending on the test conditions. The largest effect on life was shown by oxidation processes.

Adrenergic blocker carvedilol attenuates the cardiovascular and aversive effects of nicotine in abstinent smokers.

PubMed

Sofuoglu, Mehmet; Mouratidis, Maria; Yoo, Sonah; Kosten, Thomas

2006-12-01

The cardiovascular response to nicotine is mediated mainly by noradrenergic activation. Whether noradrenergic activation mediates other effects of nicotine has not been well documented in humans. In this study, we examined the effects of an alpha and beta-adrenergic receptor blocker: carvedilol, on cardiovascular and subjective responses to nicotine lozenge and on the ability of nicotine lozenge to suppress tobacco withdrawal symptoms in overnight abstinent smokers. Fifteen smokers, nine men and six women, participated in a double-blind, placebo-controlled, crossover study. In each of the three experimental sessions, participants were treated orally with a single 25 or 50 mg dose of carvedilol or placebo. Two hours and 10 min following the medication treatment, participants received a single 4 mg nicotine lozenge. Carvedilol treatment attenuated the nicotine-induced heart rate, systolic and diastolic blood pressure increases. Carvedilol also attenuated the self-report rating of 'bad effects' in response to nicotine. Carvedilol, alone or in combination with nicotine lozenge, did not affect tobacco withdrawal symptoms. Carvedilol treatment did not affect performance on the Stroop Test. These results support the effectiveness of carvedilol for attenuating the cardiovascular effects of nicotine. Attenuation of the rating of 'bad effects' by carvedilol suggests that noradrenergic activation may also mediate the aversive effects of nicotine.

Immediate Effects of Smoking on Cardiorespiratory Responses During Dynamic Exercise: Arm Vs. Leg Ergometry.

PubMed

Chen, Chien-Liang; Tang, Jing-Shia; Li, Ping-Chia; Chou, Pi-Ling

2015-01-01

This study compared the immediate effects of smoking on cardiorespiratory responses to dynamic arm and leg exercises. This randomized crossover study recruited 14 college students. Each participant underwent two sets of arm-cranking (AC) and leg-cycling (LC) exercise tests. The testing sequences of the control trial (participants refrained from smoking for 8 h before testing) and the experimental trial (participants smoked two cigarettes immediately before testing) were randomly chosen. We observed immediate changes in pulmonary function and heart rate variability after smoking and before the exercise test. The participants then underwent graded exercise tests of their arms and legs until reaching exhaustion. We compared the peak work achieved and time to exhaustion during the exercise tests with various cardiorespiratory indices [i.e., heart rate, oxygen consumption (VO2), minute ventilation (VE)]. The differences between the smoking and control trials were calculated using paired t-tests. For the exercise test periods, VO2, heart rate, and VE values were calculated at every 10% increment of the maximal effort time. The main effects of the time and trial, as well as their trial-by-time (4 × 10) interaction effects on the outcome measures, were investigated using repeated measure ANOVA with trend analysis. 5 min after smoking, the participants exhibited reduced forced vital capacities and forced expiratory volumes in the first second (P < 0.05), in addition to elevated resting heart rates (P < 0.001). The high-frequency, low-frequency, and the total power of the heart rate variability were also reduced (P < 0.05) at rest. For the exercise test periods, smoking reduced the time to exhaustion (P = 0.005) and the ventilatory threshold (P < 0.05) in the LC tests, whereas no significant effects were observed in the AC tests. A trend analysis revealed a significant trial-by-time interaction effect for heart rate, VO2, and VE during the graded exercise test (all P < 0.001). Lower VO2 and VE levels were exhibited in the exercise response of the smoking trial than in those of the control LC trials, whereas no discernable inter-trial difference was observed in the AC trials. Moreover, the differences in heart rate and VE response between the LC and AC exercises were significantly smaller after the participants smoked. This study verified that smoking significantly decreased performance and cardiorespiratory responses to leg exercises. However, the negative effects of smoking on arm exercise performance were not as pronounced.

Additive effects on the energy barrier for synaptic vesicle fusion cause supralinear effects on the vesicle fusion rate

PubMed Central

Schotten, Sebastiaan; Meijer, Marieke; Walter, Alexander Matthias; Huson, Vincent; Mamer, Lauren; Kalogreades, Lawrence; ter Veer, Mirelle; Ruiter, Marvin; Brose, Nils; Rosenmund, Christian

2015-01-01

The energy required to fuse synaptic vesicles with the plasma membrane (‘activation energy’) is considered a major determinant in synaptic efficacy. From reaction rate theory, we predict that a class of modulations exists, which utilize linear modulation of the energy barrier for fusion to achieve supralinear effects on the fusion rate. To test this prediction experimentally, we developed a method to assess the number of releasable vesicles, rate constants for vesicle priming, unpriming, and fusion, and the activation energy for fusion by fitting a vesicle state model to synaptic responses induced by hypertonic solutions. We show that complexinI/II deficiency or phorbol ester stimulation indeed affects responses to hypertonic solution in a supralinear manner. An additive vs multiplicative relationship between activation energy and fusion rate provides a novel explanation for previously observed non-linear effects of genetic/pharmacological perturbations on synaptic transmission and a novel interpretation of the cooperative nature of Ca2+-dependent release. DOI: http://dx.doi.org/10.7554/eLife.05531.001 PMID:25871846

Responding for sucrose and wheel-running reinforcement: effect of D-amphetamine.

PubMed

Belke, T W; Oldford, A C; Forgie, M Y; Beye, J A

2005-07-01

The present study assessed the effect of D-amphetamine on responding maintained by wheel-running and sucrose reinforcement. Six male albino Wistar rats were placed in running wheels and exposed to a fixed-interval 30-s schedule that produced either a drop of 5% sucrose solution or the opportunity to run for 15 s as reinforcing consequences for lever pressing. Each reinforcer type was signaled by a different stimulus. Doses of 0.25, 0.5, 1.0, 1.5, and 3.0 mg/kg D-amphetamine were administered by i.p. injection 20 min prior to a session. As the dose increased, index of curvature values decreased toward zero and rate-dependency plots revealed increases in lower rates early in the interval and decreases in higher rates toward the end of the interval. Effects were similar in the presence of both stimuli. However, an analysis of post-reinforcement pauses and local response rates broken down by transitions revealed a differential effect. As the dose increased, local response rates following a wheel-running reinforcer were affected more than those following a sucrose reinforcer.

Effects of pesticides and antibiotics on penaeid shrimp with special emphases on behavioral and biomarker responses.

PubMed

Tu, Huynh Thi; Silvestre, Frederic; Phuong, Nguyen Thanh; Kestemont, Patrick

2010-04-01

The purpose of the present study is to provide information on the current state of knowledge regarding the effects of pesticides and antibiotics used in aquaculture on penaeid shrimp, one of the most common aquatic products for human consumption, with a special emphasis on the use of behavioral, physiological, and biochemical response. These include behavior; feeding rate changes; respiration rate, oxygen consumption, and osmoregulation alterations; nucleic acids, protein, and glycogen synthesis; cholinesterase activity inhibition; ATPase activity; and oxidative stress responses. This paper also deals with residues of antibiotics and pesticides in penaeid shrimp. Antibiotics and pesticides used in aquaculture may have adverse effects on treated animals and human consumers health if they are not correctly used. As a complement to the measurement of antibiotic and pesticide residues in tissues, the use of behavioral and biomarker responses can provide more relevant biological information on the potential adverse effects of antibiotics and pesticides on penaeid shrimp health. (c) 2009 SETAC.

Continuous aesthetic judgment of image sequences.

PubMed

Khaw, Mel W; Freedberg, David

2018-05-18

Perceptual judgments are said to be reference-dependent as they change on the basis of recent experiences. Here we quantify sequence effects within two types of aesthetic judgments: (i) individual ratings of single images (during self-paced trials) and (ii) continuous ratings of image sequences. As in the case of known contrast effects, trial-by-trial aesthetic responses are negatively correlated with judgments made toward the preceding image. During continuous judgment, a different type of bias is observed. The onset of change within a sequence introduces a persistent increase in ratings (relative to when the same images are judged in isolation). Furthermore, subjects indicate adjustment patterns and choices that selectively favor sequences that are rich in change. Sequence effects in aesthetic judgments thus differ greatly depending on the continuity and arrangement of presented stimuli. The effects highlighted here are important in understanding sustained aesthetic responses over time, such as those elicited during choreographic and musical arrangements. In contrast, standard measurements of aesthetic responses (over trials) may represent a series of distinct aesthetic experiences (e.g., viewing artworks in a museum). Copyright © 2018 Elsevier B.V. All rights reserved.

Citicoline Affects Appetite and Cortico-Limbic Responses to Images of High Calorie Foods

PubMed Central

Killgore, William D. S.; Ross, Amy J.; Kamiya, Toshi; Kawada, Yoko; Renshaw, Perry F.; Yurgelun-Todd, Deborah A.

2011-01-01

Cytidine-5’-diphosphocholine (citicoline) has a variety of cognitive enhancing, neuroprotective, and neuroregenerative properties. In cocaine-addicted individuals, citicoline has been shown to increase brain dopamine levels and reduce cravings. The effects of this compound on appetite, food cravings, and brain responses to food are unknown. We compared the effects of treatment with citicoline (500 mg/day versus 2000 mg/day) for six weeks on changes in appetite ratings, weight, and cortico-limbic responses to images of high calorie foods using functional magnetic resonance imaging (fMRI). After six weeks, there was no significant change in weight status, although significant declines in appetite ratings were observed for the 2000 mg/day group. The higher dose group also showed significant increases in functional brain responses to food stimuli within the amygdala, insula, and lateral orbitofrontal cortex. Increased activation in these regions correlated with declines in appetite ratings. These preliminary findings suggest a potential usefulness of citicoline in modulating appetite, but further research is warranted. PMID:19260039

Modulation of Response Timing in ADHD, Effects of Reinforcement Valence and Magnitude

ERIC Educational Resources Information Center

Luman, Marjolein; Oosterlaan, Jaap; Sergeant, Joseph A.

2008-01-01

The present study investigated the impact of reinforcement valence and magnitude on response timing in children with ADHD. Children were required to estimate a 1-s interval, and both the median response time (response tendency) and the intrasubject-variability (response stability) were investigated. In addition, heart rate and skin conductance…

Contrasting approaches to the response-contingent learning of young children with significant delays and their social-emotional consequences.

PubMed

Dunst, Carl J; Raab, Melinda; Hamby, Deborah W

2017-04-01

The purpose of the analyses described in this paper was to evaluate the direct and indirect effects of two different approaches to child response-contingent learning on rates of child learning and both concomitant and collateral child social-emotional behaviour. The participants were 71 children with significant developmental delays or multiple disabilities randomly assigned to either of the two contrasting approaches to interventions. Findings showed that an intervention which employed practices that built on existing child behaviour (asset-based practices) was more effective than an intervention focusing on teaching children missing skills (needs-based practices) for influencing changes in the rates of child learning as well as rates of child social-emotional behaviour mediated by differences in rates of child learning. Both the theoretical and practical importance of the results are described in terms of the extended social-emotional benefits of asset-based response-contingent learning games. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

The effects of caffeine in women during aerobic-dance bench stepping.

PubMed

Ahrens, Jennifer N; Lloyd, Lisa K; Crixell, Sylvia H; Walker, John L

2007-02-01

People of all ages and fitness levels participate regularly in aerobic-dance bench stepping (ADBS) to increase fitness and control body weight. Any reasonable method for enhancing the experience or effectiveness of ADBS would be beneficial. This study examined the acute effects of a single dose of caffeine on physiological responses during ADBS in women. When compared with a placebo, neither a 3- nor a 6-mg/kg dose of caffeine altered physiological responses or rating of perceived exertion (RPE) in 20 women (age 19-28 y) of average fitness level, not habituated to caffeine, while they performed an ADBS routine. Since neither dose of caffeine had any effect on VO2, VCO2, minute ventilation, respiratory-exchange ratio, rate of energy expenditure, heart rate, or RPE during ADBS exercise, it would not be prudent for a group exercise leader to recommend caffeine to increase energy cost or decrease perception of effort in an ADBS session. Furthermore, caffeine ingestion should not interfere with monitoring intensity using heart rate or RPE during ADBS.

Effect of questionnaire length, personalisation and reminder type on response rate to a complex postal survey: randomised controlled trial

PubMed Central

2011-01-01

Background Minimising participant non-response in postal surveys helps to maximise the generalisability of the inferences made from the data collected. The aim of this study was to examine the effect of questionnaire length, personalisation and reminder type on postal survey response rate and quality and to compare the cost-effectiveness of the alternative survey strategies. Methods In a pilot study for a population study of travel behaviour, physical activity and the environment, 1000 participants sampled from the UK edited electoral register were randomly allocated using a 2 × 2 factorial design to receive one of four survey packs: a personally addressed long (24 page) questionnaire pack, a personally addressed short (15 page) questionnaire pack, a non-personally addressed long questionnaire pack or a non-personally addressed short questionnaire pack. Those who did not return a questionnaire were stratified by initial randomisation group and further randomised to receive either a full reminder pack or a reminder postcard. The effects of the survey design factors on response were examined using multivariate logistic regression. Results An overall response rate of 17% was achieved. Participants who received the short version of the questionnaire were more likely to respond (OR = 1.48, 95% CI 1.06 to 2.07). In those participants who received a reminder, personalisation of the survey pack and reminder also increased the odds of response (OR = 1.44, 95% CI 1.01 to 1.95). Item non-response was relatively low, but was significantly higher in the long questionnaire than the short (9.8% vs 5.8%; p = .04). The cost per additional usable questionnaire returned of issuing the reminder packs was £23.1 compared with £11.3 for the reminder postcards. Conclusions In contrast to some previous studies of shorter questionnaires, this trial found that shortening a relatively lengthy questionnaire significantly increased the response. Researchers should consider the trade off between the value of additional questions and a larger sample. If low response rates are expected, personalisation may be an important strategy to apply. Sending a full reminder pack to non-respondents appears a worthwhile, albeit more costly, strategy. PMID:21548947

Efficacy and influence factors of icotinib hydrochloride in treating advanced non-small cell lung cancer.

PubMed

Ma, X-H; Tian, T-D; Liu, H-M; Li, Q-J; Gao, Q-L; Li, L; Shi, B

2017-01-01

To evaluate the efficacy and safety of icotinib hydrochloride in the treatment of patients with advanced non-small cell lung cancer (NSCLC) and discuss the influence factors on efficacy. 120 treatment-experienced patients confirmed by pathology or cytology with stage III B-IV non-small cell lung cancer took icotinib hydrochloride and erlotinib orally until the occurrence of disease progression or serious adverse reactions. Then, the efficacy of icotinib hydrochloride and the related influence factors were analyzed. In icotinib hydrochloride group, the response rate and the disease control rate were 30.00% and 65.00%, and the median progression-free survival time was 179 days (95% CI: 103.21-254.78); in erlotinib group, the response rate and the disease control rate were 25.00% and 56.70%, and the median progression-free survival time was 121 days (95% CI: 95.05-146.94). Moreover, the objective response rate and the disease control rate of second-line therapy were both superior to the third-line and above therapy. The objective response rate of patients with complete response/partial response/stable disease after the first-line therapy was higher than that of patients without response after the first-line therapy (p<0.05), and the significant differences existed in the objective response rate and the disease control rate among mutant group, wild-type group, and unknown group (p<0.05). The response rate and the disease control rate of erythra group were higher than those of non-erythra group (p<0.05). It was showed in the univariate analysis that the progression-free survival was correlated with the smoking status and the epidermal growth factor receptor gene mutations. The icotinib hydrochloride is effective and safe in treating the treatment-experienced patients with advanced NSCLC, especially for patients with sensitive mutations.

Impact of response shift on the assessment of treatment effects using the Oral Health Impact Profile.

PubMed

Reissmann, Daniel R; Remmler, Antje; John, Mike T; Schierz, Oliver; Hirsch, Christian

2012-12-01

The assessment of changes in oral health-related quality of life (OHRQoL) is challenging because individuals' concepts and internal standards of OHRQoL may change over time. The aim of this study was to detect response shifts in OHRQoL assessments made using the Oral Health Impact Profile (OHIP). Oral health-related quality of life was assessed in a consecutive sample of 126 patients seeking prosthodontic care. Patients were asked to rate their OHRQoL before treatment started and 1 month after treatment was finished, using the German 49-item version of the OHIP. When rating their OHRQoL after treatment, patients were also asked to rate their pre-treatment OHRQoL without having access to their baseline data. The response shift was calculated as the difference in OHIP summary scores between the initial assessment and the retrospective baseline assessment. The OHIP mean scores decreased from 31.8 at the initial baseline assessment to 24.4 after treatment. The retrospective baseline assessment resulted in an OHIP mean score of 38.1, corresponding to a response shift of 6.3 OHIP points. The effect size (Cohen's d = 0.21) of the response shift was considered small. The response shift phenomenon and its magnitude have important implications for dental practice, where patients and dentists often assess perceived treatment effects retrospectively. © 2012 Eur J Oral Sci.

Treatment of comorbid anxiety and depression with escitalopram: results of a post-marketing surveillance study.

PubMed

Laux, G; Friede, M; Müller, W E

2013-01-01

In this 16-week post-marketing surveillance (PMS) study, antidepressant effects and tolerability of escitalopram was examined in 2 911 patients with comorbid depression and anxiety. Antidepressant effects were assessed using a modified version of the Montgomery-Åsberg depression rating scale (svMADRS), the Hamilton anxiety scale (HAMA) and the hospital anxiety depression scale (HADS-D) and the clinical global impression scale (CGI-S, CGI-I). Treatment was completed by 2 718 patients, whose severity of depression decreased from a mean svMADRS total score of 33.0 to 8.9. At the end of the study, the remission rate (svMADRS≤12) was 72.9% and the response rate (≥50% decrease in svMADRS score) was 83.1% (LOCF). Similarly, the severity of anxiety symptoms decreased from a mean HAMA total score of 28.8-8.8; the remission rate (HAMA<10) was 63.9% and the response rate (decrease≥50%) was 80.2%. The most frequent adverse events were nausea (1.6%), agitation (1.1%) and fatigue (0.7%). Antidepressant effects and good tolerability of escitalopram were confirmed in everyday practice in patients with comorbid depression and anxiety. The high response and remission rates were within the range reported in previous RTC's of escitalopram vs. comparators or vs. placebo. © Georg Thieme Verlag KG Stuttgart · New York.

Probing topology by "heating": Quantized circular dichroism in ultracold atoms.

PubMed

Tran, Duc Thanh; Dauphin, Alexandre; Grushin, Adolfo G; Zoller, Peter; Goldman, Nathan

2017-08-01

We reveal an intriguing manifestation of topology, which appears in the depletion rate of topological states of matter in response to an external drive. This phenomenon is presented by analyzing the response of a generic two-dimensional (2D) Chern insulator subjected to a circular time-periodic perturbation. Because of the system's chiral nature, the depletion rate is shown to depend on the orientation of the circular shake; taking the difference between the rates obtained from two opposite orientations of the drive, and integrating over a proper drive-frequency range, provides a direct measure of the topological Chern number (ν) of the populated band: This "differential integrated rate" is directly related to the strength of the driving field through the quantized coefficient η 0 = ν/ ℏ 2 , where h = 2π ℏ is Planck's constant. Contrary to the integer quantum Hall effect, this quantized response is found to be nonlinear with respect to the strength of the driving field, and it explicitly involves interband transitions. We investigate the possibility of probing this phenomenon in ultracold gases and highlight the crucial role played by edge states in this effect. We extend our results to 3D lattices, establishing a link between depletion rates and the nonlinear photogalvanic effect predicted for Weyl semimetals. The quantized circular dichroism revealed in this work designates depletion rate measurements as a universal probe for topological order in quantum matter.

Combined local and systemic bleomycin administration in electrochemotherapy to reduce the number of treatment sessions

PubMed Central

Tellado, Matias; Olaiz, Nahuel; Michinski, Sebastian; Marshall, Guillermo

2016-01-01

Background Electrochemotherapy (ECT), a medical treatment widely used in human patients for tumor treatment, increases bleomycin toxicity by 1000 fold in the treated area with an objective response rate of around 80%. Despite its high response rate, there are still 20% of cases in which the patients are not responding. This could be ascribed to the fact that bleomycin, when administered systemically, is not reaching the whole tumor mass properly because of the characteristics of tumor vascularization, in which case local administration could cover areas that are unreachable by systemic administration. Patients and methods We propose combined bleomycin administration, both systemic and local, using companion animals as models. We selected 22 canine patients which failed to achieve a complete response after an ECT treatment session. Eleven underwent another standard ECT session (control group), while 11 received a combined local and systemic administration of bleomycin in the second treatment session. Results According to the WHO criteria, the response rates in the combined administration group were: complete response (CR) 54% (6), partial response (PR) 36% (4), stable disease (SD) 10% (1). In the control group, these were: CR 0% (0), PR 19% (2), SD 63% (7), progressive disease (PD) 18% (2). In the combined group 91% objective responses (CR+PR) were obtained. In the control group 19% objective responses were obtained. The difference in the response rate between the treatment groups was significant (p < 0.01). Conclusions Combined local and systemic bleomycin administration was effective in previously to ECT non responding canine patients. The results indicate that this approach could be useful and effective in specific population of patients and reduce the number of treatment sessions needed to obtain an objective response. PMID:27069450

Disruption of the auditory response to a regular click train by a single, extra click.

PubMed

Lütkenhöner, Bernd; Patterson, Roy D

2015-06-01

It has been hypothesized that the steady-state response to a periodic sequence of clicks can be modeled as the superposition of responses to single clicks. Here, this hypothesis is challenged by presenting an extra click halfway between two consecutive clicks of a regular series, while measuring the auditory evoked field. After a solitary click at time zero, the click series sounded from 100 to 900 ms, with the extra click presented around 500 ms. The silent period between two stimulus sequences was 310-390 ms (uniformly distributed) so that one stimulation cycle lasted, on average, 1250 ms. Five different click rates between 20 and 60 Hz were examined. The disturbance caused by the extra click was revealed by subtracting the estimated steady-state response from the joint response to the click series and the extra click. The early peaks of the single-click response effectively coincide with same-polarity peaks of the 20-Hz steady-state response. Nevertheless, prediction of the latter from the former proved impossible. However, the 40-Hz steady-state response can be predicted reasonably well from the 20-Hz steady-state response. Somewhat surprisingly, the amplitude of the evoked response to the extra click grew when the click rate of the train was increased from 20 to 30 Hz; the opposite effect would have been expected from research on adaptation. The smaller amplitude at lower click rates might be explained by forward suppression. In this case, the apparent escape from suppression at higher rates might indicate that the clicks belonging to the periodic train are being integrated into an auditory stream, possibly in much the same manner as in classical stream segregation experiments.

Lights … action: Comparison of trauma films for use in the trauma film paradigm.

PubMed

Arnaudova, Inna; Hagenaars, Muriel A

2017-06-01

Affective films are often used in emotion research and negative films are frequently used as an analogue for trauma (trauma film paradigm). However, different films are used with possibly distinct consequences. We aimed to investigate specific effects of four negative films covering distinct themes (physical, sexual, traffic and food), and tested neutral and positive films with matching content. Self-reported emotional responses and heart rate during the films were examined (immediate responses) as well as intrusions of the films in the subsequent week (delayed responses). Within each theme, negative films were rated as more unpleasant than the positive and neutral counterparts. They also evoked more negative emotions and more intrusive memories. Across themes, the four negative films did not differ in terms of valence and arousal, but clearly differed on immediate (e.g., disgust, embarrassment, heart rate) and delayed (intrusions) effects. Thus, we urge researchers to carefully select negative films for their studies, as different films seem to evoke distinct emotional responses. In addition, using positive films within the same themes is recommended in order to control for effects of arousal. In general, the specific film material should be considered when comparing effects across studies. Copyright © 2017 Elsevier Ltd. All rights reserved.

The modulatory effects of noradrenaline on vagal control of heart rate in the dogfish, Squalus acanthias.

PubMed

Agnisola, Claudio; Randall, David J; Taylor, Edwin W

2003-01-01

The possible interactions between inhibitory vagal control of the heart and circulating levels of catecholamines in dogfish (Squalus acanthias) were studied using an in situ preparation of the heart, which retained intact its innervation from centrally cut vagus nerves. The response to peripheral vagal stimulation typically consisted of an initial cardiac arrest, followed by an escape beat, leading to renewed beating at a mean heart rate lower than the prestimulation rate (partial recovery). Cessation of vagal stimulation led to a transient increase in heart rate, above the prestimulation rate. This whole response was completely abolished by 10(-4) M atropine (a muscarinic cholinergic antagonist). The degree of vagal inhibition was evaluated in terms of both the initial, maximal cardiac interval and the mean heart rate during partial recovery, both expressed as a percentage of the prestimulation heart rate. The mean prestimulation heart rate of this preparation (36+/-4 beats min(-1)) was not affected by noradrenaline but was significantly reduced by 10(-4) M nadolol (a beta-adrenergic receptor antagonist), suggesting the existence of a resting adrenergic tone arising from endogenous catecholamines. The degree of vagal inhibition of heart rate varied with the rate of stimulation and was increased by the presence of 10(-8) M noradrenaline (the normal in vivo level in routinely active fish), while 10(-7) M noradrenaline (the in vivo level measured in disturbed or deeply hypoxic fish) reduced the cardiac response to vagal stimulation. In the presence of 10(-7) M noradrenaline, 10(-4) M nadolol further reduced the vagal response, while 10(-4) M nadolol + 10(-4) M phentolamine had no effect, indicating a complex interaction between adrenoreceptors, possibly involving presynaptic modulation of vagal inhibition.

Fluvoxamine effects on concurrent ethanol- and food-maintained behaviors

PubMed Central

Ginsburg, Brett C.; Lamb, R.J.

2011-01-01

In previous studies, the selective serotonin reuptake inhibitor fluvoxamine preferentially reduced responding for ethanol compared with responding for food under conditions in which each was available alone in separate groups or in the same subjects under a multiple schedule in which baseline response rates were matched. The impact of providing concurrent access to food on pharmacological effects on ethanol self-administration remains largely unexplored. In this study, acute doses of fluvoxamine (3.0-17.8 mg/kg) were administered 30-min before the experimental session to Lewis rats responding under a concurrent fixed-ratio, fixed-ratio schedule of ethanol and food presentation. Ratios for food were adjusted for each subject to provide matched rates of food and ethanol reinforcement across the 30-min session. Although the number of ethanol and food deliveries did not significantly differ under baseline conditions, response rates did differ. Following fluvoxamine administration, responding for food was decreased more than responding for ethanol. This differential effect did not appear to be related to response rate or fixed-ratio size. Thus, the selectivity of fluvoxamine on ethanol- versus food-maintained responding depends upon the context in which the behavior occurs. Such results may help explain inconsistencies between preclinical results and those in humans, and could provide insight into the behavioral determinants of pharmacological effects on ethanol self-administration. PMID:17115876

Angiotensin II in the paraventricular nucleus stimulates sympathetic outflow to the cardiovascular system and make vasopressin release in rat.

PubMed

Khanmoradi, Mehrangiz; Nasimi, Ali

2016-10-06

The hypothalamic paraventricular nucleus (PVN) plays essential roles in neuroendocrine and autonomic functions, including cardiovascular regulation. It was shown that microinjection of angiotensin II (AngII) into the PVN produced a pressor response. In this study, we explored the probable mechanisms of this pressor response. AngII was microinjected into the PVN and cardiovascular responses were recorded. Then, the responses were re-tested after systemic injection of a ganglionic blocker, Hexamethonium, or a vasopressin V1 receptor blocker. Hexamethonium pretreatment (i.v.) greatly and significantly attenuated the pressor response to AngII, with no significant effect on heart rate, indicating that the sympathetic system is involved in the cardiovascular effect of AngII in the PVN. Systemic pretreatment (i.v.) with V1 antagonist greatly and significantly attenuated the pressor response to AngII, with no significant effect on heart rate, indicating that vasopressin release is involved in the cardiovascular effect of AngII in the PVN. Overall, we found that AngII microinjected into the PVN produced a pressor response mediated by the sympathetic system and vasopressin release, indicating that other than circulating AngII, endogenous AngII of the PVN increases the vasopressin release from the PVN. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Functional response of wolves preying on barren-ground caribou in a multiple-prey ecosystem

USGS Publications Warehouse

Dale, B.W.; Adams, Layne G.; Bowyer, R.T.

1994-01-01

1. We investigated the functional response of wolves (Canis lupus) to varying abundance of ungulate prey to test the hypothesis that switching from alternate prey to preferred prey results in regulation of a caribou (Rangifer tarandus) population at low densities. 2. We determined prey selection, kill rates, and prey abundance for four wolf packs during three 30-day periods in March 1989, March 1990, November 1990, and created a simple discrete model to evaluate the potential for the expected numerical and observed functional responses of wolves to regulate caribou populations. 3. We observed a quickly decelerating type II functional response that, in the absence of numerical response, implicates an anti-regulatory effect of wolf predation on barren-ground caribou dynamics. 4. There was little potential for regulation caused by the multiplicative effect of increasing functional and numerical responses because of presence of alternative prey. This resulted in high wolf:caribou ratios at low prey densities which precluded the effects of an increasing functional response. 5. Inversely density-dependent predation by other predators, such as bears, reduces the potential for predators to regulate caribou populations at low densities, and small reductions in predation by one predator may have disproportionately large effects on the total predation rate.

Effects of voluntary wheel running on heart rate, body temperature, and locomotor activity in response to acute and repeated stressor exposures in rats.

PubMed

Masini, Cher V; Nyhuis, Tara J; Sasse, Sarah K; Day, Heidi E W; Campeau, Serge

2011-05-01

Stress often negatively impacts physical and mental health but it has been suggested that voluntary physical activity may benefit health by reducing some of the effects of stress. The present experiments tested whether voluntary exercise can reduce heart rate, core body temperature and locomotor activity responses to acute (novelty or loud noise) or repeated stress (loud noise). After 6 weeks of running-wheel access, rats exposed to a novel environment had reduced heart rate, core body temperature, and locomotor activity responses compared to rats housed under sedentary conditions. In contrast, none of these measures were different between exercised and sedentary rats following acute 30-min noise exposures, at either 85 or 98 dB. Following 10 weeks of running-wheel access, both groups displayed significant habituation of all these responses to 10 consecutive daily 30-min presentations of 98 dB noise stress. However, the extent of habituation of all three responses was significantly enhanced in exercised compared to sedentary animals on the last exposure to noise. These results suggest that in physically active animals, under some conditions, acute responses to stress exposure may be reduced, and response habituation to repeated stress may be enhanced, which ultimately may reduce the negative and cumulative impact of stress.

Effects of voluntary wheel running on heart rate, body temperature, and locomotor activity in response to acute and repeated stressor exposures in rats

PubMed Central

MASINI, CHER V.; NYHUIS, TARA J.; SASSE, SARAH K.; DAY, HEIDI E. W.; CAMPEAU, SERGE

2015-01-01

Stress often negatively impacts physical and mental health but it has been suggested that voluntary physical activity may benefit health by reducing some of the effects of stress. The present experiments tested whether voluntary exercise can reduce heart rate, core body temperature and locomotor activity responses to acute (novelty or loud noise) or repeated stress (loud noise). After 6 weeks of running-wheel access, rats exposed to a novel environment had reduced heart rate, core body temperature, and locomotor activity responses compared to rats housed under sedentary conditions. In contrast, none of these measures were different between exercised and sedentary rats following acute 30-min noise exposures, at either 85 or 98 dB. Following 10 weeks of running-wheel access, both groups displayed significant habituation of all these responses to 10 consecutive daily 30-min presentations of 98 dB noise stress. However, the extent of habituation of all three responses was significantly enhanced in exercised compared to sedentary animals on the last exposure to noise. These results suggest that in physically active animals, under some conditions, acute responses to stress exposure may be reduced, and response habituation to repeated stress may be enhanced, which ultimately may reduce the negative and cumulative impact of stress. PMID:21438772

'Ecstasy' as a social drug: MDMA preferentially affects responses to emotional stimuli with social content.

PubMed

Wardle, Margaret C; Kirkpatrick, Matthew G; de Wit, Harriet

2014-08-01

3,4-Methylenedioxymethamphetamine (MDMA, 'ecstasy') is used recreationally to improve mood and sociability, and has generated clinical interest as a possible adjunct to psychotherapy. One way that MDMA may produce positive 'prosocial' effects is by changing responses to emotional stimuli, especially stimuli with social content. Here, we examined for the first time how MDMA affects subjective responses to positive, negative and neutral emotional pictures with and without social content. We hypothesized that MDMA would dose-dependently increase reactivity to positive emotional stimuli and dampen reactivity to negative stimuli, and that these effects would be most pronounced for pictures with people in them. The data were obtained from two studies using similar designs with healthy occasional MDMA users (total N = 101). During each session, participants received MDMA (0, 0.75 and 1.5 mg/kg oral), and then rated their positive and negative responses to standardized positive, negative and neutral pictures with and without social content. MDMA increased positive ratings of positive social pictures, but reduced positive ratings of non-social positive pictures. We speculate this 'socially selective' effect contributes to the prosocial effects of MDMA by increasing the comparative value of social contact and closeness with others. This effect may also contribute to its attractiveness to recreational users. © The Author (2014). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

Interactions between imidazoline I2 receptor ligands and acetaminophen in adult male rats: antinociception and schedule-controlled responding

PubMed Central

Siemian, Justin N.; Li, Jiuzhou; Zhang, Yanan; Li, Jun-Xu

2015-01-01

Rationale Recent evidence suggests that imidazoline I2 receptor ligands are suitable for combination therapy with opioids. Quantitative analysis of I2 receptor ligands combined with non-opioid drugs is necessary for justification of alternative pain therapies. Objective This study systematically examined the anti-hyperalgesic and response rate-suppressing effects of selective I2 receptor ligands (2-BFI and phenyzoline) alone and in combination with acetaminophen. Methods Von Frey and Hargreaves tests were used to examine the anti-hyperalgesic effects of drugs in complete Freund’s adjuvant (CFA)-induced inflammatory pain in rats. Food-reinforced schedule-controlled responding was used to assess the rate-suppressing effects of study drugs. Dose-addition and isobolographic analyses were used to assess drug-drug interactions for all assays. Results 2-BFI (3.2–17.8 mg/kg, i.p.), phenyzoline (17.8–100 mg/kg, i.p.), and acetaminophen (56–178 mg/kg, i.p.) all dose-dependently produced significant antinociceptive effects. When studied as combinations, 2-BFI and acetaminophen produced infra-additive to additive interactions while phenyzoline and acetaminophen produced additive to supra-additive interactions. The same drug combinations suppressed response rate in a supra-additive manner. Conclusions Quantitative analysis of the anti-hyperalgesic and response rate-suppressing effects suggests that I2 receptor ligands are not well suited to combination therapy with acetaminophen. PMID:26613734

Margin Status Remains an Important Determinant of Survival after Surgical Resection of Colorectal Liver Metastases in the Era of Modern Chemotherapy

PubMed Central

Andreou, Andreas; Aloia, Thomas A.; Brouquet, Antoine; Dickson, Paxton V.; Zimmitti, Giuseppe; Maru, Dipen M.; Kopetz, Scott; Loyer, Evelyne M.; Curley, Steven A.; Abdalla, Eddie K.; Vauthey, Jean-Nicolas

2013-01-01

Objective To determine the impact of surgical margin status on overall survival (OS) of patients undergoing hepatectomy for colorectal liver metastases (CLM) after modern preoperative chemotherapy. Summary Background Data In the era of effective chemotherapy for CLM, the association between surgical margin status and survival has become controversial. Methods Clinicopathologic data and outcomes for 378 patients treated with modern preoperative chemotherapy and hepatectomy were analyzed. The effect of positive margins on OS was analyzed in relation to pathologic and computed tomography-based morphologic response to chemotherapy. Results Fifty-two of 378 resections (14%) were R1 resections (tumor-free margin < 1 mm). The 5-year OS rates for patients with R0 resection (margin ≥ 1 mm) and R1 resection were 55% and 26%, respectively (P=0.017). Multivariate analysis identified R1 resection (P=0.03) and minor pathologic response to chemotherapy (P=0.002) as the 2 factors independently associated with worse survival. The survival benefit associated with negative margins (R0 vs. R1 resection) was greater in patients with suboptimal morphologic response (5-year OS rate: 62% vs. 11%, P=0.007) than in patients with optimal response (3-year OS rate: 92% vs. 88%, P=0.917) and greater in patients with minor pathologic response (5-year OS rate: 46% vs. 0%, P=0.002) than in patients with major response (5-year OS rate: 63% vs. 67%, P=0.587). Conclusions In the era of modern chemotherapy, negative margins remain an important determinant of survival and should be the primary goal of surgical therapy. The impact of positive margins is most pronounced in patients with suboptimal response to systemic therapy. PMID:23426338

Margin status remains an important determinant of survival after surgical resection of colorectal liver metastases in the era of modern chemotherapy.

PubMed

Andreou, Andreas; Aloia, Thomas A; Brouquet, Antoine; Dickson, Paxton V; Zimmitti, Giuseppe; Maru, Dipen M; Kopetz, Scott; Loyer, Evelyne M; Curley, Steven A; Abdalla, Eddie K; Vauthey, Jean-Nicolas

2013-06-01

To determine the impact of surgical margin status on overall survival (OS) of patients undergoing hepatectomy for colorectal liver metastases after modern preoperative chemotherapy. In the era of effective chemotherapy for colorectal liver metastases, the association between surgical margin status and survival has become controversial. Clinicopathologic data and outcomes for 378 patients treated with modern preoperative chemotherapy and hepatectomy were analyzed. The effect of positive margins on OS was analyzed in relation to pathologic and computed tomography-based morphologic response to chemotherapy. Fifty-two of 378 resections (14%) were R1 resections (tumor-free margin <1 mm). The 5-year OS rates for patients with R0 resection (margin ≥1 mm) and R1 resection were 55% and 26%, respectively (P = 0.017). Multivariate analysis identified R1 resection (P = 0.03) and a minor pathologic response to chemotherapy (P = 0.002) as the 2 factors independently associated with worse survival. The survival benefit associated with negative margins (R0 vs R1 resection) was greater in patients with suboptimal morphologic response (5-year OS rate: 62% vs 11%; P = 0.007) than in patients with optimal response (3-year OS rate: 92% vs 88%; P = 0.917) and greater in patients with a minor pathologic response (5-year OS rate: 46% vs 0%; P = 0.002) than in patients with a major response (5-year OS rate: 63% vs 67%; P = 0.587). In the era of modern chemotherapy, negative margins remain an important determinant of survival and should be the primary goal of surgical therapy. The impact of positive margins is most pronounced in patients with suboptimal response to systemic therapy.

Selective Catalytic Combustion Sensors for Reactive Organic Analysis

NASA Technical Reports Server (NTRS)

Innes, W. B.

1971-01-01

Sensors involving a vanadia-alumina catalyst bed-thermocouple assembly satisfy requirements for simple, reproducible and rapid continuous analysis or reactive organics. Responses generally increase with temperature to 400 C and increase to a maximum with flow rate/catalyst volume. Selectivity decreases with temperature. Response time decreases with flow rate and increases with catalyst volume. At chosen optimum conditions calculated response which is additive and linear agrees better with photochemical reactivity than other methods for various automotive sources, and response to vehicle exhaust is insensitive to flow rate. Application to measurement of total reactive organics in vehicle exhaust as well as for gas chromatography detection illustrate utility. The approach appears generally applicable to high thermal effect reactions involving first order kinetics.

Children’s positive dispositional attributes, parents’ empathic responses, and children’s responses to painful pediatric oncology treatment procedures

PubMed Central

Harper, Felicity W. K.; Penner, Louis A.; Peterson, Amy; Albrecht, Terrance L.; Taub, Jeffrey

2012-01-01

Pain/distress during pediatric cancer treatments has substantial psychosocial consequences for children and families. We examined relationships between children’s positive dispositional attributes, parents’ empathic responses, and children’s pain/distress responses to treatment procedures. Participants were 41 pediatric cancer patients and parents. Several weeks before treatment, parents rated children’s resilience and positive dimensions of temperament. Parents’ pre-treatment empathic affective responses to their children were assessed. Children’s pain/distress during treatments was rated by multiple independent raters. Children’s resilience was significantly and positively associated with parents’ empathic affective responses and negatively associated with children’s pain/distress. Children’s adaptability and attention focusing also showed positive relationships (p<.10) with parents’ empathic responses. Parents’ empathic responses mediated effects of children’s resilience on children’s pain/distress. Children’s positive dispositional attributes influence their pain/distress during cancer treatments; however, these effects may be mediated by parents’ empathic responses. These relationships provide critical understanding of the influence of parent-child relationships on coping with treatment. PMID:22963185

[Effect of interferon and ribavirin combination therapy in sixty-two patients with chronic hepatitis C originating from a single blood donor].

PubMed

Liu, San-du; Cheng, Ming-liang; Ren, Hong; Yang, Qing-kun; Shu, De-yun

2012-08-01

To investigate the efficacy of interferon alpha 2 b plus ribavirin combination therapy in sixty-two patients with chronic hepatitis c (CHC) infection originating from a single blood donor. The 62 patients who developed CHC following blood transfusion from a known single infected donor were treated with interferon and ribavirin combination therapy for 48 weeks and followed-up for 96 weeks. The therapy regimen consisted of subcutaneous administration of 3-500 MIU interferon alpha 2 b every other day and daily oral administration of 0.6-1.0 g of ribavirin. Patients were monitored during treatment and in follow-up for sustained virological response (SVR), early virology response (EVR), treatment end virology response (ETVR), biochemical response of withdrawals, and side effects. The SVR rate was 83.9% (52/62). The EVR rate was 95.2% (59/62). The ETVR rate was 87.1% (54/62). The biochemical response rate after withdrawal of treatment was 100.0%. Eight patients developed mildly abnormal thyroid function as a result of the interferon therapy, but all were able to complete the antiviral treatment regimen under the care of endocrinologists. Younger age, relatively short course of disease, low viral load, and better compliance, but not sex, were correlated to curative effect of the combination therapy. Interferon alpha 2 b plus ribavirin combination therapy had a significant curative effect on a group of 62 CHC patients originating from a single case, with 52 of the patients showing SVR out to 96 weeks after therapy. Antiviral treatment is recommended for hepatitis C virus-positive patients to eradicate the virus and prevent disease progression.

Testing the linearity and independence assumptions of the generalized matching law for reinforcer magnitude: a residual meta-analysis.

PubMed

Cording, Jacinta R; McLean, Anthony P; Grace, Randolph C

2011-05-01

We conducted a residual meta-analysis to test the assumptions of the generalized matching law that effects of relative reinforcer magnitude on response allocation in concurrent schedules can be described by a power function and are independent from the effects of relative reinforcer rate. We identified five studies which varied magnitude ratios over at least four levels and six studies in which reinforcer rate and magnitude ratios were varied factorially. The generalized matching law provided a reasonably good description of the data, accounting for 77.1% and 90.1% of the variance in the two sets of studies. Results of polynomial regressions showed that there were no systematic patterns in pooled residuals as a function of predicted log response ratios for data sets in which relative magnitude was varied. For data sets in which relative rate and magnitude were varied factorially, there was a significant negative cubic pattern in the pooled residuals, suggesting that obtained response allocation was less extreme than predicted for conditions with extreme predicted values. However, subsequent analyses showed that this result was associated with results from conditions in one study in which the product of the rate and magnitude ratios was 63:1, and in which response allocation may have been attenuated by a ceiling effect. When data from these conditions were omitted, there were no significant components in the residuals. Although the number of available studies was small, results provide tentative support for the assumptions of the generalized matching law that effects of reinforcer magnitude ratios on choice can be described by a power function and are independent from reinforcer rate ratios. Copyright © 2011 Elsevier B.V. All rights reserved.

The use of statins for the treatment of depression in patients with acute coronary syndrome

PubMed Central

Kim, S W; Bae, K Y; Kim, J M; Shin, I S; Hong, Y J; Ahn, Y; Jeong, M H; Berk, M; Yoon, J S

2015-01-01

This study aimed to investigate the effect of statins for the treatment of depression in individuals with acute coronary syndrome (ACS). We used 1-year follow-up data of a 24-week double-blind, placebo-controlled trial of escitalopram and a naturalistic prospective observational cohort study. Of 446 participants with comorbid depressive disorders and ACS at baseline, 300 participated in a randomised escitalopram trial and the remaining 146 participated in a naturalistic observational study. The participants in the two studies were approached for a 1-year follow-up investigation. Treatment response rates, defined as a ⩾50% reduction in the Hamilton Depression Rating Scale (HAM-D) and Beck Depression Inventory (BDI) scores, were used as the outcome variables. In the escitalopram trial, both HAM-D and BDI response rates were highest in patients taking escitalopram and statins together and lowest in patients receiving neither medication. Logistic regression analyses revealed that statin use was significantly associated with higher response rates on both the HAM-D and BDI at 1 year, whereas no such associations were found for escitalopram. In the naturalistic observational study, the response rates at 1 year did not differ significantly by statin use. Instead, the HAM-D response rate was significantly higher in patients taking lipophilic statins than in those who did not. In conclusion, statins may be effective for the treatment of depression independent of medical status and escitalopram use, and they may potentiate the antidepressant action of serotonergic antidepressants in patients with ACS. PMID:26285130

Demographic Responses To Climate Manipulations Across a Species Range

NASA Astrophysics Data System (ADS)

Oldfather, M. F.

2016-12-01

Species biogeographic responses to climate change will occur through the local extinction and establishment of populations. The overall performance of populations across a species range is shaped by the idiosyncratic sensitivities of demographic rates to the changing climate conditions. Heterogeneous topography partially decouples temperature and soil moisture presenting an opportunity to disentangle demographic sensitivity to multiple local climate variables and refine range shift predictions in response to complex climate change. Since 2013, I have monitored 16 populations of a long-lived alpine plant, Ivesia lycopodioides var. scandularis (Rosaceae) across the entirety of its altitudinal range in the arid White Mountains, CA (3350 - 4420m). I quantified microclimatic soil moisture and temperature, and the demographic rates of over 4,000 individuals. Demographic rates exhibited sensitivity to accumulated degree-days (ex. reproduction), soil volumetric water content (ex. germination), or the interaction between these climate variables (ex. survival). These observations motivated an experimental test of the relationship between demography and local climate with manipulations of increased summertime temperature and precipitation in nine populations. All demographic rates were sensitive to the climate manipulations and the magnitude of the demographic response depended on the population's location within the range. However, the modeled population growth rate was only minimally affected by the manipulations in most populations. The inverse responses of many of the demographic rates may allow populations to demographically buffer against the climate manipulations. However, in one low elevation edge population the negative effect of heating on survival overwhelmed the positive effect on germination, indicating that the capacity of populations to demographically buffer may have a limit.

How Much Do Additional Mailings and Telephone Calls Contribute to Response Rates in a Survey of Medicare Beneficiaries?

ERIC Educational Resources Information Center

Burkhart, Q.; Haviland, Amelia M.; Kallaur, Paul N.; Edwards, Carol A.; Brown, Julie A.; Elliott, Marc N.

2015-01-01

Surveys often spend substantial money on multiple mailings and telephone calls to ensure high overall response rates and adequate representation of hard-to-reach demographic subgroups. We examine the extent to which an additional mailing and additional sets of telephone calls are effective in attaining these goals across a variety of subgroups in…

Heart Rate Variability: Effect of Exercise Intensity on Postexercise Response

ERIC Educational Resources Information Center

James, David V. B.; Munson, Steven C.; Maldonado-Martin, Sara; De Ste Croix, Mark B. A.

2012-01-01

The purpose of the present study was to investigate the influence of two exercise intensities (moderate and severe) on heart rate variability (HRV) response in 16 runners 1 hr prior to (-1 hr) and at +1 hr, +24 hr, +48 hr, and +72 hr following each exercise session. Time domain indexes and a high frequency component showed a significant decrease…

Prenotification, Incentives, and Survey Modality: An Experimental Test of Methods to Increase Survey Response Rates of School Principals

ERIC Educational Resources Information Center

Jacob, Robin Tepper; Jacob, Brian

2012-01-01

Teacher and principal surveys are among the most common data collection techniques employed in education research. Yet there is remarkably little research on survey methods in education, or about the most cost-effective way to raise response rates among teachers and principals. In an effort to explore various methods for increasing survey response…

Reactive Molecular Dynamics Simulations to Understand Mechanical Response of Thaumasite under Temperature and Strain Rate Effects.

PubMed

Hajilar, Shahin; Shafei, Behrouz; Cheng, Tao; Jaramillo-Botero, Andres

2017-06-22

Understanding the structural, thermal, and mechanical properties of thaumasite is of great interest to the cement industry, mainly because it is the phase responsible for the aging and deterioration of civil infrastructures made of cementitious materials attacked by external sources of sulfate. Despite the importance, effects of temperature and strain rate on the mechanical response of thaumasite had remained unexplored prior to the current study, in which the mechanical properties of thaumasite are fully characterized using the reactive molecular dynamics (RMD) method. With employing a first-principles based reactive force field, the RMD simulations enable the description of bond dissociation and formation under realistic conditions. From the stress-strain curves of thaumasite generated in the x, y, and z directions, the tensile strength, Young's modulus, and fracture strain are determined for the three orthogonal directions. During the course of each simulation, the chemical bonds undergoing tensile deformations are monitored to reveal the bonds responsible for the mechanical strength of thaumasite. The temperature increase is found to accelerate the bond breaking rate and consequently the degradation of mechanical properties of thaumasite, while the strain rate only leads to a slight enhancement of them for the ranges considered in this study.

Ambulatory blood pressure and heart rate in paramedics: effects of cynical hostility and defensiveness.

PubMed

Jamner, L D; Shapiro, D; Goldstein, I B; Hug, R

1991-01-01

Ambulatory blood pressure and heart rate responses were obtained in 33 male paramedics during a 24-hour work shift to examine the effects of episodes of occupational stress on cardiovascular reactivity and subjective reports of stress. The aim of this study was to determine how individual differences in cynical hostility and defensiveness interacted with situational demands to affect cardiovascular responses in a natural setting. Defensiveness was found to interact significantly with cynical hostility in predicting subjects' heart rate responses in different work contexts. Specifically, in a hospital setting involving interpersonal conflict, subjects who were high in both defensiveness and hostility showed heart rate responses approximately 10 bpm higher than subjects who were high in hostility but low in defensiveness. The same pattern of relationships was obtained for diastolic blood pressure. High and low hostile subjects were also found to differ from each other in their daily mean levels of ambulatory blood pressure during awake and sleep periods. These findings obtained in a natural setting lend further support to the significance of cynical hostility for cardiovascular reactivity. The results for defensiveness suggest the need for further research on the role of conflicting attitudes in the pathophysiology of cardiovascular diseases.

Signal functions in delayed reinforcement

PubMed Central

Lattal, Kennon A.

1984-01-01

Three experiments were conducted with pigeons to examine the role of the signal in delay-of-reinforcement procedures. In the first, a blackout accompanying a period of nonreinforcement increased key-peck response rates maintained by immediate reinforcement. The effects of dissociating the blackout from the delay interval were examined in the second experiment. In three conditions, blackouts and unsignaled delays were negatively correlated or occurred randomly with respect to one another. A signaled delay and an unsignaled delay that omitted the blackouts were studied in two other conditions. All delay-of-reinforcement conditions generally produced response rates lower than those produced by immediate reinforcement. Signaled delays maintained higher response rates than did any of the various unsignaled-delay conditions, with or without dissociated blackouts. The effects of these latter conditions did not differ systematically from one another. The final experiment showed that response rates varied as a function of the frequency with which a blackout accompanied delay intervals. By eliminating a number of methodological difficulties present in previous delay-of-reinforcement experiments, these results suggest the importance of the signal in maintaining responding during delay-of-reinforcement procedures and, conversely, the importance of the delay interval in decreasing responding. PMID:16812387

Do guided internet-based interventions result in clinically relevant changes for patients with depression? An individual participant data meta-analysis.

PubMed

Karyotaki, Eirini; Ebert, David Daniel; Donkin, Liesje; Riper, Heleen; Twisk, Jos; Burger, Simone; Rozental, Alexander; Lange, Alfred; Williams, Alishia D; Zarski, Anna Carlotta; Geraedts, Anna; van Straten, Annemieke; Kleiboer, Annet; Meyer, Björn; Ünlü Ince, Burçin B; Buntrock, Claudia; Lehr, Dirk; Snoek, Frank J; Andrews, Gavin; Andersson, Gerhard; Choi, Isabella; Ruwaard, Jeroen; Klein, Jan Philipp; Newby, Jill M; Schröder, Johanna; Laferton, Johannes A C; Van Bastelaar, Kim; Imamura, Kotaro; Vernmark, Kristofer; Boß, Leif; Sheeber, Lisa B; Kivi, Marie; Berking, Matthias; Titov, Nickolai; Carlbring, Per; Johansson, Robert; Kenter, Robin; Perini, Sarah; Moritz, Steffen; Nobis, Stephanie; Berger, Thomas; Kaldo, Viktor; Forsell, Yvonne; Lindefors, Nils; Kraepelien, Martin; Björkelund, Cecilia; Kawakami, Norito; Cuijpers, Pim

2018-06-19

Little is known about clinically relevant changes in guided Internet-based interventions for depression. Moreover, methodological and power limitations preclude the identification of patients' groups that may benefit more from these interventions. This study aimed to investigate response rates, remission rates, and their moderators in randomized controlled trials (RCTs) comparing the effect of guided Internet-based interventions for adult depression to control groups using an individual patient data meta-analysis approach. Literature searches in PubMed, Embase, PsycINFO and Cochrane Library resulted in 13,384 abstracts from database inception to January 1, 2016. Twenty-four RCTs (4889 participants) comparing a guided Internet-based intervention with a control group contributed data to the analysis. Missing data were multiply imputed. To examine treatment outcome on response and remission, mixed-effects models with participants nested within studies were used. Response and remission rates were calculated using the Reliable Change Index. The intervention group obtained significantly higher response rates (OR = 2.49, 95% CI 2.17-2.85) and remission rates compared to controls (OR = 2.41, 95% CI 2.07-2.79). The moderator analysis indicated that older participants (OR = 1.01) and native-born participants (1.66) were more likely to respond to treatment compared to younger participants and ethnic minorities respectively. Age (OR = 1.01) and ethnicity (1.73) also moderated the effects of treatment on remission.Moreover, adults with more severe depressive symptoms at baseline were more likely to remit after receiving internet-based treatment (OR = 1.19). Guided Internet-based interventions lead to substantial positive treatment effects on treatment response and remission at post-treatment. Thus, such interventions may complement existing services for depression and potentially reduce the gap between the need and provision of evidence-based treatments. Copyright © 2018. Published by Elsevier Ltd.

Addition of cyclophosphamide and higher doses of dexamethasone do not improve outcomes of patients with AL amyloidosis treated with bortezomib.

PubMed

Kastritis, E; Gavriatopoulou, M; Roussou, M; Fotiou, D; Ziogas, D C; Migkou, M; Eleutherakis-Papaiakovou, E; Panagiotidis, I; Kanellias, N; Psimenou, E; Papadopoulou, E; Pamboucas, C; Manios, E; Gakiopoulou, H; Ntalianis, A; Tasidou, A; Giannouli, S; Terpos, E; Dimopoulos, M A

2017-06-16

Bortezomib, in combination with dexamethasone (VD) or with the addition of cyclophosphamide (VCD), is highly effective in patients with amyloid light-chain (AL) amyloidosis. Currently, VCD is considered as a primary regimen for patients with AL, but it is not clear whether the addition of cyclophosphamide to VD further and significantly improves efficacy, given the substantial activity of bortezomib itself. We retrospectively compared the outcomes of 101 patients with AL amyloidosis who received VD (n=59) or VCD (n=42) in two consecutive periods. Early mortality after adjustment for Mayo stage was similar. On intent to treat, a hematologic response rate was 68% for patients treated with VD and 78% for VCD (P=0.26), while complete response+very good partial response (CR+VGPR) rate was 47.5% and 35%, respectively. Higher doses of dexamethasone or twice-weekly bortezomib were not associated with significantly higher CR+VGPR rates. Organ responses occurred in similar rates between the two groups. Median survival was similar (33 vs 36 months, P=0.45) even after adjustment for Mayo stage and dose and schedule of bortezomib and dexamethasone. In conclusion, bortezomib even with low doses of dexamethasone is effective for the treatment of AL amyloidosis; higher doses of dexamethasone and addition of cyclophosphamide do not seem to have a profound effect on efficacy and survival.

Prostaglandins are important in thermoregulation of a reptile (Pogona vitticeps).

PubMed Central

Seebacher, Frank; Franklin, Craig E

2003-01-01

The effectiveness of behavioural thermoregulation in reptiles is amplified by cardiovascular responses, particularly by differential rates of heart beat in response to heating and cooling (heart-rate hysteresis). Heart-rate hysteresis is ecologically important in most lineages of ectothermic reptile, and we demonstrate that heart-rate hysteresis in the lizard Pogona vitticeps is mediated by prostaglandins. In a control treatment (administration of saline), heart rates during heating were significantly faster than during cooling at any given body temperature. When cyclooxygenase 1 and 2 enzymes were inhibited, heart rates during heating were not significantly different from those during cooling. Administration of agonists showed that thromboxane B(2) did not have a significant effect on heart rate, but prostacyclin and prostaglandin F(2alpha) caused a significant increase (3.5 and 13.6 beats min(-1), respectively) in heart rate compared with control treatments. We speculate that heart-rate hysteresis evolved as a thermoregulatory mechanism that may ultimately be controlled by neurally induced stimulation of nitric oxide production, or maybe via photolytically induced production of vitamin D. PMID:12952634

Prostaglandins are important in thermoregulation of a reptile (Pogona vitticeps).

PubMed

Seebacher, Frank; Franklin, Craig E

2003-08-07

The effectiveness of behavioural thermoregulation in reptiles is amplified by cardiovascular responses, particularly by differential rates of heart beat in response to heating and cooling (heart-rate hysteresis). Heart-rate hysteresis is ecologically important in most lineages of ectothermic reptile, and we demonstrate that heart-rate hysteresis in the lizard Pogona vitticeps is mediated by prostaglandins. In a control treatment (administration of saline), heart rates during heating were significantly faster than during cooling at any given body temperature. When cyclooxygenase 1 and 2 enzymes were inhibited, heart rates during heating were not significantly different from those during cooling. Administration of agonists showed that thromboxane B(2) did not have a significant effect on heart rate, but prostacyclin and prostaglandin F(2alpha) caused a significant increase (3.5 and 13.6 beats min(-1), respectively) in heart rate compared with control treatments. We speculate that heart-rate hysteresis evolved as a thermoregulatory mechanism that may ultimately be controlled by neurally induced stimulation of nitric oxide production, or maybe via photolytically induced production of vitamin D.

Slip-deficit rate distribution along the Nankai trough, southwest Japan, with elastic lithosphere and viscoelastic asthenosphere

NASA Astrophysics Data System (ADS)

Noda, A.; Saito, T.; Fukuyama, E.

2017-12-01

In southwest Japan, great thrust earthquakes occurred on the plate interface along the Nankai trough with a recurrence time of about 100 yr. Most studies estimated slip deficits on the seismogenic zone from interseismic GNSS velocity data assuming elastic slip-response functions (e.g. Loveless and Meade, 2016; Yokota et al., 2016). The observed surface velocities, however, include effects of viscoelastic relaxation in the asthenosphere caused by slip history of seismic cycles on the plate interface. Following Noda et al. (2013, GJI), the interseismic surface velocities due to seismic cycle can be represented by the superposition of (1) completely relaxed viscoelastic response to steady slip rate over the whole plate interface, (2) completely relaxed viscoelastic response to steady slip deficit rate in the seismogenic zone, and (3) surface velocity due to viscoelastic stress relaxation after the last interplate earthquake. Subtracting calculated velocities due to steady slip (1) from velocity data observed after the postseismic stress relaxation (3) decays sufficiently, we can formulate an inverse problem of estimating slip deficit rates from the residual velocities using completely relaxed slip-response functions. In an elastic (lithosphere) - viscoelastic (asthenosphere) layered half-space, the completely relaxed responses do not depend on the viscosity of asthenosphere, but depend on the thickness of lithosphere. In this study, we investigate the effects of structure model on the estimation of slip deficit rate distribution. First, we analyze GNSS daily coordinate data (GEONET F3 Solution, GSI), and obtain surface velocity data for overlapped periods of 6 yr (1996-2002, 1999-2005, 2002-2008, 2005-2011). There is no significant temporal change in the velocity data, which suggests that postseismic stress relaxations after the 1944 Tonankai and the 1946 Nankai earthquakes decayed sufficiently. Next, we estimate slip deficit rate distribution from velocity data from 2005 to 2011 together with seafloor geodetic data (Yokota et al., 2016). There is a significant difference between the results using elastic and completely relaxed responses. While the result using elastic responses shows high slip-deficit rate zone in coastal regions, they are located trenchward if using completely relaxed responses.

Incorporating the gas analyzer response time in gas exchange computations.

PubMed

Mitchell, R R

1979-11-01

A simple method for including the gas analyzer response time in the breath-by-breath computation of gas exchange rates is described. The method uses a difference equation form of a model for the gas analyzer in the computation of oxygen uptake and carbon dioxide production and avoids a numerical differentiation required to correct the gas fraction wave forms. The effect of not accounting for analyzer response time is shown to be a 20% underestimation in gas exchange rate. The present method accurately measures gas exchange rate, is relatively insensitive to measurement errors in the analyzer time constant, and does not significantly increase the computation time.

Behavioral regulation of gravity: schedule effects under escape-avoidance procedures1

PubMed Central

Clark, Fogle C.; Lange, Karl O.; Belleville, Richard E.

1973-01-01

Squirrel monkeys were restrained in a centrifuge capsule and trained to escape and avoid increases in artificial gravity. During escape-avoidance, lever responses reduced centrifugally simulated gravity or postponed scheduled increases. The effect of variation in the interval of postponement (equal to the duration of decrease produced by escape responses) was studied under a multiple schedule of four components. Three components were gravity escape-avoidance with postponement times of 20, 40, and 60 sec. The fourth component was extinction. Each component was associated with a different auditory stimulus. Rate of responding decreased with increasing postponement time and higher mean g-levels occurred at shorter intervals of postponement. Effects of the schedule parameter on response rate and mean g-level were similar to effects of the schedule on free-operant avoidance and on titration behavior maintained by shock. ImagesFig. 1. PMID:4202386

The accent method of voice therapy: effect of accentuations on FO, SPL, and airflow.

PubMed

Kotby, M N; Shiromoto, O; Hirano, M

1993-12-01

The effect of the increased flow rate (delta U) in response to the Accent Method exercises on fundamental frequency (FO) and sound pressure level (SPL) was studied in three subjects (professionally trained, trained, and untrained in this method). In all the subjects, the rhythmic accentuated exercises produced a variable degree of increase in FO (delta FO) and SPL (delta SPL). The professionally trained subject showed greater delta FO and delta SPL in response to the delta U in the fastest tempo, which requires higher skills. Both trained subjects showed a greater correlation between delta U and both delta SPL and delta FO, as well as between delta FO and delta SPL, as compared to the untrained subject. The effects of the accentuated exercises on FO and SPL in response to the increased airflow rate (delta U) thus appear to demonstrate the treating effectiveness of the Accent Method.

Responses of growth, photosynthesis and VOC emissions of Pinus tabulaeformis Carr. Exposure to elevated CO2 and/or elevated O3 in an urban area.

PubMed

Xu, Sheng; Chen, Wei; Huang, Yanqing; He, Xingyuan

2012-03-01

Responses of growth, photosynthesis and emission of volatile organic compounds of Pinus tabulaeformis exposed to elevated CO(2) (700 ppm) and O(3) (80 ppb) were studied in open top chambers. Elevated CO(2) increased growth, but it did not significantly (p > 0.05) affect net photosynthetic rate, stomatal conductance, chlorophyll content, the maximum quantum yield of photosystem II, or the effective quantum yield of photosystem II electron transport after 90 d of gas exposure. Elevated O(3) decreased growth (by 42.2% in needle weight and 25.8% in plant height), net photosynthetic rate and stomatal conductance after 90 d of exposure, but its negative effects were alleviated by elevated CO(2). Elevated O(3) significantly (p < 0.05) increased the emission rate of volatile organic compounds, which may be a helpful response to protect photosynthetic apparatus against O(3) damage.

Dose rate mapping of VMAT treatments

NASA Astrophysics Data System (ADS)

Podesta, Mark; Antoniu Popescu, I.; Verhaegen, Frank

2016-06-01

Human tissues exhibit a varying response to radiation dose depending on the dose rate and fractionation scheme used. Dose rate effects have been reported for different radiations, and tissue types. The literature indicates that there is not a significant difference in response for low-LET radiation when using dose rates between 1 Gy min-1 and 12 Gy min-1 but lower dose rates have an observable sparing effect on tissues and a differential effect between tissues. In intensity-modulated radiotherapy such as volumetric modulated arc therapy (VMAT) the dose can be delivered with a wide range of dose rates. In this work we developed a method based on time-resolved Monte Carlo simulations to quantify the dose rate frequency distribution for clinical VMAT treatments for three cancer sites, head and neck, lung, and pelvis within both planning target volumes (PTV) and normal tissues. The results show a wide range of dose rates are used to deliver dose in VMAT and up to 75% of the PTV can have its dose delivered with dose rates  <1 Gy min-1. Pelvic plans on average have a lower mean dose rate within the PTV than lung or head and neck plans but a comparable mean dose rate within the organs at risk. Two VMAT plans that fulfil the same dose objectives and constraints may be delivered with different dose rate distributions, particularly when comparing single arcs to multiple arc plans. It is concluded that for dynamic plans, the dose rate range used varies to a larger degree than previously assumed. The effect of the dose rate range in VMAT on clinical outcome is unknown.

Inflated responsibility in obsessive compulsive disorder: validation of an operational definition.

PubMed

Rhéaume, J; Ladouceur, R; Freeston, M H; Letarte, H

1995-02-01

An excessive sense of responsibility has been identified in obsessive-compulsive disorder (OCD) where patients evaluate their thoughts in terms of the harm they could cause to themselves or others. In a new definition, responsibility was defined as the belief that one possesses pivotal power to provoke or prevent subjective crucial negative outcomes. In order to empirically test the validity of this definition, two studies used a semi-idiographic design to evaluate responsibility across ambiguous situations related to major OCD themes like contamination, verification, somatic concerns, loss of control, making errors, sexuality and magical thinking. In the first study, 397 volunteer adults participated in the experiment. For each situation, subjects briefly described a possible negative outcome and then rated this outcome on four dimensions: (1) probability; (2) severity; (3) influence; and (4) pivotal influence, using a 9-point Likert scale. Finally Ss rated perceived responsibility and personal relevance. Highly relevant situations were retained for the final analysis. Regression analysis suggested that influence and pivotal influence were better predictors of responsibility ratings than probability and severity. The second study examined the effect of the order of the questions on the responsibility ratings. A first group of Ss (n = 85) answered the Responsibility Questionnaire (RQ) in the original order, while a second group (n = 53) rated responsibility before the other ratings. Regression analysis showed that although proportion of variance explained diminished when the order was reversed, pivotal influence was still the best predictor of responsibility. Results are discussed in terms of current models of OCD and implications for future research and cognitive treatment are identified.

Effects of Beta-blockers on Punished Responding and on Heart Rate in Pigeons

DTIC Science & Technology

1986-06-17

in pigeons. The present study attempted to confirm that fmding, to compare the effects of propranolol, metoprolol , and atenolol with that of...occurred at approximately 15% iii of the high unpunished response rates. Propranolol, atenolol, and metoprolol doses from 1.0 to 10.0 mg!kg, i.m. and...and, to a somewhat lesser extent, metoprolol produced large dose-related decreases. Atenolol’s effect was small. Chlordiazepoxide increased heart rate

Individual differences in emotion processing: how similar are diffusion model parameters across tasks?

PubMed

Mueller, Christina J; White, Corey N; Kuchinke, Lars

2017-11-27

The goal of this study was to replicate findings of diffusion model parameters capturing emotion effects in a lexical decision task and investigating whether these findings extend to other tasks of implicit emotion processing. Additionally, we were interested in the stability of diffusion model parameters across emotional stimuli and tasks for individual subjects. Responses to words in a lexical decision task were compared with responses to faces in a gender categorization task for stimuli of the emotion categories: happy, neutral and fear. Main effects of emotion as well as stability of emerging response style patterns as evident in diffusion model parameters across these tasks were analyzed. Based on earlier findings, drift rates were assumed to be more similar in response to stimuli of the same emotion category compared to stimuli of a different emotion category. Results showed that emotion effects of the tasks differed with a processing advantage for happy followed by neutral and fear-related words in the lexical decision task and a processing advantage for neutral followed by happy and fearful faces in the gender categorization task. Both emotion effects were captured in estimated drift rate parameters-and in case of the lexical decision task also in the non-decision time parameters. A principal component analysis showed that contrary to our hypothesis drift rates were more similar within a specific task context than within a specific emotion category. Individual response patterns of subjects across tasks were evident in significant correlations regarding diffusion model parameters including response styles, non-decision times and information accumulation.

Frequency-dependence of the slow force response.

PubMed

von Lewinski, Dirk; Zhu, Danan; Khafaga, Mounir; Kockskamper, Jens; Maier, Lars S; Hasenfuss, Gerd; Pieske, Burkert

2008-05-01

Stretch induces biphasic inotropic effects in mammalian myocardium. A delayed component (slow force response, SFR) has been demonstrated in various species, however, experimental conditions varied and the underlying mechanisms are controversial. The physiological relevance of the SFR is poorly understood. Experiments were performed in ventricular muscle strips from failing human hearts and non-failing rabbit hearts. Upon stretch, twitch force was assessed at basal conditions (1 Hz, 37 degrees C) and after changing stimulation frequency with and without blockade of the Na+/H+-exchanger-1 (NHE1) or reverse-mode Na+/Ca2+-exchange (NCX). Action potential duration (APD) was assessed using floating electrodes. Low stimulation rates (0.2 Hz) potentiated and higher stimulation rates (2 and 3 Hz) reduced the SFR. The extent of SFR inhibition by NHE1 or NCX inhibition was not affected by stimulation rate. APD decreased at 0.2 Hz but was not altered at higher stimulation rates. The data demonstrate frequency-dependence of the SFR with greater positive inotropic effects at lower stimulation rates. Subcellular mechanisms underlying the SFR are not fundamentally affected by stimulation rate. The SFR may have more pronounced physiological effects at lower heart rates.

The behavioral response of Lasioderma serricorne (Coleoptera: Anobiidae) to citronellal, citral, and rutin.

PubMed

Lü, Jianhua; Liu, Shuli

2016-01-01

The behavioral response of Lasioderma serricorne adults to citronellal, citral, and rutin was investigated by using the area preference method. The L. serricorne adults were exposed to citronellal, and citral at the rate of 1:10, 1:50, 1:100 and 1:1000 (citronellal: ethanol, v/v) for 1, 2, 12 and 24 h, to rutin at the rate of 10, 30 and 90 g/m(2) for 1, 2, 12 and 24 h, respectively. The citronellal and citral had attractive activity at the low rates and repellent potential at the high rates. The highest behavioral response values of L. serricorne adults to citronellal and citral were -88.89 % at the rate of 1:100 and 100.00 % at the rate of 1:50 respectively. Rutin had strong repellent effectiveness on L. serricorne adults, which significantly increased with increasing rates with the highest behavioral response values 100.00 % at the rate of 90 g/m(2) after 12 h exposure. These data suggest that the citronellal, citral, and rutin have great potential for preventing stored products from L. serricorne infestation.

A quantitative analysis of the effects of qualitatively different reinforcers on fixed ratio responding in inbred strains of mice

PubMed Central

Hutsell, Blake A.; Newland, M. Christopher

2013-01-01

Previous studies of inbred mouse strains have shown reinforcer-strain interactions that may potentially mask differences among strains in memory performance. The present research examined the effects of two qualitatively different reinforcers (heterogeneous mix of flavored pellets and sweetened-condensed milk) on responding maintained by fixed-ratio schedules of reinforcement in three inbred strains of mice (BALB/c, C57BL/6, & DBA/2). Responses rates for all strains were a bitonic (inverted U) function of the size of the fixed-ratio schedule and were generally higher when responding was maintained by milk. For the DBA/2 and C57BL/6 and to a lesser extent the BALB/c, milk primarily increased response rates at moderate fixed ratios, but not at the largest fixed ratios tested. A formal model of ratio-schedule performance, Mathematical Principles of Reinforcement (MPR), was applied to the response rate functions of individual mice. According to MPR, the differences in response rates maintained by pellets and milk were mostly due to changes in motoric processes as indicated by changes in the minimum response time (δ) produced by each reinforcer type and not specific activation (a), a model term that represents value and is correlated with reinforcer magnitude and the break point obtained under progressive ratio schedules. In addition, MPR also revealed that, although affected by reinforcer type, a parameter interpreted as the rate of saturation of working memory (λ), differed among the strains. PMID:23357283

The use of incentives in vulnerable populations for a telephone survey: a randomized controlled trial.

PubMed

Knoll, Megan; Soller, Lianne; Ben-Shoshan, Moshe; Harrington, Daniel; Fragapane, Joey; Joseph, Lawrence; La Vieille, Sebastien; St-Pierre, Yvan; Wilson, Kathi; Elliott, Susan; Clarke, Ann

2012-10-19

Poor response rates in prevalence surveys can lead to nonresponse bias thereby compromising the validity of prevalence estimates. We conducted a telephone survey of randomly selected households to estimate the prevalence of food allergy in the 10 Canadian provinces between May 2008 and March 2009 (the SCAAALAR study: Surveying Canadians to Assess the Prevalence of Common Food Allergies and Attitudes towards Food LAbeling and Risk). A household response rate of only 34.6% was attained, and those of lower socioeconomic status, lower education and new Canadians were underrepresented. We are now attempting to target these vulnerable populations in the SPAACE study (Surveying the Prevalence of Food Allergy in All Canadian Environments) and are evaluating strategies to increase the response rate. Although the success of incentives to increase response rates has been demonstrated previously, no studies have specifically examined the use of unconditional incentives in these vulnerable populations in a telephone survey. The pilot study will compare response rates between vulnerable Canadian populations receiving and not receiving an incentive. Randomly selected households were randomly assigned to receive either a $5 incentive or no incentive. The between group differences in response rates and 95% confidence intervals (CIs) were calculated. The response rates for the incentive and non-incentive groups were 36.1% and 28.7% respectively, yielding a between group difference of 7.4% (-0.7%, 15.6%). Although the wide CI precludes definitive conclusions, our results suggest that unconditional incentives are effective in vulnerable populations for telephone surveys.

EFFECTS OF BACTERIAL ENDOTOXIN ON WATER INTAKE, FOOD INTAKE, AND BODY TEMPERATURE IN THE ALBINO RAT

PubMed Central

Holmes, John E.; Miller, Neal E.

1963-01-01

Intraperitoneal injections of Escherichia coli endotoxin in albino rats produces a decrease in food and water intake and a drop in body temperature. The drop in temperature and in water intake is probably proportional to the size of the dose. Using a behavioral test in which animals are trained to press a bar at a steady rate for intermittent food or water reward, it is possible to demonstrate the sudden onset of the toxin effect at 30 to 45 minutes after injection. In any group of rats, all of whom were presumably exposed to E. coli, three types of response to toxin can be found: (a) Sharp reduction in water intake 30 minutes after injection. (b) Little or no change in intake or rate of working for water reward. (c) Immediate depression of work rate. These three types of reaction appear related to previous experience with the toxin. The "normal" or "inexperienced" reaction a was seen in animals who had not been given toxin before. The "protected" reaction b, with little or no effect of toxin injection on response rate was frequently found 4 to 5 days after a previous injection. The "susceptible" reaction c was found in three animals after 14 or more days had passed since a previous injection. Injections of toxin into the lateral hypothalamic region of four animals through implanted cannulae had no effect on the rate of bar pressing for water. Control injections of lidocaine blocked response rate completely for brief periods in three animals. PMID:14067912

Combinations of response-reinforcer relations in periodic and aperiodic schedules.

PubMed

Kuroda, Toshikazu; Cançado, Carlos R X; Lattal, Kennon A; Elcoro, Mirari; Dickson, Chata A; Cook, James E

2013-03-01

Key pecking of 4 pigeons was studied under a two-component multiple schedule in which food deliveries were arranged according to a fixed and a variable interfood interval. The percentage of response-dependent food in each component was varied, first in ascending (0, 10, 30, 70 and 100%) and then in descending orders, in successive conditions. The change in response rates was positively related to the percentage of response-dependent food in each schedule component. Across conditions, positively accelerated and linear patterns of responding occurred consistently in the fixed and variable components, respectively. These results suggest that the response-food dependency determines response rates in periodic and aperiodic schedules, and that the temporal distribution of food determines response patterns independently of the response-food dependency. Running rates, but not postfood pauses, also were positively related to the percentage of dependent food in each condition, in both fixed and variable components. Thus, the relation between overall response rate and the percentage of dependent food was mediated by responding that occurred after postfood pausing. The findings together extend previous studies wherein the dependency was either always present or absent, and increase the generality of the effects of variations in the response-food dependency from aperiodic to periodic schedules. © Society for the Experimental Analysis of Behavior.

Immune interference in the setting of same-day administration of two similar inactivated alphavirus vaccines: eastern equine and western equine encephalitis.

PubMed

Reisler, Ronald B; Gibbs, Paul H; Danner, Denise K; Boudreau, Ellen F

2012-11-26

We compared the effect on primary vaccination plaque-reduction neutralization 80% titers (PRNT80) responses of same-day administration (at different injection sites) of two similar investigational inactivated alphavirus vaccines, eastern equine encephalitis (EEE) vaccine (TSI-GSD 104) and western equine encephalitis (WEE) vaccine (TSI-GSD 210) to separate administration. Overall, primary response rate for EEE vaccine was 524/796 (66%) and overall primary response rate for WEE vaccine was 291/695 (42%). EEE vaccine same-day administration yielded a 59% response rate and a responder geometric mean titer (GMT)=89 while separate administration yielded a response rate of 69% and a responder GMT=119. WEE vaccine same-day administration yielded a 30% response rate and a responder GMT=53 while separate administration yielded a response rate of 54% and a responder GMT=79. EEE response rates for same-day administration (group A) vs. non-same-day administration (group B) were significantly affected by gender. A logistic regression model predicting response to EEE comparing group B to group A for females yielded an OR=4.10 (95% CL 1.97-8.55; p=.0002) and for males yielded an OR=1.25 (95% CL 0.76-2.07; p=.3768). WEE response rates for same-day administration vs. non-same-day administration were independent of gender. A logistic regression model predicting response to WEE comparing group B to group A yielded an OR=2.14 (95% CL 1.22-3.73; p=.0077). We report immune interference occurring with same-day administration of two completely separate formalin inactivated viral vaccines in humans. These findings combined with the findings of others regarding immune interference would argue for a renewed emphasis on studying the immunological mechanisms of induction of inactivated viral vaccine protection. Copyright © 2012. Published by Elsevier Ltd.

Supplemental choline does not attenuate the effects of neonatal ethanol administration on habituation of the heart rate orienting response in rats.

PubMed

Hunt, Pamela S; Jacobson, Sarah E; Kim, Sarah

2014-01-01

Several studies using rodent subjects have now shown that extra dietary choline may prevent or even reverse the deleterious effects of pre- and early post-natal ethanol administration. Choline supplementation has been shown to attenuate many, although not all, of ethanol's effects on brain development and behavior. Our laboratory has consistently reported impaired habituation of the heart rate orienting response to a novel olfactory stimulus in animals exposed to ethanol on postnatal days (PD) 4-9. Here we examine whether supplemental choline given both during and after ethanol administration could alleviate these ethanol-induced deficits. Subjects were given 5g/kg/day ethanol or sham intubations on PD 4-9. Half of the subjects in each group were given a single daily s.c. injection of choline chloride on PD 4-20, while the other half were injected daily with saline. Pups were tested for heart rate orienting and response habituation in a single test session on PD 23. Results replicated the ethanol-induced impairment in response habituation. However, choline supplementation had no effect on orienting or habituation in either neonatal treatment group. These findings indicate that habituation deficits induced by ethanol are not alleviated by extra dietary choline using these parameters. Choline holds great promise as a treatment for some fetal alcohol effects, but is not an effective treatment for all ethanol-related deficits. Copyright © 2014 Elsevier Inc. All rights reserved.

Supplemental choline does not attenuate the effects of neonatal ethanol administration on habituation of the heart rate orienting response in rats

PubMed Central

Hunt, Pamela S.; Jacobson, Sarah E.; Kim, Sarah

2014-01-01

Several studies using rodent subjects have now shown that extra dietary choline may prevent or even reverse the deleterious effects of pre- and early post-natal ethanol administration. Choline supplementation has been shown to attenuate many, although not all, of ethanol’s effects on brain development and behavior. Our laboratory has consistently reported impaired habituation of the heart rate orienting response to a novel olfactory stimulus in animals exposed to ethanol on postnatal days (PD) 4–9. Here we examine whether supplemental choline given both during and after ethanol administration could alleviate these ethanol-induced deficits. Subjects were given 5 g/kg/day ethanol or sham intubations on PD 4–9. Half of the subjects in each group were given a single daily s.c. injection of choline chloride on PD 4–20, while the other half were injected daily with saline. Pups were tested for heart rate orienting and response habituation in a single test session on PD 23. Results replicated the ethanol-induced impairment in response habituation. However, choline supplementation had no effect on orienting or habituation in either neonatal treatment group. These findings indicate that habituation deficits induced by ethanol are not alleviated by extra dietary choline using these parameters. Choline holds great promise as a treatment for some fetal alcohol effects, but is not an effective treatment for all ethanol-related deficits. PMID:24907459

The general matching law describes choice on concurrent variable-interval schedules of wheel-running reinforcement.

PubMed

Belke, T W; Belliveau, J

2001-05-01

Six male Wistar rats were exposed to concurrent variable-interval schedules of wheel-running reinforcement. The reinforcer associated with each alternative was the opportunity to run for 15 s, and the duration of the changeover delay was 1 s. Results suggested that time allocation was more sensitive to relative reinforcement rate than was response allocation. For time allocation, the mean slopes and intercepts were 0.82 and 0.008, respectively. In contrast, for response allocation, mean slopes and intercepts were 0.60 and 0.03, respectively. Correction for low response rates and high rates of changing over, however, increased slopes for response allocation to about equal those for time allocation. The results of the present study suggest that the two-operant form of the matching law can be extended to wheel-running reinforcement. 'I'he effects of a low overall response rate, a short Changeover delay, and long postreinforcement pausing on the assessment of matching in the present study are discussed.

Dose-response characteristics of an amorphous silicon EPID.

PubMed

Winkler, Peter; Hefner, Alfred; Georg, Dietmar

2005-10-01

Electronic portal imaging devices (EPIDs) were originally developed for the purpose of patient setup verification. Nowadays, they are increasingly used as dosimeters (e.g., for IMRT verification and linac-specific QA). A prerequisite for any clinical dosimetric application is a detailed understanding of the detector's dose-response behavior. The aim of this study is to investigate the dosimetric properties of an amorphous silicon EPID (Elekta IVIEWGT) with respect to three photon beam qualities: 6, 10, and 25 MV. The EPID showed an excellent temporal stability on short term as well as on long term scales. The stability throughout the day was strongly influenced by warming up, which took several hours and affected EPID response by 2.5%. Ghosting effects increased the sensitivity of the EPID. They became more pronounced with decreasing time intervals between two exposures as well as with increasing dose. Due to ghosting, changes in pixel sensitivity amounted up to 16% (locally) for the 25 MV photon beam. It was observed that the response characteristics of our EPID depended on dose as well as on dose rate. Doubling the dose rate increased the EPID sensitivity by 1.5%. This behavior was successfully attributed to a dose per frame effect, i.e., a nonlinear relationship between the EPID signal and the dose which was delivered to the panel between two successive readouts. The sensitivity was found to vary up to 10% in the range of 1 to 1000 monitor units. This variation was governed by two independent effects. For low doses, the EPID signal was reduced due to the linac's changing dose rate during startup. Furthermore, the detector reading was influenced by intrabeam variations of EPID sensitivity, namely, an increase of detector response during uniform exposure. For the beam qualities which were used, the response characteristics of the EPID did not depend on energy. Differences in relative dose-response curves resulted from energy dependent temporal output characteristics of the accelerator. If ghosting is prevented from affecting the results and all dose-response effects are properly corrected for, the EPID signal becomes independent of dose rate, dose, and exposure time.

How many mailouts? Could attempts to increase the response rate in the Iraq war cohort study be counterproductive?

PubMed Central

Tate, A Rosemary; Jones, Margaret; Hull, Lisa; Fear, Nicola T; Rona, Roberto; Wessely, Simon; Hotopf, Matthew

2007-01-01

Background Low response and reporting errors are major concerns for survey epidemiologists. However, while nonresponse is commonly investigated, the effects of misclassification are often ignored, possibly because they are hard to quantify. We investigate both sources of bias in a recent study of the effects of deployment to the 2003 Iraq war on the health of UK military personnel, and attempt to determine whether improving response rates by multiple mailouts was associated with increased misclassification error and hence increased bias in the results. Methods Data for 17,162 UK military personnel were used to determine factors related to response and inverse probability weights were used to assess nonresponse bias. The percentages of inconsistent and missing answers to health questions from the 10,234 responders were used as measures of misclassification in a simulation of the 'true' relative risks that would have been observed if misclassification had not been present. Simulated and observed relative risks of multiple physical symptoms and post-traumatic stress disorder (PTSD) were compared across response waves (number of contact attempts). Results Age, rank, gender, ethnic group, enlistment type (regular/reservist) and contact address (military or civilian), but not fitness, were significantly related to response. Weighting for nonresponse had little effect on the relative risks. Of the respondents, 88% had responded by wave 2. Missing answers (total 3%) increased significantly (p < 0.001) between waves 1 and 4 from 2.4% to 7.3%, and the percentage with discrepant answers (total 14%) increased from 12.8% to 16.3% (p = 0.007). However, the adjusted relative risks decreased only slightly from 1.24 to 1.22 for multiple physical symptoms and from 1.12 to 1.09 for PTSD, and showed a similar pattern to those simulated. Conclusion Bias due to nonresponse appears to be small in this study, and increasing the response rates had little effect on the results. Although misclassification is difficult to assess, the results suggest that bias due to reporting errors could be greater than bias caused by nonresponse. Resources might be better spent on improving and validating the data, rather than on increasing the response rate. PMID:18045472

Physiological responses and scope for growth upon medium-term exposure to the combined effects of ocean acidification and temperature in a subtidal scavenger Nassarius conoidalis.

PubMed

Zhang, Haoyu; Shin, Paul K S; Cheung, S G

2015-05-01

Physiological responses (ingestion rate, absorption rate and efficiency, respiration, rate, excretion rate) and scope for growth of a subtidal scavenging gastropod Nassarius conoidalis under the combined effects of ocean acidification (pCO2 levels: 380, 950, 1250 μatm) and temperature (15, 30 °C) were investigated for 31 days. There was a significant reduction in all the physiological rates and scope for growth following short-term exposure (1-3 days) to elevated pCO2 except absorption efficiency at 15 °C and 30 °C, and respiration rate and excretion rate at 15 °C. The percentage change in the physiological rates ranged from 0% to 90% at 15 °C and from 0% to 73% at 30 °C when pCO2 was increased from 380 μatm to 1250 μatm. The effect of pCO2 on the physiological rates was enhanced at high temperature for ingestion, absorption, respiration and excretion. When the exposure period was extended to 31 days, the effect of pCO2 was significant on the ingestion rate only. All the physiological rates remained unchanged when temperature increased from 24 °C to 30 °C but the rates at 15 °C were significantly lower, irrespective of the duration of exposure. Our data suggested that a medium-term exposure to ocean acidification has no effect on the energetics of N. conoidalis. Nevertheless, the situation may be complicated by a longer term of exposure and/or a reduction in salinity in a warming world. Copyright © 2015 Elsevier Ltd. All rights reserved.

Face-Likeness and Image Variability Drive Responses in Human Face-Selective Ventral Regions

PubMed Central

Davidenko, Nicolas; Remus, David A.; Grill-Spector, Kalanit

2012-01-01

The human ventral visual stream contains regions that respond selectively to faces over objects. However, it is unknown whether responses in these regions correlate with how face-like stimuli appear. Here, we use parameterized face silhouettes to manipulate the perceived face-likeness of stimuli and measure responses in face- and object-selective ventral regions with high-resolution fMRI. We first use “concentric hyper-sphere” (CH) sampling to define face silhouettes at different distances from the prototype face. Observers rate the stimuli as progressively more face-like the closer they are to the prototype face. Paradoxically, responses in both face- and object-selective regions decrease as face-likeness ratings increase. Because CH sampling produces blocks of stimuli whose variability is negatively correlated with face-likeness, this effect may be driven by more adaptation during high face-likeness (low-variability) blocks than during low face-likeness (high-variability) blocks. We tested this hypothesis by measuring responses to matched-variability (MV) blocks of stimuli with similar face-likeness ratings as with CH sampling. Critically, under MV sampling, we find a face-specific effect: responses in face-selective regions gradually increase with perceived face-likeness, but responses in object-selective regions are unchanged. Our studies provide novel evidence that face-selective responses correlate with the perceived face-likeness of stimuli, but this effect is revealed only when image variability is controlled across conditions. Finally, our data show that variability is a powerful factor that drives responses across the ventral stream. This indicates that controlling variability across conditions should be a critical tool in future neuroimaging studies of face and object representation. PMID:21823208

Mediators of compassionate goal intervention effects on human neuroendocrine responses to the Trier Social Stress Test.

PubMed

Erickson, Thane M; Mayer, Stefanie E; Lopez-Duran, Nestor L; Scarsella, Gina M; McGuire, Adam P; Crocker, Jennifer; Abelson, James L

2017-11-01

The hypothalamic-pituitary-adrenal (HPA) axis is thought to mediate the effects of stress on illness. Research has identified a limited number of psychological variables that modulate human HPA responses to stressors (e.g. perceived control and social support). Prosocial goals can reduce subjective stress, but have not been carefully examined in experimental settings where pathways of impact on biological stress markers may be traced. Recent work demonstrated that coaching individuals to strive to help others reduced HPA responses to the Trier Social Stress Test (TSST) relative to other cognitive interventions. However, identification of mediational pathways, which were not examined in the original study, is necessary to determine whether the HPA buffering effects were due to helping motivations (compassionate goals; CGs) rather than via previously identified variables such as control or support. In this new analysis, we combined the original cortisol data with novel observer ratings of interpersonal behavior and psychological variables during the stress task, and conducted new, theory-driven analyses to determine psychological mediators for the intervention's effect on cortisol responses (N = 54; 21 females, 33 males; 486 cortisol samples). Control, support, and task ego-threat failed to account for the effects of the intervention. As hypothesized, self and observer-rated CGs, as well as observer-rated perceptions of participants' interpersonal behavior as morally desirable (but not as dominant or affiliative) were significant mediators of neuroendocrine responses. The findings suggest that stress-reduction interventions based on prosocial behavior should target particular motivational and interpersonal features.

The threshold vs LNT showdown: Dose rate findings exposed flaws in the LNT model part 1. The Russell-Muller debate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Calabrese, Edward J., E-mail: edwardc@schoolph.uma

This paper assesses the discovery of the dose-rate effect in radiation genetics and how it challenged fundamental tenets of the linear non-threshold (LNT) dose response model, including the assumptions that all mutational damage is cumulative and irreversible and that the dose-response is linear at low doses. Newly uncovered historical information also describes how a key 1964 report by the International Commission for Radiological Protection (ICRP) addressed the effects of dose rate in the assessment of genetic risk. This unique story involves assessments by two leading radiation geneticists, Hermann J. Muller and William L. Russell, who independently argued that the report'smore » Genetic Summary Section on dose rate was incorrect while simultaneously offering vastly different views as to what the report's summary should have contained. This paper reveals occurrences of scientific disagreements, how conflicts were resolved, which view(s) prevailed and why. During this process the Nobel Laureate, Muller, provided incorrect information to the ICRP in what appears to have been an attempt to manipulate the decision-making process and to prevent the dose-rate concept from being adopted into risk assessment practices. - Highlights: • The discovery of radiation dose rate challenged the scientific basis of LNT. • Radiation dose rate occurred in males and females. • The dose rate concept supported a threshold dose-response for radiation.« less

Responsibility and the sense of agency enhance empathy for pain

PubMed Central

Lepron, Evelyne; Causse, Michaël; Farrer, Chlöé

2015-01-01

Being held responsible for our actions strongly determines our moral judgements and decisions. This study examined whether responsibility also influences our affective reaction to others' emotions. We conducted two experiments in order to assess the effect of responsibility and of a sense of agency (the conscious feeling of controlling an action) on the empathic response to pain. In both experiments, participants were presented with video clips showing an actor's facial expression of pain of varying intensity. The empathic response was assessed with behavioural (pain intensity estimation from facial expressions and unpleasantness for the observer ratings) and electrophysiological measures (facial electromyography). Experiment 1 showed enhanced empathic response (increased unpleasantness for the observer and facial electromyography responses) as participants' degree of responsibility for the actor's pain increased. This effect was mainly accounted for by the decisional component of responsibility (compared with the execution component). In addition, experiment 2 found that participants' unpleasantness rating also increased when they had a sense of agency over the pain, while controlling for decision and execution processes. The findings suggest that increased empathy induced by responsibility and a sense of agency may play a role in regulating our moral conduct. PMID:25473014

Global patterns in lake ecosystem responses to warming based on the temperature dependence of metabolism.

PubMed

Kraemer, Benjamin M; Chandra, Sudeep; Dell, Anthony I; Dix, Margaret; Kuusisto, Esko; Livingstone, David M; Schladow, S Geoffrey; Silow, Eugene; Sitoki, Lewis M; Tamatamah, Rashid; McIntyre, Peter B

2017-05-01

Climate warming is expected to have large effects on ecosystems in part due to the temperature dependence of metabolism. The responses of metabolic rates to climate warming may be greatest in the tropics and at low elevations because mean temperatures are warmer there and metabolic rates respond exponentially to temperature (with exponents >1). However, if warming rates are sufficiently fast in higher latitude/elevation lakes, metabolic rate responses to warming may still be greater there even though metabolic rates respond exponentially to temperature. Thus, a wide range of global patterns in the magnitude of metabolic rate responses to warming could emerge depending on global patterns of temperature and warming rates. Here we use the Boltzmann-Arrhenius equation, published estimates of activation energy, and time series of temperature from 271 lakes to estimate long-term (1970-2010) changes in 64 metabolic processes in lakes. The estimated responses of metabolic processes to warming were usually greatest in tropical/low-elevation lakes even though surface temperatures in higher latitude/elevation lakes are warming faster. However, when the thermal sensitivity of a metabolic process is especially weak, higher latitude/elevation lakes had larger responses to warming in parallel with warming rates. Our results show that the sensitivity of a given response to temperature (as described by its activation energy) provides a simple heuristic for predicting whether tropical/low-elevation lakes will have larger or smaller metabolic responses to warming than higher latitude/elevation lakes. Overall, we conclude that the direct metabolic consequences of lake warming are likely to be felt most strongly at low latitudes and low elevations where metabolism-linked ecosystem services may be most affected. © 2016 John Wiley & Sons Ltd.

Human comfort response to random motions with a dominant transverse motion

NASA Technical Reports Server (NTRS)

Stone, R. W., Jr.

1975-01-01

Subjective ride comfort response ratings were measured on the Langley Visual Motion Simulator with transverse acceleration inputs with various power spectra shapes and magnitudes. The results show only little influence of spectra shape on comfort response. The effects of magnitude on comfort response indicate the applicability of psychophysical precepts for comfort modeling.

Human comfort response to random motions with a dominant longitudinal motion

NASA Technical Reports Server (NTRS)

Stone, R. W., Jr.

1975-01-01

Subjective ride comfort response ratings were measured on the Langley Visual Motion Simulator with longitudinal acceleration inputs with various power spectra shapes and magnitudes. The results show only little influence of spectra shape on comfort response. The effects of magnitude on comfort response indicate the applicability of psychophysical precepts for comfort modeling.

Human confort response to random motions with a dominant rolling motion

NASA Technical Reports Server (NTRS)

Stone, R. W., Jr.

1975-01-01

Subjective ride comfort response ratings were measured on a visual motion simulator with rolling velocity inputs with various power spectra shapes and magnitudes. The results show only little influence of spectra shape on comfort response. The effects of magnitude on comfort response indicate the applicability of psychophysical precepts for comfort modeling.

The effect of telephone support to evacuees with risks of hypertension and diabetes mellitus after a disaster: the Fukushima Health Management Survey.

PubMed

Horikoshi, Naoko; Ohira, Tetsuya; Yasumura, Seiji; Yabe, Hirooki; Maeda, Masaharu

2017-01-01

Objectives　Fukushima Medical University has been conducting the Fukushima Health Management Survey "Mental Health and Lifestyle Survey" annually as part of the health care of evacuees following the Fukushima Daiichi nuclear power plant accident.　This study aimed to clarify the effects of telephone support performed by nurses or public health nurses. In particular, we investigated the response rates for questionnaire of the following year and the recommended effect of medical support for evacuees with risks of hypertension and diabetes mellitus in the fiscal year 2011 (FY2011).Methods　The study population included evacuees (1,620 people) with risks of hypertension and diabetes mellitus in FY2011. We compared the participants' responses to the FY2012 survey and medical results based on those who received telephone support and those who did not.Results　Evacuees who have received telephone support (telephone supporters) comprised 1,078 people. Evacuees who did not receive telephone support (non-telephone supporters) comprised 542 people.　Telephone supporters consisted of more people from outside Fukushima prefecture (P=0.001), with above high school education (P<0.001), and who were unemployed (P<0.001) compared to non-telephone supporters.　For the FY2012 survey, 616 telephone supporters responded (57.1%), while 248 non-telephone supporters responded (45.8%). The response rate of telephone supporters was significantly higher compared to non-telephone supporters for the FY2012 questionnaire (P<0.001).　In addition, 184 (29.9%) telephone supporters and 68 (27.4%) non-telephone supporters underwent the medical examination.　In the multivariate analysis, responses to the FY2012 questionnaire were significantly associated with receiving telephone support (P=0.016).Conclusion　Telephone supporters had higher response rates for the questionnaire the following year compared to non-telephone supporters. Therefore, telephone support was effective in increasing the questionnaire response rate during the following year.

Substance P Differentially Modulates Firing Rate of Solitary Complex (SC) Neurons from Control and Chronic Hypoxia-Adapted Adult Rats

PubMed Central

Nichols, Nicole L.; Powell, Frank L.; Dean, Jay B.; Putnam, Robert W.

2014-01-01

NK1 receptors, which bind substance P, are present in the majority of brainstem regions that contain CO2/H+-sensitive neurons that play a role in central chemosensitivity. However, the effect of substance P on the chemosensitive response of neurons from these regions has not been studied. Hypoxia increases substance P release from peripheral afferents that terminate in the caudal nucleus tractus solitarius (NTS). Here we studied the effect of substance P on the chemosensitive responses of solitary complex (SC: NTS and dorsal motor nucleus) neurons from control and chronic hypoxia-adapted (CHx) adult rats. We simultaneously measured intracellular pH and electrical responses to hypercapnic acidosis in SC neurons from control and CHx adult rats using the blind whole cell patch clamp technique and fluorescence imaging microscopy. Substance P significantly increased the basal firing rate in SC neurons from control and CHx rats, although the increase was smaller in CHx rats. However, substance P did not affect the chemosensitive response of SC neurons from either group of rats. In conclusion, we found that substance P plays a role in modulating the basal firing rate of SC neurons but the magnitude of the effect is smaller for SC neurons from CHx adult rats, implying that NK1 receptors may be down regulated in CHx adult rats. Substance P does not appear to play a role in modulating the firing rate response to hypercapnic acidosis of SC neurons from either control or CHx adult rats. PMID:24516602

Portal Vein Embolization Before Liver Resection: A Systematic Review

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lienden, K. P. van, E-mail: k.p.vanlienden@amc.uva.nl; Esschert, J. W. van den; Graaf, W. de

2013-02-15

This is a review of literature on the indications, technique, and outcome of portal vein embolization (PVE). A systematic literature search on outcome of PVE from 1990 to 2011 was performed in Medline, Cochrane, and Embase databases. Forty-four articles were selected, including 1,791 patients with a mean age of 61 {+-} 4.1 years. Overall technical success rate was 99.3 %. The mean hypertrophy rate of the FRL after PVE was 37.9 {+-} 0.1 %. In 70 patients (3.9 %), surgery was not performed because of failure of PVE (clinical success rate 96.1 %). In 51 patients (2.8 %), the hypertrophymore » response was insufficient to perform liver resection. In the other 17 cases, 12 did not technically succeed (0.7 %) and 7 caused a complication leading to unresectability (0.4 %). In 6.1 %, resection was cancelled because of local tumor progression after PVE. Major complications were seen in 2.5 %, and the mortality rate was 0.1 %. A head-to-head comparison shows a negative effect of liver cirrhosis on hypertrophy response. The use of n-butyl cyanoacrylate seems to have a greater effect on hypertrophy, but the difference with other embolization materials did not reach statistical significance. No difference in regeneration is seen in patients with cholestasis or chemotherapy. Preoperative PVE has a high technical and clinical success rate. Liver cirrhosis has a negative effect on regeneration, but cholestasis and chemotherapy do not seem to have an influence on the hypertrophy response. The use of n-butyl cyanoacrylate may result in a greater hypertrophy response compared with other embolization materials used.« less

Investigating strength and frequency effects in recognition memory using type-2 signal detection theory.

PubMed

Higham, Philip A; Perfect, Timothy J; Bruno, Davide

2009-01-01

Criterion- versus distribution-shift accounts of frequency and strength effects in recognition memory were investigated with Type-2 signal detection receiver operating characteristic (ROC) analysis, which provides a measure of metacognitive monitoring. Experiment 1 demonstrated a frequency-based mirror effect, with a higher hit rate and lower false alarm rate, for low frequency words compared with high frequency words. In Experiment 2, the authors manipulated item strength with repetition, which showed an increased hit rate but no effect on the false alarm rate. Whereas Type-1 indices were ambiguous as to whether these effects were based on a criterion- or distribution-shift model, the two models predict opposite effects on Type-2 distractor monitoring under some assumptions. Hence, Type-2 ROC analysis discriminated between potential models of recognition that could not be discriminated using Type-1 indices alone. In Experiment 3, the authors manipulated Type-1 response bias by varying the number of old versus new response categories to confirm the assumptions made in Experiments 1 and 2. The authors conclude that Type-2 analyses are a useful tool for investigating recognition memory when used in conjunction with more traditional Type-1 analyses.

Avoidance of Timeout from Response-Independent Food: Effects of Delivery Rate and Quality

ERIC Educational Resources Information Center

Richardson, Joseph V.; Baron, Alan

2008-01-01

In three experiments, a rat's lever presses could postpone timeouts from food pellets delivered on response-independent schedules. In Experiment 1, the pellets were delivered at variable-time (VT) rates ranging from VT 0.5 to VT 8 min. Experiment 2 replicated the VT 1 min and VT 8 min conditions of Experiment 1 with new subjects. Finally, subjects…

Effects of an Introductory Letter on Response Rates to a Teen/Parent Telephone Health Survey

ERIC Educational Resources Information Center

Woodruff, Susan I.; Mayer, Joni A.; Clapp, Elizabeth

2006-01-01

The authors conducted a pilot study in preparation for a larger investigation that will rely on telephone surveys to assess select health behaviors of teens and their parents, with a focus on indoor tanning. This study used a randomized design to assess the impact of a presurvey letter on response rates to a telephone survey, as well as prevalence…

Effects of small-dose dexmedetomidine on hyperdynamic responses to electroconvulsive therapy.

PubMed

Li, Xiang; Tan, Fang; Jian, Chao-Jun; Guo, Na; Zhong, Zhi-Yong; Hei, Zi-Qing; Zhou, Shao-Li

2017-08-01

Acute hemodynamic responses to electroconvulsive therapy (ECT) may increase the risk of cardiovascular complications in vulnerable patients. The aim of the current study was to assess the effect of small-dose dexmedetomidine on hyperdynamic responses to ECT. Seventy-eight patients were enrolled and randomly allocated to receive either 0.2 μg/kg dexmedetomidine (Dex group, n = 39) or saline (Control group, n = 39) prior to ECT. Heart rate (HR) and mean arterial pressure (MAP) were recorded immediately after the administration of dexmedetomidine (T1), and 0, 1, 3, 5 and 10 min after the electrical stimuli ended (T2, T3, T4, T5 and T6). In addition, the peak HR after ECT, seizure duration, recovery time, and incidence rates of post-ECT adverse effects (agitation, headache and nausea) were also recorded. HR and MAP in the Dex group were significantly lower than those in the Control group from T2 to T5. In addition, peak HR was significantly lower in the Dex group compared with that in the Control group. Seizure length and time to spontaneous breathing, eye opening, and obeying commands in the Dex group were similar to those in the Control group. The incidence rates of post-ECT agitation and headache in the Dex group were significantly lower than that in the Control group. The administration of 0.2 μg/kg dexmedetomidine to patients receiving ECT leads to a significant reduction in HR, MAP, and peak HR responses to ECT without altering seizure duration or delaying recovery. Furthermore, dexmedetomidine effectively reduced the incidence rates of post-ECT adverse effects such as agitation and headache. Copyright © 2017. Published by Elsevier Taiwan LLC.

Which are the most important parameters for modelling carbon assimilation in boreal Norway spruce under elevated [CO(2)] and temperature conditions?

PubMed

Hall, Marianne; Medlyn, Belinda E; Abramowitz, Gab; Franklin, Oskar; Räntfors, Mats; Linder, Sune; Wallin, Göran

2013-11-01

Photosynthesis is highly responsive to environmental and physiological variables, including phenology, foliage nitrogen (N) content, atmospheric CO2 concentration ([CO2]), irradiation (Q), air temperature (T) and vapour pressure deficit (D). Each of these responses is likely to be modified by long-term changes in climatic conditions such as rising air temperature and [CO2]. When modelling photosynthesis under climatic changes, which parameters are then most important to calibrate for future conditions? To assess this, we used measurements of shoot carbon assimilation rates and microclimate conditions collected at Flakaliden, northern Sweden. Twelve 40-year-old Norway spruce trees were enclosed in whole-tree chambers and exposed to elevated [CO2] and elevated air temperature, separately and in combination. The treatments imposed were elevated temperature, +2.8 °C in July/August and +5.6 °C in December above ambient, and [CO2] (ambient CO2 ∼370 μ mol mol(-1), elevated CO2 ∼700 μ mol mol(-1)). The relative importance of parameterization of Q, T and D responses for effects on the photosynthetic rate, expressed on a projected needle area, and the annual shoot carbon uptake was quantified using an empirical shoot photosynthesis model, which was developed and fitted to the measurements. The functional form of the response curves was established using an artificial neural network. The [CO2] treatment increased annual shoot carbon (C) uptake by 50%. Most important was effects on the light response curve, with a 67% increase in light-saturated photosynthetic rate, and a 52% increase in the initial slope of the light response curve. An interactive effect of light saturated photosynthetic rate was found with foliage N status, but no interactive effect for high temperature and high CO2. The air temperature treatment increased the annual shoot C uptake by 44%. The most important parameter was the seasonality, with an elongation of the growing season by almost 4 weeks. The temperature response curve was almost flat over much of the temperature range. A shift in temperature optimum had thus an insignificant effect on modelled annual shoot C uptake. The combined temperature and [CO2] treatment resulted in a 74% increase in annual shoot C uptake compared with ambient conditions, with no clear interactive effects on parameter values.

Heart rate stress response dampening: the impact of alcohol, family history, and gender on at risk children and siblings.

PubMed

Croissant, Bernhard; Demmel, Ralf; Rist, Fred; Olbrich, Robert

2011-04-01

In the following study we tested the stress response dampening (SRD) model which postulates that stress responses are more likely to be attenuated by alcohol in individuals at risk for alcohol dependence than in persons without that risk. In a laboratory experiment we examined a) if SRD effects exist for both sons and healthy daughters of alcohol dependent fathers, and b) if SRD effects exist for siblings of alcohol dependent males. We recruited 104 subjects at risk and 51 matched control subjects. In a laboratory experiment, study subjects received alcohol in one of two laboratory sessions and a stress paradigm served to elicit heart rate stress responses. Heart rate stress responses were attenuated by alcohol in female family history positive (FHP) and female family history negative (FHN) subjects, however not in males. A multiple regression analysis revealed "Heart Rate Stress Response in the Non-Alcohol Condition" and "Blood Alcohol Level" as significant predictors of SRD. According to our findings, females carry a distinct risk for developing alcohol dependence, regardless of their family history and regardless of their degree of familial relationship. This is an important issue for devising models concerning the development and maintenance of alcohol dependence in females. The study extends the current research literature, which mainly focuses on male subjects at risk, by including female subjects at risk, as well as siblings at risk of both genders. Copyright © 2011 Elsevier B.V. All rights reserved.

Asymmetry in the control of cardiac performance by dorsomedial hypothalamus.

PubMed

Xavier, Carlos Henrique; Beig, Mirza Irfan; Ianzer, Danielle; Fontes, Marco Antônio Peliky; Nalivaiko, Eugene

2013-04-15

Dorsomedial hypothalamus (DMH) plays a key role in integrating cardiovascular responses to stress. We have recently reported greater heart rate responses following disinhibition of the right side of the DMH (R-DMH) in anesthetized rats and greater suppression of stress-induced tachycardia following inhibition of the R-DMH in conscious rats [both compared with similar intervention in the left DMH (L-DMH)], suggesting existence of right/left side asymmetry in controlling cardiac chronotropic responses by the DMH. The aim of the present study was to determine whether similar asymmetry is present for controlling cardiac contractility. In anesthetized rats, microinjections of the GABAA antagonist bicuculline methiodide (BMI; 40 pmol/100 nl) into the DMH-evoked increases in heart rate (HR), left ventricular pressure (LVP), myocardial contractility (LVdP/dt), arterial pressure, and respiratory rate. DMH disinhibition also precipitated multiple ventricular and supraventricular ectopic beats. DMH-induced increases in HR, LVP, LVdP/dt, and in the number of ectopic beats dependent on the side of stimulation, with R-DMH provoking larger responses. In contrast, pressor and respiratory responses did not depend on the side of stimulation. Newly described DMH-induced inotropic responses were rate-, preload- and (largely) afterload-independent; they were mediated by sympathetic cardiac pathway, as revealed by their sensitivity to β-adrenergic blockade. We conclude that recruitment of DMH neurons causes sympathetically mediated positive chronotropic and inotropic effects, and that there is an asymmetry, at the level of the DMH, in the potency to elicit these effects, with R-DMH > L-DMH.

The role of optoelectronic feedback on Franz-Keldysh voltage modulation of transistor lasers

NASA Astrophysics Data System (ADS)

Chang, Chi-Hsiang; Chang, Shu-Wei; Wu, Chao-Hsin

2016-03-01

Possessing both the high-speed characteristics of heterojunction bipolar transistors (HBTs) and enhanced radiative recombination of quantum wells (QWs), the light-emitting transistor (LET) which operates in the regime of spontaneous emissions has achieved up to 4.3 GHz modulation bandwidth. A 40 Gbit/s transmission rate can be even achieved using transistor laser (TL). The transistor laser provides not only the current modulation but also direct voltage-controlled modulation scheme of optical signals via Franz-Keldysh (FK) photon-assisted tunneling effect. In this work, the effect of FK absorption on the voltage modulation of TLs is investigated. In order to analyze the dynamics and optical responses of voltage modulation in TLs, the conventional rate equations relevant to diode lasers (DLs) are first modified to include the FK effect intuitively. The theoretical results of direct-current (DC) and small-signal alternating-current (AC) characteristics of optical responses are both investigated. While the DC characteristics look physical, the intrinsic optical response of TLs under the FK voltage modulation shows an AC enhancement with a 20 dB peak, which however is not observed in experiment. A complete model composed of the intrinsic optical transfer function and an electrical transfer function fed back by optical responses is proposed to explain the behaviors of voltage modulation in TLs. The abnormal AC peak disappears through this optoelectronic feedback. With the electrical response along with FK-included photon-carrier rate equations taken into account, the complete voltage-controlled optical modulation response of TLs is demonstrated.

The influence of the diffusion of responsibility effect on outcome evaluations: electrophysiological evidence from an ERP study.

PubMed

Li, Peng; Jia, Shiwei; Feng, Tingyong; Liu, Qiang; Suo, Tao; Li, Hong

2010-10-01

Previous studies have revealed that personal responsibility has an influence on outcome evaluation, although the way this influence works is still unclear. This study imitated the phenomenon of responsibility diffusion in a laboratory to examine the influence of the effect of responsibility diffusion on the processing of outcome evaluation using the event-related potential (ERP) technique. Participants of the study were required to perform the gambling task individually in the high-responsibility condition and with others in the low-responsibility scenario. Self-rating results showed that the participants felt more responsible for monetary loss and believed that they had more contributions to the monetary gains in the high-responsibility condition than in the low-responsibility situation. Both the feedback-related negativity (FRN) and the P300 were sensitive to the responsibility level, as evidenced by the enhanced amplitudes in the high-responsibility condition for both components. Further correlation analysis showed a negative correlation between FRN amplitudes and subjective rating scores (i.e., the higher the responsibility level, the larger the FRN amplitude). The results probably indicate that the FRN and P300 reflect personal responsibility processing under the social context of diffusion of responsibility. Copyright 2010 Elsevier Inc. All rights reserved.

Effect of manipulating recombination rates on response to selection in livestock breeding programs.

PubMed

Battagin, Mara; Gorjanc, Gregor; Faux, Anne-Michelle; Johnston, Susan E; Hickey, John M

2016-06-22

In this work, we performed simulations to explore the potential of manipulating recombination rates to increase response to selection in livestock breeding programs. We carried out ten replicates of several scenarios that followed a common overall structure but differed in the average rate of recombination along the genome (expressed as the length of a chromosome in Morgan), the genetic architecture of the trait under selection, and the selection intensity under truncation selection (expressed as the proportion of males selected). Recombination rates were defined by simulating nine different chromosome lengths: 0.10, 0.25, 0.50, 1, 2, 5, 10, 15 and 20 Morgan, respectively. One Morgan was considered to be the typical chromosome length for current livestock species. The genetic architecture was defined by the number of quantitative trait variants (QTV) that affected the trait under selection. Either a large (10,000) or a small (1000 or 500) number of QTV was simulated. Finally, the proportions of males selected under truncation selection as sires for the next generation were equal to 1.2, 2.4, 5, or 10 %. Increasing recombination rate increased the overall response to selection and decreased the loss of genetic variance. The difference in cumulative response between low and high recombination rates increased over generations. At low recombination rates, cumulative response to selection tended to asymptote sooner and the genetic variance was completely eroded. If the trait under selection was affected by few QTV, differences between low and high recombination rates still existed, but the selection limit was reached at all rates of recombination. Higher recombination rates can enhance the efficiency of breeding programs to turn genetic variation into response to selection. However, to increase response to selection significantly, the recombination rate would need to be increased 10- or 20-fold. The biological feasibility and consequences of such large increases in recombination rates are unknown.

The placebo effect.

PubMed

Margo, C E

1999-01-01

Placebos have been traditionally regarded as deceptive therapies and have not been understood in the broader context of social symbols and of interpersonal factors that surround the healing process itself. Although the power of inert substances to heal is well recognized, the placebo effect also influences the outcome of conventional therapies. The role of the placebo in modern medicine is poorly defined because of a lack of a common understanding of what the placebo effect is and because of the negative connotions associated with its use. The response rate to placebo varies by illness. The natural course of disease and patient or physician bias can be misinterpreted as a placebo response. In research, the placebo effect is therapeutic noise to be removed by placebo-controlled trials. Few studies are designed to measure the placebo response rate directly. Placebos are a reminder of how little is known about mind-body interaction. The placebo effect may be one of the most versatile and underused therapeutic tools at the disposal of physicians.

Does food availability affect energy expenditure rates of nesting seabirds? A supplemental-feeding experiment with Black-Legged Kittiwakes (Rissa tridactyla)

USGS Publications Warehouse

Jodice, Patrick G.R.; Roby, Daniel D.; Hatch, Scott A.; Gill, Verena A.; Lanctot, Richard B.; Visser, G. Henk

2002-01-01

We used a supplemental-feeding experiment, the doubly labeled water technique, and a model-selection approach based upon the Akaike Information Criterion to examine effects of food availability on energy expenditure rates of Black-legged Kittiwakes (Rissa tridactyla) raising young. Energy expenditure rates of supplementally fed females (n = 14) and males (n = 16) were 34 and 20% lower than those of control females (n = 14) and males (n = 18), respectively. Energy expenditure rates of females were more responsive to fluctuations in food availability than those of males. Fed males likely expended more energy while off the nest than fed females, possibly because of nest defense. Energy expenditure rates of fed kittiwakes were similar to values reported for kittiwakes that were either not raising young or not foraging. Parent kittiwakes, therefore, adjusted parental effort in response to variation in breeding conditions due to changes in food availability. Adjustments in reproductive effort in response to variable foraging conditions may have significant effects on the survival and productivity of individuals, and thus provide substantial fitness benefits for long-lived seabirds such as Black-legged Kittiwakes.

Behavioural and physiological responses of limpet prey to a seastar predator and their transmission to basal trophic levels.

PubMed

Manzur, Tatiana; Vidal, Francisco; Pantoja, José F; Fernández, Miriam; Navarrete, Sergio A

2014-07-01

Besides the well-documented behavioural changes induced by predators on prey, predator-induced stress can also include a suite of biochemical, neurological and metabolic changes that may represent important energetic costs and have long-lasting effects on individuals and on the demography of prey populations. The rapid transmission of prey behavioural changes to lower trophic levels, usually associated with alteration of feeding rates, can substantially change and even reverse direction over the long term as prey cope with the energetic costs associated with predation-induced stress. It is therefore critical to evaluate different aspects and assess the costs of non-consumptive predator effects on prey. We investigated the behavioural and physiological responses of an herbivorous limpet, Fissurella limbata, to the presence of chemical cues and direct non-lethal contact by the common seastar predator, Heliaster helianthus. We also evaluated whether the limpets feeding behaviour was modified by the predator and whether this translated into positive or negative effects on biomass of the green alga, Ulva sp. Our experimental results show the presence of Heliaster led to increased movement activity, increased distances travelled, changes in time budget over different environmental conditions and increased feeding rate in the keyhole limpets. Moreover, additional experiments showed that, beyond the increased metabolic rate associated with limpet increased activity, predator chemical cues heighten metabolic rate as part of the induced stress response. Changes in individual movement and displacement distances observed through the 9-day experiment can be interpreted as part of the escape response exhibited by limpets to reduce the risk of being captured by the predator. Increased limpet feeding rate on algae can be visualized as a way individuals compensate for the elevated energetic costs of movement and heightened metabolic rates produced by the predator-induced stress, which can lead to negative effects on abundance of the lower trophic level. We suggest that in order to understand the total non-consumptive effect of predators in natural communities, it is necessary to evaluate not only short-term behavioural responses, but also the costs associated with the multiple interdependent pathways triggered by predator-induced stress, and determine how individuals cope with these costs in the long term. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

Punishment and the potential for negative reinforcement with histamine injection.

PubMed

Mayer, Paulo César Morales; de Carvalho Neto, Marcus Bentes; Katz, Jonathan L

2018-03-01

The present study examined punishment of responding with histamine injection, and its potential to generate avoidance of punishment. Sprague-Dawley rats were trained under concurrent schedules in which responses on one lever (the punishment lever) produced food under a variable-interval schedule, and under some conditions intermittent injections of histamine, which suppressed behavior. Responses on a second (avoidance) lever prevented histamine injections scheduled on the punishment lever. After stabilization of punished responding, a variable-interval 15-s schedule of cancellation of histamine (avoidance) was added for responding on the second/avoidance lever, without subsequent acquisition of responding on that lever. Progressive decreases in the length of the punishment variable-interval schedule increased suppression on the punishment lever without increases in response rates on the avoidance lever. Exchanging contingencies on the levers ensured that response rates on the avoidance lever were sufficiently high to decrease the histamine injection frequency; nonetheless response rates on the avoidance lever decreased over subsequent sessions. Under no condition was responding maintained on the avoidance lever despite continued punishing effectiveness of histamine throughout. The present results suggest that avoidance conditioning is not a necessary condition for effective punishment, and confirm the importance of empirical rather than presumed categorization of behavioral effects of stimulus events. Published 2018. This article is a U.S. Government work and is in the public domain in the USA.

Predicting Effects of Coastal Acidification on Marine Bivalve ...

EPA Pesticide Factsheets

The partial pressure of carbon dioxide (pCO2) is increasing in the oceans and causing changes in seawater pH commonly described as ocean or coastal acidification. It is now well-established that, when reproduced in laboratory experiments, these increases in pCO2 can reduce survival and growth of early life stage bivalves. However, the effects that these impairments would have on whole populations of bivalves are unknown. In this study, these laboratory responses were incorporated into field-parameterized population models to assess population-level sensitivities to acidification for two northeast bivalve species with different life histories: Mercenaria mercenaria (hard clam) and Argopecten irradians (bay scallop). The resulting models permitted translation of laboratory pCO2 response functions into population-level responses to examine population sensitivity to future pCO2 changes. Preliminary results from our models indicate that if the current M. mercenaria negative population growth rate was attributed to the effects of pCO2 on early life stages, the population would decline at a rate of 50% per ten years at 420 microatmospheres (µatm) pCO2. If the current population growth rate was attributed to other additive factors (e.g., harvest, harmful algal blooms), M. mercenaria populations were predicted to decline at a rate of 50% per ten years at the preliminary estimate of 1010 µatm pCO2. The estimated population growth rate was positive for A. irradians,

Effects of active recovery on autonomic and haemodynamic responses after aerobic exercise.

PubMed

Soares, Antonio H G; Oliveira, Tiago P; Cavalcante, Bruno R; Farah, Breno Q; Lima, Aluísio H R A; Cucato, Gabriel G; Cardoso, Crivaldo G; Ritti-Dias, Raphael M

2017-01-01

The aim of this study was to examine the effect of active recovery on autonomic and haemodynamic responses after exercise in healthy adults. Nineteen healthy young male individuals underwent two experimental sessions: exercise with active recovery (AR) and exercise with passive recovery (PR). The exercise sessions comprised three phases: warm-up (5 min), exercise phase (cycle ergometer, 30 min, intensity between 60 and 70% of the heart rate reserve) and recovery (5 min). In the AR, the subjects remained cycling in the recovery phase at intensity between 30% and 35% of heart rate reserve, while in the PR, the subjects stopped the exercise after finishing the exercise phase. Blood pressure and heart rate were measured before and over the 30 min after the interventions. There were no differences for systolic and diastolic blood pressures, heart rate and rate pressure product between active and passive recovery sessions. Also, all heart rate variability parameters changed similarly after exercise with passive or active recovery sessions. In summary, exercise with active recovery does not affect the autonomic and haemodynamic responses after moderate-intensity aerobic exercise in healthy young male individuals. © 2015 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

Efficacy and safety of Ding-Kun-Dan for female infertility patients with predicted poor ovarian response undergoing in vitro fertilization/intracytoplasmic sperm injection: study protocol for a randomized controlled trial.

PubMed

Ma, Saihua; Ma, Ruihong; Xia, Tian; Afnan, Masoud; Song, Xueru; Xu, Fengqin; Hao, Guimin; Zhu, Fangfang; Han, Jingpei; Zhao, Zhimei

2018-02-20

Women undergoing in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) who have a predicted poor ovarian response (POR) present a challenge for reproductive medicine specialists. Traditional Chinese medicine (TCM) is commonly used in China for such patients, in the belief that it will improve the ovarian response and ultimately increase pregnancy rates. However, there is a lack of high-quality evidence about the effect of TCM on improving ovarian response in such patients. The purpose of this study is to evaluate ongoing viable pregnancy rate at 12 weeks' gestation and related indicators of ovarian response in fertile women who have a predicted poor ovarian response having immediate versus delayed IVF/ICSI after 3 months of Ding-Kun-Dan (DKD) pre-treatment. This study is a multicenter, randomized controlled, parallel-group, phase III, superiority clinical trial. Two hundred and seventy-eight eligible female infertility patients with POR will be included in the study and randomly allocated into an immediate treatment group and a DKD group in a 1:1 ratio. Both groups will receive IVF or ICSI as a standard treatment while in the DKD group, a commercially available Chinese medicine, DKD, will be administrated for 3 months before the IVF/ICSI cycle starts. The primary outcome of the study is the ongoing pregnancy rate at 12 weeks' gestation. The secondary outcomes include total gonadotropin dosage, duration of stimulation, estradiol (E 2 ) and progesterone (P) levels on human chorionic gonadotropin (hCG) trigger day, cycle cancellation rate, number of oocytes retrieved, high-quality embryo rate, biochemical pregnancy rate, the change of serum anti-Müllerian hormone (AMH), follicle-stimulating hormone (FSH), and E 2 levels and all side effects, safety outcomes, and any adverse events. The protocol was approved by the Ethics Committee of the First Teaching Hospital of Tianjin university of TCM (approval no. TYLL2017[K] 004). IVF/ICSI is increasingly used to treat couples desiring a baby. Many of these women will have poor ovarian function. In China, DKD is commonly used for these patients prior to undergoing IVF/ICSI. There is no effective treatment for poor ovarian response in Western medicine currently. It is important, therefore, to undertake this randomized control trial to determine whether DKD is effective or not. Chinese Clinical Trial Registry, ID: ChiCTR-IOR-17011697 . Registered on 19 June 2017.

What affects response rates in primary healthcare-based programmes? An analysis of individual and unit-related factors associated with increased odds of non-response based on HCV screening in the general population in Poland

PubMed Central

Parda, Natalia; Stępień, Małgorzata; Zakrzewska, Karolina; Madaliński, Kazimierz; Kołakowska, Agnieszka; Godzik, Paulina; Rosińska, Magdalena

2016-01-01

Objectives Response rate in public health programmes may be a limiting factor. It is important to first consider their delivery and acceptability for the target. This study aimed at determining individual and unit-related factors associated with increased odds of non-response based on hepatitis C virus screening in primary healthcare. Design Primary healthcare units (PHCUs) were extracted from the Register of Health Care Centres. Each of the PHCUs was to enrol adult patients selected on a random basis. Data on the recruitment of PHCUs and patients were analysed. Multilevel modelling was applied to investigate individual and unit-related factors associated with non-response. Multilevel logistic model was developed with fixed effects and only a random intercept for the unit. Preliminary analysis included a random effect for unit and each of the individual or PHCU covariates separately. For each of the PHCU covariates, we applied a two-level model with individual covariates, unit random effect and a single fixed effect of this unit covariate. Setting This study was conducted in primary care units in selected provinces in Poland. Participants A total of 242 PHCUs and 24 480 adults were invited. Of them, 44 PHCUs and 20 939 patients agreed to participate. Both PHCUs and patients were randomly selected. Results Data on 44 PHCUs and 24 480 patients were analysed. PHCU-level factors and recruitment strategies were important predictors of non-response. Unit random effect was significant in all models. Larger and private units reported higher non-response rates, while for those with a history of running public health programmes the odds of non-response was lower. Proactive recruitment, more working hours devoted to the project and patient resulted in higher acceptance of the project. Higher number of personnel had no such effect. Conclusions Prior to the implementation of public health programme, several factors that could hinder its execution should be addressed. PMID:27927665

What affects response rates in primary healthcare-based programmes? An analysis of individual and unit-related factors associated with increased odds of non-response based on HCV screening in the general population in Poland.

PubMed

Parda, Natalia; Stępień, Małgorzata; Zakrzewska, Karolina; Madaliński, Kazimierz; Kołakowska, Agnieszka; Godzik, Paulina; Rosińska, Magdalena

2016-12-07

Response rate in public health programmes may be a limiting factor. It is important to first consider their delivery and acceptability for the target. This study aimed at determining individual and unit-related factors associated with increased odds of non-response based on hepatitis C virus screening in primary healthcare. Primary healthcare units (PHCUs) were extracted from the Register of Health Care Centres. Each of the PHCUs was to enrol adult patients selected on a random basis. Data on the recruitment of PHCUs and patients were analysed. Multilevel modelling was applied to investigate individual and unit-related factors associated with non-response. Multilevel logistic model was developed with fixed effects and only a random intercept for the unit. Preliminary analysis included a random effect for unit and each of the individual or PHCU covariates separately. For each of the PHCU covariates, we applied a two-level model with individual covariates, unit random effect and a single fixed effect of this unit covariate. This study was conducted in primary care units in selected provinces in Poland. A total of 242 PHCUs and 24 480 adults were invited. Of them, 44 PHCUs and 20 939 patients agreed to participate. Both PHCUs and patients were randomly selected. Data on 44 PHCUs and 24 480 patients were analysed. PHCU-level factors and recruitment strategies were important predictors of non-response. Unit random effect was significant in all models. Larger and private units reported higher non-response rates, while for those with a history of running public health programmes the odds of non-response was lower. Proactive recruitment, more working hours devoted to the project and patient resulted in higher acceptance of the project. Higher number of personnel had no such effect. Prior to the implementation of public health programme, several factors that could hinder its execution should be addressed. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Effect of Forewarning on Emotional Responses to a Horror Film.

ERIC Educational Resources Information Center

Cantor, Joanne; And Others

1984-01-01

Describes a study which used the heart rate of subjects as the measure of physiological arousal to assess the effect of forewarning on emotional reactions and physiological responses to a frightening television film. Results indicate that although forewarning did not significantly affect anxiety, it did promote more intense fright and upset. (MBR)

SU-E-J-274: Responses of Medulloblastoma Cells to Radiation Dosimetric Parameters in Intensity-Modulated Radiation Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Park, J; Molecular Imaging Program at Stanford, Stanford, CA; Bio-X Program, Stanford, CA

2015-06-15

Purpose: To evaluate radiation responses of the medulloblastoma cell line Daoy in intensity-modulated radiation therapy (IMRT), quantitative variations to variable radiation dosimetic parameters were tracked by bioluminescent images (BLIs). Methods: The luciferase and green fluorescent protein positive Daoy cells were cultured on dishes. The medulloblastoma cells irradiated to different dose rate, interval of fractionated doses, field margin and misalignment, and dose uniformity in IMRT were monitored using bioluminescent images. The cultured cells were placed into a dedicated acrylic phantom to deliver intensity-modulated fluences and calculate accurate predicted dose distribution. The radiation with dose rate from 0.5 Gy/min to 15 Gy/minmore » was irradiated by adjusting monitor unit per minute and source-to-surface distances. The intervals of fractionated dose delivery were changed considering the repair time of double strand breaks (DSB) revealed by straining of gamma-H2AX.The effect of non-uniform doses on the cells were visualized by registering dose distributions and BLIs. The viability according to dosimetric parameters was correlated with bioluminescent intensities for cross-check of radiation responses. Results: The DSB and cell responses due to the first fractionated dose delivery significantly affected final tumor control rather than other parameters. The missing tumor volumes due to the smaller field margin than the tumor periphery or field misalignment caused relapse of cell responses on BLIs. The dose rate and gradient had effect on initial responses but could not bring out the distinguishable killing effect on cancer cells. Conclusion: Visualized and quantified bioluminescent images were useful to correlate the dose distributions with spatial radiation effects on cells. This would derive the effective combination of dose delivery parameters and fractionation. Radiation responses in particular IMRT configuration could be reflected to image based-dose re-optimization.« less

Changes in auditory nerve responses across the duration of sinusoidally amplitude-modulated electric pulse-train stimuli.

PubMed

Hu, Ning; Miller, Charles A; Abbas, Paul J; Robinson, Barbara K; Woo, Jihwan

2010-12-01

Response rates of auditory nerve fibers (ANFs) to electric pulse trains change over time, reflecting substantial spike-rate adaptation that depends on stimulus parameters. We hypothesize that adaptation affects the representation of amplitude-modulated pulse trains used by cochlear prostheses to transmit speech information to the auditory system. We recorded cat ANF responses to sinusoidally amplitude-modulated (SAM) trains with 5,000 pulse/s carriers. Stimuli delivered by a monopolar intracochlear electrode had fixed modulation frequency (100 Hz) and depth (10%). ANF responses were assessed by spike-rate measures, while representation of modulation was evaluated by vector strength (VS) and the fundamental component of the fast Fourier transform (F(0) amplitude). These measures were assessed across the 400 ms duration of pulse-train stimuli, a duration relevant to speech stimuli. Different stimulus levels were explored and responses were categorized into four spike-rate groups to assess level effects across ANFs. The temporal pattern of rate adaptation to modulated trains was similar to that of unmodulated trains, but with less rate adaptation. VS to the modulator increased over time and tended to saturate at lower spike rates, while F(0) amplitude typically decreased over time for low driven rates and increased for higher driven rates. VS at moderate and high spike rates and degree of F(0) amplitude temporal changes at low and moderate spike rates were positively correlated with the degree of rate adaptation. Thus, high-rate carriers will modify the ANF representation of the modulator over time. As the VS and F(0) measures were sensitive to adaptation-related changes over different spike-rate ranges, there is value in assessing both measures.

IIVP salvage regimen induces high response rates in patients with relapsed lymphoma before autologous stem cell transplantation.

PubMed

Abali, Huseyin; Oyan, Basak; Koc, Yener; Kars, Ayse; Barista, Ibrahim; Uner, Aysegul; Turker, Alev; Demirkazik, Figen; Tekin, Fatma; Tekuzman, Gulten; Kansu, Emin

2005-06-01

Patients with relapsed lymphoma can be cured with high-dose chemotherapy and autologous hematopoietic stem cell transplantation (HSCT). New therapeutic approaches with better cytoreductive capacity are needed for relapsed patients to keep their chance for cure with transplantation. We report 30 patients with relapsed lymphoma, median age 43 years, treated with IIVP salvage regimen consisting of ifosfamide, mesna, idarubicin, and etoposide for 2 or 3 cycles. Seventeen patients had non-Hodgkin lymphoma (NHL) and 13 patients had Hodgkin disease (HD). Fourteen (47%) patients were at their first relapse. Overall response rate was 86.6% (n = 26) with 19 patients (63.3%) achieving complete response. Overall response rate was 92% in patients with HD and 82% in NHL. The most frequent side effects observed were grade III-IV neutropenia (87%) and thrombocytopenia (73%). IIVP regimen is a highly effective salvage therapy for patients with relapsed HD or NHL who are candidates for autologous HSCT. Close follow up is necessary because of the high incidence of grade III-IV hematologic toxicity.

Management of Adolescent Low-Risk Classical Hodgkin Lymphoma: Which Chemotherapy Backbone Gives the Best Chance of Omitting Radiotherapy Safely.

PubMed

Algiraigri, Ali H; Essa, Mohammed F

2016-03-01

Even though more than 90% of adolescents with low-risk classical Hodgkin lymphoma (LRcHL) will be cured with first-line therapy, many will suffer serious late toxic effects from radiotherapy (RT). The goals for care have shifted toward minimizing late toxic effects without compromising the outstanding cure rates by adapting a risk and response-based therapy. Recent published and ongoing randomized clinical trials, using functional imaging, may allow for better identification of those patients for whom RT may be safely omitted while maintaining excellent cure rates. To evaluate the best chemotherapy regimens with a reasonable toxicity profile and that are expected to have a high chance of omitting RT based on a response-directed therapy while maintaining high cure rates, a mini review was conducted of the recent clinical trials in pediatric and adult LRcHL. The UK RAPID trial chemotherapy backbone (3 × ABVD) followed by a response-based positron emission tomography scan offers up to a 75% chance of safely omitting RT without compromising the cure rate, which remained well above 90%.

Sample substitution can be an acceptable data-collection strategy: the case of the Belgian Health Interview Survey.

PubMed

Demarest, Stefaan; Molenberghs, Geert; Van der Heyden, Johan; Gisle, Lydia; Van Oyen, Herman; de Waleffe, Sandrine; Van Hal, Guido

2017-11-01

Substitution of non-participating households is used in the Belgian Health Interview Survey (BHIS) as a method to obtain the predefined net sample size. Yet, possible effects of applying substitution on response rates and health estimates remain uncertain. In this article, the process of substitution with its impact on response rates and health estimates is assessed. The response rates (RR)-both at household and individual level-according to the sampling criteria were calculated for each stage of the substitution process, together with the individual accrual rate (AR). Unweighted and weighted health estimates were calculated before and after applying substitution. Of the 10,468 members of 4878 initial households, 5904 members (RRind: 56.4%) of 2707 households (RRhh: 55.5%) participated. For the three successive (matched) substitutes, the RR dropped to 45%. The composition of the net sample resembles the one of the initial samples. Applying substitution did not produce any important distorting effects on the estimates. Applying substitution leads to an increase in non-participation, but does not impact the estimations.

Heart rate responses provide an objective evaluation of human disturbance stimuli in breeding birds.

PubMed

Ellenberg, Ursula; Mattern, Thomas; Seddon, Philip J

2013-01-01

Intuition is a poor guide for evaluating the effects of human disturbance on wildlife. Using the endangered Yellow-eyed penguin, Megadyptes antipodes, as an example, we show that heart rate responses provide an objective tool to evaluate human disturbance stimuli and encourage the wider use of this simple and low-impact approach. Yellow-eyed penguins are a flagship species for New Zealand's wildlife tourism; however, unregulated visitor access has recently been associated with reduced breeding success and lower first year survival. We measured heart rate responses of Yellow-eyed penguins via artificial eggs to evaluate a range of human stimuli regularly occurring at their breeding sites. We found the duration of a stimulus to be the most important factor, with elevated heart rate being sustained while a person remained within sight. Human activity was the next important component; a simulated wildlife photographer, crawling slowly around during his stay, elicited a significantly higher heart rate response than an entirely motionless human spending the same time at the same distance. Stimuli we subjectively might perceive as low impact, such as the careful approach of a 'wildlife photographer', resulted in a stronger response than a routine nest-check that involved lifting a bird up to view nest contents. A single, slow-moving human spending 20 min within 2 m from the nest may provoke a response comparable to that of 10 min handling a bird for logger deployment. To reduce cumulative impact of disturbance, any human presence in the proximity of Yellow-eyed penguins needs to be kept at a minimum. Our results highlight the need for objective quantification of the effects of human disturbance in order to provide a sound basis for guidelines to manage human activity around breeding birds.

[Effect of acoustic stimulus intensity on air-conducted sound elicited ocular vestibular-evoked myogenic potential and cervical vestibular-evoked myogenic potential].

PubMed

Zhang, Rui; Xu, Min; Zhang, Qing; Yang, Yin-Tong; Chen, Yanfei

2014-06-01

To observe the effect of acoustic stimulus intensity on air-conducted sound elicited ocular vestibular- evoked myogenic potential (oVEMP) and cervical vestibular-evoked myogenic potential (cVEMP) in normal young Chinese subjects. Thirty-five normal subjects aged 4-40 years (20.80∓8.89 years), including 16 males and 19 females, were recruited for conventional oVEMP and cVEMP examinations. The responses obtained from each side using 500 Hz tone bursts were divided into 6 groups according to different sound intensities (100, 95, 90, 85, 80 and 75dB nHL). The response rate and normal parameters of each stimulus intensity group were calculated. As the acoustic stimulus intensity decreased, the oVEMP response rate decreased from 100% in both 100 dB nHL and 95dB nHL groups to 97.14% (90 dB nHL), 54.29% (85 dB nHL), 14.29% (80 dB nHL), and 2.86% (75 dB nHL), and the response rate of cVEMP, 100% in both 100 dB nHL and 95dB nHL groups, was lowered to 97.14% (90 dB nHL), 84.29% (85 dB nHL), 38.57% (80 dB nHL) and 8.57% (75 dB nHL). The response rate and the parameters were comparable between 100 and 95 dB nHL groups. As the acoustic stimulus intensity decreases, both oVEMP and cVEMP show decreased response rate and amplitude. For Chinese subjects under 40 years of age, we recommend 95dB nHL as the maximum initial stimulus intensity in VEMPs test.

Response of the elderly to disaster: an age-stratified analysis.

PubMed

Bolin, R; Klenow, D J

This article analyzes the effects of chronological age of disaster victims on their responses to stress effects of natural disasters. Previous research is reviewed and major findings of that research are noted. Findings regarding disaster losses, physical impacts, aid utilization patterns, kinship relations, relative deprivation, social-psychological impacts, neglect of elderly disaster victims, and differential recovery rates by age are retested on new data. Data described herein were gathered using survey techniques in two disaster stricken communities in Texas. Elderly victims' responses to the tornadoes are compared to a nonelderly (under sixty years of age) group to assess differences. Findings of previous research were, in many instances, supported although certain divergences between the current findings and preceding findings are noted, particularly in rates of recovery.

Process optimization of rolling for zincked sheet technology using response surface methodology and genetic algorithm

NASA Astrophysics Data System (ADS)

Ji, Liang-Bo; Chen, Fang

2017-07-01

Numerical simulation and intelligent optimization technology were adopted for rolling and extrusion of zincked sheet. By response surface methodology (RSM), genetic algorithm (GA) and data processing technology, an efficient optimization of process parameters for rolling of zincked sheet was investigated. The influence trend of roller gap, rolling speed and friction factor effects on reduction rate and plate shortening rate were analyzed firstly. Then a predictive response surface model for comprehensive quality index of part was created using RSM. Simulated and predicted values were compared. Through genetic algorithm method, the optimal process parameters for the forming of rolling were solved. They were verified and the optimum process parameters of rolling were obtained. It is feasible and effective.

Assessing potency of high- and low-preference reinforcers with respect to response rate and response patterns.

PubMed

Penrod, Becky; Wallace, Michele D; Dyer, Edwin J

2008-01-01

Previous research has suggested that the availability of high-preference stimuli may override the reinforcing efficacy of concurrently available low-preference stimuli under relatively low schedule requirements (e.g., fixed-ratio 1 schedule). It is unknown if similar effects would be obtained under higher schedule requirements. Thus, the current study compared high-preference and low-preference reinforcers under progressively increasing schedule requirements. Results for 3 of the 4 participants indicated that high-preference stimuli maintained responding under higher schedule requirements relative to low-preference stimuli. For 1 participant, high-preference and low-preference stimuli were demonstrated to be equally effective reinforcers under increasing schedule requirements. Implications with respect to rate of performance and response patterns are discussed.

Relationships between direct predation and risk effects.

PubMed

Creel, Scott; Christianson, David

2008-04-01

Risk effects arise when prey alter their behavior in response to predators, and these responses carry costs. Empirical studies have found that risk effects can be large. Nonetheless, studies of predation in vertebrate conservation and management usually consider only direct predation. Given the ubiquity and strength of behavioral responses to predators by vertebrate prey, it is not safe to assume that risk effects on dynamics can be ignored. Risk effects can be larger than direct effects. Risk effects can exist even when the direct rate of predation is zero. Risk effects and direct effects do not necessarily change in parallel. When risk effects reduce reproduction rather than survival, they are easily mistaken for limitation by food supply.

Palliation by Low-Dose Local Radiation Therapy for Indolent Non-Hodgkin Lymphoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chan, Elisa K.; Fung, Sharon; Gospodarowicz, Mary

Purpose: The purpose of this study was to assess the efficacy of a 2 Multiplication-Sign 2 Gy (total dose, 4 Gy) palliative radiation therapy (RT) regimen for treating patients with indolent non-Hodgkin lymphoma (NHL) in terms of response rate, response duration, and symptom relief. Methods and Materials: A retrospective chart review was conducted. Between 2003 and 2007, 54 patients with NHL were treated to 85 anatomical sites with a 2 Multiplication-Sign 2 Gy palliative regimen. Local response was assessed by clinical and/or radiographic data. Symptoms before and after treatment for each site treated were obtained from clinical notes in patientmore » medical records. Median follow-up time was 1.3 years. Results: For the 54 patients, the median age at time of treatment was 71.1 years old, and 57% of them were male. Of the 85 disease sites treated, 56% of sites had indolent histology, 28% of sites were diagnosed with chronic lymphocytic leukemia (CLL), 13% of sites had aggressive histology, and 2% of sites were shown to have other histology. Overall response rate (ORR) was 81% (49% complete response [CR], 32% partial response [PR]). The 2-year rate for freedom from local progression was 50% (95% CI, 37%-61%). The ORR for follicular lymphoma, Mucosa associated lymphoid tissue (MALT), and marginal zone lymphoma (MZL) histology was 88%, compared with a 59% rate for CLL histology (p = 0.005). While the ORR was similar for tumors of different sizes, the CR rate for patients with tumors <5 cm tended to be higher than those with tumors >10 cm (CR rate of 57% vs. 27%, respectively; p = 0.06). For the 48 sites with clearly documented symptoms at pretreatment, 92% of sites improved after low-dose RT. Conclusions: Short-course low-dose palliative radiotherapy (2 Multiplication-Sign 2 Gy) is an effective treatment that results in high response rates for indolent non-Hodgkin lymphoma. This treatment regimen provides effective symptomatic relief for tumor bulk of all sizes.« less

Matching and Conditioned Reinforcement Rate

ERIC Educational Resources Information Center

Shahan, Timothy A.; Podlesnik, Christopher A.; Jimenez-Gomez, Corina

2006-01-01

Attempts to examine the effects of variations in relative conditioned reinforcement rate on choice have been confounded by changes in rates of primary reinforcement or changes in the value of the conditioned reinforcer. To avoid these problems, this experiment used concurrent observing responses to examine sensitivity of choice to relative…

Bilingual recognition memory: stronger performance but weaker levels-of-processing effects in the less fluent language.

PubMed

Francis, Wendy S; Gutiérrez, Marisela

2012-04-01

The effects of bilingual proficiency on recognition memory were examined in an experiment with Spanish-English bilinguals. Participants learned lists of words in English and Spanish under shallow- and deep-encoding conditions. Overall, hit rates were higher, discrimination greater, and response times shorter in the nondominant language, consistent with effects previously observed for lower frequency words. Levels-of-processing effects in hit rates, discrimination, and response time were stronger in the dominant language. Specifically, with shallow encoding, the advantage for the nondominant language was larger than with deep encoding. The results support the idea that memory performance in the nondominant language is impacted by both the greater demand for cognitive resources and the lower familiarity of the words.

Judged effectiveness of threat and coping appraisal anti-speeding messages.

PubMed

Cathcart, Rachel L; Glendon, A Ian

2016-11-01

Using a young driver sample, this experimental study sought to identify which combinations of threat-appraisal (TA) and coping-appraisal (CA) messages derived from protection motivation theory (PMT) participants would judge as most effective for themselves, and for other drivers. The criterion variable was reported intention to drive within a signed speed limit. All possible TA/CA combinations of 18 previously highly-rated anti-speeding messages were presented both simultaneously and sequentially. These represented PMT's three TA components: severity, vulnerability, and rewards, and three CA components: self-efficacy, response efficacy, and response costs. Eighty-eight young drivers (34 males) each rated 54 messages for perceived effectiveness for self and other drivers. Messages derived from the TA severity component were judged the most effective. Response cost messages were most effective for females. Reverse third-person effects were found for both females and males, which suggested that combining TA and CA components may increase the perceived relevance of anti-speeding messages for males. The findings have potential value for creating effective roadside anti-speeding messages, meriting further investigation in field studies. Copyright © 2016 Elsevier Ltd. All rights reserved.

Removing very low-performing therapists: A simulation of performance-based retention in psychotherapy

PubMed Central

Imel, Zac E.; Sheng, Elisa; Baldwin, Scott A.; Atkins, David C.

2016-01-01

Therapists can impact the likelihood a given patient will benefit from psychotherapy. However, therapists are rarely held accountable for their patients' outcomes. As a result, low performing providers likely continue to practice alongside providers with high response rates. In the current study, we conducted a Monte Carlo simulation to illustrate a thought experiment—what happens to patient outcomes if therapists with the worst outcomes were removed from practice? We drew initial samples of 50 therapists from three simulated populations of 1,000 therapists with a mean patient response rate of 50% and different effect sizes for therapist variability in outcomes. We simulated 30 patient outcomes for each therapist, with outcome defined as response to treatment versus no response. We removed therapists with response rates in the bottom 5% and replaced them with a random sample of therapists from the population. Over 10 years, the difference in responses between the lowest and highest performing therapists was substantial (between 697 and 997 additional responses to treatment). After repeatedly removing the lowest performing providers 40 times (simulating a 10 year time span), response rates increased substantially. The cumulative number of patient responses (i.e., summing the total number of responses across 10 years) increased by 4266, 6404, and 9307 when therapists accounted for 5%, 10%, or 20% of the patient outcome variance, respectively. These findings indicate that performance-based retention of therapists could improve the quality of psychotherapy in health systems by improving the average response rate and decreasing the probability that a patient will be treated by a therapist who has little chance of helping. PMID:26301424

Effect of honey versus sucrose on appetite, appetite-regulating hormones, and postmeal thermogenesis.

PubMed

Larson-Meyer, D Enette; Willis, Kentz S; Willis, Lindsey M; Austin, Kathleen J; Hart, Ann Marie; Breton, Ashley B; Alexander, Brenda M

2010-10-01

Increased per capita consumption of sweeteners may be responsible in part for the rising prevalence of obesity in the United States. Recent studies suggest that consumption of honey is not associated with this same obesogenic effect and may have beneficial effects neuro on body weight. The purpose of this study was to evaluate whether the meal-induced responses of ghrelin and peptide YY(3-36) (PYY(3-36)) and/or meal-induced thermogenesis differ following a honey- versus a sucrose-containing meal. In a double-blind randomly assigned study, appetite hormones (ghrelin, PYY(3-36), leptin) and glycemic and thermic responses were evaluated following isoglucidic ∼450 kcal honey- or sucrose-containing breakfasts in 14 healthy, nonobese women (22 ± 3 y). Blood samples and hunger ratings were obtained at baseline and every 30 minutes for 240 minutes following the meal. Meal-induced thermogenesis was measured by indirect calorimetry. Ad libitum food intake was evaluated from a free-choice meal following the test meal. Honey consumption delayed the postprandial ghrelin response (p = 0.037), enhanced the total PYY (p = 0.007) response, and blunted the glucose response (p = 0.039) compared with consumption of the sucrose-containing meal. Meal-induced insulin response, hunger ratings, thermogenesis, and subsequent ad libitum food intake, however, did not differ (p > 0.10) between diet treatments. Alterations in meal-induced responses of ghrelin and PYY(3-36) but not meal-induced thermogenesis may be responsible in part for the potential "obesity protective" effect(s) of honey consumption. A blunted glycemic response may be beneficial for reducing glucose intolerance. Further research is required to determine if these findings hold true for obese individuals, for males, or with habitual consumption.

Tolazoline decreases survival time during microwave-induced lethal heat stress in anesthetized rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jauchem, J.R.; Chang, K.S.; Frei, M.R.

1996-03-01

Effects of {alpha}-adrenergic antagonists have been studied during environmental heating but not during microwave-induced heating. Tolazoline may exert some of its effects via {alpha}-adrenergic blockade. In the present study, ketamine-anesthetized Sprague-Dawley rats were exposed to 2450-MHz microwaves at an average power density of 60 mW/cm{sup 2} (whole-body specific absorption rate of approximately 14 W/kg) until lethal temperatures were attained. The effects of tolazoline (10 mg/kg body weight) on physiological responses (including changes in body temperature, heart rate, blood pressure, and respiratory rate) were examined. Survival time was significantly shorter in the tolazoline group than in saline-treated animals. In general, heartmore » rate and blood pressure responses were similar to those that occur during environmental heat stress. Heart rate, however, was significantly elevated in animals that received tolazoline, both before and during terminal microwave exposure. It is possible that changes associated with the elevated heart rate (e.g., less cardiac filling) in tolazoline-treated animals resulted in greater susceptibility to microwave-induced heating and the lower survival time. 47 refs., 3 figs., 2 tabs.« less

Adoptive Cell Therapy for Patients With Metastatic Melanoma: Evaluation of Intensive Myeloablative Chemoradiation Preparative Regimens

PubMed Central

Dudley, Mark E.; Yang, James C.; Sherry, Richard; Hughes, Marybeth S.; Royal, Richard; Kammula, Udai; Robbins, Paul F.; Huang, JianPing; Citrin, Deborah E.; Leitman, Susan F.; Wunderlich, John; Restifo, Nicholas P.; Thomasian, Armen; Downey, Stephanie G.; Smith, Franz O.; Klapper, Jacob; Morton, Kathleen; Laurencot, Carolyn; White, Donald E.; Rosenberg, Steven A.

2008-01-01

Purpose The two approved treatments for patients with metastatic melanoma, interleukin (IL)-2 and dacarbazine, mediate objective response rates of 12% to 15%. We previously reported that adoptive cell therapy (ACT) with autologous antitumor lymphocytes in lymphodepleted hosts mediated objective responses in 51% of 35 patients. Here, we update that study and evaluate the safety and efficacy of two increased-intensity myeloablative lymphodepleting regimens. Patients and Methods We performed two additional sequential trials of ACT with autologous tumor-infiltrating lymphocytes (TIL) in patients with metastatic melanoma. Increasing intensity of host preparative lymphodepletion consisting of cyclophosphamide and fludarabine with either 2 (25 patients) or 12 Gy (25 patients) of total-body irradiation (TBI) was administered before cell transfer. Objective response rates by Response Evaluation Criteria in Solid Tumors (RECIST) and survival were evaluated. Immunologic correlates of effective treatment were studied. Results Although nonmyeloablative chemotherapy alone showed an objective response rate of 49%, when 2 or 12 Gy of TBI was added, the response rates were 52% and 72% respectively. Responses were seen in all visceral sites including brain. There was one treatment-related death in the 93 patients. Host lymphodepletion was associated with increased serum levels of the lymphocyte homeostatic cytokines IL-7 and IL-15. Objective responses were correlated with the telomere length of the transferred cells. Conclusion Host lymphodepletion followed by autologous TIL transfer and IL-2 results in objective response rates of 50% to 70% in patients with metastatic melanoma refractory to standard therapies. PMID:18809613

Mean field model of acetylcholine mediated dynamics in the cerebral cortex.

PubMed

Clearwater, J M; Rennie, C J; Robinson, P A

2007-12-01

A recent continuum model of the large scale electrical activity of the cerebral cortex is generalized to include cholinergic modulation. In this model, dynamic modulation of synaptic strength acts over the time scales of nicotinic and muscarinic receptor action. The cortical model is analyzed to determine the effect of acetylcholine (ACh) on its steady states, linear stability, spectrum, and temporal responses to changes in subcortical input. ACh increases the firing rate in steady states of the system. Changing ACh concentration does not introduce oscillatory behavior into the system, but increases the overall spectral power. Model responses to pulses in subcortical input are affected by the tonic level of ACh concentration, with higher levels of ACh increasing the magnitude firing rate response of excitatory cortical neurons to pulses of subcortical input. Numerical simulations are used to explore the temporal dynamics of the model in response to changes in ACh concentration. Evidence is seen of a transition from a state in which intracortical inputs are emphasized to a state where thalamic afferents have enhanced influence. Perturbations in ACh concentration cause changes in the firing rate of cortical neurons, with rapid responses due to fast acting facilitatory effects of nicotinic receptors on subcortical afferents, and slower responses due to muscarinic suppression of intracortical connections. Together, these numerical simulations demonstrate that the actions of ACh could be a significant factor modulating early components of evoked response potentials.

[Comparison of the Effectiveness and Safety of Combined Chemotherapy with PEG-Asp for Treatment of ALL and T-NHL Patients].

PubMed

Xu, Yan; Wang, Jin; Yang, Nan; Bai, Ju; Zhang, Peng-Yu; Gu, Liu-Fang; Lei, Bo; Liu, Jie; Wang, Fang-Xia; Huang, Bing-Qiao; Zhang, Wang-Gang; He, Ai-Li; Cao, Xing-Mei; Chen, Yin-Xia; Ma, Xiao-Rong

2016-04-01

To explore the effectiveness and safety of combined chemotherapy with pegasparaginase (PEG-Asp) for treatment of patients with acute lymphoblastic leukemia (ALL) and T cell non-Hodgkin's lymphoma (T-NHL) patients. A total of 62 ALL or T-NHL patients were diagnosed and treated in our department and were enrolled in this study. Among them, 22 patients received the combined chemotherapy with PEG-Asp, while the other 40 patients received the standard chemotherapy with L-asparaginase (L-Asp) as the control. Therapeutic effectiveness, adverse effects, duration and expense of hospitalization, treatment-related mortality and survival were evaluated and compared in 2 different groups. In group of combined chemotherapy with PEG-Asp, the overall response rate was 90.91% (20 cases), among them CR rate and PR rate are 77.27% (17 cases) and 13.64% (3 cases), respectively. In the group of standard chemotherapy with L-Asp, the overall response rate was 87.5% (35 cases), among them CR rate and PR rate were 72.5% (29 cases) and 15% (6 cases), respectively. The difference neither between PEG-Asp and L-Asp chemotherapy groups nor between ALL and T-NHL subgroups was significant (P > 0.05). The 6-month and 12-month overall survival rates were not significantly different between the PEG-Asp and L-Asp chemotherapy groups, respectively (P > 0.05). The adverse effects were identified as degree 1-2 according to the WHO criteria of drug toxicity. Neither the adverse effects identified as degree 3-4 nor the treatment-related death were observed. Expect for allergy and hyperglycaemia, the difference of side-effect incidence between the two groups were not significant (P > 0.05). The treatment for all the patients in PEG-Asp chemotherapy group was completed, while the treatment with L-Asp was completed only in 29 cases. Moreover, both average duration and expense of hospitalization after the combined chemotherapy were less than the control. With higher response rate, lower drug toxicity and allergy incidence, the combined chemotherapy with PEG-Asp can replace the standard chemotherapy with L-Asp in the treatment of ALL and T-NHL. The optimization of the combined chemotheropeutic protocols for more cases and long-term survival rates need to further and deeply explorate.

The effect of cortisol on emotional responses depends on order of cortisol and placebo administration in a within-subject design.

PubMed

Wirth, Michelle M; Scherer, Sean M; Hoks, Roxanne M; Abercrombie, Heather C

2011-08-01

Cortisol does not exhibit a straightforward relationship with mood states; administration of glucocorticoids to human subjects has produced mixed effects on mood and emotional processing. In this study, participants (N=46) received intravenous hydrocortisone (synthetic cortisol; 0.1mg/kg body weight) and placebo in randomized order over two sessions 48h apart. Following the infusion, participants rated neutral and unpleasant pictures. In Session 1, participants reported elevated negative affect (NA) following the picture-rating task, regardless of treatment. In Session 2, however, only participants who received cortisol (and thus who had received placebo in Session 1) reported elevated NA. Arousal ratings for unpleasant pictures followed a similar pattern. These findings suggest that the effects of cortisol on emotion vary based on situational factors, such as drug administration order or familiarity with the tasks and setting. Such factors can influence cortisol's effects on emotion in two ways: (A) cortisol may only potentiate NA and arousal ratings in the absence of other, overwhelming influences on affect, such as the novelty of the setting and tasks in Session 1; and (B) cortisol in Session 1 may facilitate learning processes (e.g., habituation to the stimuli and setting; extinction of aversive responses) such that emotional responses to the pictures are lessened in Session 2. This interpretation is compatible with a body of literature on the effects of glucocorticoids on learning and memory processes. Copyright © 2010 Elsevier Ltd. All rights reserved.

Electroacupuncture most effectively elicits depressor and bradycardic responses at 1 Hz in humans.

PubMed

Nakahara, Hidehiro; Kawada, Toru; Ueda, Shin-ya; Kawai, Eriko; Yamamoto, Hiromi; Sugimachi, Masaru; Miyamoto, Tadayoshi

2016-02-01

Acupuncture stimulation is known to act on the autonomic nervous system and elicits depressor and bradycardic effects. However, previous studies on humans did not conduct quantitative analyses on optimal acupuncture conditions such as the stimulation frequency and duration to achieve maximum depressor and bradycardic effects. The aim of the present study was to investigate the effects of varying stimulation frequencies of electroacupuncture on time-dependent changes in blood pressure and heart rate in humans. Twelve healthy volunteers participated in the study. An acupuncture needle was inserted at the Ximen acupoint (PC4 according to WHO nomenclature), located at the anterior aspect of the forearm. An electrical stimulation was delivered through the acupuncture needle at an intensity of 1 V, pulse width of 5 ms, and stimulation frequencies of 0.5, 1, 5, and 10 Hz in a random order. The duration of electroacupuncture was 6 min, during which blood pressure and heart rate responses were monitored. Group-averaged data indicated that 1-Hz electroacupuncture decreased blood pressure and heart rate. Blood pressure was significantly decreased from the prestimulation baseline value of 86.6 ± 2.9 to 81.4 ± 2.3 mmHg during 4-6 min of 1-Hz electroacupuncture (mean ± SE, P < 0.01). Heart rate was also significantly decreased (from 66.2 ± 2.0 to 62.7 ± 1.7 beats/min, P < 0.01). These results provide fundamental evidence that bradycardiac and depressor responses are effectively produced by electrical acupuncture in humans.

The effect of cortisol on emotional responses depends on order of cortisol and placebo administration in a within-subjects design

PubMed Central

Wirth, Michelle M.; Scherer, Sean M.; Hoks, Roxanne M.; Abercrombie, Heather C.

2010-01-01

Cortisol does not exhibit a straightforward relationship with mood states; administration of glucocorticoids to human subjects has produced mixed effects on mood and emotional processing. In this study, participants (N=46) received intravenous hydrocortisone (synthetic cortisol; 0.1 mg/kg body weight) and placebo in randomized order over two sessions 48 hours apart. Following the infusion, participants rated neutral and unpleasant pictures. In Session 1, participants reported elevated negative affect (NA) following the picture-rating task, regardless of treatment. In Session 2, however, only participants who received cortisol (and thus who had received placebo in Session 1) reported elevated NA. Arousal ratings for unpleasant pictures followed a similar pattern. These findings suggest that the effects of cortisol on emotion vary based on situational factors, such as drug administration order or familiarity with the tasks and setting. Such factors can influence cortisol’s effects on emotion in two ways: A) cortisol may only potentiate NA and arousal ratings in the absence of other, overwhelming influences on affect, such as the novelty of the setting and tasks in Session 1; and B) cortisol in Session 1 may facilitate learning processes (e.g. habituation to the stimuli and setting; extinction of aversive responses) such that emotional responses to the pictures are lessened in Session 2. This interpretation is compatible with a body of literature on the effects of glucocorticoids on learning and memory processes. PMID:21232874

Role of gamma-aminobutyric acid type A (GABAA) receptor subtypes in acute benzodiazepine physical dependence-like effects: evidence from squirrel monkeys responding under a schedule of food presentation

PubMed Central

Fischer, Bradford D.; Teixeira, Laura P.; van Linn, Michael L.; Namjoshi, Ojas A.; Cook, James M.; Rowlett, James K.

2013-01-01

Rationale Assays of schedule-controlled responding can be used to characterize the pharmacology of benzodiazepines and other GABAA receptor modulators, and are sensitive to changes in drug effects that are related to physical dependence. Objective The present study used this approach to investigate the role of GABAA receptor subtypes in mediating dependence-like effects following benzodiazepine administration. Methods Squirrel monkeys (n=6) were trained on a fixed-ratio schedule of food reinforcement. Initially, the response rate-decreasing effects of chlordiazepoxide (0.1–10 mg/kg; nonselective GABAA receptor agonist), zolpidem (0.032–1.0 mg/kg; α1 subunit-containing GABAA subtype-preferring agonist) and HZ-166 (0.1–10 mg/kg; functionally selective α2 and α3 subunit-containing GABAA receptor agonist) were assessed. Next, acute dependence-like effects following single injections of chlordiazepoxide, zolpidem and HZ-166 were assessed with flumazenil (0.1–3.2 mg/kg; nonselective GABAA receptor antagonist). Finally, acute dependence-like effects following zolpidem administration were assessed with βCCt and 3-PBC (0.1–3.2 mg/kg and 0.32–10 mg/kg, respectively; α1 subunit-containing GABAA receptor antagonists). Results Chlordiazepoxide, zolpidem and HZ-166 produced dose- and time-dependent decreases in response rates, whereas flumazenil, βCCt and 3-PBC were ineffective. After the drug effects waned, flumazenil produced dose-dependent decreases in response rates following administration of 10 mg/kg chlordiazepoxide and 1.0 mg/kg zolpidem, but not following any dose of HZ-166. Further, both βCCt and 3-PBC produced dose-dependent decreases in response rates when administered after 1.0 mg/kg zolpidem. Conclusions These data raise the possibility that α1 subunit-containing GABAA receptors play a major role in physical dependence-related behaviors following a single injection of a benzodiazepine. PMID:23354533

Role of gamma-aminobutyric acid type A (GABAA) receptor subtypes in acute benzodiazepine physical dependence-like effects: evidence from squirrel monkeys responding under a schedule of food presentation.

PubMed

Fischer, Bradford D; Teixeira, Laura P; van Linn, Michael L; Namjoshi, Ojas A; Cook, James M; Rowlett, James K

2013-05-01

Assays of schedule-controlled responding can be used to characterize the pharmacology of benzodiazepines and other GABAA receptor modulators, and are sensitive to changes in drug effects that are related to physical dependence. The present study used this approach to investigate the role of GABAA receptor subtypes in mediating dependence-like effects following benzodiazepine administration. Squirrel monkeys (n = 6) were trained on a fixed-ratio schedule of food reinforcement. Initially, the response rate-decreasing effects of chlordiazepoxide (0.1-10 mg/kg; nonselective GABAA receptor agonist), zolpidem (0.032-1.0 mg/kg; α1 subunit-containing GABAA subtype-preferring agonist), and HZ-166 (0.1-10 mg/kg; functionally selective α2 and α3 subunit-containing GABAA receptor agonist) were assessed. Next, acute dependence-like effects following single injections of chlordiazepoxide, zolpidem, and HZ-166 were assessed with flumazenil (0.1-3.2 mg/kg; nonselective GABAA receptor antagonist). Finally, acute dependence-like effects following zolpidem administration were assessed with βCCt and 3-PBC (0.1-3.2 mg/kg and 0.32-10 mg/kg, respectively; α1 subunit-containing GABAA receptor antagonists). Chlordiazepoxide, zolpidem, and HZ-166 produced dose- and time-dependent decreases in response rates, whereas flumazenil, βCCT, and 3-PBC were ineffective. After the drug effects waned, flumazenil produced dose-dependent decreases in response rates following administration of 10 mg/kg chlordiazepoxide and 1.0 mg/kg zolpidem, but not following any dose of HZ-166. Further, both βCCT and 3-PBC produced dose-dependent decreases in response rates when administered after 1.0 mg/kg zolpidem. These data raise the possibility that α1 subunit-containing GABAA receptors play a major role in physical dependence-related behaviors following a single injection of a benzodiazepine.

Quantitative disease progression model of α‐1 proteinase inhibitor therapy on computed tomography lung density in patients with α‐1 antitrypsin deficiency

PubMed Central

Rogers, James A.; Vit, Oliver; Bexon, Martin; Sandhaus, Robert A.; Burdon, Jonathan; Chorostowska‐Wynimko, Joanna; Thompson, Philip; Stocks, James; McElvaney, Noel G.; Chapman, Kenneth R.; Edelman, Jonathan M.

2017-01-01

Aims Early‐onset emphysema attributed to α‐1 antitrypsin deficiency (AATD) is frequently overlooked and undertreated. RAPID‐RCT/RAPID‐OLE, the largest clinical trials of purified human α‐1 proteinase inhibitor (A1‐PI; 60 mg kg–1 week–1) therapy completed to date, demonstrated for the first time that A1‐PI is clinically effective in slowing lung tissue loss in AATD. A posthoc pharmacometric analysis was undertaken to further explore dose, exposure and response. Methods A disease progression model was constructed, utilizing observed A1‐PI exposure and lung density decline rates (measured by computed tomography) from RAPID‐RCT/RAPID‐OLE, to predict effects of population variability and higher doses on A1‐PI exposure and clinical response. Dose–exposure and exposure–response relationships were characterized using nonlinear and linear mixed effects models, respectively. The dose–exposure model predicts summary exposures and not individual concentration kinetics; covariates included baseline serum A1‐PI, forced expiratory volume in 1 s and body weight. The exposure–response model relates A1‐PI exposure to lung density decline rate at varying exposure levels. Results A dose of 60 mg kg–1 week–1 achieved trough serum levels >11 μmol l–1 (putative ‘protective threshold’) in ≥98% patients. Dose–exposure–response simulations revealed increasing separation between A1‐PI and placebo in the proportions of patients achieving higher reductions in lung density decline rate; improvements in decline rates ≥0.5 g l–1 year–1 occurred more often in patients receiving A1‐PI: 63 vs. 12%. Conclusion Weight‐based A1‐PI dosing reliably raises serum levels above the 11 μmol l–1 threshold. However, our exposure–response simulations question whether this is the maximal, clinically effective threshold for A1‐PI therapy in AATD. The model suggested higher doses of A1‐PI would yield greater clinical effects. PMID:28662542

The nucleus reticularis gigantocellularis modulates the cardiopulmonary responses to central and peripheral drives related to exercise.

PubMed

Richard, C A; Waldrop, T G; Bauer, R M; Mitchell, J H; Stremel, R W

1989-03-13

It is known that muscle afferents and the hypothalamic locomotor region (HLR) both project to the nucleus reticularis gigantocellularis (NGC) and that the NGC is capable of influencing cardiovascular and respiratory variables. Therefore, the role of NGC in the cardiovascular and respiratory response to exercise-related signals was investigated in anesthetized cats. These signals were generated by stimulation of: (1) spinal ventral roots to induce hindlimb muscle contraction (MC) and (2) the HLR. Bilateral electrolytic lesion of the NGC at the pontomedullary border caused tidal volume, respiratory frequency and heart rate responses to HLR stimulation to be greater than the responses recorded prior to lesioning. Lesioning had no effect on the ventilatory or cardiovascular responses to MC but did decrease phrenic responsiveness; lesion had no effect on any resting values. In this preparation, the pontomedullary NGC acts as an inhibitory influence on tidal volume, breathing frequency and heart rate responses to the central command for exercise. In addition, NGC modulation of ventilation would appear to be selective for certain respiratory muscle groups.

Effects of ploidy level and haplotype on variation of photosynthetic traits: Novel evidence from two Fragaria species

PubMed Central

Gao, Song; Yan, Qiaodi; Chen, Luxi; Song, Yaobin; Fu, Chengxin; Dong, Ming

2017-01-01

To reveal the effects of ploidy level and haplotype on photosynthetic traits, we chose 175 genotypes of wild strawberries belonging to two haplotypes at two types of ploidy levels (diploidy and tetraploidy) and measured photosynthetic traits. Our results revealed that ploidy significantly affected the characteristics of light-response curves, CO2-response curves, and leaf gas exchange parameters, except intercellular CO2 concentration (Ci). Tetraploid species had a lower light saturation point (LSP) and CO2 saturation point (CSP), higher light compensation point (LCP), dark respiration (Rd), and CO2 compensation point (CCP) than diploid species. Furthermore, tetraploid species have lower photosynthetic capacity than diploid species, including net photosynthetic rate (Pn), stomatal conductivity (Gs), and transpiration rate (Tr). In addition, haplotype had a significant effect on LSP, CSP, Tr, and Ci as well as a significant interactive effect between ploidy and haplotype on the maximal photosynethic rate of the light-response curve and Rd. Most of the variance existed within haplotypes among individuals. These results suggest that polyploidization was the main driver for the evolution of photosynthesis with increasing ploidy level (i.e. from diploidy to tetraploidy in Fragaria species), while the origin of a chromosome could also affect the photosynthetic traits and the polyploidization effect on photosynthetic traits. PMID:28644876

Effects of ploidy level and haplotype on variation of photosynthetic traits: Novel evidence from two Fragaria species.

PubMed

Gao, Song; Yan, Qiaodi; Chen, Luxi; Song, Yaobin; Li, Junmin; Fu, Chengxin; Dong, Ming

2017-01-01

To reveal the effects of ploidy level and haplotype on photosynthetic traits, we chose 175 genotypes of wild strawberries belonging to two haplotypes at two types of ploidy levels (diploidy and tetraploidy) and measured photosynthetic traits. Our results revealed that ploidy significantly affected the characteristics of light-response curves, CO2-response curves, and leaf gas exchange parameters, except intercellular CO2 concentration (Ci). Tetraploid species had a lower light saturation point (LSP) and CO2 saturation point (CSP), higher light compensation point (LCP), dark respiration (Rd), and CO2 compensation point (CCP) than diploid species. Furthermore, tetraploid species have lower photosynthetic capacity than diploid species, including net photosynthetic rate (Pn), stomatal conductivity (Gs), and transpiration rate (Tr). In addition, haplotype had a significant effect on LSP, CSP, Tr, and Ci as well as a significant interactive effect between ploidy and haplotype on the maximal photosynethic rate of the light-response curve and Rd. Most of the variance existed within haplotypes among individuals. These results suggest that polyploidization was the main driver for the evolution of photosynthesis with increasing ploidy level (i.e. from diploidy to tetraploidy in Fragaria species), while the origin of a chromosome could also affect the photosynthetic traits and the polyploidization effect on photosynthetic traits.

A Randomized Crossover Trial on Acute Stress-Related Physiological Responses to Mountain Hiking

PubMed Central

Grafetstätter, Carina; Hartl, Arnulf; Kopp, Martin

2017-01-01

Green exercise, defined as physical activity in natural environments, might have positive effects on stress-related physiological measures. Little is known about the acute effects of green exercise bouts lasting longer than 60 min. Therefore, the aim of the present study was to analyze the acute effects of a three-hour green exercise intervention (mountain hiking) on stress-related physiological responses. Using a randomized crossover design, 42 healthy participants were exposed to three different conditions in a field-based experiment: outdoor mountain hiking, indoor treadmill walking, and sedentary control condition (three hours each). At baseline and at follow-up (five minutes after the condition), stress-related physiological responses (salivary cortisol, blood pressure, and heart rate variability) were measured. Salivary cortisol decreased in all conditions, but showed a larger decrease after both mountain hiking and treadmill walking compared to the sedentary control situation (partial η2 = 0.10). No differences were found between mountain hiking and treadmill walking in salivary cortisol. In heart rate variability and blood pressure, changes from baseline to follow-up did not significantly differ between the three conditions. The results indicate that three hours of hiking indoors or outdoors elicits positive effects on salivary cortisol concentration. Environmental effects seem to play a minor role in salivary cortisol, blood pressure, and heart rate variability. PMID:28800067

Improving health promotion through central rating of interventions: the need for Responsive Guidance.

PubMed

Kok, Maarten Olivier; Bal, Roland; Roelofs, Caspar David; Schuit, Albertine Jantine

2017-11-23

In several countries, attempts are made to improve health promotion by centrally rating the effectiveness of health promotion interventions. The Dutch Effectiveness Rating System (ERS) for health promotion interventions is an improvement-oriented approach in which multi-disciplinary expert committees rate available health promotion interventions as 'theoretically sound', 'probably effective' or 'proven effective'. The aim of this study is to explore the functioning of the ERS and the perspective of researchers, policy-makers and practitioners regarding its contribution to improvement. We interviewed 53 selected key informants from research, policy and practice in the Netherlands and observed the assessment of 12 interventions. Between 2008 and 2012, a total of 94 interventions were submitted to the ERS, of which 23 were rejected, 58 were rated as 'theoretically sound', 10 were rated as 'probably effective' and 3 were rated as 'proven effective'. According to participants, the ERS was intended to facilitate both the improvement of available interventions and the improvement of health promotion in practice. While participants expected that describing and rating interventions promoted learning and enhanced the transferability of interventions, they were concerned that the ERS approach was not suitable for guiding intervention development and improving health promotion in practice. The expert committees that assessed the interventions struggled with a lack of norms for the relevance of effects and questions about how effects should be studied and rated. Health promotion practitioners were concerned that the ERS neglected the local adaptation of interventions and did not encourage the improvement of aspects like applicability and costs. Policy-makers and practitioners were worried that the lack of proven effectiveness legitimised cutbacks rather than learning and advancing health promotion. While measuring and centrally rating the effectiveness of interventions can be beneficial, the evidence based-inspired ERS approach is too limited to guide both intervention development and the improvement of health promotion in practice. To better contribute to improving health promotion, a more reflexive and responsive guidance approach is required, namely one which stimulates the improvement of different intervention aspects, provides targeted recommendations to practitioners and provides feedback to those who develop and rate interventions.

Effects of mycoplasmal LAMPs on receptor responses to steroid hormones in mammalian cells.

PubMed

Iyama, K; Zhang, S; Lo, S C

2001-09-01

Many individuals are chronically infected or parasitically colonized with mycoplasmas in their respiratory or urogenital tracts without apparent clinical significance. However, prolonged close interaction between prokaryotic agents and eukaryotic host cells may gradually and significantly alter normal biological or physiological properties of infected hosts. Steroid hormones are associated with rates of cancer formation in human. The purpose of this study is to establish a sensitive reporting system to examine whether mycoplasmal infections affect biological responses to steroid hormones in mammalian cells. We established pMTV-CAT stably transfected cell lines to test the effect of mycoplasmal lipid-associated membrane proteins (LAMPs). Results showed that LAMPs (1 microg/ml) from seven different species of human mycoplasmas-M. penetrans, M. fermentans, M. genitalium, M. salivarium, M. pneumoniae, M. orale, and M. hominis-had an inhibitory effect on androgen receptor (AR) response to 5alpha-dihydrotestosterone (DHT) in the E82 transfectants. The inhibitory effect of mycoplasmal LAMPs appeared to be dose dependent. LAMPs from M. penetrans, M. genitalium, M. salivarium, M. pneumoniae, and M. orale also had an inhibitory effect on glucocorticoid receptor (GR) response to hormone dexamethasone (Dex) in TSU transfectants. In contrast, LAMPs from M. fermentans and M. hominis showed a stimulatory effect on the GR response to Dex in these TSU cells. The results suggest that colonization or chronic infection by mycoplasmas may significantly affect the responses of mammalian host cells to various steroid hormones, potentially affecting rates of cancer formation.

Amifostine reduces side effects and improves complete response rate during radiotherapy: Results of a meta-analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sasse, Andre Deeke; Gontijo de Oliveira Clark, Luciana; Sasse, Emma Chen

Purpose: To evaluate the efficacy of amifostine in diminishing radiotherapy side effects and whether or not it protects the tumor. Methods and Materials: We performed a systematic review and meta-analysis of 14 included randomized controlled trials, comprising 1451 patients, comparing the use of radiotherapy vs. radiotherapy plus amifostine for cancer treatment. Results: The use of amifostine significantly reduced the risk of developing mucositis (odds ratio [OR], 0.37; 95% confidence interval [CI], 0.29-0.48; p < 0.00001), esophagitis (OR, 0.38; CI, 0.26-0.54; p < 0.00001), acute xerostomia (OR, 0.24; CI, 0.15-0.36; p < 0.00001), late xerostomia (OR, 0.33; CI, 0.21-0.51; p

Getting physicians to open the survey: little evidence that an envelope teaser increases response rates.

PubMed

Ziegenfuss, Jeanette Y; Burmeister, Kelly; James, Katherine M; Haas, Lindsey; Tilburt, Jon C; Beebe, Timothy J

2012-03-31

Physician surveys are an important tool to assess attitudes, beliefs and self-reported behaviors of this policy relevant group. In order for a physician to respond to a mailed survey, they must first open the envelope. While there is some evidence that package elements can impact physician response rates, the impact of an envelope teaser is unknown. Here we assess this by testing the impact of adding a brightly colored "$25 incentive" sticker to the outside of an envelope on response rates and nonresponse bias in a survey of physicians. In the second mailing of a survey assessing physicians' moral beliefs and views on controversial health care topics, initial nonrespondents were randomly assigned to receive a survey in an envelope with a colored "$25 incentive" sticker (teaser group) or an envelope without a sticker (control group). Response rates were compared between the teaser and control groups overall and by age, gender, region of the United States, specialty and years in practice. Nonresponse bias was assessed by comparing the demographic composition of the respondents to the nonrespondents in the experimental and control condition. No significant differences in response rates were observed between the experimental and control conditions overall (p = 0.38) or after stratifying by age, gender, region, or practice type. Within the teaser condition, there was some variation in response rate by years since graduation. There was no independent effect of the teaser on response when simultaneously controlling for demographic characteristics (OR = 0.875, p = 0.4112). Neither response rates nor nonresponse bias were impacted by the use of an envelope teaser in a survey of physicians in the United States.

Responsiveness of measures of heartburn improvement in non-erosive reflux disease

PubMed Central

Junghard, Ola; Halling, Katarina

2007-01-01

Background When measuring treatment effect on symptoms, the treatment success variable should be as responsive as possible. The aim of the study was to investigate the responsiveness of various treatment success variables in patients with symptoms of heartburn. Methods A total of 1640 patients with non-erosive reflux disease (NERD) were treated with proton pump inhibitors for 4 weeks. Treatment success variables were based on a symptom questionnaire (Gastrointestinal Symptom Rating Scale) and on investigator-assessed heartburn, measured at baseline and after 4 weeks of treatment. The rates of treatment success were compared with patients' perceived change in symptoms, assessed by the Overall Treatment Effect questionnaire. Results Generally, more stringent treatment success criteria (i.e., those demanding the better response) translated into more responsive treatment success variables. For example, the treatment success variable 'no heartburn' at 4 weeks was more responsive than the variable 'at most mild heartburn' at 4 weeks. Treatment success variables based on change from baseline to 4 weeks were, in general, less responsive than those based on the week 4 assessments only. Conclusion In patients with NERD, responsiveness varied among different treatment success definitions, with more demanding definitions (based on the 4-week assessment) giving better responsiveness. PMID:17562006

Cardiovascular effects of torcetrapib in conscious and pentobarbital-anesthetized dogs.

PubMed

Polakowski, James S; King, Andrew J; Campbell, Thomas J; Nelson, Richard A; Preusser, Lee C; Kempf-Grote, Anita J; Marsh, Kennan C; Gintant, Gary A; Cox, Bryan F; Mittelstadt, Scott W

2009-12-01

Torcetrapib is a cholesteryl ester transfer protein inhibitor with an undesired response of increasing arterial pressure in humans. Pressor responses to torcetrapib have been demonstrated in multiple preclinical species. However, these studies have not related plasma concentrations to observed effects. Our purpose was to 1) characterize the cardiovascular responses of torcetrapib in conscious and anesthetized dogs with measured plasma concentrations; and 2) characterize the hemodynamic effects contributing to hypertension using comprehensively instrumented anesthetized dogs. Torcetrapib was dosed orally (3, 30 mg/kg) and intravenously (0.01, 0.33, 0.1 mg/kg) in conscious and anesthetized dogs, respectively. Mean arterial pressure and heart rate were monitored in both models; additional parameters were measured in anesthetized dogs. Plasma drug concentrations were assessed in both models. In conscious and anesthetized dogs, torcetrapib increased mean arterial pressure 25 and 18 mm Hg and heart rate 35 and 21 beats/min, at 2.94 and 3.99 microg/mL, respectively. In anesthetized dogs, torcetrapib increased pulmonary arterial pressure, both systemic and pulmonary hypertension driven by increases in vascular resistance. The compound increased rate pressure product and myocardial contractility while decreasing time to systolic pressure recovery and ejection time. Thus, torcetrapib-induced pressor responses are mediated by systemic and pulmonary vasoconstriction and are associated with increased myocardial oxygen consumption and positive inotropy.

Additional Evidence for the Accuracy of Biographical Data: Long-Term Retest and Observer Ratings.

ERIC Educational Resources Information Center

Shaffer, Garnett Stokes; And Others

1986-01-01

Investigated accuracy of responses to biodata questionnaire using a test-retest design and informed external observers for verification. Responses from 237 subjects and 200 observers provided evidence that many responses to biodata questionnaire were accurate. Assessed sources of inaccuracy, including social desirability effects, and noted…

The impact of food viscosity on eating rate, subjective appetite, glycemic response and gastric emptying rate.

PubMed

Zhu, Yong; Hsu, Walter H; Hollis, James H

2013-01-01

Understanding the impact of rheological properties of food on postprandial appetite and glycemic response helps to design novel functional products. It has been shown that solid foods have a stronger satiating effect than their liquid equivalent. However, whether a subtle change in viscosity of a semi-solid food would have a similar effect on appetite is unknown. Fifteen healthy males participated in the randomized cross-over study. Each participant consumed a 1690 kJ portion of a standard viscosity (SV) and a high viscosity (HV) semi-solid meal with 1000 mg acetaminophen in two separate sessions. At regular intervals during the three hours following the meal, subjective appetite ratings were measured and blood samples collected. The plasma samples were assayed for insulin, glucose-dependent insulinotropic peptide (GIP), glucose and acetaminophen. After three hours, the participants were provided with an ad libitum pasta meal. Compared with the SV meal, HV was consumed at a slower eating rate (P = 0.020), with postprandial hunger and desire to eat being lower (P = 0.019 and P<0.001 respectively) while fullness was higher (P<0.001). In addition, consuming the HV resulted in lower plasma concentration of GIP (P<0.001), higher plasma concentration of glucose (P<0.001) and delayed gastric emptying as revealed by the acetaminophen absorption test (P<0.001). However, there was no effect of food viscosity on insulin or food intake at the subsequent meal. In conclusion, increasing the viscosity of a semi-solid food modulates glycemic response and suppresses postprandial satiety, although the effect may be short-lived. A slower eating rate and a delayed gastric emptying rate can partly explain for the stronger satiating properties of high viscous semi-solid foods.

The Impact of Food Viscosity on Eating Rate, Subjective Appetite, Glycemic Response and Gastric Emptying Rate

PubMed Central

Zhu, Yong; Hsu, Walter H.; Hollis, James H.

2013-01-01

Understanding the impact of rheological properties of food on postprandial appetite and glycemic response helps to design novel functional products. It has been shown that solid foods have a stronger satiating effect than their liquid equivalent. However, whether a subtle change in viscosity of a semi-solid food would have a similar effect on appetite is unknown. Fifteen healthy males participated in the randomized cross-over study. Each participant consumed a 1690 kJ portion of a standard viscosity (SV) and a high viscosity (HV) semi-solid meal with 1000 mg acetaminophen in two separate sessions. At regular intervals during the three hours following the meal, subjective appetite ratings were measured and blood samples collected. The plasma samples were assayed for insulin, glucose-dependent insulinotropic peptide (GIP), glucose and acetaminophen. After three hours, the participants were provided with an ad libitum pasta meal. Compared with the SV meal, HV was consumed at a slower eating rate (P = 0.020), with postprandial hunger and desire to eat being lower (P = 0.019 and P<0.001 respectively) while fullness was higher (P<0.001). In addition, consuming the HV resulted in lower plasma concentration of GIP (P<0.001), higher plasma concentration of glucose (P<0.001) and delayed gastric emptying as revealed by the acetaminophen absorption test (P<0.001). However, there was no effect of food viscosity on insulin or food intake at the subsequent meal. In conclusion, increasing the viscosity of a semi-solid food modulates glycemic response and suppresses postprandial satiety, although the effect may be short-lived. A slower eating rate and a delayed gastric emptying rate can partly explain for the stronger satiating properties of high viscous semi-solid foods. PMID:23818981

The effects of smoking and abstinence on experience of happiness and sadness in response to positively valenced, negatively valenced, and neutral film clips.

PubMed

Dawkins, Lynne; Acaster, Sarah; Powell, Jane H

2007-02-01

Incentive motivation theories of addiction suggest that behavioural concomitants of compromised mesocorticolimbic reward activity during abstinence might include decreased affective reactions to natural reinforcers. This study tested implications for hedonic reactions in abstinent smokers. It was hypothesised that positively valenced (pleasurable) film clips would elicit lower ratings of happiness in abstinent than satiated smokers. Twenty-nine smokers, randomly assigned to either an 'abstinent' or a 'satiated' condition, and 15 non-smokers took part in a single session in which they rated (i) signs and symptoms of nicotine withdrawal and (ii) affective responses to positively valenced, negatively valenced, and neutral film clips. Compared with satiated smokers, abstinent smokers rated positive clips as eliciting significantly lower levels of happiness, and this was independent of self-reported nicotine withdrawal symptoms; the scores of non-smokers fell between those of abstinent and satiated smokers, more closely approximating those of the latter. By contrast, sadness ratings in response to negative clips were not affected by smoking status, indicating that the effect on happiness was not simply due to general emotional blunting. These results suggest that, for regular smokers, stimuli that are motivationally salient for the general population may elicit reduced positive affective responses during periods of abstinence.

Cyclophosphamide, thalidomide, and dexamethasone (CTD) as initial therapy for patients with multiple myeloma unsuitable for autologous transplantation

PubMed Central

Davies, Faith E.; Gregory, Walter M.; Russell, Nigel H.; Bell, Sue E.; Szubert, Alexander J.; Coy, Nuria Navarro; Cook, Gordon; Feyler, Sylvia; Byrne, Jenny L.; Roddie, Huw; Rudin, Claudius; Drayson, Mark T.; Owen, Roger G.; Ross, Fiona M.; Jackson, Graham H.; Child, J. Anthony

2011-01-01

As part of the randomized MRC Myeloma IX trial, we compared an attenuated regimen of cyclophosphamide, thalidomide, and dexamethasone (CTDa; n = 426) with melphalan and prednisolone (MP; n = 423) in patients with newly diagnosed multiple myeloma ineligible for autologous stem-cell transplantation. The primary endpoints were overall response rate, progression-free survival, and overall survival (OS). The overall response rate was significantly higher with CTDa than MP (63.8% vs 32.6%; P < .0001), primarily because of increases in the rate of complete responses (13.1% vs 2.4%) and very good partial responses (16.9% vs 1.7%). Progression-free survival and OS were similar between groups. In this population, OS correlated with the depth of response (P < .0001) and favorable interphase fluorescence in situ hybridization profile (P < .001). CTDa was associated with higher rates of thromboembolic events, constipation, infection, and neuropathy than MP. In elderly patients with newly diagnosed multiple myeloma (median age, 73 years), CTDa produced higher response rates than MP but was not associated with improved survival outcomes. We highlight the importance of cytogenetic profiling at diagnosis and effective management of adverse events. This trial was registered at International Standard Randomized Controlled Trials Number as #68454111. PMID:21652683

SMS text pre-notification and delivery of reminder e-mails to increase response rates to postal questionnaires in the SUSPEND trial: a factorial design, randomised controlled trial.

PubMed

Starr, Kathryn; McPherson, Gladys; Forrest, Mark; Cotton, Seonaidh C

2015-07-08

Patient-reported outcomes are vital in informing randomised controlled trials (RCTs) and health-care interventions and policies from the patient's perspective. However, participant non-response may introduce bias and can affect the generalisability of the trial. This study evaluates two interventions aimed at increasing response rates to postal questionnaires within a large, UK-wide RCT: pre-notification via short messenger service (SMS) text prior to sending the initial mailing of trial questionnaires versus no pre-notification; for non-responders to the initial mailing of the questionnaires, an e-mail reminder (containing a hyperlink to complete the questionnaire online) versus a postal reminder. This study is a 2 × 2 partial factorial design RCT nested within an RCT of medical expulsive therapy for ureteric stone disease. Participants who supplied a mobile telephone number were randomly assigned to receive an SMS text pre-notification of questionnaire delivery or no pre-notification. Those who supplied an e-mail address were randomly assigned to receive a questionnaire reminder by e-mail or post. Participants could be randomly assigned to the pre-notification comparison or the reminder comparison or both. The primary outcome measure was response rate at each questionnaire time point. Four hundred eighteen participants were randomly assigned to the SMS pre-notification comparison (80% were male, and the mean age was 41 years with a standard deviation (SD) of 11.1). The intervention had no effect on response rate at either questionnaire time point. In subgroup analyses, SMS pre-notification increased response rates in women but only at the first questionnaire time point. One hundred nineteen participants were randomly assigned to the reminder comparison (80% were male, and the mean age was 42 years with an SD of 12.1). There was no difference in response rate in those who received an e-mail reminder compared with those who received a postal reminder. SMS text pre-notification of questionnaire delivery and email delivery of questionnaire reminders did not improve response rates. There was some evidence to suggest that SMS text pre-notification may be effective in women, and further studies to investigate this may be warranted. E-mail reminders for participants to return their postal questionnaire could be advantageous given that response rates were similar following either type of reminder and the low cost of delivering an e-mail compared with a postal reminder. This is a substudy of the SUSPEND trial (ISCTRN69423238) (18 Nov. 2010).

Effects of a Financial Incentive on Health Researchers’ Response to an Online Survey: a Randomized Controlled Trial

PubMed Central

Petticrew, Mark; Calnan, Mike; Nazareth, Irwin

2010-01-01

Background Nonresponse to questionnaires can affect the validity of surveys and introduce bias. Offering financial incentives can increase response rates to postal questionnaires, but the effect of financial incentives on response rates to online surveys is less clear. Objective As part of a survey, we aimed to test whether knowledge of a financial incentive would increase the response rate to an online questionnaire. Methods A randomized controlled trial of 485 UK-based principal investigators of publicly funded health services and population health research. Participants were contacted by email and invited to complete an online questionnaire via an embedded URL. Participants were randomly allocated to groups with either “knowledge of” or “no knowledge of” a financial incentive (£10 Amazon gift voucher) to be provided on completion of the survey. At the end of the study, gift vouchers were given to all participants who completed the questionnaire regardless of initial randomization status. Four reminder emails (sent from the same email address as the initial invitation) were sent out to nonrespondents at one, two, three, and four weeks; a fifth postal reminder was also undertaken. The primary outcome measure for the trial was the response rate one week after the second reminder. Response rate was also measured at the end of weeks one, two, three, four, and five, and after a postal reminder was sent. Results In total, 243 (50%) questionnaires were returned (232 completed, 11 in which participation was declined). One week after the second reminder, the response rate in the “knowledge” group was 27% (66/244) versus 20% (49/241) in the “no knowledge” group (χ21 = 3.0, P = .08). The odds ratio for responding among those with knowledge of an incentive was 1.45 (95% confidence interval [CI] 0.95 - 2.21). At the third reminder, participants in the “no knowledge” group were informed about the incentive, ending the randomized element of the study. However we continued to follow up all participants, and from reminder three onwards, no significant differences were observed in the response rates of the two groups. Conclusions Knowledge of a financial incentive did not significantly increase the response rate to an online questionnaire. Future surveys should consider including a randomized element to further test the utility of offering incentives of other types and amounts to participate in online questionnaires. Trial Registration ISRCTN59912797; http://www.controlled-trials.com/ISRCTN59912797 (Archived by WebCite at http://www.webcitation.org/5iPPLbT7s) PMID:20457556

Effects of a preceptorship programme on turnover rate, cost, quality and professional development.

PubMed

Lee, Tso-Ying; Tzeng, Wen-Chii; Lin, Chia-Huei; Yeh, Mei-Ling

2009-04-01

The purpose of the present study was to design a preceptorship programme and to evaluate its effects on turnover rate, turnover cost, quality of care and professional development. A high turnover rate of nurses is a common global problem. How to improve nurses' willingness to stay in their jobs and reduce the high turnover rate has become a focus. Well-designed preceptorship programmes could possibly decrease turnover rates and improve professional development. A quasi-experimental research design was used. First, a preceptorship programme was designed to establish the role and responsibilities of preceptors in instructing new nurses. Second, a quasi-experimental design was used to evaluate the preceptorship programme. Data on new nurses' turnover rate, turnover cost, quality of nursing care, satisfaction of preceptor's teaching and preceptor's perception were measured. After conducting the preceptorship programme, the turnover rate was 46.5% less than the previous year. The turnover cost was decreased by US$186,102. Additionally, medication error rates made by new nurses dropped from 50-0% and incident rates of adverse events and falls decreased. All new nurses were satisfied with preceptor guidance. The preceptorship programme effectively lowered the turnover rate of new nurses, reduced turnover costs and enhanced the quality of nursing care, especially by reducing medication error incidents. Positive feedback about the programme was received from new nurses. Study findings may offer healthcare administrators another option for retaining new nurses, controlling costs, improving quality and fostering professional development. In addition, incentives and effective support from the organisation must be considered when preceptors perform preceptorship responsibilities.

An Analysis of "Reinforcement" History Effects

ERIC Educational Resources Information Center

Okouchi, Hiroto; Lattal, Kennon A.

2006-01-01

Four pigeons were exposed to two tandem variable-interval differential-reinforcement-of-low-rate schedules under different stimulus conditions. The values of the tandem schedules were adjusted so that reinforcement rates in one stimulus condition were higher than those in the other, even though response rates in the two conditions were nearly…

Children's Heart Rate Reactivity Responses to Three School Tasks.

ERIC Educational Resources Information Center

Sharpley, Christopher F.; And Others

1989-01-01

Investigated effects of 3 routine classroom arithmetic and reading tasks upon the heart rate reactivity of 30 fifth grade children. Results indicated that some children showed large increases in heart rates during the three tasks, and that these children should be considered at risk for coronary heart disease. (Author/TE)

Concurrent Reinforcement Schedules for Problem Behavior and Appropriate Behavior: Experimental Applications of the Matching Law

ERIC Educational Resources Information Center

Borrero, Carrie S. W.; Vollmer, Timothy R.; Borrero, John C.; Bourret, Jason C.; Sloman, Kimberly N.; Samaha, Andrew L.; Dallery, Jesse

2010-01-01

This study evaluated how children who exhibited functionally equivalent problem and appropriate behavior allocate responding to experimentally arranged reinforcer rates. Relative reinforcer rates were arranged on concurrent variable-interval schedules and effects on relative response rates were interpreted using the generalized matching equation.…

Contact and nutrient caregiving effects on newborn infant pain responses.

PubMed

Gormally, S; Barr, R G; Wertheim, L; Alkawaf, R; Calinoiu, N; Young, S N

2001-01-01

To understand how the 'caregiving context' could affect responses to procedural pain, the authors sought to determine whether (1) the combined effects of sweet taste and holding (caregiving contact) were greater than the effects of either alone, (2) any combined effects were additive or interactive, and (3) the interventions had similar effects on behavioral (crying and facial activity) and physiological (heart rate, vagal tone) responses to the heel-stick procedure in newborn infants in a randomized two-factorial intervention trial. Eighty-five normally developing newborn infants were studied with a mean gestational age of 39.4 weeks on the 2nd or 3rd day of life. Infants were randomized in blocks of eight to receive (1) no holding and water taste (control participants), (2) no holding and sucrose taste (sucrose group), (3) holding and water taste (holding group), or (4) holding and sucrose taste (holding and sucrose group). Crying was reduced significantly by taste and holding, and the interventions combined additively. Facial activity was only significantly reduced by holding. For physiological measures, the interventions interacted with each other and preintervention levels to reduce heart rate and lower vagal tone more during the procedure in infants in whom heart rate and vagal tone were higher before intervention. Consequently, sweet taste and holding interventions combined in complex ways when acting on different behavioral and physiological response systems to modify stressful pain experiences. The results suggest that providing a caregiving context when painful procedures are performed may be a simple and practical method of reducing pain experience in infants, and that no one measure captures these effects.

Verbal collision avoidance messages during simulated driving: perceived urgency, alerting effectiveness and annoyance.

PubMed

Baldwin, Carryl L

2011-04-01

Matching the perceived urgency of an alert with the relative hazard level of the situation is critical for effective alarm response. Two experiments describe the impact of acoustic and semantic parameters on ratings of perceived urgency, annoyance and alerting effectiveness and on alarm response speed. Within a simulated driving context, participants rated and responded to collision avoidance system (CAS) messages spoken by a female or male voice (experiments 1 and 2, respectively). Results indicated greater perceived urgency and faster alarm response times as intensity increased from -2 dB signal to noise (S/N) ratio to +10 dB S/N, although annoyance ratings increased as well. CAS semantic content interacted with alarm intensity, indicating that at lower intensity levels participants paid more attention to the semantic content. Results indicate that both acoustic and semantic parameters independently and interactively impact CAS alert perceptions in divided attention conditions and this work can inform auditory alarm design for effective hazard matching. Matching the perceived urgency of an alert with the relative hazard level of the situation is critical for effective alarm response. Here, both acoustic and semantic parameters independently and interactively impacted CAS alert perceptions in divided attention conditions. This work can inform auditory alarm design for effective hazard matching. STATEMENT OF RELEVANCE: Results indicate that both acoustic parameters and semantic content can be used to design collision warnings with a range of urgency levels. Further, these results indicate that verbal warnings tailored to a specific hazard situation may improve hazard-matching capabilities without substantial trade-offs in perceived annoyance.

Cardiovascular responses to noise: Effects of self-estimated sensitivity to noise, sex, and time of the day

NASA Astrophysics Data System (ADS)

di Nisi, J.; Muzet, A.; Weber, L. D.

1987-04-01

Eighty subjects of both sexes were selected according to their self-estimated high or low sensitivity to noise. Noise exposure took place during a mental task ("sound" condition) or during a video film illustrating the noises ("sound and video" condition). The experiments were conducted between 0900 and 1100 hours or between 1500 and 1700 hours. Heart rate response and finger pulse response amplitudes were averaged separately for "sound" and "sound and video" conditions. In the "sound" condition, the average amplitude of the heart rate response differed significantly between noise-sensitivity groups: the low sensitivity group showed a lower average amplitude of heart rate response than the high sensitivity group. A significant interaction between sex and time of the day (morning or afternoon) was observed in both "sound" and "sound and video" conditions. In the "sound" condition, the percentage of noises inducing a finger pulse response appeared higher in female than in male subjects.

Effects of partial reinforcement and time between reinforced trials on terminal response rate in pigeon autoshaping.

PubMed

Gottlieb, Daniel A

2006-03-01

Partial reinforcement often leads to asymptotically higher rates of responding and number of trials with a response than does continuous reinforcement in pigeon autoshaping. However, comparisons typically involve a partial reinforcement schedule that differs from the continuous reinforcement schedule in both time between reinforced trials and probability of reinforcement. Two experiments examined the relative contributions of these two manipulations to asymptotic response rate. Results suggest that the greater responding previously seen with partial reinforcement is primarily due to differential probability of reinforcement and not differential time between reinforced trials. Further, once established, differences in responding are resistant to a change in stimulus and contingency. Secondary response theories of autoshaped responding (theories that posit additional response-augmenting or response-attenuating mechanisms specific to partial or continuous reinforcement) cannot fully accommodate the current body of data. It is suggested that researchers who study pigeon autoshaping train animals on a common task prior to training them under different conditions.

The role of nicotinic receptor beta-2 subunits in nicotine discrimination and conditioned taste aversion.

PubMed

Shoaib, M; Gommans, J; Morley, A; Stolerman, I P; Grailhe, R; Changeux, J-P

2002-03-01

The subtypes of nicotinic receptors at which the behavioural effects of nicotine originate are not fully understood. These experiments use mice lacking the beta2 subunit of nicotinic receptors to investigate its role in nicotine discrimination and conditioned taste aversion (CTA). Wild-type and mutant mice were trained either in a two-lever nicotine discrimination procedure using a tandem schedule of food reinforcement, or in a counterbalanced two-flavour CTA procedure. Rates of lever-pressing of wild-type and mutant mice did not differ. Wild-type mice acquired discrimination of nicotine (0.4 or 0.8 mg/kg) rapidly and exhibited steep dose-response curves. Mutant mice failed to acquire these nicotine discriminations and exhibited flat dose-response curves. Both wild-type and mutant mice acquired discrimination of nicotine (1.6 mg/kg) although discrimination performance was weak in the mutants. Nicotine initially reduced response rates in wild-type and mutant mice, and tolerance developed to this effect in each genotype. Both genotypes acquired discrimination of morphine (3 mg/kg) with similar degrees of accuracy, and dose-response curves for morphine discrimination in the two genotypes were indistinguishable. Nicotine produced dose-related CTA in both genotypes, but the magnitude of the effect was less in the mutants than in the wild-type controls. It is concluded that nicotinic receptors containing the beta2 subunit play a major role in the discriminative stimulus and taste aversion effects of nicotine that may reflect psychological aspects of tobacco dependence. Such receptors appear to have a less crucial role in the response-rate, reducing effects of nicotine and in nicotine tolerance.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jeong, J; Deasy, J O

Purpose: Concurrent chemo-radiation therapy (CCRT) has become a more common cancer treatment option with a better tumor control rate for several tumor sites, including head and neck and lung cancer. In this work, possible optimal chemotherapy schedules were investigated by implementing chemotherapy cell-kill into a tumor response model of RT. Methods: The chemotherapy effect has been added into a published model (Jeong et al., PMB (2013) 58:4897), in which the tumor response to RT can be simulated with the effects of hypoxia and proliferation. Based on the two-compartment pharmacokinetic model, the temporal concentration of chemotherapy agent was estimated. Log cell-killmore » was assumed and the cell-kill constant was estimated from the observed increase in local control due to concurrent chemotherapy. For a simplified two cycle CCRT regime, several different starting times and intervals were simulated with conventional RT regime (2Gy/fx, 5fx/wk). The effectiveness of CCRT was evaluated in terms of reduction in radiation dose required for 50% of control to find the optimal chemotherapy schedule. Results: Assuming the typical slope of dose response curve (γ50=2), the observed 10% increase in local control rate was evaluated to be equivalent to an extra RT dose of about 4 Gy, from which the cell-kill rate of chemotherapy was derived to be about 0.35. Best response was obtained when chemotherapy was started at about 3 weeks after RT began. As the interval between two cycles decreases, the efficacy of chemotherapy increases with broader range of optimal starting times. Conclusion: The effect of chemotherapy has been implemented into the resource-conservation tumor response model to investigate CCRT. The results suggest that the concurrent chemotherapy might be more effective when delayed for about 3 weeks, due to lower tumor burden and a larger fraction of proliferating cells after reoxygenation.« less

Discriminating the Drivers of Edge Effects on Nest Predation: Forest Edges Reduce Capture Rates of Ship Rats (Rattus rattus), a Globally Invasive Nest Predator, by Altering Vegetation Structure

PubMed Central

Ruffell, Jay; Didham, Raphael K.; Barrett, Paul; Gorman, Nic; Pike, Rhonda; Hickey-Elliott, Andrée; Sievwright, Karin; Armstrong, Doug P.

2014-01-01

Forest edges can strongly affect avian nest success by altering nest predation rates, but this relationship is inconsistent and context dependent. There is a need for researchers to improve the predictability of edge effects on nest predation rates by examining the mechanisms driving their occurrence and variability. In this study, we examined how the capture rates of ship rats, an invasive nest predator responsible for avian declines globally, varied with distance from the forest edge within forest fragments in a pastoral landscape in New Zealand. We hypothesised that forest edges would affect capture rates by altering vegetation structure within fragments, and that the strength of edge effects would depend on whether fragments were grazed by livestock. We measured vegetation structure and rat capture rates at 488 locations ranging from 0–212 m from the forest edge in 15 forest fragments, seven of which were grazed. Contrary to the vast majority of previous studies of edge effects on nest predation, ship rat capture rates increased with increasing distance from the forest edge. For grazed fragments, capture rates were estimated to be 78% lower at the forest edge than 118 m into the forest interior (the farthest distance for grazed fragments). This relationship was similar for ungrazed fragments, with capture rates estimated to be 51% lower at the forest edge than 118 m into the forest interior. A subsequent path analysis suggested that these ‘reverse’ edge effects were largely or entirely mediated by changes in vegetation structure, implying that edge effects on ship rats can be predicted from the response of vegetation structure to forest edges. We suggest the occurrence, strength, and direction of edge effects on nest predation rates may depend on edge-driven changes in local habitat when the dominant predator is primarily restricted to forest patches. PMID:25412340

Discriminating the drivers of edge effects on nest predation: forest edges reduce capture rates of ship rats (Rattus rattus), a globally invasive nest predator, by altering vegetation structure.

PubMed

Ruffell, Jay; Didham, Raphael K; Barrett, Paul; Gorman, Nic; Pike, Rhonda; Hickey-Elliott, Andrée; Sievwright, Karin; Armstrong, Doug P

2014-01-01

Forest edges can strongly affect avian nest success by altering nest predation rates, but this relationship is inconsistent and context dependent. There is a need for researchers to improve the predictability of edge effects on nest predation rates by examining the mechanisms driving their occurrence and variability. In this study, we examined how the capture rates of ship rats, an invasive nest predator responsible for avian declines globally, varied with distance from the forest edge within forest fragments in a pastoral landscape in New Zealand. We hypothesised that forest edges would affect capture rates by altering vegetation structure within fragments, and that the strength of edge effects would depend on whether fragments were grazed by livestock. We measured vegetation structure and rat capture rates at 488 locations ranging from 0-212 m from the forest edge in 15 forest fragments, seven of which were grazed. Contrary to the vast majority of previous studies of edge effects on nest predation, ship rat capture rates increased with increasing distance from the forest edge. For grazed fragments, capture rates were estimated to be 78% lower at the forest edge than 118 m into the forest interior (the farthest distance for grazed fragments). This relationship was similar for ungrazed fragments, with capture rates estimated to be 51% lower at the forest edge than 118 m into the forest interior. A subsequent path analysis suggested that these 'reverse' edge effects were largely or entirely mediated by changes in vegetation structure, implying that edge effects on ship rats can be predicted from the response of vegetation structure to forest edges. We suggest the occurrence, strength, and direction of edge effects on nest predation rates may depend on edge-driven changes in local habitat when the dominant predator is primarily restricted to forest patches.

The Effect of the Laboratory Specimen on Fatigue Crack Growth Rate

NASA Technical Reports Server (NTRS)

Forth, S. C.; Johnston, W. M.; Seshadri, B. R.

2006-01-01

Over the past thirty years, laboratory experiments have been devised to develop fatigue crack growth rate data that is representative of the material response. The crack growth rate data generated in the laboratory is then used to predict the safe operating envelope of a structure. The ability to interrelate laboratory data and structural response is called similitude. In essence, a nondimensional term, called the stress intensity factor, was developed that includes the applied stresses, crack size and geometric configuration. The stress intensity factor is then directly related to the rate at which cracks propagate in a material, resulting in the material property of fatigue crack growth response. Standardized specimen configurations and experimental procedures have been developed for laboratory testing to generate crack growth rate data that supports similitude of the stress intensity factor solution. In this paper, the authors present laboratory fatigue crack growth rate test data and finite element analyses that show similitude between standard specimen configurations tested using the constant stress ratio test method is unobtainable.

The role of increased exposure to transfer-of-stimulus-control procedures on the acquisition of intraverbal behavior.

PubMed

Coon, Jared T; Miguel, Caio F

2012-01-01

Studies that have compared the effectiveness of differing prompt types to teach intraverbal responses have yielded mixed results, suggesting that individuals' reinforcement histories with prompt types may influence which prompt will be most effective. The purpose of this study was to test whether programmed increases in exposure to specific prompt types would produce concomitant increases in the acquisition rate of intraverbal responding. We compared acquisition rates among 4 typically developing preschool-aged children when taught via either echoic or tact prompts following exposure training with 1 prompt type. For all participants, the prompt method most recently used to teach intraverbal responses required fewer trials to teach new intraverbal responses compared to a prompt method that had not been used recently. The results are discussed in terms of the effects of reinforcement history on the acquisition of verbal behavior.

THE ROLE OF INCREASED EXPOSURE TO TRANSFER-OF-STIMULUS-CONTROL PROCEDURES ON THE ACQUISITION OF INTRAVERBAL BEHAVIOR

PubMed Central

Coon, Jared T.; Miguel, Caio F.

2012-01-01

Studies that have compared the effectiveness of differing prompt types to teach intraverbal responses have yielded mixed results, suggesting that individuals' reinforcement histories with prompt types may influence which prompt will be most effective. The purpose of this study was to test whether programmed increases in exposure to specific prompt types would produce concomitant increases in the acquisition rate of intraverbal responding. We compared acquisition rates among 4 typically developing preschool-aged children when taught via either echoic or tact prompts following exposure training with 1 prompt type. For all participants, the prompt method most recently used to teach intraverbal responses required fewer trials to teach new intraverbal responses compared to a prompt method that had not been used recently. The results are discussed in terms of the effects of reinforcement history on the acquisition of verbal behavior. PMID:23322924

The effect of timing of incentive payments on response rates for cohort study telephone interviews in primary care setting with cost-minimization analysis, a randomized controlled trial.

PubMed

Chin, Weng-Yee; Choi, Edmond P H; Lam, Cindy L K

2015-10-06

The effect of timing of incentive payments on the response rate of telephone surveys is unknown. This study examined whether up-front or delayed incentive payments were associated with higher response rates for participation in a telephone interview administered longitudinal cohort study amongst primary care patients with lower urinary tract symptoms, and to compare the costs between the two timing methods. This study was conducted as part of a naturalistic observation study on the health-related quality of life and health outcomes of Chinese primary care patients with lower urinary tract symptoms. The incentive payment was in the form of a supermarket gift voucher to the value of HD$50 (US$6.50) and could be used in lieu of cash at a major supermarket chain.720 subjects with lower urinary tract symptoms were randomly assigned into two groups. One group was offered an incentive of supermarket cash voucher at time of recruitment ('up-front' payment). The other group was told that the voucher would be sent to them after the complete of their 1-year follow-up telephone interview ('delayed' payment). Primary outcomes were the baseline and 1-year follow-up telephone survey response rates. There was no statistical difference in response rates at baseline (p-value = 0.938) or at the 1-year follow-up (p-value = 0.751) between groups. Cost per completed subject interviews for the up-front payment method was USD16.64, whilst cost for the delayed payment was USD 13.85. It appears the timing of incentive payments does not affect response rates for telephone interview surveys conducted on primary care patients in Hong Kong at baseline or at 1-year follow-up. Delayed incentive payments can reduce the overall cost per successful case. ClinicalTrials.gov Identifier: NCT02307929 Registered 28 August 2013.

Remote Collection of Patient-Reported Outcomes Following Outpatient Hand Surgery: A Randomized Trial of Telephone, Mail, and E-Mail.

PubMed

Schwartzenberger, Justin; Presson, Angela; Lyle, Adam; O'Farrell, Andrew; Tyser, Andrew R

2017-09-01

Obtaining remote patient-reported outcomes (PRO) is limited by low patient response rates and resource-intensive collection methods. We hypothesized that an e-mail-delivered Web-based data collection tool would outperform the traditional methods of telephone and standard mail for collecting long-term Boston Carpal Tunnel Questionnaire (BCTQ) scores at a minimum of 1 year following carpal tunnel release (CTR). We conducted a randomized trial of 969 patients who underwent CTR at a tertiary medical center within the past 5 years. Participants were randomized to the PRO collection methods of mail, telephone, and e-mail. The primary outcome was survey response rate at 1 year after surgery. Secondary analyses included data completeness and the effect of time from surgery, mode effects, and patient modality preference. At 1 year from surgery, the response rates were 64% for telephone and 42% for both mail and e-mail. Ninety-nine percent of telephone surveys were complete compared with 88% and 83% for mail and e-mail, respectively. There was no significant difference in the overall response rate at 1 or 5 years after surgery, nor in the BCTQ score between the modalities. A higher response rate and increased survey completeness was achieved by telephone contact methods compared with standard mailings or Web-based methods for PRO collection after CTR 1 to 5 years after surgery. A Web-based method demonstrated response rates equivalent to those of standard mail, was the most preferred modality, and offered logistical advantages such as automation and immediate integration with outcome databases. Obtaining PRO routinely after treatment may increase in importance. A Web-based interface may assist clinicians in decreasing the resource utilization typically associated with more traditional methods used to obtain outcome data. Copyright © 2017 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

[Optimization of Polysaccharide Extraction from Spirodela polyrrhiza by Plackett-Burman Design Combined with Box-Behnken Response Surface Methodology].

PubMed

Jiang, Zheng; Wang, Hong; Wu, Qi-nan

2015-06-01

To optimize the processing of polysaccharide extraction from Spirodela polyrrhiza. Five factors related to extraction rate of polysaccharide were optimized by the Plackett-Burman design. Based on this study, three factors, including alcohol volume fraction, extraction temperature and ratio of material to liquid, were regarded as investigation factors by Box-Behnken response surface methodology. The effect order of three factors on the extraction rate of polysaccharide from Spirodela polyrrhiza were as follows: extraction temperature, alcohol volume fraction,ratio of material to liquid. According to Box-Behnken response, the best extraction conditions were: alcohol volume fraction of 81%, ratio of material to liquid of 1:42, extraction temperature of 100 degrees C, extraction time of 60 min for four times. Plackett-Burman design and Box-Behnken response surface methodology used to optimize the extraction process for the polysaccharide in this study is effective and stable.

Changes During Recovery from Sodium Deficiency in Atriplex

PubMed Central

Brownell, P. F.; Jackman, Margaret E.

1966-01-01

Although the concentration of sodium in leaves of Atriplex plants increased rapidly after receiving sodium, no growth response was detectable for about 6 days. It was found that respiration rate increased to its maximum within 3 days. Chlorophyll content also increased from an early stage, whereas the concentrations of sugars and starch did not increase, and ratios of soluble to total nitrogen did not decrease until later. The respiratory response appears to be specific to sodium as different salts of sodium caused similar responses, and no other univalent cation substituted for sodium. In addition, both growth response and respiration rate tended towards their maxima with the same concentration of applied sodium. The rate of anaerobic CO2 production increased when sodium was fed to leaves, suggesting that the effect of sodium is in the glycolytic sequence. PMID:16656296

Low-Dose Radiation Therapy (2 Gy × 2) in the Treatment of Orbital Lymphoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fasola, Carolina E.; Jones, Jennifer C.; Huang, Derek D.

2013-08-01

Purpose: Low-dose radiation has become increasingly used in the management of indolent non-Hodgkin lymphoma (NHL), but has not been studied specifically for cases of ocular adnexal involvement. The objective of this study is to investigate the effectiveness of low-dose radiation in the treatment of NHL of the ocular adnexa. Methods and Materials: We reviewed the records of 20 NHL patients with 27 sites of ocular adnexal involvement treated with low-dose radiation consisting of 2 successive fractions of 2 Gy at our institution between 2005 and 2011. The primary endpoint of this study is freedom from local relapse (FFLR). Results: Atmore » a median follow-up time of 26 months (range 7-92), the overall response rate for the 27 treated sites was 96%, with a complete response (CR) rate of 85% (n=23) and a partial response rate of 11% (n=3). Among all treated sites with CR, the 2-year FFLR was 100%, with no in-treatment field relapses. The 2-year freedom from regional relapse rate was 96% with 1 case of relapse within the ipsilateral orbit (outside of the treatment field). This patient underwent additional treatment with low-dose radiation of 4 Gy to the area of relapse achieving a CR and no evidence of disease at an additional 42 months of follow-up. Orbital radiation was well tolerated with only mild acute side effects (dry eye, conjunctivitis, transient periorbital edema) in 30% of treated sites without any reports of long-term toxicity. Conclusions: Low-dose radiation with 2 Gy × 2 is effective and well tolerated in the treatment of indolent NHL of the ocular adnexa with high response rates and durable local control with the option of reirradiation in the case of locoregional relapse.« less

A Comparative Study of Liquid Nitrogen Cryotherapy as Monotherapy versus in Combination with Podophyllin in the Treatment of Condyloma Acuminata.

PubMed

Sharma, Nidhi; Sharma, Sanjeev; Singhal, Chetna

2017-03-01

Condyloma Acuminata (CA) is a common viral sexually transmitted disease. Although various treatment modalities are available for treating CA, but none of them can achieve 100% response rate. In a search for better response rate and less recurrence rate, the combination of cytotoxic agent Podophyllin with ablative liquid nitrogen cryotherapy was evaluated over cryotherapy alone. To evaluate the synergistic effect of Podophyllin as a chemotherapeutic adjunct to an ablative therapy of liquid nitrogen cryotherapy versus liquid nitrogen cryotherapy alone in the treatment of CA. Sixty patients with multiple CA were randomly assigned to two groups in the study. Thirty patients in group A received double freeze thaw cycle of 25 seconds of liquid nitrogen cryotherapy. Thirty patients in Group B were subjected to liquid nitrogen cryotherapy in a similar manner followed by application of not more than 0.5 ml of 25% Podophyllin solution. All patients were followed up at 1, 4, 8, 12 and 24 weeks after the treatment to monitor the response to therapy and evaluation for any recurrence. When the number of unresponsive lesions were more than 30% of original lesions at 4 weeks follow-up, then the whole procedure was repeated again. The complete response rate and the recurrence rate in the Group B in our study were comparable to Group A as the difference was statistically insignificant. But the differentiating point was that the similar results were obtained in Group B with an average1.2 sessions per patient in comparison to an average of 1.67 sessions per patient in Group A. Cryotherapy represents a simple, safe and effective regimen for the treatment of multiple CA which in combination with Podophyllin is even more effective as a single session procedure; thereby shortening the treatment regimen.

The effect of low dose rate on metabolomic response to radiation in mice

PubMed Central

Goudarzi, Maryam; Mak, Tytus D.; Chen, Congju; Smilenov, Lubomir B.; Brenner, David J.

2014-01-01

Metabolomics has been shown to have utility in assessing responses to exposure by ionizing radiation (IR) in easily accessible biofluids such as urine. Most studies to date from our laboratory and others have employed γ-irradiation at relatively high dose rates (HDR), but many environmental exposure scenarios will probably be at relatively low dose rates (LDR). There are well-documented differences in the biologic responses to LDR compared to HDR, so an important question is to assess LDR effects at the metabolomics level. Our study took advantage of a modern mass spectrometry approach in exploring the effects of dose rate on the urinary excretion levels of metabolites 2 days after IR in mice. A wide variety of statistical tools were employed to further focus on metabolites, which showed responses to LDR IR exposure (0.00309 Gy/min) distinguishable from those of HDR. From a total of 709 detected spectral features, more than 100 were determined to be statistically significant when comparing urine from mice irradiated with 1.1 or 4.45 Gy to that of sham-irradiated mice 2 days post-exposure. The results of this study show that LDR and HDR exposures perturb many of the same pathways such as TCA cycle and fatty acid metabolism, which also have been implicated in our previous IR studies. However, it is important to note that dose rate did affect the levels of particular metabolites. Differences in urinary excretion levels of such metabolites could potentially be used to assess an individual's exposure in a radiobiological event and thus would have utility for both triage and injury assessment. PMID:25047638

Equilibrium muscle cross-bridge behavior. Theoretical considerations.

PubMed Central

Schoenberg, M

1985-01-01

We have developed a model for the equilibrium attachment and detachment of myosin cross-bridges to actin that takes into account the possibility that a given cross-bridge can bind to one of a number of actin monomers, as seems likely, rather than to a site on only a single actin monomer, as is often assumed. The behavior of this multiple site model in response to constant velocity, as well as instantaneous stretches, was studied and the influence of system parameters on the force response explored. It was found that in the multiple site model the detachment rate constant has considerably greater influence on the mechanical response than the attachment rate constant. It is shown that one can obtain information about the detachment rate constants either by examining the relationship between the apparent stiffness and duration of stretch for constant velocity stretches or by examining the force-decay rate constants following an instantaneous stretch. The main effect of the attachment rate constant is to scale the mechanical response by influencing the number of attached cross-bridges. The significance of the modeling for the interpretation of experimental results is discussed. PMID:4041539

Response of Saw Palmetto to Three Herbicides

Treesearch

J.L. Michael; D.G. Neary

1985-01-01

Saw palmetto [Serona repens (Bartram) Small] can be controlled with herbicides. Garion® 4E1/2 and Brush Killer® 800 were evaluated for effectiveness againest saw palmetto when they were applied at three rates in April, June, and August. Oust® was tested at three rates in April only. Herbicides were not effective with April...

The schedule effect: can recurrent peak infections be reduced without vaccines, quarantines or school closings?

PubMed

Diedrichs, Danilo R; Isihara, Paul A; Buursma, Doeke D

2014-02-01

Using a basic, two transmission level seasonal SIR model, we introduce mathematical evidence for the schedule effect which asserts that major recurring peak infections can be significantly reduced by modification of the traditional school calendar. The schedule effect is observed first in simulated time histories of the infectious population. Schedules with higher average transmission rate may exhibit reduced peak infections. Splitting vacations changes the period of the oscillating transmission function and can confine limit cycles in the proportion susceptible/proportion infected phase plane. Numerical analysis of the phase plane shows the relationship between the transmission period and the maximum recurring infection peaks and period of the response. For certain transmission periods, this response may exhibit period-doubling and chaos, leading to increased peaks. Non-monotonic infectious response is also observed in conjunction with changing birth rate. We discuss how to take these effects into consideration to design an optimum school schedule with particular reference to a hypothetical developing world context. Copyright © 2013 Elsevier Inc. All rights reserved.

[Effects of false memories on the Concealed Information Test].

PubMed

Zaitsu, Wataru

2012-10-01

The effects of false memories on polygraph examinations with the Concealed Information Test (CIT) were investigated by using the Deese-Roediger-McDermott (DRM) paradigm, which allows participants to evoke false memories. Physiological responses to questions consisting of learned, lure, and unlearned items were measured and recorded. The results indicated that responses to lure questions showed critical responses to questions about learned items. These responses included repression of respiration, an increase in electrodermal activity, and a drop in heart rate. These results suggest that critical response patterns are generated in the peripheral nervous system by true and false memories.

Subjective quality evaluation of low-bit-rate video

NASA Astrophysics Data System (ADS)

Masry, Mark; Hemami, Sheila S.; Osberger, Wilfried M.; Rohaly, Ann M.

2001-06-01

A subjective quality evaluation was performed to qualify vie4wre responses to visual defects that appear in low bit rate video at full and reduced frame rates. The stimuli were eight sequences compressed by three motion compensated encoders - Sorenson Video, H.263+ and a Wavelet based coder - operating at five bit/frame rate combinations. The stimulus sequences exhibited obvious coding artifacts whose nature differed across the three coders. The subjective evaluation was performed using the Single Stimulus Continuos Quality Evaluation method of UTI-R Rec. BT.500-8. Viewers watched concatenated coded test sequences and continuously registered the perceived quality using a slider device. Data form 19 viewers was colleted. An analysis of their responses to the presence of various artifacts across the range of possible coding conditions and content is presented. The effects of blockiness and blurriness on perceived quality are examined. The effects of changes in frame rate on perceived quality are found to be related to the nature of the motion in the sequence.

Body-object interaction ratings for 1,618 monosyllabic nouns.

PubMed

Tillotson, Sherri M; Siakaluk, Paul D; Pexman, Penny M

2008-11-01

Body-object interaction (BOI) assesses the ease with which a human body can physically interact with a word's referent. Recent research has shown that BOI influences visual word recognition processes in such a way that responses to high-BOI words (e.g., couch) are faster and less error prone than responses to low-BOI words (e.g., cliff). Importantly, the high-BOI words and the low-BOI words that were used in those studies were matched on imageability. In the present study, we collected BOI ratings for a large set of words. BOI ratings, on a 1-7 scale, were obtained for 1,618 monosyllabic nouns. These ratings allowed us to test the generalizability of BOI effects to a large set of items, and they should be useful to researchers who are interested in manipulating or controlling for the effects of BOI. The body-object interaction ratings for this study may be downloaded from the Psychonomic Society's Archive of Norms, Stimuli, and Data, www.psychonomic.org/archive.

The effects of instructions on the sensitivity of negatively reinforced human behavior to extinction.

PubMed

Alessandri, Jérôme; Cançado, Carlos R X

2017-03-01

The effects of instructions on the sensitivity of negatively reinforced (escape) behavior to extinction were studied. Initially, responding produced timeouts from pressing a force cell on a variable-ratio (VR) schedule, which was then discontinued (extinction). Based on extinction data, participants were distributed into two groups. Participants in the Persistence Group (for which response rates were low in extinction) were instructed that the experimenter expected them to continue responding in extinction after a second exposure to the VR schedule. Participants in the Extinction group (for which response rates were high in extinction) were instructed that the experimenter expected them to stop responding in extinction. Relative to the condition in which instructions were absent, extinction-response rates increased and decreased, respectively, for participants in the Persistence and Extinction groups. These results replicate and extend to negatively reinforced responding previous findings that showed behavioral control by instructions formulated as explicit experimenter demands or expectations. Copyright © 2017 Elsevier B.V. All rights reserved.

Understanding the Implications of a LINAC’s Microstructure on Devices and Photocurrent Models

DOE PAGES

McLain, Michael Lee; McDonald, Joseph Kyle; Hembree, Charles E.; ...

2017-10-20

Here, the effect of a linear accelerator’s (LINAC’s) microstructure (i.e., train of narrow pulses) on devices and the associated transient photocurrent models are investigated. The data indicate that the photocurrent response of Si-based RF bipolar junction transistors and RF p-i-n diodes is considerably higher when taking into account the microstructure effects. Similarly, the response of diamond, SiO 2, and GaAs photoconductive detectors (standard radiation diagnostics) is higher when taking into account the microstructure. This has obvious hardness assurance implications when assessing the transient response of devices because the measured photocurrent and dose rate levels could be underestimated if microstructure effectsmore » are not captured. Indeed, the rate the energy is deposited in a material during the microstructure peaks is much higher than the filtered rate which is traditionally measured. In addition, photocurrent models developed with filtered LINAC data may be inherently inaccurate if a device is able to respond to the microstructure.« less

Understanding the Implications of a LINAC’s Microstructure on Devices and Photocurrent Models

DOE Office of Scientific and Technical Information (OSTI.GOV)

McLain, Michael Lee; McDonald, Joseph Kyle; Hembree, Charles E.

Here, the effect of a linear accelerator’s (LINAC’s) microstructure (i.e., train of narrow pulses) on devices and the associated transient photocurrent models are investigated. The data indicate that the photocurrent response of Si-based RF bipolar junction transistors and RF p-i-n diodes is considerably higher when taking into account the microstructure effects. Similarly, the response of diamond, SiO 2, and GaAs photoconductive detectors (standard radiation diagnostics) is higher when taking into account the microstructure. This has obvious hardness assurance implications when assessing the transient response of devices because the measured photocurrent and dose rate levels could be underestimated if microstructure effectsmore » are not captured. Indeed, the rate the energy is deposited in a material during the microstructure peaks is much higher than the filtered rate which is traditionally measured. In addition, photocurrent models developed with filtered LINAC data may be inherently inaccurate if a device is able to respond to the microstructure.« less

Improving response rates using a monetary incentive for patient completion of questionnaires: an observational study

PubMed Central

Brealey, Stephen D; Atwell, Christine; Bryan, Stirling; Coulton, Simon; Cox, Helen; Cross, Ben; Fylan, Fiona; Garratt, Andrew; Gilbert, Fiona J; Gillan, Maureen GC; Hendry, Maggie; Hood, Kerenza; Houston, Helen; King, David; Morton, Veronica; Orchard, Jo; Robling, Michael; Russell, Ian T; Torgerson, David; Wadsworth, Valerie; Wilkinson, Clare

2007-01-01

Background Poor response rates to postal questionnaires can introduce bias and reduce the statistical power of a study. To improve response rates in our trial in primary care we tested the effect of introducing an unconditional direct payment of £5 for the completion of postal questionnaires. Methods We recruited patients in general practice with knee problems from sites across the United Kingdom. An evidence-based strategy was used to follow-up patients at twelve months with postal questionnaires. This included an unconditional direct payment of £5 to patients for the completion and return of questionnaires. The first 105 patients did not receive the £5 incentive, but the subsequent 442 patients did. We used logistic regression to analyse the effect of introducing a monetary incentive to increase the response to postal questionnaires. Results The response rate following reminders for the historical controls was 78.1% (82 of 105) compared with 88.0% (389 of 442) for those patients who received the £5 payment (diff = 9.9%, 95% CI 2.3% to 19.1%). Direct payments significantly increased the odds of response (adjusted odds ratio = 2.2, 95% CI 1.2 to 4.0, P = 0.009) with only 12 of 442 patients declining the payment. The incentive did not save costs to the trial – the extra cost per additional respondent was almost £50. Conclusion The direct payment of £5 significantly increased the completion of postal questionnaires at negligible increase in cost for an adequately powered study. PMID:17326837

[Efficacy of infliximab in the treatment of korean patients with crohns disease].

PubMed

Kim, Sai Hui; Yang, Suk; Kim, Kyung Jo; Kim, Eun Hee; Yoon, Soon Man; Ye, Byong Duk; Byeon, Jeong Sik; Myung, Seung Jae; Kim, Jin Ho

2009-08-01

Infliximab has been proven to be effective for refractory luminal and fistulizing Crohns disease (CD). We performed this study to demonstrate the efficacy of infliximab in Korean CD patients. Medical records of 40 CD patients who had been treated with infliximab were reviewed retrospectively. Among 40 patients, 11 (27.5%) patients were treated for refractory luminal disease, 14 (35%) for fistulizing disease, and 15 (37.5%) for both types. Clinical response rate was higher in 26 patients with refractory luminal disease (Complete response (CR), 73.1%; Partial response (PR), 23.1%) than in 29 patients with fistulizing disease (CR, 41.4%; PR, 31%) (p=0.024). The clinical response rate tended to be higher in 28 patients with external fistulas (CR, 46.4%; PR, 32.2%) than 4 patients with internal fistulas (PR, 25%; NR, 75%) (p=0.064). Among patients with external fistulas, the response rate of 8 patients with enterocutaneous fistulas (CR, 50%; PR, 12.5%) was not different from 20 patients with perianal fistulas (CR, 45%; PR, 40%). Among 20 patients with perianal fistulas, the response rate of 6 patients with perianal fistulas without a history of operation (CR, 83.3%; PR, 0%) was higher than 14 patients with perianal fistulas resistant to previous surgical treatment (CR, 28.6%; PR, 57.1%) (p=0.044). As for adverse reaction, 7 patients experienced mild infusion reaction, and 2 patients developed serious infection. Infliximab is more effective for refractory luminal disease than for fistulizing disease. In addition, clinical responses to infliximab are different according to subtypes of fistulas. These findings should be considered for the proper use of infliximab.

Cognitive-behavioral therapy as continuation treatment to sustain response after electroconvulsive therapy in depression: a randomized controlled trial.

PubMed

Brakemeier, Eva-Lotta; Merkl, Angela; Wilbertz, Gregor; Quante, Arnim; Regen, Francesca; Bührsch, Nicole; van Hall, Franziska; Kischkel, Eva; Danker-Hopfe, Heidi; Anghelescu, Ion; Heuser, Isabella; Kathmann, Norbert; Bajbouj, Malek

2014-08-01

Although electroconvulsive therapy (ECT) is the most effective acute antidepressant intervention, sustained response rates are low. It has never been systematically assessed whether psychotherapy, continuation ECT, or antidepressant medication is the most efficacious intervention to maintain initial treatment response. In a prospective, randomized clinical trial, 90 inpatients with major depressive disorder (MDD) were treated with right unilateral ultra-brief acute ECT. Electroconvulsive therapy responders received 6 months guideline-based antidepressant medication (MED) and were randomly assigned to add-on therapy with cognitive-behavioral group therapy (CBT-arm), add-on therapy with ultra-brief pulse continuation electroconvulsive therapy (ECT-arm), or no add-on therapy (MED-arm). After the 6 months of continuation treatment, patients were followed-up for another 6 months. The primary outcome parameter was the proportion of patients who remained well after 12 months. Of 90 MDD patients starting the acute phase, 70% responded and 47% remitted to acute ECT. After 6 months of continuation treatment, significant differences were observed in the three treatment arms with sustained response rates of 77% in the CBT-arm, 40% in the ECT-arm, and 44% in the MED-arm. After 12 months, these differences remained stable with sustained response rates of 65% in the CBT-arm, 28% in the ECT-arm, and 33% in the MED-arm. These results suggest that ultra-brief pulse ECT as a continuation treatment correlates with low sustained response rates. However, the main finding implicates cognitive-behavioral group therapy in combination with antidepressants might be an effective continuation treatment to sustain response after successful ECT in MDD patients. Copyright © 2014 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Variability in solar radiation and temperature explains observed patterns and trends in tree growth rates across four tropical forests.

PubMed

Dong, Shirley Xiaobi; Davies, Stuart J; Ashton, Peter S; Bunyavejchewin, Sarayudh; Supardi, M N Nur; Kassim, Abd Rahman; Tan, Sylvester; Moorcroft, Paul R

2012-10-07

The response of tropical forests to global climate variability and change remains poorly understood. Results from long-term studies of permanent forest plots have reported different, and in some cases opposing trends in tropical forest dynamics. In this study, we examined changes in tree growth rates at four long-term permanent tropical forest research plots in relation to variation in solar radiation, temperature and precipitation. Temporal variation in the stand-level growth rates measured at five-year intervals was found to be positively correlated with variation in incoming solar radiation and negatively related to temporal variation in night-time temperatures. Taken alone, neither solar radiation variability nor the effects of night-time temperatures can account for the observed temporal variation in tree growth rates across sites, but when considered together, these two climate variables account for most of the observed temporal variability in tree growth rates. Further analysis indicates that the stand-level response is primarily driven by the responses of smaller-sized trees (less than 20 cm in diameter). The combined temperature and radiation responses identified in this study provide a potential explanation for the conflicting patterns in tree growth rates found in previous studies.

The acute physiological and mood effects of tea and coffee: the role of caffeine level.

PubMed

Quinlan, P T; Lane, J; Moore, K L; Aspen, J; Rycroft, J A; O'Brien, D C

2000-05-01

The objective of this study was to determine the effect of caffeine level in tea and coffee on acute physiological responses and mood. Randomised full crossover design in subjects after overnight caffeine abstention was studied. In study 1 (n = 17) the caffeine level was manipulated naturalistically by preparing tea and coffee at different strengths (1 or 2 cups equivalent). Caffeine levels were 37.5 and 75 mg in tea, 75 and 150 mg in coffee, with water and no-drink controls. In study 2 (n = 15) caffeine level alone was manipulated (water, decaffeinated tea, plus 0, 25, 50, 100, and 200 mg caffeine). Beverage volume and temperature (55 degrees C) were constant. SBP, DBP, heart rate, skin temperature, skin conductance, and mood were monitored over each 3-h study session. In study 1, tea and coffee produced mild autonomic stimulation and an elevation in mood. There were no effects of tea vs. coffee or caffeine dose, despite a fourfold variation in the latter. Increasing beverage strength was associated with greater increases in DBP and energetic arousal. In study 2, caffeinated beverages increased SBP, DBP, and skin conductance and lowered heart rate and skin temperature compared to water. Significant dose-response relationships to caffeine were seen only for SBP, heart rate, and skin temperature. There were significant effects of caffeine on energetic arousal but no consistent dose-response effects. Caffeinated beverages acutely stimulate the autonomic nervous system and increase alertness. Although caffeine can exert dose-dependent effects on a number of acute autonomic responses, caffeine level is not an important factor. Factors besides caffeine may contribute to these acute effects.

Effects of Method of Instruction and Frequency of Response on Criterion Performance

ERIC Educational Resources Information Center

Troost, Cornelius J.; Morris, Stanley

1971-01-01

Grade six students were taught Newton's Second Law of Motion by a linear program, a lecture, or a video-taped lecture, with three different response modes: written responses to all questions, to one-third of the questions, or to no questions. There was no significant difference between teaching method, but the higher the overt response rate, the…

Acute changes in the central nervous system of monkeys exposed to protons.

NASA Technical Reports Server (NTRS)

Haymaker, W.; Ibrahim, M. Z. M.; Miquel, J.; Call, N.; Noden, P.; Ashley, W.; Ballinger, E. R.; Ghidoni, J.; Lindsay, I. R.; Behar, A. J.

1972-01-01

Study of the changes occurring in simian brain exposed to protons of varied energy, given in wide dose and dose-rate ranges. Results show that inflammatory reaction and glycogen accumulation in astrocytes occurred practically in all animals. Cerebral cortical necrosis, granule cell pyknosis, and inflammatory reaction occurred at doses far lower than effective for high-energy gamma radiation given other series of monkeys at comparable dose rates. Metallic impregnation, carried out in virtually all the animals tested, revealed a wide variation in glial response even at equal doses and dose rates in the same proton energy series. Proton energy effect, dose effect, dose-time effect, and dose-rate effect were evident in the various morphological categories investigated, but inconsistencies were encountered.

Responses to deceleration during car following: roles of optic flow, warnings, expectations, and interruptions.

PubMed

DeLucia, Patricia R; Tharanathan, Anand

2009-12-01

More than 25% of accidents are rear-end collisions. It is essential to identify the factors that contribute to such collisions. One such factor is a driver's ability to respond to the deceleration of the car ahead. In Experiment 1, we measured effects of optic flow information and discrete visual and auditory warnings (brake lights, tones) on responses to deceleration during car following. With computer simulations of car-following scenes, university students pressed a button when the lead car decelerated. Both classes of information affected responses. Observers relied on discrete warnings when optic flow information was relatively less effective as determined by the lead car's headway and deceleration rate. This is consistent with DeLucia's (2008) conceptual framework of space perception that emphasized the importance of viewing distance and motion (and task). In Experiment 2, we measured responses to deceleration after a visual interruption. Scenes were designed to tease apart the role of expectations and optic flow. Responses mostly were consistent with optic flow information presented after the interruption rather than with putative mental expectations that were set up by the lead car's motion prior to the interruption. The theoretical implication of the present results is that responses to deceleration are based on multiple sources of information, including optical size, optical expansion rate and tau, and discrete warnings that are independent of optic flow. The practical implication is that in-vehicle collision-avoidance warning systems may be more useful when optic flow is less effective (e.g., slow deceleration rates), implicating a role for adaptive collision-warning systems. Copyright 2009 APA

Top-down and bottom-up modulation of language related areas – An fMRI Study

PubMed Central

Noesselt, Tömme; Shah, Nadim Jon; Jäncke, Lutz

2003-01-01

Background One major problem for cognitive neuroscience is to describe the interaction between stimulus and task driven neural modulation. We used fMRI to investigate this interaction in the human brain. Ten male subjects performed a passive listening and a semantic categorization task in a factorial design. In both tasks, words were presented auditorily at three different rates. Results We found: (i) as word presentation rate increased hemodynamic responses increased bilaterally in the superior temporal gyrus including Heschl's gyrus (HG), the planum temporale (PT), and the planum polare (PP); (ii) compared to passive listening, semantic categorization produced increased bilateral activations in the ventral inferior frontal gyrus (IFG) and middle frontal gyrus (MFG); (iii) hemodynamic responses in the left dorsal IFG increased linearly with increasing word presentation rate only during the semantic categorization task; (iv) in the semantic task hemodynamic responses decreased bilaterally in the insula with increasing word presentation rates; and (v) in parts of the HG the hemodynamic response increased with increasing word presentation rates during passive listening more strongly. Conclusion The observed "rate effect" in primary and secondary auditory cortex is in accord with previous findings and suggests that these areas are driven by low-level stimulus attributes. The bilateral effect of semantic categorization is also in accord with previous studies and emphasizes the role of these areas in semantic operations. The interaction between semantic categorization and word presentation in the left IFG indicates that this area has linguistic functions not present in the right IFG. Finally, we speculate that the interaction between semantic categorization and word presentation rates in HG and the insula might reflect an inhibition of the transfer of unnecessary information from the temporal to frontal regions of the brain. PMID:12828789

Differential response to alcohol in light and moderate female social drinkers.

PubMed

Evans, S M; Levin, F R

2004-05-01

Individuals who are moderate drinkers are at increased risk to abuse alcohol. Moreover, women are more vulnerable than men to the adverse consequences of alcohol consumption and recent data indicate that the drinking pattern in women is becoming more similar to that of men. However, few studies have determined whether female moderate drinkers (MD) show a differential response to the subjective and performance effects of alcohol, compared to female light drinkers (LD). Fifteen female MD who consumed an average of 34.7 drinks/month were compared to 15 female LD who consumed an average of 6.7 drinks/month. None of the participants had a first-degree family history of alcoholism or substance abuse. The acute effects of alcohol (0, 0.25, 0.50, 0.75 mg/kg) were evaluated using a double-blind, placebo-controlled outpatient design. Drug effects were assessed using a full range of performance measures, subjective-effects questionnaires and observer ratings. Alcohol impaired performance in a dose-related manner on all performance tasks for both groups of females. However, MD were less impaired than LD on balance and Digit Symbol Substitution Test (DSST). This reduced response was also evident from the observer ratings, with MD being viewed as less impaired by alcohol than LD. While ratings of Drug Liking increased in both groups of women on the ascending limb of the breath alcohol curve, alcohol was disliked by LD on the descending limb and LD reported increased ratings of Bad Drug Effects following the high dose of alcohol. The reduced performance impairment, coupled with the positive subjective effects and relative absence of adverse subjective effects, suggestive of behavioral tolerance, could result in a progression towards increased alcohol consumption among moderate female social drinkers.

Acute changes in community violence and increases in hospital visits and deaths from stress-responsive diseases.

PubMed

Ahern, Jennifer; Matthay, Ellicott C; Goin, Dana E; Farkas, Kriszta; Rudolph, Kara E

2018-06-06

Community violence may affect a broad range of health outcomes through physiologic stress responses and changes in health behaviors among residents. However, existing research on the health impacts of community violence suffers from problems with bias. We examined the relations of acute changes in community violence with hospital visits and deaths due to stress-responsive diseases (mental, respiratory, and cardiac conditions) in statewide data from California 2005-2013. The community violence exposure was measured as both binary spikes and continuous acute changes. We applied a combined fixed-effects and time-series design that separates the effects of violence from those of community- and individual-level confounders more effectively than past research. Temporal patterning was removed from community violence rates and disease rates in each place using a Kalman smoother, resulting in residual rates. We used linear regression with place fixed-effects to examine within-place associations of acute changes in community violence with residual rates of each outcome, controlling for local time-varying covariates. We found acute increases in hospital visits and deaths due to anxiety disorders (0.31 per 100,000; 95% Confidence Interval (CI) 0.02,0.59), substance use (0.47 per 100,000; 95%CI 0.14,0.80), asthma (0.56 per 100,000; 95%CI 0.16,0.95), and fatal acute myocardial infarction (0.09 per 100,000; 95%CI 0.00,0.18) co-occurring with violence spikes. The pattern of findings was similar for the exposure of continuous acute violence changes. Although the associations were small, the identified increases in stress-responsive conditions suggest the possibility of health impacts of acute changes in community violence.

Modeling the intracellular pathogen-immune interaction with cure rate

NASA Astrophysics Data System (ADS)

Dubey, Balram; Dubey, Preeti; Dubey, Uma S.

2016-09-01

Many common and emergent infectious diseases like Influenza, SARS, Hepatitis, Ebola etc. are caused by viral pathogens. These infections can be controlled or prevented by understanding the dynamics of pathogen-immune interaction in vivo. In this paper, interaction of pathogens with uninfected and infected cells in presence or absence of immune response are considered in four different cases. In the first case, the model considers the saturated nonlinear infection rate and linear cure rate without absorption of pathogens into uninfected cells and without immune response. The next model considers the effect of absorption of pathogens into uninfected cells while all other terms are same as in the first case. The third model incorporates innate immune response, humoral immune response and Cytotoxic T lymphocytes (CTL) mediated immune response with cure rate and without absorption of pathogens into uninfected cells. The last model is an extension of the third model in which the effect of absorption of pathogens into uninfected cells has been considered. Positivity and boundedness of solutions are established to ensure the well-posedness of the problem. It has been found that all the four models have two equilibria, namely, pathogen-free equilibrium point and pathogen-present equilibrium point. In each case, stability analysis of each equilibrium point is investigated. Pathogen-free equilibrium is globally asymptotically stable when basic reproduction number is less or equal to unity. This implies that control or prevention of infection is independent of initial concentration of uninfected cells, infected cells, pathogens and immune responses in the body. The proposed models show that introduction of immune response and cure rate strongly affects the stability behavior of the system. Further, on computing basic reproduction number, it has been found to be minimum for the fourth model vis-a-vis other models. The analytical findings of each model have been exemplified by numerical simulations.

Applying Fuzzy Data Mining to Telecom Churn Management

NASA Astrophysics Data System (ADS)

Liao, Kuo-Hsiung; Chueh, Hao-En

Customers tend to change telecommunications service providers in pursuit of more favorable telecommunication rates. Therefore, how to avoid customer churn is an extremely critical topic for the intensely competitive telecommunications industry. To assist telecommunications service providers in effectively reducing the rate of customer churn, this study used fuzzy data mining to determine effective marketing strategies by analyzing the responses of customers to various marketing activities. These techniques can help telecommunications service providers determine the most appropriate marketing opportunities and methods for different customer groups, to reduce effectively the rate of customer turnover.

Impact of pretreatment with antidepressants on the efficacy of duloxetine in terms of mood symptoms and functioning: an analysis of 15 pooled major depressive disorder studies.

PubMed

Barros, Bruno R; Schacht, Alexander; Happich, Michael; Televantou, Foula; Berggren, Lovisa; Walker, Daniel J; Dueñas, Hector J

2014-01-01

This post hoc analysis aimed to determine whether patients with major depressive disorder (MDD) in duloxetine trials who were antidepressant naive or who were previously exposed to antidepressants exhibited differences in efficacy and functioning. Data were pooled from 15 double-blind, placebo- and/or active-controlled duloxetine trials of adult patients with MDD conducted by Eli Lilly and Company. The individual studies took place between March 2000 and November 2009. Data were analyzed using 4 pretreatment subgroups: first-episode never treated, multiple-episode never treated, treated previously only with selective serotonin reuptake inhibitors (SSRIs), and previously treated with antidepressants other than just SSRIs. Measures included the 17-item Hamilton Depression Rating Scale (HDRS-17) total and somatic symptom subscale scores, Montgomery-Asberg Depression Rating Scale (MADRS) total score, and Sheehan Disability Scale total score. Response rates (50% and 30%) were based on the HDRS-17 total score and remission rates on either the HDRS-17 or MADRS total score. Response and remission rates were significantly greater (P < .05 in 11 of 12 comparisons) for duloxetine versus placebo in the 4 subgroups. A trend of greater response and remission occurred for first-episode versus multiple-episode patients; both groups were generally higher than the antidepressant-treated groups. Mean changes in efficacy measures were mostly significantly greater (P < .05 in 13 of 16 comparisons) for duloxetine versus placebo within each pretreatment subgroup, with some (P < .05 in 2 of 24 comparisons) significant interaction effects between subgroups on HDRS-17 total and somatic symptoms scores. Duloxetine was generally superior to placebo on response and remission rates and in mean change on efficacy measures. Response and remission rates were numerically greater for first-episode versus multiple-episode and drug-treated patients. Mean change differences on efficacy measures among the 4 subgroups were inconsistent. Duloxetine showed a similar therapeutic effect independent of episode frequency and antidepressant pretreatment.

LDR brachytherapy: can low dose rate hypersensitivity from the "inverse" dose rate effect cause excessive cell killing to peripherial connective tissues and organs?

PubMed

Leonard, B E; Lucas, A C

2009-02-01

Examined here are the possible effects of the "inverse" dose rate effect (IDRE) on low dose rate (LDR) brachytherapy. The hyper-radiosensitivity and induced radioresistance (HRS/IRR) effect benefits cell killing in radiotherapy, and IDRE and HRS/IRR seem to be generated from the same radioprotective mechanisms. We have computed the IDRE excess cell killing experienced in LDR brachytherapy using permanent seed implants. We conclude, firstly, that IDRE is a dose rate-dependent manifestation of HRS/IRR. Secondly, the presence of HRS/IRR or IDRE in a cell species or tissue must be determined by direct dose-response measurements. Thirdly, a reasonable estimate is that 50-80% of human adjoining connective and organ tissues experience IDRE from permanent implanted LDR brachytherapy. If IDRE occurs for tissues at point A for cervical cancer, the excess cell killing will be about a factor of 3.5-4.0 if the initial dose rate is 50-70 cGy h(-1). It is greater for adjacent tissues at lower dose rates and higher for lower initial dose rates at point A. Finally, higher post-treatment complications are observed in LDR brachytherapy, often for unknown reasons. Some of these are probably a result of IDRE excess cell killing. Measurements of IDRE need be performed for connective and adjacent organ tissues, i.e. bladder, rectum, urinary tract and small bowels. The measured dose rate-dependent dose responses should extended to <10 cGy h(-1) and involve multiple patients to detect patient variability. Results may suggest a preference for high dose rate brachytherapy or LDR brachytherapy without permanent retention of the implant seeds (hence the dose rates in peripheral tissues and organs remain above IDRE thresholds).

A model of clearance rate regulation in mussels

NASA Astrophysics Data System (ADS)

Fréchette, Marcel

2012-10-01

Clearance rate regulation has been modelled as an instantaneous response to food availability, independent of the internal state of the animals. This view is incompatible with latent effects during ontogeny and phenotypic flexibility in clearance rate. Internal-state regulation of clearance rate is required to account for these patterns. Here I develop a model of internal-state based regulation of clearance rate. External factors such as suspended sediments are included in the model. To assess the relative merits of instantaneous regulation and internal-state regulation, I modelled blue mussel clearance rate and growth using a DEB model. In the usual standard feeding module, feeding is governed by a Holling's Type II response to food concentration. In the internal-state feeding module, gill ciliary activity and thus clearance rate are driven by internal reserve level. Factors such as suspended sediments were not included in the simulations. The two feeding modules were compared on the basis of their ability to capture the impact of latent effects, of environmental heterogeneity in food abundance and of physiological flexibility on clearance rate and individual growth. The Holling feeding module was unable to capture the effect of any of these sources of variability. In contrast, the internal-state feeding module did so without any modification or ad hoc calibration. Latent effects, however, appeared transient. With simple annual variability in temperature and food concentration, the relationship between clearance rate and food availability predicted by the internal-state feeding module was quite similar to that observed in Norwegian fjords. I conclude that in contrast with the usual Holling feeding module, internal-state regulation of clearance rate is consistent with well-documented growth and clearance rate patterns.

Foot and hand massage as an intervention for postoperative pain.

PubMed

Wang, Hsiao-Lan; Keck, Juanita F

2004-06-01

Physiological responses to pain create harmful effects that prolong the body's recovery after surgery. Patients routinely report mild to moderate pain even though pain medications have been administered. Complementary strategies based on sound research findings are needed to supplement postoperative pain relief using pharmacologic management. Foot and hand massage has the potential to assist in pain relief. Massaging the feet and hands stimulates the mechanoreceptors that activate the "nonpainful" nerve fibers, preventing pain transmission from reaching consciousness. The purpose of this pretest-posttest design study was to investigate whether a 20-minute foot and hand massage (5 minutes to each extremity), which was provided 1 to 4 hours after a dose of pain medication, would reduce pain perception and sympathetic responses among postoperative patients. A convenience sample of 18 patients rated pain intensity and pain distress using a 0 to 10 numeric rating scale. They reported decreases in pain intensity from 4.65 to 2.35 (t = 8.154, p <.001) and in pain distress from 4.00 to 1.88 (t = 5.683, p <.001). Statistically significant decreases in sympathetic responses to pain (i.e., heart rate and respiratory rate) were observed although blood pressure remained unchanged. The changes in heart rate and respiratory rate were not clinically significant. The patients experienced moderate pain after they received pain medications. This pain was reduced by the intervention, thus supporting the effectiveness of massage in postoperative pain management. Foot and hand massage appears to be an effective, inexpensive, low-risk, flexible, and easily applied strategy for postoperative pain management.

Placebo and nocebo reactions in randomized trials of pharmacological treatments for persistent depressive disorder. A meta-regression analysis.

PubMed

Meister, Ramona; Jansen, Alessa; Härter, Martin; Nestoriuc, Yvonne; Kriston, Levente

2017-06-01

We aimed to investigate placebo and nocebo reactions in randomized controlled trials (RCT) of pharmacological treatments for persistent depressive disorder (PDD). We conducted a systematic electronic search and included RCTs investigating antidepressants for the treatment of PDD. Outcomes were the number of patients experiencing response and remission in placebo arms (=placebo reaction). Additional outcomes were the incidence of patients experiencing adverse events and related discontinuations in placebo arms (=nocebo reaction). A priori defined effect modifiers were analyzed using a series of meta-regression analyses. Twenty-three trials were included in the analyses. We found a pooled placebo response rate of 31% and a placebo remission rate of 22%. The pooled adverse event rate and related discontinuations were 57% and 4%, respectively. All placebo arm outcomes were positively associated with the corresponding medication arm outcomes. Placebo response rate was associated with a greater proportion of patients with early onset depression, a smaller chance to receive placebo and a larger sample size. The adverse event rate in placebo arms was associated with a greater proportion of patients with early onset depression, a smaller proportion of females and a more recent publication. Pooled placebo and nocebo reaction rates in PDD were comparable to those in episodic depression. The identified effect modifiers should be considered to assess unbiased effects in RCTs, to influence placebo and nocebo reactions in practice. Limitations result from the methodology applied, the fact that we conducted only univariate analyses, and the number and quality of included trials. Copyright © 2017 Elsevier B.V. All rights reserved.

User-experience surveys with maternity services: a randomized comparison of two data collection models.

PubMed

Bjertnaes, Oyvind Andresen; Iversen, Hilde Hestad

2012-08-01

To compare two ways of combining postal and electronic data collection for a maternity services user-experience survey. Cross-sectional survey. Maternity services in Norway. All women who gave birth at a university hospital in Norway between 1 June and 27 July 2010. Patients were randomized into the following groups (n= 752): Group A, who were posted questionnaires with both electronic and paper response options for both the initial and reminder postal requests; and Group B, who were posted questionnaires with an electronic response option for the initial request, and both electronic and paper response options for the reminder postal request. Response rate, the amount of difference in background variables between respondents and non-respondents, main study results and estimated cost-effectiveness. The final response rate was significantly higher in Group A (51.9%) than Group B (41.1%). None of the background variables differed significantly between the respondents and non-respondents in Group A, while two variables differed significantly between the respondents and non-respondents in Group B. None of the 11 user-experience scales differed significantly between Groups A and B. The estimated costs per response for the forthcoming national survey was €11.7 for data collection Model A and €9.0 for Model B. The model with electronic-only response option in the first request had lowest response rate. However, this model performed equal to the other model on non-response bias and better on estimated cost-effectiveness, and is the better of the two models in large-scale user experiences surveys with maternity services.

Can supine recovery mitigate the exercise intensity dependent attenuation of post-exercise heat loss responses?

PubMed

Kenny, Glen P; Gagnon, Daniel; Jay, Ollie; McInnis, Natalie H; Journeay, W Shane; Reardon, Francis D

2008-08-01

Cutaneous vascular conductance (CVC) and sweat rate are subject to non-thermal baroreflex-mediated attenuation post-exercise. Various recovery modalities have been effective in attenuating these decreases in CVC and sweat rate post-exercise. However, the interaction of recovery posture and preceding exercise intensity on post-exercise thermoregulation remains unresolved. We evaluated the combined effect of supine recovery and exercise intensity on post-exercise cardiovascular and thermal responses relative to an upright seated posture. Seven females performed 15 min of cycling ergometry at low- (LIE, 55% maximal oxygen consumption) or high-(HIE, 85% maximal oxygen consumption) intensity followed by 60 min of recovery in either an upright seated or supine posture. Esophageal temperature, CVC, sweat rate, cardiac output, stroke volume, heart rate, total peripheral resistance, and mean arterial pressure (MAP) were measured at baseline, at end-exercise, and at 2, 5, 12, 20, and every 10 min thereafter until the end of recovery. MAP and stroke volume were maintained during supine recovery to a greater extent relative to an upright seated recovery following HIE (p

Cardiovascular responses during orthostasis - Effect of an increase in maximal O2 uptake

NASA Technical Reports Server (NTRS)

Convertino, V. A.; Montgomery, L. D.; Greenleaf, J. E.

1984-01-01

A study is described which tests the hypothesis that changes in aerobic activity (increases in maximum oxygen uptake) will reduce the effectiveness of cardiovascular reflexes to regulate blood pressure during orthostasis. The hypothesis was tested by measuring heart rate, blood pressure and blood volume responses in eight healthy male subjects before and after an eight-day endurance regimen. The results of the study suggest that the physiologic responses to orthostasis are dependent upon the rate of plasma volume loss and pooling, and are associated with training-induced hypervolemia. It is indicated that endurance type exercise training enhances cardiovascular adjustments during tilt. The implications of these results for the use of exercise training as a countermeasure and/or therapeutic method for the prevention of cardiovascular instability during orthostatic stress are discussed.

The Motive for Support and the Identification of Responsive Partners

PubMed Central

Turan, Bulent; Horowitz, Leonard M.

2010-01-01

To obtain support from others, a person must first identify responsive partners. One strategy for doing so is to use indicators of responsive partners. We argue that a person with a strong motive for support should rate all indicators highly useful—the “Elevated Motives Effect.” Study 1 confirmed this hypothesis by correlating participants’ total ratings with existing measures of motive-strength. Study 2 applied the Elevated Motives Effect to demonstrate that motive-strength (in interaction with knowledge of indicators) predicts performance on a laboratory task in which participants evaluated a person: Superior knowledge led to superior performance only when motive-strength was high. Study 3, an experience-sampling study, showed that in everyday life, motivated people more often seek support from others when distressed. PMID:20544011

Increasing the Response Rate of the Patient Satisfaction Survey of Inpatients at National Naval Medical Center

DTIC Science & Technology

1993-08-01

identify a method to improve the effectiveness of the current survey process to increase the response rate of the patients being sampled. As health care... consumer must have adequate representation to provide meaningful information for decision making by the health care organization. Background of the...the Total Quality Management (TQM) philosophy into the health care industry has increased the importance of listening to the customer (Matthews, 1992

Effects of Disturbance on Populations of Marine Mammals

DTIC Science & Technology

2014-09-30

relation between foraging success of mothers and pup production (reproductive rate). Second, we we used mark-recapture models to quantify the...responses to disturbance are not necessarily surrogate measures of population-level responses is widely understood. However, without tractable

Constraining response output on conjunctive fixed-ratio 1 fixed-time reinforcement schedules: Effects on the postreinforcement pause.

PubMed

Lopez, F; Pereira, C

1985-03-01

Two experiments used response-restriction procedures in order to test the independence of the factors determining response rate and the factors determining the size of the postreinforcement pause on interval schedules. Responding was restricted by response-produced blackout or by retracting the lever. In Experiment 1 with a Conjunctive FR 1 FT schedule, the blackout procedure reduced the postreinforcement pause more than the lever-retraction procedure did, and both procedures produced shorter pauses than did the schedule without response restriction. In Experiment 2 the interreinforcement interval was also manipulated, and the size of the pause was an increasing function of the interreinforcement interval, but the rate of increase was lower than that produced by fixed interval schedules of comparable interval durations. The assumption of functional independence of the postreinforcement pause and terminal rate in fixed interval schedules is questioned since data suggest that pause reductions resulted from constraining variation in response number compared to equivalent periodic schedules in which response number was allowed to vary. Copyright © 1985. Published by Elsevier B.V.

Effects of aircraft noise on human sleep.

NASA Technical Reports Server (NTRS)

Lukas, J. S.

1972-01-01

Under controlled conditions in two test rooms, studies were made of the response of sleeping subjects to the stimuli of simulated sonic booms and subsonic jet aircraft noise. Children were relatively nonresponsive to the stimuli. In general, the older the subject, the more likely is behavioral awakening. The response rates to the two types of stimuli were essentially the same. The stimulus intensity had little, if any, effect on frequency of arousal, although other degrees of response did increase.

Effects of heat and other inducers of the stress response on protein degradation in Chinese hamster and Drosophila cells.

PubMed

Westwood, J T; Steinhardt, R A

1989-04-01

Many recent studies have suggested that heat and other inducers of the heat shock (stress) response in eukaryotic cells might result in the generation of abnormal proteins which would result in the overloading of protein degradation systems and the stabilization of proteins involved in positively regulating heat shock (hs) gene expression. In this study we have examined the effects different heat treatments and other hs inducers have on protein degradation in Chinese hamster ovary (CHO) and Drosophila Kc and Schneider cells. We have found that intermediate temperatures which induced the hs response (42 degrees C in CHO and 34 degrees C in Kc cells) did increase protein degradation rates whereas, higher temperatures which also induced the hs response (45 degrees C in CHO and 37 degrees C in Kc cells) initially increased but then decreased protein degradation rates. While these results are consistent with a model in which the protein degradation system is being overloaded and/or components of it are being depleted, we have found several conditions which induce hs proteins which rule out this mechanism. Exposure of either cell type to amino acid analogs (5 mM canavanine or 5 mM S-aminoethyl cysteine) resulted in the rapid degradation of those proteins which had incorporated the analogs in both CHO and Drosophila cells. However, the addition of analogs had little or no effect on the degradation of preexisting proteins, indicating that the introduction of abnormal proteins probably didn't overload the protein degradation system(s). The addition of 100 microM cadmium sulfate or 100 microM sodium arsenite had little or no effect on protein degradation rates in CHO cells even though both were good inducers of the hs proteins. Thus, exposure to inducers of the hs response does not universally increase protein degradation rates nor does it stabilize preexisting proteins. Therefore, the degradation of abnormal proteins is probably not involved in inducing the hs genes.

Quantitative Modeling of Microbial Population Responses to Chronic Irradiation Combined with Other Stressors

PubMed Central

Shuryak, Igor; Dadachova, Ekaterina

2016-01-01

Microbial population responses to combined effects of chronic irradiation and other stressors (chemical contaminants, other sub-optimal conditions) are important for ecosystem functioning and bioremediation in radionuclide-contaminated areas. Quantitative mathematical modeling can improve our understanding of these phenomena. To identify general patterns of microbial responses to multiple stressors in radioactive environments, we analyzed three data sets on: (1) bacteria isolated from soil contaminated by nuclear waste at the Hanford site (USA); (2) fungi isolated from the Chernobyl nuclear-power plant (Ukraine) buildings after the accident; (3) yeast subjected to continuous γ-irradiation in the laboratory, where radiation dose rate and cell removal rate were independently varied. We applied generalized linear mixed-effects models to describe the first two data sets, whereas the third data set was amenable to mechanistic modeling using differential equations. Machine learning and information-theoretic approaches were used to select the best-supported formalism(s) among biologically-plausible alternatives. Our analysis suggests the following: (1) Both radionuclides and co-occurring chemical contaminants (e.g. NO2) are important for explaining microbial responses to radioactive contamination. (2) Radionuclides may produce non-monotonic dose responses: stimulation of microbial growth at low concentrations vs. inhibition at higher ones. (3) The extinction-defining critical radiation dose rate is dramatically lowered by additional stressors. (4) Reproduction suppression by radiation can be more important for determining the critical dose rate, than radiation-induced cell mortality. In conclusion, the modeling approaches used here on three diverse data sets provide insight into explaining and predicting multi-stressor effects on microbial communities: (1) the most severe effects (e.g. extinction) on microbial populations may occur when unfavorable environmental conditions (e.g. fluctuations of temperature and/or nutrient levels) coincide with radioactive contamination; (2) an organism’s radioresistance and bioremediation efficiency in rich laboratory media may be insufficient to carry out radionuclide bioremediation in the field—robustness against multiple stressors is needed. PMID:26808049

Intertrial-interval effects on sensitivity (A') and response bias (B") in a temporal discrimination by rats.

PubMed Central

Raslear, T G; Shurtleff, D; Simmons, L

1992-01-01

Killeen and Fetterman's (1988) behavioral theory of animal timing predicts that decreases in the rate of reinforcement should produce decreases in the sensitivity (A') of temporal discriminations and a decrease in miss and correct rejection rates (decrease in bias toward "long" responses). Eight rats were trained on a 10- versus 0.1-s temporal discrimination with an intertrial interval of 5 s and were subsequently tested on probe days on the same discrimination with intertrial intervals of 1, 2.5, 5, 10, or 20 s. The rate of reinforcement declined for all animals as intertrial interval increased. Although sensitivity (A') decreased with increasing intertrial interval, all rats showed an increase in bias to make long responses. PMID:1447544

Temozolomide is an active agent in children with recurrent medulloblastoma/primitive neuroectodermal tumor: an Italian multi-institutional phase II trial.

PubMed

Cefalo, Graziella; Massimino, Maura; Ruggiero, Antonio; Barone, Giuseppe; Ridola, Vita; Spreafico, Filippo; Potepan, Paolo; Abate, Massimo E; Mascarin, Maurizio; Garrè, Maria Luisa; Perilongo, Giorgio; Madon, Enrico; Colosimo, Cesare; Riccardi, Riccardo

2014-05-01

The aim of this study was to assess the objective response rate (ORR) of children and young adults with recurrent medulloblastoma/primitive neuroectodermal tumor (MB/PNET) treated with temozolomide (TMZ). The secondary purpose was to analyze the toxicity profile of TMZ when administered orally for 5 days in 3 divided daily doses every 28 days. Forty-two patients with recurrent MB/PNET, aged 21 years and younger, were recruited. Patients were treated with oral TMZ. Starting doses ranged from 120 to 200 mg/m(2)/day based on previous treatments. A craniospinal MRI was performed prior to the first cycle of TMZ and following every 2 cycles of treatment. Median age was 10 years (range, 2-21 years). Forty of 42 patients were assessed for response and toxicity. The objective response rate was 42.5%: 6 patients achieved a complete response, 11 had a partial response, and 10 had stable disease. Progression-free survival rates for all patients at 6 and 12 months were 30% and 7.5%, respectively. Their median overall survival rates at 6 and 12 months were 42.5% and 17.5%, respectively. No major extrahematological effects or life-threatening events were reported. The most common grade 3/4 toxicity included thrombocytopenia (17.5%), neutropenia (7.5%), and anemia (2.5%). TMZ proved to be an effective agent in children and young adults with MB/PNET, heavily pre-treated, with a tolerable toxicity profile.

Variability of Thermosphere and Ionosphere Responses to Solar Flares

NASA Technical Reports Server (NTRS)

Qian, Liying; Burns, Alan G.; Chamberlin, Philip C.; Solomon, Stanley C.

2011-01-01

We investigated how the rise rate and decay rate of solar flares affect the thermosphere and ionosphere responses to them. Model simulations and data analysis were conducted for two flares of similar magnitude (X6.2 and X5.4) that had the same location on the solar limb, but the X6.2 flare had longer rise and decay times. Simulated total electron content (TEC) enhancements from the X6.2 and X5.4 flares were 6 total electron content units (TECU) and approximately 2 TECU, and the simulated neutral density enhancements were approximately 15% -20% and approximately 5%, respectively, in reasonable agreement with observations. Additional model simulations showed that for idealized flares with the same magnitude and location, the thermosphere and ionosphere responses changed significantly as a function of rise and decay rates. The Neupert Effect, which predicts that a faster flare rise rate leads to a larger EUV enhancement during the impulsive phase, caused a larger maximum ion production enhancement. In addition, model simulations showed that increased E x B plasma transport due to conductivity increases during the flares caused a significant equatorial anomaly feature in the electron density enhancement in the F region but a relatively weaker equatorial anomaly feature in TEC enhancement, owing to dominant contributions by photochemical production and loss processes. The latitude dependence of the thermosphere response correlated well with the solar zenith angle effect, whereas the latitude dependence of the ionosphere response was more complex, owing to plasma transport and the winter anomaly.

Effect of Parachute Jump in the Psychophysiological Response of Soldiers in Urban Combat.

PubMed

Sánchez-Molina, Joaquín; Robles-Pérez, José J; Clemente-Suárez, Vicente J

2017-06-01

The study of organic and psychological response during combat situations has been poorly reported despite its importance for soldiers training and specific instruction, so it was proposed as aim of the present investigation to analyze the effect of a tactical parachute simulated jump in psycho-physiological response of paratroopers' warfighters during an urban combat simulation. 19 male paratroopers (31.9 ± 6.2 year old; 173.6 ± 5.3 cm; 73.8 ± 8.3 Kg) of the Spanish Army were divided in two groups: parachute jump group (n:11) that conducted a simulated parachute jump and a urban combat maneuver and a non-parachute jump group (n:8) that only conducted an urban combat maneuver. We analyzed before and after the maneuver the rated perceived exertion, legs strength manifestation, blood lactate, cortical activation, heart rate variability, blood oxygen saturation and pressure, skin temperature, fine motor skills, and anxiety state. A tactical parachute simulated jump prior to an urban combat maneuver produce significantly (p < 0.05) higher heart rate and decrease in specific fine motor skills in comparison with no jump situation in professional Army paratroopers. Independently of the parachute jump, an urban combat maneuver produces a significant increase in rated perceived exertion, blood lactate, heart rate, legs strength, sympathetic modulation and anxiety response as well as a significant decrease in blood oxygen saturation and parasympathetic modulation.

Improvement of cycloid psychosis following electroconvulsive therapy.

PubMed

Holm, Jonas; Brus, Ole; Båve, Ullvi; Landen, Mikael; Lundberg, Johan; Nordanskog, Pia; von Knorring, Lars; Nordenskjöld, Axel

2017-08-01

The treatment of choice for cycloid psychosis has traditionally been electroconvulsive therapy (ECT), but there is a lack of studies on its effectiveness. The primary aim of this register study was to determine the rates of remission and response after ECT for cycloid psychosis. The secondary aim was to examine possible predictors of outcome. Data were obtained from the National Quality Register for ECT in Sweden. The study population was patients (n = 42) who received ECT for acute polymorphic psychotic disorder without symptoms of schizophrenia or for cycloid psychosis between 2011-2015 in 13 hospitals. Remission and response rates were calculated using Clinical Global Impression-Severity (CGI-S) and -Improvement scores, respectively. Variables with possible predictive value were tested using Chi-square and Fisher's exact test. The response rate was 90.5%. The remission rate was 45.2%. Of 42 patients, 40 improved their CGI-S score after ECT (p < 0.001). The mean number of ECT treatments was 2.5 for non-responders and 7.0 for responders (p = 0.010). The mean number of ECT treatments did not differ significantly between remitters and non-remitters (7.2 vs 6.1, p = 0.31). None of the other investigated potential predictors was statistically significantly associated with outcome. ECT is an effective treatment for cycloid psychosis. Future studies need to compare the outcome of ECT to that of other treatment strategies. The high response rate with ECT indicates that cycloid psychosis is a clinically useful diagnosis.

Effects of Response Styles on the Report of Psychological and Somatic Distress.

ERIC Educational Resources Information Center

Linden, Wolfgang; And Others

1986-01-01

Assessed the impact of two major response style dimensions (self-deception and impression management) on the report of psychological and somatic symptoms. Results confirmed that response styles were more predictive of psychological than somatic symptoms. Both anxiety and depression were associated with a high rate of physical symptoms,…

Resistance to Change of Responding Maintained by Unsignaled Delays to Reinforcement: A Response-Bout Analysis

ERIC Educational Resources Information Center

Podlesnik, Christopher A.; Jimenez-Gomez, Corina; Ward, Ryan D.; Shahan, Timothy A.

2006-01-01

Previous experiments have shown that unsignaled delayed reinforcement decreases response rates and resistance to change. However, the effects of different delays to reinforcement on underlying response structure have not been investigated in conjunction with tests of resistance to change. In the present experiment, pigeons responded on a…

Relationship between Biomechanical Characteristics of Spinal Manipulation and Neural Responses in an Animal Model: Effect of Linear Control of Thrust Displacement versus Force, Thrust Amplitude, Thrust Duration, and Thrust Rate

PubMed Central

Reed, William R.; Cao, Dong-Yuan; Long, Cynthia R.; Kawchuk, Gregory N.; Pickar, Joel G.

2013-01-01

High velocity low amplitude spinal manipulation (HVLA-SM) is used frequently to treat musculoskeletal complaints. Little is known about the intervention's biomechanical characteristics that determine its clinical benefit. Using an animal preparation, we determined how neural activity from lumbar muscle spindles during a lumbar HVLA-SM is affected by the type of thrust control and by the thrust's amplitude, duration, and rate. A mechanical device was used to apply a linear increase in thrust displacement or force and to control thrust duration. Under displacement control, neural responses during the HVLA-SM increased in a fashion graded with thrust amplitude. Under force control neural responses were similar regardless of the thrust amplitude. Decreasing thrust durations at all thrust amplitudes except the smallest thrust displacement had an overall significant effect on increasing muscle spindle activity during the HVLA-SMs. Under force control, spindle responses specifically and significantly increased between thrust durations of 75 and 150 ms suggesting the presence of a threshold value. Thrust velocities greater than 20–30 mm/s and thrust rates greater than 300 N/s tended to maximize the spindle responses. This study provides a basis for considering biomechanical characteristics of an HVLA-SM that should be measured and reported in clinical efficacy studies to help define effective clinical dosages. PMID:23401713

Foreign Languages Sound Fast: Evidence from Implicit Rate Normalization.

PubMed

Bosker, Hans Rutger; Reinisch, Eva

2017-01-01

Anecdotal evidence suggests that unfamiliar languages sound faster than one's native language. Empirical evidence for this impression has, so far, come from explicit rate judgments. The aim of the present study was to test whether such perceived rate differences between native and foreign languages (FLs) have effects on implicit speech processing. Our measure of implicit rate perception was "normalization for speech rate": an ambiguous vowel between short /a/ and long /a:/ is interpreted as /a:/ following a fast but as /a/ following a slow carrier sentence. That is, listeners did not judge speech rate itself; instead, they categorized ambiguous vowels whose perception was implicitly affected by the rate of the context. We asked whether a bias towards long /a:/ might be observed when the context is not actually faster but simply spoken in a FL. A fully symmetrical experimental design was used: Dutch and German participants listened to rate matched (fast and slow) sentences in both languages spoken by the same bilingual speaker. Sentences were followed by non-words that contained vowels from an /a-a:/ duration continuum. Results from Experiments 1 and 2 showed a consistent effect of rate normalization for both listener groups. Moreover, for German listeners, across the two experiments, foreign sentences triggered more /a:/ responses than (rate matched) native sentences, suggesting that foreign sentences were indeed perceived as faster. Moreover, this FL effect was modulated by participants' ability to understand the FL: those participants that scored higher on a FL translation task showed less of a FL effect. However, opposite effects were found for the Dutch listeners. For them, their native rather than the FL induced more /a:/ responses. Nevertheless, this reversed effect could be reduced when additional spectral properties of the context were controlled for. Experiment 3, using explicit rate judgments, replicated the effect for German but not Dutch listeners. We therefore conclude that the subjective impression that FLs sound fast may have an effect on implicit speech processing, with implications for how language learners perceive spoken segments in a FL.

In Situ Rates of Sulfate Reduction in Response to Geochemical Perturbations

USGS Publications Warehouse

Kneeshaw, T.A.; McGuire, J.T.; Cozzarelli, I.M.; Smith, E.W.

2011-01-01

Rates of in situ microbial sulfate reduction in response to geochemical perturbations were determined using Native Organism Geochemical Experimentation Enclosures (NOGEEs), a new in situ technique developed to facilitate evaluation of controls on microbial reaction rates. NOGEEs function by first trapping a native microbial community in situ and then subjecting it to geochemical perturbations through the introduction of various test solutions. On three occasions, NOGEEs were used at the Norman Landfill research site in Norman, Oklahoma, to evaluate sulfate-reduction rates in wetland sediments impacted by landfill leachate. The initial experiment, in May 2007, consisted of five introductions of a sulfate test solution over 11 d. Each test stimulated sulfate reduction with rates increasing until an apparent maximum was achieved. Two subsequent experiments, conducted in October 2007 and February 2008, evaluated the effects of concentration on sulfate-reduction rates. Results from these experiments showed that faster sulfate-reduction rates were associated with increased sulfate concentrations. Understanding variability in sulfate-reduction rates in response to perturbations may be an important factor in predicting rates of natural attenuation and bioremediation of contaminants in systems not at biogeochemical equilibrium. Copyright ?? 2011 The Author(s). Journal compilation ?? 2011 National Ground Water Association.

Calcification, Storm Damage and Population Resilience of Tabular Corals under Climate Change

PubMed Central

Madin, Joshua S.; Hughes, Terry P.; Connolly, Sean R.

2012-01-01

Two facets of climate change–increased tropical storm intensity and ocean acidification–are expected to detrimentally affect reef-building organisms by increasing their mortality rates and decreasing their calcification rates. Our current understanding of these effects is largely based on individual organisms’ short-term responses to experimental manipulations. However, predicting the ecologically-relevant effects of climate change requires understanding the long-term demographic implications of these organism-level responses. In this study, we investigate how storm intensity and calcification rate interact to affect population dynamics of the table coral Acropora hyacinthus, a dominant and geographically widespread ecosystem engineer on wave-exposed Indo-Pacific reefs. We develop a mechanistic framework based on the responses of individual-level demographic rates to changes in the physical and chemical environment, using a size-structured population model that enables us to rigorously incorporate uncertainty. We find that table coral populations are vulnerable to future collapse, placing in jeopardy many other reef organisms that are dependent upon them for shelter and food. Resistance to collapse is largely insensitive to predicted changes in storm intensity, but is highly dependent on the extent to which calcification influences both the mechanical properties of reef substrate and the colony-level trade-off between growth rate and skeletal strength. This study provides the first rigorous quantitative accounting of the demographic implications of the effects of ocean acidification and changes in storm intensity, and provides a template for further studies of climate-induced shifts in ecosystems, including coral reefs. PMID:23056379

Probing topology by “heating”: Quantized circular dichroism in ultracold atoms

PubMed Central

Tran, Duc Thanh; Dauphin, Alexandre; Grushin, Adolfo G.; Zoller, Peter; Goldman, Nathan

2017-01-01

We reveal an intriguing manifestation of topology, which appears in the depletion rate of topological states of matter in response to an external drive. This phenomenon is presented by analyzing the response of a generic two-dimensional (2D) Chern insulator subjected to a circular time-periodic perturbation. Because of the system’s chiral nature, the depletion rate is shown to depend on the orientation of the circular shake; taking the difference between the rates obtained from two opposite orientations of the drive, and integrating over a proper drive-frequency range, provides a direct measure of the topological Chern number (ν) of the populated band: This “differential integrated rate” is directly related to the strength of the driving field through the quantized coefficient η0 = ν/ℏ2, where h = 2π ℏ is Planck’s constant. Contrary to the integer quantum Hall effect, this quantized response is found to be nonlinear with respect to the strength of the driving field, and it explicitly involves interband transitions. We investigate the possibility of probing this phenomenon in ultracold gases and highlight the crucial role played by edge states in this effect. We extend our results to 3D lattices, establishing a link between depletion rates and the nonlinear photogalvanic effect predicted for Weyl semimetals. The quantized circular dichroism revealed in this work designates depletion rate measurements as a universal probe for topological order in quantum matter. PMID:28835930

Tertiapin-Q removes a mechanosensitive component of muscarinic control of the sinoatrial pacemaker in the rat.

PubMed

Han, SuYoung; Wilson, Suzanne J; Bolter, Chris P

2010-09-01

1. In an isolated right atrial preparation, an increase in right atrial pressure (RAP) produces an increase in atrial rate. This rate response is larger and occurs faster when there is background vagal or muscarinic stimulation. 2. We hypothesized that in the latter situation, an increase in RAP antagonizes the effect of muscarinic stimulation through stretch inactivation of the mechanosensitive muscarinic potassium current I(K,ACh). 3. In two groups of bath-mounted right atria isolated from male Wistar rats (control n = 12; 300 nmol/L tertiapin-Q treated (to block I(K,ACh)) n = 10), we examined the change in atrial rate when RAP was raised from 2 to 8 mmHg; oxotremorine-M (oxo-M; from 10 to 500 nmol/L) was added to incrementally activate muscarinic receptors. 4. In both control and tertiapin-Q-treated groups, oxo-M reduced atrial rate, but its effect was less ( approximately 40-50%) in the latter group (P < 0.001). In control preparations, responses to an increase in RAP became progressively larger and quicker as the concentration of oxo-M was increased, whereas in tertiapin-Q treated preparations oxo-M did not affect either the amplitude or the speed of the response (P < 0.0001 for both). 5. The results support the hypothesis that atrial stretch antagonizes muscarinic slowing by its effect on I(K,ACh). We suggest that through this mechanism, parasympathetic control of heart rate may be modulated continuously by RAP.

Phototropin 1 and dim-blue light modulate the red light de-etiolation response.

PubMed

Wang, Yihai; M Folta, Kevin

2014-01-01

Light signals regulate seedling morphological changes during de-etiolation through the coordinated actions of multiple light-sensing pathways. Previously we have shown that red-light-induced hypocotyl growth inhibition can be reversed by addition of dim blue light through the action of phototropin 1 (phot1). Here we further examine the fluence-rate relationships of this blue light effect in short-term (hours) and long-term (days) hypocotyl growth assays. The red stem-growth inhibition and blue promotion is a low-fluence rate response, and blue light delays or attenuates both the red light and far-red light responses. These de-etiolation responses include blue light reversal of red or far-red induced apical hook opening. This response also requires phot1. Cryptochromes (cry1 and cry2) are activated by higher blue light fluence-rates and override phot1's influence on hypocotyl growth promotion. Exogenous application of auxin transport inhibitor naphthylphthalamic acid abolished the blue light stem growth promotion in both hypocotyl growth and hook opening. Results from the genetic tests of this blue light effect in auxin transporter mutants, as well as phytochrome kinase substrate mutants indicated that aux1 may play a role in blue light reversal of red light response. Together, the phot1-mediated adjustment of phytochrome-regulated photomorphogenic events is most robust in dim blue light conditions and is likely modulated by auxin transport through its transporters.

The evolutionary and behavioral modification of consumer responses to environmental change.

PubMed

Abrams, Peter A

2014-02-21

How will evolution or other forms of adaptive change alter the response of a consumer species' population density to environmentally driven changes in population growth parameters? This question is addressed by analyzing some simple consumer-resource models to separate the ecological and evolutionary components of the population's response. Ecological responses are always decreased population size, but evolution of traits that have effects on both resource uptake rate and another fitness-related parameter may magnify, offset, or reverse this population decrease. Evolution can change ecologically driven decreases in population size to increases; this is likely when: (1) resources are initially below the density that maximizes resource growth, and (2) the evolutionary response decreases the consumer's resource uptake rate. Evolutionary magnification of the ecological decreases in population size can occur when the environmental change is higher trait-independent mortality. Such evolution-driven decreases are most likely when uptake-rate traits increase and the resource is initially below its maximum growth density. It is common for the difference between the new eco-evolutionary equilibrium and the new ecological equilibrium to be larger than that between the original and new ecological equilibrium densities. The relative magnitudes of ecological and evolutionary effects often depend sensitively on the magnitude of the environmental change and the nature of resource growth. © 2013 Elsevier Ltd. All rights reserved.

Evaluating Active Parental Consent Procedures for School Programming: Addressing the Sensitive Topic of Suicide Prevention.

PubMed

Totura, Christine M Wienke; Kutash, Krista; Labouliere, Christa D; Karver, Marc S

2017-02-01

Suicide is the second leading cause of death for adolescents. Whereas school-based prevention programs are effective, obtaining active consent for youth participation in public health programming concerning sensitive topics is challenging. We explored several active consent procedures for improving participation rates. Five active consent methods (in-person, students taking forms home, mailing, mailing preceded by primers, mailing followed by reminder calls) were compared against passive consent procedures to evaluate recruitment success, as determined by participation (proportion who responded yes) and response (proportion who returned any response) rates. Participation acceptance rates ranged from 38 to 100% depending on consent method implemented. Compared with passive consent, active consent procedures were more variable in response and participation rates. In-person methods provided higher rates than less interpersonal methods, such as mailing or students taking consents home. Mailed primers before or reminder calls after consent forms were mailed increased response but not participation rates. Students taking consents home resulted in the lowest rates. Although passive consent produces the highest student participation, these methods are not always appropriate for programs addressing sensitive topics in schools. In-person active consent procedures may be the best option when prioritizing balance between parental awareness and successful student recruitment. © 2017, American School Health Association.

Efficacy of Skin-Directed Therapy for Cutaneous Metastases From Advanced Cancer: A Meta-Analysis

PubMed Central

Spratt, Daniel E.; Gordon Spratt, Elizabeth A.; Wu, Shenhong; DeRosa, Antonio; Lee, Nancy Y.; Lacouture, Mario E.; Barker, Christopher A.

2014-01-01

Purpose To perform the first meta-analysis of the efficacy of skin-directed therapies for cutaneous metastases. Methods MEDLINE, EMBASE, The Cochrane Library, and ClinicalTrials.gov databases were searched for reports of prospective clinical studies published between 1960 and 2013 that assessed the response of skin-directed therapy for cutaneous metastases (47 of 2,955 unique studies were selected). Primary end points of the study were complete and objective response rates. Secondary analyses were preplanned and included subgroup analyses by skin-directed therapy, histology, and recurrence rates. Meta-analyses were performed with random-effect modeling, and extent of heterogeneity between studies was determined with the Cochran Q and I2 tests. Results After applying exclusion criteria, 47 prospective studies of 4,313 cutaneous metastases were assessed. Five skin-directed therapies were identified: electrochemotherapy, photodynamic therapy, radiotherapy, intralesional therapy, and topical therapy. Among all cutaneous metastases, complete response rate was 35.5% (95% CI, 27.6% to 44.3%) and objective response rate was 60.2% (95% CI, 50.6% to 69.0%). Overall recurrence rate was estimated to be 9.2% (95% CI, 3.7% to 21.2%). Melanoma and breast carcinoma comprised 96.8% of all cutaneous metastases studied and had similar objective response rates (54.5% [95% CI, 48.3% to 60.7%] and 54.0% [95% CI, 48.3% to 59.7%], respectively). Grade ≥ 3 toxicity was reported in less than 6% of patients. Conclusion Response to skin-directed therapy for cutaneous metastases is high but heterogeneous across treatment modalities, with low rates of recurrence post-treatment. Treatment was generally well tolerated and conferred improvements in quality of life. Standardization of response criteria for cutaneous metastases and treatment algorithms to optimally use the available skin-directed therapies are needed. PMID:25154827

75 FR 51504 - Changes in Postal Rates

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-20

... INFORMATION CONTACT: Stephen L. Sharfman, General Counsel, [email protected] or 202-789-6820... rates took effect on January 1, 2009. In Order No. 281, the Commission accepted the change in rates not... Expedited Services 2, August 19, 2009 (Order No. 281). \\4\\ See Docket No. CP2009-57, Response of the United...

Effects of gastric distension and infusion of umami and bitter taste stimuli on vagal afferent activity.

PubMed

Horn, Charles C; Murat, Chloé; Rosazza, Matthew; Still, Liz

2011-10-24

Until recently, sensory nerve pathways from the stomach to the brain were thought to detect distension and play little role in nutritional signaling. Newer data have challenged this view, including reports on the presence of taste receptors in the gastrointestinal lumen and the stimulation of multi-unit vagal afferent activity by glutamate infusions into the stomach. However, assessing these chemosensory effects is difficult because gastric infusions typically evoke a distension-related vagal afferent response. In the current study, we recorded gastric vagal afferent activity in the rat to investigate the possibility that umami (glutamate, 150 mM) and bitter (denatonium, 10 mM) responses could be dissociated from distension responses by adjusting the infusion rate and opening or closing the drainage port in the stomach. Slow infusions of saline (5 ml over 2 min, open port) produced no significant effects on vagal activity. Using the same infusion rate, glutamate or denatonium solutions produced little or no effects on vagal afferent activity. In an attempt to reproduce a prior report that showed distention and glutamate responses, we produced a distension response by closing the exit port. Under this condition, response to the infusion of glutamate or denatonium was similar to saline. In summary, we found little or no effect of gastric infusion of glutamate or denatonium on gastric vagal afferent activity that could be distinguished from distension responses. The current results suggest that sensitivity to umami or bitter stimuli is not a common property of gastric vagal afferent fibers. Copyright © 2011 Elsevier B.V. All rights reserved.

Results of the randomized phase IIB ARCTIC trial of low-dose rituximab in previously untreated CLL.

PubMed

Howard, D R; Munir, T; McParland, L; Rawstron, A C; Milligan, D; Schuh, A; Hockaday, A; Allsup, D J; Marshall, S; Duncombe, A S; O'Dwyer, J L; Smith, A F; Longo, R; Varghese, A; Hillmen, P

2017-11-01

ARCTIC was a multicenter, randomized-controlled, open, phase IIB non-inferiority trial in previously untreated chronic lymphocytic leukemia (CLL). Conventional frontline therapy in fit patients is fludarabine, cyclophosphamide and rituximab (FCR). The trial hypothesized that including mitoxantrone with low-dose rituximab (FCM-miniR) would be non-inferior to FCR. A total of 200 patients were recruited to assess the primary end point of complete remission (CR) rates according to IWCLL criteria. Secondary end points were progression-free survival (PFS), overall survival (OS), overall response rate, minimal residual disease (MRD) negativity, safety and cost-effectiveness. The trial closed following a pre-planned interim analysis. At final analysis, CR rates were 76 FCR vs 55% FCM-miniR (adjusted odds ratio: 0.37; 95% confidence interval: 0.19-0.73). MRD-negativity rates were 54 FCR vs 44% FCM-miniR. More participants experienced serious adverse reactions with FCM-miniR (49%) compared to FCR (41%). There are no significant differences between the treatment groups for PFS and OS. FCM-miniR is not expected to be cost-effective over a lifetime horizon. In summary, FCM-miniR is less well tolerated than FCR with an inferior response and MRD-negativity rate and increased toxicity, and will not be taken forward into a confirmatory trial. The trial demonstrated that oral FCR yields high response rates compared to historical series with intravenous chemotherapy.

On Suggestibility and Placebo: A Follow-Up Study.

PubMed

Lifshitz, Michael; Sheiner, Eli O; Olson, Jay A; Thériault, Rémi; Raz, Amir

2017-04-01

Identifying what makes some people respond well to placebos remains a major challenge. Here, we attempt to replicate an earlier study in which we found a relationship between hypnotic suggestibility and subjective ratings of relaxation following the ingestion of a placebo sedative (Sheiner, Lifshitz, & Raz, 2016). To assess the reliability of this effect, we tested 34 participants using a similar design. Participants ingested a placebo capsule in one of two conditions: (1) relaxation, wherein we described the capsule as a herbal sedative, or (2) control, wherein we described the capsule as inert. To index placebo response, we collected measures of blood pressure and heart rate, as well as self-report ratings of relaxation and drowsiness. Despite using a similar experimental design as in our earlier study, we were unable to replicate the correlation between hypnotic suggestibility and placebo response. Furthermore, whereas in our former experiment we observed a change in subjective ratings of relaxation but no change in physiological measures, here we found that heart rate dropped in the relaxation condition while subjective ratings remained unchanged. Even within a consistent context of relaxation, therefore, our present results indicate that placebos may induce effects that are fickle, tenuous, and unreliable. Although we had low statistical power, our findings tentatively accord with the notion that placebo response likely involves a complex, multifaceted interaction between traits, expectancies, and contexts.

A methodology for enhancing implementation science proposals: comparison of face-to-face versus virtual workshops.

PubMed

Marriott, Brigid R; Rodriguez, Allison L; Landes, Sara J; Lewis, Cara C; Comtois, Katherine A

2016-05-06

With the current funding climate and need for advancements in implementation science, there is a growing demand for grantsmanship workshops to increase the quality and rigor of proposals. A group-based implementation science-focused grantsmanship workshop, the Implementation Development Workshop (IDW), is one methodology to address this need. This manuscript provides an overview of the IDW structure, format, and findings regarding its utility. The IDW methodology allows researchers to vet projects in the proposal stage in a structured format with a facilitator and two types of expert participants: presenters and attendees. The presenter uses a one-page handout and verbal presentation to present their proposal and questions. The facilitator elicits feedback from attendees using a format designed to maximize the number of unique points made. After each IDW, participants completed an anonymous survey assessing perceptions of the IDW. Presenters completed a funding survey measuring grant submission and funding success. Qualitative interviews were conducted with a subset of participants who participated in both delivery formats. Mixed method analyses were performed to evaluate the effectiveness and acceptability of the IDW and compare the delivery formats. Of those who participated in an IDW (N = 72), 40 participated in face-to-face only, 16 in virtual only, and 16 in both formats. Thirty-eight (face-to-face n = 12, 35 % response rate; virtual n = 26, 66.7 % response rate) responded to the surveys and seven (15.3 % response rate), who had attended both formats, completed an interview. Of 36 total presenters, 17 (face-to-face n = 12, 42.9 % response rate; virtual n = 5, 62.9 % response rate) responded to the funding survey. Mixed method analyses indicated that the IDW was effective for collaboration and growth, effective for enhancing success in obtaining grants, and acceptable. A third (35.3 %) of presenters ultimately received funding for their proposal, and more than 80 % of those who presented indicated they would present again in the future. The IDW structure and facilitation process were found to be acceptable, with both formats rated as equally strong. The IDW presents an acceptable and successful methodology for increasing competitiveness of implementation science grant proposals.

Stability of landsat-4 thematic mapper outgassing models

USGS Publications Warehouse

Micijevic, E.; Chander, G.

2006-01-01

Oscillations in radiometric gains of the short wave infrared (SWIR) bands in Landsat-4 (L4) and Landsat-5 (L5) Thematic Mappers (TMs) are observed through an analysis of detector responses to the Internal Calibrator (IC) pulses. The oscillations are believed to be caused by an interference effect due to a contaminant film buildup on the window of the cryogenically cooled dewar that houses these detectors. This process of contamination, referred to as outgassing effects, has been well characterized using an optical thin-film model that relates detector responses to the accumulated film thickness and its growth rate. The current models for L4 TM are based on average detector responses to the second brightest IC lamp and have been derived from three data sets acquired during different times throughout the instrument's lifetime. Unlike in L5 TM outgassing characterization, it was found that the L4 TM responses to all three IC lamps can be used to provide accurate characterization and correction for outgassing effects. The analysis of single detector responses revealed an up to five percent difference in the estimated oscillating periods and also indicated a gradual variation of contaminant growth rate over the focal plane.

The effects of d-lysergic acid diethylamide (LSD), 2,5-dimethoxy-4-methylamphetamine (DOM) and d-amphetamine on operant responding in control and 6-hydroxydopamine-treated rats.

PubMed

Commissaris, R; Lyness, W H; Cordon, J J; Moore, K E; Rech, R H

1980-11-01

The purpose of the present study was to determine the role of central catecholaminergic neuronal systems in the effects of LSD, DOM and d-amphetamine on fixed ratio (FR) operant responding in rats. Food-deprived male rats were trained to press a bar for food reinforcement on a FR-40 schedule. Control responding on this schedule is characterized by a rapid, constant rate of responding (approximately 100 responses/min) throughout a 40 min test session. LSD and DOM, as with other hallucinogens, produced dose-dependent periods of nonresponding or "pausing," followed by reinstatement of responding at or near the control rate. Administration of the non-hallucinogen, d-amphetamine, did not produce "pausing," but caused the response rate to slow and become erratic. In animals pretreated intraventricularly with 6-hydroxydopamine (6-OHDA; 200 micrograms/10 microliter X 2), the response to LSD and DOM was unchanged, while the response to d-amphetamine was significantly diminished. The neurotoxin significantly decreased brain catecholamines to less than 25 percent of control in al regions examined, without altering 5-HT concentrations in these same regions. These data demonstrate that the effects of LSD and DOM on FR-40 responding are quite different from those of d-amphetamine, and that this difference may be due to the extent of catecholamine involvement in the effects of these agents.

Soil nutrient additions increase invertebrate herbivore abundances, but not herbivory, across three grassland systems.

PubMed

La Pierre, Kimberly J; Smith, Melinda D

2016-02-01

Resource availability may influence invertebrate communities, with important consequences for ecosystem function, such as biomass production. We assessed: (1) the effects of experimental soil nutrient additions on invertebrate abundances and feeding rates and (2) the resultant changes in the effects of invertebrates on aboveground plant biomass at three grassland sites spanning the North American Central Plains, across which plant tissue chemistry and biomass vary. Invertebrate communities and rates of herbivory were sampled within a long-term nutrient-addition experiment established at each site along the broad Central Plains precipitation gradient. Additionally, the effects of invertebrates on aboveground plant biomass were determined under ambient and elevated nutrient conditions. At the more mesic sites, invertebrate herbivore abundances increased and their per capita rate of herbivory decreased with nutrient additions. In contrast, at the semi-arid site where plant biomass is low and plant nutrient concentrations are high, invertebrate herbivore abundances did not vary and per capita rates of herbivory increased with nutrient additions. No change in the effect of invertebrate herbivores on aboveground plant biomass was observed at any of the sites. In sum, nutrient additions induced shifts in both plant biomass and leaf nutrient content, which altered invertebrate abundances and feeding rate. However, due to the inverse relationship between changes in herbivore abundance and per capita rates of herbivory, nutrient additions did not alter the effect of invertebrates on aboveground biomass. Overall, we suggest that this inverse response of herbivore abundance and per capita feeding rate may buffer ecosystems against changes in invertebrate damage in response to fluctuations in nutrient levels.

Glutamate Excitoxicity Is the Key Molecular Mechanism Which Is Influenced by Body Temperature during the Acute Phase of Brain Stroke

PubMed Central

Campos, Francisco; Pérez-Mato, María; Agulla, Jesús; Blanco, Miguel; Barral, David; Almeida, Ángeles; Brea, David; Waeber, Christian; Castillo, José; Ramos-Cabrer, Pedro

2012-01-01

Glutamate excitotoxicity, metabolic rate and inflammatory response have been associated to the deleterious effects of temperature during the acute phase of stroke. So far, the association of temperature with these mechanisms has been studied individually. However, the simultaneous study of the influence of temperature on these mechanisms is necessary to clarify their contributions to temperature-mediated ischemic damage. We used non-invasive Magnetic Resonance Spectroscopy to simultaneously measure temperature, glutamate excitotoxicity and metabolic rate in the brain in animal models of ischemia. The immune response to ischemia was measured through molecular serum markers in peripheral blood. We submitted groups of animals to different experimental conditions (hypothermia at 33°C, normothermia at 37°C and hyperthermia at 39°C), and combined these conditions with pharmacological modulation of glutamate levels in the brain through systemic injections of glutamate and oxaloacetate. We show that pharmacological modulation of glutamate levels can neutralize the deleterious effects of hyperthermia and the beneficial effects of hypothermia, however the analysis of the inflammatory response and metabolic rate, demonstrated that their effects on ischemic damage are less critical than glutamate excitotoxity. We conclude that glutamate excitotoxicity is the key molecular mechanism which is influenced by body temperature during the acute phase of brain stroke. PMID:22952923

Glutamate excitoxicity is the key molecular mechanism which is influenced by body temperature during the acute phase of brain stroke.

PubMed

Campos, Francisco; Pérez-Mato, María; Agulla, Jesús; Blanco, Miguel; Barral, David; Almeida, Angeles; Brea, David; Waeber, Christian; Castillo, José; Ramos-Cabrer, Pedro

2012-01-01

Glutamate excitotoxicity, metabolic rate and inflammatory response have been associated to the deleterious effects of temperature during the acute phase of stroke. So far, the association of temperature with these mechanisms has been studied individually. However, the simultaneous study of the influence of temperature on these mechanisms is necessary to clarify their contributions to temperature-mediated ischemic damage. We used non-invasive Magnetic Resonance Spectroscopy to simultaneously measure temperature, glutamate excitotoxicity and metabolic rate in the brain in animal models of ischemia. The immune response to ischemia was measured through molecular serum markers in peripheral blood. We submitted groups of animals to different experimental conditions (hypothermia at 33°C, normothermia at 37°C and hyperthermia at 39°C), and combined these conditions with pharmacological modulation of glutamate levels in the brain through systemic injections of glutamate and oxaloacetate. We show that pharmacological modulation of glutamate levels can neutralize the deleterious effects of hyperthermia and the beneficial effects of hypothermia, however the analysis of the inflammatory response and metabolic rate, demonstrated that their effects on ischemic damage are less critical than glutamate excitotoxity. We conclude that glutamate excitotoxicity is the key molecular mechanism which is influenced by body temperature during the acute phase of brain stroke.

Disinhibition by propranolol and chlordiazepoxide of nonrewarded lever-pressing in the rat is unaffected by dorsal noradrenergic bundle lesion.

PubMed

Salmon, P; Tsaltas, E; Gray, J A

1989-03-01

Ten male Sprague-Dawley rats received 6-hydroxydopamine-induced lesions of the dorsal noradrenergic bundle and 10 others underwent control operations. The lesion depleted levels of noradrenaline in the hippocampus to 2% of those in the controls. All rats were then trained for 16 sessions to lever-press in a Skinner box on a variable interval 18 sec schedule of food-reinforcement, then for 42 days on a successive discrimination between periods of variable interval (VI 18 sec) food-reinforcement and periods of extinction. This report describes the effects of chlordiazepoxide (CDP; 5 mg/kg) and propranolol (5 and 10 mg/kg) injected intraperitoneally in both groups on modified ABBA designs after this training. Both drugs increased the response rates in extinction periods. The effect of propranolol was similar at each dose and smaller than that of CDP. Although CDP and propranolol (5 mg/kg) increased variable interval response rates also, this could not account for the effect on extinction response rates. Responding did not differ between the lesioned and control animals and the effects of drugs were similar in each group. It is unlikely that CDP or propranolol release nonrewarded responding by disrupting transmission in the dorsal noradrenergic bundle.

Randomized, double-blind, placebo-controlled trial of fluoxetine treatment for elderly patients with dysthymic disorder.

PubMed

Devanand, D P; Nobler, Mitchell S; Cheng, Jocelyn; Turret, Nancy; Pelton, Gregory H; Roose, Steven P; Sackeim, Harold A

2005-01-01

The authors compared the efficacy and side effects of fluoxetine and placebo in elderly outpatients with dysthymic disorder. Patients were randomly assigned to fluoxetine (20 mg-60 mg/day) or placebo for 12 weeks in a double-blind trial. Of 90 randomized patients, 71 completed the trial. In the intent-to-treat sample, random regression analyses of the Hamilton Rating Scale for Depression (Ham-D; 24-item) and Cornell Dysthymia Rating Scale (CDRS) scores at each visit produced significant time x treatment group interactions favoring the fluoxetine group. Analysis of percentage change in Ham-D scores yielded no effect for treatment group, but a similar analysis of percentage change in CDRS scores yielded a main effect for treatment group, favoring fluoxetine over placebo. In the intent-to-treat sample, response rates were 27.3% for fluoxetine and 19.6% for placebo. In the completer sample, response rates were 37.5% for fluoxetine and 23.1% for placebo. Fluoxetine had limited efficacy in elderly dysthymic patients. The clinical features of elderly dysthymic patients are typically distinct from those of dysthymic disorder in young adults, and the findings suggest that treatments effective for young adult dysthymic patients may not be as useful in elderly dysthymic patients. Further research is needed to identify efficacious treatments for elderly patients with dysthymic disorder, and investigative tools such as electronic/computerized brain scans and neuropsychological testing may help identify the factors that moderate antidepressant treatment response and resistance.

The Effects of Chlordiazepoxide and d-Amphetamine during a Three-Component Multiple Schedule

PubMed Central

Romanowich, Paul; Lamb, R. J.

2013-01-01

Multiple schedules have been used in behavioral pharmacology research to show that a drug’s effect on behavior can be a function of the schedule of reinforcement that supports that behavior. However, less research has examined whether the context of the schedule of reinforcement in a multiple schedule can change the drug’s effect on behavior. We examined the effects of acute chlordiazepoxide and d-amphetamine injections on the behavior of two groups of pigeons trained on a three-component multiple schedule with identical schedules of reinforcement in the first and last components. For one group of pigeons reinforcement was unavailable during the middle component (decreased-middle-component). For the second group reinforcement rate was higher during the middle component than during the first or third components (increased-middle-component). In the decreased-middle-component group, chlordiazepoxide (3.2-32 mg/kg) decreased third-component response rates less than it decreased responding in the first component. Conversely, in the increased-middle-component group, chlordiazepoxide (3.2-10 mg/kg) decreased third-component response rates more than in the first component. In both groups, d-amphetamine did not differentially affect response rates across components. These results are consistent with previous research showing that drugs can differentially affect responding to two different schedules of reinforcement during the same session, and suggest that pharmacological preparations may be helpful in elucidating the mechanisms that control multiple schedule interactions. PMID:23633164

Seed germination in response to chemicals: effect of nitrogen and pH in the media.

PubMed

Pérez-Fernández, M A; Calvo-Magro, E; Montanero-Fernández, J; Oyola-Velasco, J A

2006-01-01

Seed germination generally presents a peak in the next growing season after a fire. Among other factors associated with fire are the increase of soil nitrogen and changes in the pH of the soil. In this study, we addressed the question, whether or not the germination response of eight species is linked with the increase in pH and nitrogenous compounds in the germination media? We assessed the separate and combined effects of nitrogenous compounds and pH on the percentage and rate of germination of seeds of Medicago arabica (L.) Hudson, Epilobium hirsutum L., Foeniculum vulgare Miller, Daucus carota L., Thapsia villosa L., Cynosurus cristatus L., Dactylis glomerata L. and Rumex crispus L. All these species are well represented in the Mediterranean ecosystems of the central-west Spain. Water and CaCl2 were used as controls. Nitrogenous compounds increased percent germination (level) and rate in three of the species studied. High pH negatively affected the germination rate of seeds from most species, but had no effect on the per cent germination of any of the species. The higher concentration of the nutritious solutions affected negatively the germination level and rate. The different germination responses of seeds of the studied species could not be exclusively attributed to pH values in the media, whereas the amount and form of Nitrogen in the media has a greater effect on it. These differences in germination are species dependent.

Age-Related Effects on Memory for Social Stimuli: The Role of Valence, Arousal, and Emotional Responses

PubMed Central

Hess, Thomas M.; Popham, Lauren E.; Growney, Claire M.

2017-01-01

Background Previous research (Hess, Popham, Dennis, & Emery, 2013) suggested that age-based positivity effects in memory were attenuated with social stimuli. We examined the degree to which this generalized across arousal levels associated with social images. We also examined variations in approach and avoidance responses to images, and how these were differentially related to memory in younger versus older adults. Methods In Experiment 1, young (22 – 43 years) and older (65 – 85 years) adults recalled positive and negative social scenes that were high or low in arousal. In Experiment 2, young (20 – 40 years) and older (65 – 83 years) adults viewed and recalled the same scenes under instructions designed to alter arousal, and approach and avoidance ratings for each image were recorded. Results In Experiment 1, age differences in recall were confined to high-arousal, negative images, with young adults exhibiting superior memory relative to older adults. There was no evidence of an age-related positivity effect for low arousal social scenes. This result was replicated in Experiment 2, but distancing instructions minimized the age difference in recall for high-arousal, negative images. Approach and avoidance ratings differentially predicted recall across age groups, with stronger associations in the young. Conclusion The results are consistent with emerging evidence demonstrating that valence-based biases associated with aging (e.g., positivity effect) are specific to the context and stimulus characteristics. Differences in prediction of recall responses from approach and avoidance ratings across age groups suggested that the observed effects in memory reflected differences in responses to the characteristics of stimuli. PMID:28230420

Evaluation of the effects of the metals Cd, Cr, Pb and their mixture on the filtration and oxygen consumption rates in catarina scallop, Argopecten ventricosus juveniles.

PubMed

Sobrino-Figueroa, Alma S; Cáceres-Martinez, Carlos

2014-01-01

In this work, we evaluated the effect of sublethal concentrations ( LC25, LC10 and LC5) of cadmium, chromium, lead, and their mixture on the filtration rate and oxygen consumption rate of Catarina scallop, Argopecten ventricosus (Sowerby, 1842), juveniles, in order to evaluate the use of these biomarkers as a reliable tool in environmental monitoring studies, because these metals have been found at high levels in water and sediments in the Mexican Pacific systems. An inverse dose-response relationship was observed when metal concentration and exposure time increased, the filtration rate and oxygen consumption rate reduced. The physiological responses evaluated in this study were sufficiently sensitive to detect alterations in the organisms at 0.014 mg l(-1) Cd, 0.311 mg l(-1) Cr, 0.125 mg l(-1) Pb and 0.05 mg l(-1) Cd + Cr + Pb at 24 and 72 hrs. Cd showed the most drastic effect. The Catarina scallop juveniles were more sensitive to Cd, Cr and Pb as compared to other bivalves. The biomarkers evaluated are a reliable tool to carry out environmental monitoring studies.

A cell impedance measurement device for the cytotoxicity assay dependent on the velocity of supplied toxic fluid

NASA Astrophysics Data System (ADS)

Kang, Yoon-Tae; Kim, Min-Ji; Cho, Young-Ho

2018-04-01

We present a cell impedance measurement chip capable of characterizing the toxic response of cells depending on the velocity of the supplied toxic fluid. Previous impedance-based devices using a single open-top chamber have been limited to maintaining a constant supply velocity, and devices with a single closed-top chamber present difficulties in simultaneous cytotoxicity assay for varying levels of supply velocities. The present device, capable of generating constant and multiple levels of toxic fluid velocity simultaneously within a single stepwise microchannel, performs a cytotoxicity assay dependent on toxic fluid velocity, in order to find the effective velocity of toxic fluid to cells for maximizing the cytotoxic effect. We analyze the cellular toxic response of 5% ethanol media supplied to cancer cells within a toxic fluid velocity range of 0-8.3 mm s-1. We observe the velocity-dependent cell detachment rate, impedance, and death rate. We find that the cell detachment rate decreased suddenly to 2.4% at a velocity of 4.4 mm s-1, and that the change rates of cell resistance and cell capacitance showed steep decreases to 8% and 41%, respectively, at a velocity of 5.7 mm s-1. The cell death rate and impedance fell steeply to 32% at a velocity of 5.7 mm s-1. We conclude that: (1) the present device is useful in deciding on the toxic fluid velocity effective to cytotoxicity assay, since the cellular toxic response is dependent on the velocity of toxic fluid, and; (2) the cell impedance analysis facilitates a finer cellular response analysis, showing better correlation with the cell death rate, compared to conventional visual observation. The present device, capable of performing the combinational analysis of toxic fluid velocity and cell impedance, has potential for application to the fine cellular toxicity assay of drugs with proper toxic fluid velocity.

Vascular dilation, tachycardia, and increased inotropy occur sequentially with increasing epinephrine dose rate, plasma and myocardial concentrations, and cAMP

PubMed Central

Maslov, Mikhail Y.; Wei, Abraham E.; Pezone, Matthew J.; Edelman, Elazer R.; Lovich, Mark A.

2015-01-01

Background While epinephrine infusion is widely used in critical care for inotropic support, there is no direct method to detect the onset and measure the magnitude of this response. We hypothesized that surrogate measurements, such as heart rate and vascular tone, may indicate if the plasma and tissue concentrations of epinephrine and cAMP are in a range sufficient to increase myocardial contractility. Methods Cardiovascular responses to epinephrine infusion (0.05–0.5 mcg·kg−1·min−1) were measured in rats using arterial and left ventricular catheters. Epinephrine and cAMP levels were measured using ELISA techniques. Results The lowest dose of epinephrine infusion (0.05 mcg·kg−1·min−1) did not raise plasma epinephrine level and did not lead to cardiovascular response. Incremental increase in epinephrine infusion (0.1 mcg·kg−1·min−1) elevated plasma but not myocardial epinephrine levels, providing vascular, but not cardiac effects. Further increase in the infusion rate (0.2 mcg·kg−1·min−1) raised myocardial tissue epinephrine levels sufficient to increase heart rate but not contractility. Inotropic and lusitropic effects were significant at the infusion rate of 0.3 mcg·kg−1·min−1. Correlation of plasma epinephrine to hemodynamic parameters suggest that as plasma concentration increases, systemic vascular resistance falls (EC50=47 pg/ml), then HR increases (ED50=168 pg/ml), followed by a rise in contractility and lusitropy (ED50=346 pg/ml and ED50=324 pg/ml accordingly). Conclusions The dose response of epinephrine is distinct for vascular tone, HR and contractility. The need for higher doses to see cardiac effects is likely due to the threshold for drug accumulation in tissue. Successful inotropic support with epinephrine cannot be achieved unless the infusion is sufficient to raise the heart rate. PMID:25790776

Optimizing patient-reported outcome and risk factor reporting from cancer survivors: a randomized trial of four different survey methods among colorectal cancer survivors.

PubMed

Feigelson, Heather Spencer; McMullen, Carmit K; Madrid, Sarah; Sterrett, Andrew T; Powers, J David; Blum-Barnett, Erica; Pawloski, Pamala A; Ziegenfuss, Jeanette Y; Quinn, Virginia P; Arterburn, David E; Corley, Douglas A

2017-06-01

The goal of this study was to determine response rates and associated costs of different survey methods among colorectal cancer (CRC) survivors. We assembled a cohort of 16,212 individuals diagnosed with CRC (2010-2014) from six health plans, and randomly selected 4000 survivors to test survey response rates across four mixed-mode survey administration protocols (in English and Spanish): arm 1, mailed survey with phone follow-up; arm 2, interactive voice response (IVR) followed by mail; arm 3; email linked to web-based survey with mail follow-up; and arm 4, email linked to web-based survey followed by IVR. Our overall response rate was 50.2%. Arm 1 had the highest response rate (59.9%), followed by arm 3 (51.9%), arm 2 (51.2%), and arm 4 (37.9%). Response rates were higher among non-Hispanic whites in all arms than other racial/ethnic groups (p < 0.001), among English (51.5%) than Spanish speakers (36.4%) (p < 0.001), and among higher (53.7%) than lower (41.4%) socioeconomic status (p < 0.001). Survey arms were roughly comparable in cost, with a difference of only 8% of total costs between the most (arm 2) and least (arm 3) expensive arms. Mailed surveys followed by phone calls achieved the highest response rate; email invitations and online surveys cost less per response. Electronic methods, even among those with email availability, may miss important populations including Hispanics, non-English speakers, and those of lower socioeconomic status. Our results demonstrate effective methods for capturing patient-reported outcomes, inform the relative benefits/disadvantages of the different methods, and identify future research directions.

Utility and Cost-Effectiveness of Motivational Messaging to Increase Survey Response in Physicians: A Randomized Controlled Trial

ERIC Educational Resources Information Center

Chan, Randolph C. H.; Mak, Winnie W. S.; Pang, Ingrid H. Y.; Wong, Samuel Y. S.; Tang, Wai Kwong; Lau, Joseph T. F.; Woo, Jean; Lee, Diana T. F.; Cheung, Fanny M.

2018-01-01

The present study examined whether, when, and how motivational messaging can boost the response rate of postal surveys for physicians based on Higgin's regulatory focus theory, accounting for its cost-effectiveness. A three-arm, blinded, randomized controlled design was used. A total of 3,270 doctors were randomly selected from the registration…

Fertilizer responses of longleaf pine trees within a loblolly pine plantation: separating direct effects from competition effects

Treesearch

Peter H Anderson; Kurt H. Johnsen

2009-01-01

Evidence is mixed on how well longleaf pine (Pinus palustris Mill.) responds to increased soil nitrogen via fertilization. We examined growth and physiological responses of volunteer longleaf pine trees within an intensive loblolly pine (Pinus taeda L.) fertilization experiment. Fertilizer was applied annually following thinning at age 8 years (late 1992) at rates...

Exposure to Sexist Humor and Rape Proclivity: The Moderator Effect of Aversiveness Ratings

ERIC Educational Resources Information Center

Romero-Sanchez, Monica; Duran, Mercedes; Carretero-Dios, Hugo; Megias, Jesus L.; Moya, Miguel

2010-01-01

The aim of this study is to explore the effect of exposure to sexist humor about women on men's self-reported rape proclivity. Earlier studies have shown that exposure to this type of humor increases rape proclivity and that funniness responses to jokes are a key element to consider. However, the role of aversiveness responses has not been…

Perceptions of Missouri High School Principals Regarding the Effectiveness of In-School Suspension as a Disciplinary Procedure.

ERIC Educational Resources Information Center

Billings, Ward H.; Enger, John M.

This paper presents findings of a study that examined Missouri high school principals' perceptions of the effectiveness of various disciplinary procedures, with a focus on in-school suspension (ISS). A survey mailed to 200 Missouri high school principals elicited 159 responses, a 77 percent response rate. The questionnaire asked principals to…

Linear response theory for annealing of radiation damage in semiconductor devices

NASA Technical Reports Server (NTRS)

Litovchenko, Vitaly

1988-01-01

A theoretical study of the radiation/annealing response of MOS ICs is described. Although many experiments have been performed in this field, no comprehensive theory dealing with radiation/annealing response has been proposed. Many attempts have been made to apply linear response theory, but no theoretical foundation has been presented. The linear response theory outlined here is capable of describing a broad area of radiation/annealing response phenomena in MOS ICs, in particular, both simultaneous irradiation and annealing, as well as short- and long-term annealing, including the case when annealing is nearing completion. For the first time, a simple procedure is devised to determine the response function from experimental radiation/annealing data. In addition, this procedure enables us to study the effect of variable temperature and dose rate, effects which are of interest in spaceflight. In the past, the shift in threshold potential due to radiation/annealing has usually been assumed to depend on one variable: the time lapse between an impulse dose and the time of observation. While such a suggestion of uniformity in time is certainly true for a broad range of radiation annealing phenomena, it may not hold for some ranges of the variables of interest (temperature, dose rate, etc.). A response function is projected which is dependent on two variables: the time of observation and the time of the impulse dose. This dependence on two variables allows us to extend the theory to the treatment of a variable dose rate. Finally, the linear theory is generalized to the case in which the response is nonlinear with impulse dose, but is proportional to some impulse function of dose. A method to determine both the impulse and response functions is presented.

Exposure-Response Modeling to Characterize the Relationship Between Ixekizumab Serum Drug Concentrations and Efficacy Responses at Week 12 in Patients With Moderate to Severe Plaque Psoriasis.

PubMed

Chigutsa, Emmanuel; de Mendizabal, Nieves Velez; Chua, Laiyi; Heathman, Michael; Friedrich, Stuart; Jackson, Kimberley; Reich, Kristian

2018-06-07

Ixekizumab, a high-affinity monoclonal antibody, selectively targets interleukin-17A and has been shown to be efficacious in the treatment of moderate to severe psoriasis. The objective was to describe the relationship between ixekizumab concentrations and efficacy response (static Physician Global Assessment [sPGA] and the Psoriasis Activity and Severity Index [PASI) scores] after 12 weeks of ixekizumab treatment in psoriasis patients from 3 phase 3 studies. Data from 2888 psoriasis patients randomized to receive placebo or 80 mg ixekizumab every 2 weeks or every 4 weeks were analyzed. Separate logistic regression models describing the relationship between ixekizumab concentrations and sPGA or PASI scores at week 12 were used to determine the probability of patients achieving a response and to investigate the impact of various patient factors other than drug concentrations on response rates. Both dosing regimens were efficacious, with higher rates of response achieved with the higher range of observed ixekizumab concentrations after every-2-week dosing. Although higher bodyweight, palmoplantar involvement, lower baseline disease state, or high baseline C-reactive protein were associated with slightly lower response rates, the magnitude of effect of these factors on sPGA(0,1) response was small, with all subgroups able to achieve high levels of response. Other factors tested had no effect including age, sex, and antidrug antibody status. Logistic regression modeling of ixekizumab concentration and efficacy data accurately identified the proportion of responders using sPGA or PASI end points. The higher concentration ranges achieved with 80 mg every 2 weeks versus every 4 weeks were associated with higher response levels. © 2018, The American College of Clinical Pharmacology.

The effects of immersiveness on physiology.

PubMed

Wiederhold, B K; Davis, R; Wiederhold, M D

1998-01-01

The effects of varying levels of immersion in virtual reality environments on participant's heart rate, respiration rate, peripheral skin temperature, and skin resistance levels were examined. Subjective reports of presence were also noted. Participants were presented with a virtual environment of an airplane flight both as seen from a two-dimensional computer screen and as seen from within a head-mounted display. Subjects were randomly assigned to different order of conditions presented, but all subjects received both conditions. Differences between the non-phobics' physiological responses and the phobic's response when placed in a virtual environment related to the phobia were noted. Also noted were changes in physiology based on degree of immersion.

Population-dependent effects of ocean acidification.

PubMed

Wood, Hannah L; Sundell, Kristina; Almroth, Bethanie Carney; Sköld, Helén Nilsson; Eriksson, Susanne P

2016-04-13

Elevated carbon dioxide levels and the resultant ocean acidification (OA) are changing the abiotic conditions of the oceans at a greater rate than ever before and placing pressure on marine species. Understanding the response of marine fauna to this change is critical for understanding the effects of OA. Population-level variation in OA tolerance is highly relevant and important in the determination of ecosystem resilience and persistence, but has received little focus to date. In this study, whether OA has the same biological consequences in high-salinity-acclimated population versus a low-salinity-acclimated population of the same species was investigated in the marine isopod Idotea balthica.The populations were found to have physiologically different responses to OA. While survival rate was similar between the two study populations at a future CO2 level of 1000 ppm, and both populations showed increased oxidative stress, the metabolic rate and osmoregulatory activity differed significantly between the two populations. The results of this study demonstrate that the physiological response to OA of populations from different salinities can vary. Population-level variation and the environment provenance of individuals used in OA experiments should be taken into account for the evaluation and prediction of climate change effects. © 2016 The Author(s).

Population-dependent effects of ocean acidification

PubMed Central

Wood, Hannah L.; Sundell, Kristina; Almroth, Bethanie Carney; Sköld, Helén Nilsson; Eriksson, Susanne P.

2016-01-01

Elevated carbon dioxide levels and the resultant ocean acidification (OA) are changing the abiotic conditions of the oceans at a greater rate than ever before and placing pressure on marine species. Understanding the response of marine fauna to this change is critical for understanding the effects of OA. Population-level variation in OA tolerance is highly relevant and important in the determination of ecosystem resilience and persistence, but has received little focus to date. In this study, whether OA has the same biological consequences in high-salinity-acclimated population versus a low-salinity-acclimated population of the same species was investigated in the marine isopod Idotea balthica. The populations were found to have physiologically different responses to OA. While survival rate was similar between the two study populations at a future CO2 level of 1000 ppm, and both populations showed increased oxidative stress, the metabolic rate and osmoregulatory activity differed significantly between the two populations. The results of this study demonstrate that the physiological response to OA of populations from different salinities can vary. Population-level variation and the environment provenance of individuals used in OA experiments should be taken into account for the evaluation and prediction of climate change effects. PMID:27053741

The Effects of Viewing R-Rated Movie Scenes That Objectify Women on Perceptions of Date Rape.

ERIC Educational Resources Information Center

Milburn, Michael A.; Mather, Roxanne; Conrad, Sheree D.

2000-01-01

Tested the effects of viewing R-rated films on perceptions of female responsibility for and enjoyment of date or stranger rape. Participants viewed nonviolent scenes objectifying and degrading women sexually or animated film scenes. They read a fictitious magazine account of a date or stranger rape. The study showed that males who viewed the…

Opposing effects of reward and punishment on human vigor

PubMed Central

Griffiths, Benjamin; Beierholm, Ulrik R.

2017-01-01

The vigor with which humans and animals engage in a task is often a determinant of the likelihood of the task’s success. An influential theoretical model suggests that the speed and rate at which responses are made should depend on the availability of rewards and punishments. While vigor facilitates the gathering of rewards in a bountiful environment, there is an incentive to slow down when punishments are forthcoming so as to decrease the rate of punishments, in conflict with the urge to perform fast to escape punishment. Previous experiments confirmed the former, leaving the latter unanswered. We tested the influence of punishment in an experiment involving economic incentives and contrasted this with reward related behavior on the same task. We found that behavior corresponded with the theoretical model; while instantaneous threat of punishment caused subjects to increase the vigor of their response, subjects’ response times would slow as the overall rate of punishment increased. We quantitatively show that this is in direct contrast to increases in vigor in the face of increased overall reward rates. These results highlight the opposed effects of rewards and punishments and provide further evidence for their roles in the variety of types of human decisions. PMID:28205567

Perceived effectiveness of fear appeals in AIDS education: relationship to ethnicity, gender, age, and group membership.

PubMed

Rhodes, F; Wolitski, R J

1990-01-01

A study was conducted with 261 community residents, college students, and intravenous drug users to investigate perceived effectiveness of fear appeals in AIDS education posters. Experimental posters with high-fear pictures portraying severe consequences of AIDS and low-fear posters that were neutral regarding disease severity were evaluated in terms of their perceived effectiveness in motivating people to use condoms. Posters also contained written messages communicating high and low levels of personal vulnerability and response efficacy. High-severity/fear posters were rated as significantly more effective than low-severity/fear posters (p less than .0001), but response efficacy and personal vulnerability were significant only in interaction with other variables (p less than .01). Age, gender, ethnicity, and group membership did not, in general, influence rated effectiveness. However, group membership and age were significant as interactions with severity/fear level and response efficacy, respectively (p less than .01). Subjects showed no differential preference for posters portraying individuals whose ethnicity was the same as their own. Findings confirmed previous research supporting the effectiveness of fear appeals and suggest that fear-oriented appeals may be effective in promoting changes in community norms and motivating individuals to adopt AIDS risk-reduction strategies.

Impacts of environmental variability on desiccation rate, plastic responses and population dynamics of Glossina pallidipes.

PubMed

Kleynhans, E; Clusella-Trullas, S; Terblanche, J S

2014-02-01

Physiological responses to transient conditions may result in costly responses with little fitness benefits, and therefore, a trade-off must exist between the speed of response and the duration of exposure to new conditions. Here, using the puparia of an important insect disease vector, Glossina pallidipes, we examine this potential trade-off using a novel combination of an experimental approach and a population dynamics model. Specifically, we explore and dissect the interactions between plastic physiological responses, treatment-duration and -intensity using an experimental approach. We then integrate these experimental results from organismal water-balance data and their plastic responses into a population dynamics model to examine the potential relative fitness effects of simulated transient weather conditions on population growth rates. The results show evidence for the predicted trade-off for plasticity of water loss rate (WLR) and the duration of new environmental conditions. When altered environmental conditions lasted for longer durations, physiological responses could match the new environmental conditions, and this resulted in a lower WLR and lower rates of population decline. At shorter time-scales however, a mismatch between acclimation duration and physiological responses was reflected by reduced overall population growth rates. This may indicate a potential fitness cost due to insufficient time for physiological adjustments to take place. The outcomes of this work therefore suggest plastic water balance responses have both costs and benefits, and these depend on the time-scale and magnitude of variation in environmental conditions. These results are significant for understanding the evolution of plastic physiological responses and changes in population abundance in the context of environmental variability. © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

Norepinephrine and impulsivity: Effects of acute yohimbine

PubMed Central

Swann, Alan C.; Lijffijt, Marijn; Lane, Scott D.; Cox, Blake; Steinberg, Joel L.; Moeller, F. Gerard

2013-01-01

Rationale Rapid-response impulsivity, characterized by inability to withhold response to a stimulus until it is adequately appraised, is associated with risky behavior and may be increased in a state-dependent manner by norepinephrine. Objective We assessed effects of yohimbine, which increases norepinephrine release by blocking alpha-2 noradrenergic receptors, on plasma catecholamine metabolites, blood pressure, subjective symptoms, and laboratory-measured rapid-response impulsivity. Methods Subjects were twenty-three healthy controls recruited from the community, with normal physical examination and ECG, and negative history for hypertension, cardiovascular illness, and Axis I or II disorder. Blood pressure, pulse, and behavioral measures were obtained before and periodically after 0.4 mg/kg oral yohimbine or placebo in a randomized, counterbalanced design. Metabolites of norepinephrine (3-methoxy-4-hydroxyphenylglycol, MHPG; vanillylmandelic acid, VMA) and dopamine (homovanillic acid, HVA) were measured by high pressure liquid chromatography with electrochemical detection. Rapid-response impulsivity was measured by commission errors and reaction times on the Immediate Memory Task (IMT), a continuous performance test designed to measure impulsivity and attention. Results Yohimbine increased plasma MHPG and VMA but not HVA. Yohimbine increased systolic and diastolic blood pressure and pulse rate. On the IMT, yohimbine increased impulsive errors and impulsive response bias and accelerated reaction times. Yohimbine-associated increase in plasma MHPG correlated with increased impulsive response rates. Time courses varied; effects on blood pressure generally preceded those on metabolites and test performance. Conclusions These effects are consistent with increased rapid-response impulsivity after pharmacological noradrenergic stimulation in healthy controls. Labile noradrenergic responses, or increased sensitivity to norepinephrine, may increase risk for impulsive behavior. PMID:23559222

Second-order schedules of token reinforcement with pigeons: effects of fixed- and variable-ratio exchange schedules.

PubMed

Foster, T A; Hackenberg, T D; Vaidya, M

2001-09-01

Pigeons' key pecks produced food under second-order schedules of token reinforcement, with light-emitting diodes serving as token reinforcers. In Experiment 1, tokens were earned according to a fixed-ratio 50 schedule and were exchanged for food according to either fixed-ratio or variable-ratio exchange schedules, with schedule type varied across conditions. In Experiment 2, schedule type was varied within sessions using a multiple schedule. In one component, tokens were earned according to a fixed-ratio 50 schedule and exchanged according to a variable-ratio schedule. In the other component, tokens were earned according to a variable-ratio 50 schedule and exchanged according to a fixed-ratio schedule. In both experiments, the number of responses per exchange was varied parametrically across conditions, ranging from 50 to 400 responses. Response rates decreased systematically with increases in the fixed-ratio exchange schedules, but were much less affected by changes in the variable-ratio exchange schedules. Response rates were consistently higher under variable-ratio exchange schedules than tinder comparable fixed-ratio exchange schedules, especially at higher exchange ratios. These response-rate differences were due both to greater pre-ratio pausing and to lower local rates tinder the fixed-ratio exchange schedules. Local response rates increased with proximity to food under the higher fixed-ratio exchange schedules, indicative of discriminative control by the tokens.

Single and combined effects of microcystin- and saxitoxin-producing cyanobacteria on the fitness and antioxidant defenses of cladocerans.

PubMed

da S Ferrão-Filho, Aloysio; de Abreu S Silva, Daniel; de Oliveira, Taissa A; de Magalhães, Valéria Freitas; Pflugmacher, Stephan; da Silva, Eduardo Mendes

2017-10-01

Cyanobacteria produce different toxic compounds that affect animal life, among them hepatotoxins and neurotoxins. Because cyanobacteria are able to produce a variety of toxic compounds at the same time, organisms may be, generally, subjected to their combined action. In the present study, we demonstrate the single and combined effects on cladocerans of cyanobacteria that produce microcystins (hepatotoxins) and saxitoxins (neurotoxins). Animals were exposed (either singly or combined) to 2 strains of cyanobacteria isolated from the same environment (Funil Reservoir, Rio de Janeiro, Brazil). The effects on clearance rate, mobility, survivorship, fecundity, population increase rate (r), and the antioxidant enzymes glutathione-S-transferase (GST) and catalase (CAT) were measured. Cladoceran species showed a variety of responses to cyanobacterial exposures, going from no effect to impairment of swimming movement, lower survivorship, fecundity, and general fitness (r). Animals ingested cyanobacteria in all treatments, although at lower rates than good food (green algae). Antioxidant defense responses were in accordance with fitness responses, suggesting that oxidative stress may be related to such effects. The present study emphasizes the need for testing combined actions of different classes of toxins, because this is often, and most likely, the scenario in a more eutrophic world with global climatic changes. Environ Toxicol Chem 2017;36:2689-2697. © 2017 SETAC. © 2017 SETAC.

The benefits of modified FOLFIRINOX for advanced pancreatic cancer and its induced adverse events: a systematic review and meta-analysis.

PubMed

Tong, Hongxuan; Fan, Zhu; Liu, Biyuan; Lu, Tao

2018-06-06

FOLFIRINOX has been one of the first-line options for advanced pancreatic cancer, even though it induces significant adverse effects. Several institutions have begun using modified FOLFIRINOX to decrease its side effects and increase its tolerability. We systematically investigated the outcome from patients who initially received modified FOLFIRINOX as a chemotherapy regimen for advanced pancreatic cancer. We used the random-model generic inverse variance method to analyse the binary data with 95% confidence intervals (CIs). Eleven studies were included in the meta-analysis with 563 total patients. The 6-month and 1-year overall survival (OS) rates of locally advanced pancreatic cancer (LAPC) were 90.9% and 76.2%. The 6-month and 1-year progression-free survival (PFS) rates of LAPC were 81.5% and 48.5%. The 6-month and 1-year OS rates of metastatic pancreatic cancer (MPC) were 79.7% and 47.6%. The 6-month and 1-year PFS rates of MPC were 56.3% and 20.6%. The following rates were also calculated: complete response rate (CR): 2.9%; partial response rate (PR): 35.9%; stable disease rate (SD): 41.2%; overall response rate (OR): 34.6%; disease control rate (DCR): 76.7%; progressive disease: 23.1%; and grade III/IV adverse events (AEs): neutropenia 23.1%, febrile neutropenia 4.8%, thrombocytopenia 4.8%, anaemia 5.7%, fatigue 11.5%, nausea 9.1%, diarrhoea 10.1%, vomiting 5.7%, neuropathy 3.8%, and increased ALT 5.7%. In conclusion, modified FOLFIRINOX could provide comparative survival benefits with fewer adverse events compared to the conventional dosage.

Diabetes and cardiometabolic risk factors in Cambodia: Results from two screening studies.

PubMed

Wagner, Julie; Naranjo, Diana; Khun, Touch; Seng, Serey; Horn, Ien S; Suttiratana, Sakinah C; Keuky, Lim

2018-02-01

Despite growing attention to diabetes throughout Asia, data from Southeast Asia are limited. This article reports rates of diabetes, hypertension, and obesity in Cambodia. Two studies were conducted across different regions of Cambodia: (i) a 2012 screening study across urban, semi-urban, and rural areas that used point-of-care capillary glucose for determination of diabetes (n = 13 997); and (ii) a 2005 epidemiological study with random selection from two main urban areas that used oral glucose tolerance tests for determination of diabetes (n = 1863). Blood pressure and anthropometrics were also measured. In the screening study, rates of diabetes were significantly higher in urban than rural sites, with intermediate rates in semi-urban areas. There was a significant dose-response effect for urbanicity on overweight, obesity, and waist:hip ratio, with higher rates for urban versus semi-urban and for semi-urban versus rural locales. Rural sites had the lowest rates of hypertension, followed by urban and semi-urban sites. Among people who screened positive for diabetes, there was a dose-response effect for urbanicity on undiagnosed diabetes; rates of previously undiagnosed diabetes were lowest in urban (51%), followed by semi-urban (55%) and rural (67%) locales. Rural participants reported the highest rates of smoking and alcohol use. In the urban epidemiological study, prevalence rates of diabetes and impaired glucose tolerance were approximately 10%, indicating a prevalence of total glucose intolerance of approximately 20%. In Cambodia, diabetes rates are high among urban residents and undiagnosed diabetes is highest among rural residents. A country-wide public health response is urgently needed; as development continues, rates of diabetes are expected to rise. © 2017 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.

An investigation of helicopter dynamic coupling using an analytical model

NASA Technical Reports Server (NTRS)

Keller, Jeffrey D.

1995-01-01

Many attempts have been made in recent years to predict the off-axis response of a helicopter to control inputs, and most have had little success. Since physical insight is limited by the complexity of numerical simulation models, this paper examines the off-axis response problem using an analytical model, with the goal of understanding the mechanics of the coupling. A new induced velocity model is extended to include the effects of wake distortion from pitch rate. It is shown that the inclusion of these results in a significant change in the lateral flap response to a steady pitch rate. The proposed inflow model is coupled with the full rotor/body dynamics, and comparisons are made between the model and flight test data for a UH-60 in hover. Results show that inclusion of induced velocity variations due to shaft rate improves correlation in the pitch response to lateral cycle inputs.

Motivation and expectancy influences in placebo responding: the mediating role of attention.

PubMed

Aigner, Carrie; Svanum, Soren

2014-12-01

Drawing upon research in perception and motivation, the current study proposes a motivation-attention model of placebo in which more motivated persons pay greater attention to placebo-related stimuli, directly influencing placebo response. We manipulated both motivation to respond to placebo and expectations of placebo response in a 2 × 2 design. Participants (N = 152) evaluated a series of placebo pheromones (slightly scented water) of potential romantic dates and made desirability ratings. Consistent with hypotheses, more highly motivated participants demonstrated greater placebo responses, as evidenced by higher desirability ratings of the "pheromone" and greater variability among ratings, when compared to less motivated participants. Moreover, the relation between motivation and placebo response was mediated by attention. Contrary to expectations, we found no effect for expectancy. These findings highlight the importance of motivation and the mediating factor of attention in placebo and support goal-oriented models of placebo. © 2014 International Union of Psychological Science.

Laser-based irradiation apparatus and methods for monitoring the dose-rate response of semiconductor devices

DOEpatents

Horn, Kevin M [Albuquerque, NM

2006-03-28

A scanned, pulsed, focused laser irradiation apparatus can measure and image the photocurrent collection resulting from a dose-rate equivalent exposure to infrared laser light across an entire silicon die. Comparisons of dose-rate response images or time-delay images from before, during, and after accelerated aging of a device, or from periodic sampling of devices from fielded operational systems allows precise identification of those specific age-affected circuit structures within a device that merit further quantitative analysis with targeted materials or electrical testing techniques. Another embodiment of the invention comprises a broad-beam, dose rate-equivalent exposure apparatus. The broad-beam laser irradiation apparatus can determine if aging has affected the device's overall functionality. This embodiment can be combined with the synchronized introduction of external electrical transients into a device under test to simulate the electrical effects of the surrounding circuitry's response to a radiation exposure.

Two-year efficacy of tocilizumab in patients with active rheumatoid arthritis in clinical practice.

PubMed

Notario Ferreira, Irene; Ferrer González, Miguel Angel; Morales Garrido, Pilar; González Utrilla, Alfonso; García Sanchez, Antonio; Soto Pino, María José; Suero Rosario, Evelyn; Caro Hernández, Cristina; Añón Oñate, Isabel; Pérez Albaladejo, Lorena; Cáliz Cáliz, Rafael

To evaluate the efficacy of tocilizumab (TCZ) in patients with rheumatoid arthritis (RA) in clinical practice, retention rates of the drug and predictors of response. We performed a descriptive, prospective, longitudinal, open-label study in patients receiving TCZ (8mg/kg/4 weeks) in a clinical practice setting. The clinical responses were evaluated using the European League Against Rheumatism (EULAR) response criteria, and the low activity and remission rates according to the Disease Activity Score 28-erythrocyte sedimentation rate (DAS28-ESR) and the Clinical Disease Activity Index (CDAI). The EULAR response rate was 86.63% and the DAS28 remission rate was 53.7% after 6 months of treatment; rates of low disease activity were 52.9% on CDAI and 47.1% on DAS28 at month 24. There were no statistically significant differences in EULAR response, rates of low activity and remission on DAS28 between patients receiving TCZ alone and those receiving TCZ in combination therapy, or between patients positive or negative for rheumatoid factor (RF) and/or anti-cyclic citrullinated peptide (anti-CCP) antibodies. The naïve biological therapy patients showed better remission and low activity rates after 6 months of treatment. The retention rate was 61% at month 24. Adverse events were among the most frequent causes of discontinuation. Tocilizumab is effective in RA, has a similar efficacy when used alone or in combination with synthetic disease-modifying antirheumatic drugs (DMARDs) and shows high retention rates. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Reumatología y Colegio Mexicano de Reumatología. All rights reserved.

Effectiveness of Albendazole for Hookworm Varies Widely by Community and Correlates with Nutritional Factors: A Cross-Sectional Study of School-Age Children in Ghana.

PubMed

Humphries, Debbie; Nguyen, Sara; Kumar, Sunny; Quagraine, Josephine E; Otchere, Joseph; Harrison, Lisa M; Wilson, Michael; Cappello, Michael

2017-02-08

Mass drug administration (MDA) targeting school-age children is recommended by the World Health Organization for the global control of soil-transmitted helminth (STH) infections. Although considered safe and cost-effective to deliver, benzimidazole anthelminthics are variably effective against the three most common STHs, and widespread use has raised concern about the potential for emerging resistance. To identify factors mediating response to albendazole, we conducted a cross-sectional study of hookworm infection in the Kintampo North Municipality of Ghana in 2011. Among 140 school-age children residing in five contiguous communities, the hookworm prevalence was 59% (82/140). The overall cure rate following administration of single-dose albendazole (400 mg) was 35% (27/76), with a community-wide fecal egg reduction rate (ERR) of 61% (95% confidence interval: 51.8-71.1). Significant disparities were observed in albendazole effectiveness by community, with a cure rate as low as 0% ( N = 24) in Jato Akuraa and ERRs ranging from 53% to 95% across the five study sites. Individual host factors associated with response to deworming treatment included time since last meal, pretreatment blood hemoglobin level, and mid-upper arm circumference. These data demonstrate significant community-level variation in the effectiveness of albendazole, even among populations living in close proximity. Identification of host factors that influence response to albendazole, most notably the timing of drug administration and nutritional factors, creates an opportunity to enhance the effectiveness of deworming through targeted interventions. These findings also demonstrate the importance of measuring anthelminthic response as part of the monitoring and evaluation of community-based deworming programs. © The American Society of Tropical Medicine and Hygiene.

Effectiveness of Albendazole for Hookworm Varies Widely by Community and Correlates with Nutritional Factors: A Cross-Sectional Study of School-Age Children in Ghana

PubMed Central

Humphries, Debbie; Nguyen, Sara; Kumar, Sunny; Quagraine, Josephine E.; Otchere, Joseph; Harrison, Lisa M.; Wilson, Michael; Cappello, Michael

2017-01-01

Mass drug administration (MDA) targeting school-age children is recommended by the World Health Organization for the global control of soil-transmitted helminth (STH) infections. Although considered safe and cost-effective to deliver, benzimidazole anthelminthics are variably effective against the three most common STHs, and widespread use has raised concern about the potential for emerging resistance. To identify factors mediating response to albendazole, we conducted a cross-sectional study of hookworm infection in the Kintampo North Municipality of Ghana in 2011. Among 140 school-age children residing in five contiguous communities, the hookworm prevalence was 59% (82/140). The overall cure rate following administration of single-dose albendazole (400 mg) was 35% (27/76), with a community-wide fecal egg reduction rate (ERR) of 61% (95% confidence interval: 51.8–71.1). Significant disparities were observed in albendazole effectiveness by community, with a cure rate as low as 0% (N = 24) in Jato Akuraa and ERRs ranging from 53% to 95% across the five study sites. Individual host factors associated with response to deworming treatment included time since last meal, pretreatment blood hemoglobin level, and mid-upper arm circumference. These data demonstrate significant community-level variation in the effectiveness of albendazole, even among populations living in close proximity. Identification of host factors that influence response to albendazole, most notably the timing of drug administration and nutritional factors, creates an opportunity to enhance the effectiveness of deworming through targeted interventions. These findings also demonstrate the importance of measuring anthelminthic response as part of the monitoring and evaluation of community-based deworming programs. PMID:27895280

Short-term intravenous citalopram augmentation in partial/nonresponders with major depression: a randomized placebo-controlled study.

PubMed

Altamura, Alfredo Carlo; Dell'Osso, Bernardo; Buoli, Massimiliano; Bosi, Monica; Mundo, Emanuela

2008-07-01

Approximately 30-45% of patients with major depressive episode (MDE) do not fully respond to standard recommended treatments and further strategies of intervention, including pharmacological augmentation, have been proposed for these patients. This study was aimed to evaluate the efficacy of short-term, low-dose (10 mg/day) intravenous (i.v.) citalopram augmentation versus placebo in a sample of patients with MDE and partial or no response to selective serotonin reuptake inhibitors (SSRIs). Thirty-six patients with a Diagnostic and Statistical Manual for Mental Disorders, 4th edition, text revision criteria MDE and partial or no response to oral SSRIs were selected and randomly assigned to citalopram (n=18) or to placebo (n=18) i.v. augmentation. The augmentation regimen lasted 5 consecutive days during which the patients were maintained on their current treatment with oral SSRIs. Analyses of variance with repeated measures on Hamilton Depression Rating Scale and Montgomery-Asberg Depression Rating Scale total scores, administered daily with blind-raters conditions, were done. With regard to the Hamilton Depression Rating Scale total scores, a significant time effect (F=42.02, P<0.0001) and timextreatment effect (F=21.17, P<0.0001) were found in favor of citalopram. Similar results were obtained from the analysis on Montgomery-Asberg Depression Rating Scale total scores: time effect (F=50.07, P<0.0001), timextreatment effect (F=19.91, P<0.0001), and treatment effect (F=4.07, P=0.05). Even though referred to a small sample, the present findings seem to suggest that short-term, low-dose, i.v. citalopram augmentation may be effective in depressed patients with partial or no response to oral SSRIs. Further controlled studies performed with double-blind conditions are warranted to confirm the present results.

Differential responses in yield of pumpkin (Cucurbita maxima L.) and nightshade (Solanum retroflexum Dun.) to the application of three animal manures.

PubMed

Azeez, J O; Van Averbeke, W; Okorogbona, A O M

2010-04-01

Crop responses to different manures differs considerably, however, the factors responsible for it have not been conclusively elucidated. Consequently, this study examined the biomass response of Cucurbita maxima and Solanum retroflexum to application rates of chicken and kraal manures of cattle and goat, and soil factors related to salinity. The crops' biomass yield increased linearly with increase in application rates of kraal and chicken manures, but steeper in the latter. Results showed that significant decline in biomass yield in chicken manure at rates above 8.5 tons ha(-1) were not due to salinity. The crops' response to cattle and goat kraal manures was linear but polynomial (cubic) in layer chicken manure. It was concluded that the yield decline in chicken manure was due to other manure factors except salinity, probably toxicity effect of the manure fatty acids. Further research was however, recommended to elucidate this claim. Copyright 2009 Elsevier Ltd. All rights reserved.

Difficult Temperament Moderates Links between Maternal Responsiveness and Children’s Compliance and Behavior Problems in Low-Income Families

PubMed Central

Kochanska, Grazyna; Kim, Sanghag

2012-01-01

Background Research has shown that interactions between young children’s temperament and the quality of care they receive predict the emergence of positive and negative socioemotional developmental outcomes. This multi-method study addresses such interactions, using observed and mother-rated measures of difficult temperament, children’s committed, self-regulated compliance and externalizing problems, and mothers’ responsiveness in a low-income sample. Methods In 186 30-month-old children, difficult temperament was observed in the laboratory (as poor effortful control and high anger proneness), and rated by mothers. Mothers’ responsiveness was observed in lengthy naturalistic interactions at 30 and 33 months. At 40 months, children’s committed compliance and externalizing behavior problems were assessed using observations and several well-established maternal report instruments. Results Parallel significant interactions between child difficult temperament and maternal responsiveness were found across both observed and mother-rated measures of temperament. For difficult children, responsiveness had a significant effect such that those children were more compliant and had fewer externalizing problems when they received responsive care, but were less compliant and had more behavior problems when they received unresponsive care. For children with easy temperaments, maternal responsiveness and developmental outcomes were unrelated. All significant interactions reflected the diathesis-stress model. There was no evidence of differential susceptibility, perhaps due to the pervasive stress present in the ecology of the studied families. Conclusions Those findings add to the growing body of evidence that for temperamentally difficult children, unresponsive parenting exacerbates risks for behavior problems, but responsive parenting can effectively buffer risks conferred by temperament. PMID:23057713

Treatment efficacy and safety of low-dose azathioprine in chronic active ulcerative colitis patients: A meta-analysis and systemic review.

PubMed

Luan, Zi Jian; Li, Yue; Zhao, Xin Yu; Wang, Li; Sun, Ying Hao; Wang, Shi Yao; Qian, Jia Ming

2016-10-01

To evaluate the efficacy and safety of low-dose azathioprine (AZA) in treating patients with chronic active ulcerative colitis (UC). A literature search of Medline, Embase, the Cochrane Library, Web of Science, Wanfang Database, CNKI, SinoMed, VIP Chinese Science and the Technology Journals Database was conducted to identify eligible studies that evaluated the efficacy and safety of low-dose azathioprine (AZA) in treating patients with chronic active UC published up to 15 July 2015. Data were extracted from the studies, including clinical efficacy (response rate, adverse drug reaction [ADR] rate, steroid withdrawal rate and relapse rate) and endoscopic improvement (endoscopic remission rate and mucosal healing rate). Six studies with 211 patients were eligible for the analysis. The overall response rates after 6 and 12 months of treatment were 78.0% (95% confidence interval [CI] 71.0-85.0%) and 88.0% (95% CI 80.0-96.0%), respectively. The overall ADR rate was 25.0% (95% CI 18.0-31.0%). Endoscopic response rate was around 85.0%, while the endoscopic remission rates and mucosal healing rates after 6 and 12 months of treatment were above 60.0% and 70.0%, respectively. The steroid withdrawal rate and relapse rate were in moderate to high heterogeneity. Egger's test indicated that there was no publication bias for studies regarding the 6-month response rate and ADR rate. Low-dose AZA is effective and safe in the treatment of chronic active UC patients. However, randomized controlled trials with large sample sizes are needed to draw definitive conclusions. © 2016 Chinese Medical Association Shanghai Branch, Chinese Society of Gastroenterology, Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.

Recruitment methods for survey research: Findings from the Mid-South Clinical Data Research Network.

PubMed

Heerman, William J; Jackson, Natalie; Roumie, Christianne L; Harris, Paul A; Rosenbloom, S Trent; Pulley, Jill; Wilkins, Consuelo H; Williams, Neely A; Crenshaw, David; Leak, Cardella; Scherdin, Jon; Muñoz, Daniel; Bachmann, Justin; Rothman, Russell L; Kripalani, Sunil

2017-11-01

The objective of this study was to report survey response rates and demographic characteristics of eight recruitment approaches to determine acceptability and effectiveness of large-scale patient recruitment among various populations. We conducted a cross sectional analysis of survey data from two large cohorts. Patients were recruited from the Mid-South Clinical Data Research Network using clinic-based recruitment, research registries, and mail, phone, and email approaches. Response rates are reported as patients who consented for the survey divided by the number of eligible patients approached. We contacted more than 90,000 patients and 13,197 patients completed surveys. Median age was 56.3years (IQR 40.9, 67.4). Racial/ethnic distribution was 84.1% White, non-Hispanic; 9.9% Black, non-Hispanic; 1.8% Hispanic; and 4.0% other, non-Hispanic. Face-to-face recruitment had the highest response rate of 94.3%, followed by participants who "opted-in" to a registry (76%). The lowest response rate was for unsolicited emails from the clinic (6.1%). Face-to-face recruitment enrolled a higher percentage of participants who self-identified as Black, non-Hispanic compared to other approaches (18.6% face-to-face vs. 8.4% for email). Technology-enabled recruitment approaches such as registries and emails are effective for recruiting but may yield less racial/ethnic diversity compared to traditional, more time-intensive approaches. Copyright © 2017. Published by Elsevier Inc.

Arousal-state modulation in children with AD/HD.

PubMed

Benikos, Nicholas; Johnstone, Stuart J

2009-01-01

To investigate the effect of arousal-state modulation, via manipulation of stimulus event-rate, on response inhibition in children with Attention-Deficit/Hyperactivity disorder (AD/HD) using behavioural and ERP measures. Eighteen children with AD/HD, aged 7-14years, and 18 age-and sex-matched controls performed a cued visual Go/Nogo task (70% Go) with stimuli presented at fast, medium and slow event-rates. Task performance and ERPs to Warning, Go and Nogo stimuli, as well as preparation between the S1-S2 interval, were examined for group differences. AD/HD subjects displayed poorer response inhibition during the fast condition, accompanied by a reduced Nogo P3. Group differences during the fast rate extended to Warning cues, with the AD/HD group showing ERP evidence of atypical orienting/preparation, as indexed by the early and late CNV, and early sensory/attentive processing prior to S2. Although deficient response inhibition has been proposed as the core deficit in AD/HD, the results of the present study highlight the key role of energetic factors. Furthermore, group differences found to cues suggest that this effect extends to the processing of task-irrelevant stimuli. This was the first ERP Go/Nogo task investigation using three event-rates, and the results support the theory that state factors may contribute to response inhibition deficits in AD/HD.

Impact of tocilizumab therapy on antibody response to influenza vaccine in patients with rheumatoid arthritis.

PubMed

Mori, Shunsuke; Ueki, Yukitaka; Hirakata, Naoyuki; Oribe, Motohiro; Hidaka, Toshihiko; Oishi, Kazunori

2012-12-01

We assessed the influence of tocilizumab (TCZ), a humanised monoclonal anti-interleukin-6 receptor antibody, on antibody response following influenza vaccination in patients with rheumatoid arthritis (RA). A total of 194 RA patients received inactive trivalent influenza vaccination (A/H1N1, A/H3N2 and B/B1 strains). All patients were classified into the TCZ (n=62), TCZ+methotrexate (MTX) (n=49), MTX (n=65) and RA control (n=18) groups. Antibody titres were measured before and 4-6 weeks after vaccination using the haemagglutination inhibitory assay. For the A/H1N1 and A/H3N2 strains, the TCZ and TCZ+MTX groups achieved fold increases of 9.9-14.5, postvaccination seroprotection rates greater than 70% and seroresponse rates greater than 40%. For the B/B1 strain, seroresponse rates were approximately 30%, but fold increases and seroprotection rates were 5.0-5.4 and greater than 70%, respectively, in these treatment groups. MTX had a negative impact on vaccination efficacy, but adequate responses for protection were nevertheless demonstrated in the MTX group. Neither severe adverse effects nor RA flares were observed. TCZ does not hamper antibody response to influenza vaccine in RA patients. Influenza vaccination is considered effective in protecting RA patients receiving TCZ therapy with or without MTX.

Climate change and functional traits affect population dynamics of a long-lived seabird.

PubMed

Jenouvrier, Stéphanie; Desprez, Marine; Fay, Remi; Barbraud, Christophe; Weimerskirch, Henri; Delord, Karine; Caswell, Hal

2018-07-01

Recent studies unravelled the effect of climate changes on populations through their impact on functional traits and demographic rates in terrestrial and freshwater ecosystems, but such understanding in marine ecosystems remains incomplete. Here, we evaluate the impact of the combined effects of climate and functional traits on population dynamics of a long-lived migratory seabird breeding in the southern ocean: the black-browed albatross (Thalassarche melanophris, BBA). We address the following prospective question: "Of all the changes in the climate and functional traits, which would produce the biggest impact on the BBA population growth rate?" We develop a structured matrix population model that includes the effect of climate and functional traits on the complete BBA life cycle. A detailed sensitivity analysis is conducted to understand the main pathway by which climate and functional trait changes affect the population growth rate. The population growth rate of BBA is driven by the combined effects of climate over various seasons and multiple functional traits with carry-over effects across seasons on demographic processes. Changes in sea surface temperature (SST) during late winter cause the biggest changes in the population growth rate, through their effect on juvenile survival. Adults appeared to respond to changes in winter climate conditions by adapting their migratory schedule rather than by modifying their at-sea foraging activity. However, the sensitivity of the population growth rate to SST affecting BBA migratory schedule is small. BBA foraging activity during the pre-breeding period has the biggest impact on population growth rate among functional traits. Finally, changes in SST during the breeding season have little effect on the population growth rate. These results highlight the importance of early life histories and carry-over effects of climate and functional traits on demographic rates across multiple seasons in population response to climate change. Robust conclusions about the roles of various phases of the life cycle and functional traits in population response to climate change rely on an understanding of the relationships of traits to demographic rates across the complete life cycle. © 2018 The Authors. Journal of Animal Ecology published by John Wiley & Sons Ltd oxn behalf of British Ecological Society.

Cystine improves survival rates in a LPS-induced sepsis mouse model.

PubMed

Tanaka, Kenji A K; Kurihara, Shigekazu; Shibakusa, Tetsuro; Chiba, Yasumasa; Mikami, Takashi

2015-12-01

The control of inflammation is important for suppressing severe sepsis. Oral administration of cystine and theanine have been shown to suppress inflammatory responses due to invasion. Furthermore, the uptake of cystine into monocytes is promoted by exposure to lipopolysaccharide (LPS). In the present study, the effects of cystine were examined in the context of inflammatory responses. Cystine was orally administered to mice, and the levels of interleukin (IL)-6 in the blood and spleen and the survival rates were calculated after the administration of LPS. The effects of cystine as well as neutralising anti-IL-10 antibodies on the LPS-induced production of IL-6 and IL-10 were examined in a monocyte cell line. The oral administration of cystine reduced IL-6 levels in the blood and spleen after LPS stimulation and improved survival rates. The addition of cystine to monocytes suppressed LPS-induced IL-6 production but enhanced IL-10 production. A neutralising anti-IL-10 antibody eliminated the inhibitory effects of cystine on the LPS-induced production of IL-6. The oral administration of cystine suppressed IL-6 production following LPS stimulation and improved survival rates in mice with LPS-induced sepsis. The enhanced production of IL-10 by monocytes may be involved in this anti-inflammatory response. Copyright © 2014 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

Impact of motorboats on fish embryos depends on engine type

PubMed Central

Jain-Schlaepfer, Sofia; Fakan, Eric; Rummer, Jodie L; Simpson, Stephen D; McCormick, Mark I

2018-01-01

Abstract Human generated noise is changing the natural underwater soundscapes worldwide. The most pervasive sources of underwater anthropogenic noise are motorboats, which have been found to negatively affect several aspects of fish biology. However, few studies have examined the effects of noise on early life stages, especially the embryonic stage, despite embryo health being critical to larval survival and recruitment. Here, we used a novel setup to monitor heart rates of embryos from the staghorn damselfish (Amblyglyphidodon curacao) in shallow reef conditions, allowing us to examine the effects of in situ boat noise in context with real-world exposure. We found that the heart rate of embryos increased in the presence of boat noise, which can be associated with the stress response. Additionally, we found 2-stroke outboard-powered boats had more than twice the effect on embryo heart rates than did 4-stroke powered boats, showing an increase in mean individual heart rate of 1.9% and 4.6%, respectively. To our knowledge this is the first evidence suggesting boat noise elicits a stress response in fish embryo and highlights the need to explore the ecological ramifications of boat noise stress during the embryo stage. Also, knowing the response of marine organisms caused by the sound emissions of particular engine types provides an important tool for reef managers to mitigate noise pollution. PMID:29593871

Impact of motorboats on fish embryos depends on engine type.

PubMed

Jain-Schlaepfer, Sofia; Fakan, Eric; Rummer, Jodie L; Simpson, Stephen D; McCormick, Mark I

2018-01-01

Human generated noise is changing the natural underwater soundscapes worldwide. The most pervasive sources of underwater anthropogenic noise are motorboats, which have been found to negatively affect several aspects of fish biology. However, few studies have examined the effects of noise on early life stages, especially the embryonic stage, despite embryo health being critical to larval survival and recruitment. Here, we used a novel setup to monitor heart rates of embryos from the staghorn damselfish ( Amblyglyphidodon curacao ) in shallow reef conditions, allowing us to examine the effects of in situ boat noise in context with real-world exposure. We found that the heart rate of embryos increased in the presence of boat noise, which can be associated with the stress response. Additionally, we found 2-stroke outboard-powered boats had more than twice the effect on embryo heart rates than did 4-stroke powered boats, showing an increase in mean individual heart rate of 1.9% and 4.6%, respectively. To our knowledge this is the first evidence suggesting boat noise elicits a stress response in fish embryo and highlights the need to explore the ecological ramifications of boat noise stress during the embryo stage. Also, knowing the response of marine organisms caused by the sound emissions of particular engine types provides an important tool for reef managers to mitigate noise pollution.

Host Plant Physiology and Mycorrhizal Functioning Shift across a Glacial through Future [CO2] Gradient1[OPEN

PubMed Central

Mullinix, George W.R.; Ward, Joy K.

2016-01-01

Rising atmospheric carbon dioxide concentration ([CO2]) may modulate the functioning of mycorrhizal associations by altering the relative degree of nutrient and carbohydrate limitations in plants. To test this, we grew Taraxacum ceratophorum and Taraxacum officinale (native and exotic dandelions) with and without mycorrhizal fungi across a broad [CO2] gradient (180–1,000 µL L−1). Differential plant growth rates and vegetative plasticity were hypothesized to drive species-specific responses to [CO2] and arbuscular mycorrhizal fungi. To evaluate [CO2] effects on mycorrhizal functioning, we calculated response ratios based on the relative biomass of mycorrhizal (MBio) and nonmycorrhizal (NMBio) plants (RBio = [MBio − NMBio]/NMBio). We then assessed linkages between RBio and host physiology, fungal growth, and biomass allocation using structural equation modeling. For T. officinale, RBio increased with rising [CO2], shifting from negative to positive values at 700 µL L−1. [CO2] and mycorrhizal effects on photosynthesis and leaf growth rates drove shifts in RBio in this species. For T. ceratophorum, RBio increased from 180 to 390 µL L−1 and further increases in [CO2] caused RBio to shift from positive to negative values. [CO2] and fungal effects on plant growth and carbon sink strength were correlated with shifts in RBio in this species. Overall, we show that rising [CO2] significantly altered the functioning of mycorrhizal associations. These symbioses became more beneficial with rising [CO2], but nonlinear effects may limit plant responses to mycorrhizal fungi under future [CO2]. The magnitude and mechanisms driving mycorrhizal-CO2 responses reflected species-specific differences in growth rate and vegetative plasticity, indicating that these traits may provide a framework for predicting mycorrhizal responses to global change. PMID:27573369

Effects of Recreation on Animals Revealed as Widespread through a Global Systematic Review

PubMed Central

Reed, Sarah E.; Merenlender, Adina M.; Crooks, Kevin R.

2016-01-01

Outdoor recreation is typically assumed to be compatible with biodiversity conservation and is permitted in most protected areas worldwide. However, increasing numbers of studies are discovering negative effects of recreation on animals. We conducted a systematic review of the scientific literature and analyzed 274 articles on the effects of non-consumptive recreation on animals, across all geographic areas, taxonomic groups, and recreation activities. We quantified trends in publication rates and outlets, identified knowledge gaps, and assessed evidence for effects of recreation. Although publication rates are low and knowledge gaps remain, the evidence was clear with over 93% of reviewed articles documenting at least one effect of recreation on animals, the majority of which (59%) were classified as negative effects. Most articles focused on mammals (42% of articles) or birds (37%), locations in North America (37.7%) or Europe (26.6%), and individual-level responses (49%). Meanwhile, studies of amphibians, reptiles, and fish, locations in South America, Asia, and Africa, and responses at the population and community levels are lacking. Although responses are likely to be species-specific in many cases, some taxonomic groups (e.g., raptors, shorebirds, ungulates, and corals) had greater evidence for an effect of recreation. Counter to public perception, non-motorized activities had more evidence for a negative effect of recreation than motorized activities, with effects observed 1.2 times more frequently. Snow-based activities had more evidence for an effect than other types of recreation, with effects observed 1.3 times more frequently. Protecting biodiversity from potentially harmful effects of recreation is a primary concern for conservation planners and land managers who face increases in park visitation rates; accordingly, there is demand for science-based information to help solve these dilemmas. PMID:27930730

Biological effects of α-radiation exposure by (241)Am in Arabidopsis thaliana seedlings are determined both by dose rate and (241)Am distribution.

PubMed

Biermans, Geert; Horemans, Nele; Vanhoudt, Nathalie; Vandenhove, Hildegarde; Saenen, Eline; Van Hees, May; Wannijn, Jean; Vangronsveld, Jaco; Cuypers, Ann

2015-11-01

Human activity has led to an increasing amount of radionuclides in the environment and subsequently to an increased risk of exposure of the biosphere to ionising radiation. Due to their high linear energy transfer, α-emitters form a threat to biota when absorbed or integrated in living tissue. Among these, (241)Am is of major concern due to high affinity for organic matter and high specific activity. This study examines the dose-dependent biological effects of α-radiation delivered by (241)Am at the morphological, physiological and molecular level in 14-day old seedlings of Arabidopsis thaliana after hydroponic exposure for 4 or 7 days. Our results show that (241)Am has high transfer to the roots but low translocation to the shoots. In the roots, we observed a transcriptional response of reactive oxygen species scavenging and DNA repair pathways. At the physiological and morphological level this resulted in a response which evolved from redox balance control and stable biomass at low dose rates to growth reduction, reduced transfer and redox balance decline at higher dose rates. This situation was also reflected in the shoots where, despite the absence of a transcriptional response, the control of photosynthesis performance and redox balance declined with increasing dose rate. The data further suggest that the effects in both organs were initiated in the roots, where the highest dose rates occurred, ultimately affecting photosynthesis performance and carbon assimilation. Though further detailed study of nutrient balance and (241)Am localisation is necessary, it is clear that radionuclide uptake and distribution is a major parameter in the global exposure effects on plant performance and health. Copyright © 2015 Elsevier Ltd. All rights reserved.

Imidacloprid-treated seed ingestion has lethal effect on adult partridges and reduces both breeding investment and offspring immunity.

PubMed

Lopez-Antia, Ana; Ortiz-Santaliestra, Manuel E; Mougeot, François; Mateo, Rafael

2015-01-01

The ingestion of imidacloprid treated seeds by farmland birds may result in exposure to toxic amounts of this insecticide. Here we report on the effects that the exposure to the recommended application rate and to 20% of that rate may produce on birds feeding on treated seeds. Experimental exposure to imidacloprid treated seeds was performed on red-legged partridges (Alectoris rufa) (n=15 pairs per treatment group: control, 20% or 100% of the recommended application rate) during two periods that corresponded to the autumn (duration of exposure: 25 days) and late winter (10 days) cereal sowing times in Spanish farmlands. We studied effects on the survival, body condition, oxidative stress biomarkers, plasma biochemistry, carotenoid-based coloration, T-cell mediated immune response and reproduction of exposed adult partridges, and on the survival and T-cell immune response of their chicks. The high dose (recommended application rate) killed all partridges, with mortality occurring faster in females than in males. The low dose (20% the recommended application rate) had no effect on mortality, but reduced levels of plasma biochemistry parameters (glucose, magnesium and lactate dehydrogenase), increased blood superoxide dismutase activity, produced changes in carotenoid-based integument coloration, reduced the clutch size, delayed the first egg lay date, increased egg yolk vitamins and carotenoids and depressed T-cell immune response of chicks. Moreover, the analysis of the livers of dead partridges revealed an accumulation of imidacloprid during exposure time. Despite the moratorium on the use of neonicotinoids in the European Union, birds may still be at high risk of poisoning by these pesticides through direct sources of exposure to coated seeds in autumn and winter. Copyright © 2014 Elsevier Inc. All rights reserved.

Effects of Atrazine, Metolachlor, Carbaryl and Chlorothalonil on Benthic Microbes and Their Nutrient Dynamics

PubMed Central

Elias, Daniel; Bernot, Melody J.

2014-01-01

Atrazine, metolachlor, carbaryl, and chlorothalonil are detected in streams throughout the U.S. at concentrations that may have adverse effects on benthic microbes. Sediment samples were exposed to these pesticides to quantify responses of ammonium, nitrate, and phosphate uptake by the benthic microbial community. Control uptake rates of sediments had net remineralization of nitrate (−1.58 NO3 µg gdm−1 h−1), and net assimilation of phosphate (1.34 PO4 µg gdm−1 h−1) and ammonium (0.03 NH4 µg gdm−1 h−1). Metolachlor decreased ammonium and phosphate uptake. Chlorothalonil decreased nitrate remineralization and phosphate uptake. Nitrate, ammonium, and phosphate uptake rates are more pronounced in the presence of these pesticides due to microbial adaptations to toxicants. Our interpretation of pesticide availability based on their water/solid affinities supports no effects for atrazine and carbaryl, decreasing nitrate remineralization, and phosphate assimilation in response to chlorothalonil. Further, decreased ammonium and phosphate uptake in response to metolachlor is likely due to affinity. Because atrazine target autotrophs, and carbaryl synaptic activity, effects on benthic microbes were not hypothesized, consistent with results. Metolachlor and chlorothalonil (non-specific modes of action) had significant effects on sediment microbial nutrient dynamics. Thus, pesticides with a higher affinity to sediments and/or broad modes of action are likely to affect sediment microbes' nutrient dynamics than pesticides dissolved in water or specific modes of action. Predicted nutrient uptake rates were calculated at mean and peak concentrations of metolachlor and chlorothalonil in freshwaters using polynomial equations generated in this experiment. We concluded that in natural ecosystems, peak chlorothalonil and metolachlor concentrations could affect phosphate and ammonium by decreasing net assimilation, and nitrate uptake rates by decreasing remineralization, relative to mean concentrations of metolachlor and chlorothalonil. Our regression equations can complement models of nitrogen and phosphorus availability in streams to predict potential changes in nutrient dynamics in response to pesticides in freshwaters. PMID:25275369

Activation of GLP-1 receptors on vascular smooth muscle cells reduces the autoregulatory response in afferent arterioles and increases renal blood flow.

PubMed

Jensen, Elisa P; Poulsen, Steen S; Kissow, Hannelouise; Holstein-Rathlou, Niels-Henrik; Deacon, Carolyn F; Jensen, Boye L; Holst, Jens J; Sorensen, Charlotte M

2015-04-15

Glucagon-like peptide (GLP)-1 has a range of extrapancreatic effects, including renal effects. The mechanisms are poorly understood, but GLP-1 receptors have been identified in the kidney. However, the exact cellular localization of the renal receptors is poorly described. The aim of the present study was to localize renal GLP-1 receptors and describe GLP-1-mediated effects on the renal vasculature. We hypothesized that renal GLP-1 receptors are located in the renal microcirculation and that activation of these affects renal autoregulation and increases renal blood flow. In vivo autoradiography using (125)I-labeled GLP-1, (125)I-labeled exendin-4 (GLP-1 analog), and (125)I-labeled exendin 9-39 (GLP-1 receptor antagonist) was performed in rodents to localize specific GLP-1 receptor binding. GLP-1-mediated effects on blood pressure, renal blood flow (RBF), heart rate, renin secretion, urinary flow rate, and Na(+) and K(+) excretion were investigated in anesthetized rats. Effects of GLP-1 on afferent arterioles were investigated in isolated mouse kidneys. Specific binding of (125)I-labeled GLP-1, (125)I-labeled exendin-4, and (125)I-labeled exendin 9-39 was observed in the renal vasculature, including afferent arterioles. Infusion of GLP-1 increased blood pressure, RBF, and urinary flow rate significantly in rats. Heart rate and plasma renin concentrations were unchanged. Exendin 9-39 inhibited the increase in RBF. In isolated murine kidneys, GLP-1 and exendin-4 significantly reduced the autoregulatory response of afferent arterioles in response to stepwise increases in pressure. We conclude that GLP-1 receptors are located in the renal vasculature, including afferent arterioles. Activation of these receptors reduces the autoregulatory response of afferent arterioles to acute pressure increases and increases RBF in normotensive rats. Copyright © 2015 the American Physiological Society.

Allowing Physicians to Choose the Value of Compensation for Participation in a Web-Based Survey: Randomized Controlled Trial.

PubMed

Turnbull, Alison E; O'Connor, Cristi L; Lau, Bryan; Halpern, Scott D; Needham, Dale M

2015-07-29

Survey response rates among physicians are declining, and determining an appropriate level of compensation to motivate participation poses a major challenge. To estimate the effect of permitting intensive care physicians to select their preferred level of compensation for completing a short Web-based survey on physician (1) response rate, (2) survey completion rate, (3) time to response, and (4) time spent completing the survey. A total of 1850 US intensivists from an existing database were randomized to receive a survey invitation email with or without an Amazon.com incentive available to the first 100 respondents. The incentive could be instantly redeemed for an amount chosen by the respondent, up to a maximum of US $50. The overall response rate was 35.90% (630/1755). Among the 35.4% (111/314) of eligible participants choosing the incentive, 80.2% (89/111) selected the maximum value. Among intensivists offered an incentive, the response was 6.0% higher (95% CI 1.5-10.5, P=.01), survey completion was marginally greater (807/859, 94.0% vs 892/991, 90.0%; P=.06), and the median number of days to survey response was shorter (0.8, interquartile range [IQR] 0.2-14.4 vs 6.6, IQR 0.3-22.3; P=.001), with no difference in time spent completing the survey. Permitting intensive care physicians to determine compensation level for completing a short Web-based survey modestly increased response rate and substantially decreased response time without decreasing the time spent on survey completion.

Allowing Physicians to Choose the Value of Compensation for Participation in a Web-Based Survey: Randomized Controlled Trial

PubMed Central

O'Connor, Cristi L; Lau, Bryan; Halpern, Scott D; Needham, Dale M

2015-01-01

Background Survey response rates among physicians are declining, and determining an appropriate level of compensation to motivate participation poses a major challenge. Objective To estimate the effect of permitting intensive care physicians to select their preferred level of compensation for completing a short Web-based survey on physician (1) response rate, (2) survey completion rate, (3) time to response, and (4) time spent completing the survey. Methods A total of 1850 US intensivists from an existing database were randomized to receive a survey invitation email with or without an Amazon.com incentive available to the first 100 respondents. The incentive could be instantly redeemed for an amount chosen by the respondent, up to a maximum of US $50. Results The overall response rate was 35.90% (630/1755). Among the 35.4% (111/314) of eligible participants choosing the incentive, 80.2% (89/111) selected the maximum value. Among intensivists offered an incentive, the response was 6.0% higher (95% CI 1.5-10.5, P=.01), survey completion was marginally greater (807/859, 94.0% vs 892/991, 90.0%; P=.06), and the median number of days to survey response was shorter (0.8, interquartile range [IQR] 0.2-14.4 vs 6.6, IQR 0.3-22.3; P=.001), with no difference in time spent completing the survey. Conclusions Permitting intensive care physicians to determine compensation level for completing a short Web-based survey modestly increased response rate and substantially decreased response time without decreasing the time spent on survey completion. PMID:26223821

Provider-patient in-office discussions of response to hepatitis C antiviral therapy and impact on patient comprehension.

PubMed

Hamilton, Heidi E; Nelson, Meaghan; Martin, Paul; Cotler, Scott J

2006-04-01

Providers need to communicate projected response rates effectively to enable patients with hepatitis C virus to make informed decisions about therapy. This study used interactional sociolinguistics (1) to evaluate how gastroenterologists and allied health professionals communicate information regarding response rates to antiviral therapy, (2) to determine how these discussions relate to where the patient is in the continuum of evaluation and treatment, (3) to assess whether patients were aligned with providers in their perceptions of response rates after office visits, and (4) to identify factors that improve provider-patient alignment. Gastroenterologists, allied health professionals, and patients with hepatitis C virus were videotaped and audiotaped during regularly scheduled visits. Postvisit interviews were conducted separately with patients and providers. Visits and postvisits were transcribed and analyzed using validated sociolinguistic techniques. The phase of hepatitis C virus treatment shaped the benchmarks of response talk, although across the treatment continuum providers overwhelmingly made strategic use of positive statistics, providing motivation. In postvisit interviews, 55% of providers and patients were aligned on response rates. Patients with a favorable outcome and patients who asked response-related questions in the visit were more likely to be aligned with providers. Areas identified for improvement included the tendency to discuss response rates before an individualized assessment could be made, balancing motivation and accuracy, and assessing the patient's perspective before delivering any bad news, if necessary. Sociolinguistic analysis provides a powerful tool to evaluate provider-patient interactions and to identify ways to improve in-office communication regarding antiviral therapy.

Effect of Loading Rate and Orientation on the Compressive Response of Human Cortical Bone

DTIC Science & Technology

2014-05-01

use thereof. Destroy this report when it is no longer needed. Do not return it to the originator. Army Research Laboratory Aberdeen Proving...quasi-static (0.001/s), intermediate (1/s), and dynamic (1000–2000/s) strain rates using a split-Hopkinson pressure bar to determine the strain rate...6 Figure 5. Strain rate and strain histories of human cortical bone specimen at high rate using bar signals

Mysid Population Responses to Resource Limitation Differ from those Predicted by Cohort Studies

EPA Science Inventory

Effects of anthropogenic stressors on animal populations are often evaluated by assembling vital rate responses from isolated cohort studies into a single demographic model. However, models constructed from cohort studies are difficult to translate into ecological predictions be...

The Effects of Demand-Responsive Parking on Transit Usage and Congestion: Evidence From Sfpark

DOT National Transportation Integrated Search

2017-09-01

Parking is a serious issue in many urban areas, especially those experiencing rapid population growth. To address this problem, some cities have implemented demand-responsive pricing programs, where parking prices vary depending on the occupancy rate...

Effect of short-term weight loss on mental stress-induced cardiovascular and pro-inflammatory responses in women.

PubMed

Endrighi, Romano; Hamer, Mark; Hackett, Ruth A; Carvalho, Livia A; Jackson, Sarah E; Wardle, Jane; Steptoe, Andrew

2015-01-01

Epidemiologic evidence links psychosocial stress with obesity but experimental studies examining the mechanisms that mediates the effect of stress on adiposity are scarce. The aim of this study was to investigate whether changes in adiposity following minimal weight loss affect heightened stress responses in women, and examine the role of the adipokine leptin in driving inflammatory responses. Twenty-three overweight or obese, but otherwise healthy, women (M age = 30.41 ± 8.0 years; BMI = 31.9 ± 4.1 kg/m(2)) completed standardized acute mental stress before and after a 9-week calorie restriction program designed to modify adiposity levels. Cardiovascular (blood pressure and heart rate) and inflammatory cytokines (leptin and interleukin-6; IL-6) responses to mental stress were assessed several times between baseline and a 45-min post-stress recovery period. There were modest changes in adiposity measures while the adipokine leptin was markedly reduced (-27%) after the intervention. Blood pressure reactivity was attenuated (-3.38 ± 1.39 mmHg) and heart rate recovery was improved (2.07 ± 0.96 Bpm) after weight loss. Blood pressure responses were inversely associated with changes in waist to hip ratio post intervention. Decreased levels of circulating leptin following weight loss were inversely associated with the IL-6 inflammatory response to stress (r = -0.47). We offered preliminary evidence suggesting that modest changes in adiposity following a brief caloric restriction program may yield beneficial effect on cardiovascular stress responses. In addition, reductions in basal leptin activity might be important in blunting pro-inflammatory responses. Large randomized trials of the effect of adiposity on autonomic responses are thus warranted.

Criterion Noise in Ratings-Based Recognition: Evidence from the Effects of Response Scale Length on Recognition Accuracy

ERIC Educational Resources Information Center

Benjamin, Aaron S.; Tullis, Jonathan G.; Lee, Ji Hae

2013-01-01

Rating scales are a standard measurement tool in psychological research. However, research has suggested that the cognitive burden involved in maintaining the criteria used to parcel subjective evidence into ratings introduces "decision noise" and affects estimates of performance in the underlying task. There has been debate over whether…

Tracking Students to 200 Percent of Normal Time: Effect on Institutional Graduation Rates. Issue Brief. NCES 2011-221

ERIC Educational Resources Information Center

Horn, Laura

2010-01-01

The 1990 Student Right-to-Know Act requires institutions to annually disclose graduation rates. To assist institutions in meeting this responsibility, the Integrated Postsecondary Education Data System (IPEDS) has collected institutional graduation rate data since 1997. Institutions eligible for federal student aid (Title IV funding) are required…

Response to "Rating Teachers Cheaper, Faster, and Better: Not so Fast": It's About Evidence

ERIC Educational Resources Information Center

Gargani, John; Strong, Michael

2015-01-01

In Gargani and Strong (2014), we describe The Rapid Assessment of Teacher Effectiveness (RATE), a new teacher evaluation instrument. Our account of the validation research associated with RATE inspired a review by Good and Lavigne (2015). Here, we reply to the main points of their review. We elaborate on the validity, reliability, theoretical…

FOLFOXIRI Plus Bevacizumab as Conversion Therapy for Patients With Initially Unresectable Metastatic Colorectal Cancer: A Systematic Review and Pooled Analysis.

PubMed

Tomasello, Gianluca; Petrelli, Fausto; Ghidini, Michele; Russo, Alessandro; Passalacqua, Rodolfo; Barni, Sandro

2017-07-13

The combination of fluorouracil, oxaliplatin, and irinotecan plus bevacizumab (FOLFOXIRI-Bev) is an established and effective first-line chemotherapy regimen for metastatic colorectal cancer. However, resection rates of metastases and overall survival with this schedule have never been systematically evaluated in published studies including, but not limited to, the TRIBE (TRIplet plus BEvacizumab) trial. To assess the clinical efficacy of FOLFOXIRI-Bev, including outcomes and rates of surgical conversions. A systematic review was conducted in October 2016 in concordance with the PRISMA guidelines of PubMed, the Cochrane Central Register of Controlled Trials, SCOPUS, Web of Science, Google Scholar, CINAHL, Ovid, and EMBASE using the terms FOLFOXIRI and bevacizumab and (colorectal cancer). Clinical trials, retrospective case series, and prospective case series that used FOLFOXIRI-Bev for the treatment of initially unresectable metastatic colorectal cancer in humans were included. Individual case reports and retrospective case series with fewer than 10 patients were excluded. Data were extracted independently by 2 reviewers on a predesigned, standardized form. Ultimately, data were aggregated to obtain the pooled effect size of efficacy, according to the random-effects model and weighted for the number of patients included in each trial. Median overall survival and progression-free survival, overall response rates, and rates of R0 surgical conversions and overall surgical conversions. Eleven FOLFOXIRI-Bev studies published between 2010 and 2016 met the inclusion criteria and were pooled for analysis. The studies included 889 patients, with 877 patients clinically evaluable for overall response rates. The objective response rate to FOLFOXIRI-Bev was 69% (95% CI, 65%-72%; I2 = 25%). The rate of overall surgical conversions was 39.1% (95% CI, 26.9%-52.8%), and the rate of R0 surgical conversions was 28.1% (95% CI, 18.1%-40.8%). Median pooled overall survival was 30.2 months (95% CI, 26.5-33.7 months) in 6 trials with data available, and progression-free survival was 12.4 months (95% CI, 10.0-14.3 months) in 9 trials with data available. In meta-regression analysis, variables significantly associated with conversion surgery were disease limited to the liver and a higher median number of cycles (close to 12). For patients with surgically unresectable metastatic colorectal cancer, FOLFOXIRI-Bev is associated with a significant overall response rate. Such an effective regimen leads to a probability of surgical conversion of distant metastases approaching 40%, with more than one-fourth of patients having an R0 resection.

Individual payments as a longer-term incentive in online panels.

PubMed

Göritz, Anja S; Wolff, Hans-Georg; Goldstein, Daniel G

2008-11-01

Does it pay to pay online panel members? A three-wave longitudinal experiment was conducted with an online panel to examine whether per person payments, paid through an online intermediary, influence response and retention rates. In the payment condition, participants were promised payment for participation at each wave, whereas control participants were not offered any payment. The promise of a payment had a negative effect on response in Wave 1, but a positive effect on response in Wave 2. Payment had no significant effect on retention. Completing a given wave was an indicator for responding to a subsequent invitation.

Effect of aerobic fitness on the physiological stress responses at work.

PubMed

Ritvanen, Tiina; Louhevaara, Veikko; Helin, Pertti; Halonen, Toivo; Hänninen, Osmo

2007-01-01

The aim of the present study was to examine the effects of aerobic fitness on physiological stress responses experienced by teachers during working hours. Twenty-six healthy female and male teachers aged 33-62 years participated in the study. The ratings of perceived stress visual analogue scale (VAS), and the measurement of physiological responses (norepinephrine, epinephrine, cortisol, diastolic and systolic blood pressure, heart rate (HR), and trapezius muscle activity by electromyography (EMG), were determined. Predicted maximal oxygen uptake (VO(2)max) was measured using the submaximal bicycle ergometer test. The predicted VO(2)max was standardized for age using residuals of linear regression analyses. Static EMG activity, HR and VAS were associated with aerobic fitness in teachers. The results suggest that a higher level of aerobic fitness may reduce muscle tension, HR and perceived work stress in teachers.

Investigating the Consequences of Interference between Multiple CD8+ T Cell Escape Mutations in Early HIV Infection

PubMed Central

Garcia, Victor; Feldman, Marcus W.; Regoes, Roland R.

2016-01-01

During early human immunodeficiency virus (HIV) infection multiple CD8+ T cell responses are elicited almost simultaneously. These responses exert strong selective pressures on different parts of HIV’s genome, and select for mutations that escape recognition and are thus beneficial to the virus. Some studies reveal that the later these escape mutations emerge, the more slowly they go to fixation. This pattern of escape rate decrease(ERD) can arise by distinct mechanisms. In particular, in large populations with high beneficial mutation rates interference among different escape strains –an effect that can emerge in evolution with asexual reproduction and results in delayed fixation times of beneficial mutations compared to sexual reproduction– could significantly impact the escape rates of mutations. In this paper, we investigated how interference between these concurrent escape mutations affects their escape rates in systems with multiple epitopes, and whether it could be a source of the ERD pattern. To address these issues, we developed a multilocus Wright-Fisher model of HIV dynamics with selection, mutation and recombination, serving as a null-model for interference. We also derived an interference-free null model assuming initial neutral evolution before immune response elicitation. We found that interference between several equally selectively advantageous mutations can generate the observed ERD pattern. We also found that the number of loci, as well as recombination rates substantially affect ERD. These effects can be explained by the underexponential decline of escape rates over time. Lastly, we found that the observed ERD pattern in HIV infected individuals is consistent with both independent, interference-free mutations as well as interference effects. Our results confirm that interference effects should be considered when analyzing HIV escape mutations. The challenge in estimating escape rates and mutation-associated selective coefficients posed by interference effects cannot simply be overcome by improved sampling frequencies or sizes. This problem is a consequence of the fundamental shortcomings of current estimation techniques under interference regimes. Hence, accounting for the stochastic nature of competition between mutations demands novel estimation methodologies based on the analysis of HIV strains, rather than mutation frequencies. PMID:26829720

The joy of heartfelt music: An examination of emotional and physiological responses.

PubMed

Lynar, Emily; Cvejic, Erin; Schubert, Emery; Vollmer-Conna, Ute

2017-10-01

Music-listening can be a powerful therapeutic tool for mood rehabilitation, yet quality evidence for its validity as a singular treatment is scarce. Specifically, the relationship between music-induced mood improvement and meaningful physiological change, as well as the influence of music- and person-related covariates on these outcomes are yet to be comprehensively explored. Ninety-four healthy participants completed questionnaires probing demographics, personal information, and musical background. Participants listened to two prescribed musical pieces (one classical, one jazz), an "uplifting" piece of their own choice, and an acoustic control stimulus (white noise) in randomised order. Physiological responses (heart rate, respiration, galvanic skin response) were recorded throughout. After each piece, participants rated their subjective responses on a series of Likert scales. Subjectively, the self-selected pieces induced the most joy, and the classical piece was perceived as most relaxing, consistent with the arousal ratings proposed by a music selection panel. These two stimuli led to the greatest overall improvement in composite emotional state from baseline. Psycho-physiologically, self-selected pieces often elicited a "eustress" response ("positive arousal"), whereas classical music was associated with the highest heart rate variability. Very few person-related covariates appeared to affect responses, and music-related covariates (besides self-selection) appeared arbitrary. These data provide strong evidence that optimal music for therapy varies between individuals. Our findings additionally suggest that the self-selected music was most effective for inducing a joyous state; while low arousal classical music was most likely to shift the participant into a state of relaxation. Therapy should attempt to find the most effective and "heartfelt" music for each listener, according to therapeutic goals. Copyright © 2017 Elsevier B.V. All rights reserved.

Using perceptual cues for brake response to a lead vehicle: Comparing threshold and accumulator models of visual looming.

PubMed

Xue, Qingwan; Markkula, Gustav; Yan, Xuedong; Merat, Natasha

2018-06-18

Previous studies have shown the effect of a lead vehicle's speed, deceleration rate and headway distance on drivers' brake response times. However, how drivers perceive this information and use it to determine when to apply braking is still not quite clear. To better understand the underlying mechanisms, a driving simulator experiment was performed where each participant experienced nine deceleration scenarios. Previously reported effects of the lead vehicle's speed, deceleration rate and headway distance on brake response time were firstly verified in this paper, using a multilevel model. Then, as an alternative to measures of speed, deceleration rate and distance, two visual looming-based metrics (angular expansion rate θ˙ of the lead vehicle on the driver's retina, and inverse tau τ -1 , the ratio between θ˙ and the optical size θ), considered to be more in line with typical human psycho-perceptual responses, were adopted to quantify situation urgency. These metrics were used in two previously proposed mechanistic models predicting brake onset: either when looming surpasses a threshold, or when the accumulated evidence (looming and other cues) reaches a threshold. Results showed that the looming threshold model did not capture the distribution of brake response time. However, regardless of looming metric, the accumulator models fitted the distribution of brake response times better than the pure threshold models. Accumulator models, including brake lights, provided a better model fit than looming-only versions. For all versions of the mechanistic models, models using τ -1 as the measure of looming fitted better than those using θ˙, indicating that the visual cues drivers used during rear-end collision avoidance may be more close to τ -1 . Copyright © 2018 Elsevier Ltd. All rights reserved.

Orthostatic Hypotension and Elevated Resting Heart Rate Predict Low-Energy Fractures in the Population: The Malmö Preventive Project.

PubMed

Hamrefors, Viktor; Härstedt, Maria; Holmberg, Anna; Rogmark, Cecilia; Sutton, Richard; Melander, Olle; Fedorowski, Artur

2016-01-01

Autonomic disorders of the cardiovascular system, such as orthostatic hypotension and elevated resting heart rate, predict mortality and cardiovascular events in the population. Low-energy-fractures constitute a substantial clinical problem that may represent an additional risk related to such autonomic dysfunction. To test the association between orthostatic hypotension, resting heart rate and incidence of low-energy-fractures in the general population. Using multivariable-adjusted Cox regression models we investigated the association between orthostatic blood pressure response, resting heart rate and first incident low-energy-fracture in a population-based, middle-aged cohort of 33 000 individuals over 25 years follow-up. The median follow-up time from baseline to first incident fracture among the subjects that experienced a low energy fracture was 15.0 years. A 10 mmHg orthostatic decrease in systolic blood pressure at baseline was associated with 5% increased risk of low-energy-fractures (95% confidence interval 1.01-1.10) during follow-up, whereas the resting heart rate predicted low-energy-fractures with an effect size of 8% increased risk per 10 beats-per-minute (1.05-1.12), independently of the orthostatic response. Subjects with a resting heart rate exceeding 68 beats-per-minute had 18% (1.10-1.26) increased risk of low-energy-fractures during follow-up compared with subjects with a resting heart rate below 68 beats-per-minute. When combining the orthostatic response and resting heart rate, there was a 30% risk increase (1.08-1.57) of low-energy-fractures between the extremes, i.e. between subjects in the fourth compared with the first quartiles of both resting heart rate and systolic blood pressure-decrease. Orthostatic blood pressure decline and elevated resting heart rate independently predict low-energy fractures in a middle-aged population. These two measures of subclinical cardiovascular dysautonomia may herald increased risks many years in advance, even if symptoms may not be detectable. Although the effect sizes are moderate, the easily accessible clinical parameters of orthostatic blood pressure response and resting heart rate deserve consideration as new risk predictors to yield more accurate decisions on primary prevention of low-energy fractures.