Observing Behavior and Atypically Restricted Stimulus Control

ERIC Educational Resources Information Center

Dube, William V.; Dickson, Chata A.; Balsamo, Lyn M.; O'Donnell, Kristin Lombard; Tomanari, Gerson Y.; Farren, Kevin M.; Wheeler, Emily E.; McIlvane, William J.

2010-01-01

Restricted stimulus control refers to discrimination learning with atypical limitations in the range of controlling stimuli or stimulus features. In the study reported here, 4 normally capable individuals and 10 individuals with intellectual disabilities (ID) performed two-sample delayed matching to sample. Sample-stimulus observing was recorded…

Observability of Boolean multiplex control networks

NASA Astrophysics Data System (ADS)

Wu, Yuhu; Xu, Jingxue; Sun, Xi-Ming; Wang, Wei

2017-04-01

Boolean multiplex (multilevel) networks (BMNs) are currently receiving considerable attention as theoretical arguments for modeling of biological systems and system level analysis. Studying control-related problems in BMNs may not only provide new views into the intrinsic control in complex biological systems, but also enable us to develop a method for manipulating biological systems using exogenous inputs. In this article, the observability of the Boolean multiplex control networks (BMCNs) are studied. First, the dynamical model and structure of BMCNs with control inputs and outputs are constructed. By using of Semi-Tensor Product (STP) approach, the logical dynamics of BMCNs is converted into an equivalent algebraic representation. Then, the observability of the BMCNs with two different kinds of control inputs is investigated by giving necessary and sufficient conditions. Finally, examples are given to illustrate the efficiency of the obtained theoretical results.

Vitamin C Intake and Pancreatic Cancer Risk: A Meta-Analysis of Published Case-Control and Cohort Studies.

PubMed

Hua, Yong-Fei; Wang, Gao-Qing; Jiang, Wei; Huang, Jing; Chen, Guo-Chong; Lu, Cai-De

2016-01-01

Observational studies inconsistently reported the relationship between vitamin C intake and risk of pancreatic cancer. We conducted a meta-analysis of published case-control and cohort studies to quantify the association. Potentially eligible studies were found on PubMed and EMBASE databases through May 31, 2015. A random-effects model was assigned to compute summary point estimates with corresponding 95% confidence intervals (CIs). Subgroup and meta-regression analyses were also performed to explore sources of heterogeneity. Our final analyses included 20 observational studies comprising nearly 5 thousand cases of pancreatic cancer. When comparing the highest with the lowest categories of vitamin C intake, the summary odds ratio/relative risk for case-control studies (14 studies), cohort studies (6 studies) and all studies combined was 0.58 (95% CI: 0.52-0.66), 0.93 (95% CI: 0.78-1.11) and 0.66 (95% CI: 0.58-0.75), respectively. The difference in the findings between case-control and cohort studies was statistically significant (P < .001). Possible publication bias was shown in the meta-analysis of case-control studies. There is insufficient evidence to conclude any relationship between vitamin C intake and risk of pancreatic cancer. The strong inverse association observed in case-control studies may be affected by biases (eg, recall and selection biases) that particularly affect case-control studies and/or potential publication bias. Future prospective studies of vitamin C intake and pancreatic cancer are needed.

Voluntarily controlled but not merely observed visual feedback affects postural sway

PubMed Central

Asai, Tomohisa; Hiromitsu, Kentaro; Imamizu, Hiroshi

2018-01-01

Online stabilization of human standing posture utilizes multisensory afferences (e.g., vision). Whereas visual feedback of spontaneous postural sway can stabilize postural control especially when observers concentrate on their body and intend to minimize postural sway, the effect of intentional control of visual feedback on postural sway itself remains unclear. This study assessed quiet standing posture in healthy adults voluntarily controlling or merely observing visual feedback. The visual feedback (moving square) had either low or high gain and was either horizontally flipped or not. Participants in the voluntary-control group were instructed to minimize their postural sway while voluntarily controlling visual feedback, whereas those in the observation group were instructed to minimize their postural sway while merely observing visual feedback. As a result, magnified and flipped visual feedback increased postural sway only in the voluntary-control group. Furthermore, regardless of the instructions and feedback manipulations, the experienced sense of control over visual feedback positively correlated with the magnitude of postural sway. We suggest that voluntarily controlled, but not merely observed, visual feedback is incorporated into the feedback control system for posture and begins to affect postural sway. PMID:29682421

Strategies in probabilistic feedback learning in Parkinson patients OFF medication.

PubMed

Bellebaum, C; Kobza, S; Ferrea, S; Schnitzler, A; Pollok, B; Südmeyer, M

2016-04-21

Studies on classification learning suggested that altered dopamine function in Parkinson's Disease (PD) specifically affects learning from feedback. In patients OFF medication, enhanced learning from negative feedback has been described. This learning bias was not seen in observational learning from feedback, indicating different neural mechanisms for this type of learning. The present study aimed to compare the acquisition of stimulus-response-outcome associations in PD patients OFF medication and healthy control subjects in active and observational learning. 16 PD patients OFF medication and 16 controls were examined with three parallel learning tasks each, two feedback-based (active and observational) and one non-feedback-based paired associates task. No acquisition deficit was seen in the patients for any of the tasks. More detailed analyses on the learning strategies did, however, reveal that the patients showed more lose-shift responses during active feedback learning than controls, and that lose-shift and win-stay responses more strongly determined performance accuracy in patients than controls. For observational feedback learning, the performance of both groups correlated similarly with the performance in non-feedback-based paired associates learning and with the accuracy of observed performance. Also, patients and controls showed comparable evidence of feedback processing in observational learning. In active feedback learning, PD patients use alternative learning strategies than healthy controls. Analyses on observational learning did not yield differences between patients and controls, adding to recent evidence of a differential role of the human striatum in active and observational learning from feedback. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Income, neural executive processes, and preschool children's executive control.

PubMed

Ruberry, Erika J; Lengua, Liliana J; Crocker, Leanna Harris; Bruce, Jacqueline; Upshaw, Michaela B; Sommerville, Jessica A

2017-02-01

This study aimed to specify the neural mechanisms underlying the link between low household income and diminished executive control in the preschool period. Specifically, we examined whether individual differences in the neural processes associated with executive attention and inhibitory control accounted for income differences observed in performance on a neuropsychological battery of executive control tasks. The study utilized a sample of preschool-aged children (N = 118) whose families represented the full range of income, with 32% of families at/near poverty, 32% lower income, and 36% middle to upper income. Children completed a neuropsychological battery of executive control tasks and then completed two computerized executive control tasks while EEG data were collected. We predicted that differences in the event-related potential (ERP) correlates of executive attention and inhibitory control would account for income differences observed on the executive control battery. Income and ERP measures were related to performance on the executive control battery. However, income was unrelated to ERP measures. The findings suggest that income differences observed in executive control during the preschool period might relate to processes other than executive attention and inhibitory control.

The Importance of Covariate Selection in Controlling for Selection Bias in Observational Studies

ERIC Educational Resources Information Center

Steiner, Peter M.; Cook, Thomas D.; Shadish, William R.; Clark, M. H.

2010-01-01

The assumption of strongly ignorable treatment assignment is required for eliminating selection bias in observational studies. To meet this assumption, researchers often rely on a strategy of selecting covariates that they think will control for selection bias. Theory indicates that the most important covariates are those highly correlated with…

Case-control Studies on the Effectiveness of Breast Cancer Screening: Insights from the UK Age Trial.

PubMed

van der Waal, Daniëlle; Broeders, Mireille J M; Verbeek, André L M; Duffy, Stephen W; Moss, Sue M

2015-07-01

Ongoing breast cancer screening programs can only be evaluated using observational study designs. Most studies have observed a reduction in breast cancer mortality, but design differences appear to have resulted in different estimates. Direct comparison of case-control and trial analyses gives more insight into this variation. Here, we performed case-control analyses within the randomized UK Age Trial. The Age Trial assessed the effect of screening on breast cancer mortality in women ages 40-49 years. In our approach, case subjects were defined as breast cancer deaths between trial entry (1991-1997) and 2004. Women were ages 39-41 years at entry. For every case subject, five control subjects were selected. All case subjects were included in analyses of screening invitation (356 case subjects, 1,780 controls), whereas analyses of attendance were restricted to women invited to screening (105 case subjects, 525 age-matched controls). Odds ratios (OR) were estimated with conditional logistic regression. We used and compared two methods to correct for self-selection bias. Screening invitation resulted in a breast cancer mortality reduction of 17% (95% confidence interval [CI]: -36%, +6%), similar to trial results. Different exposure definitions and self-selection adjustments influenced the observed breast cancer mortality reduction. Depending on the method, "ever screened" appeared to be associated with a small reduction (OR: 0.86, 95% CI: 0.40, 1.89) or no reduction (OR: 1.02, 95% CI: 0.48, 2.14) using the two methods of correction. Recent attendance resulted in an adjusted mortality reduction of 36% (95% CI: -69%, +31%) or 45% (95% CI: -71%, +5%). Observational studies, and particularly case-control studies, are an important monitoring tool for breast cancer screening programs. The focus should be on diminishing bias in observational studies and gaining a better understanding of the influence of study design on estimates of mortality reduction.

Ways of learning: Observational studies versus experiments

USGS Publications Warehouse

Shaffer, T.L.; Johnson, D.H.

2008-01-01

Manipulative experimentation that features random assignment of treatments, replication, and controls is an effective way to determine causal relationships. Wildlife ecologists, however, often must take a more passive approach to investigating causality. Their observational studies lack one or more of the 3 cornerstones of experimentation: controls, randomization, and replication. Although an observational study can be analyzed similarly to an experiment, one is less certain that the presumed treatment actually caused the observed response. Because the investigator does not actively manipulate the system, the chance that something other than the treatment caused the observed results is increased. We reviewed observational studies and contrasted them with experiments and, to a lesser extent, sample surveys. We identified features that distinguish each method of learning and illustrate or discuss some complications that may arise when analyzing results of observational studies. Findings from observational studies are prone to bias. Investigators can reduce the chance of reaching erroneous conclusions by formulating a priori hypotheses that can be pursued multiple ways and by evaluating the sensitivity of study conclusions to biases of various magnitudes. In the end, however, professional judgment that considers all available evidence is necessary to render a decision regarding causality based on observational studies.

Reserpine in weight reduction. The effect in obese patients on 1,000-calorie diets: a controlled study.

PubMed

SMITH, M C

1959-10-01

In a controlled study (the control group receiving pyribenzamine) it was observed that reserpine, in the dosage used, had no effect on weight loss in patients receiving d-amphetamine sulphate (Dexedrine(R)) and methyl cellulose (Cellothyl(R)) while on 1,000-calorie diets as compared with the control group. There was no observable difference in subjective feelings of the patients in the two groups. Reserpine had no effect on the length of time the patients remained on their diets.

RESERPINE IN WEIGHT REDUCTION—The Effect in Obese Patients on 1,000-Calorie Diets: A Controlled Study

PubMed Central

Smith, Maurice C.

1959-01-01

In a controlled study (the control group receiving pyribenzamine) it was observed that reserpine, in the dosage used, had no effect on weight loss in patients receiving d-amphetamine sulphate (Dexedrine®) and methyl cellulose (Cellothyl®) while on 1,000-calorie diets as compared with the control group. There was no observable difference in subjective feelings of the patients in the two groups. Reserpine had no effect on the length of time the patients remained on their diets. PMID:13832087

Knowledge translation interventions for critically ill patients: a systematic review*.

PubMed

Sinuff, Tasnim; Muscedere, John; Adhikari, Neill K J; Stelfox, Henry T; Dodek, Peter; Heyland, Daren K; Rubenfeld, Gordon D; Cook, Deborah J; Pinto, Ruxandra; Manoharan, Venika; Currie, Jan; Cahill, Naomi; Friedrich, Jan O; Amaral, Andre; Piquette, Dominique; Scales, Damon C; Dhanani, Sonny; Garland, Allan

2013-11-01

We systematically reviewed ICU-based knowledge translation studies to assess the impact of knowledge translation interventions on processes and outcomes of care. We searched electronic databases (to July, 2010) without language restrictions and hand-searched reference lists of relevant studies and reviews. Two reviewers independently identified randomized controlled trials and observational studies comparing any ICU-based knowledge translation intervention (e.g., protocols, guidelines, and audit and feedback) to management without a knowledge translation intervention. We focused on clinical topics that were addressed in greater than or equal to five studies. Pairs of reviewers abstracted data on the clinical topic, knowledge translation intervention(s), process of care measures, and patient outcomes. For each individual or combination of knowledge translation intervention(s) addressed in greater than or equal to three studies, we summarized each study using median risk ratio for dichotomous and standardized mean difference for continuous process measures. We used random-effects models. Anticipating a small number of randomized controlled trials, our primary meta-analyses included randomized controlled trials and observational studies. In separate sensitivity analyses, we excluded randomized controlled trials and collapsed protocols, guidelines, and bundles into one category of intervention. We conducted meta-analyses for clinical outcomes (ICU and hospital mortality, ventilator-associated pneumonia, duration of mechanical ventilation, and ICU length of stay) related to interventions that were associated with improvements in processes of care. From 11,742 publications, we included 119 investigations (seven randomized controlled trials, 112 observational studies) on nine clinical topics. Interventions that included protocols with or without education improved continuous process measures (seven observational studies and one randomized controlled trial; standardized mean difference [95% CI]: 0.26 [0.1, 0.42]; p = 0.001 and four observational studies and one randomized controlled trial; 0.83 [0.37, 1.29]; p = 0.0004, respectively). Heterogeneity among studies within topics ranged from low to extreme. The exclusion of randomized controlled trials did not change our results. Single-intervention and lower-quality studies had higher standardized mean differences compared to multiple-intervention and higher-quality studies (p = 0.013 and 0.016, respectively). There were no associated improvements in clinical outcomes. Knowledge translation interventions in the ICU that include protocols with or without education are associated with the greatest improvements in processes of critical care.

[Realization of design regarding experimental research in the clinical real-world research].

PubMed

He, Q; Shi, J P

2018-04-10

Real world study (RWS), a further verification and supplement for explanatory randomized controlled trial to evaluate the effectiveness of intervention measures in real clinical environment, has increasingly become the focus in the field of research on medical and health care services. However, some people mistakenly equate real world study with observational research, and argue that intervention and randomization cannot be carried out in real world study. In fact, both observational and experimental design are the basic designs in real world study, while the latter usually refers to pragmatic randomized controlled trial and registry-based randomized controlled trial. Other nonrandomized controlled and adaptive designs can also be adopted in the RWS.

? observer-based decentralised fuzzy control design for nonlinear interconnected systems: an application to vehicle dynamics

NASA Astrophysics Data System (ADS)

Latrach, Chedia; Kchaou, Mourad; Guéguen, Hervé

2017-05-01

In this study, a decentralised output learning control strategy for a class of nonlinear interconnected systems is studied. Based on Takagi-Sugeno fuzzy (TS) model to approximate the considered interconnected nonlinear systems, a decentralised observer-based control scheme is designed to override the external disturbances such that the ? performance is achieved. The appealing attributes of this approach include: (1) the closed-loop system exhibits a robustness against nonlinear interconnections and external disturbance, (2) by one-step procedure, the gain matrices of observer and controller are obtained on a single step. In simulation results, the controller design is evaluated on the steering stability of a car where the nonlinear model describes the side slip, roll and yaw motions of the automotive vehicle equipped with four-wheel-steering and active suspension.

Sonographic Alteration of Basal Ganglia in Different Forms of Primary Focal Dystonia: A Cross-sectional Study

PubMed Central

Zhang, Ying; Zhang, Ying-Chun; Sheng, Yu-Jing; Chen, Xiao-Fang; Wang, Cai-Shan; Ma, Qi; Chen, Han-Bing; Yu, Li-Fang; Mao, Cheng-Jie; Xiong, Kang-Ping; Luo, Wei-Feng; Liu, Chun-Feng

2016-01-01

Background: Few studies have addressed whether abnormalities in the lenticular nucleus (LN) are characteristic transcranial sonography (TCS) echo features in patients with primary dystonia. This study aimed to explore alterations in the basal ganglia in different forms of primary focal dystonia. Methods: cross-sectional observational study was performed between December 2013 and December 2014 in 80 patients with different forms of primary focal dystonia and 55 neurologically normal control subjects. TCS was performed in patients and control subjects. Multiple comparisons of multiple rates were used to compare LN hyperechogenicity ratios between control and patient groups. Results: Thirteen individuals were excluded due to poor temporal bone windows, and two subjects were excluded due to disagreement in evaluation by sonologists. Totally, 70 patients (cervical dystonia, n = 30; blepharospasm, n = 30; oromandibular dystonia, n = 10) and 50 normal controls were included in the final analysis. LN hyperechogenicity was observed in 51% (36/70) of patients with primary focal dystonia, compared with 12% (6/50) of controls (P < 0.001). Substantia nigra hyperechogenicity did not differ between the two groups. LN hyperechogenicity was observed in 73% (22/30) of patients with cervical dystonia, a greater prevalence than in patients with blepharospasm (33%, 10/30, P = 0.002) and oromandibular dystonia (40%, 4/10, P = 0.126). LN hyperechogenicity was more frequently observed in patients with cervical dystonia compared with controls (73% vs. 12%, P < 0.001); however, no significant difference was detected in patients with blepharospasm (33% vs. 12%, P = 0.021) or oromandibular dystonia (40% vs. 12%, P = 0.088). Conclusions: LN hyperechogenicity is more frequently observed in patients with primary focal dystonia than in controls. It does not appear to be a characteristic TCS echo feature in patients with blepharospasm or oromandibular dystonia. PMID:27064039

Executive Control Goes to School: Implications of Preschool Executive Performance for Observed Elementary Classroom Learning Engagement

ERIC Educational Resources Information Center

Nelson, Timothy D.; Nelson, Jennifer Mize; James, Tiffany D.; Clark, Caron A. C.; Kidwell, Katherine M.; Espy, Kimberly Andrews

2017-01-01

The transition to elementary school is accompanied by increasing demands for children to regulate their attention and behavior within the classroom setting. Executive control (EC) may be critical for meeting these demands; however, few studies have rigorously examined the association between EC and observed classroom behavior. This study examined…

Metacognitive monitoring and control in visual change detection: Implications for situation awareness and cognitive control

PubMed Central

McAnally, Ken I.; Morris, Adam P.; Best, Christopher

2017-01-01

Metacognitive monitoring and control of situation awareness (SA) are important for a range of safety-critical roles (e.g., air traffic control, military command and control). We examined the factors affecting these processes using a visual change detection task that included representative tactical displays. SA was assessed by asking novice observers to detect changes to a tactical display. Metacognitive monitoring was assessed by asking observers to estimate the probability that they would correctly detect a change, either after study of the display and before the change (judgement of learning; JOL) or after the change and detection response (judgement of performance; JOP). In Experiment 1, observers failed to detect some changes to the display, indicating imperfect SA, but JOPs were reasonably well calibrated to objective performance. Experiment 2 examined JOLs and JOPs in two task contexts: with study-time limits imposed by the task or with self-pacing to meet specified performance targets. JOPs were well calibrated in both conditions as were JOLs for high performance targets. In summary, observers had limited SA, but good insight about their performance and learning for high performance targets and allocated study time appropriately. PMID:28915244

The effectiveness of the mumps component of the MMR vaccine: a case control study.

PubMed

Harling, Richard; White, Joanne M; Ramsay, Mary E; Macsween, Karen F; van den Bosch, Corry

2005-07-01

In 1998/1999, an outbreak of mumps occurred among children of a religious community in North East London. A case control study was conducted to assess the effectiveness of the mumps component of the MMR vaccine. One hundred and sixty-one cases of mumps were identified and 192 controls were selected. Fifty-one percent of cases and 77% of controls had a history at least one MMR vaccination. The observed effectiveness of any MMR vaccination adjusted for age, sex and general practice was 69% (95% CI: 41-84%). This is consistent with the results of other observational studies of mumps containing vaccines, but lower than the immunogenicity of mumps vaccines reported by clinical trials. This discrepancy is because observational studies tend to underestimate vaccine effectiveness, and because immunogenicity is not necessarily an accurate biological marker of vaccine effectiveness. Two doses of vaccine were more effective (88% (95% CI: 62-96%)) than a single dose (64% (95% CI: 40-78%)). The current two-dose vaccination programme remains the best method for controlling mumps infection in the community.

Assessing validity of observational intervention studies - the Benchmarking Controlled Trials.

PubMed

Malmivaara, Antti

2016-09-01

Benchmarking Controlled Trial (BCT) is a concept which covers all observational studies aiming to assess impact of interventions or health care system features to patients and populations. To create and pilot test a checklist for appraising methodological validity of a BCT. The checklist was created by extracting the most essential elements from the comprehensive set of criteria in the previous paper on BCTs. Also checklists and scientific papers on observational studies and respective systematic reviews were utilized. Ten BCTs published in the Lancet and in the New England Journal of Medicine were used to assess feasibility of the created checklist. The appraised studies seem to have several methodological limitations, some of which could be avoided in planning, conducting and reporting phases of the studies. The checklist can be used for planning, conducting, reporting, reviewing, and critical reading of observational intervention studies. However, the piloted checklist should be validated in further studies. Key messages Benchmarking Controlled Trial (BCT) is a concept which covers all observational studies aiming to assess impact of interventions or health care system features to patients and populations. This paper presents a checklist for appraising methodological validity of BCTs and pilot-tests the checklist with ten BCTs published in leading medical journals. The appraised studies seem to have several methodological limitations, some of which could be avoided in planning, conducting and reporting phases of the studies. The checklist can be used for planning, conducting, reporting, reviewing, and critical reading of observational intervention studies.

Quasi-minimal active disturbance rejection control of MIMO perturbed linear systems based on differential neural networks and the attractive ellipsoid method.

PubMed

Salgado, Iván; Mera-Hernández, Manuel; Chairez, Isaac

2017-11-01

This study addresses the problem of designing an output-based controller to stabilize multi-input multi-output (MIMO) systems in the presence of parametric disturbances as well as uncertainties in the state model and output noise measurements. The controller design includes a linear state transformation which separates uncertainties matched to the control input and the unmatched ones. A differential neural network (DNN) observer produces a nonlinear approximation of the matched perturbation and the unknown states simultaneously in the transformed coordinates. This study proposes the use of the Attractive Ellipsoid Method (AEM) to optimize the gains of the controller and the gain observer in the DNN structure. As a consequence, the obtained control input minimizes the convergence zone for the estimation error. Moreover, the control design uses the estimated disturbance provided by the DNN to obtain a better performance in the stabilization task in comparison with a quasi-minimal output feedback controller based on a Luenberger observer and a sliding mode controller. Numerical results pointed out the advantages obtained by the nonlinear control based on the DNN observer. The first example deals with the stabilization of an academic linear MIMO perturbed system and the second example stabilizes the trajectories of a DC-motor into a predefined operation point. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

An observation tool to study air traffic control and flightdeck collaboration.

PubMed

Cox, Gemma; Sharples, Sarah; Stedmon, Alex; Wilson, John

2007-07-01

The complex systems of the flightdeck (FD) and the Air Traffic Control Centre (ATC) are characterised by numerous concurrently operating and interacting communication channels between people and between people and machines/computer systems. This paper describes work in support of investigating the impact of changes to technologies and responsibilities within this system with respect to human factors. It focuses primarily on the introduction of datalink (text-based communication rather than traditional radio communication) and the move towards freeflight (pilot-mediated air traffic control). Air traffic management investigations have outlined these specific changes as strategies to enable further increases in the volume of air traffic. A systems approach was taken and field studies were conducted. Small numbers of domain experts such as air traffic controllers (ATCOs) were involved in the field-based observations of how people interact with systems and each other. This paper summarises the overall research approach taken and then specifically reports on the field-based observations including the justification, development, and findings of the observation tool used. The observation tool examined information propagation through the air traffic control-flightdeck (ATC-FD) system, and resulted in models of possible information trajectories through the system.

Squeezing observational data for better causal inference: Methods and examples for prevention research.

PubMed

Garcia-Huidobro, Diego; Michael Oakes, J

2017-04-01

Randomised controlled trials (RCTs) are typically viewed as the gold standard for causal inference. This is because effects of interest can be identified with the fewest assumptions, especially imbalance in background characteristics. Yet because conducting RCTs are expensive, time consuming and sometimes unethical, observational studies are frequently used to study causal associations. In these studies, imbalance, or confounding, is usually controlled with multiple regression, which entails strong assumptions. The purpose of this manuscript is to describe strengths and weaknesses of several methods to control for confounding in observational studies, and to demonstrate their use in cross-sectional dataset that use patient registration data from the Juan Pablo II Primary Care Clinic in La Pintana-Chile. The dataset contains responses from 5855 families who provided complete information on family socio-demographics, family functioning and health problems among their family members. We employ regression adjustment, stratification, restriction, matching, propensity score matching, standardisation and inverse probability weighting to illustrate the approaches to better causal inference in non-experimental data and compare results. By applying study design and data analysis techniques that control for confounding in different ways than regression adjustment, researchers may strengthen the scientific relevance of observational studies. © 2016 International Union of Psychological Science.

The Effects of Religion and Locus of Control on Perception of Mental Illness.

PubMed

Amedome, Sedem Nunyuia; Bedi, Innocent Kwame

2018-06-23

The study investigated the influence of religion and locus of control on perception of mental illness. Specifically, the study explored the relationship between religiosity and perception of mental illness, differences in perception by internals and externals, the effect of knowledge on perception of mental illness and the interactive effect of religiosity and locus of control on perception of mental illness. Data were collected from 200 participants in the Volta Region of Ghana. Three hypotheses were tested in the study using a battery of tests. It was observed that people with internal locus of control perceive mental patients positively than those with external locus of control. A significant interactive effect between religiosity and locus of control on perception of mental illness was observed. Religiosity significantly relates to perception of mental illness. The results and implications are discussed for further studies.

Dipeptidyl peptidase-4 inhibitors and risk of heart failure in type 2 diabetes: systematic review and meta-analysis of randomised and observational studies.

PubMed

Li, Ling; Li, Sheyu; Deng, Ke; Liu, Jiali; Vandvik, Per Olav; Zhao, Pujing; Zhang, Longhao; Shen, Jiantong; Bala, Malgorzata M; Sohani, Zahra N; Wong, Evelyn; Busse, Jason W; Ebrahim, Shanil; Malaga, German; Rios, Lorena P; Wang, Yingqiang; Chen, Qunfei; Guyatt, Gordon H; Sun, Xin

2016-02-17

To examine the association between dipeptidyl peptidase-4 (DPP-4) inhibitors and the risk of heart failure or hospital admission for heart failure in patients with type 2 diabetes. Systematic review and meta-analysis of randomised and observational studies. Medline, Embase, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov searched up to 25 June 2015, and communication with experts. Randomised controlled trials, non-randomised controlled trials, cohort studies, and case-control studies that compared DPP-4 inhibitors against placebo, lifestyle modification, or active antidiabetic drugs in adults with type 2 diabetes, and explicitly reported the outcome of heart failure or hospital admission for heart failure. Teams of paired reviewers independently screened for eligible studies, assessed risk of bias, and extracted data using standardised, pilot tested forms. Data from trials and observational studies were pooled separately; quality of evidence was assessed by the GRADE approach. Eligible studies included 43 trials (n=68,775) and 12 observational studies (nine cohort studies, three nested case-control studies; n=1,777,358). Pooling of 38 trials reporting heart failure provided low quality evidence for a possible similar risk of heart failure between DPP-4 inhibitor use versus control (42/15,701 v 33/12,591; odds ratio 0.97 (95% confidence interval 0.61 to 1.56); risk difference 2 fewer (19 fewer to 28 more) events per 1000 patients with type 2 diabetes over five years). The observational studies provided effect estimates generally consistent with trial findings, but with very low quality evidence. Pooling of the five trials reporting admission for heart failure provided moderate quality evidence for an increased risk in patients treated with DPP-4 inhibitors versus control (622/18,554 v 552/18,474; 1.13 (1.00 to 1.26); 8 more (0 more to 16 more)). The pooling of adjusted estimates from observational studies similarly suggested (with very low quality evidence) a possible increased risk of admission for heart failure (adjusted odds ratio 1.41, 95% confidence interval 0.95 to 2.09) in patients treated with DPP-4 inhibitors (exclusively sitagliptin) versus no use. The relative effect of DPP-4 inhibitors on the risk of heart failure in patients with type 2 diabetes is uncertain, given the relatively short follow-up and low quality of evidence. Both randomised controlled trials and observational studies, however, suggest that these drugs may increase the risk of hospital admission for heart failure in those patients with existing cardiovascular diseases or multiple risk factors for vascular diseases, compared with no use. 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.

Full-order Luenberger observer based on fuzzy-logic control for sensorless field-oriented control of a single-sided linear induction motor.

PubMed

Holakooie, Mohammad Hosein; Ojaghi, Mansour; Taheri, Asghar

2016-01-01

This paper investigates sensorless indirect field oriented control (IFOC) of SLIM with full-order Luenberger observer. The dynamic equations of SLIM are first elaborated to draw full-order Luenberger observer with some simplifying assumption. The observer gain matrix is derived from conventional procedure so that observer poles are proportional to SLIM poles to ensure the stability of system for wide range of linear speed. The operation of observer is significantly impressed by adaptive scheme. A fuzzy logic control (FLC) is proposed as adaptive scheme to estimate linear speed using speed tuning signal. The parameters of FLC are tuned using an off-line method through chaotic optimization algorithm (COA). The performance of the proposed observer is verified by both numerical simulation and real-time hardware-in-the-loop (HIL) implementation. Moreover, a detailed comparative study among proposed and other speed observers is obtained under different operation conditions. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

Globally linearized control on diabatic continuous stirred tank reactor: a case study.

PubMed

Jana, Amiya Kumar; Samanta, Amar Nath; Ganguly, Saibal

2005-07-01

This paper focuses on the promise of globally linearized control (GLC) structure in the realm of strongly nonlinear reactor system control. The proposed nonlinear control strategy is comprised of: (i) an input-output linearizing state feedback law (transformer), (ii) a state observer, and (iii) an external linear controller. The synthesis of discrete-time GLC controller for single-input single-output diabatic continuous stirred tank reactor (DCSTR) has been studied first, followed by the synthesis of feedforward/feedback controller for the same reactor having dead time in process as well as in disturbance. Subsequently, the multivariable GLC structure has been designed and then applied on multi-input multi-output DCSTR system. The simulation study shows high quality performance of the derived nonlinear controllers. The better-performed GLC in conjunction with reduced-order observer has been compared with the conventional proportional integral controller on the example reactor and superior performance has been achieved by the proposed GLC control scheme.

The health impacts of women's low control in their living environment: A theory-based systematic review of observational studies in societies with profound gender discrimination.

PubMed

Pennington, Andy; Orton, Lois; Nayak, Shilpa; Ring, Adele; Petticrew, Mark; Sowden, Amanda; White, Martin; Whitehead, Margaret

2018-05-01

We conducted a systematic review of observational evidence on the health impacts of women's low control/autonomy in the living environment in societies with profound gender discrimination and gender bias. Thirty observational studies of varying methodological quality were included. Overall, the evidence suggests that women's lower control or autonomy (for example lack of freedom of movement outside the home, lack of authority to access healthcare for sick children) was associated with poorer mental and physical health for women and higher morbidity and mortality for their children, after adjusting for their socioeconomic circumstances. Further studies are needed to disentangle and understand the pathways between low control and health outcomes in contexts of profound gender discrimination. This systematic review has highlighted the general low quality of the evidence base on this research question. It identifies the pressing need for high quality, longitudinal studies in the future. Crown Copyright © 2018. Published by Elsevier Ltd. All rights reserved.

ACT2 peer-driven intervention increases enrollment into HIV/AIDS medical studies among African-Americans/Blacks and Hispanics: A cluster randomized controlled trial

PubMed Central

Gwadz, Marya; Cleland, Charles M.; Belkin, Mindy; Ritchie, Amanda; Leonard, Noelle; Riedel, Marion; Banfield, Angela; Colon, Pablo; Elharrar, Vanessa; Kagan, Jonathan; Mildvan, Donna

2014-01-01

African American/Black and Hispanic persons living with HIV/AIDS (“AABH-PLHA”) are under-represented in HIV/AIDS medical studies (HAMS). This paper evaluates the efficacy of a social/behavioral intervention to increase rates of screening for and enrollment into HAMS in these populations. Participants (N=540) were enrolled into a cluster randomized controlled trial of an intervention designed to overcome multi-level barriers to HAMS. Primary endpoints were rates of screening for and enrollment into therapeutic/treatment-oriented and observational studies. Intervention arm participants were 30 times more likely to be screened than controls (49.3% vs. 3.7%; p < .001). Half (55.5%) of those screened were eligible for HAMS, primarily observational studies. Nine out of ten found eligible enrolled (91.7%), almost all into observational studies (95.2%), compared to no enrollments among controls. Achieving appropriate representation of AABH-PLHA in HAMS necessitates modification of study inclusion criteria to increase the proportion found eligible for therapeutic HAMS, in addition to social/behavioral interventions. PMID:24961193

Does Helicobacter pylori infection play a role in iron deficiency anemia? A meta-analysis

PubMed Central

Qu, Xin-Hua; Huang, Xiao-Lu; Xiong, Ping; Zhu, Cui-Ying; Huang, You-Liang; Lu, Lun-Gen; Sun, Xu; Rong, Lan; Zhong, Liang; Sun, Da-Yu; Lin, Hai; Cai, Ming-Ci; Chen, Zhi-Wei; Hu, Bing; Wu, Lian-Ming; Jiang, Yi-Bin; Yan, Wei-Li

2010-01-01

AIM: To perform a meta-analysis of observational studies and randomized controlled trials (RCTs) on the association between Helicobacter pylori (H. pylori) and iron deficiency anemia (IDA). METHODS: A defined search strategy was used to search Medline, Embase, the Cochrane Library, Clinical Trials, Cochrane Central Register of Controlled Trials, Premedline and Healthstar. Odds ratio (OR) was used to evaluate observational epidemiology studies, and weighted mean difference (WMD) was used to demonstrate the difference between control and intervention groups. RESULTS: Fifteen observational studies and 5 RCTs were identified and used for calculation. The pooled OR for observational studies was 2.22 (95% CI: 1.52-3.24, P < 0.0001). The WMD for hemoglobin (HB) was 4.06 g/L (95% CI: -2.57-10.69, P = 0.01), and the WMD for serum ferritin (SF) was 9.47 μg/L (95% CI: -0.50-19.43, P < 0.0001). Results were heterogeneous for all comparisons. CONCLUSION: This meta-analysis on observational studies suggests an association between H. pylori and IDA. In RCTs, eradication of H. pylori can improve HB and SF levels but not significantly. PMID:20143469

Internal hydraulic control in the Little Belt, Denmark - observations of flow configurations and water mass formation

NASA Astrophysics Data System (ADS)

Holtegaard Nielsen, Morten; Vang, Torben; Chresten Lund-Hansen, Lars

2017-12-01

Internal hydraulic control, which occurs when stratified water masses are forced through an abrupt constriction, plays an enormous role in nature on both large and regional scales with respect to dynamics, circulation, and water mass formation. Despite a growing literature on this subject surprisingly few direct observations have been made that conclusively show the existence of and the circumstances related to internal hydraulic control in nature. In this study we present observations from the Little Belt, Denmark, one of three narrow straits connecting the Baltic Sea and the North Sea. The observations (comprised primarily of along-strait, detailed transects of salinity and temperature; continuous observations of flow velocity, salinity, and temperature at a permanent station; and numerous vertical profiles of salinity, temperature, fluorescence, and flow velocity in various locations) show that internal hydraulic control is a frequently occurring phenomenon in the Little Belt. The observations, which are limited to south-going flows of approximately two-layered water masses, show that internal hydraulic control may take either of two configurations, i.e. the lower or the upper layer being the active, accelerating one. This is connected to the depth of the pycnocline on the upstream side and the topography, which is both deepening and contracting toward the narrow part of the Little Belt. The existence of two possible flow configurations is known from theoretical and laboratory studies, but we believe that this has never been observed in nature and reported before. The water masses formed by the intense mixing, which is tightly connected with the presence of control, may be found far downstream of the point of control. The observations show that these particular water masses are associated with chlorophyll concentrations that are considerably higher than in adjacent water masses, showing that control has a considerable influence on the primary production and hence the ecosystem in the area.

Evaluation of clinical curative effects of disposable stitching instrument in redundant prepuce patients

PubMed Central

Wang, Haitao; Chen, Ningjie; Huo, Ran; Yang, Jincun; Li, Xia; Xing, Nan

2017-01-01

The present study aimed to investigate the clinical curative effect of disposable stitching instrument operation in patients with redundant prepuce or phimosis. A total of 102 cases of patients with circumcision were randomly selected (from June 2013 to December 2014) from the department of plastic and aesthetic surgery of our hospital and were randomly divided into control and observation groups (n=51). Patients in the control group were treated by traditional circumcision operation, while patients in the observation group were treated by novel disposable circumcision stitching instrument. Operation time, bleeding volume, incision healing time, postoperative complications and incision aesthetic satisfaction in the groups were observed. As a result, intraoperative bleeding volume of patients in the observation group was significantly less in comparison to the control group. Operation time and incision healing time of patients in the observation group was shorter than that of the control group. Additionally, the incidence of postoperative complications of patients in the observation group was noted to be lower than that of the control group. On the other hand, the incision aesthetic satisfaction of patients in the observation group was higher than that of the control group. Blood vessel counting and nerve fiber counting of tissue specimen in the observation group were more than those of the control group. Postoperative VAS scores of patients in the observation group were significantly lower than that of the control group. Each rating scale scores of EPQ of patients in the observation group improved significantly compared with that of the control group. In conclusion, the present findings show that disposable circumcision stitching instrument operation is more advantageous in comparison to the traditional procedure along with minimal compilations and better post surgery health condition of patients. PMID:28672929

Teacher coaching supported by formative assessment for improving classroom practices.

PubMed

Fabiano, Gregory A; Reddy, Linda A; Dudek, Christopher M

2018-06-01

The present study is a wait-list controlled, randomized study investigating a teacher coaching approach that emphasizes formative assessment and visual performance feedback to enhance elementary school teachers' classroom practices. The coaching model targeted instructional and behavioral management practices as measured by the Classroom Strategies Assessment System (CSAS) Observer and Teacher Forms. The sample included 89 general education teachers, stratified by grade level, and randomly assigned to 1 of 2 conditions: (a) immediate coaching, or (b) waitlist control. Results indicated that, relative to the waitlist control, teachers in immediate coaching demonstrated significantly greater improvements in observations of behavior management strategy use but not for observations of instructional strategy use. Observer- and teacher-completed ratings of behavioral management strategy use at postassessment were significantly improved by both raters; ratings of instructional strategy use were significantly improved for teacher but not observer ratings. A brief coaching intervention improved teachers' use of observed behavior management strategies and self-reported use of behavior management and instructional strategies. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

New insight into the comparative power of quality-control rules that use control observations within a single analytical run.

PubMed

Parvin, C A

1993-03-01

The error detection characteristics of quality-control (QC) rules that use control observations within a single analytical run are investigated. Unlike the evaluation of QC rules that span multiple analytical runs, most of the fundamental results regarding the performance of QC rules applied within a single analytical run can be obtained from statistical theory, without the need for simulation studies. The case of two control observations per run is investigated for ease of graphical display, but the conclusions can be extended to more than two control observations per run. Results are summarized in a graphical format that offers many interesting insights into the relations among the various QC rules. The graphs provide heuristic support to the theoretical conclusions that no QC rule is best under all error conditions, but the multirule that combines the mean rule and a within-run standard deviation rule offers an attractive compromise.

Bleeding risk under selective serotonin reuptake inhibitor (SSRI) antidepressants: A meta-analysis of observational studies.

PubMed

Laporte, Silvy; Chapelle, Céline; Caillet, Pascal; Beyens, Marie-Noëlle; Bellet, Florelle; Delavenne, Xavier; Mismetti, Patrick; Bertoletti, Laurent

2017-04-01

Selective serotonin reuptake inhibitors (SSRIs) have been reported to be potentially associated with an increased risk of bleeding. A meta-analysis of observational studies was conducted to quantify this risk. Case-control and cohort studies investigating bleeding risk under SSRI therapy were retrieved by searching the Medline, Pascal, Google Scholar and Scopus databases. Case-control studies were included if they reported bleeding incidents with and without the use of SSRIs and cohort studies were included if they reported the rate of bleeds among SSRI users and non-users. The main outcome was severe bleeding, whatever the site. Only data concerning SSRI belonging to the ATC class N06AB were used. For both case-control and cohort studies, we recorded the adjusted effect estimates and their 95% confidence intervals (CI). Pooled adjusted odds ratio (OR) estimates were computed for case-control and cohort studies using an inverse-variance model. Meta-analysis of the adjusted ORs of 42 observational studies showed a significant association between SSRI use and the risk of bleeding [OR 1.41 (95% CI 1.27-1.57), random effect model, p<0.0001]. The association was found for the 31 case-control studies (1,255,073 patients), with an increased risk of 41% of bleeding [OR 1.41 (95% CI 1.25-1.60)], as well as for the 11 cohort studies including 187,956 patients [OR 1.36 (95% CI 1.12-1.64)]. Subgroup analyses showed that the association remained constant whatever the characteristics of studies. This meta-analysis shows an increased risk of bleeding of at least 36% (from 12% to 64%) based on the high-level of observational studies with SSRIs use. Copyright © 2016 Elsevier Ltd. All rights reserved.

Profiles of Anger Control in Second-Grade Children: Examination of Self-Report, Observational, and Physiological Components

ERIC Educational Resources Information Center

Smith, Marissa; Hubbard, Julie A.; Laurenceau, Jean-Philippe

2011-01-01

The current study used latent profile analysis (LPA) to examine anger control in 257 second-grade children (approximately 8 years of age). Anger was induced through losing a game and prize to a confederate who cheated. Three components of anger control were assessed: self-report of awareness of anger, observed intensity of angry facial…

A Randomized Controlled Study of Art Observation Training to Improve Medical Student Ophthalmology Skills.

PubMed

Gurwin, Jaclyn; Revere, Karen E; Niepold, Suzannah; Bassett, Barbara; Mitchell, Rebecca; Davidson, Stephanie; DeLisser, Horace; Binenbaum, Gil

2018-01-01

Observation and description are critical to the practice of medicine, and to ophthalmology in particular. However, medical education does not provide explicit training in these areas, and medical students are often criticized for deficiencies in these skills. We sought to evaluate the effects of formal observation training in the visual arts on the general and ophthalmologic observational skills of medical students. Randomized, single-masked, controlled trial. Thirty-six first-year medical students, randomized 1:1 into art-training and control groups. Students in the art-training group were taught by professional art educators at the Philadelphia Museum of Art, during 6 custom-designed, 1.5-hour art observation sessions over a 3-month period. All subjects completed pre- and posttesting, in which they described works of art, retinal pathology images, and external photographs of eye diseases. Grading of written descriptions for observational and descriptive abilities by reviewers using an a priori rubric and masked to group assignment and pretesting/posttesting status. Observational skills, as measured by description testing, improved significantly in the training group (mean change +19.1 points) compared with the control group (mean change -13.5 points), P = 0.001. There were significant improvements in the training vs. control group for each of the test subscores. In a poststudy questionnaire, students reported applying the skills they learned in the museum in clinically meaningful ways at medical school. Art observation training for first-year medical students can improve clinical ophthalmology observational skills. Principles from the field of visual arts, which is reputed to excel in teaching observation and descriptive abilities, can be successfully applied to medical training. Further studies can examine the impact of such training on clinical care. Copyright © 2017 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Boundary control for a flexible manipulator based on infinite dimensional disturbance observer

NASA Astrophysics Data System (ADS)

Jiang, Tingting; Liu, Jinkun; He, Wei

2015-07-01

This paper focuses on disturbance observer and boundary control design for the flexible manipulator in presence of both boundary disturbance and spatially distributed disturbance. Taking the infinite-dimensionality of the flexural dynamics into account, this study proposes a partial differential equation (PDE) model. Since the spatially distributed disturbance is infinite dimensional, it cannot be compensated by the typical disturbance observer, which is designed by finite dimensional approach. To estimate the spatially distributed disturbance, we propose a novel infinite dimensional disturbance observer (IDDO). Applying the IDDO as a feedforward compensator, a boundary control scheme is designed to regulate the joint position and eliminate the elastic vibration simultaneously. Theoretical analysis validates the stability of both the proposed disturbance observer and the boundary controller. The performance of the closed-loop system is demonstrated by numerical simulations.

Randomized controlled trials vs. observational studies: why not just live together?

PubMed

Faraoni, David; Schaefer, Simon Thomas

2016-10-21

Randomized controlled trials (RCTs) are considered the gold standard for clinical research, thus having a high impact on clinical guidelines and our daily patients' care. However, various treatment strategies which we consider "evidence based" have never been subject to a prospective RCT, as we would rate it unethical to withheld an established treatment to individuals in an placebo controlled trial.In a recent BMC Anesthesiology publication, Trentino et al. analyzed the usefulness of observational studies in assessing benefit and risk of different transfusion strategies. The authors nicely reviewed and summarized similarities and differences, advantages and limitations, between different study types frequently used in transfusion medicine. In this interesting article, the authors conclude, that 'when comparing the results of observational studies with RCTs assessing transfusion outcomes, it is important that one consider not only the study method, but also the key elements of the study design'. Thus, in this commentary we now discuss the pro's and con's of different study types, even irrespective of transfusion medicine.

Does Childhood Anxiety Evoke Maternal Control? A Genetically Informed Study

ERIC Educational Resources Information Center

Eley, Thalia C.; Napolitano, Maria; Lau, Jennifer Y. F.; Gregory, Alice M.

2010-01-01

Background: Despite theoretical and empirical support for an association between maternal control and child anxiety, few studies have examined the origins of this association. Furthermore, none use observer-ratings of maternal control within a genetically informative design. This study addressed three questions: 1) do children who experience…

No evidence for common processes of cognitive control and self-control.

PubMed

Scherbaum, Stefan; Frisch, Simon; Holfert, Anna-Maria; O'Hora, Denis; Dshemuchadse, Maja

2018-01-01

Cognitive control and self-control are often used as interchangeable terms. Both terms refer to the ability to pursue long-term goals, but the types of controlled behavior that are typically associated with these terms differ, at least superficially. Cognitive control is observed in the control of attention and the overcoming of habitual responses, while self-control is observed in resistance to short-term impulses and temptations. Evidence from clinical studies and neuroimaging studies suggests that below these superficial differences, common control process (e.g., inhibition) might guide both types of controlled behavior. Here, we study this hypothesis in a behavioral experiment, which interlaced trials of a Simon task with trials of an intertemporal decision task. If cognitive control and self-control depend on a common control process, we expected conflict adaptation from Simon task trials to lead to increased self-control in the intertemporal decision trials. However, despite successful manipulations of conflict and conflict adaptation, we found no evidence for this hypothesis. We investigate a number of alternative explanations of this result and conclude that the differences between cognitive control and self-control are not superficial, but rather reflect differences at the process level. Copyright © 2017 Elsevier B.V. All rights reserved.

Controllability and observability of Boolean networks arising from biology

NASA Astrophysics Data System (ADS)

Li, Rui; Yang, Meng; Chu, Tianguang

2015-02-01

Boolean networks are currently receiving considerable attention as a computational scheme for system level analysis and modeling of biological systems. Studying control-related problems in Boolean networks may reveal new insights into the intrinsic control in complex biological systems and enable us to develop strategies for manipulating biological systems using exogenous inputs. This paper considers controllability and observability of Boolean biological networks. We propose a new approach, which draws from the rich theory of symbolic computation, to solve the problems. Consequently, simple necessary and sufficient conditions for reachability, controllability, and observability are obtained, and algorithmic tests for controllability and observability which are based on the Gröbner basis method are presented. As practical applications, we apply the proposed approach to several different biological systems, namely, the mammalian cell-cycle network, the T-cell activation network, the large granular lymphocyte survival signaling network, and the Drosophila segment polarity network, gaining novel insights into the control and/or monitoring of the specific biological systems.

Assessing validity of observational intervention studies – the Benchmarking Controlled Trials

PubMed Central

Malmivaara, Antti

2016-01-01

Abstract Background: Benchmarking Controlled Trial (BCT) is a concept which covers all observational studies aiming to assess impact of interventions or health care system features to patients and populations. Aims: To create and pilot test a checklist for appraising methodological validity of a BCT. Methods: The checklist was created by extracting the most essential elements from the comprehensive set of criteria in the previous paper on BCTs. Also checklists and scientific papers on observational studies and respective systematic reviews were utilized. Ten BCTs published in the Lancet and in the New England Journal of Medicine were used to assess feasibility of the created checklist. Results: The appraised studies seem to have several methodological limitations, some of which could be avoided in planning, conducting and reporting phases of the studies. Conclusions: The checklist can be used for planning, conducting, reporting, reviewing, and critical reading of observational intervention studies. However, the piloted checklist should be validated in further studies.Key messagesBenchmarking Controlled Trial (BCT) is a concept which covers all observational studies aiming to assess impact of interventions or health care system features to patients and populations.This paper presents a checklist for appraising methodological validity of BCTs and pilot-tests the checklist with ten BCTs published in leading medical journals. The appraised studies seem to have several methodological limitations, some of which could be avoided in planning, conducting and reporting phases of the studies.The checklist can be used for planning, conducting, reporting, reviewing, and critical reading of observational intervention studies. PMID:27238631

Red and processed meat consumption and risk of glioma in adults: A systematic review and meta-analysis of observational studies

PubMed Central

Saneei, Parvane; Willett, Walter; Esmaillzadeh, Ahmad

2015-01-01

Background: These findings from several observational studies, investigated the association between red meat consumption and gliomas, were inconsistent. We conducted a systematic review and meta-analysis of observational studies to summarize available date on the relation between meat intake and risk of glioma. Materials and Methods: A systematic literature search of relevant reports published until May 2014 of the PubMed/Medline, ISI Web of Knowledge, Excerpta Medica database, Ovid database, Google Scholar, and Scopus databases was conducted. From 723 articles yielded in the preliminary literature search, data from eighteen publications (14 case-control, three cohort, and one nested case-control study) on unprocessed red meat, processed meat, and/or total red meat consumption in relation to glioma in adults were included in the analysis. Quality assessment of studies was performed. Random effects model was used to conduct the meta-analysis. Results: We found a positive significant association between unprocessed red meat intake and risk of glioma (relative risk [RR] = 1.30; 95% confidence interval [CI]: 1.08-1.58) after excluding three studies with uncertain type of brain cancer. This analysis included only one cohort study which revealed no relation between unprocessed red meat intake and glioma (RR = 1.75; 95% CI: 0.35-8.77). Consumption of processed meats was not related to increased risk of glioma in population-based case-control studies (RR = 1.26; 95% CI: 1.05-1.51) and reduced risk in hospital-based case-controls (RR = 0.79; 95% CI: 0.65-0.97). No significant association was seen between processed red meat intake and risk of glioma in cohort studies (RR: 1.08; 95% CI: 0.84-1.37). Total red meat consumption was not associated with risk of adult glioma in case-control or cohort studies. Conclusion: In this meta-analysis of 18 observational studies, we found a modest positive association between unprocessed red meat intake and risk of gliomas based almost entirely on case-control studies. Processed red meat was overall not associated with risk of gliomas in case-control or cohort studies. PMID:26600837

Cumulative Evidence of Randomized Controlled and Observational Studies on Catheter-Related Infection Risk of Central Venous Catheter Insertion Site in ICU Patients: A Pairwise and Network Meta-Analysis.

PubMed

Arvaniti, Kostoula; Lathyris, Dimitrios; Blot, Stijn; Apostolidou-Kiouti, Fani; Koulenti, Despoina; Haidich, Anna-Bettina

2017-04-01

Selection of central venous catheter insertion site in ICU patients could help reduce catheter-related infections. Although subclavian was considered the most appropriate site, its preferential use in ICU patients is not generalized and questioned by contradicted meta-analysis results. In addition, conflicting data exist on alternative site selection whenever subclavian is contraindicated. To compare catheter-related bloodstream infection and colonization risk between the three sites (subclavian, internal jugular, and femoral) in adult ICU patients. We searched MEDLINE, EMBASE, Cochrane Central Register of Controlled trials, CINAHL, and ClinicalTrials.gov. Eligible studies were randomized controlled trials and observational ones. Extracted data were analyzed by pairwise and network meta-analysis. Twenty studies were included; 11 were observational, seven were randomized controlled trials for other outcomes, and two were randomized controlled trials for sites. We evaluated 18,554 central venous catheters: 9,331 from observational studies, 5,482 from randomized controlled trials for other outcomes, and 3,741 from randomized controlled trials for sites. Colonization risk was higher for internal jugular (relative risk, 2.25 [95% CI, 1.84-2.75]; I = 0%) and femoral (relative risk, 2.92 [95% CI, 2.11-4.04]; I = 24%), compared with subclavian. Catheter-related bloodstream infection risk was comparable for internal jugular and subclavian, higher for femoral than subclavian (relative risk, 2.44 [95% CI, 1.25-4.75]; I = 61%), and lower for internal jugular than femoral (relative risk, 0.55 [95% CI, 0.34-0.89]; I = 61%). When observational studies that did not control for baseline characteristics were excluded, catheter-related bloodstream infection risk was comparable between the sites. In ICU patients, internal jugular and subclavian may, similarly, decrease catheter-related bloodstream infection risk, when compared with femoral. Subclavian could be suggested as the most appropriate site, whenever colonization risk is considered and not, otherwise, contraindicated. Current evidence on catheter-related bloodstream infection femoral risk, compared with the other sites, is inconclusive.

Cerebrovascular accidents in elderly people treated with antipsychotic drugs: a systematic review.

PubMed

Sacchetti, Emilio; Turrina, Cesare; Valsecchi, Paolo

2010-04-01

After 2002, an association between stroke and antipsychotic use was reported in clinical trials and large database studies. This review considers previous quantitative reviews, newly published clinical trials, and recent observational cohort and case-control studies, and focuses on the clinical significance of the risk for stroke, the difference between typical and atypical antipsychotics, the possible at-risk patient profile and the timing of stroke after exposure. A search of MEDLINE covering the period from 1966 to June 2009 was carried out using selected keywords. Inclusion criteria were (i) quantitative reviews on stroke and antipsychotics; (ii) double-blind, placebo-controlled clinical trials involving patients with dementia treated with antipsychotics; and (iii) observational database cohort studies and observational case-control studies investigating the association between stroke and antipsychotics. Clinical trials were excluded if they were single-blind or if patients were affected by dementia and/or other neurological illnesses. Four reviews with aggregate data, 2 meta-analyses, 13 randomized, double-blind, controlled trials, 7 observational cohort studies and 4 observational case-control studies were selected and analysed. The incidence of cerebrovascular accidents (CVAs) was found to be very low in aggregate reviews and meta-analyses (2-4%). When the number collected was sufficiently high, or different drug treatments were grouped together, the higher rate in subjects exposed to antipsychotics was statistically significant. Inspection of other randomized controlled clinical trials, not included in aggregate reviews and meta-analyses, reported similar rates of CVAs. The majority of observational cohort studies compared typical and atypical antipsychotics and no significant class differences were found. A comparison with non-users was carried out in some cohort studies. In case-control studies, the probability of CVAs in users compared with non-users was in the range of 1.3- to 2-fold greater. Preliminary data also indicate that the highest risk of stroke is related to the first weeks of treatment, and a risk profile for stroke is emerging, such as older age, cognitive impairment and vascular illness. Different pathophysiological pathways may be involved, ranging from the facilitation of thrombosis, pre-existing cardiovascular factors, sedation and a common diathesis for stroke of dementia, schizophrenia and affective illness. Before prescribing an antipsychotic, clinicians should weigh all the risk factors for a given patient and consider not only the indications as provided by the regulatory agencies, but also the overall effectiveness of typical and atypical antipsychotics.

Birth Weight and Acute Childhood Leukemia: A Meta-analysis of Observational Studies

DTIC Science & Technology

2005-03-22

22 MAR 2005 2. REPORT TYPE 3. DATES COVERED - 4. TITLE AND SUBTITLE Birth Weight and Acute Childhood Leukemia: A Meta - analysis of Observational...and to quantify the strength of the relationships. We conducted a meta - analysis of nine case-control studies (published between 1991 and 2004...Based on a meta - analysis of only three case-control studies (published between 1997 and 2004) involving over 700 children with AML and over 1,900

Model Predictive Flight Control System with Full State Observer using H∞ Method

NASA Astrophysics Data System (ADS)

Sanwale, Jitu; Singh, Dhan Jeet

2018-03-01

This paper presents the application of the model predictive approach to design a flight control system (FCS) for longitudinal dynamics of a fixed wing aircraft. Longitudinal dynamics is derived for a conventional aircraft. Open loop aircraft response analysis is carried out. Simulation studies are illustrated to prove the efficacy of the proposed model predictive controller using H ∞ state observer. The estimation criterion used in the {H}_{∞} observer design is to minimize the worst possible effects of the modelling errors and additive noise on the parameter estimation.

[Clinical observation on the influence of earthquake crush injury on postoperative wound healing of extremity fractures].

PubMed

Chen, Fu-hong; Chen, Ze; Duan, Heng-qiong; Wan, Zhong-xian

2008-10-01

To observe the influence of earthquake crush injury on postoperative wound healing of extremity fractures. The study involved 85 patients with extremities fracture underwent internal fixation operation in 3 group, including 28 earthquake casualties with crush injuries in observation group, 27 earthquake casualties without crush injuries in control I group and 30 local patients during the same period in control II group. Urine routine, blood creatine kinase (CK) and wound conditions of patients in 3 groups were observed respectively. There was no significant difference in Urine routine and blood CK between 3 groups and was significant difference in wound conditions between observation group and each control group. Earthquake crush injuries can influence the postoperative wound healing of extremity fractures.

Alcohol Intake and Risk of Thyroid Cancer: A Meta-Analysis of Observational Studies.

PubMed

Hong, Seung-Hee; Myung, Seung-Kwon; Kim, Hyeon Suk

2017-04-01

The purpose of this study was to assess whether alcohol intake is associated with the risk of thyroid cancer by a meta-analysis of observational studies. We searched PubMed and EMBASE in June of 2015 to locate eligible studies. We included observational studies such as cross-sectional studies, case-control studies, and cohort studies reporting odd ratios (ORs) or relative risk (RRs) with 95% confidence intervals (CIs). We included 33 observational studies with two cross-sectional studies, 20 case-controls studies, and 11 cohort studies, which involved a total of 7,725 thyroid cancer patients and 3,113,679 participants without thyroid cancer in the final analysis. In the fixed-effect model meta-analysis of all 33 studies, we found that alcohol intake was consistently associated with a decreased risk of thyroid cancer (OR or RR, 0.74; 95% CI, 0.67 to 0.83; I 2 =38.6%). In the subgroup meta-analysis by type of study, alcohol intake also decreased the risk of thyroid cancer in both case-control studies (OR, 0.77; 95% CI, 0.65 to 0.92; I 2 =29.5%; n=20) and cohort studies (RR, 0.70; 95% CI, 0.60 to 0.82; I 2 =0%; n=11). Moreover, subgroup meta-analyses by type of thyroid cancer, gender, amount of alcohol consumed, and methodological quality of study showed that alcohol intake was significantly associated with a decreased risk of thyroid cancer. The current meta-analysis of observational studies found that, unlike most of other types of cancer, alcohol intake decreased the risk of thyroid cancer.

Bias reduction in repeated-measures observational studies by the use of propensity score: the case of enteral sedation for critically ill patients.

PubMed

Umbrello, Michele; Mistraletti, Giovanni; Corbella, Davide; Cigada, Marco; Salini, Silvia; Morabito, Alberto; Iapichino, Gaetano

2012-12-01

Within the evidence-based medicine paradigm, randomized controlled trials represent the "gold standard" to produce reliable evidence. Indeed, planning and implementing randomized controlled trials in critical care medicine presents limitations because of intrinsic and structural problems. As a consequence, observational studies still occur frequently. In these cases, propensity score (PS) (probability of receiving a treatment conditional on observed covariates) is an increasingly used technique to adjust the results. Few studies addressed the specific issue of a PS correction of repeated-measures designs. Three techniques for correcting the analysis of nonrandomized designs (matching, stratification, regression adjustment) are presented in a tutorial form and applied to a real case study: the comparison between intravenous and enteral sedative therapy in the intensive care unit setting. After showing the results before and after the use of PS, we suggest that such a tool allows to partially overcoming the bias associated with the observational nature of the study. It permits to correct the estimates for any observed covariate, while unobserved confounders cannot be controlled for. Propensity score represents a useful additional tool to estimate the effects of treatments in nonrandomized studies. In the case study, an enteral sedation approach was equally effective to an intravenous regime, allowing for a lower level of sedation and spare of resources. Copyright © 2012 Elsevier Inc. All rights reserved.

Attitude output feedback control for rigid spacecraft with finite-time convergence.

PubMed

Hu, Qinglei; Niu, Guanglin

2017-09-01

The main problem addressed is the quaternion-based attitude stabilization control of rigid spacecraft without angular velocity measurements in the presence of external disturbances and reaction wheel friction as well. As a stepping stone, an angular velocity observer is proposed for the attitude control of a rigid body in the absence of angular velocity measurements. The observer design ensures finite-time convergence of angular velocity state estimation errors irrespective of the control torque or the initial attitude state of the spacecraft. Then, a novel finite-time control law is employed as the controller in which the estimate of the angular velocity is used directly. It is then shown that the observer and the controlled system form a cascaded structure, which allows the application of the finite-time stability theory of cascaded systems to prove the finite-time stability of the closed-loop system. A rigorous analysis of the proposed formulation is provided and numerical simulation studies are presented to help illustrate the effectiveness of the angular-velocity observer for rigid spacecraft attitude control. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

Observations on side-swimming rainbow trout Oncorhynchus mykiss in water recirculation aquaculture systems

USDA-ARS?s Scientific Manuscript database

During a controlled 6-month study using six replicated water recirculation aquaculture systems (WRAS), it was observed that rainbow trout Oncorhynchus mykiss in all WRAS exhibited a higher-than-normal prevalence of side-swimming (i.e. controlled, forward swimming, but with misaligned orientation suc...

Observations on root disease of container whitebark pine seedlings treated with biological controls

Treesearch

R. Kasten Dumroese

2008-01-01

I observed that whitebark pine (Pinus albicaulis Engelm. [Pinaceae]) germinants treated with biological controls, one commercially available (Trichoderma harzianum strain T-22), and the other being studied for potential efficacy (Fusarium oxysporum isolate Q12), experienced less seedling mortality caused by root disease than did a...

Study designs may influence results: the problems with questionnaire-based case-control studies on the epidemiology of glioma.

PubMed

Johansen, Christoffer; Schüz, Joachim; Andreasen, Anne-Marie Serena; Dalton, Susanne Oksbjerg

2017-03-28

Glioma is a rare brain tumour with a very poor prognosis and the search for modifiable factors is intense. We reviewed the literature concerning risk factors for glioma obtained in case-control designed epidemiological studies in order to discuss the influence of this methodology on the observed results. When reviewing the association between three exposures, medical radiation, exogenous hormone use and allergy, we critically appraised the evidence from both case-control and cohort studies. For medical radiation and hormone replacement therapy (HRT), questionnaire-based case-control studies appeared to show an inverse association, whereas nested case-control and cohort studies showed no association. For allergies, the inverse association was observed irrespective of study design. We recommend that the questionnaire-based case-control design be placed lower in the hierarchy of studies for establishing cause-and-effect for diseases such as glioma. We suggest that a state-of-the-art case-control study should, as a minimum, be accompanied by extensive validation of the exposure assessment methods and the representativeness of the study sample with regard to the exposures of interest. Otherwise, such studies cannot be regarded as 'hypothesis testing' but only 'hypothesis generating'. We consider that this holds true for all questionnaire-based case-control studies on cancer and other chronic diseases, although perhaps not to the same extent for each exposure-outcome combination.

Software and electronic developments for TUG - T60 robotic telescope

NASA Astrophysics Data System (ADS)

Parmaksizoglu, M.; Dindar, M.; Kirbiyik, H.; Helhel, S.

2014-12-01

A robotic telescope is a telescope that can make observations without hands-on human control. Its low level behavior is automatic and computer-controlled. Robotic telescopes usually run under the control of a scheduler, which provides high-level control by selecting astronomical targets for observation. TUBITAK National Observatory (TUG) T60 Robotic Telescope is controlled by open source OCAAS software, formally named TALON. This study introduces the improvements on TALON software, new electronic and mechanic designs. The designs and software improvements were implemented in the T60 telescope control software and tested on the real system successfully.

Participation in population-based case-control studies: does the observed decline vary by socio-economic status?

PubMed

Mazloum, Marie; Bailey, Helen D; Heiden, Tamika; Armstrong, Bruce K; de Klerk, Nicholas; Milne, Elizabeth

2012-05-01

An Australian study of childhood leukaemia (Aus-ALL) previously reported that control participation was positively associated with socio-economic status (SES). A similar study of childhood brain tumours (Aus-CBT) was carried out 4 years later, and this paper compares control participation and its relationship with SES in the two studies. To assess the representativeness of controls in terms of SES, the addresses of controls were linked to Australian Bureau of Statistics Census 2006 Collection Districts (CDs), and hence to area-based indices of SES. Independent sample t-tests and chi-squared tests were used to compare the SES indices of CDs where Aus-CBT controls lived with those where Aus-ALL controls lived and with those of all CDs where Australian families lived. The overall percentage of eligible families who agreed to participate was lower in Aus-CBT (53.9%) than in Aus-ALL (70.3%). Control families in both studies were of higher SES than the general population, while the distribution of SES among recruited controls was similar in both studies. These findings provide some reassurance that the observed decline in research participation over time may not be associated with an increasingly unrepresentative participant population. © 2012 Blackwell Publishing Ltd.

Concordance of Results from Randomized and Observational Analyses within the Same Study: A Re-Analysis of the Women's Health Initiative Limited-Access Dataset.

PubMed

Bolland, Mark J; Grey, Andrew; Gamble, Greg D; Reid, Ian R

2015-01-01

Observational studies (OS) and randomized controlled trials (RCTs) often report discordant results. In the Women's Health Initiative Calcium and Vitamin D (WHI CaD) RCT, women were randomly assigned to CaD or placebo, but were permitted to use personal calcium and vitamin D supplements, creating a unique opportunity to compare results from randomized and observational analyses within the same study. WHI CaD was a 7-year RCT of 1g calcium/400IU vitamin D daily in 36,282 post-menopausal women. We assessed the effects of CaD on cardiovascular events, death, cancer and fracture in a randomized design- comparing CaD with placebo in 43% of women not using personal calcium or vitamin D supplements- and in a observational design- comparing women in the placebo group (44%) using personal calcium and vitamin D supplements with non-users. Incidence was assessed using Cox proportional hazards models, and results from the two study designs deemed concordant if the absolute difference in hazard ratios was ≤0.15. We also compared results from WHI CaD to those from the WHI Observational Study(WHI OS), which used similar methodology for analyses and recruited from the same population. In WHI CaD, for myocardial infarction and stroke, results of unadjusted and 6/8 covariate-controlled observational analyses (age-adjusted, multivariate-adjusted, propensity-adjusted, propensity-matched) were not concordant with the randomized design results. For death, hip and total fracture, colorectal and total cancer, unadjusted and covariate-controlled observational results were concordant with randomized results. For breast cancer, unadjusted and age-adjusted observational results were concordant with randomized results, but only 1/3 other covariate-controlled observational results were concordant with randomized results. Multivariate-adjusted results from WHI OS were concordant with randomized WHI CaD results for only 4/8 endpoints. Results of randomized analyses in WHI CaD were concordant with observational analyses for 5/8 endpoints in WHI CaD and 4/8 endpoints in WHI OS.

Concordance of Results from Randomized and Observational Analyses within the Same Study: A Re-Analysis of the Women’s Health Initiative Limited-Access Dataset

PubMed Central

Bolland, Mark J.; Grey, Andrew; Gamble, Greg D.; Reid, Ian R.

2015-01-01

Background Observational studies (OS) and randomized controlled trials (RCTs) often report discordant results. In the Women’s Health Initiative Calcium and Vitamin D (WHI CaD) RCT, women were randomly assigned to CaD or placebo, but were permitted to use personal calcium and vitamin D supplements, creating a unique opportunity to compare results from randomized and observational analyses within the same study. Methods WHI CaD was a 7-year RCT of 1g calcium/400IU vitamin D daily in 36,282 post-menopausal women. We assessed the effects of CaD on cardiovascular events, death, cancer and fracture in a randomized design- comparing CaD with placebo in 43% of women not using personal calcium or vitamin D supplements- and in a observational design- comparing women in the placebo group (44%) using personal calcium and vitamin D supplements with non-users. Incidence was assessed using Cox proportional hazards models, and results from the two study designs deemed concordant if the absolute difference in hazard ratios was ≤0.15. We also compared results from WHI CaD to those from the WHI Observational Study(WHI OS), which used similar methodology for analyses and recruited from the same population. Results In WHI CaD, for myocardial infarction and stroke, results of unadjusted and 6/8 covariate-controlled observational analyses (age-adjusted, multivariate-adjusted, propensity-adjusted, propensity-matched) were not concordant with the randomized design results. For death, hip and total fracture, colorectal and total cancer, unadjusted and covariate-controlled observational results were concordant with randomized results. For breast cancer, unadjusted and age-adjusted observational results were concordant with randomized results, but only 1/3 other covariate-controlled observational results were concordant with randomized results. Multivariate-adjusted results from WHI OS were concordant with randomized WHI CaD results for only 4/8 endpoints. Conclusions Results of randomized analyses in WHI CaD were concordant with observational analyses for 5/8 endpoints in WHI CaD and 4/8 endpoints in WHI OS. PMID:26440516

Executive Control Goes to School: Implications of Preschool Executive Performance for Observed Elementary Classroom Learning Engagement

PubMed Central

Nelson, Timothy D.; Nelson, Jennifer Mize; James, Tiffany D.; Clark, Caron A.C.; Kidwell, Katherine M.; Espy, Kimberly Andrews

2017-01-01

The transition to elementary school is accompanied by increasing demands for children to regulate their attention and behavior within the classroom setting. Executive control (EC) may be critical for meeting these demands; however, few studies have rigorously examined the association between EC and observed classroom behavior. This study examined EC in preschool (age 5 years, 3 months) as a predictor of classroom learning engagement behaviors in first grade, using a battery of performance-based EC tasks and live classroom observations in a longitudinal sample of 313 children. Multilevel modeling results indicated that stronger EC predicted more focused engagement and fewer task management and competing responses, controlling for socioeconomic status, child sex, and age at observations. Results suggest that early EC may support subsequent classroom engagement behaviors that are critical for successful transition to elementary school and long-term learning trajectories. PMID:28358540

A prospective study of musculoskeletal outcomes among manufacturing workers: II. Effects of psychosocial stress and work organization factors.

PubMed

Gerr, Fredric; Fethke, Nathan B; Anton, Dan; Merlino, Linda; Rosecrance, John; Marcus, Michele; Jones, Michael P

2014-02-01

The aim of this study was to characterize associations between psychosocial and work organizational risk factors and upper-extremity musculoskeletal symptoms and disorders. Methodological limitations of previous studies of psychosocial and work organizational risk factors and musculoskeletal outcomes have produced inconsistent associations. In this prospective epidemiologic study of 386 workers, questionnaires to assess decision latitude ("control") and psychological job demands ("demand") were administered to study participants and were used to classify them into job strain "quadrants". Measures of job stress and job change were collected during each week of follow-up. Incident hand/arm and neck/shoulder symptoms and disorders were ascertained weekly. Associations between exposure measures and musculoskeletal outcomes were estimated with proportional hazard methods. When compared to the low-demand/high-control job strain referent category, large increases in risk of hand/arm disorders were observed for both high-demand/high-control (hazard ratio [HR] = 4.49, 95% confidence interval [CI] = [1.23, 16.4]) and high-demand/low-control job strain categories (HR = 5.18,95% CI = [1.39, 19.4]). Similar associations were observed for hand/arm symptoms. A strong association was also observed between the low-demand/low-control job strain category and neck/shoulder disorders (HR = 6.46, 95% CI = [1.46, 28.6]). Statistically significant associations were also observed between weekly stress level and weekly job change and several musculoskeletal outcomes. Associations between psychosocial risk factors and work organizational factors and musculoskeletal outcomes were large and in the hypothesized direction. Prevention of occupational musculoskeletal disorders may require attention to psychosocial and work organizational factors in addition to physical factors. Methods to control adverse effects of psychosocial and work organizational risk factors should be explored.

Acrylamide and glycidamide hemoglobin adducts and epithelial ovarian cancer: a nested case-control study in non-smoking postmenopausal women from the EPIC cohort

PubMed Central

Obón-Santacana, Mireia; Lujan-Barroso, Leila; Travis, Ruth C.; Freisling, Heinz; Ferrari, Pietro; Severi, Gianluca; Baglietto, Laura; Boutron-Ruault, Marie-Christine; Fortner, Renée T.; Ose, Jennifer; Boeing, Heiner; Menéndez, Virginia; Sánchez-Cantalejo, Emilio; Chamosa, Saioa; Huerta Castaño, José María; Ardanaz, Eva; Khaw, Kay-Tee; Wareham, Nick; Merritt, Melissa A.; Gunter, Marc J.; Trichopoulou, Antonia; Papatesta, Eleni-Maria; Klinaki, Eleni; Saieva, Calogero; Tagliabue, Giovanna; Tumino, Rosario; Sacerdote, Carlotta; Mattiello, Amalia; Bueno-de-Mesquita, H.B.; Peeters, Petra H.; Onland-Moret, N. Charlotte; Idahl, Annika; Lundin, Eva; Weiderpass, Elisabete; Vesper, Hubert W.; Riboli, Elio; Duell, Eric J

2015-01-01

Background Acrylamide was classified as ‘probably carcinogenic to humans (group 2A)’ by the International Agency for Research on Cancer. Epithelial ovarian cancer (EOC) is the fourth cause of cancer mortality in women. Five epidemiological studies have evaluated the association between EOC risk and dietary acrylamide intake assessed using food frequency questionnaires, and one nested case-control study evaluated hemoglobin adducts of acrylamide (HbAA) and its metabolite glycidamide (HbGA) and EOC risk; the results of these studies were inconsistent. Methods A nested case-control study in non-smoking postmenopausal women (334 cases, 417 controls) was conducted within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Unconditional logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals (CI) for the association between HbAA, HbGA, HbAA+HbGA, and HbGA/HbAA and EOC and invasive serous EOC risk. Results No overall associations were observed between biomarkers of acrylamide exposure analyzed in quintiles and EOC risk; however, positive associations were observed between some middle quintiles of HbGA and HbAA+HbGA. Elevated but non-statistically significant ORs for serous EOC were observed for HbGA and HbAA+HbGA (ORQ5vsQ1:1.91, 95%CI:0.96-3.81 and ORQ5vsQ1:1.90, 95%CI:0.94-3.83, respectively); however, no linear dose-response trends were observed. Conclusion This EPIC nested case-control study failed to observe a clear association between biomarkers of acrylamide exposure and the risk of EOC or invasive serous EOC. Impact It is unlikely that dietary acrylamide exposure increases ovarian cancer risk; however, additional studies with larger sample size should be performed to exclude any possible association with EOC risk. PMID:26376083

Knowledge, Attitude, Practice, and Status of Infection Control among Iranian Dentists and Dental Students: A Systematic Review

PubMed Central

Moradi Khanghahi, Behnam; Jamali, Zahra; Pournaghi Azar, Fatemeh; Naghavi Behzad, Mohammad; Azami-Aghdash, Saber

2013-01-01

Background and aims Infection control is an important issue in dentistry, and the dentists are primarily responsible for observing the relevant procedures. Therefore, the present study evaluated knowledge, attitude, practice, and status of infection control among Iranian dentists through systematic review of published results. Materials and methods In this systematic review, the required data was collected searching for keywords including infection, infection control, behavior, performance, practice, attitude, knowledge, dent*, prevention, Iran* and their Persian equivalents in PubMed, Science Direct, Iranmedex, SID, Medlib, and Magiran databases with a time limit of 1985 to 2012. Out of 698 articles, 15 completely related articles were finally considered and the rest were excluded due to lake of relev-ance to the study goals. The required data were extracted and summarized in an Extraction Table and were analyzed ma-nually. Results Evaluating the results of studies indicated inappropriate knowledge, attitude, and practice regarding infection control among Iranian dentists and dental students. Using personal protection devices and observing measures required for infection control were not in accordance with global standards. Conclusion The knowledge, attitudes, and practice of infection control in Iranian dental settings were found to be inadequate. Therefore, dentists should be educated more on the subject and special programs should be in place to monitor the dental settings for observing infection control standards. PMID:23875081

Sleep disturbances in long-term immigrants with chronic mountain sickness: a comparison with healthy immigrants at high altitude.

PubMed

Guan, Wei; Ga, Qin; Li, Rong; Bai, Zhen-Zhong; Wuren, Tana; Wang, Jin; Yang, Ying-Zhong; Li, Yu-Hong; Ge, Ri-Li

2015-01-15

The aim of this study was to examine sleep disturbances in patients with chronic mountain sickness (CMS). The sleep of 14 patients with CMS and 11 healthy controls with or without sleep disorders (control N: without sleep disorders; control D: with sleep disorders) was studied by polysomnography. Hypopnea was the sleep disorder most commonly suffered by CMS patients and control D subjects. No major differences were observed in sleep structure between CMS and control groups, with the exception of shorter rapid eye movement latency in controls and increased deep non-rapid eye movement in the control N group. Periodic breathing was observed in only two study participants, one each in the CMS and control D groups. The level of saturated oxygen was significantly lower in the CMS group during sleep than the control groups (P<0.05). CMS scores were positively correlated with the apnea-hypopnea index, and negatively correlated with saturated oxygen levels. These results demonstrate that sleep disorders and nocturnal hypoxia are important in the development of CMS. Copyright © 2014 Elsevier B.V. All rights reserved.

Evaluation of two momentum control variable schemes and their impact on the variational assimilation of radarwind data: Case study of a squall line

NASA Astrophysics Data System (ADS)

Li, Xin; Zeng, Mingjian; Wang, Yuan; Wang, Wenlan; Wu, Haiying; Mei, Haixia

2016-10-01

Different choices of control variables in variational assimilation can bring about different influences on the analyzed atmospheric state. Based on the WRF model's three-dimensional variational assimilation system, this study compares the behavior of two momentum control variable options—streamfunction velocity potential ( ψ-χ) and horizontal wind components ( U-V)—in radar wind data assimilation for a squall line case that occurred in Jiangsu Province on 24 August 2014. The wind increment from the single observation test shows that the ψ-χ control variable scheme produces negative increments in the neighborhood around the observation point because streamfunction and velocity potential preserve integrals of velocity. On the contrary, the U-V control variable scheme objectively reflects the information of the observation itself. Furthermore, radial velocity data from 17 Doppler radars in eastern China are assimilated. As compared to the impact of conventional observation, the assimilation of radar radial velocity based on the U-V control variable scheme significantly improves the mesoscale dynamic field in the initial condition. The enhanced low-level jet stream, water vapor convergence and low-level wind shear result in better squall line forecasting. However, the ψ-χ control variable scheme generates a discontinuous wind field and unrealistic convergence/divergence in the analyzed field, which lead to a degraded precipitation forecast.

Use of benzodiazepine and risk of cancer: A meta-analysis of observational studies.

PubMed

Kim, Hong-Bae; Myung, Seung-Kwon; Park, Yon Chul; Park, Byoungjin

2017-02-01

Several observational epidemiological studies have reported inconsistent results on the association between the use of benzodiazepine and the risk of cancer. We investigated the association by using a meta-analysis. We searched PubMed, EMBASE, and the bibliographies of relevant articles to locate additional publications in January 2016. Three evaluators independently reviewed and selected eligible studies based on predetermined selection criteria. Of 796 articles meeting our initial criteria, a total of 22 observational epidemiological studies with 18 case-control studies and 4 cohort studies were included in the final analysis. Benzodiazepine use was significantly associated with an increased risk of cancer (odds ratio [OR] or relative risk [RR] 1.19; 95% confidence interval 1.16-1.21) in a random-effects meta-analysis of all studies. Subgroup meta-analyses by various factors such as study design, type of case-control study, study region, and methodological quality of study showed consistent findings. Also, a significant dose-response relationship was observed between the use of benzodiazepine and the risk of cancer (p for trend <0.01). The current meta-analysis of observational epidemiological studies suggests that benzodiazepine use is associated with an increased risk of cancer. © 2016 UICC.

Evaluation of interobserver agreement for postoperative pain and sedation assessment in cats.

PubMed

Benito, Javier; Monteiro, Beatriz P; Beauchamp, Guy; Lascelles, B Duncan X; Steagall, Paulo V

2017-09-01

OBJECTIVE To evaluate agreement between observers with different training and experience for assessment of postoperative pain and sedation in cats by use of a dynamic and interactive visual analog scale (DIVAS) and for assessment of postoperative pain in the same cats with a multidimensional composite pain scale (MCPS). DESIGN Randomized, controlled, blinded study. ANIMALS 45 adult cats undergoing ovariohysterectomy. PROCEDURES Cats received 1 of 3 preoperative treatments: bupivacaine, IP; meloxicam, SC with saline (0.9% NaCl) solution, IP, (positive control); or saline solution only, IP (negative control). All cats received premedication with buprenorphine prior to general anesthesia. An experienced observer (observer 1; male; native language, Spanish) used scales in English, and an inexperienced observer (observer 2; female; native language, French) used scales in French to assess signs of sedation and pain. Rescue analgesia was administered according to MCPS scoring by observer 1. Mean pain and sedation scores per treatment and time point, proportions of cats in each group with MCPS scores necessitating rescue analgesia, and mean MCPS scores assigned at the time of rescue analgesia were compared between observers. Agreement was assessed by intraclass correlation coefficient determination. Percentage disagreement between observers on the need for rescue analgesia was calculated. RESULTS Interobserver agreements for pain scores were good, and that for sedation scores was fair. On the basis of observer 1's MCPS scores, a greater proportion of cats in the negative control group received rescue analgesia than in the bupivacaine or positive control groups. Scores from observer 2 indicated a greater proportion of cats in the negative control group than in the positive control group required rescue analgesia but identified no significant difference between the negative control and bupivacaine groups for this variable. Overall, disagreement regarding need for rescue analgesia was identified for 22 of 360 (6.1%) paired observations. CONCLUSIONS AND CLINICAL RELEVANCE Interobserver differences in assessing pain can lead to different conclusions regarding treatment effectiveness.

Association study of dopamine D3 receptor gene and schizophrenia

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

Kennedy, J.L.; Billett, E.A.; Macciardi, F.M.

Several groups have reported an association between schizophrenia and the MscI polymorphism in the first exon of the dopamine D3 receptor gene (DRD3). We studied this polymorphism using a North American sample (117 patients plus 188 controls) and an Italian sample (97 patients plus 64 controls). In the first part of the study, we compared allele frequencies of schizophrenia patients and unmatched controls and observed a significant difference in the total sample (P = 0.01). The second part of the study involved a case control approach in which each schizophrenia patient was matched to a control of the same sex,more » and of similar age and ethnic background. The DRD3 allele frequencies of patients and controls revealed no significant difference between the two groups in the Italian (N = 53) or the North American (N = 54) matched populations; however, when these two matched samples were combined, a significant difference was observed (P = 0.026). Our results suggest that the MscI polymorphism may be associated with schizophrenia in the populations studied. 32 refs., 2 tabs.« less

How College Students Search the Internet for Weight Control and Weight Management Information: An Observational Study

ERIC Educational Resources Information Center

Senkowski, Valerie; Branscum, Paul

2015-01-01

Background: Few studies have attempted to examine how young adults search for health information on the Internet, especially information related to weight control and weight management. Purpose: The purpose of this study was to determine search strategies that college students used for finding information related to weight control and weight…

Evaluating the Impact of Database Heterogeneity on Observational Study Results

PubMed Central

Madigan, David; Ryan, Patrick B.; Schuemie, Martijn; Stang, Paul E.; Overhage, J. Marc; Hartzema, Abraham G.; Suchard, Marc A.; DuMouchel, William; Berlin, Jesse A.

2013-01-01

Clinical studies that use observational databases to evaluate the effects of medical products have become commonplace. Such studies begin by selecting a particular database, a decision that published papers invariably report but do not discuss. Studies of the same issue in different databases, however, can and do generate different results, sometimes with strikingly different clinical implications. In this paper, we systematically study heterogeneity among databases, holding other study methods constant, by exploring relative risk estimates for 53 drug-outcome pairs and 2 widely used study designs (cohort studies and self-controlled case series) across 10 observational databases. When holding the study design constant, our analysis shows that estimated relative risks range from a statistically significant decreased risk to a statistically significant increased risk in 11 of 53 (21%) of drug-outcome pairs that use a cohort design and 19 of 53 (36%) of drug-outcome pairs that use a self-controlled case series design. This exceeds the proportion of pairs that were consistent across databases in both direction and statistical significance, which was 9 of 53 (17%) for cohort studies and 5 of 53 (9%) for self-controlled case series. Our findings show that clinical studies that use observational databases can be sensitive to the choice of database. More attention is needed to consider how the choice of data source may be affecting results. PMID:23648805

Control strategies and noncompliance in abusive mother-child dyads: an observational study.

PubMed

Oldershaw, L; Walters, G C; Hall, D K

1986-06-01

The present observational study of child abuse has isolated parental control strategies and child response as a promising area of investigation. The social interaction of 10 abusive and 10 matched control mothers and their preschool children was videotaped in a simulated home environment involving both structured and unstructured activities. A coding scheme was developed to record interactional behavior in each dyad. Particular emphasis was placed on the analysis of mother command/child compliance sequences. Compared to controls, abusive mothers employed more commands, and more power-assertive and less positively oriented control strategies. They were also more intrusive, more inconsistent in their use of parenting techniques, displayed more flattened affect throughout their control interactions, and were less flexible in their attempts to gain compliance from the child. In turn, children of abusive mothers demonstrated far more noncompliant behavior than their control counterparts.

Benchmarking Controlled Trial--a novel concept covering all observational effectiveness studies.

PubMed

Malmivaara, Antti

2015-06-01

The Benchmarking Controlled Trial (BCT) is a novel concept which covers all observational studies aiming to assess effectiveness. BCTs provide evidence of the comparative effectiveness between health service providers, and of effectiveness due to particular features of the health and social care systems. BCTs complement randomized controlled trials (RCTs) as the sources of evidence on effectiveness. This paper presents a definition of the BCT; compares the position of BCTs in assessing effectiveness with that of RCTs; presents a checklist for assessing methodological validity of a BCT; and pilot-tests the checklist with BCTs published recently in the leading medical journals.

Comparison of Estimates between Cohort and Case-Control Studies in Meta-Analyses of Therapeutic Interventions: A Meta-Epidemiological Study.

PubMed

Lanza, Amy; Ravaud, Philippe; Riveros, Carolina; Dechartres, Agnes

2016-01-01

Observational studies are increasingly being used for assessing therapeutic interventions. Case-control studies are generally considered to have greater risk of bias than cohort studies, but we lack evidence of differences in effect estimates between the 2 study types. We aimed to compare estimates between cohort and case-control studies in meta-analyses of observational studies of therapeutic interventions by using a meta-epidemiological study. We used a random sample of meta-analyses of therapeutic interventions published in 2013 that included both cohort and case-control studies assessing a binary outcome. For each meta-analysis, the ratio of estimates (RE) was calculated by comparing the estimate in case-control studies to that in cohort studies. Then, we used random-effects meta-analysis to estimate a combined RE across meta-analyses. An RE < 1 indicated that case-control studies yielded larger estimates than cohort studies. The final analysis included 23 meta-analyses: 138 cohort and 133 case-control studies. Treatment effect estimates did not significantly differ between case-control and cohort studies (combined RE 0.97 [95% CI 0.86-1.09]). Heterogeneity was low, with between-meta-analysis variance τ2 = 0.0049. Estimates did not differ between case-control and prospective or retrospective cohort studies (RE = 1.05 [95% CI 0.96-1.15] and RE = 0.99 [95% CI, 0.83-1.19], respectively). Sensitivity analysis of studies reporting adjusted estimates also revealed no significant difference (RE = 1.03 [95% CI 0.91-1.16]). Heterogeneity was also low for these analyses. We found no significant difference in treatment effect estimates between case-control and cohort studies assessing therapeutic interventions.

Observational studies: a valuable source for data on the true value of RA therapies.

PubMed

van Vollenhoven, Ronald F; Severens, Johan L

2011-03-01

The validity of observational studies is sometimes questioned because of the limitations of non-randomly assigned controls, various biases such as channeling bias, confounding by indication, and other pitfalls. Yet, (post-marketing) observational data can provide important information regarding not only drug safety but also the effectiveness and appropriate use of agents in the real world, outside of clinical trials. Observational studies also provide data regarding the wider value of these agents in terms of, for example, reducing the need for surgical procedures, reducing absenteeism and increasing productivity. Importantly, data from some observational registry studies have subsequently been confirmed by clinical trials, supporting the overall validity of the registry-based approach. Observational studies also allow measures such as health assessment questionnaire scores, disease activity scores, and glucocorticoid use over time to be monitored for longer periods. Furthermore, observational data in real, less strictly selected patients without the constraints of formal study populations may produce findings not observed in clinical trials but that warrant further investigation in a controlled trial environment. For example, recent data from the Stockholm tumor necrosis factor follow-up registry in Sweden showed increases in the time people worked after initiation of biologics that, surprisingly, continued into the fourth and fifth years of treatment--a finding not observed with standardized outcomes. Observational studies are truly an underappreciated and valuable source of data on the real value of anti-rheumatic therapies, and these data are essential for making sound decisions regarding coverage and reimbursement.

The Role of Selective Attention in Matching Observed and Executed Actions

ERIC Educational Resources Information Center

Chong, Trevor T.-J.; Cunnington, Ross; Williams, Mark A.; Mattingley, Jason B.

2009-01-01

Substantial evidence suggests that observed actions can engage their corresponding motor representations within the observer. It is currently believed that this process of observation-execution matching occurs relatively automatically, without the need for top-down control. In this study we tested the susceptibility of the observation-execution…

Conjugated Equine Estrogens and Breast Cancer Risk in the Women’s Health Initiative Clinical Trial and Observational Study

PubMed Central

Prentice, Ross L.; Chlebowski, Rowan T.; Stefanick, Marcia L.; Manson, JoAnn E.; Langer, Robert D.; Pettinger, Mary; Hendrix, Susan L.; Hubbell, F. Allan; Kooperberg, Charles; Kuller, Lewis H.; Lane, Dorothy S.; McTiernan, Anne; O’Sullivan, Mary Jo; Rossouw, Jacques E.; Anderson, Garnet L.

2009-01-01

The Women’s Health Initiative randomized controlled trial found a trend (p = 0.09) toward a lower breast cancer risk among women assigned to daily 0.625-mg conjugated equine estrogens (CEEs) compared with placebo, in contrast to an observational literature that mostly reports a moderate increase in risk with estrogenalone preparations. In 1993–2004 at 40 US clinical centers, breast cancer hazard ratio estimates for this CEE regimen were compared between the Women’s Health Initiative clinical trial and observational study toward understanding this apparent discrepancy and refining hazard ratio estimates. After control for prior use of postmenopausal hormone therapy and for confounding factors, CEE hazard ratio estimates were higher from the observational study compared with the clinical trial by 43% (p = 0.12). However, after additional control for time from menopause to first use of postmenopausal hormone therapy, the hazard ratios agreed closely between the two cohorts (p = 0.82). For women who begin use soon after menopause, combined analyses of clinical trial and observational study data do not provide clear evidence of either an overall reduction or an increase in breast cancer risk with CEEs, although hazard ratios appeared to be relatively higher among women having certain breast cancer risk factors or a low body mass index. PMID:18448442

Alcohol Intake and Risk of Thyroid Cancer: A Meta-Analysis of Observational Studies

PubMed Central

Hong, Seung-Hee; Myung, Seung-Kwon; Kim, Hyeon Suk

2017-01-01

Purpose The purpose of this study was to assess whether alcohol intake is associated with the risk of thyroid cancer by a meta-analysis of observational studies. Materials and Methods We searched PubMed and EMBASE in June of 2015 to locate eligible studies. We included observational studies such as cross-sectional studies, case-control studies, and cohort studies reporting odd ratios (ORs) or relative risk (RRs) with 95% confidence intervals (CIs). Results We included 33 observational studies with two cross-sectional studies, 20 case-controls studies, and 11 cohort studies, which involved a total of 7,725 thyroid cancer patients and 3,113,679 participants without thyroid cancer in the final analysis. In the fixed-effect model meta-analysis of all 33 studies, we found that alcohol intake was consistently associated with a decreased risk of thyroid cancer (OR or RR, 0.74; 95% CI, 0.67 to 0.83; I2=38.6%). In the subgroup meta-analysis by type of study, alcohol intake also decreased the risk of thyroid cancer in both case-control studies (OR, 0.77; 95% CI, 0.65 to 0.92; I2=29.5%; n=20) and cohort studies (RR, 0.70; 95% CI, 0.60 to 0.82; I2=0%; n=11). Moreover, subgroup meta-analyses by type of thyroid cancer, gender, amount of alcohol consumed, and methodological quality of study showed that alcohol intake was significantly associated with a decreased risk of thyroid cancer. Conclusion The current meta-analysis of observational studies found that, unlike most of other types of cancer, alcohol intake decreased the risk of thyroid cancer. PMID:27456949

Observation of EHO in NSTX and Theoretical Study of its Active Control Using HHFW Antenna

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

J.-K. Park, et. al.

2013-01-14

Two important topics in the tokamak ELM control, using the non-axisymmetric (3D) magnetic perturbations, are studied in NSTX and combined envisioning ELM control in the future NSTX-U operation: Experimental observations of the edge harmonic oscillation in NSTX (not necessarily the same as EHOs in DIII-D), and theoretical study of its external drive using the high harmonic fast wave (HHFW) antenna as a 3D field coil. Edge harmonic oscillations were observed particularly well in NSTX ELM-free operation with low n core modes, with various diagnostics confirming n = 4 ~ 6 edge-localized and coherent oscillations in 2 ~ 8kHz frequency range.more » These oscillations seem to have a favored operational window in rotational shear, similarly to EHOs in DIII-D QH modes . However, in NSTX, they are not observed to provide particle or impurity control, possibly due to their weak amplitudes, of a few mm displacements, as measured by reflectometry. The external drive of these modes has been proposed in NSTX, by utilizing audio-frequency currents in the HHFW antenna straps. Analysis shows that the HHFW straps can be optimized to maximize n = 4 ~ 6 while minimizing n = 1 ~ 3. Also, IPEC calculations show that the optimized configuration with only 1kAt current can produce comparable or larger displacements than the observed internal modes. If this optimized external drive can be constructively combined, or further resonated with the internal modes, the edge harmonic oscillations in NSTX may be able to produce sufficient particle control to modify ELMs.« less

ERAP1 variants are associated with ankylosing spondylitis in East Asian population: a new Chinese case-control study and meta-analysis of published series.

PubMed

Chen, C; Zhang, X

2015-06-01

Endoplasmic reticulum aminopeptidase 1 (ERAP1) has been confirmed to be associated with ankylosing spondylitis (AS) in Caucasian. However, whether they are associated with AS in East Asian population remains unidentified. We investigated this relationship by a new Chinese case-control study and a meta-analysis of published series. 368 cases and 460 controls were recruited in the Chinese case-control study. Genotyping was completed using the chip-based matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Allelic associations were analysed using contingency tables. In the meta-analysis, up to 2748 cases and 2774 controls from seven different studies and the new Chinese study were combined using Review Manager software version 5.1.1. Mantel-Haenszel or Inverse Variance test was used to calculate fixed or random-effects pooled ORs. In the new Chinese study, strong association with AS was observed for marker rs10050860, rs27434 and rs1065407 at P value of <0.001. Moderate association was observed for rs30187 at P value of <0.01, while no association was observed for rs27044 (P = 0.37) and rs2287987 (P = 0.23). The meta-analysis showed that rs27037 and rs30187 were strongly associated with AS (P < 0.00001). Significant association was also observed for rs27434 (P = 0.001). No association was shown for rs27044 (P = 0.70). We concluded that ERAP1 variants are associated with AS in East Asian population, indicating a common pathogenic mechanism for AS in East Asians and Caucasians. © 2015 John Wiley & Sons Ltd.

Demonstration for Social Change: An Experiment in Local Control.

ERIC Educational Resources Information Center

Gittell, Marilyn; And Others

This evaluative history of New York City's recent experiments in public education documents three projects: Ocean Hill-Brownsville, IS 201, and Two Bridges. This study employs a process oriented and a qualitative methodology which relies most on field observation and participant-observers. The Institute study observed the new community boards,…

Contribution of spontaneous improvement to placebo response in depression: a meta-analytic review.

PubMed

Rutherford, Bret R; Mori, Shoko; Sneed, Joel R; Pimontel, Monique A; Roose, Steven P

2012-06-01

It is unknown to what degree spontaneous improvement accounts for the large placebo response observed in antidepressant trials for Major Depressive Disorder (MDD). The purpose of this study was to estimate the spontaneous improvement observed in treatment-seeking individuals with acute MDD by determining the symptom change in depressed patients assigned to wait-list controls in psychotherapy studies. The databases PubMed and PsycINFO were searched to identify randomized, prospective studies randomizing outpatients to psychotherapy or a wait-list control condition for the treatment of acute MDD. Standardized effect sizes calculated from each identified study were aggregated in a meta-analysis to obtain a summary statistic for the change in depression scores during participation in a wait-list control. Ten trials enrolling 340 participants in wait-list control conditions were identified. The estimated effect size for the change in depression scores during wait-list control was 0.505 (95% CI 0.271-0.739, p < 0.001), representing an average improvement of 4 points on the Hamilton Rating Scale for Depression. Depressed patients acutely experience improvement even without treatment, but spontaneous improvement is unlikely to account for the magnitude of placebo response typically observed in antidepressant trials. These findings must be interpreted in light of the small number wait-list control participants available for analysis as well as certain methodological heterogeneity in the psychotherapy studies analyzed. Copyright © 2012 Elsevier Ltd. All rights reserved.

Adaptive extended-state observer-based fault tolerant attitude control for spacecraft with reaction wheels

NASA Astrophysics Data System (ADS)

Ran, Dechao; Chen, Xiaoqian; de Ruiter, Anton; Xiao, Bing

2018-04-01

This study presents an adaptive second-order sliding control scheme to solve the attitude fault tolerant control problem of spacecraft subject to system uncertainties, external disturbances and reaction wheel faults. A novel fast terminal sliding mode is preliminarily designed to guarantee that finite-time convergence of the attitude errors can be achieved globally. Based on this novel sliding mode, an adaptive second-order observer is then designed to reconstruct the system uncertainties and the actuator faults. One feature of the proposed observer is that the design of the observer does not necessitate any priori information of the upper bounds of the system uncertainties and the actuator faults. In view of the reconstructed information supplied by the designed observer, a second-order sliding mode controller is developed to accomplish attitude maneuvers with great robustness and precise tracking accuracy. Theoretical stability analysis proves that the designed fault tolerant control scheme can achieve finite-time stability of the closed-loop system, even in the presence of reaction wheel faults and system uncertainties. Numerical simulations are also presented to demonstrate the effectiveness and superiority of the proposed control scheme over existing methodologies.

Antidepressant use and risk of coronary heart disease: meta-analysis of observational studies

PubMed Central

Oh, Seung-Won; Kim, Joonseok; Myung, Seung-Kwon; Hwang, Seung-Sik; Yoon, Dae-Hyun

2014-01-01

Aims Our goal was to evaluate the association between antidepressant use and the risk of coronary heart disease (CHD) among subjects with no history of coronary heart disease. Methods A search of Medline, EMBASE, PsycINFO and the Cochrane Library was performed in January 2013. Two authors independently reviewed and selected eligible observational studies, based on predetermined selection criteria. Pooled relative risks (RRs) with confidence intervals (CIs) were calculated using random-effects or fixed-effects models. Results Sixteen observational studies (seven case–control studies and nine cohort studies) were included in the final analysis. There was no association between selective serotonin reuptake inhibitor use and the risk of CHD overall [odds ratio (OR), 0.93; 95% CI, 0.65–1.33] or in subgroup meta-analysis of case–control studies (OR, 0.91; 95% CI, 0.60–1.37) and cohort studies (RR, 0.96; 95% CI, 0.59–1.55). The use of tricyclic antidepressant was associated with an increased risk of CHD overall (OR, 1.51; 95% CI, 1.07–2.12), but it was observed only in case–control studies (OR, 1.56; 95% CI, 1.24–1.96) and low-quality studies (OR, 1.49; 95% CI, 1.20–1.85) in the subgroup meta-analyses. Conclusions This meta-analysis of observational studies in subjects with no history of CHD suggests that neither selective serotonin reuptake inhibitor nor tricyclic antidepressant use is associated with an increased risk of CHD. PMID:24646010

Sliding mode disturbance observer-based control of a twin rotor MIMO system.

PubMed

Rashad, Ramy; El-Badawy, Ayman; Aboudonia, Ahmed

2017-07-01

This work proposes a robust tracking controller for a helicopter laboratory setup known as the twin rotor MIMO system (TRMS) using an integral sliding mode controller. To eliminate the discontinuity in the control signal, the controller is augmented by a sliding mode disturbance observer. The actuator dynamics is handled using a backstepping approach which is applicable due to the continuous chattering-free nature of the command signals generated using the disturbance observer based controller. To avoid the complexity of analytically differentiating the command signals, a first order sliding mode differentiator is used. Stability analysis of the closed loop system and the ultimate boundedness of the tracking error is proved using Lyapunov stability arguments. The proposed controller is validated by several simulation studies and is compared to other schemes in the literature. Experimental results using a hardware-in-the-loop system validate the robustness and effectiveness of the proposed controller. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

Event-rate and delta inflation when evaluating mortality as a primary outcome from randomized controlled trials of nutritional interventions during critical illness: a systematic review.

PubMed

Summers, Matthew J; Chapple, Lee-anne S; McClave, Stephen A; Deane, Adam M

2016-04-01

There is a lack of high-quality evidence that proves that nutritional interventions during critical illness reduce mortality. We evaluated whether power calculations for randomized controlled trials (RCTs) of nutritional interventions that used mortality as the primary outcome were realistic, and whether overestimation was systematic in the studies identified to determine whether this was due to overestimates of event rate or delta. A systematic review of the literature between 2005 and 2015 was performed to identify RCTs of nutritional interventions administered to critically ill adults that had mortality as the primary outcome. Predicted event rate (predicted mortality during the control), predicted mortality during intervention, predicted delta (predicted difference between mortality during the control and intervention), actual event rate (observed mortality during control), observed mortality during intervention, and actual delta (difference between observed mortality during the control and intervention) were recorded. The event-rate gap (predicted event rate minus observed event rate), the delta gap (predicted delta minus observed delta), and the predicted number needed to treat were calculated. Data are shown as median (range). Fourteen articles were extracted, with power calculations provided for 10 studies. The predicted event rate was 29.9% (20.0–52.4%), and the predicted delta was 7.9% (3.0–20.0%). If the study hypothesis was proven correct then, on the basis of the power calculations, the number needed to treat would have been 12.7 (5.0–33.3) patients. The actual event rate was 25.3% (6.1–50.0%), the observed mortality during the intervention was 24.4% (6.3–39.7%), and the actual delta was 0.5% (−10.2–10.3%), such that the event-rate gap was 2.6% (−3.9–23.7%) and delta gap was 7.5% (3.2–25.2%). Overestimates of delta occur frequently in RCTs of nutritional interventions in the critically ill that are powered to determine a mortality benefit. Delta inflation may explain the number of "negative" studies in this field of research.

Use of a Differential Observing Response to Expand Restricted Stimulus Control

ERIC Educational Resources Information Center

Walpole, Carrie Wallace; Roscoe, Eileen M.; Dube, William V.

2007-01-01

This study extends previous work on the use of differential observing responses (DOR) to remediate atypically restricted stimulus control. A participant with autism had high matching-to-sample accuracy scores with printed words that had no letters in common (e.g., "cat," "lid," "bug") but poor accuracy with words that had two letters in common…

Application of a sub-specialties management model improves quality control in a central sterile supply department.

PubMed

Wang, Li; Cai, Xuejiao; Cheng, Ping

2018-05-30

The management of medical devices is crucial to safe, high-quality surgical care, but has received little attention in the medical literature. This study explored the effect of a sub-specialties management model in the Central Sterile Supply Department (CSSD). A traditional routine management model (control) was applied from September 2015 through April 2016, and a newly developed sub-specialties management model (observation) was applied from July 2016 through February 2017. Health personnel from various clinical departments were randomly selected to participate as the control (n = 86) and observation (n = 90) groups, respectively. The groups were compared for rates of personnel satisfaction, complaints regarding device errors, and damage of medical devices. The satisfaction score of the observation group (95.8 ± 1.2) was significantly higher than that of the control (90.2 ± 2.3; P = 0.000). The rate of complaints of the observation group (3.3%) was significantly lower than that of the control (11.6%; P = 0.035). The quality control regarding recycle and packing was significantly higher during the observation period than the control period, which favorably influenced the scores for satisfaction. The rate of damage to specialist medical devices during the observation period (0.40%) was lower than during the control period (0.61%; P = 0.003). The theoretical knowledge and practical skills of the CSSD professionals improved after application of the sub-specialties management model. A management model that considers the requirements of specialist medical devices can improve quality control in the CSSD.

Postural Stabilization Strategies to Motor Contagion Induced by Action Observation Are Impaired in Parkinson’s Disease

PubMed Central

Pelosin, Elisa; Bisio, Ambra; Pozzo, Thierry; Lagravinese, Giovanna; Crisafulli, Oscar; Marchese, Roberta; Abbruzzese, Giovanni; Avanzino, Laura

2018-01-01

Postural reactions can be influenced by concomitant tasks or different contexts and are modulated by a higher order motor control. Recent studies investigated postural changes determined by motor contagion induced by action observation (chameleon effect) showing that observing a model in postural disequilibrium induces an increase in healthy subjects’ body sway. Parkinson’s disease (PD) is associated with postural instability and impairments in cognitively controlled balance tasks. However, no studies investigated if viewing postural imbalance might influence postural stability in PD and if patients are able to inhibit a visual postural perturbation. In this study, an action observation paradigm for assessing postural reaction to motor contagion in PD subjects and healthy older adults was used. Postural stability changes were measured during the observation of a static stimulus (control condition) and during a point-light display of a gymnast balancing on a rope (biological stimulus). Our results showed that, during the observation of the biological stimulus, sway area and antero-posterior and medio-lateral displacements of center of pressure significantly increased only in PD participants, whereas correct stabilization reactions were present in elderly subjects. These results demonstrate that PD leads to a decreased capacity to control automatic imitative tendencies induced by motor contagion. This behavior could be the consequence either of an inability to inhibit automatic imitative tendencies or of the cognitive load requested by the task. Whatever the case, the issue about the ability to inhibit automatic imitative tendencies could be crucial for PD patients since it might increase falls risk and injuries. PMID:29545771

The influence of interferon β-1b on gut microbiota composition in patients with multiple sclerosis.

PubMed

Castillo-Álvarez, F; Pérez-Matute, P; Oteo, J A; Marzo-Sola, M E

2018-06-09

The association between gut microbiota and animal models of multiple sclerosis has been well established; however, studies in humans are scarce. We performed a descriptive, cross-sectional study comparing the relative composition of gut microbiota in 30 patients with multiple sclerosis (15 treated with interferon β-1b, 15 not receiving this treatment) and 14 healthy controls using next generation sequencing. Patients with multiple sclerosis and controls showed differences in the proportion of Euryarchaeota, Firmicutes, Proteobacteria, Actinobacteria, and Lentisphaerae phyla and in 17 bacterial species. More specifically, we found significant differences in the proportion of Firmicutes, Actinobacteria, and Lentisphaerae and 6 bacteria species between controls and untreated patients; however, these differences disappeared when compared with treated patients. Untreated patients showed a significant reduction in the proportion of Prevotella copri compared to controls, while the bacteria was significantly more abundant in patients treated with interferon β-1b than in untreated patients, with levels resembling those observed in the healthy control group. We observed differences in gut microbiota composition between patients with multiple sclerosis and controls, and between patients treated and not treated with interferon β-1b. In most cases, no differences were observed between treated patients and healthy controls, particularly for P. copri levels. This suggests that the clinical improvements observed in patients with multiple sclerosis receiving interferon β-1b may result from the effect of the drug on gut microbiota. Longitudinal and functional studies are necessary to establish a causal relationship. Copyright © 2018 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

Exposure reduces negative bias in self-rated performance in public speaking fearful participants.

PubMed

Cheng, Joyce; Niles, Andrea N; Craske, Michelle G

2017-03-01

Individuals with public speaking anxiety (PSA) under-rate their performance compared to objective observers. The present study examined whether exposure reduces the discrepancy between self and observer performance ratings and improved observer-rated performance in individuals with PSA. PSA participants gave a speech in front of a small audience and rated their performance using a questionnaire before and after completing repeated exposures to public speaking. Non-anxious control participants gave a speech and completed the questionnaire one time only. Objective observers watched videos of the speeches and rated performance using the same questionnaire. PSA participants underrated their performance to a greater degree than did controls prior to exposure, but also performed significantly more poorly than did controls when rated objectively. Bias significantly decreased and objective-rated performance significantly increased following completion of exposure in PSA participants, and on one performance measure, anxious participants no longer showed a greater discrepancy between self and observer performance ratings compared to controls. The study employed non-clinical student sample, but the results should be replicated in clinical anxiety samples. These findings indicate that exposure alone significantly reduces negative performance bias among PSA individuals, but additional exposure or additional interventions may be necessary to fully correct bias and performance deficits. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Integration of Negative Affect, Pain, and Cognitive Control in the Cingulate Cortex

PubMed Central

Shackman, Alexander J.; Salomons, Tim V.; Slagter, Heleen A.; Fox, Andrew S.; Winter, Jameel J.; Davidson, Richard J.

2011-01-01

Preface It has been argued that emotion, pain, and cognitive control are functionally segregated in distinct subdivisions of the cingulate cortex. But recent observations encourage a fundamentally different view. Imaging studies indicate that negative affect, pain, and cognitive control activate an overlapping region of dorsal cingulate, the anterior midcingulate cortex (aMCC). Anatomical studies reveal that aMCC constitutes a hub where information about reinforcers can be linked to motor centers responsible for expressing affect and executing goal-directed behavior. Computational modeling and other kinds of evidence suggest that this intimacy reflects control processes that are common to all three domains. These observations compel a reconsideration of dorsal cingulate’s contribution to negative affect and pain. PMID:21331082

Height Accuracy Based on Different Rtk GPS Method for Ultralight Aircraft Images

NASA Astrophysics Data System (ADS)

Tahar, K. N.

2015-08-01

Height accuracy is one of the important elements in surveying work especially for control point's establishment which requires an accurate measurement. There are many methods can be used to acquire height value such as tacheometry, leveling and Global Positioning System (GPS). This study has investigated the effect on height accuracy based on different observations which are single based and network based GPS methods. The GPS network is acquired from the local network namely Iskandar network. This network has been setup to provide real-time correction data to rover GPS station while the single network is based on the known GPS station. Nine ground control points were established evenly at the study area. Each ground control points were observed about two and ten minutes. It was found that, the height accuracy give the different result for each observation.

An Introduction to Propensity Score Methods for Reducing the Effects of Confounding in Observational Studies

ERIC Educational Resources Information Center

Austin, Peter C.

2011-01-01

The propensity score is the probability of treatment assignment conditional on observed baseline characteristics. The propensity score allows one to design and analyze an observational (nonrandomized) study so that it mimics some of the particular characteristics of a randomized controlled trial. In particular, the propensity score is a balancing…

Benchmarking Controlled Trial—a novel concept covering all observational effectiveness studies

PubMed Central

Malmivaara, Antti

2015-01-01

Abstract The Benchmarking Controlled Trial (BCT) is a novel concept which covers all observational studies aiming to assess effectiveness. BCTs provide evidence of the comparative effectiveness between health service providers, and of effectiveness due to particular features of the health and social care systems. BCTs complement randomized controlled trials (RCTs) as the sources of evidence on effectiveness. This paper presents a definition of the BCT; compares the position of BCTs in assessing effectiveness with that of RCTs; presents a checklist for assessing methodological validity of a BCT; and pilot-tests the checklist with BCTs published recently in the leading medical journals. PMID:25965700

Control of Aedes aegypti Breeding: A Novel Intervention for Prevention and Control of Dengue in an Endemic Zone of Delhi, India

PubMed Central

Nagpal, B. N.; Gupta, Sanjeev Kumar; Shamim, Arshad; Vikram, Kumar; Srivastava, Aruna; Tuli, N. R.; Saxena, Rekha; Singh, Himmat; Singh, V. P.; Bhagat, V. N.; Yadav, N. K.; Valecha, Neena

2016-01-01

Background and objective The study is based on hypothesis that whether continuous entomological surveillance of Ae. aegypti and simultaneous appropriate interventions in key containers during non-transmission (December–May) months would have any impact on breeding of Aedes and dengue cases during the following transmission months (June–November). The impact of the surveillance and intervention measures undertaken during non-transmission months were assessed by entomological indicators namely container index (CI), house index (HI), pupal index (PI) and breteau index (BI). Methods A total of 28 localities of West Zone of Delhi with persistent dengue endemicity were selected for the study. Out of these localities, 20 were included in study group while other 8 localities were in control group. IEC and various Aedes breeding control activities were carried out in study group in both non-transmission and transmission season whereas control group did not have any such interventions during non-transmission months as per guidelines of MCD. These activities were undertaken by a team of investigators from NIMR and SDMC, Delhi. In control group, investigators from NIMR carried out surveillance activity to monitor the breeding of Aedes mosquito in localities. Results Comparison of baseline data revealed that all indices in control and study group of localities were comparable and statistically non-significant (p>0.05). In both study and control groups, indices were calculated after pooling data on seasonal basis, i.e., transmission and non-transmission months for both years. The test of significance conducted on all the four indices, i.e., HI, PI, CI, and BI, revealed a significant difference (p<0.05) between the study group and control group during transmission and non-transmission months except in HI. Due to consistent intervention measures undertaken in non-transmission months in study group, reduction in CI, HI, BI and PI was observed 63%, 62%, 64% and 99% respectively during transmission months as compared to control group where increase of 59%, 102%, 73% and 71% respectively. As a result of reduction in larval indices, no dengue case (except one NS1) was observed in study group, whereas 38 dengue cases were observed in control group. Conclusion Through this pilot study, it is concluded that proper intervention in non-transmission season reduces vector density and subsequently dengue cases in transmission season. PMID:27918577

Control of Aedes aegypti Breeding: A Novel Intervention for Prevention and Control of Dengue in an Endemic Zone of Delhi, India.

PubMed

Nagpal, B N; Gupta, Sanjeev Kumar; Shamim, Arshad; Vikram, Kumar; Srivastava, Aruna; Tuli, N R; Saxena, Rekha; Singh, Himmat; Singh, V P; Bhagat, V N; Yadav, N K; Valecha, Neena

2016-01-01

The study is based on hypothesis that whether continuous entomological surveillance of Ae. aegypti and simultaneous appropriate interventions in key containers during non-transmission (December-May) months would have any impact on breeding of Aedes and dengue cases during the following transmission months (June-November). The impact of the surveillance and intervention measures undertaken during non-transmission months were assessed by entomological indicators namely container index (CI), house index (HI), pupal index (PI) and breteau index (BI). A total of 28 localities of West Zone of Delhi with persistent dengue endemicity were selected for the study. Out of these localities, 20 were included in study group while other 8 localities were in control group. IEC and various Aedes breeding control activities were carried out in study group in both non-transmission and transmission season whereas control group did not have any such interventions during non-transmission months as per guidelines of MCD. These activities were undertaken by a team of investigators from NIMR and SDMC, Delhi. In control group, investigators from NIMR carried out surveillance activity to monitor the breeding of Aedes mosquito in localities. Comparison of baseline data revealed that all indices in control and study group of localities were comparable and statistically non-significant (p>0.05). In both study and control groups, indices were calculated after pooling data on seasonal basis, i.e., transmission and non-transmission months for both years. The test of significance conducted on all the four indices, i.e., HI, PI, CI, and BI, revealed a significant difference (p<0.05) between the study group and control group during transmission and non-transmission months except in HI. Due to consistent intervention measures undertaken in non-transmission months in study group, reduction in CI, HI, BI and PI was observed 63%, 62%, 64% and 99% respectively during transmission months as compared to control group where increase of 59%, 102%, 73% and 71% respectively. As a result of reduction in larval indices, no dengue case (except one NS1) was observed in study group, whereas 38 dengue cases were observed in control group. Through this pilot study, it is concluded that proper intervention in non-transmission season reduces vector density and subsequently dengue cases in transmission season.

A systematic literature review on the efficacy–effectiveness gap: comparison of randomized controlled trials and observational studies of glucose-lowering drugs

PubMed Central

Ankarfeldt, Mikkel Z; Adalsteinsson, Erpur; Groenwold, Rolf HH; Ali, M Sanni; Klungel, Olaf H

2017-01-01

Aim To identify a potential efficacy–effectiveness gap and possible explanations (drivers of effectiveness) for differences between results of randomized controlled trials (RCTs) and observational studies investigating glucose-lowering drugs. Methods A systematic literature review was conducted in English language articles published between 1 January, 2000 and 31 January, 2015 describing either RCTs or observational studies comparing glucagon-like peptide-1 analogs (GLP-1) with insulin or comparing dipeptidyl peptidase-4 inhibitors (DPP-4i) with sulfonylurea, all with change in glycated hemoglobin (HbA1c) as outcome. Medline, Embase, Current Content, and Biosis were searched. Information on effect estimates, baseline characteristics of the study population, publication year, study duration, and number of patients, and for observational studies, characteristics related to confounding adjustment and selection- and information bias were extracted. Results From 312 hits, 11 RCTs and 7 observational studies comparing GLP-1 with insulin, and from 474 hits, 16 RCTs and 4 observational studies comparing DPP-4i with sulfonylurea were finally included. No differences were observed in baseline characteristics of the study populations (age, sex, body mass index, time since diagnosis of type 2 diabetes mellitus, and HbA1c) or effect sizes across study designs. Mean effect sizes ranged from −0.43 to 0.91 and from −0.80 to 1.13 in RCTs and observational studies, respectively, comparing GLP-1 with insulin, and from −0.13 to 2.70 and −0.20 to 0.30 in RCTs and observational studies, respectively, comparing DPP-4i and sulfonylurea. Generally, the identified observational studies held potential flaws with regard to confounding adjustment and selection- and information bias. Conclusions Neither potential drivers of effectiveness nor an efficacy–effectiveness gap were identified. However, the limited number of studies and potential problems with confounding adjustment, selection- and information bias in the observational studies, may have hidden a true efficacy-effectiveness gap. PMID:28176959

Overview of clinical research design.

PubMed

Hartung, Daniel M; Touchette, Daniel

2009-02-15

Basic concepts and terminology of clinical research design are presented for new clinical investigators. Clinical research, research involving human subjects, can be described as either observational or experimental. The findings of all clinical research can be threatened by issues of bias and confounding. Biases are systematic errors in how study subjects are selected or measured, which result in false inferences. Confounding is a distortion in findings that is attributable to mixing variable effects. Uncontrolled observation research is generally more prone to bias and confounding than experimental research. Observational research includes designs such as the cohort study, case-control study, and cross-sectional study, while experimental research typically involves a randomized controlled trial (RCT). The cohort study, which includes the RCT, defines subject allocation on the basis of exposure interest (e.g., drug, disease-management program) and follows the patients to assess the outcomes. The case-control study uses the primary outcome of interest (e.g., adverse event) to define subject allocation, and different exposures are assessed in a retrospective manner. Cross-sectional research evaluates both exposure and outcome concurrently. Each of these design methods possesses different strengths and weaknesses in answering research questions, as well as underlying many study subtypes. While experimental research is the strongest method for establishing causality, it can be difficult to accomplish under many scenarios. Observational clinical research offers many design alternatives that may be appropriate if planned and executed carefully.

Analysis of reportable events in Kansas City air route traffic control center

DOT National Transportation Integrated Search

2017-02-10

The implementation of ControllerPilot Datalink Communications (CPDLC) in domestic en route airspace will change the controllers and pilots : tasks, which will, in turn change the types of observed errors. This study characterizes the current...

A cluster design controlled trial of arts-based observational skills training in primary care.

PubMed

Kirklin, Deborah; Duncan, Jane; McBride, Sandy; Hunt, Sam; Griffin, Mark

2007-04-01

To investigate whether the observational skills of doctors and nurses can be improved by arts-based observational skills training. We carried out a cluster design, controlled trial involving 42 general practitioners and 26 primary care nurses in 12 primary care practices in London. Six practices were allocated to the intervention arm and 6 to the control arm. The intervention group received 90 minutes of arts-based observational skills training. The control group received practical training in the management of psoriasis. Before and after this, control and intervention participants were asked to describe 3 dermatological photographs. Descriptions were scored blindly against a predetermined marking key. Participants completed a questionnaire about the intervention, and about their own confidence in diagnosing and referring suspicious pigmented skin lesions. Post-intervention scores were significantly higher in the intervention group compared with the control group (P < 0.001). The majority of participants judged the intervention relevant, enjoyable and valuable. A majority lacked confidence in their dermatological knowledge and skills. This study provides statistically significant evidence that arts-based observational skills training can improve the observational skills of doctors and nurses. It is important not to overstate the clinical significance of these findings, and to recognise that observational skills are just one of many complex and subtle factors affecting the quality of the clinical process. Further research is needed to assess the existence, nature and clinical significance of longer-term benefits, and to identify differences between professional groups.

Effect of edge pruning on structural controllability and observability of complex networks

PubMed Central

Mengiste, Simachew Abebe; Aertsen, Ad; Kumar, Arvind

2015-01-01

Controllability and observability of complex systems are vital concepts in many fields of science. The network structure of the system plays a crucial role in determining its controllability and observability. Because most naturally occurring complex systems show dynamic changes in their network connectivity, it is important to understand how perturbations in the connectivity affect the controllability of the system. To this end, we studied the control structure of different types of artificial, social and biological neuronal networks (BNN) as their connections were progressively pruned using four different pruning strategies. We show that the BNNs are more similar to scale-free networks than to small-world networks, when comparing the robustness of their control structure to structural perturbations. We introduce a new graph descriptor, ‘the cardinality curve’, to quantify the robustness of the control structure of a network to progressive edge pruning. Knowing the susceptibility of control structures to different pruning methods could help design strategies to destroy the control structures of dangerous networks such as epidemic networks. On the other hand, it could help make useful networks more resistant to edge attacks. PMID:26674854

The effect of exposure of rats during prenatal period to radiation spreading from mobile phones on renal development.

PubMed

Bedir, Recep; Tumkaya, Levent; Şehitoğlu, İbrahim; Kalkan, Yıldıray; Yilmaz, Adnan; Şahin, Osman Zikrullah

2015-03-01

The aim of this study was to investigate the effects of exposure to a 900-MHz electromagnetic field (EMF) produced by mobile phones on the renal development of prenatal rats. Histopathological changes and apoptosis in the kidneys, together with levels of urea, creatinine and electrolyte in serum were determined. A total of 14 Sprague-Dawley rats were studied. Pregnant rats were divided into two equal groups: a control group and an EMF-exposed group. The study group was exposed to 900-MHz of EMF during the first 20 days of pregnancy, while the control group was unexposed to EMF. Sections obtained from paraffin blocks were stained for caspase-3 by immunohistochemistry, hematoxylin-eosin and Masson's trichrome. Mild congestion and tubular defects, and dilatation of Bowman's capsule were observed in the kidney tissues of rats in the exposed group. Apoptosis was evaluated using anti-caspase-3; stronger positive staining was observed in the renal tubular cells in the study group than those of the control group. Although there was a significant difference between the study and control groups in terms of K+ level (p<0.05), no significant difference was observed in the other parameters studied (p>0.05). Our study shows that the electromagnetic waves propagated from mobile phones have harmful effects on the renal development of prenatal rats.

Landscape control points: a procedure for predicting and monitoring visual impacts

Treesearch

R. Burton Litton

1973-01-01

The visual impacts of alterations to the landscape can be studied by setting up Landscape Control Points–a network of permanently established observation sites. Such observations enable the forest manager to anticipate visual impacts of management decision, select from a choice of alternative solutions, cover an area for comprehensive viewing, and establish a method to...

The Observation of Manual Grasp Actions Affects the Control of Speech: A Combined Behavioral and Transcranial Magnetic Stimulation Study

ERIC Educational Resources Information Center

Gentilucci, Maurizio; Campione, Giovanna Cristina; Volta, Riccardo Dalla; Bernardis, Paolo

2009-01-01

Does the mirror system affect the control of speech? This issue was addressed in behavioral and Transcranial Magnetic Stimulation (TMS) experiments. In behavioral experiment 1, participants pronounced the syllable /da/ while observing (1) a hand grasping large and small objects with power and precision grasps, respectively, (2) a foot interacting…

Jet-lag: prevention with Pycnogenol. Preliminary report: evaluation in healthy individuals and in hypertensive patients.

PubMed

Belcaro, G; Cesarone, M R; Steigerwalt, R J; Di Renzo, A; Grossi, M G; Ricci, A; Stuard, S; Ledda, A; Dugall, M; Cornelli, U; Cacchio, M

2008-10-01

This study was conducted with the aim of showing the effects of Pycnogenol on controlling jet-lag symptoms. Oral Pycnogenol, 50 mg tablets 3 times/die, for 7 days starting 2 days prior to the flight was used. The study was divided into two separate parts. In study 1 the most common complaints of patients with jet-lag were evaluated with a rating scale consisting in of a scoring system. In study 2 a brain CT scan was performed after the flight in order to assess minimal brain edema (MBE) in association with typical signs and symptoms, observed in previous published flight studies. Study one included 38 subjects treated with Pycnogenol and 30 controls. The symptomatic jet-lag related total score was significantly lower (indicating a lower level of jet-lag) in the Pycnogenol group. The average duration of any jet lag symptom following the flight was significantly reduced from 39.3 (SD=0.8) hours in controls to an average of 18.2 (SD=3.3) hours in the Pycnogenol group (P<0.05). Study 2 included 34 subjects treated with Pycnogenol and 31 controls. The main observation was the brain CT scan performed within 28 hours after the end of the flight. The difference between the Pycnogenol and the control groups was statistically significant (P<0.05) for all items assessed including the cerebral edema score obtained by CT scan. The short-term memory was significantly altered in the control group and associated to edema and swelling of the lower limbs. The score (and the level of edema) was comparatively higher in a subgroup of hypertensive subjects in the control group. Minor alterations of cardiac function were observed in association with de-stabilisation of blood pressure. Fatigue was also significantly higher in the control group in comparison with the Pycnogenol group. A number of spontaneously reported symptoms was also scored and there was a statistically significant difference (P<0.05) between the Pycnogenol and control groups. In conlusion, Pycnogenol was useful to control jet-lag and minimal brain edema.

Traffic-Related Air Pollution and Childhood Acute Leukemia in Oklahoma

PubMed Central

Janitz, Amanda E.; Campbell, Janis E.; Magzamen, Sheryl; Pate, Anne; Stoner, Julie A.; Peck, Jennifer D.

2016-01-01

Background While many studies have evaluated the association between acute childhood leukemia and environmental factors, knowledge is limited. Ambient air pollution has been classified as a Group 1 carcinogen, but studies have not established whether traffic-related air pollution is associated with leukemia. The goal of our study was to determine if children with acute leukemia had higher odds of exposure to traffic-related air pollution at birth compared to controls. Methods We conducted a case-control study using the Oklahoma Central Cancer Registry to identify cases of acute leukemia in children diagnosed before 20 years of age between 1997 and 2012 (n=307). Controls were selected from birth certificates and matched to cases on week of birth (n=1,013). Using a novel satellite-based land-use regression model of nitrogen dioxide (NO2) and estimating road density based on the 2010 US Census, we evaluated the association between traffic-related air pollution and childhood leukemia using conditional logistic regression. Results The odds of exposure to the fourth quartile of NO2 (11.19–19.89 ppb) were similar in cases compared to controls after adjustment for maternal education (OR: 1.08, 95% CI: 0.75, 1.55). These estimates were stronger among children with acute myeloid leukemia (AML) than acute lymphoid leukemia, with a positive association observed among urban children with AML (4th quartile odds ratio: 5.25, 95% confidence interval: 1.09, 25.26). While we observed no significant association with road density, male cases had an elevated odds of exposure to roads at 500 m from the birth residence compared to controls (OR: 1.39, 95% CI: 0.93, 2.10), which was slightly attenuated at 750 m. Conclusions Although we observed no association overall between NO2 or road density, this was the first study to observe an elevated odds of exposure to NO2 among children with AML compared to controls suggesting further exploration of traffic-related air pollution and AML is warranted. PMID:27038831

Duration of immunity of a multivalent (DHPPi/L4R) canine vaccine against four Leptospira serovars.

PubMed

Wilson, Stephen; Stirling, Catrina; Thomas, Anne; King, Vickie; Plevová, Edita; Chromá, Ludmila; Siedek, Elisabeth; Illambas, Joanna; Salt, Jeremy; Sture, Gordon

2013-06-28

Despite effective vaccines against common Leptospira serovars, the development of new products with long duration of immunity is still important to protect dogs against leptospirosis. The results from four challenge studies performed one year after vaccination of dogs with a multivalent vaccine containing four Leptospira antigens are reported. Six week old dogs received two vaccinations, three weeks apart, and were challenged 367 days later. Clinical observations were recorded, while blood (culture, biochemistry and haematology), urine (culture) and liver and kidney (culture) samples were collected throughout the study or at necropsy. All control dogs remained seronegative until challenge, when they seroconverted. Antibody titres to Leptospira antigens were seen in vaccinated dogs 21 days after first vaccination and peaked three to six weeks after the second vaccination. Titres decreased in all studies over the following 12 months, until challenge when anamnestic responses were observed. In all studies control dogs demonstrated various abnormal clinical signs, while no vaccinated dogs were affected; differences between groups were only significant following L. bratislava challenge. Analysis of blood cultures showed all control and five of the 24 vaccinated dogs were Leptospira positive after challenge; all studies showed significant differences between treatment groups in mean number of days with positive cultures. Significant differences between vaccinated and control groups in mean number of days with positive urine cultures were also observed, with all non-vaccinated and one vaccinated dog Leptospira positive. The urine culture positive vaccinated dog also gave positive culture from kidney and liver samples. All except one control dog also showed positive Leptospira isolation from kidney or liver, with significant differences between vaccinated and control groups observed. The results demonstrate that administration of a new vaccine to six week old puppies induces immunity which is still effective up to one year later as demonstrated by challenge. Copyright © 2013 Elsevier Ltd. All rights reserved.

Threat facilitates subsequent executive control during anxious mood.

PubMed

Birk, Jeffrey L; Dennis, Tracy A; Shin, Lisa M; Urry, Heather L

2011-12-01

Dual competition framework (DCF) posits that low-level threat may facilitate behavioral performance by influencing executive control functions. Anxiety is thought to strengthen this effect by enhancing threat's affective significance. To test these ideas directly, we examined the effects of low-level threat and experimentally induced anxiety on one executive control function, the efficiency of response inhibition. In Study 1, briefly presented stimuli that were mildly threatening (i.e., fearful faces) relative to nonthreatening (i.e., neutral faces) led to facilitated executive control efficiency during experimentally induced anxiety. No such effect was observed during an equally arousing, experimentally induced happy mood state. In Study 2, we assessed the effects of low-level threat, experimentally induced anxiety, and individual differences in trait anxiety on executive control efficiency. Consistent with Study 1, fearful relative to neutral faces led to facilitated executive control efficiency during experimentally induced anxiety. No such effect was observed during an experimentally induced neutral mood state. Moreover, individual differences in trait anxiety did not moderate the effects of threat and anxiety on executive control efficiency. The findings are partially consistent with the predictions of DCF in that low-level threat improved executive control, at least during a state of anxiety. (c) 2011 APA, all rights reserved.

Investigation on sense of control parameters for joystick interface in remote operated container crane application

NASA Astrophysics Data System (ADS)

Abdullah, U. N. N.; Handroos, H.

2017-09-01

Introduction: This paper presents the study of sense of control parameters to improve the lack of direct motion feeling through remote operated container crane station (ROCCS) joystick interface. The investigations of the parameters in this study are important to develop the engineering parameters related to the sense of control goal in the next design process. Methodology: Structured interviews and observations were conducted to obtain the user experience data from thirteen remote container crane operators from two international terminals. Then, interview analysis, task analysis, activity analysis and time line analysis were conducted to compare and contrast the results from interviews and observations. Results: Four experience parameters were identified to support the sense of control goal in the later design improvement of the ROCC joystick interface. The significance of difficulties to control, unsynchronized movements, facilitate in control and decision making in unexpected situation as parameters to the sense of control goal were validated by' feedbacks from operators as well as analysis. Contribution: This study provides feedback directly from end users towards developing a sustainable control interface for ROCCS in specific and remote operated off-road vehicles in general.

Interpreting observational studies: why empirical calibration is needed to correct p-values

PubMed Central

Schuemie, Martijn J; Ryan, Patrick B; DuMouchel, William; Suchard, Marc A; Madigan, David

2014-01-01

Often the literature makes assertions of medical product effects on the basis of ‘ p < 0.05’. The underlying premise is that at this threshold, there is only a 5% probability that the observed effect would be seen by chance when in reality there is no effect. In observational studies, much more than in randomized trials, bias and confounding may undermine this premise. To test this premise, we selected three exemplar drug safety studies from literature, representing a case–control, a cohort, and a self-controlled case series design. We attempted to replicate these studies as best we could for the drugs studied in the original articles. Next, we applied the same three designs to sets of negative controls: drugs that are not believed to cause the outcome of interest. We observed how often p < 0.05 when the null hypothesis is true, and we fitted distributions to the effect estimates. Using these distributions, we compute calibrated p-values that reflect the probability of observing the effect estimate under the null hypothesis, taking both random and systematic error into account. An automated analysis of scientific literature was performed to evaluate the potential impact of such a calibration. Our experiment provides evidence that the majority of observational studies would declare statistical significance when no effect is present. Empirical calibration was found to reduce spurious results to the desired 5% level. Applying these adjustments to literature suggests that at least 54% of findings with p < 0.05 are not actually statistically significant and should be reevaluated. © 2013 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd. PMID:23900808

In vitro test of external Qigong

PubMed Central

Yount, Garret; Solfvin, Jerry; Moore, Dan; Schlitz, Marilyn; Reading, Melissa; Aldape, Ken; Qian, Yifang

2004-01-01

Background Practitioners of the alternative medical practice 'external Qigong' generally claim the ability to emit or direct "healing energy" to treat patients. We investigated the ability of experienced Qigong practitioners to enhance the healthy growth of cultured human cells in a series of studies, each following a rigorously designed protocol with randomization, blinding and controls for variability. Methods Qigong practitioners directed healing intentionality toward normal brain cell cultures in a basic science laboratory. Qigong treatments were delivered for 20 minutes from a minimum distance of 10 centimeters. Cell proliferation was measured by a standard colony-forming efficiency (CFE) assay and a CFE ratio (CFE for treated samples/CFE for sham samples) was the dependent measure for each experiment. Results During a pilot study (8 experiments), a trend of increased cell proliferation in Qigong-treated samples (CFE Qigong/sham ratios > 1.0) was observed (P = 0.162). In a formal study (28 experiments), a similar trend was observed, with Qigong-treated samples showing on average more colony formation than sham samples (P = 0.036). In a replication study (60 experiments), no significant difference between Qigong-treated samples and sham samples was observed (P = 0.465). Conclusion We observed an apparent increase in the proliferation of cultured cells following external Qigong treatment by practitioners under strictly controlled conditions, but we did not observe this effect in a replication study. These results suggest the need for more controlled and thorough investigation of external Qigong before scientific validation is claimed. PMID:15102336

Are Common Skin Diseases among Norwegian Dermatological Outpatients Associated with Psychological Problems Compared with Controls? An Observational Study.

PubMed

Balieva, Flora; Lien, Lars; Kupfer, Jörg; Halvorsen, Jon Anders; Dalgard, Florence

2016-02-01

Dermatological disease has been shown to be associated with psychological comorbidity. The aim of this observational study is to describe the distribution of skin disease and the prevalence of depression, anxiety and stress among Norwegian dermatological outpatients. Thirteen percent of outpatients had clinical anxiety compared with 3.7% of healthy controls, and 5.8% had clinical depression compared with 0.9% of controls. Adjusted odds ratio for clinical anxiety was 4.53 in patients compared with controls, and for clinical depression 6.25, which is much higher than previously described in a larger European study. Patients with tumours had less depression. Chronic inflammatory skin conditions had an especially high impact on patient's psychological wellbeing and should not be undervalued relative to, for instance, skin cancer in health strategies. These results argue strongly for including skin disease prevention and treatment in future health strategies.

Clinically observed chickenpox and the risk of childhood-onset multiple sclerosis.

PubMed

Mikaeloff, Yann; Caridade, Guillaume; Suissa, Samy; Tardieu, Marc

2009-05-15

The authors conducted a population-based case-control study to investigate whether clinically observed chickenpox, linked with a level of intensity for clinical expression, increases the risk of multiple sclerosis (MS) in childhood. The cases were MS patients whose disease onset occurred between 1994 and 2003, before age 16 years, in France. Each case was matched for age, sex, and geographic origin with as many as 12 controls randomly selected from the general population. Information about clinically observed chickenpox in cases and controls before the index date regarding onset of MS was collected with a standardized questionnaire and was checked against health certificates. Conditional logistic regression was used to estimate the odds ratio for an association between MS and chickenpox. The 137 MS cases were matched with 1,061 controls. Clinically observed chickenpox had occurred in 76.6% of the cases and 84.9% of their matched controls. The adjusted odds ratio of MS onset associated with chickenpox occurrence was 0.58 (95% confidence interval: 0.36, 0.92). The authors concluded that clinically observed chickenpox was associated with a lower risk of childhood-onset MS in a French population.

Clinical Efficacy of Low Molecular Heparin on Unexplained Recurrent Spontaneous Abortion.

PubMed

Xu, Guang-Li; Hu, Xiao-Fang; Han, Yong-Mei; Wei, Ai-Wu

2018-06-01

To study the clinical effect of low molecular heparin on unexplained recurrent spontaneous abortion (URSA). A total of 120 URSA patients were collected in our hospital from October 2015 to September 2017. They were divided into two groups: control group (n = 60) and observation group (n = 60). The patients in the control group were administered with progesterone and human chorionic gonadotropin, and the observation group with low molecular heparin. Pregnancy outcomes, incidence of complications in pregnancy and adverse drug reactions were compared in the two groups. The pregnancy success rate of patients in the observation group (90.00%) is higher than that in the control group (68.33%) (p < 0.05). The incidence of complications in pregnancy in the observation group (90.00%) is lower than those in the control group (68.33%) (p < 0.05). The incidence of adverse drug reactions between the patients in the observation group (20.00%) and those in the control group (23.33%) showed no significant difference (p > 0.05). Low molecular heparin treatment can improve pregnancy success rate and reduce the incidence of complications in the URSA patients. Low molecular heparin is characterized by safety and reliability and has potential for application in clinic.

Early vasopressor use following traumatic injury: a systematic review

PubMed Central

Hylands, Mathieu; Toma, Augustin; Beaudoin, Nicolas; Frenette, Anne Julie; D’Aragon, Frédérick; Belley-Côté, Émilie; Charbonney, Emmanuel; Møller, Morten Hylander; Laake, Jon Henrik; Vandvik, Per Olav; Siemieniuk, Reed Alexander; Rochwerg, Bram; Lauzier, François; Green, Robert S; Ball, Ian; Scales, Damon; Murthy, Srinivas; Kwong, Joey S W; Guyatt, Gordon; Rizoli, Sandro; Asfar, Pierre; Lamontagne, François

2017-01-01

Objectives Current guidelines suggest limiting the use of vasopressors following traumatic injury; however, wide variations in practice exist. Although excessive vasoconstriction may be harmful, these agents may help reduce administration of potentially harmful resuscitation fluids. This systematic review aims to compare early vasopressor use to standard resuscitation in adults with trauma-induced shock. Design Systematic review. Data sources We searched MEDLINE, EMBASE, ClinicalTrials.gov and the Central Register of Controlled Trials from inception until October 2016, as well as the proceedings of 10 relevant international conferences from 2005 to 2016. Eligibility criteria for selecting studies Randomised controlled trials and controlled observational studies that compared the early vasopressor use with standard resuscitation in adults with acute traumatic injury. Results Of 8001 citations, we retrieved 18 full-text articles and included 6 studies (1 randomised controlled trial and 5 observational studies), including 2 published exclusively in abstract form. Across observational studies, vasopressor use was associated with increased short-term mortality, with unadjusted risk ratios ranging from 2.31 to 7.39. However, the risk of bias was considered high in these observational studies because patients who received vasopressors were systematically sicker than patients treated without vasopressors. One clinical trial (n=78) was too imprecise to yield meaningful results. Two clinical trials are currently ongoing. No study measured long-term quality of life or cognitive function. Conclusions Existing data on the effects of vasopressors following traumatic injury are of very low quality according to the Grading of Recommendations, Assessment, Development and Evaluation methodology. With emerging evidence of harm associated with aggressive fluid resuscitation and, in selected subgroups of patients, with permissive hypotension, the alternatives to vasopressor therapy are limited. Observational data showing that vasopressors are part of usual care would provide a strong justification for high-quality clinical trials of early vasopressor use during trauma resuscitation. Trial registration number CRD42016033437. PMID:29151048

Indirect and direct perceived behavioral control and the role of intention in the context of birth control behavior.

PubMed

Hanson, Jessica D; Nothwehr, Faryle; Yang, Jingzhen Ginger; Romitti, Paul

2015-07-01

Unintended pregnancies can have negative consequences for both mother and child. The focus of this study was to utilize perceived behavioral control measures (PBC; part of the theory of planned behavior) to identify relevant behavioral determinants of birth control use. This study also tested associations between direct and indirect PBC measures and intention of birth control use and between intention and birth control use. The methods included a randomly selected sample of patients at a health care system in the Upper Midwest who were sent a self-administered survey, with 190 non-pregnant women returning completed surveys. Participants indicated a high level of control over using birth control, and a significant positive correlation was observed between direct and indirect PBC measures. Participants also reported high intentions to use birth control, and a significant positive correlation was observed between intention and PBC. Additionally, both PBC measures and intention were independently and significantly associated with behavior, and PBC remained significantly associated with behavior when intention was added into the model. In conclusion, compared to the previous literature, this study is unique in that it examines indirect PBC measures and also the important role that PBC plays with actual birth control behavior.

Indirect and Direct Perceived Behavioral Control and the Role of Intention in the Context of Birth Control Behavior

PubMed Central

Nothwehr, Faryle; Yang, Jingzhen Ginger; Romitti, Paul

2018-01-01

Unintended pregnancies can have negative consequences for both mother and child. The focus of this study was to utilize perceived behavioral control measures (PBC; part of the theory of planned behavior) to identify relevant behavioral determinants of birth control use. This study also tested associations between direct and indirect PBC measures and intention of birth control use and between intention and birth control use. The methods included a randomly selected sample of patients at a health care system in the Upper Midwest who were sent a self-administered survey, with 190 non-pregnant women returning completed surveys. Participants indicated a high level of control over using birth control, and a significant positive correlation was observed between direct and indirect PBC measures. Participants also reported high intentions to use birth control, and a significant positive correlation was observed between intention and PBC. Additionally, both PBC measures and intention were independently and significantly associated with behavior, and PBC remained significantly associated with behavior when intention was added into the model. In conclusion, compared to the previous literature, this study is unique in that it examines indirect PBC measures and also the important role that PBC plays with actual birth control behavior. PMID:25421330

Shift changes, updates, and the on-call architecture in space shuttle mission control.

PubMed

Patterson, E S; Woods, D D

2001-01-01

In domains such as nuclear power, industrial process control, and space shuttle mission control, there is increased interest in reducing personnel during nominal operations. An essential element in maintaining safe operations in high risk environments with this 'on-call' organizational architecture is to understand how to bring called-in practitioners up to speed quickly during escalating situations. Targeted field observations were conducted to investigate what it means to update a supervisory controller on the status of a continuous, anomaly-driven process in a complex, distributed environment. Sixteen shift changes, or handovers, at the NASA Johnson Space Center were observed during the STS-76 Space Shuttle mission. The findings from this observational study highlight the importance of prior knowledge in the updates and demonstrate how missing updates can leave flight controllers vulnerable to being unprepared. Implications for mitigating risk in the transition to 'on-call' architectures are discussed.

Shift changes, updates, and the on-call architecture in space shuttle mission control

NASA Technical Reports Server (NTRS)

Patterson, E. S.; Woods, D. D.

2001-01-01

In domains such as nuclear power, industrial process control, and space shuttle mission control, there is increased interest in reducing personnel during nominal operations. An essential element in maintaining safe operations in high risk environments with this 'on-call' organizational architecture is to understand how to bring called-in practitioners up to speed quickly during escalating situations. Targeted field observations were conducted to investigate what it means to update a supervisory controller on the status of a continuous, anomaly-driven process in a complex, distributed environment. Sixteen shift changes, or handovers, at the NASA Johnson Space Center were observed during the STS-76 Space Shuttle mission. The findings from this observational study highlight the importance of prior knowledge in the updates and demonstrate how missing updates can leave flight controllers vulnerable to being unprepared. Implications for mitigating risk in the transition to 'on-call' architectures are discussed.

Healthcare outcomes assessed with observational study designs compared with those assessed in randomized trials.

PubMed

Anglemyer, Andrew; Horvath, Hacsi T; Bero, Lisa

2014-04-29

Researchers and organizations often use evidence from randomized controlled trials (RCTs) to determine the efficacy of a treatment or intervention under ideal conditions. Studies of observational designs are often used to measure the effectiveness of an intervention in 'real world' scenarios. Numerous study designs and modifications of existing designs, including both randomized and observational, are used for comparative effectiveness research in an attempt to give an unbiased estimate of whether one treatment is more effective or safer than another for a particular population.A systematic analysis of study design features, risk of bias, parameter interpretation, and effect size for all types of randomized and non-experimental observational studies is needed to identify specific differences in design types and potential biases. This review summarizes the results of methodological reviews that compare the outcomes of observational studies with randomized trials addressing the same question, as well as methodological reviews that compare the outcomes of different types of observational studies. To assess the impact of study design (including RCTs versus observational study designs) on the effect measures estimated.To explore methodological variables that might explain any differences identified.To identify gaps in the existing research comparing study designs. We searched seven electronic databases, from January 1990 to December 2013.Along with MeSH terms and relevant keywords, we used the sensitivity-specificity balanced version of a validated strategy to identify reviews in PubMed, augmented with one term ("review" in article titles) so that it better targeted narrative reviews. No language restrictions were applied. We examined systematic reviews that were designed as methodological reviews to compare quantitative effect size estimates measuring efficacy or effectiveness of interventions tested in trials with those tested in observational studies. Comparisons included RCTs versus observational studies (including retrospective cohorts, prospective cohorts, case-control designs, and cross-sectional designs). Reviews were not eligible if they compared randomized trials with other studies that had used some form of concurrent allocation. In general, outcome measures included relative risks or rate ratios (RR), odds ratios (OR), hazard ratios (HR). Using results from observational studies as the reference group, we examined the published estimates to see whether there was a relative larger or smaller effect in the ratio of odds ratios (ROR).Within each identified review, if an estimate comparing results from observational studies with RCTs was not provided, we pooled the estimates for observational studies and RCTs. Then, we estimated the ratio of ratios (risk ratio or odds ratio) for each identified review using observational studies as the reference category. Across all reviews, we synthesized these ratios to get a pooled ROR comparing results from RCTs with results from observational studies. Our initial search yielded 4406 unique references. Fifteen reviews met our inclusion criteria; 14 of which were included in the quantitative analysis.The included reviews analyzed data from 1583 meta-analyses that covered 228 different medical conditions. The mean number of included studies per paper was 178 (range 19 to 530).Eleven (73%) reviews had low risk of bias for explicit criteria for study selection, nine (60%) were low risk of bias for investigators' agreement for study selection, five (33%) included a complete sample of studies, seven (47%) assessed the risk of bias of their included studies,Seven (47%) reviews controlled for methodological differences between studies,Eight (53%) reviews controlled for heterogeneity among studies, nine (60%) analyzed similar outcome measures, and four (27%) were judged to be at low risk of reporting bias.Our primary quantitative analysis, including 14 reviews, showed that the pooled ROR comparing effects from RCTs with effects from observational studies was 1.08 (95% confidence interval (CI) 0.96 to 1.22). Of 14 reviews included in this analysis, 11 (79%) found no significant difference between observational studies and RCTs. One review suggested observational studies had larger effects of interest, and two reviews suggested observational studies had smaller effects of interest.Similar to the effect across all included reviews, effects from reviews comparing RCTs with cohort studies had a pooled ROR of 1.04 (95% CI 0.89 to 1.21), with substantial heterogeneity (I(2) = 68%). Three reviews compared effects of RCTs and case-control designs (pooled ROR: 1.11 (95% CI 0.91 to 1.35)).No significant difference in point estimates across heterogeneity, pharmacological intervention, or propensity score adjustment subgroups were noted. No reviews had compared RCTs with observational studies that used two of the most common causal inference methods, instrumental variables and marginal structural models. Our results across all reviews (pooled ROR 1.08) are very similar to results reported by similarly conducted reviews. As such, we have reached similar conclusions; on average, there is little evidence for significant effect estimate differences between observational studies and RCTs, regardless of specific observational study design, heterogeneity, or inclusion of studies of pharmacological interventions. Factors other than study design per se need to be considered when exploring reasons for a lack of agreement between results of RCTs and observational studies. Our results underscore that it is important for review authors to consider not only study design, but the level of heterogeneity in meta-analyses of RCTs or observational studies. A better understanding of how these factors influence study effects might yield estimates reflective of true effectiveness.

Promoting Hand Hygiene With a Lighting Prompt.

PubMed

Diegel-Vacek, Lauren; Ryan, Catherine

2016-10-01

The objective of this pilot study was to assess an automatic sink light design intervention as a prompt for clinician hand hygiene (as defined by World Health Organization [WHO]). Healthcare-associated infections (HAIs) are still leading causes of morbidity and mortality and contribute to burdens on our healthcare system. Hand hygiene has been related to reducing the rate of HAIs and positively impacting both patient and hospital outcomes. This pilot study was a prospective, longitudinal observational study of a convenience sample of healthcare clinicians. In one inpatient room, clinicians were exposed to a hand hygiene reminder that consisted of a light turning on over the sink as they entered. A control room (the adjacent inpatient room) did not have the intervention. A total of 88 clinician encounters were monitored during the study. On the first observation day at the initial activation of the signal light system, the percentage of clinicians performing hand hygiene upon entering a room was only 7% in the control room and 23% in the intervention room. During the second observation (Day 14), those percentages were 16% in the control room and 30% in the intervention room. During the third observation (Day 21), those percentages were 23% in the control room and 23% in the intervention room. The healthcare system frequently relies on expensive technology to improve healthcare delivery, but implementation of low-cost, low-technology methods such as this light may be effective in prompting hand hygiene. © The Author(s) 2016.

Principles of antibiotic application in children with lobar pneumonia: Step-up or step-down.

PubMed

Li, Yan; Han, Feng; Yang, Yan; Chu, Jianwei

2017-06-01

In order to provide a scientific basis for rational use of antibiotics, we studied and compared the therapeutic effects of step-down and step-up antibiotic treatment schemes in children with lobar pneumonia. Eighty cases of children with lobar pneumonia were enrolled in this study and were randomly divided into two groups: The observation group and the control group, with 40 cases in each group. In the observation group, there were 23 cases with mild and 17 cases with severe lobar pneumonia, and in the control group, 25 were mild and 15 were severe cases. Patients in the control group were treated with antibiotics using step-up therapy method, while patients in the observation group were treated using step-down antibiotic therapy. Our results showed no significant differences in white blood cell (WBC) reduction rate, the course of antibiotic treatment, disappearance time of pulmonary rales and total efficiency in children with mild lobar pneumonia in the observation group after 72 h of treatment. The level of high-sensitivity C-reactive protein (hs-CRP) and procalcitonin (PCT) in the observation group were significantly lower. After 72 h of treatment of children with severe lobar pneumonia in the observation group, the rate of WBC reduction accelerated significantly. Compared to the patients in the control group, the course of antibiotic treatment and disappearance time of pulmonary rales were shortened significantly, while the total efficiency of treatment was improved considerably in the observation group. Also in the observation group, hs-CRP and PCT levels were significantly lower than that in the control group. In severe cases, step-down therapy showed a better result in relieving the inflammatory reactions. The disappearance time of pulmonary rales and the effective rate of treatment was significantly higher than those of step-up therapy. It was obvious that for children with severe lobar pneumonia, step-down therapy produced better results in relieving the inflammatory reaction.

Unusually High Incidences of Staphylococcus aureus Infection within Studies of Ventilator Associated Pneumonia Prevention Using Topical Antibiotics: Benchmarking the Evidence Base

PubMed Central

2018-01-01

Selective digestive decontamination (SDD, topical antibiotic regimens applied to the respiratory tract) appears effective for preventing ventilator associated pneumonia (VAP) in intensive care unit (ICU) patients. However, potential contextual effects of SDD on Staphylococcus aureus infections in the ICU remain unclear. The S. aureus ventilator associated pneumonia (S. aureus VAP), VAP overall and S. aureus bacteremia incidences within component (control and intervention) groups within 27 SDD studies were benchmarked against 115 observational groups. Component groups from 66 studies of various interventions other than SDD provided additional points of reference. In 27 SDD study control groups, the mean S. aureus VAP incidence is 9.6% (95% CI; 6.9–13.2) versus a benchmark derived from 115 observational groups being 4.8% (95% CI; 4.2–5.6). In nine SDD study control groups the mean S. aureus bacteremia incidence is 3.8% (95% CI; 2.1–5.7) versus a benchmark derived from 10 observational groups being 2.1% (95% CI; 1.1–4.1). The incidences of S. aureus VAP and S. aureus bacteremia within the control groups of SDD studies are each higher than literature derived benchmarks. Paradoxically, within the SDD intervention groups, the incidences of both S. aureus VAP and VAP overall are more similar to the benchmarks. PMID:29300363

Influence of control group therapy on the benefit from dose-dense chemotherapy in early breast cancer: a systemic review and meta-analysis.

PubMed

Goldvaser, Hadar; Majeed, Habeeb; Ribnikar, Domen; Šeruga, Boštjan; Ocaña, Alberto; Cescon, David W; Amir, Eitan

2018-06-01

Results from clinical trials of adjuvant dose-dense chemotherapy in patients with breast cancer are inconsistent. A systematic search of MEDLINE identified studies comparing the efficacy of dose-dense adjuvant chemotherapy to a standard treatment. The primary analysis included studies that used identical regimens in the experimental and control groups, but varied only dose density. A secondary analysis included studies that used either different drugs or doses in the experimental and the control groups. Hazard ratios (HRs) and 95% confidence intervals were computed for disease-free survival (DFS) and overall survival (OS) and pooled in a meta-analysis. Subgroup analyses and meta-regression explored drug schedules utilized in control groups and the influence of clinicopathologic variables on benefit from dose-dense therapy. The primary analysis included 5 studies comprising 9819 patients while the secondary analysis included 6 studies comprising 9679 patients. Dose-dense treatment significantly improved DFS (HR 0.85, p < 0.001) and OS (HR 0.86, p = 0.008) in the primary analysis. Similar results were observed in the secondary analysis. Dose-dense schedule was important primarily in studies utilizing paclitaxel every 3 weeks as the control group (interaction p = 0.04 for DFS interaction p = 0.001 for OS). A significantly greater relative magnitude of benefit was observed in pre-menopausal women and those with nodal involvement, but there was no influence of hormone receptor status on results. Adjuvant dose-dense regimens improve breast cancer outcomes. It remains uncertain whether the observed benefit reflects the impact of dose density or the inferiority of paclitaxel every 3 weeks as a control group.

Brain structural plasticity in survivors of a major earthquake

PubMed Central

Lui, Su; Chen, Long; Yao, Li; Xiao, Yuan; Wu, Qi-Zhu; Zhang, Jun-Ran; Huang, Xiao-Qi; Zhang, Wei; Wang, Yu-Qin; Chen, Hua-Fu; Chan, Raymond C.K.; Sweeney, John A.; Gong, Qi-Yong

2013-01-01

Background Stress responses have been studied extensively in animal models, but effects of major life stress on the human brain remain poorly understood. The aim of this study was to determine whether survivors of a major earthquake, who were presumed to have experienced extreme emotional stress during the disaster, demonstrate differences in brain anatomy relative to individuals who have not experienced such stressors. Methods Healthy survivors living in an area devastated by a major earthquake and matched healthy controls underwent 3-dimentional high-resolution magnetic resonance imaging (MRI). Survivors were scanned 13–25 days after the earthquake; controls had undergone MRI for other studies not long before the earthquake. We used optimized voxel-based morphometry analysis to identify regional differences of grey matter volume between the survivors and controls. Results We included 44 survivors (17 female, mean age 37 [standard deviation (SD) 10.6] yr) and 38 controls (14 female, mean age 35.3 [SD 11.2] yr) in our analysis. Compared with controls, the survivors showed significantly lower grey matter volume in the bilateral insula, hippocampus, left caudate and putamen, and greater grey matter volume in the bilateral orbitofrontal cortex and the parietal lobe (all p < 0.05, corrected for multiple comparison). Limitations Differences in the variance of survivor and control data could impact study findings. Conclusion Acute anatomic alterations could be observed in earthquake survivors in brain regions where functional alterations after stress have been described. Anatomic changes in the present study were observed earlier than previously reported and were seen in prefrontal–limbic, parietal and striatal brain systems. Together with the results of previous functional imaging studies, our observations suggest a complex pattern of human brain response to major life stress affecting brain systems that modulate and respond to heightened affective arousal. PMID:23710694

A randomised controlled trial of clinics in secondary schools for adolescents with asthma.

PubMed Central

Salisbury, Chris; Francis, Caia; Rogers, Chris; Parry, Kate; Thomas, Huw; Chadwick, Stephanie; Turton, Pat

2002-01-01

AIM: To compare a nurse-led clinic in schools versus care in general practice for adolescents with asthma. DESIGN OF STUDY: Randomised controlled trial in four schools; parallel observational study in two schools. SETTING: Six comprehensive schools. METHOD: In the randomised trial, pupils were invited to attend asthma review at a nurse-led clinic either in school, or in general practice. The parallel observational study compared pupils invited to practice care within and outside the randomised trial. Primary outcome measures were attendance for asthma review, symptom control, and quality of life. Secondary outcomes were knowledge, attitudes, inhaler technique, use of steroids, school absence, peak flow rate, preference for future care, health service utilisation, and costs. RESULTS: School clinic pupils were more likely to attend an asthma review than those randomised to practice care (90.8% versus 51.0% overall [P < 0.001, not consistent across schools]). No differences were observed in symptom control (P = 0.42) or quality of life (P = 0.63). Pupils attending school clinics had greater knowledge of asthma (difference = +0.38, 95% CI = 0.19 to 0.56), more positive attitudes (difference = +0.21, 95% CI = 0.05 to 0.36), and better inhaler technique (P < 0.001, not consistent across all schools). No differences were observed in school absence or peak flow rate. A majority (63%) of those who had received care at school preferred this model in future. Median costs of providing care at school and at the practice were 32.10 Pounds and 19.80 Pounds, respectively. No differences were observed between the groups in the observational comparison on any outcome. CONCLUSIONS: The schools asthma clinic increased uptake of asthma reviews. There were improvements in various process measures, but not in clinical outcomes. PMID:12528584

Are Randomized Controlled Trials the (G)old Standard? From Clinical Intelligence to Prescriptive Analytics.

PubMed

Van Poucke, Sven; Thomeer, Michiel; Heath, John; Vukicevic, Milan

2016-07-06

Despite the accelerating pace of scientific discovery, the current clinical research enterprise does not sufficiently address pressing clinical questions. Given the constraints on clinical trials, for a majority of clinical questions, the only relevant data available to aid in decision making are based on observation and experience. Our purpose here is 3-fold. First, we describe the classic context of medical research guided by Poppers' scientific epistemology of "falsificationism." Second, we discuss challenges and shortcomings of randomized controlled trials and present the potential of observational studies based on big data. Third, we cover several obstacles related to the use of observational (retrospective) data in clinical studies. We conclude that randomized controlled trials are not at risk for extinction, but innovations in statistics, machine learning, and big data analytics may generate a completely new ecosystem for exploration and validation.

Are Randomized Controlled Trials the (G)old Standard? From Clinical Intelligence to Prescriptive Analytics

PubMed Central

2016-01-01

Despite the accelerating pace of scientific discovery, the current clinical research enterprise does not sufficiently address pressing clinical questions. Given the constraints on clinical trials, for a majority of clinical questions, the only relevant data available to aid in decision making are based on observation and experience. Our purpose here is 3-fold. First, we describe the classic context of medical research guided by Poppers’ scientific epistemology of “falsificationism.” Second, we discuss challenges and shortcomings of randomized controlled trials and present the potential of observational studies based on big data. Third, we cover several obstacles related to the use of observational (retrospective) data in clinical studies. We conclude that randomized controlled trials are not at risk for extinction, but innovations in statistics, machine learning, and big data analytics may generate a completely new ecosystem for exploration and validation. PMID:27383622

Effectiveness of inactivated quadrivalent influenza vaccine in the 2015/2016 season as assessed in both a test-negative case-control study design and a traditional case-control study design.

PubMed

Kimiya, Takahisa; Shinjoh, Masayoshi; Anzo, Makoto; Takahashi, Hiroki; Sekiguchi, Shinichiro; Sugaya, Norio; Takahashi, Takao

2018-04-21

Both traditional case-control studies (TCCSs) and test-negative case-control studies (TNCCSs) are commonly used to assess influenza vaccine effectiveness (VE). To compensate for the fact that observational studies are susceptible to bias, we combined both methods to assess VE in one geographical area during the 2015/2016 season, when influenza A (H1N1)pdm was dominant. Our TNCCS covered 331 children aged 6 months to 15 years who visited our hospital with fever, including 182 with influenza, and our TCCS covered 812 pediatric outpatients aged 6 months to 15 years, including 214 with influenza. Influenza infection and vaccination history were reviewed, and VE was calculated as (1 - odds ratio) × 100. In the TNCCS, VE against influenza A was 68% (95% CI 47-81) overall, and 70% (48-83) for those given two doses; against influenza B, VE was 37% (- 12-64) overall and 49% (2-74) for two doses. In the TCCS, VE against influenza A was 44% (15-63) overall and 44% (13-64) for two doses, and VE against influenza B was 24% (- 19-52) overall and 41% (3-64) for two doses. Both studies confirmed significant VE against influenza A, significant two-dose VE against influenza B, and better two-dose VE than one-dose VE. What is Known: • Influenza vaccine effectiveness (VE) varies from year to year. • Observational studies are conventionally used for VE assessment. However, they are inherently susceptible to bias and confounding. What is New: • This is the first report of influenza VE assessment using more than one observational study and performed in a specific area during the same season. • VE estimates obtained in our traditional case-control study were lower than those in our test-negative case-control study, but both studies found significant VE against influenza.

Cost-efficiency of knowledge creation: randomized controlled trials vs. observational studies.

PubMed

Struck, Rafael; Baumgarten, Georg; Wittmann, Maria

2014-04-01

This article reviews traditional and current perspectives on randomized, controlled trials (RCTs) and observational studies relative to the economic implications for public healthcare stakeholders. It takes an average of 17 years to bring 14% of original research into clinical practice. Results from high-quality observational studies may complement limited RCTs in primary and secondary literature bases, and enhance the incorporation of sound evidence-based guidelines. Observational findings from comprehensive medical databases may offer valuable clues on the effectiveness and relevance of public healthcare interventions. Major expenditures associated with RCTs relate to recruitment, inappropriate site selection, conduct and reporting. Application of business strategies and economic evaluation tools, in addition to the planning and conduct of RCTs, may enhance clinical trial site performances. Considering the strengths and limitations of each study type, clinical researchers should explore the contextual worthiness of either design in promulgating knowledge. They should focus on quality of conduct and reporting that may allow for the liberation of limited public and private clinical research funding.

Drug disposition and modelling before and after gastric bypass: immediate and controlled-release metoprolol formulations.

PubMed

Gesquiere, Ina; Darwich, Adam S; Van der Schueren, Bart; de Hoon, Jan; Lannoo, Matthias; Matthys, Christophe; Rostami, Amin; Foulon, Veerle; Augustijns, Patrick

2015-11-01

The aim of the present study was to evaluate the disposition of metoprolol after oral administration of an immediate and controlled-release formulation before and after Roux-en-Y gastric bypass (RYGB) surgery in the same individuals and to validate a physiologically based pharmacokinetic (PBPK) model for predicting oral bioavailability following RYGB. A single-dose pharmacokinetic study of metoprolol tartrate 200 mg immediate release and controlled release was performed in 14 volunteers before and 6-8 months after RYGB. The observed data were compared with predicted results from the PBPK modelling and simulation of metoprolol tartrate immediate and controlled-release formulation before and after RYGB. After administration of metoprolol immediate and controlled release, no statistically significant difference in the observed area under the curve (AUC(0-24 h)) was shown, although a tendency towards an increased oral exposure could be observed as the AUC(0-24 h) was 32.4% [95% confidence interval (CI) 1.36, 63.5] and 55.9% (95% CI 5.73, 106) higher following RYGB for the immediate and controlled-release formulation, respectively. This could be explained by surgery-related weight loss and a reduced presystemic biotransformation in the proximal gastrointestinal tract. The PBPK values predicted by modelling and simulation were similar to the observed data, confirming its validity. The disposition of metoprolol from an immediate-release and a controlled-release formulation was not significantly altered after RYGB; there was a tendency to an increase, which was also predicted by PBPK modelling and simulation. © 2015 The British Pharmacological Society.

Drug disposition and modelling before and after gastric bypass: immediate and controlled-release metoprolol formulations

PubMed Central

Gesquiere, Ina; Darwich, Adam S; Van der Schueren, Bart; de Hoon, Jan; Lannoo, Matthias; Matthys, Christophe; Rostami, Amin; Foulon, Veerle; Augustijns, Patrick

2015-01-01

Aims The aim of the present study was to evaluate the disposition of metoprolol after oral administration of an immediate and controlled-release formulation before and after Roux-en-Y gastric bypass (RYGB) surgery in the same individuals and to validate a physiologically based pharmacokinetic (PBPK) model for predicting oral bioavailability following RYGB. Methods A single-dose pharmacokinetic study of metoprolol tartrate 200 mg immediate release and controlled release was performed in 14 volunteers before and 6–8 months after RYGB. The observed data were compared with predicted results from the PBPK modelling and simulation of metoprolol tartrate immediate and controlled-release formulation before and after RYGB. Results After administration of metoprolol immediate and controlled release, no statistically significant difference in the observed area under the curve (AUC0–24 h) was shown, although a tendency towards an increased oral exposure could be observed as the AUC0–24 h was 32.4% [95% confidence interval (CI) 1.36, 63.5] and 55.9% (95% CI 5.73, 106) higher following RYGB for the immediate and controlled-release formulation, respectively. This could be explained by surgery-related weight loss and a reduced presystemic biotransformation in the proximal gastrointestinal tract. The PBPK values predicted by modelling and simulation were similar to the observed data, confirming its validity. Conclusions The disposition of metoprolol from an immediate-release and a controlled-release formulation was not significantly altered after RYGB; there was a tendency to an increase, which was also predicted by PBPK modelling and simulation. PMID:25917170

Dietary patterns are associated with disease risk among participants in the women's health initiative observational study

USDA-ARS?s Scientific Manuscript database

Coronary heart disease (CHD) is the leading cause of death in women. A nested case-control study tested whether dietary patterns predicted CHD events among 1224 participants in the Women’s Health Initiative-Observational Study (WHI-OS) with centrally confirmed CHD, fatal or nonfatal myocardial infar...

Medication safety research by observational study design.

PubMed

Lao, Kim S J; Chui, Celine S L; Man, Kenneth K C; Lau, Wallis C Y; Chan, Esther W; Wong, Ian C K

2016-06-01

Observational studies have been recognised to be essential for investigating the safety profile of medications. Numerous observational studies have been conducted on the platform of large population databases, which provide adequate sample size and follow-up length to detect infrequent and/or delayed clinical outcomes. Cohort and case-control are well-accepted traditional methodologies for hypothesis testing, while within-individual study designs are developing and evolving, addressing previous known methodological limitations to reduce confounding and bias. Respective examples of observational studies of different study designs using medical databases are shown. Methodology characteristics, study assumptions, strengths and weaknesses of each method are discussed in this review.

Meta-analyses including data from observational studies.

PubMed

O'Connor, Annette M; Sargeant, Jan M

2014-02-15

Observational studies represent a wide group of studies where the disease or condition of interest is naturally occurring and the investigator does not control allocation to interventions or exposures. Observational studies are used to test hypotheses about the efficacy of interventions or about exposure-disease relationships, to estimate incidence or prevalence of conditions, and to assess the sensitivity and specificity of diagnostic assays. Experimental-study designs and randomized controlled trials (RCTs) can also contribute to the body of evidence about such questions. Meta-analyses (either with or without systematic reviews) aim to combine information from primary research studies to better describe the entire body of work. The aim of meta-analyses may be to obtain a summary effect size, or to understand factors that affect effect sizes. In this paper, we discuss the role of observational studies in meta-analysis questions and some factors to consider when deciding whether a meta-analysis should include results from such studies. Our suggestion is that one should only include studies that are not at high risk of inherent bias when calculating a summary effect size. Study design however can be a meaningful variable in assessment of outcome heterogeneity. Copyright © 2013 Elsevier B.V. All rights reserved.

Differentiation of African components of ancestry to stratify groups in a case-control study of a Brazilian urban population.

PubMed

Silbiger, Vivian N; Hirata, Mario H; Luchessi, Andre D; Genvigir, Fabiana D V; Cerda, Alvaro; Rodrigues, Alice C; Willrich, Maria A V; Arazi, Simone S; Dorea, Egidio L; Bernik, Marcia M S; Faludi, Andre A; Bertolami, Marcelo C; Santos, Carla; Carracedo, Angel; Salas, Antonio; Freire, Ana; Lareu, Maria Victoria; Phillips, Christopher; Porras-Hurtado, Liliana; Fondevila, Manuel; Hirata, Rosario D C

2012-06-01

Balancing the subject composition of case and control groups to create homogenous ancestries between each group is essential for medical association studies. We explored the applicability of single-tube 34-plex ancestry informative markers (AIM) single nucleotide polymorphisms (SNPs) to estimate the African Component of Ancestry (ACA) to design a future case-control association study of a Brazilian urban sample. One hundred eighty individuals (107 case group; 73 control group) self-described as white, brown-intermediate or black were selected. The proportions of the relative contribution of a variable number of ancestral population components were similar between case and control groups. Moreover, the case and control groups demonstrated similar distributions for ACA <0.25 and >0.50 categories. Notably a high number of outlier values (23 samples) were observed among individuals with ACA <0.25. These individuals presented a high probability of Native American and East Asian ancestral components; however, no individuals originally giving these self-described ancestries were observed in this study. The strategy proposed for the assessment of ancestry and adjustment of case and control groups for an association study is an important step for the proper construction of the study, particularly when subjects are taken from a complex urban population. This can be achieved using a straight forward multiplexed AIM-SNPs assay of highly discriminatory ancestry markers.

The effects of single-session music therapy interventions on the observed and self-reported levels of pain control, physical comfort, and relaxation of hospice patients.

PubMed

Krout, R E

2001-01-01

This article describes the process and results of a three-month music therapy clinical effectiveness study conducted with terminally ill patients. The purpose of this study was to quantify and evaluate the effectiveness of single-session music therapy interventions with hospice patients in three patient problem areas: pain control; physical comfort; and relaxation. Data from a total of 90 sessions conducted with a total of 80 subjects served by Hospice of Palm Beach County, Florida, were included in the study. Music therapy services were provided by five board-certified music therapists and one music therapist eligible for board certification. The subjects in this study were receiving regularly scheduled music therapy services from the hospice organization. The study used both behavioral observation and subject's self-reporting as methods of data reporting and recording. Subjects were observed for, or self-reported, their levels of pain control, physical comfort, and relaxation, both before and after each music therapy session. The subjects were served in the environments where music therapy services would normally be delivered (i.e., home, hospital, nursing home, or inpatient acute-care unit of the hospice organization). Music therapy services included live active and passive music-based experiences. These were designed to build and to establish rapport with patient or family, to facilitate family interaction and patient control, to provide support and comfort, to facilitate relaxation, to enable reminiscence and life review, to provide a frame-work for spiritual exploration and validation, and to encourage the identification and expression of feelings of anticipatory mourning and grief. A total of six hypotheses stated that there would be significant pre- to postsession differences in each of the three variables: pain control, physical comfort, and relaxation, as measured during two different session and data collection scenarios. These scenarios included the independent observation and recording of the three subject variables and the subject's self-report of each variable. Reliability correlation coefficients were calculated for each of the different session and data-collection scenarios to help assess the correlation between primary and reliability observers. Pearson product moment correlations indicated reliability agreement coefficients of r = .85 and r = .90. One-tailed t-tests were performed on the collected data for subject pain control, physical comfort, and relaxation. Results of the t-tests were significant at the p < or = .001 (for observed pain control, physical comfort, and relaxation) and p < or = 005 (for self-reported pain control, physical comfort, and relaxation) levels. These results suggest that single-session music therapy interventions appear to be effective in increasing subject pain control, physical comfort, and relaxation during both data collection scenarios. Based on the results of these tests of the analyzed data, the hypotheses were all accepted. Tables illustrate pre- to post-session changes in levels of all three variables from both session and data-collection scenarios. Copies of the data-collection forms are also included in the Appendix. The discussion section addresses limitations of this study and suggestions for future studies.

Efficacy of Psychosocial Interventions in Inducing and Maintaining Alcohol Abstinence in Patients With Chronic Liver Disease: A Systematic Review.

PubMed

Khan, Anam; Tansel, Aylin; White, Donna L; Kayani, Waleed Tallat; Bano, Shah; Lindsay, Jan; El-Serag, Hashem B; Kanwal, Fasiha

2016-02-01

We conducted a systematic review of efficacy of psychosocial interventions in inducing or maintaining alcohol abstinence in patients with chronic liver disease (CLD) and alcohol use disorder (AUD). We performed structured keyword searches in PubMed, PsychINFO, and MEDLINE for original research articles that were published from January 1983 through November 2014 that evaluated the use of psychosocial interventions to induce or maintain alcohol abstinence in patients with CLD and AUD. We identified 13 eligible studies that comprised 1945 patients; 5 were randomized controlled trials (RCTs). Delivered therapies included motivational enhancement therapy, cognitive behavioral therapy (CBT), motivational interviewing, supportive therapy, and psychoeducation either alone or in combination in the intervention group and general health education or treatment as usual in the control group. All studies of induction of abstinence (4 RCTs and 6 observational studies) reported an increase in abstinence among participants in the intervention and control groups. Only an integrated therapy that combined CBT and motivational enhancement therapy with comprehensive medical care, delivered during a period of 2 years, produced a significant increase in abstinence (74% increase in intervention group vs 48% increase in control group, P = .02), which was reported in 1 RCT. All studies of maintenance of abstinence (1 RCT and 2 observational studies) observed recidivism in the intervention and control groups. Only an integrated therapy that combined medical care with CBT produced a significantly smaller rate of recidivism (32.7% in integrated CBT group vs 75% in control group, P = .03), which was reported from 1 observational study. However, data were not collected for more than 2 years on outcomes of patients with CLD and AUD. In a systematic analysis of studies of interventions to induce or maintain alcohol abstinence in patients with CLD and AUD, integrated combination psychotherapy with CBT, motivational enhancement therapy, and comprehensive medical care increased alcohol abstinence. No psychosocial intervention was successful in maintaining abstinence, but an integrated therapy with CBT and medical care appears to reduce recidivism. Copyright © 2016 AGA Institute. Published by Elsevier Inc. All rights reserved.

Efficacy of Psychosocial Interventions in Inducing and Maintaining Alcohol Abstinence in Patients with Chronic Liver Disease – A Systematic Review

PubMed Central

Khan, Anam; Tansel, Aylin; White, Donna L.; Kayani, Waleed Tallat; Bano, Shah; Lindsay, Jan; El-Serag, Hashem B.; Kanwal, Fasiha

2016-01-01

Background & Aims We conducted a systematic review of efficacy of psychosocial interventions in inducing or maintaining alcohol abstinence in patients with chronic liver disease (CLD) and alcohol use disorder (AUD). Methods We performed structured keyword searches in PubMed, PsychINFO, and MEDLINE for original research articles, published from January 1983 through November 2014, that evaluated the use of psychosocial interventions to induce or maintain alcohol abstinence in patients with CLD and AUD. Results We identified 13 eligible studies, comprising 1945 patients; 5 were randomized controlled trials (RCTs). Delivered therapies included motivational enhancement therapy (MET), cognitive behavioral therapy (CBT), motivational interviewing (MI), supportive therapy and psychoeducation either alone or in combination in the intervention group and general health education or treatment as usual in the control group. All studies of induction of abstinence (4 RCTs and 6 observational studies) reported an increase in abstinence among participants in the intervention and control groups. Only an integrated therapy that combined CBT and MET with comprehensive medical care, delivered over 2 years, produced a significant increase in abstinence (74% increase in intervention group versus 48% increase in control group; P=.02), reported in 1 RCT. All studies of maintenance of abstinence (1 RCT and 2 observational studies) observed recidivism in the intervention and control groups. Only an integrated therapy that combined medical care with CBT produced a significantly smaller rate of recidivism (32.7% in integrated CBT group versus 75% decrease in control group, P=.03), reported from 1 observational study. However, data were not collected for more than 2 y on outcomes of patients with CLD and AUD. Conclusion In a systematic analysis of studies of interventions to induce or maintain alcohol abstinence in patients with CLD and AUD, integrated combination psychotherapy with CBT, motivational enhancement therapy, and comprehensive medical care increased alcohol abstinence. No psychosocial intervention was successful in maintaining abstinence, but an integrated therapy with CBT and medical care appears to reduce recidivism. PMID:26256464

Utilization of Positive and Negative Controls to Examine Comorbid Associations in Observational Database Studies.

PubMed

Desai, Jigar R; Hyde, Craig L; Kabadi, Shaum; St Louis, Matthew; Bonato, Vinicius; Katrina Loomis, A; Galaznik, Aaron; Berger, Marc L

2017-03-01

Opportunities to leverage observational data for precision medicine research are hampered by underlying sources of bias and paucity of methods to handle resulting uncertainty. We outline an approach to account for bias in identifying comorbid associations between 2 rare genetic disorders and type 2 diabetes (T2D) by applying a positive and negative control disease paradigm. Association between 10 common and 2 rare genetic disorders [Hereditary Fructose Intolerance (HFI) and α-1 antitrypsin deficiency] and T2D was compared with the association between T2D and 7 negative control diseases with no established relationship with T2D in 4 observational databases. Negative controls were used to estimate how much bias and variance existed in datasets when no effect should be observed. Unadjusted association for common and rare genetic disorders and T2D was positive and variable in magnitude and distribution in all 4 databases. However, association between negative controls and T2D was 200% greater than expected indicating the magnitude and confidence intervals for comorbid associations are sensitive to systematic bias. A meta-analysis using this method demonstrated a significant association between HFI and T2D but not for α-1 antitrypsin deficiency. For observational studies, when covariate data are limited or ambiguous, positive and negative controls provide a method to account for the broadest level of systematic bias, heterogeneity, and uncertainty. This provides greater confidence in assessing associations between diseases and comorbidities. Using this approach we were able to demonstrate an association between HFI and T2D. Leveraging real-world databases is a promising approach to identify and corroborate potential targets for precision medicine therapies.

The influence of joint hypermobility on functional movement control in an elite netball population: A preliminary cohort study.

PubMed

Soper, Kessie; Simmonds, Jane V; Kaz Kaz, Hanadi; Ninis, Nelly

2015-05-01

To ascertain the prevalence of General Joint Hypermobility (GJH) and Joint Hypermobility Syndrome (JHS) in elite level netballers. To investigate whether GJH influences functional movement control and explore whether symptoms of dysautonomia are reported in this population. Observational within-subject cross-sectional design. Field based study. 27 elite level netballers (14-26 years). GJH and JHS were assessed using the Beighton scale, 5 point questionnaire and the Brighton Criteria. Functional movement control was measured using posturography on a force platform and the Star Excursion Balance Test (SEBT). The prevalence of GJH was 63% (n = 17) (Beighton score ≥4/9) and JHS was 15% (n = 4). Symptoms of dysautonomia were minimally prevalent. A trend was observed in which participants with GJH demonstrated increased postural instability on the functional tests. Following Bonferroni adjustment, this was statistically significant only when comparing posturographic data between the distinctly hypermobile participants and the rest of the group for path area (p = 0.002) and velocity (p = 0.002) on the left side. A high prevalence of GJH was observed. A trend towards impairment of functional movement control was observed in the netballers with GJH. This observation did not reach statistical significance except for posturographic path area and velocity. Copyright © 2014 Elsevier Ltd. All rights reserved.

Sensitivity Analysis for Multivalued Treatment Effects: An Example of a Cross-Country Study of Teacher Participation and Job Satisfaction

ERIC Educational Resources Information Center

Chang, Chi

2015-01-01

It is known that interventions are hard to assign randomly to subjects in social psychological studies, because randomized control is difficult to implement strictly and precisely. Thus, in nonexperimental studies and observational studies, controlling the impact of covariates on the dependent variables and addressing the robustness of the…

Observational studies and the difficult quest for causality: lessons from vaccine effectiveness and impact studies.

PubMed

Lipsitch, Marc; Jha, Ayan; Simonsen, Lone

2016-12-01

Although randomized placebo-controlled trials (RCT) are critical to establish efficacy of vaccines at the time of licensure, important remaining questions about vaccine effectiveness (VE)-used here to include individual-level measures and population-wide impact of vaccine programmes-can only be answered once the vaccine is in use, from observational studies. However, such studies are inherently at risk for bias. Using a causal framework and illustrating with examples, we review newer approaches to detecting and avoiding confounding and selection bias in three major classes of observational study design: cohort, case-control and ecological studies. Studies of influenza VE, especially in seniors, are an excellent demonstration of the challenges of detecting and reducing such bias, and so we use influenza VE as a running example. We take a fresh look at the time-trend studies often dismissed as 'ecological'. Such designs are the only observational study design that can measure the overall effect of a vaccination programme [indirect (herd) as well as direct effects], and are in fact already an important part of the evidence base for several vaccines currently in use. Despite the great strides towards more robust observational study designs, challenges lie ahead for evaluating best practices for achieving robust unbiased results from observational studies. This is critical for evaluation of national and global vaccine programme effectiveness. © The Author 2016; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

Generalizability and decision studies to inform observational and experimental research in classroom settings.

PubMed

Bottema-Beutel, Kristen; Lloyd, Blair; Carter, Erik W; Asmus, Jennifer M

2014-11-01

Attaining reliable estimates of observational measures can be challenging in school and classroom settings, as behavior can be influenced by multiple contextual factors. Generalizability (G) studies can enable researchers to estimate the reliability of observational data, and decision (D) studies can inform how many observation sessions are necessary to achieve a criterion level of reliability. We conducted G and D studies using observational data from a randomized control trial focusing on social and academic participation of students with severe disabilities in inclusive secondary classrooms. Results highlight the importance of anchoring observational decisions to reliability estimates from existing or pilot data sets. We outline steps for conducting G and D studies and address options when reliability estimates are lower than desired.

Observer-Based Non-PDC Control for Networked T-S Fuzzy Systems With an Event-Triggered Communication.

PubMed

Peng, Chen; Ma, Shaodong; Xie, Xiangpeng

2017-02-07

This paper addresses the problem of an event-triggered non-parallel distribution compensation (PDC) control for networked Takagi-Sugeno (T-S) fuzzy systems, under consideration of the limited data transmission bandwidth and the imperfect premise matching membership functions. First, a unified event-triggered T-S fuzzy model is provided, in which: 1) a fuzzy observer with the imperfect premise matching is constructed to estimate the unmeasurable states of the studied system; 2) a fuzzy controller is designed following the same premise as the observer; and 3) an output-based event-triggering transmission scheme is designed to economize the restricted network resources. Different from the traditional PDC method, the synchronous premise between the fuzzy observer and the T-S fuzzy system are no longer needed in this paper. Second, by use of Lyapunov theory, a stability criterion and a stabilization condition are obtained for ensuring asymptotically stable of the studied system. On account of the imperfect premise matching conditions are well considered in the derivation of the above criteria, less conservation can be expected to enhance the design flexibility. Compared with some existing emulation-based methods, the controller gains are no longer required to be known a priori. Finally, the availability of proposed non-PDC design scheme is illustrated by the backing-up control of a truck-trailer system.

Effect of Remote Internet Follow-Up on Postradiotherapy Compliance Among Patients with Esophageal Cancer: A Randomized Controlled Study.

PubMed

Wang, Ping; Yang, Lin; Hua, Zhongsheng

2015-11-01

To explore the effects of using remote Internet follow-up on postradiotherapy compliance with medical advice provided to patients with esophageal cancer. Between January 1 and August 1, 2013, in total, 128 patients with esophageal squamous cell cancer treated with radiotherapy were randomly assigned to either an observation group (n=64) or a control group (n=64). The control group received routine outpatient follow-up, whereas the observation group received additional remote Internet follow-up for 6 months after discharge from the hospital. The treatment effects and compliance were investigated using a questionnaire. At 3 months and 6 months after discharge, patients in the observation group had sought significantly more consultations and undergone more periodic re-examinations than patients in the control group (all p<0.001). Furthermore, both the disease-free survival rate and the symptom reduction rate were significantly higher in the observation group compared with the control group (all p<0.001). Remote Internet follow-up is an easy and fast method for improving postradiotherapy compliance with medical instructions and promoting normalization among patients with esophageal cancer.

Efficacy of sublingual specific immunotherapy in intermittent and persistent allergic rhinitis in children: an observational case-control study on 171 patients. The EFESO-children multicenter trial.

PubMed

Acquistapace, Franca; Agostinis, Fabio; Castella, Vincenzo; Kantar, Ahmad; Novembre, Elio; Perrone, Maria Rosaria; Pietrasanta, Michele; Sambugaro, Renato; Milani, Massimo

2009-11-01

Sublingual-specific immunotherapy (SLIT) is considered as a valid treatment of respiratory allergies. However, there are few data on large sample size regarding its clinical role in 'real life' in term of reduction of symptoms, rescue medications and prevention of asthma in patients suffering from allergic rhinitis (AR) especially in children. We performed a multicenter, case-control study to evaluate the effect of SLIT in children (age 6-18 yr) with intermittent or persistent AR. 171 children (27% girls and 73% boys) with AR due to seasonal or perennial allergens were enrolled in a multicenter case-control study. Cases (n = 90) were defined as patients with intermittent (64%) or persistent (36%) AR who were treated for at least two consecutive years with specific SLIT with the related allergen extracts (SLITone ALK-Abellò). Controls (n = 81) were defined as sex-age- and type of allergen matched AR children who were never treated with specific immunotherapy and had no asthmatic symptoms at the beginning of observation period. Main outcomes of the study were the rhinoconjunctivitis symptom score (SS) (sneezing, rhinorrea, nasal itch, congestion, ocular itch and watery eyes) with a ranging scale from 0 (=no symptoms) to 3 (=severe symptoms) and the medication score (MS) evaluating symptomatic drug intake (antihystamine and inhaled corticosteroids). SS and MS were evaluated at the end of the observational period in relation with the period, considering the last 12 months, in which patients suffered the highest symptoms levels (i.e., peak of relevant pollen season (seasonal AR) or during the period of maximum allergen exposure in case of perennial AR). Secondary outcome of the study was the development of asthma symptoms during the observation period. SS (mean +/- SD) was 4.5 +/- 2.5 in cases and 9.0 +/- 3.0 in controls (-50%) (p = 0.0001). MS (mean +/- SD) was 2.5 +/- 1.9 and 3.6 +/- 2.1 in the case and control groups, respectively (-31%) (p = 0.0001). At the end of the observation period asthma symptoms were present in 14 subjects in the case group (15%) and in 20 children (24%) in the control group (p = 0.13). New skin sensitizations appeared in 6% of cases (n = 2) and in 36% (n = 12) of the controls (p = 0.001). The EFESO trial shows that a 2-yr once daily SLIT treatment in children with intermittent or persistent AR is associated with lower symptom and medication scores in comparison with subjects treated with symptomatic drugs only.

Incorporating a disturbance observer with direct velocity feedback for control of human-induced vibrations

NASA Astrophysics Data System (ADS)

Nyawako, Donald; Reynolds, Paul; Hudson, Emma

2016-04-01

Feedback control strategies are desirable for disturbance rejection of human-induced vibrations in civil engineering structures as human walking forces cannot easily be measured. In relation to human-induced vibration control studies, most past researches have focused on floors and footbridges and the widely used linear controller implemented in the trials has been the direct velocity feedback (DVF) scheme. With appropriate compensation to enhance its robustness, it has been shown to be effective at damping out the problematic modes of vibration of the structures in which the active vibration control systems have been implemented. The work presented here introduces a disturbance observer (DOB) that is used with an outer-loop DVF controller. Results of analytical studies presented in this work based on the dynamic properties of a walkway bridge structure demonstrate the potential of this approach for enhancing the vibration mitigation performance offered by a purely DVF controller. For example, estimates of controlled frequency response functions indicate improved attenuation of vibration around the dominant frequency of the walkway bridge structure as well as at higher resonant frequencies. Controlled responses from three synthesized walking excitation forces on a walkway bridge structure model show that the inclusion of the disturbance observer with an outer loop DVF has potential to improve on the vibration mitigation performance by about 3.5% at resonance and 6-10% off-resonance. These are realised with hard constraints being imposed on the low frequency actuator displacements.

Stabilising falling liquid film flows using feedback control

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

Thompson, Alice B., E-mail: alice.thompson1@imperial.ac.uk; Gomes, Susana N.; Pavliotis, Grigorios A.

2016-01-15

Falling liquid films become unstable due to inertial effects when the fluid layer is sufficiently thick or the slope sufficiently steep. This free surface flow of a single fluid layer has industrial applications including coating and heat transfer, which benefit from smooth and wavy interfaces, respectively. Here, we discuss how the dynamics of the system are altered by feedback controls based on observations of the interface height, and supplied to the system via the perpendicular injection and suction of fluid through the wall. In this study, we model the system using both Benney and weighted-residual models that account for themore » fluid injection through the wall. We find that feedback using injection and suction is a remarkably effective control mechanism: the controls can be used to drive the system towards arbitrary steady states and travelling waves, and the qualitative effects are independent of the details of the flow modelling. Furthermore, we show that the system can still be successfully controlled when the feedback is applied via a set of localised actuators and only a small number of system observations are available, and that this is possible using both static (where the controls are based on only the most recent set of observations) and dynamic (where the controls are based on an approximation of the system which evolves over time) control schemes. This study thus provides a solid theoretical foundation for future experimental realisations of the active feedback control of falling liquid films.« less

Strategies to Make Ramadan Fasting Safer in Type 2 Diabetics: A Systematic Review and Network Meta-analysis of Randomized Controlled Trials and Observational Studies.

PubMed

Lee, Shaun Wen Huey; Lee, Jun Yang; Tan, Christina San San; Wong, Chee Piau

2016-01-01

Ramadan is the holy month for Muslims whereby they fast from predawn to after sunset and is observed by all healthy Muslim adults as well as a large population of type 2 diabetic Muslims.To determine the comparative effectiveness of various strategies that have been used for type 2 diabetic Muslim who fast during Ramadan.A systematic review and network meta-analysis of randomized controlled studies (RCT) as well as observational studies for patients with type 2 diabetes who fasted during Ramadan was conducted. Eight databases were searched from January 1980 through October 2015 for relevant studies. Two reviewers independently screened and assessed study for eligibility, assessed the risk of bias, and extracted relevant data. A network meta-analysis for each outcome was fitted separately, combining direct and indirect evidence for each comparison.Twenty-nine studies, 16 RCTs and 13 observational studies each met the inclusion criteria. The most common strategy used was drug changes during the Ramadan period, which found that the use of DPP-4 (Dipeptidyl peptidase inhibitor -4) inhibitors were associated with a reduction in incidence of experiencing hypoglycemia during Ramadan in both RCTs (pooled relative risk: 0.56; 95% confidence interval: 0.44-0.72) as well as in observational studies (pooled relative risk: 0.27; 0.09-0.75). Ramadan-focused education was shown to be beneficial in reducing hypoglycemia in observational studies but not RCTs (0.25 versus 1.00). Network meta-analyses suggest that incretin mimetics can reduce the risk of hypoglycemia by nearly 1.5 times.The newer antidiabetic agents appear to lower the risk of hypoglycemia and improved glycemic control when compared with sulfonylureas. Ramadan-focused education shows to be a promising strategy but more rigorous examination from RCTs are required.

Imitation and Emulation by Dogs Using a Bidirectional Control Procedure

PubMed Central

Miller, Holly C.; Rayburn-Reeves, Rebecca; Zentall, Thomas R.

2009-01-01

A successful procedure for studying imitative behavior in non-humans is the bidirectional control procedure in which observers are exposed to a demonstrator that responds by moving a manipulandum in one of two different directions (e.g., left vs. right). Imitative learning is demonstrated when observers make the response in the direction that they observed it being made. This procedure controls for socially mediated effects (the mere presence of a demonstrator), stimulus enhancement (attention drawn to a manipulandum by its movement), and if an appropriate control is included, emulation (learning how the environment works). Recent research with dogs has found that dogs may not demonstrate imitative learning when the demonstrator is human. In the present research, we found that when odors were controlled for, dogs imitated the direction of a screen push demonstrated by another dog more than in a control condition in which they observed the screen move independently while another dog was present. Furthermore, we found that dogs would match the direction of screen push demonstrated by a human and they were equally likely to match the direction in which the screen moved independently while a human was present. PMID:18977419

A case-control study: occupational cooking and the risk of uveal melanoma

PubMed Central

2010-01-01

Background A European-wide population based case-control study (European rare cancer study) undertaken in nine European countries examined risk factors for uveal melanoma. They found a positive association between cooks and the risk of uveal melanoma. In our study we examine whether cooks or people who worked in cook related jobs have an increased uveal melanoma risk. Methods We conducted a case-control study during 2002 and 2005. Overall, 1653 eligible subjects (age range: 20-74 years, living in Germany) participated. Interviews were conducted with 459 incident uveal melanoma cases, 827 population controls, 180 ophthalmologist controls and 187 sibling controls. Data on occupational exposure were obtained from a self-administered postal questionnaire and a computer-assisted telephone interview. We used conditional logistic regression to estimate odds ratios adjusting for the matching factors. Results Overall, we did not observe an increased risk of uveal melanoma among people who worked as cooks or who worked in cook related jobs. When we restricted the source population of our study to the population of the Federal State of Northrhine-Westphalia, we observed an increased risk among subjects who were categorized as cooks in the cases-control analysis. Conclusion Our results are in conflict with former results of the European rare cancer study. Considering the rarity of the disease laboratory in vitro studies of human uveal melanoma cell lines should be done to analyze potential exposure risk factors like radiation from microwaves, strong light from incandescent ovens, or infrared radiation. PMID:20969762

Applying Statistical Process Quality Control Methodology to Educational Settings.

ERIC Educational Resources Information Center

Blumberg, Carol Joyce

A subset of Statistical Process Control (SPC) methodology known as Control Charting is introduced. SPC methodology is a collection of graphical and inferential statistics techniques used to study the progress of phenomena over time. The types of control charts covered are the null X (mean), R (Range), X (individual observations), MR (moving…

Reactive and Proactive Interference Control in Adults with Autism Spectrum Disorder across the Lifespan

ERIC Educational Resources Information Center

Lever, Anne G.; Ridderinkhof, K. Richard; Marsman, Maarten; Geurts, Hilde M.

2017-01-01

As a large heterogeneity is observed across studies on interference control in autism spectrum disorder (ASD), research may benefit from the use of a cognitive framework that models specific processes underlying reactive and proactive control of interference. Reactive control refers to the expression and suppression of responses and proactive…

[Factors affecting the control of blood pressure and lipid levels in patients with cardiovascular disease: the PREseAP Study].

PubMed

Orozco-Beltrán, Domingo; Brotons, Carlos; Moral, Irene; Soriano, Nuria; Del Valle, María A; Rodríguez, Ana I; Pepió, Josep M; Pastor, Ana

2008-03-01

The aim of this observational study was to identify factors influencing the control of blood pressure (i.e., <140/90 mmHg, or <130/80 mmHg in diabetic patients) and low-density lipoprotein (LDL) cholesterol level (<100 mg/dL) in 1223 patients with cardiovascular disease. Overall, 70.2% of patients were men, and their mean age was 66.4 years. Blood pressure was poorly controlled in 50.9% (95% confidence interval [CI], 46.9%-54.8%) and the LDL cholesterol level was poorly controlled in 60.1% (95% CI, 56.3%-63.9%). Determinants of poor blood pressure control were diabetes, hypertension, no previous diagnosis of heart failure, previous diagnosis of peripheral artery disease or stroke, obesity, and no lipid-lowering treatment. Determinants of poor LDL cholesterol control were no lipid-lowering treatment, no previous diagnosis of ischemic heart disease, no antihypertensive treatment, and dyslipidemia. The factors affecting blood pressure control were different from those affecting LDL cholesterol control, an observation that should be taken into account when implementing treatment recommendations for achieving therapeutic objectives in secondary prevention.

Early vasopressor use following traumatic injury: a systematic review.

PubMed

Hylands, Mathieu; Toma, Augustin; Beaudoin, Nicolas; Frenette, Anne Julie; D'Aragon, Frédérick; Belley-Côté, Émilie; Charbonney, Emmanuel; Møller, Morten Hylander; Laake, Jon Henrik; Vandvik, Per Olav; Siemieniuk, Reed Alexander; Rochwerg, Bram; Lauzier, François; Green, Robert S; Ball, Ian; Scales, Damon; Murthy, Srinivas; Kwong, Joey S W; Guyatt, Gordon; Rizoli, Sandro; Asfar, Pierre; Lamontagne, François

2017-11-17

Current guidelines suggest limiting the use of vasopressors following traumatic injury; however, wide variations in practice exist. Although excessive vasoconstriction may be harmful, these agents may help reduce administration of potentially harmful resuscitation fluids. This systematic review aims to compare early vasopressor use to standard resuscitation in adults with trauma-induced shock. Systematic review. We searched MEDLINE, EMBASE, ClinicalTrials.gov and the Central Register of Controlled Trials from inception until October 2016, as well as the proceedings of 10 relevant international conferences from 2005 to 2016. Randomised controlled trials and controlled observational studies that compared the early vasopressor use with standard resuscitation in adults with acute traumatic injury. Of 8001 citations, we retrieved 18 full-text articles and included 6 studies (1 randomised controlled trial and 5 observational studies), including 2 published exclusively in abstract form. Across observational studies, vasopressor use was associated with increased short-term mortality, with unadjusted risk ratios ranging from 2.31 to 7.39. However, the risk of bias was considered high in these observational studies because patients who received vasopressors were systematically sicker than patients treated without vasopressors. One clinical trial (n=78) was too imprecise to yield meaningful results. Two clinical trials are currently ongoing. No study measured long-term quality of life or cognitive function. Existing data on the effects of vasopressors following traumatic injury are of very low quality according to the Grading of Recommendations, Assessment, Development and Evaluation methodology. With emerging evidence of harm associated with aggressive fluid resuscitation and, in selected subgroups of patients, with permissive hypotension, the alternatives to vasopressor therapy are limited. Observational data showing that vasopressors are part of usual care would provide a strong justification for high-quality clinical trials of early vasopressor use during trauma resuscitation. CRD42016033437. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

"In God we trust" and other factors influencing trial of labor versus Repeat cesarean section.

PubMed

Pomeranz, Meir; Arbib, Nissim; Haddif, Limor; Reissner, Hana; Romem, Yitzhak; Biron, Tal

2018-07-01

To investigate factors influencing women's decisions to undergo trial of labor after cesarean (TOLAC) or elective repeat cesarean delivery (ERCD) based on the Multidimensional Health Locus of Control (MHLC), religious observance and family planning. Cross-sectional study of candidates for TOLAC or ERCD at two hospitals in Israel. Eligible women completed a demographic questionnaire and Form C of the MHLC scale. The study included 197 women. Those who chose TOLAC (N = 101) were more religiously observant, wanted more children and had higher Internal and Chance health locus of control. Women who chose ERCD (N = 96) were more likely to be secular and had a higher health locus of control influenced by Powerful Others, notably physicians. Women not influenced by others were more likely to choose TOLAC. A woman's choice of TOLAC or ERCD is influenced by her sense of control over her health, degree of religious observance and number of children desired. Healthcare providers can use this information to better understand, counsel and educate women regarding appropriate delivery decisions. Women who feel in control of their health, educated about delivery options and are less influenced by provider preference, might choose TOLAC; thus, reducing the rate of unnecessary ERCD.

Does Observation of Postural Imbalance Induce a Postural Reaction?

PubMed Central

Tia, Banty; Saimpont, Arnaud; Paizis, Christos; Mourey, France; Fadiga, Luciano; Pozzo, Thierry

2011-01-01

Background Several studies bring evidence that action observation elicits contagious responses during social interactions. However automatic imitative tendencies are generally inhibited and it remains unclear in which conditions mere action observation triggers motor behaviours. In this study, we addressed the question of contagious postural responses when observing human imbalance. Methodology/Principal Findings We recorded participants' body sway while they observed a fixation cross (control condition), an upright point-light display of a gymnast balancing on a rope, and the same point-light display presented upside down. Our results showed that, when the upright stimulus was displayed prior to the inverted one, centre of pressure area and antero-posterior path length were significantly greater in the upright condition compared to the control and upside down conditions. Conclusions/Significance These results demonstrate a contagious postural reaction suggesting a partial inefficiency of inhibitory processes. Further, kinematic information was sufficient to trigger this reaction. The difference recorded between the upright and upside down conditions indicates that the contagion effect was dependent on the integration of gravity constraints by body kinematics. Interestingly, the postural response was sensitive to habituation, and seemed to disappear when the observer was previously shown an inverted display. The motor contagion recorded here is consistent with previous work showing vegetative output during observation of an effortful movement and could indicate that lower level control facilitates contagion effects. PMID:21423622

Control of oral malodour by dentifrices measured by gas chromatography.

PubMed

Newby, Evelyn E; Hickling, Jenneth M; Hughes, Francis J; Proskin, Howard M; Bosma, Marylynn P

2008-04-01

To evaluate the effect of toothpaste treatments on levels of oral volatile sulphur compounds (VSCs) measured by gas chromatography in two clinical studies. These were blinded, randomised, controlled, crossover studies with 16 (study A) or 20 (study B) healthy volunteers between the ages of 19-54. Study A: breath samples were collected at baseline, immediately and lhr after brushing. Four dentifrices (Zinc A, Zinc B, commercially available triclosan dentifrice and zinc free control) were evaluated. Study B: breath samples were collected at baseline, immediately, 1, 2, 3 and 7 hours after treatment. Subjects consumed a light breakfast then provided an additional breath sample between baseline assessment and treatment. Two dentifrices (gel-to-foam and a commercially available triclosan dentrifrice) were evaluated. Breath samples were collected in syringes and analysed for VSCs (hydrogen sulphide, methyl mercaptan and Total VSCs) utilising gas chromatography (GC) with flame photometric detection. Study A: immediately after treatment, a statistically significant reduction in VSCs from baseline was observed for Zinc A product only. A statistically significant reduction in VSCs from baseline was observed after 1 hour for all products. Both zinc products exhibited a significantly greater reduction from baseline VSCs than Colgate Total and Control at all time points. Study B: a statistically significant reduction in VSCs from baseline was observed at all time points for both products. The gel-to-foam product exhibited significantly greater reduction from baseline Total VSC concentration than Colgate Total at all time points from 1 hour post-treatment. Control of oral malodour by toothpaste treatment, evaluated as VSC levels using GC, has been demonstrated. Zinc is effective at reducing VSCs and the efficacy of zinc is formulation dependent. A gel-to-foam dentifrice was more effective at reducing VSCs than Colgate Total up to 7 hours.

The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Statement: guidelines for reporting observational studies.

PubMed

von Elm, Erik; Altman, Douglas G; Egger, Matthias; Pocock, Stuart J; Gøtzsche, Peter C; Vandenbroucke, Jan P

2014-12-01

Much biomedical research is observational. The reporting of such research is often inadequate, which hampers the assessment of its strengths and weaknesses and of a study's generalisability. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Initiative developed recommendations on what should be included in an accurate and complete report of an observational study. We defined the scope of the recommendations to cover three main study designs: cohort, case-control, and cross-sectional studies. We convened a 2-day workshop in September 2004, with methodologists, researchers, and journal editors to draft a checklist of items. This list was subsequently revised during several meetings of the coordinating group and in e-mail discussions with the larger group of STROBE contributors, taking into account empirical evidence and methodological considerations. The workshop and the subsequent iterative process of consultation and revision resulted in a checklist of 22 items (the STROBE Statement) that relate to the title, abstract, introduction, methods, results, and discussion sections of articles. 18 items are common to all three study designs and four are specific for cohort, case-control, or cross-sectional studies. A detailed Explanation and Elaboration document is published separately and is freely available on the Web sites of PLoS Medicine, Annals of Internal Medicine, and Epidemiology. We hope that the STROBE Statement will contribute to improving the quality of reporting of observational studies. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Mobile phone use and risk of tumors: a meta-analysis.

PubMed

Myung, Seung-Kwon; Ju, Woong; McDonnell, Diana D; Lee, Yeon Ji; Kazinets, Gene; Cheng, Chih-Tao; Moskowitz, Joel M

2009-11-20

Case-control studies have reported inconsistent findings regarding the association between mobile phone use and tumor risk. We investigated these associations using a meta-analysis. We searched MEDLINE (PubMed), EMBASE, and the Cochrane Library in August 2008. Two evaluators independently reviewed and selected articles based on predetermined selection criteria. Of 465 articles meeting our initial criteria, 23 case-control studies, which involved 37,916 participants (12,344 patient cases and 25,572 controls), were included in the final analyses. Compared with never or rarely having used a mobile phone, the odds ratio for overall use was 0.98 for malignant and benign tumors (95% CI, 0.89 to 1.07) in a random-effects meta-analysis of all 23 studies. However, a significant positive association (harmful effect) was observed in a random-effects meta-analysis of eight studies using blinding, whereas a significant negative association (protective effect) was observed in a fixed-effects meta-analysis of 15 studies not using blinding. Mobile phone use of 10 years or longer was associated with a risk of tumors in 13 studies reporting this association (odds ratio = 1.18; 95% CI, 1.04 to 1.34). Further, these findings were also observed in the subgroup analyses by methodologic quality of study. Blinding and methodologic quality of study were strongly associated with the research group. The current study found that there is possible evidence linking mobile phone use to an increased risk of tumors from a meta-analysis of low-biased case-control studies. Prospective cohort studies providing a higher level of evidence are needed.

Clinical comparison of Zero-profile interbody fusion device and anterior cervical plate interbody fusion in treating cervical spondylosis.

PubMed

Yan, Bin; Nie, Lin

2015-01-01

the aim of the study was to compare the clinical effect of Zero-profile interbody fusion device (Zero-P) with anterior cervical plate interbody fusion system (PCB) in treating cervical spondylosis. a total of 98 patients with cervical spondylosis (110 segments) in February 2011 to January 2013 were included in our hospital. All participants were randomly divided into observation group and control group with 49 cases in each group. The observation group was treated with Zero-P, while the control group received PCB treatment. Comparison of the two groups in neurological function score (JOA), pain visual analogue scale (VAS), the neck disability index (NDI), quality of life score (SF-36) and cervical curvature (Cobb angle) change were recorded and analyzed before and after treatment. The observation group was found with 90% excellent and good rate, which was higher than that of the control group (80%). Dysphagia rate in observational group was 16.33% (8/49), which was significantly less than that in control group (46.94%). Operation time and bleeding volume in the observation group was less than those in control group. Postoperative improvements of JOA score, VAS score, and NDI in observational group were also significantly better than that in control group (P<0.05). The clinical effect of Zero-P and PCB for the treatment of cervical spondylosis was quite fair, but Zero-P showed a better therapeutic effect with improvement of life quality.

Comparison of impact on seizure frequency and epileptiform discharges of children with epilepsy from topiramate and phenobarbital.

PubMed

Wang, Y-Y; Wang, M-G; Yao, D; Huang, X-X; Zhang, T; Deng, X-Q

2016-03-01

To study the impact on seizure frequency and epileptiform discharges of children with epilepsy from topiramate (TPM) and phenobarbital (PB). Two hundred cases children with epilepsy from August 2010 to August 2013 in our hospital were sampled and randomly divided into two groups. The observation group was treated with TPM while the control group with PB, and then comparing seizure frequency, efficiency, and adverse reactions of two groups. The reduced number of partial seizures, generalized seizures, and total seizures in the observation group were significantly higher than those in the control group, and the rate of cure, markedly effective and total efficiency in observation group were significantly higher than those in the control group. However, the adverse reactions in observation group were significantly lower than those in the control group. Thus, differences were statistically significant (p<0.05). Compared with PB, TPM showed a better effect on epilepsy treatment with less adverse reactions which were worthy of clinical recommendation.

Robust output feedback stabilization for a flexible marine riser system.

PubMed

Zhao, Zhijia; Liu, Yu; Guo, Fang

2017-12-06

The aim of this paper is to develop a boundary control for the vibration reduction of a flexible marine riser system in the presence of parametric uncertainties and system states obtained inaccurately. To this end, an adaptive output feedback boundary control is proposed to suppress the riser's vibration fusing with observer-based backstepping, high-gain observers and robust adaptive control theory. In addition, the parameter adaptive laws are designed to compensate for the system parametric uncertainties, and the disturbance observer is introduced to mitigate the effects of external environmental disturbance. The uniformly bounded stability of the closed-loop system is achieved through rigorous Lyapunov analysis without any discretisation or simplification of the dynamics in the time and space, and the state observer error is ensured to exponentially converge to zero as time grows to infinity. In the end, the simulation and comparison studies are carried out to illustrate the performance of the proposed control under the proper choice of the design parameters. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

Efficacy of Multivitamin/mineral Supplementation to Reduce Chronic Disease Risk: A Critical Review of the Evidence from Observational Studies and Randomized Controlled Trials.

PubMed

Angelo, Giana; Drake, Victoria J; Frei, Balz

2015-01-01

We reviewed recent scientific evidence regarding the effects of multivitamin/mineral (MVM) supplements on risk of chronic diseases, including cancer, cardiovascular disease, and age-related eye diseases. Data from randomized controlled trials (RCTs) and observational, prospective cohort studies were examined. The majority of scientific studies investigating the use of MVM supplements in chronic disease risk reduction reported no significant effect. However, the largest and longest RCT of MVM supplements conducted to date, the Physicians' Health Study II (PHS II), found a modest and significant reduction in total and epithelial cancer incidence in male physicians, consistent with the Supplémentation en Vitamines et Minéraux Antioxydants (SU.VI.MAX) trial. In addition, PHS II found a modest and significant reduction in the incidence of nuclear cataract, in agreement with several other RCTs and observational, prospective cohort studies. The effects of MVM use on other subtypes of cataract and age-related macular degeneration remain unclear. Neither RCTs nor prospective cohort studies are without their limitations. The placebo-controlled trial design of RCTs may be inadequate for nutrient interventions, and residual confounding, measurement error, and the possibility of reverse causality are inherent to any observational study. National surveys show that micronutrient inadequacies are widespread in the US and that dietary supplements, of which MVMs are the most common type, help fulfill micronutrient requirements in adults and children.

Reactive and proactive interference control in adults with autism spectrum disorder across the lifespan.

PubMed

Lever, Anne G; Ridderinkhof, K Richard; Marsman, Maarten; Geurts, Hilde M

2017-02-01

As a large heterogeneity is observed across studies on interference control in autism spectrum disorder (ASD), research may benefit from the use of a cognitive framework that models specific processes underlying reactive and proactive control of interference. Reactive control refers to the expression and suppression of responses and proactive control refers to the adjustment of response to previous situations. We administered a Simon conflict task in 2 independent adult samples (IQ >80) and applied distributional analyses to examine temporal dynamics of interference control in ASD. Along comparable interference effects in both reactive and proactive control, young men (n = 23, 18-36 years) diagnosed with ASD made as many fast errors on conflict trials as neurotypical controls (n = 19) and showed similar suppression on slow responses (Study 1). However, over the adult life span (19-79 years), individuals with ASD (n = 118) made fewer fast errors on conflict trials, and had overall slower and more accurate responses than controls (n = 160; Study 2). These results converge to the idea that individuals with ASD adopt a more cautious response bias over the adult life span, which is not yet observed among young adults. Our findings suggest that it is fruitful to distinguish different processes involved in interference control and contribute to an increased understanding of interference control mechanisms in adults with ASD. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Diagnostic value of T-Spot TB combined with INF-γ and IL-27 in tuberculous pleurisy

PubMed Central

Zhang, Meng; Xiong, Dedong; Li, Hongxia; Wang, Zonglan; Li, Renzhe

2018-01-01

The purpose of the present study was to investigate the diagnostic value of T cells spot test (T-Spot TB) combined with interferon-γ (INF-γ) and interleukin-27 (IL-27) in tuberculous pleurisy. Sixty patients with tuberculous pleurisy (observation group) and 60 patients with non-tuberculous pleurisy (control group) were enrolled in this study. T-Spot TB was performed to detect the pleural effusion of two groups of patients. Levels of IFN-γ and IL-27 in serum and pleural effusion were detected by enzyme-linked immunosorbent assay (ELISA). Relative expression of IFN-γ mRNA and IL-27 mRNA in peripheral blood mononuclear cells were detected by RT-PCR. Positive rate of T-Spot TB in observation group was 96.7% (58 cases), which was significantly higher than that in control group (p<0.05). Concentration of INF-γ in pleural effusion of observation group was 468.6±24.8 ng/l, which was significantly higher than that in control group (131.3±18.7 ng/l, p<0.05). Concentration of IL-27 in pleural effusion of observation group was 423.4±37.2 ng/l, which was significantly higher than that in control group (116.2±15.5 ng/l, p<0.05). Concentrations of INF-γ and IL-27 in serum of observation group were 48.2±13.4 and 41.7±10.6 ng/l, respectively, which were significantly higher than those in control group (38.6±11.2 and 35.3±8.4 ng/l, p<0.05). Relative expression levels of INF-γ mRNA and IL-27 mRNA in observation group were significantly higher than those in control group (p<0.05). Therefore, combination of T-Spot TB with INF-γ and IL-27 has significant application value in the clinical diagnosis of tuberculous pleurisy, and should be popularized. PMID:29399137

Diagnostic value of T-Spot TB combined with INF-γ and IL-27 in tuberculous pleurisy.

PubMed

Zhang, Meng; Xiong, Dedong; Li, Hongxia; Wang, Zonglan; Li, Renzhe

2018-02-01

The purpose of the present study was to investigate the diagnostic value of T cells spot test (T-Spot TB) combined with interferon-γ (INF-γ) and interleukin-27 (IL-27) in tuberculous pleurisy. Sixty patients with tuberculous pleurisy (observation group) and 60 patients with non-tuberculous pleurisy (control group) were enrolled in this study. T-Spot TB was performed to detect the pleural effusion of two groups of patients. Levels of IFN-γ and IL-27 in serum and pleural effusion were detected by enzyme-linked immunosorbent assay (ELISA). Relative expression of IFN-γ mRNA and IL-27 mRNA in peripheral blood mononuclear cells were detected by RT-PCR. Positive rate of T-Spot TB in observation group was 96.7% (58 cases), which was significantly higher than that in control group (p<0.05). Concentration of INF-γ in pleural effusion of observation group was 468.6±24.8 ng/l, which was significantly higher than that in control group (131.3±18.7 ng/l, p<0.05). Concentration of IL-27 in pleural effusion of observation group was 423.4±37.2 ng/l, which was significantly higher than that in control group (116.2±15.5 ng/l, p<0.05). Concentrations of INF-γ and IL-27 in serum of observation group were 48.2±13.4 and 41.7±10.6 ng/l, respectively, which were significantly higher than those in control group (38.6±11.2 and 35.3±8.4 ng/l, p<0.05). Relative expression levels of INF-γ mRNA and IL-27 mRNA in observation group were significantly higher than those in control group (p<0.05). Therefore, combination of T-Spot TB with INF-γ and IL-27 has significant application value in the clinical diagnosis of tuberculous pleurisy, and should be popularized.

Cooperative Robots to Observe Moving Targets: Review.

PubMed

Khan, Asif; Rinner, Bernhard; Cavallaro, Andrea

2018-01-01

The deployment of multiple robots for achieving a common goal helps to improve the performance, efficiency, and/or robustness in a variety of tasks. In particular, the observation of moving targets is an important multirobot application that still exhibits numerous open challenges, including the effective coordination of the robots. This paper reviews control techniques for cooperative mobile robots monitoring multiple targets. The simultaneous movement of robots and targets makes this problem particularly interesting, and our review systematically addresses this cooperative multirobot problem for the first time. We classify and critically discuss the control techniques: cooperative multirobot observation of multiple moving targets, cooperative search, acquisition, and track, cooperative tracking, and multirobot pursuit evasion. We also identify the five major elements that characterize this problem, namely, the coordination method, the environment, the target, the robot and its sensor(s). These elements are used to systematically analyze the control techniques. The majority of the studied work is based on simulation and laboratory studies, which may not accurately reflect real-world operational conditions. Importantly, while our systematic analysis is focused on multitarget observation, our proposed classification is useful also for related multirobot applications.

Sources of heterogeneity in case-control studies on associations between statins, ACE-inhibitors, and proton pump inhibitors and risk of pneumonia.

PubMed

de Groot, Mark C H; Klungel, Olaf H; Leufkens, Hubert G M; van Dijk, Liset; Grobbee, Diederick E; van de Garde, Ewoudt M W

2014-10-01

The heterogeneity in case-control studies on the associations between community-acquired pneumonia (CAP) and ACE-inhibitors (ACEi), statins, and proton pump inhibitors (PPI) hampers translation to clinical practice. Our objective is to explore sources of this heterogeneity by applying a common protocol in different data settings. We conducted ten case-control studies using data from five different health care databases. Databases varied on type of patients (hospitalised vs. GP), level of case validity, and mode of exposure ascertainment (prescription or dispensing based). Identified CAP patients and controls were matched on age, gender, and calendar year. Conditional logistic regression was used to calculate odds ratios (OR) for the associations between the drugs of interest and CAP. Associations were adjusted by a common set of potential confounders. Data of 38,742 cases and 118,019 controls were studied. Comparable patterns of variation between case-control studies were observed for ACEi, statins and PPI use and pneumonia risk with adjusted ORs varying from 1.04 to 1.49, 0.82 to 1.50 and 1.16 to 2.71, respectively. Overall, higher ORs were found for hospitalised CAP patients matched to population controls versus GP CAP patients matched to population controls. Prevalence of drug exposure was higher in dispensing data versus prescription data. We show that case-control selection and methods of exposure ascertainment induce bias that cannot be adjusted for and to a considerable extent explain the heterogeneity in results obtained in case-control studies on statins, ACEi and PPIs and CAP. The common protocol approach helps to better understand sources of variation in observational studies.

Media coverage of medical journals: do the best articles make the news?

PubMed

Selvaraj, Senthil; Borkar, Durga S; Prasad, Vinay

2014-01-01

News coverage of medical research is followed closely by many Americans and affects the practice of medicine and influence of scientific research. Prior work has examined the quality of media coverage, but no investigation has characterized the choice of stories covered in a controlled manner. We examined whether the media systematically covers stories of weaker study design. We compared study characteristics of 75 clinically-oriented journal articles that received coverage in the top five newspapers by circulation against 75 clinically-oriented journal articles that appeared in the top five medical journals by impact factor over a similar timespan. Subgroup analysis was performed to determine whether differences between investigations from both sources varied by study type (randomized controlled trial [RCT] or observational study). Investigations receiving coverage from newspapers were less likely to be RCTs (17% vs. 35%, p = 0.016) and more likely to be observational studies (75% vs. 47%, p<0.001). No difference was observed in number of people studied (median: 1034 vs. 1901, p = 0.14) or length of follow-up (median: 1.80 vs. 1.00 years, p = 0.22). In subgroup analysis, observational studies from the media used smaller sample sizes (median: 1984 vs. 21136, p = 0.029) and were more likely to be cross-sectional (71% vs. 31%, p<0.001), while no differences were observed for RCTs. Newspapers were more likely to cover observational studies and less likely to cover RCTs than high impact journals. Additionally, when the media does cover observational studies, they select articles of inferior quality. Newspapers preferentially cover medical research with weaker methodology.

Genotoxic Evaluation of Mexican Welders Occupationally Exposed to Welding-Fumes Using the Micronucleus Test on Exfoliated Oral Mucosa Cells: A Cross-Sectional, Case-Control Study.

PubMed

Jara-Ettinger, Ana Cecilia; López-Tavera, Juan Carlos; Zavala-Cerna, María Guadalupe; Torres-Bugarín, Olivia

2015-01-01

An estimated 800,000 people worldwide are occupationally exposed to welding-fumes. Previous studies show that the exposure to such fumes is associated with damage to genetic material and increased cancer risk. In this study, we evaluate the genotoxic effect of welding-fumes using the Micronucleus Test on oral mucosa cells of Mexican welders. We conducted a cross-sectional, matched case-control study of n = 66 (33 exposed welders, and 33 healthy controls). Buccal mucosa smears were collected and stained with acridine orange, observed under 100x optical amplification with a fluorescence lamp, and a single-blinded observer counted the number of micronuclei and other nuclear abnormalities per 2,000 observed cells. We compared the frequencies of micronuclei and other nuclear abnormalities, and fitted generalised linear models to investigate the interactions between nuclear abnormalities and the exposure to welding-fumes, while controlling for smoking and age. Binucleated cells and condensed-chromatin cells showed statistically significant differences between cases and controls. The frequency of micronuclei and the rest of nuclear abnormalities (lobed-nuclei, pyknosis, karyolysis, and karyorrhexis) did not differ significantly between the groups. After adjusting for smoking, the regression results showed that the occurrence of binucleated cells could be predicted by the exposure to welding-fumes plus the presence of tobacco consumption; for the condensed-chromatin cells, our model showed that the exposure to welding-fumes is the only reliable predictor. Our findings suggest that Mexican welders who are occupationally exposed to welding-fumes have increased counts of binucleated and condensed-chromatin cells. Nevertheless, the frequencies of micronuclei and the rest of nuclear abnormalities did not differ between cases and controls. Further studies should shed more light on this subject.

Electromagnetic induction heating for single crystal graphene growth: morphology control by rapid heating and quenching

NASA Astrophysics Data System (ADS)

Wu, Chaoxing; Li, Fushan; Chen, Wei; Veeramalai, Chandrasekar Perumal; Ooi, Poh Choon; Guo, Tailiang

2015-03-01

The direct observation of single crystal graphene growth and its shape evolution is of fundamental importance to the understanding of graphene growth physicochemical mechanisms and the achievement of wafer-scale single crystalline graphene. Here we demonstrate the controlled formation of single crystal graphene with varying shapes, and directly observe the shape evolution of single crystal graphene by developing a localized-heating and rapid-quenching chemical vapor deposition (CVD) system based on electromagnetic induction heating. Importantly, rational control of circular, hexagonal, and dendritic single crystalline graphene domains can be readily obtained for the first time by changing the growth condition. Systematic studies suggest that the graphene nucleation only occurs during the initial stage, while the domain density is independent of the growth temperatures due to the surface-limiting effect. In addition, the direct observation of graphene domain shape evolution is employed for the identification of competing growth mechanisms including diffusion-limited, attachment-limited, and detachment-limited processes. Our study not only provides a novel method for morphology-controlled graphene synthesis, but also offers fundamental insights into the kinetics of single crystal graphene growth.

Unsymmetric Lanczos model reduction and linear state function observer for flexible structures

NASA Technical Reports Server (NTRS)

Su, Tzu-Jeng; Craig, Roy R., Jr.

1991-01-01

This report summarizes part of the research work accomplished during the second year of a two-year grant. The research, entitled 'Application of Lanczos Vectors to Control Design of Flexible Structures' concerns various ways to use Lanczos vectors and Krylov vectors to obtain reduced-order mathematical models for use in the dynamic response analyses and in control design studies. This report presents a one-sided, unsymmetric block Lanczos algorithm for model reduction of structural dynamics systems with unsymmetric damping matrix, and a control design procedure based on the theory of linear state function observers to design low-order controllers for flexible structures.

Quality of the parent-child interaction in young children with type 1 diabetes mellitus: study protocol.

PubMed

Nieuwesteeg, Anke M; Pouwer, Frans; van Bakel, Hedwig Ja; Emons, Wilco Hm; Aanstoot, Henk-Jan; Odink, Roelof; Hartman, Esther E

2011-04-14

In young children with type 1 diabetes mellitus (T1DM) parents have full responsibility for the diabetes-management of their child (e.g. blood glucose monitoring, and administering insulin). Behavioral tasks in childhood, such as developing autonomy, and oppositional behavior (e.g. refusing food) may interfere with the diabetes-management to achieve an optimal blood glucose control. Furthermore, higher blood glucose levels are related to more behavioral problems. So parents might need to negotiate with their child on the diabetes-management to avoid this direct negative effect. This interference, the negotiations, and the parent's responsibility for diabetes may negatively affect the quality of parent-child interaction. Nevertheless, there is little knowledge about the quality of interaction between parents and young children with T1DM, and the possible impact this may have on glycemic control and psychosocial functioning of the child. While widely used global parent-child interaction observational methods are available, there is a need for an observational tool specifically tailored to the interaction patterns of parents and children with T1DM. The main aim of this study is to construct a disease-specific observational method to assess diabetes-specific parent-child interaction. Additional aim is to explore whether the quality of parent-child interactions is associated with the glycemic control, and psychosocial functioning (resilience, behavioral problems, and quality of life). First, we will examine which situations are most suitable for observing diabetes-specific interactions. Then, these situations will be video-taped in a pilot study (N = 15). Observed behaviors are described into rating scales, with each scale describing characteristics of parent-child interactional behaviors. Next, we apply the observational tool on a larger scale for further evaluation of the instrument (N = 120). The parents are asked twice (with two years in between) to fill out questionnaires about psychosocial functioning of their child with T1DM. Furthermore, glycemic control (HbA1c) will be obtained from their medical records. A disease-specific observational tool will enable the detailed assessment of the quality of diabetes-specific parent-child interactions. The availability of such a tool will facilitate future (intervention) studies that will yield more knowledge about impact of parent-child interactions on psychosocial functioning, and glycemic control of children with T1DM.

Quality of the parent-child interaction in young children with type 1 diabetes mellitus: study protocol

PubMed Central

2011-01-01

Background In young children with type 1 diabetes mellitus (T1DM) parents have full responsibility for the diabetes-management of their child (e.g. blood glucose monitoring, and administering insulin). Behavioral tasks in childhood, such as developing autonomy, and oppositional behavior (e.g. refusing food) may interfere with the diabetes-management to achieve an optimal blood glucose control. Furthermore, higher blood glucose levels are related to more behavioral problems. So parents might need to negotiate with their child on the diabetes-management to avoid this direct negative effect. This interference, the negotiations, and the parent's responsibility for diabetes may negatively affect the quality of parent-child interaction. Nevertheless, there is little knowledge about the quality of interaction between parents and young children with T1DM, and the possible impact this may have on glycemic control and psychosocial functioning of the child. While widely used global parent-child interaction observational methods are available, there is a need for an observational tool specifically tailored to the interaction patterns of parents and children with T1DM. The main aim of this study is to construct a disease-specific observational method to assess diabetes-specific parent-child interaction. Additional aim is to explore whether the quality of parent-child interactions is associated with the glycemic control, and psychosocial functioning (resilience, behavioral problems, and quality of life). Methods/Design First, we will examine which situations are most suitable for observing diabetes-specific interactions. Then, these situations will be video-taped in a pilot study (N = 15). Observed behaviors are described into rating scales, with each scale describing characteristics of parent-child interactional behaviors. Next, we apply the observational tool on a larger scale for further evaluation of the instrument (N = 120). The parents are asked twice (with two years in between) to fill out questionnaires about psychosocial functioning of their child with T1DM. Furthermore, glycemic control (HbA1c) will be obtained from their medical records. Discussion A disease-specific observational tool will enable the detailed assessment of the quality of diabetes-specific parent-child interactions. The availability of such a tool will facilitate future (intervention) studies that will yield more knowledge about impact of parent-child interactions on psychosocial functioning, and glycemic control of children with T1DM. PMID:21492413

Reliability of movement control tests in the lumbar spine

PubMed Central

Luomajoki, Hannu; Kool, Jan; de Bruin, Eling D; Airaksinen, Olavi

2007-01-01

Background Movement control dysfunction [MCD] reduces active control of movements. Patients with MCD might form an important subgroup among patients with non specific low back pain. The diagnosis is based on the observation of active movements. Although widely used clinically, only a few studies have been performed to determine the test reliability. The aim of this study was to determine the inter- and intra-observer reliability of movement control dysfunction tests of the lumbar spine. Methods We videoed patients performing a standardized test battery consisting of 10 active movement tests for motor control in 27 patients with non specific low back pain and 13 patients with other diagnoses but without back pain. Four physiotherapists independently rated test performances as correct or incorrect per observation, blinded to all other patient information and to each other. The study was conducted in a private physiotherapy outpatient practice in Reinach, Switzerland. Kappa coefficients, percentage agreements and confidence intervals for inter- and intra-rater results were calculated. Results The kappa values for inter-tester reliability ranged between 0.24 – 0.71. Six tests out of ten showed a substantial reliability [k > 0.6]. Intra-tester reliability was between 0.51 – 0.96, all tests but one showed substantial reliability [k > 0.6]. Conclusion Physiotherapists were able to reliably rate most of the tests in this series of motor control tasks as being performed correctly or not, by viewing films of patients with and without back pain performing the task. PMID:17850669

Inhibitory control in bulimic-type eating disorders: a systematic review and meta-analysis.

PubMed

Wu, Mudan; Hartmann, Mechthild; Skunde, Mandy; Herzog, Wolfgang; Friederich, Hans-Christoph

2013-01-01

The aim of this meta-analysis was to summarise data from neuropsychological studies on inhibitory control to general and disease-salient (i.e., food/eating, body/shape) stimuli in bulimic-type eating disorders (EDs). A systematic literature search was conducted to identify eligible experimental studies. The outcome measures studied included the performance on established inhibitory control tasks in bulimic-type EDs. Effect sizes (Hedges' g) were pooled using random-effects models. For inhibitory control to general stimuli, 24 studies were included with a total of 563 bulimic-type ED patients: 439 had bulimia nervosa (BN), 42 had anorexia nervosa of the binge/purge subtype (AN-b), and 82 had binge eating disorder (BED). With respect to inhibitory control to disease-salient stimuli, 12 studies were included, representing a total of 218 BN patients. A meta-analysis of these studies showed decreased inhibitory control to general stimuli in bulimic-type EDs (g = -0.32). Subgroup analysis revealed impairments with a large effect in the AN-b group (g = -0.91), impairments with a small effect in the BN group (g = -0.26), and a non-significant effect in the BED group (g = -0.16). Greater impairments in inhibitory control were observed in BN patients when confronted with disease-salient stimuli (food/eating: g = -0.67; body/shape: g = -0.61). In conclusion, bulimic-type EDs showed impairments in inhibitory control to general stimuli with a small effect size. There was a significantly larger impairment in inhibitory control to disease salient stimuli observed in BN patients, constituting a medium effect size.

Mothers as Teachers: Instruction and Control Patterns Observed in Interactions of Middle-Class Mothers with Trainable Mentally Retarded and Nonretarded Children. Final Report Number 7.32.

ERIC Educational Resources Information Center

Dolley, Diane Greenough

A study was conducted to compare teaching and control patterns used by mothers of 4- to 6-year-old trainable mentally retarded (TMR) children to patterns used by mothers of nonretarded children, and to evaluate an analysis strategy identifying sequential behavior chains from observational data. Literature was explored on three topics: cognitive…

[Transitory hypothermia as early prognostic factor in term newborns with intrauterine growth retardation].

PubMed

Lazić-Mitrović, Tanja; Djukić, Milan; Cutura, Nedjo; Andjelić, Spaso; Curković, Aleksandar; Soldo, Vesna; Radlović, Nedeljko

2010-01-01

According to numerous researches, transitory hypothermia is a part of the neonatological energetic triangle and represents a significant prognostic factor within morbidity and mortality in newborns with intrauterine growth retardation (IUGR), that are, due to their characteristics, more inclined to transitory hypothermia. The aim of the study was an analysis of frequency of transitory hypothermia in term newborns with IUGR, as well as an analysis of frequency of the most frequent pathological conditions typical of IUGR newborns depending on the presence of transitory hypothermia after birth (hypoglycaemia, perinatal asphyxia, hyperbilirubinaemia and hypocalcaemia). The study included 143 term newborns with IUGR treated at the Neonatology Ward of the Gynaecology-Obstetrics Clinic "Narodni front", Belgrade. The newborns were divided into two groups: the one with registered transitory hypothermia--the observed group, and the one without transitory hypothermia--the control group. The data analysis included the analysis of the frequency of transitory hypothermia depending on gestation and body mass, as well as the analysis of pathological conditions (perinatal asphyxia, hypoglycaemia, hypocalcaemia, hyperbilirubinaemia) depending on the presence of hypothermia. The analysis was done by statistical tests of analytic and descriptive statistics. In morbidity structure dominate hypothermia (65.03%), hypoglycaemia (43.36%), perinatal asphyxia (37.76%), hyperbilirubinaemia (30.77%), hypocalcaemia (25.17%). There were 93 newborns in the observed group, and 50 in the control one. Mean value of the measured body temperature was 35.9 degrees C. 20 newborns (32.26%) had moderate hypothermia, and 73 newborns (67.74%) had mild hypothermia. In the observed group, average gestation was 39.0 weeks, and 39.6 (p < 0.01) in the control group. Average body mass at birth in the whole group was 2339 g: 2214 g in the observed and 2571 g in the control group. The frequency of hypoglycaemia in the observed group was 53.8%, and 24% in the control group (p < 0.01). In the observed group, the frequency of pH < 7.25 was 38.71%, and 14% in the control group (p < 0.05). The frequency of hyperbilirubinaemia was 38.71% in the observed group, and 16% in the control group (p < 0.01). The frequency of hypocalcaemia was 32.26% in the observed, and 12% in the control group (p < 0.01). Transitory hypothermia in the first ten hours of life represents a significant risk factor for deepening hypoglycaemia, asphyxia, hyperbilirubinaemia and hypocalcaemia in term newborns with IUGR.

Childhood brain tumours and use of mobile phones: comparison of a case-control study with incidence data.

PubMed

Aydin, Denis; Feychting, Maria; Schüz, Joachim; Röösli, Martin

2012-05-20

The first case-control study on mobile phone use and brain tumour risk among children and adolescents (CEFALO study) has recently been published. In a commentary published in Environmental Health, Söderqvist and colleagues argued that CEFALO suggests an increased brain tumour risk in relation to wireless phone use. In this article, we respond and show why consistency checks of case-control study results with observed time trends of incidence rates are essential, given the well described limitations of case-control studies and the steep increase of mobile phone use among children and adolescents during the last decade. There is no plausible explanation of how a notably increased risk from use of wireless phones would correspond to the relatively stable incidence time trends for brain tumours among children and adolescents observed in the Nordic countries. Nevertheless, an increased risk restricted to heavy mobile phone use, to very early life exposure, or to rare subtypes of brain tumours may be compatible with stable incidence trends at this time and thus further monitoring of childhood brain tumour incidence rate time trends is warranted.

Developmental Transitions as Successive Reorganizations of a Control Hierarchy.

ERIC Educational Resources Information Center

Plooij, Frans X.; And Others

1990-01-01

Describes two studies involving chimpanzee mother-infant pairs in Tanzania between 1980 and 1987 that implemented control theory concepts. The first identified behavioral development in infant chimps; the second observed the growth of independence and parenting patterns. Concludes that the hierarchy of controlled variables develops consecutively…

Measurement of the Perception of Control during Continuous Movement using Electroencephalography

PubMed Central

Wen, Wen; Yamashita, Atsushi; Asama, Hajime

2017-01-01

“Sense of control” refers to the subjective feeling of control over external events. Numerous neuropsychological studies have investigated the neural basis of the sense of control during action performance; however, most previous studies have focused on responses to a single discrete action outcome rather than real-time processing of action-outcome sequences. In the present study, we aimed to identify whether certain patterns of brain activation are associated with the perceived control during continuous movement. We recorded electroencephalography (EEG) signals while participants continuously moved a right-handed mouse in an attempt to control multiple visual stimuli. When participants perceived a sense of control over the stimuli, we observed a positive potential approximately 550 ms after the onset of movement, while no similar potential was observed when participants reported a lack of control. The appearance of this potential was consistent with the time window of awareness of control in a behavioral test using the same task, and likely reflected the explicit allocation of attention to control. Moreover, we found that the alpha-mu rhythm, which is linked to sensorimotor processing, was significantly suppressed after participants came to a conclusion regarding the level of control, regardless of whether control or lack of control was perceived. In summary, our results suggest that the late positive potential after the onset of the movement and the suppression of alpha-mu rhythm can be used as markers of the perception of control during continuous action performance and feedback monitoring. PMID:28798677

Speed tracking control of pneumatic motor servo systems using observation-based adaptive dynamic sliding-mode control

NASA Astrophysics Data System (ADS)

Chen, Syuan-Yi; Gong, Sheng-Sian

2017-09-01

This study aims to develop an adaptive high-precision control system for controlling the speed of a vane-type air motor (VAM) pneumatic servo system. In practice, the rotor speed of a VAM depends on the input mass air flow, which can be controlled by the effective orifice area (EOA) of an electronic throttle valve (ETV). As the control variable of a second-order pneumatic system is the integral of the EOA, an observation-based adaptive dynamic sliding-mode control (ADSMC) system is proposed to derive the differential of the control variable, namely, the EOA control signal. In the ADSMC system, a proportional-integral-derivative fuzzy neural network (PIDFNN) observer is used to achieve an ideal dynamic sliding-mode control (DSMC), and a supervisor compensator is designed to eliminate the approximation error. As a result, the ADSMC incorporates the robustness of a DSMC and the online learning ability of a PIDFNN. To ensure the convergence of the tracking error, a Lyapunov-based analytical method is employed to obtain the adaptive algorithms required to tune the control parameters of the online ADSMC system. Finally, our experimental results demonstrate the precision and robustness of the ADSMC system for highly nonlinear and time-varying VAM pneumatic servo systems.

Altered neuromuscular control and ankle joint kinematics during walking in subjects with functional instability of the ankle joint.

PubMed

Delahunt, Eamonn; Monaghan, Kenneth; Caulfield, Brian

2006-12-01

The ankle joint requires very precise neuromuscular control during the transition from terminal swing to the early stance phase of the gait cycle. Altered ankle joint arthrokinematics and muscular activity have been cited as potential factors that may lead to an inversion sprain during the aforementioned time periods. However, to date, no study has investigated patterns of muscle activity and 3D joint kinematics simultaneously in a group of subjects with functional instability compared with a noninjured control group during these phases of the gait cycle. To compare the patterns of lower limb 3D joint kinematics and electromyographic activity during treadmill walking in a group of subjects with functional instability with those observed in a control group. Controlled laboratory study. Three-dimensional angular velocities and displacements of the hip, knee, and ankle joints, as well as surface electromyography of the rectus femoris, peroneus longus, tibialis anterior, and soleus muscles, were recorded simultaneously while subjects walked on a treadmill at a velocity of 4 km/h. Before heel strike, subjects with functional instability exhibited a decrease in vertical foot-floor clearance (12.62 vs 22.84 mm; P < .05), as well as exhibiting a more inverted position of the ankle joint before, at, and immediately after heel strike (1.69 degrees , 2.10 degrees , and -0.09 degrees vs -1.43 degrees , -1.43 degrees , and -2.78 degrees , respectively [minus value = eversion]; P < .05) compared with controls. Subjects with functional instability were also observed to have an increase in peroneus longus integral electromyography during the post-heel strike time period (107.91%.millisecond vs 64.53%.millisecond; P < .01). The altered kinematics observed in this study could explain the reason subjects with functional instability experience repeated episodes of ankle inversion injury in situations with only slight or no external provocation. It is hypothesized that the observed increase in peroneus longus activity may be the result of a change in preprogrammed feed-forward motor control.

Misclassification of Case-Control Studies in Neurosurgery and Proposed Solutions.

PubMed

Esene, Ignatius Ngene; Mbuagbaw, Lawrence; Dechambenoit, Gilbert; Reda, Wael; Kalangu, Kazadi K

2018-04-01

Case-control studies (CCS) and cohort studies (CS) are common research designs in neurosurgery. But the term case-control study is frequently misused in the neurosurgical literature, with many articles reported as CCS, even although their methodology does not respect the basic components of a CCS. We sought to estimate the extent of these discrepancies in neurosurgical literature, explore factors contributing to mislabeling, and shed some light on study design reporting. We identified 31 top-ranking pure neurosurgical journals and searched them for articles reported as CCS, either in the title or in the abstract. The articles were read to determine if they really were CCS according to STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) guidelines. Article assessment was conducted in duplicate (agreement [κ statistics] = 99.82%). Two hundred and twenty-four articles met our inclusion criteria, 133 of which (59.38%) correctly labeled the case-control design, whereas 91 (40.62%) misclassified this study design. Cohort studies (CS) were the most common design mislabeled as case-control studies in 76 articles (33.93%), 57 of which (25.45%) were retrospective CS. The mislabeling of CCS impairs the appropriate indexing, classification, and sorting of evidence. Mislabeling CS for CCS leads to a downgrading of evidence as CS represent the highest level of evidence for observational studies. Odds ratios instead of relative risk are reported for these studies, resulting in a distortion of the measurement of the effect size, compounded when these are summarized in systematic reviews and pooled in meta-analyses. Many studies reported as CCS are not true CCS. Reporting guidelines should include items that ensure that studies are labeled correctly. STROBE guidelines should be implemented in assessment of observational studies. Researchers in neurosurgery need better training in research methods and terminology. We also recommend accrued vigilance from reviewers and editors. Copyright © 2018 Elsevier Inc. All rights reserved.

Risk of stroke in patients with patent foramen ovale: an updated meta-analysis of observational studies.

PubMed

Ma, Bing; Liu, Guangcong; Chen, Xin; Zhang, Jianming; Liu, Yiting; Shi, Jingpu

2014-01-01

Although patent foramen ovale (PFO) is considered to be associated with cryptogenic stroke (CS), there remains an ongoing disputation on this issue because of unstable results from randomized controlled trials. The aim of this study was to reassess the PFO effect on stroke through observational data. An electronic search of PubMed, Web of Science, and China National Knowledge Infrastructure (CNKI) were finished. Only case-control studies and cohort studies in Chinese or English were included in the analysis. Then random-effected meta-analysis models were performed to assess the association between PFO and stroke. Twelve case-control studies and 6 cohort studies were eligible. Case-control studies showed strong association between PFO and CS (odds ratio [OR]: 2.94, 95% confidence interval [CI]: 2.06, 4.20; P < .001), but cohort studies failed to demonstrate a significant association (hazard ratio [HR]: 1.28, 95% CI: .91, 1.80; P = .155). Subgroup analysis revealed that the pooled OR decreased significantly when the region was limited to the United States (OR: 1.52, 95% CI: 1.00, 2.32; P = .083). OR of studies that adjusted major confounders was 1.74 (95% CI: 1.22, 2.47; P = .119) and high-quality studies was 1.68 (95% CI: 1.14, 2.47; P = .072). For cohort studies, a weak statistical association was observed in using transesophageal echocardiography (TEE) studies (HR: 1.45, 95% CI: 1.06, 2.01; P = .138) and follow-up years less than 4 years' studies (HR: 1.45, 95% CI: 1.00, 2.09; P = .064). Although case-control studies still show a positive effect of PFO on stroke, the results of cohort challenged the credibility. Further trial data are needed to confirm the effect of PFO on stroke. Copyright © 2014 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Clinical efficacy of a spray containing hyaluronic Acid and dexpanthenol after surgery in the nasal cavity (septoplasty, simple ethmoid sinus surgery, and turbinate surgery).

PubMed

Gouteva, Ina; Shah-Hosseini, Kija; Meiser, Peter

2014-01-01

Background. This prospective, controlled, parallel-group observational study investigated the efficacy of a spray containing hyaluronic acid and dexpanthenol to optimise regular treatment after nasal cavity surgery in 49 patients with chronic rhinosinusitis. Methods. The control group received standard therapy. Mucosal regeneration was determined using rhinoscopy sum score (RSS). Pre- and postoperative nasal patency was tested using anterior rhinomanometry. The participants were questioned about their symptoms. Results. Regarding all RSS parameters (dryness, dried nasal mucus, fibrin deposition, and obstruction), mucosal regeneration achieved good final results in both groups, tending to a better improvement through the spray application, without statistically significant differences during the whole assessment period, the mean values being 7.04, 5.00, 3.66, and 3.00 (intervention group) and 7.09, 5.14, 4.36, and 3.33 (control group). No statistically significant benefit was identified for nasal breathing, foreign body sensation, and average rhinomanometric volume flow, which improved by 12.31% (control group) and 11.24% (nasal spray group). Conclusion. The investigational product may have additional benefit on postoperative mucosal regeneration compared to standard cleaning procedures alone. However, no statistically significant advantage could be observed in this observational study. Double-blind, controlled studies with larger populations will be necessary to evaluate the efficacy of this treatment modality.

Clinical Efficacy of a Spray Containing Hyaluronic Acid and Dexpanthenol after Surgery in the Nasal Cavity (Septoplasty, Simple Ethmoid Sinus Surgery, and Turbinate Surgery)

PubMed Central

2014-01-01

Background. This prospective, controlled, parallel-group observational study investigated the efficacy of a spray containing hyaluronic acid and dexpanthenol to optimise regular treatment after nasal cavity surgery in 49 patients with chronic rhinosinusitis. Methods. The control group received standard therapy. Mucosal regeneration was determined using rhinoscopy sum score (RSS). Pre- and postoperative nasal patency was tested using anterior rhinomanometry. The participants were questioned about their symptoms. Results. Regarding all RSS parameters (dryness, dried nasal mucus, fibrin deposition, and obstruction), mucosal regeneration achieved good final results in both groups, tending to a better improvement through the spray application, without statistically significant differences during the whole assessment period, the mean values being 7.04, 5.00, 3.66, and 3.00 (intervention group) and 7.09, 5.14, 4.36, and 3.33 (control group). No statistically significant benefit was identified for nasal breathing, foreign body sensation, and average rhinomanometric volume flow, which improved by 12.31% (control group) and 11.24% (nasal spray group). Conclusion. The investigational product may have additional benefit on postoperative mucosal regeneration compared to standard cleaning procedures alone. However, no statistically significant advantage could be observed in this observational study. Double-blind, controlled studies with larger populations will be necessary to evaluate the efficacy of this treatment modality. PMID:25104962

40 CFR 798.4350 - Inhalation developmental toxicity study.

Code of Federal Regulations, 2012 CFR

2012-07-01

...) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) HEALTH EFFECTS TESTING GUIDELINES Specific Organ/Tissue... million (ppm). (6) “No-observed-effect level” is the maximum concentration in a test which produces no observed adverse effects. A no-observed-effect level is expressed in terms of weight or volume of test...

40 CFR 798.4350 - Inhalation developmental toxicity study.

Code of Federal Regulations, 2014 CFR

2014-07-01

...) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) HEALTH EFFECTS TESTING GUIDELINES Specific Organ/Tissue... million (ppm). (6) “No-observed-effect level” is the maximum concentration in a test which produces no observed adverse effects. A no-observed-effect level is expressed in terms of weight or volume of test...

40 CFR 798.4350 - Inhalation developmental toxicity study.

Code of Federal Regulations, 2013 CFR

2013-07-01

...) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) HEALTH EFFECTS TESTING GUIDELINES Specific Organ/Tissue... million (ppm). (6) “No-observed-effect level” is the maximum concentration in a test which produces no observed adverse effects. A no-observed-effect level is expressed in terms of weight or volume of test...

Quality standards for real-world research. Focus on observational database studies of comparative effectiveness.

PubMed

Roche, Nicolas; Reddel, Helen; Martin, Richard; Brusselle, Guy; Papi, Alberto; Thomas, Mike; Postma, Dirjke; Thomas, Vicky; Rand, Cynthia; Chisholm, Alison; Price, David

2014-02-01

Real-world research can use observational or clinical trial designs, in both cases putting emphasis on high external validity, to complement the classical efficacy randomized controlled trials (RCTs) with high internal validity. Real-world research is made necessary by the variety of factors that can play an important a role in modulating effectiveness in real life but are often tightly controlled in RCTs, such as comorbidities and concomitant treatments, adherence, inhalation technique, access to care, strength of doctor-caregiver communication, and socio-economic and other organizational factors. Real-world studies belong to two main categories: pragmatic trials and observational studies, which can be prospective or retrospective. Focusing on comparative database observational studies, the process aimed at ensuring high-quality research can be divided into three parts: preparation of research, analyses and reporting, and discussion of results. Key points include a priori planning of data collection and analyses, identification of appropriate database(s), proper outcomes definition, study registration with commitment to publish, bias minimization through matching and adjustment processes accounting for potential confounders, and sensitivity analyses testing the robustness of results. When these conditions are met, observational database studies can reach a sufficient level of evidence to help create guidelines (i.e., clinical and regulatory decision-making).

Oculomotor capture during real-world scene viewing depends on cognitive load.

PubMed

Matsukura, Michi; Brockmole, James R; Boot, Walter R; Henderson, John M

2011-03-25

It has been claimed that gaze control during scene viewing is largely governed by stimulus-driven, bottom-up selection mechanisms. Recent research, however, has strongly suggested that observers' top-down control plays a dominant role in attentional prioritization in scenes. A notable exception to this strong top-down control is oculomotor capture, where visual transients in a scene draw the eyes. One way to test whether oculomotor capture during scene viewing is independent of an observer's top-down goal setting is to reduce observers' cognitive resource availability. In the present study, we examined whether increasing observers' cognitive load influences the frequency and speed of oculomotor capture during scene viewing. In Experiment 1, we tested whether increasing observers' cognitive load modulates the degree of oculomotor capture by a new object suddenly appeared in a scene. Similarly, in Experiment 2, we tested whether increasing observers' cognitive load modulates the degree of oculomotor capture by an object's color change. In both experiments, the degree of oculomotor capture decreased as observers' cognitive resources were reduced. These results suggest that oculomotor capture during scene viewing is dependent on observers' top-down selection mechanisms. Copyright © 2011 Elsevier Ltd. All rights reserved.

Observer-based higher order sliding mode control of power factor in three-phase AC/DC converter for hybrid electric vehicle applications

NASA Astrophysics Data System (ADS)

Liu, Jianxing; Laghrouche, Salah; Wack, Maxime

2014-06-01

In this paper, a full-bridge boost power converter topology is studied for power factor control, using output higher order sliding mode control. The AC/DC converters are used for charging the battery and super-capacitor in hybrid electric vehicles from the utility. The proposed control forces the input currents to track the desired values, which can control the output voltage while keeping the power factor close to one. Super-twisting sliding mode observer is employed to estimate the input currents and load resistance only from the measurement of output voltage. Lyapunov analysis shows the asymptotic convergence of the closed-loop system to zero. Multi-rate simulation illustrates the effectiveness and robustness of the proposed controller in the presence of measurement noise.

A randomized intervention trial to reduce mechanical exposures in the Colombian flower industry.

PubMed

Barrero, L H; Ceballos, C; Ellegast, R; Pulido, J A; Monroy, M; Berrio, S; Quintana, L A

2014-01-01

Evidence on effectiveness of ergonomic interventions to reduce mechanical demands of the upper extremity is scarce in agriculture. To conduct an ergonomic intervention to reduce mechanical exposures on workers during manual flower cutting, while emphasizing postural education and reduction of force requirements. Seventy seven workers (20 to 55 years old; 80% women) from six companies that cultivate roses participated in this study. Participants from three companies were randomly assigned to control and intervention groups. A postural education program and a maintenance program was designed and implemented in the intervention group aiming to achieve more neutral postures of the wrist and forearm and to reduce force requirements during rose cutting. Changes in self-reported effort and upper extremity postures, kinematics and muscular activity between baseline and follow-up assessments were evaluated. Most of the observed changes in the evaluated mechanical exposures were moderate for both groups. The intervention group showed differential improvements compared to the control group for 95th percentile forearm pronation (intervention group went from 50.6 to 35.6°; control group went from 18.4 to 34.7°); and to some degree for the maximum wrist radial deviation (the intervention group went from 17° to 7.6°; control group went from 10.1° to 7.8°). Also, the mean elbow flexion for the control group was reduced from 62.3 to 48.4°, whereas it increased from 52.2 to 57.3° in the intervention group. No differential changes between the intervention and control groups were observed for the kinematic variables, except for an unexpected reduction in the 95th percentile velocity of wrist flexion-extension in the control group, which was not observed in the intervention group. Lastly, although observed changes in muscular activity were not statistically significant, improvements were observed for the intervention group for the flexor and extensor carpi radialis and the flexor carpi ulnaris; although the opposite was true for the extensor carpi ulnaris. Important although sometimes mixed results were achieved with this field intervention, focusing on postural and force requirement demands. The positive results are encouraging considering the presence of typical limitations observed in field intervention studies.

Exercising self-control increases approach motivation.

PubMed

Schmeichel, Brandon J; Harmon-Jones, Cindy; Harmon-Jones, Eddie

2010-07-01

The present research tested the hypothesis that exercising self-control causes an increase in approach motivation. Study 1 found that exercising (vs. not exercising) self-control increases self-reported approach motivation. Study 2a identified a behavior--betting on low-stakes gambles--that is correlated with approach motivation but is relatively uncorrelated with self-control, and Study 2b observed that exercising self-control temporarily increases this behavior. Last, Study 3 found that exercising self-control facilitates the perception of a reward-relevant symbol (i.e., a dollar sign) but not a reward-irrelevant symbol (i.e., a percent sign). Altogether, these results support the hypothesis that exercising self-control temporarily increases approach motivation. Failures of self-control that follow from prior efforts at self-control (i.e., ego depletion) may be explained in part by increased approach motivation.

Does behaviour modification affect post-stroke risk factor control? Three-year follow-up of a randomized controlled trial.

PubMed

McManus, Julie Ann; Craig, Alison; McAlpine, Christine; Langhorne, Peter; Ellis, Graham

2009-02-01

Little is known about the long-term effectiveness after stroke of interventions for behaviour modification and ensuring concordance with therapies. We describe a follow-up study of a previous randomized controlled trial of a brief period of behaviour modification. The aim of this study was to determine outcomes three years after the initial intervention. Survivors of the original cohort were contacted and asked to attend for follow-up interview, within a geriatric day hospital. This study was carried out in the Geriatric Day Hospital at Stobhill Hospital, Balornock Road, Glasgow. Details of risk factor control, including blood pressure, cholesterol levels and diabetic control, were assessed. Questionnaires used in the initial study were repeated including the Geriatric Depression Scale score, Euroqol Perceived Health Status and Stroke Services Satisfaction Questionnaire. Primary outcome was collective risk factor control. Clinical outcomes including recurrent cerebrovascular events, medication persistence and perceived health status were also recorded. Mean length of follow-up was 3.6 years (SD 0.43). Of the 205 patients enrolled in the initial study, 102 patients attended for repeat interview(49 intervention/53 control). There were no significant differences in the percentage of controlled risk factors between groups (intervention 51.7% versus control 55.9%, P = 0.53). Similarities were observed in the number of recurrent clinical events and medication persistence between groups. No overall difference was observed in perceived health status, satisfaction with care or depression scores. Brief intervention with respect to behaviour modification and risk factor control does not appear to have any long-term benefit. These results must be cautiously interpreted in light of the small study number and further research is required.

Sliding mode disturbance observer-enhanced adaptive control for the air-breathing hypersonic flight vehicle

NASA Astrophysics Data System (ADS)

An, Hao; Wang, Changhong; Fidan, Baris

2017-10-01

This paper presents a backstepping procedure to design an adaptive controller for the air-breathing hypersonic flight vehicle (AHFV) subject to external disturbances and actuator saturations. In each step, a sliding mode exact disturbance observer (SMEDO) is exploited to exactly estimate the lumped disturbance in finite time. Specific dynamics are introduced to handle the possible actuator saturations. Based on SMEDO and introduced dynamics, an adaptive control law is designed, along with the consideration on ;explosion of complexity; in backstepping design. The developed controller is equipped with fast disturbance rejection and great capability to accommodate the saturated actuators, which also lead to a wider application scope. A simulation study is provided to show the effectiveness and superiority of the proposed controller.

Understanding the use of emergency department and urgent care services by diabetic patients of a Family Medicine Health Team: a retrospective observational study.

PubMed

Ward, Matthew

2017-03-01

Aim To understand the frequency, urgency, and rationale of emergency department and urgent care (ED/UC) use by diabetic patients of a Family Medicine Health Team (FHT). A retrospective, observational study with comparison control groups was conducted from 1 January 2013 to 31 December 2014. A total of 693 diabetic patients were compared with two, age-standardized non-diabetic groups: one with a higher disease burden based on International Classification of Diseases 9 diagnoses and the other from a randomized patient pool. Findings The diabetic group utilized ED/UC services 1.25 and 1.92 times more often than the two control populations, consistent with that observed in other studies. Canadian Triage and Acuity Scale scores were essentially the same for the diabetic population. Only 3.1% of visits were for diabetic related emergencies, in contrast to the expected 23% by surveyed physicians of the FHT. Diabetic patient's sought treatment for cellulitis, wounds, abscesses, and infections more often than the control populations.

Is plasma GABA level a biomarker of Post-Traumatic Stress Disorder (PTSD) severity? A preliminary study.

PubMed

Trousselard, Marion; Lefebvre, Bertrand; Caillet, Lionel; Andruetan, Yann; de Montleau, Franck; Denis, Josiane; Canini, Frédéric

2016-07-30

An increased reactivity to the environment is observed in Post-Traumatic Stress Disorder (PTSD). It would be related to impairment of the Gamma Amino Butyric Acid (GABA) neurotransmission. The study aimed to evaluate plasma GABA concentration as a candidate for PTSD severity biomarker. This hypothesis was studied in 17 PTSD patients and 17 healthy Controls using classic and emotional Stroop paradigms. Plasma GABA concentrations were assessed before and after both Stroop tests to evaluate GABA basal tone and GABA reactivity (change in GABAp), respectively. During baseline, PTSD had lower plasma GABA concentrations than the Controls. After the Stroop conflicts GABA reactivity was also lower in PTSD than in the Controls. The GABA baseline tone was negatively correlated with the severity of the PTSD symptoms. This relation was only marginally observed for GABA reactivity. The results produced a trend due to the small size of the sample compared to the number of statistical results given. Altogether, the reduced GABA concentration observed in PTSD could be considered as a possible biomarker for PTSD severity. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Self-reported empathy and neural activity during action imitation and observation in schizophrenia

PubMed Central

Horan, William P.; Iacoboni, Marco; Cross, Katy A.; Korb, Alex; Lee, Junghee; Nori, Poorang; Quintana, Javier; Wynn, Jonathan K.; Green, Michael F.

2014-01-01

Introduction Although social cognitive impairments are key determinants of functional outcome in schizophrenia their neural bases are poorly understood. This study investigated neural activity during imitation and observation of finger movements and facial expressions in schizophrenia, and their correlates with self-reported empathy. Methods 23 schizophrenia outpatients and 23 healthy controls were studied with functional magnetic resonance imaging (fMRI) while they imitated, executed, or simply observed finger movements and facial emotional expressions. Between-group activation differences, as well as relationships between activation and self-reported empathy, were evaluated. Results Both patients and controls similarly activated neural systems previously associated with these tasks. We found no significant between-group differences in task-related activations. There were, however, between-group differences in the correlation between self-reported empathy and right inferior frontal (pars opercularis) activity during observation of facial emotional expressions. As in previous studies, controls demonstrated a positive association between brain activity and empathy scores. In contrast, the pattern in the patient group reflected a negative association between brain activity and empathy. Conclusions Although patients with schizophrenia demonstrated largely normal patterns of neural activation across the finger movement and facial expression tasks, they reported decreased self perceived empathy and failed to show the typical relationship between neural activity and self-reported empathy seen in controls. These findings suggest that patients show a disjunction between automatic neural responses to low level social cues and higher level, integrative social cognitive processes involved in self-perceived empathy. PMID:25009771

Self-reported empathy and neural activity during action imitation and observation in schizophrenia.

PubMed

Horan, William P; Iacoboni, Marco; Cross, Katy A; Korb, Alex; Lee, Junghee; Nori, Poorang; Quintana, Javier; Wynn, Jonathan K; Green, Michael F

2014-01-01

Although social cognitive impairments are key determinants of functional outcome in schizophrenia their neural bases are poorly understood. This study investigated neural activity during imitation and observation of finger movements and facial expressions in schizophrenia, and their correlates with self-reported empathy. 23 schizophrenia outpatients and 23 healthy controls were studied with functional magnetic resonance imaging (fMRI) while they imitated, executed, or simply observed finger movements and facial emotional expressions. Between-group activation differences, as well as relationships between activation and self-reported empathy, were evaluated. Both patients and controls similarly activated neural systems previously associated with these tasks. We found no significant between-group differences in task-related activations. There were, however, between-group differences in the correlation between self-reported empathy and right inferior frontal (pars opercularis) activity during observation of facial emotional expressions. As in previous studies, controls demonstrated a positive association between brain activity and empathy scores. In contrast, the pattern in the patient group reflected a negative association between brain activity and empathy. Although patients with schizophrenia demonstrated largely normal patterns of neural activation across the finger movement and facial expression tasks, they reported decreased self perceived empathy and failed to show the typical relationship between neural activity and self-reported empathy seen in controls. These findings suggest that patients show a disjunction between automatic neural responses to low level social cues and higher level, integrative social cognitive processes involved in self-perceived empathy.

A randomized controlled trial of an intervention program to Brazilian mothers who use corporal punishment.

PubMed

Santini, Paolla Magioni; Williams, Lucia C A

2017-09-01

This study evaluated a positive parenting program to Brazilian mothers who used corporal punishment with their children. The intervention was conducted in four agencies serving vulnerable children, and at a home replica laboratory at the University. Mothers who admitted using corporal punishment were randomly assigned between experimental (n=20) and control group (n=20). The program consisted of 12 individual sessions using one unit from Projeto Parceria (Partnership Project), with specific guidelines and materials on positive parenting, followed by observational sessions of mother-child interaction with live coaching and a video feedback session in the lab. The study used an equivalent group experimental design with pre/post-test and follow-up, in randomized controlled trials. Measures involved: Initial Interview; Strengths and Difficulties Questionnaire (SDQ) - parent and child versions; Beck Depression Inventory (BDI); observational sessions with a protocol; and a Program Evaluation by participants. Analysis of mixed models for repeated measures revealed significant positive effects on the BDI and SDQ total scores, as well as less Conduct problems and Hyperactivity in SDQ measures from the experimental group mothers, comparing pre with post-test. Observational data also indicated significant improvement in positive interaction from the experimental group mothers at post-test, in comparison with controls. No significant results were found, however, in children's observational measures. Limitations of the study involved using a restricted sample, among others. Implications for future research are suggested. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Effects of Social Influence on Nurses' Hand Hygiene Behaviors.

PubMed

Piras, Susan E; Minnick, Ann; Lauderdale, Jana; Dietrich, Mary S; Vogus, Timothy J

2018-04-01

The aim of this article is to describe the associations of nurses' hand hygiene (HH) attitudes, subjective norms, and perceived behavioral control with observed and self-reported HH behavior. Hand hygiene is an essential strategy to prevent healthcare-associated infections. Despite tremendous efforts, nurses' HH adherence rates remain suboptimal. This quantitative descriptive study of ICU nurses in the southeastern United States was guided by the theory of planned behavior. The self-administered Patient Safety Opinion Survey and iScrub application, which facilitates observation, comprised the data set. Nurses' observed HH median was 55%; tendency to self-report was a much higher 90%. Subjective norm and perceived control scores were associated with observed and self-reported HH (P < .05) but not attitude scores or reports of intention. Nurses' subjective norm and perceived control are associated with observed and self-reported HH performance. Healthcare workers overestimate their HH performance. Findings suggest future research to explore manipulators of these variables to change nurses' HH behavior.

Suboptimal distributed control and estimation: application to a four coupled tanks system

NASA Astrophysics Data System (ADS)

Orihuela, Luis; Millán, Pablo; Vivas, Carlos; Rubio, Francisco R.

2016-06-01

The paper proposes an innovative estimation and control scheme that enables the distributed monitoring and control of large-scale processes. The proposed approach considers a discrete linear time-invariant process controlled by a network of agents that may both collect information about the evolution of the plant and apply control actions to drive its behaviour. The problem makes full sense when local observability/controllability is not assumed and the communication between agents can be exploited to reach system-wide goals. Additionally, to reduce agents bandwidth requirements and power consumption, an event-based communication policy is studied. The design procedure guarantees system stability, allowing the designer to trade-off performance, control effort and communication requirements. The obtained controllers and observers are implemented in a fully distributed fashion. To illustrate the performance of the proposed technique, experimental results on a quadruple-tank process are provided.

Prevalence of food sensitization and probable food allergy among adults in India: the EuroPrevall INCO study.

PubMed

Mahesh, P A; Wong, Gary W K; Ogorodova, L; Potts, J; Leung, T F; Fedorova, O; Holla, Amrutha D; Fernandez-Rivas, M; Clare Mills, E N; Kummeling, I; Versteeg, S A; van Ree, R; Yazdanbakhsh, M; Burney, P

2016-07-01

Data are lacking regarding the prevalence of food sensitization and probable food allergy among general population in India. We report the prevalence of sensitization and probable food allergy to 24 common foods among adults from general population in Karnataka, South India. The study was conducted in two stages: a screening study and a case-control study. A total of 11 791 adults in age group 20-54 were randomly sampled from general population in South India and answered a screening questionnaire. A total of 588 subjects (236 cases and 352 controls) participated in the case-control study involving a detailed questionnaire and specific IgE estimation for 24 common foods. A high level of sensitization (26.5%) was observed for most of the foods in the general population, higher than that observed among adults in Europe, except for those foods that cross-react with birch pollen. Most of the sensitization was observed in subjects who had total IgE above the median IgE level. A high level of cross-reactivity was observed among different pollens and foods and among foods. The prevalence of probable food allergy (self-reports of adverse symptoms after the consumption of food and specific IgE to the same food) was 1.2%, which was mainly accounted for cow's milk (0.5%) and apple (0.5%). Very high levels of sensitization were observed for most foods, including those not commonly consumed in the general population. For the levels of sensitization, the prevalence of probable food allergy was low. This disassociation needs to be further explored in future studies. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Age Related Differences in Metacognitive Control: Role of Executive Functioning

ERIC Educational Resources Information Center

Souchay, Celine; Isingrini, Michel

2004-01-01

To examine whether aging affects metacognitive control, elderly and young adults carried out a readiness-recall task, in which subjects monitor their own learning procedure, allowing strategy manipulation (study time and rehearsal) to be measured. Age differences were observed in metamemory control performance. Younger adults were found to be…

Control Variate Estimators of Survivor Growth from Point Samples

Treesearch

Francis A. Roesch; Paul C. van Deusen

1993-01-01

Two estimators of the control variate type for survivor growth from remeasured point samples are proposed and compared with more familiar estimators. The large reductionsin variance, observed in many cases forestimators constructed with control variates, arealso realized in thisapplication. A simulation study yielded consistent reductions in variance which were often...

Interlanguage Phonology: Acquisition of Timing Control in Japanese.

ERIC Educational Resources Information Center

Toda, Takako

1994-01-01

Studies the acquisition of timing control by Australians enrolled in first-year Japanese. Instrumental techniques are used to observe segment duration and pitch patterns in the speech production of learners and native speakers. Results indicate the learners can control timing, but their phonetic realization differs from that of native speakers.…

Effectiveness of Haemophilus influenzae type b vaccines administered according to various schedules: systematic review and meta-analysis of observational data.

PubMed

Jackson, Charlotte; Mann, Andrea; Mangtani, Punam; Fine, Paul

2013-11-01

Conjugate vaccines against Haemophilus influenzae type b (Hib) are widely used. The full implications of Hib vaccination schedule for vaccine effectiveness (VE) are unclear. We searched the literature for observational studies reporting the effectiveness of conjugate Hib vaccines administered according to different schedules. We summarized dose-specific VE estimates, where appropriate, using random effects meta-analysis. Thirty-one eligible articles (reporting 30 studies conducted in 17 countries) were identified. Meta-analysis of case-control studies using community controls produced VE estimates against Hib meningitis of 55% (95% confidence interval: 2-80%, based on 3 studies), 96% (86-99%, 3 studies) and 96% (86-99%, 4 studies) after 1, 2 and 3 doses of vaccines other than the polyribosyl ribitol phosphate outer membrane protein vaccine. Estimates were similar using hospital controls. VE against invasive Hib disease in case-control studies was estimated as 59% (30-76%, 3 studies) and 97% (87-99%, 3 studies) for 1 and 3 doses (insufficient data were identified to estimate 2-dose VE). Point estimates from 2 studies suggested VE>90% after 1 dose of the polyribosyl ribitol phosphate outer membrane protein vaccine, but meta-analysis was not possible. Using data from 4 cohort studies, 3-dose VE was estimated as 94% (88-97%). There was some evidence that Hib vaccine was less effective when administered with acellular (rather than whole cell) pertussis vaccine. Weak evidence from 2 studies suggested that a booster confers some additional protection following full primary vaccination and may compensate for an incomplete primary series. Observational data suggest that ≥2 doses of Hib vaccine are required for high effectiveness, but do not strongly favor any particular schedule.

Risk of bias and confounding of observational studies of Zika virus infection: A scoping review of research protocols.

PubMed

Reveiz, Ludovic; Haby, Michelle M; Martínez-Vega, Ruth; Pinzón-Flores, Carlos E; Elias, Vanessa; Smith, Emma; Pinart, Mariona; Broutet, Nathalie; Becerra-Posada, Francisco; Aldighieri, Sylvain; Van Kerkhove, Maria D

2017-01-01

Given the severity and impact of the current Zika virus (ZIKV) outbreak in the Americas, numerous countries have rushed to develop research studies to assess ZIKV and its potential health consequences. In an effort to ensure that studies are comprehensive, both internally and externally valid, and with reliable results, the World Health Organization, the Pan American Health Organization, Institut Pasteur, the networks of Fiocruz, the Consortia for the Standardization of Influenza Seroepidemiology (CONSISE) and the International Severe Acute Respiratory and Emerging Infection Consortium (ISARIC) have generated six standardized clinical and epidemiological research protocols and questionnaires to address key public health questions on ZIKV. We conducted a systematic search of ongoing study protocols related to ZIKV research. We analyzed the content of protocols of 32 cohort studies and 13 case control studies for systematic bias that could produce erroneous results. Additionally we aimed to characterize the risks of bias and confounding in observational studies related to ZIKV and to propose ways to minimize them, including the use of six newly standardized research protocols. Observational studies of ZIKV face an array of challenges, including measurement of exposure and outcomes (microcephaly and Guillain-Barré Syndrome). Potential confounders need to be measured where known and controlled for in the analysis. Selection bias due to non-random selection is a significant issue, particularly in the case-control design, and losses to follow-up is equally important for the cohort design. Observational research seeking to answer key questions on the ZIKV should consider these restrictions and take precautions to minimize bias in an effort to provide reliable and valid results. Utilization of the standardized research protocols developed by the WHO, PAHO, Institut Pasteur, and CONSISE will harmonize the key methodological aspects of each study design to minimize bias at different stages of the study. Biases need to be considered by researchers implementing the standardized protocols as well as by users of observational epidemiological studies of ZIKV.

Riceland mosquito management practices for Anopheles quadrimaculatus larvae.

PubMed

Allen, R A; Wilkes, W W; Lewis, C N; Meisch, M V

2008-12-01

Two separate but related studies were conducted regarding management of Anopheles quadrimaculatus larval populations in commercial rice fields near Cleveland, MS, in 2004. Study 1 was to evaluate the effectiveness of 2 treatments of aerially applied ultra-low volume applications of Bacillus thuringiensis var. israelensis (Bti) against An. quadrimaculatus larvae in dense, high-canopy mid- to late-season rice crop. Study 2 was to investigate the effect of preflood treatments of lambda-cyhalothrin (Karate), which is commonly used against rice water weevil (Lissorhoptrus oryzophilus), on An. quadrimaculatus larvae. Excellent initial, but short residual control (>99% control 1 day after treatment) was observed in the Bti-treated fields in both mid- and late-season rice. Little or no effect on mosquito larvae was observed in the lambda-cyhalothrin-treated fields. Results indicate that Bti can be effectively used by mosquito management personnel to control larval populations of An. quadrimaculatus in late-season rice fields; however, lambda-cyhalothrin did not effectively control larval An. quadrimaculatus when applied preflood to rice fields.

The influence of comorbidities on mortality in sarcoidosis: a observational prospective cohort study.

PubMed

Nowiński, Adam; Puścińska, Elzbieta; Goljan, Anna; Peradzynska, Joanna; Bednarek, Michal; Korzybski, Damian; Kamiński, Dariusz; Stokłosa, Anna; Czystowska, Monika; Śliwiński, Pawel; Górecka, Dorota

2017-09-01

The aim of this study was to identify the frequency and prevalence of comorbidities in sarcoid patients and to assess their influence on overall mortality in the cohort of patients with sarcoidosis. A cohort of 557 patients with histologically confirmed sarcoidosis diagnosed between 2007 and 2011 and a group of non-sarcoid controls were observed. All patients were carefully observed for comorbidities and mortality. 291 males (52.2%) and 266 females (47.8%) with mean age 48.4 ± 12.0 years in sarcoidosis group and a group of 100 controls with mean age (49.25 ± 10.3) were observed. The mean number of comorbidities in both groups was similar (0.9 ± 0.99 vs 0.81 ± 0.84 NS). The frequency of thyroid disease was significantly higher in sarcoidosis group comparing to controls at the time of diagnosis (OR = 3.62 P = 0.0144). During the observation period (median 58.0 months), 16 patients died (2.9%). The mean number of comorbidities was significantly higher in the groups of non-survivors as compared to survivors (2.8 ± 1.0, vs 0.8 ± 0.9), P < 0.0001. The comorbidity burden has strong impact on mortality in sarcoidosis. Thyroid diseases are more frequent in sarcoidosis than in non-sarcoid controls. © 2015 John Wiley & Sons Ltd.

Hierarchy of evidence: where observational studies fit in and why we need them.

PubMed

Hoppe, Daniel J; Schemitsch, Emil H; Morshed, Saam; Tornetta, Paul; Bhandari, Mohit

2009-05-01

Although randomized controlled designs are considered the so-called gold standard in medical trials and sit atop the hierarchy of evidence in evidence-based medicine, there are situations in which they are impractical or unethical to undertake, especially in surgical trials. Then, observational studies often provide the best source of information. In this paper, we use examples from the literature to explain the importance of observational studies in furthering the boundaries of orthopaedic surgery and knowledge of musculoskeletal disorders.

Self-Control and Emotional and Verbal Aggression in Dating Relationships: A Dyadic Understanding.

PubMed

Baker, Elizabeth A; Klipfel, Katherine M; van Dulmen, Manfred H M

2016-08-01

Guided by the dynamic developmental systems perspective, this study extends past research by examining the association between self-control and emotional and verbal aggression (EVA) using a dyadic multi-method design. Guided by empirical research and the dynamic developmental systems perspective, we hypothesized that (a) there would be a negative association between one's own self-control and one's own perpetration of EVA and (b) there would also be a negative association between one's partner's self-control and one's own perpetration of EVA. One hundred twenty heterosexual dating couples (ages 18-25 years) provided data on self-control (Grasmick et al.'s Low Self-Control Scale; reverse scored for ease of interpretation), self-reported perpetration of EVA (Emotional and Verbal Abuse subscale of the Conflict in Adolescent Dating Relationships Inventory), and observationally assessed perpetration of EVA. Data were analyzed using path analyses within the Actor-Partner Interdependence Model (APIM) framework. Consistent with previous findings, we found that self-control was negatively associated with the perpetration of EVA. Furthermore, we found partner effects, such that female-but not male-self-control predicted partner-observed perpetration of EVA. These findings highlight the importance of examining risk factors for EVA of both partners. Our findings also suggest that the association between self-control and EVA is partially a function of whether EVA is assessed through self-report or observational methodology. This highlights the need to conduct multi-method assessments in future research. As discussed in the article, our findings have implications for theories on intimate partner violence, study designs, and couple interventions.

New application of carbon nanotubes in haemostatic dressing filled with anticancer substance.

PubMed

Nowacki, M; Wiśniewski, M; Werengowska-Ciećwierz, K; Terzyk, A P; Kloskowski, T; Marszałek, A; Bodnar, M; Pokrywczyńska, M; Nazarewski, Ł; Pietkun, K; Jundziłł, A; Drewa, T

2015-02-01

The drug-carrier system used as innovative haemostatic dressing with oncostatic action is studied. It is obtained from CDDP (cisplatin) doped SWCNT (single walled carbon nanotubes), modified and purified by H2O2 in hydrothermal treatment process. In the in vivo nephron sparing surgery (NSS) study we used 35 BALB/c nude mice with induced renal cancer using adenocarcinoma 786-o cells. Animals were divided into four groups: CDDP(M-), CDDP(M+), CONTROL(M-) and CONTROL(M+). In CDDP(M-) and CDDP(M+) groups we used, intraoperatively, carbon nanotubes filled with cisplatin (CDDP). In CONTROL(M-) and CONTROL(M+) groups carbon nanotubes were used alone. During NSS free margin (M-) or positive margin (M+) was performed. In the CDDP(M-) group, we do not observe local tumor recurrences. In Group CDDP(M+) only one animal was diagnosed with tumor recurrence. In control groups the recurrent tumor formation was observed. In our study, it is shown that CDDP filled SWCNT inhibit cancer recurrence in animal model NSS study, and can be successfully applied as haemostatic dressings for local chemoprevention. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Handedness, immune disorders and information bias.

PubMed

Chavance, M; Dellatolas, G; Bousser, M G; Amor, B; Grardel, B; Kahan, A; Kahn, M F; Le Floch, J P; Tchobroutsky, G

1990-01-01

In order to investigate the relations between handedness and migraine or immune disorders, we performed a case control study comparing the handedness of patients suffering from systemic lupus erythematosus (SLE), type I diabetes, Graves' disease, or migraine to that of a random sample of controls from the general population. A handedness index was measured from a 10-item questionnaire. No significant difference was observed. But when the controls who denied having ever suffered from migraine or any allergic disease were set apart from those who gave at least one positive answer to the same questions, the former were found more right-handed, i.e. with a lower handedness index than the latter (P less than 0.05) and than the SLE patients (P less than 0.05). More generally, the mean observed handedness index of controls giving a positive answer to any question about their health was found repeatedly higher than that of controls giving a negative answer: this was observed for 27 of the 32 questions. These results are highly suggestive of an information bias, the subjects saying they use the right hand for each of the 10 activities considered in the questionnaire being more likely to deny having suffered from a given disease or used, more or less recently, some drug or medical service. Our conviction is that previous observations dealing with the same topic are also more easily explained by the presence of an information bias than by Geschwind's theory. The implications for the design of further epidemiologic studies are discussed.

Social support and glycemic control in type 2 diabetes: a systematic review of observational studies.

PubMed

Stopford, Rosanna; Winkley, Kirsty; Ismail, Khalida

2013-12-01

We aim to systematically review observational studies examining the association between social support and glycemic control in adults with type 2 diabetes. We searched MEDLINE, PsycINFO, EMBASE, Scopus, Web of Science and Sociological Abstracts to July 2012 for observational studies investigating the association between structural or functional aspects of social support (social networks, community ties, marital status, family support, perceived, actual, emotional or instrumental social support) and glycemic control (HbA1c). From electronic and reference searches, 29 studies were eligible. Twenty different assessments of social support were used. Family support and composite measures of support were most frequently associated with reduced HbA1c. There was no evidence for a beneficial effect of other support measures on HbA1c. We found marked variation in population, setting, measurement of social support and definition of outcome, limiting the methodological validity of research. Social support may be important in the management of type 2 diabetes, the need for consensus and standardization of measures is highlighted. The presence of informal support should be explored in routine diabetes care. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Range of control of cardiovascular variables by the hypothalamus

NASA Technical Reports Server (NTRS)

Smith, O. A.; Stephenson, R. B.; Randall, D. C.

1974-01-01

New methodologies were utilized to study the influence of the hypothalamus on the cardiovascular system. The regulation of myocardial activity was investigated in monkeys with hypothalamic lesions that eliminate cardiovascular responses. Observations showed that a specific part of the hypothalamus regulates changes in myocardial contractility that accompanies emotion. Studies of the hypothalamus control of renal blood flow showed the powerful potential control of this organ over renal circulation.

Histopathological observation of immunized rhesus macaques with plague vaccines after subcutaneous infection of Yersinia pestis.

PubMed

Tian, Guang; Qiu, Yefeng; Qi, Zhizhen; Wu, Xiaohong; Zhang, Qingwen; Bi, Yujing; Yang, Yonghai; Li, Yuchuan; Yang, Xiaoyan; Xin, Youquan; Li, Cunxiang; Cui, Baizhong; Wang, Zuyun; Wang, Hu; Yang, Ruifu; Wang, Xiaoyi

2011-04-29

In our previous study, complete protection was observed in Chinese-origin rhesus macaques immunized with SV1 (20 µg F1 and 10 µg rV270) and SV2 (200 µg F1 and 100 µg rV270) subunit vaccines and with EV76 live attenuated vaccine against subcutaneous challenge with 6×10(6) CFU of Y. pestis. In the present study, we investigated whether the vaccines can effectively protect immunized animals from any pathologic changes using histological and immunohistochemical techniques. In addition, the glomerular basement membranes (GBMs) of the immunized animals and control animals were checked by electron microscopy. The results show no signs of histopathological lesions in the lungs, livers, kidneys, lymph nodes, spleens and hearts of the immunized animals at Day 14 after the challenge, whereas pathological alterations were seen in the corresponding tissues of the control animals. Giemsa staining, ultrastructural examination, and immunohistochemical staining revealed bacteria in some of the organs of the control animals, whereas no bacterium was observed among the immunized animals. Ultrastructural observation revealed that no glomerular immune deposits on the GBM. These observations suggest that the vaccines can effectively protect animals from any pathologic changes and eliminate Y. pestis from the immunized animals. The control animals died from multi-organ lesions specifically caused by the Y. pestis infection. We also found that subcutaneous infection of animals with Y. pestis results in bubonic plague, followed by pneumonic and septicemic plagues. The histopathologic features of plague in rhesus macaques closely resemble those of rodent and human plagues. Thus, Chinese-origin rhesus macaques serve as useful models in studying Y. pestis pathogenesis, host response and the efficacy of new medical countermeasures against plague.

Physical control of interannual variations of the winter chlorophyll bloom in the northern Arabian Sea

NASA Astrophysics Data System (ADS)

Girijakumari Keerthi, Madhavan; Lengaigne, Matthieu; Levy, Marina; Vialard, Jerome; Parvathi, Vallivattathillam; de Boyer Montégut, Clément; Ethé, Christian; Aumont, Olivier; Suresh, Iyyappan; Parambil Akhil, Valiya; Moolayil Muraleedharan, Pillathu

2017-08-01

The northern Arabian Sea hosts a winter chlorophyll bloom, triggered by convective overturning in response to cold and dry northeasterly monsoon winds. Previous studies of interannual variations of this bloom only relied on a couple of years of data and reached no consensus on the associated processes. The current study aims at identifying these processes using both ˜ 10 years of observations (including remotely sensed chlorophyll data and physical parameters derived from Argo data) and a 20-year-long coupled biophysical ocean model simulation. Despite discrepancies in the estimated bloom amplitude, the six different remotely sensed chlorophyll products analysed in this study display a good phase agreement at seasonal and interannual timescales. The model and observations both indicate that the interannual winter bloom fluctuations are strongly tied to interannual mixed layer depth anomalies ( ˜ 0.6 to 0.7 correlation), which are themselves controlled by the net heat flux at the air-sea interface. Our modelling results suggest that the mixed layer depth control of the bloom amplitude ensues from the modulation of nutrient entrainment into the euphotic layer. In contrast, the model and observations both display insignificant correlations between the bloom amplitude and thermocline depth, which precludes a control of the bloom amplitude by daily dilution down to the thermocline depth, as suggested in a previous study.

Effects of motor imagery and action observation on hand grip strength, electromyographic activity and intramuscular oxygenation in the hand gripping gesture: A randomized controlled trial.

PubMed

Losana-Ferrer, Alejandro; Manzanas-López, Sergio; Cuenca-Martínez, Ferran; Paris-Alemany, Alba; La Touche, Roy

2018-04-01

The aim of this study was to evaluate the effects of motor imagery and action observation combined with a hand grip strength program on the forearm muscles. Sixty subjects were selected and randomized into three groups: motor imagery (n = 20), action observation (n = 20), or a control group (n = 20). Outcome measures included hand grip strength, electromyographical activity and intramuscular oxygenation. The hand grip strength significantly increased in the motor imagery (p < .001) and action observation (p < .001) groups compared with the control group, although there were no differences between the both groups (p = .30). In the electromyographical activity, intra-group significant differences were found in motor imagery (p = .002) and action observation (p = .003) groups, although there were no differences between the both groups (p = 1.00) Intramuscular oxygenation results did not show any statistically significant differences between any of the study groups (p > .05). Our results suggest that both motor imagery and action observation training, combined with a hand grip strength program, present a significant strength gain and significant change in the strength and electromyographical activity of the forearm muscles, however no change was found in intramuscular oxygenation. Copyright © 2018 Elsevier B.V. All rights reserved.

Clinical assessment of patients with recalcitrant psoriasis in a randomized, observer-blind, vehicle-controlled trial using indigo naturalis.

PubMed

Lin, Yin-Ku; Chang, Chee-Jen; Chang, Ya-Ching; Wong, Wen-Rou; Chang, Shu-Chen; Pang, Jong-Hwei Su

2008-11-01

To evaluate the efficacy and safety of treatment with indigo naturalis in patients with recalcitrant plaque-type psoriasis. Randomized, observer-blind, vehicle-controlled, intrapatient comparison study. Ambulatory department of a hospital. Forty-two outpatients with chronic plaque psoriasis were enrolled in the study from May 1, 2004, to April 30, 2005. The patients applied either indigo naturalis ointment or vehicle ointment topically to each of 2 bilaterally symmetrical psoriatic plaque lesions for 12 weeks (depending on the date of enrollment in the study). The outcomes were assessed using the following criteria: the sum of erythema, scaling, and induration scores and the clearing percentage of the target plaque lesion assessed by 2 blinded observers. Significant reductions in the sum of scaling, erythema, and induration scores (P < .001) (mean score, 6.3 after indigo naturalis treatment vs 12.8 in control subjects) and plaque area percentage (P < .001) (mean percentage, 38.5% after indigo naturalis treatment vs 90% in controls) were achieved with topical application of indigo naturalis ointment. Approximately 31 of 42 patients (74%) experienced clearance or near clearance of their psoriasis in the indigo ointment-treated lesion. Topical indigo naturalis ointment was a novel, safe, and effective therapy for plaque-type psoriasis.

Optical Verification of Microbubble Response to Acoustic Radiation Force in Large Vessels With In Vivo Results.

PubMed

Wang, Shiying; Wang, Claudia Y; Unnikrishnan, Sunil; Klibanov, Alexander L; Hossack, John A; Mauldin, F William

2015-11-01

The objective of this study was to optically verify the dynamic behaviors of adherent microbubbles in large blood vessel environments in response to a new ultrasound technique using modulated acoustic radiation force. Polydimethylsiloxane (PDMS) flow channels coated with streptavidin were used in targeted groups to mimic large blood vessels. The custom-modulated acoustic radiation force beam sequence was programmed on a Verasonics research scanner. In vitro experiments were performed by injecting a biotinylated lipid-perfluorobutane microbubble dispersion through flow channels. The dynamic response of adherent microbubbles was detected acoustically and simultaneously visualized using a video camera connected to a microscope. In vivo verification was performed in a large abdominal blood vessel of a murine model for inflammation with injection of biotinylated microbubbles conjugated with P-selectin antibody. Aggregates of adherent microbubbles were observed optically under the influence of acoustic radiation force. Large microbubble aggregates were observed solely in control groups without targeted adhesion. Additionally, the dispersion of microbubble aggregates were demonstrated to lead to a transient acoustic signal enhancement in control groups (a new phenomenon we refer to as "control peak"). In agreement with in vitro results, the control peak phenomenon was observed in vivo in a murine model. This study provides the first optical observation of microbubble-binding dynamics in large blood vessel environments with application of a modulated acoustic radiation force beam sequence. With targeted adhesion, secondary radiation forces were unable to produce large aggregates of adherent microbubbles. Additionally, the new phenomenon called control peak was observed both in vitro and in vivo in a murine model for the first time. The findings in this study provide us with a better understanding of microbubble behaviors in large blood vessel environments with application of acoustic radiation force and could potentially guide future beam sequence designs or signal processing routines for enhanced ultrasound molecular imaging.

Accelerated leukocyte telomere erosion in schizophrenia: Evidence from the present study and a meta-analysis.

PubMed

Rao, Shuquan; Kota, Lakshmi Narayanan; Li, Zongchang; Yao, Yao; Tang, Jinsong; Mao, Canquan; Jain, Sanjeev; Xu, Yong; Xu, Qi

2016-08-01

Human telomeres consist of tandem nucleotide repeats (TTAGGG) and associated proteins, and telomere length (TL) is reduced progressively with cell division over the lifespan. Telomere erosion might be accelerated or prevented to varying degrees when exposure to serious medical illnesses. In previous studies, an association between TL decrease and schizophrenia has been extensively reported; however, the results remain largely controversial. To further investigate TL in schizophrenia patients and reconcile this controversy, we first measured leucocyte TL (LTL) in our samples (52 paranoid schizophrenia, 89 non-paranoid patients and 120 controls), and then conducted a comprehensive meta-analysis of the existing results of LTL in patients of schizophrenia compared to healthy subjects. Totally, 11 studies encompassing 1243 patients of schizophrenia and 1274 controls were included in the final meta-analysis model. In our samples, significant reduction of LTL in paranoid schizophrenia was observed compared to controls (F = 50.88, P < 0.001); whereas there was no significant difference in LTL between non-paranoid schizophrenia and controls (F = 0.842, P = 0.360). For meta-analysis, random-effects model showed significant LTL decrease in patients of schizophrenia when compared to controls (Z = 2.07, P = 0.039, SMD = -0.48, 95% CI = -0.94 to -0.03). Moreover, a marginal decrease in LTL was observed in medicated patients (Z = 1.92, P = 0.055, SMD = -0.58, 95% CI = -1.18-0.01) and those patients with poor response to antipsychotics (Z = 1.76, P = 0.078, SMD = -0.60, 95% CI = -1.27-0.07). In conclusion, we observed significant reduction of LTL in individuals with schizophrenia compared with controls. However, all the studies included in the meta-analysis were cross-sectional, and better controlled long-term studies are needed to replicate this result. Copyright © 2016 Elsevier Ltd. All rights reserved.

Transcoronary sinus delivery of autologous bone marrow and angiogenesis in pig models with myocardial injury

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

Vicario, J.; Piva, J.; Pierini, A.

2002-06-01

Purpose: The aim of the investigation is to study myocardial injury on pig model with two objectives: (1) feasibility of stimulating angiogenesis with fresh autologous bone marrow; (2) administration of the same fresh autologous bone marrow via coronary sinus with transitory occlusion. Methods: A controlled study was done in animal model with three phases, in a study group of 12 pigs (bone marrow administration) as well as in control group of 4 pigs (saline administration). Phase 1--production of coronary stenosis and myocardial injury; Phase 2--two weeks later, administration of bone marrow through coronary sinus with 10 min occlusion in themore » study group and saline solution in the control group. Phase 3--two weeks later, histological staining with hematoxylin-eosin and inmunohistochemical staining with monoclonal antibody for smooth muscle {alpha}-actin were conducted on both study and control groups. Results: The percentage of angionenesis observed in the study group was 91% and 0% in control group. Counting of positive actin in affected and control areas showed statistically significant differences in relation to both groups: study group (1.37 vs. 0.79) and control group (0.47 vs. 0.51). The percentage of mononuclear immature cells observed in the myocardium in the study group was 25% and in the control group was 0%. There was no increment in the coronary collateral circulation when comparing coronary angiography. Conclusions: Autologous bone marrow in animal model with experimental myocardial injury enhances angiogenesis, as well as vessels with smooth muscles. The transitory occlusion of the coronary sinus might be an effective way to administer cells as those from the bone marrow.« less

Risk of Autism Spectrum Disorders in Children Born to Mothers With Rheumatoid Arthritis: A Systematic Literature Review.

PubMed

Wojcik, Sophie; Bernatsky, Sasha; Platt, Robert W; Pineau, Christian A; Clarke, Ann E; Fombonne, Éric; Bérard, Anick; Vinet, Évelyne

2017-12-01

There is recent evidence to suggest that in utero exposure to maternal antibodies and cytokines is an important risk factor for autism spectrum disorders (ASDs). We aimed to systematically review the risk of ASDs in children born to mothers with rheumatoid arthritis (RA) compared to children born to mothers without RA. We conducted a systematic review of original articles using the electronic databases PubMed, Embase, and Web of Science. Our literature search yielded a total of 70 articles. Of the potentially relevant studies retrieved, 67 were excluded for lack of relevance and/or because they did not report original data. Three studies were included in the final analysis. A case-control study found no difference in the prevalence of RA in mothers of children with ASDs versus control mothers. Another case-control study showed a statistically significant 8-fold increase in autoimmune disorders, including RA, in mothers of offspring with ASDs compared to controls. Forty-six percent of offspring with ASDs had a first-degree relative with RA, compared to 26% of controls. And in a population-based cohort study, investigators observed an increased risk of ASDs in children with a maternal history of RA compared to children born to unaffected mothers. These studies had methodologic limitations: none controlled for medication exposures, only 1 controlled for obstetric complications and considered the timing of RA diagnosis in relation to pregnancy, and all but 1 used a case-control study design. Observational studies suggest a potentially increased risk of ASDs in children born to mothers with RA compared to children born to mothers without RA, although data are limited. © 2017, American College of Rheumatology.

Dose and time-dependent sub-chronic toxicity study of hydroethanolic leaf extract of Flabellaria paniculata Cav. (Malpighiaceae) in rodents

PubMed Central

Akindele, Abidemi J.; Adeneye, Adejuwon A.; Salau, Oluwole S.; Sofidiya, Margaret O.; Benebo, Adokiye S.

2014-01-01

Flabellaria paniculata Cav. (Malpighiaceae) is a climbing shrub, the preparations of which are used in the treatment of wounds and ulcers in Nigeria and Ghana. This study investigated the sub-chronic toxicity profile of the hydroethanolic leaf extract of F. paniculata (HLE-FP). HLE-FP was administered p.o. (20, 100, and 500 mg/kg) for 30 and 60 days to different groups of rats. Control animals received 10 ml/kg distilled water. In the group of animals for reversibility study, HLE-FP administration ceased on the 60th day and animals were monitored for a further 15 days. Results showed that oral treatment with HLE-FP for 30 days caused significant (p < 0.05) reductions in weight gain pattern compared to control. These changes were sustained with 60 days treatment. However, no significant (p > 0.05) differences in relative organ weights between control and treatment groups were observed. HLE-FP-treated rats showed significant (p < 0.05) increases in Hb, PCV and RBC on day 30 and significant (p < 0.05) increases in MCV and MCH indices on day 60 compared to control. There were significant (p < 0.05) elevations in serum K+, urea and creatinine compared to control. The liver function tests showed slight but non-significant alterations in relevant parameters when compared to control. Biochemical findings were supported by histopathological observations of vital organs including the kidney and liver. Toxicities observed in respect of kidney function were irreversible at 15 days of stoppage of treatment. In the acute toxicity study, HLE-FP given p.o. caused no lethality at 5000 mg/kg but behavioral manifestations like restlessness, generalized body tremor, feed, and water refusal were observed. The i.p. LD50 was estimated to be 2951.2 mg/kg. Findings in this study showed that HLE-FP is relatively non-toxic on acute exposure and generally safe on sub-chronic administration, but could be deleterious on the kidneys on prolonged oral exposure at a high dose. Thus, caution should be exercised with its long-term usage. PMID:24795634

Comparison between treatment effects in a randomised controlled trial and an observational study using propensity scores in primary care.

PubMed

Stuart, Beth L; Grebel, Louise En; Butler, Christopher C; Hood, Kerenza; Verheij, Theo J M; Little, Paul

2017-09-01

Although randomised controlled trials (RCTs) are considered 'gold standard' evidence, they are not always feasible or appropriate, and may represent a select population. Observational studies provide a useful alternative to enhance applicability, but results can be biased due to confounding. To explore the utility of propensity scores for causal inference in an observational study. Comparison of the effect of amoxicillin on key outcomes in an international RCT and observational study of lower respiratory tract infections. Propensity scores were calculated and applied as probability weights in the analyses. The adjusted results were compared with the effects reported in the RCT. Groups were well balanced in the RCT but significantly imbalanced in the observational study, with evidence of confounding by indication: patients receiving antibiotics tended to be older and more unwell at baseline consultation. In the trial duration of symptoms (hazard ratio 1.06, 95% CI = 0.96 to 1.18) and symptom severity (-0.07, 95% CI = -0.15 to 0.007) did not differ between groups. Weighting by propensity score in the observational study resulted in very similar estimates of effect: duration of symptoms (hazard ratio 1.06, 95% CI = 0.80 to 1.40) and difference for symptom severity (-0.07, 95% CI = -0.34 to 0.20). The observational study, after conditioning on propensity score, echoed the trial results. Provided that detailed information is available on potential sources of confounding, effects of interventions can probably be assessed reasonably well in observational datasets, allowing them to be more directly compared with the results of RCTs. © British Journal of General Practice 2017.

The impact of vitamin D in pregnancy on extraskeletal health in children: a systematic review.

PubMed

Christesen, Henrik T; Elvander, Claes; Lamont, Ronald F; Jørgensen, Jan S

2012-12-01

The impact of maternal vitamin D status in pregnancy on the extraskeletal health of the offspring has become a "hot topic" with a potential for cost-beneficial prevention. The objective of this study was to systematically review the level I and II evidence. PubMed, Embase and Cochrane databases were searched using the MeSH terms "vitamin D" AND "pregnancy" until 1 January 2012. The search was limited to randomized controlled trials (evidence level I) and observational studies (evidence level II) in humans and in the English language. Papers reporting on vitamin D supplementation in combination with other supplements, or not reporting on 25OHD or outcomes of the offspring were excluded. Six randomized controlled trials and 24 observational studies were finally included. In randomized controlled studies, vitamin D supplementation resulted in increased birthweight in one study, but showed no effect in five other studies. In cohort and case-control studies, higher vitamin D intake, or higher 25OHD, was associated with increased birthweight in large studies only, and modified by vitamin D receptor polymorphisms and by race (U-shaped in Caucasians in one unconfirmed study). The risks of HIV mother-to-child transmission, rhinitis symptoms and eczema were lower. Data were conflicting on the effect on respiratory infections and wheezing, whereas U-shaped associations to inhalant allergen-specific IgE at five years and to schizophrenia were reported in unconfirmed studies. The risk of type 1 diabetes at 15 years was lower or unchanged. It is concluded that observational studies suggest an effect of vitamin D on several outcomes. U-Shaped associations warrant caution. © 2012 The Authors Acta Obstetricia et Gynecologica Scandinavica© 2012 Nordic Federation of Societies of Obstetrics and Gynecology.

Steroidal contraceptives and bone fractures in women: evidence from observational studies.

PubMed

Lopez, Laureen M; Chen, Mario; Mullins Long, Sarah; Curtis, Kathryn M; Helmerhorst, Frans M

2015-07-21

Age-related decline in bone mass increases the risk of skeletal fractures, especially those of the hip, spine, and wrist. Steroidal contraceptives have been associated with changes in bone mineral density in women. Whether such changes affect the risk of fractures later in life is unclear. Hormonal contraceptives are among the most effective and most widely-used contraceptives. Concern about fractures may limit the use of these effective contraceptives. Observational studies can collect data on premenopausal contraceptive use as well as fracture incidence later in life. We systematically reviewed the evidence from observational studies of hormonal contraceptive use for contraception and the risk of fracture in women. Through June 2015, we searched for observational studies. The databases included PubMed, POPLINE, Cochrane Central Register of Controlled Trials (CENTRAL), LILACS, EMBASE, CINAHL, and Web of Science. We also searched for recent clinical trials through ClinicalTrials.gov and the ICTRP. For other studies, we examined reference lists of relevant articles and wrote to investigators for additional reports. We included cohort and case-control studies of hormonal contraceptive use. Interventions included comparisons of a hormonal contraceptive with a non-hormonal contraceptive, no contraceptive, or another hormonal contraceptive. The primary outcome was the risk of fracture. Two authors independently extracted the data. One author entered the data into RevMan, and a second author verified accuracy. We examined the quality of evidence using the Newcastle-Ottawa Quality Assessment Scale (NOS), developed for case-control and cohort studies. Sensitivity analysis included studies of moderate or high quality based on our assessment with the NOS.Given the need to control for confounding factors in observational studies, we used adjusted estimates from the models as reported by the authors. Where we did not have adjusted analyses, we calculated the odds ratio (OR) with 95% confidence interval (CI). Due to varied study designs, we did not conduct meta-analysis. We included 14 studies (7 case-control and 7 cohort studies). These examined oral contraceptives (OCs), depot medroxyprogesterone acetate (DMPA), and the hormonal intrauterine device (IUD). This section focuses on the sensitivity analysis with six studies that provided moderate or high quality evidence.All six studies examined oral contraceptive use. We noted few associations with fracture risk. One cohort study reported OC ever-users had increased risk for all fractures (RR 1.20, 95% CI 1.08 to 1.34). However, a case-control study with later data from a subset reported no association except for those with 10 years or more since use (OR 1.55, 95% CI 1.03 to 2.33). Another case-control study reported increased risk only for those who had 10 or more prescriptions (OR 1.09, 95% CI 1.03 to 1.16). A cohort study of postmenopausal women found no increased fracture risk for OC use after excluding women with prior fracture. Two other studies found little evidence of association between OC use and fracture risk. A cohort study noted increased risk for subgroups, such as those with longer use or specific intervals since use. A case-control study reported increased risk for any fracture only among young women with less than average use.Two case-control studies also examined progestin-only contraceptives. One reported increased fracture risk for DMPA ever-use (OR 1.44, 95% CI 1.01 to 2.06), more than four years of use (OR 2.16, 95% CI 1.32 to 3.53), and women over 50 years old. The other reported increased risk for any past use, including one or two prescriptions (OR 1.17, 95% CI 1.07 to 1.29) and for current use of 3 to 9 prescriptions (OR 1.36, 95% CI 1.15 to 1.60) or 10 or more (OR 1.54, 95% CI 1.33 to 1.78). For the levonorgestrel-releasing IUD, one study reported reduced fracture risk for ever-use (OR 0.75, 95% CI 0.64 to 0.87) and for longer use. Observational studies do not indicate an overall association between oral contraceptive use and fracture risk. Some reported increased risk for specific user subgroups. DMPA users may have an increased fracture risk. One study indicated hormonal IUD use may be associated with decreased risk. Observational studies need adjusted analysis because the comparison groups usually differ. Investigators should be clear about the variables examined in multivariate analysis.

Switched-Observer-Based Adaptive Neural Control of MIMO Switched Nonlinear Systems With Unknown Control Gains.

PubMed

Long, Lijun; Zhao, Jun

2017-07-01

In this paper, the problem of adaptive neural output-feedback control is addressed for a class of multi-input multioutput (MIMO) switched uncertain nonlinear systems with unknown control gains. Neural networks (NNs) are used to approximate unknown nonlinear functions. In order to avoid the conservativeness caused by adoption of a common observer for all subsystems, an MIMO NN switched observer is designed to estimate unmeasurable states. A new switched observer-based adaptive neural control technique for the problem studied is then provided by exploiting the classical average dwell time (ADT) method and the backstepping method and the Nussbaum gain technique. It effectively handles the obstacle about the coexistence of multiple Nussbaum-type function terms, and improves the classical ADT method, since the exponential decline property of Lyapunov functions for individual subsystems is no longer satisfied. It is shown that the technique proposed is able to guarantee semiglobal uniformly ultimately boundedness of all the signals in the closed-loop system under a class of switching signals with ADT, and the tracking errors converge to a small neighborhood of the origin. The effectiveness of the approach proposed is illustrated by its application to a two inverted pendulum system.

Cautionary tales in the interpretation of observational studies of effects of clinical interventions.

PubMed

Scott, I A; Attia, J

2017-02-01

Observational studies of the effectiveness of clinical interventions are proliferating as more 'real-world' clinical data (so called 'big data') are gathered from clinical registries, administrative datasets and electronic health records. While well-conducted randomised controlled trials (RCT) remain the scientific standard in assessing the efficacy of clinical interventions, well-designed observational studies may add to the evidence base of effectiveness in situations where RCT are of limited value or very difficult to perform. Rather than dismissing observational studies, we need to determine what circumstances may justify doing an observational study and when the study is sufficiently rigorous to be considered reasonably trustworthy. This article proposes criteria by which users of the literature might make such determinations. © 2016 Royal Australasian College of Physicians.

Gender-Differentiated Parenting Revisited: Meta-Analysis Reveals Very Few Differences in Parental Control of Boys and Girls.

PubMed

Endendijk, Joyce J; Groeneveld, Marleen G; Bakermans-Kranenburg, Marian J; Mesman, Judi

2016-01-01

Although various theories describe mechanisms leading to differential parenting of boys and girls, there is no consensus about the extent to which parents do treat their sons and daughters differently. The last meta-analyses on the subject were conducted more than fifteen years ago, and changes in gender-specific child rearing in the past decade are quite plausible. In the current set of meta-analyses, based on 126 observational studies (15,034 families), we examined mothers' and fathers' differential use of autonomy-supportive and controlling strategies with boys and girls, and the role of moderators related to the decade in which the study was conducted, the observational context, and sample characteristics. Databases of Web of Science, ERIC, PsychInfo, Online Contents, Picarta, and Proquest were searched for studies examining differences in observed parental control of boys and girls between the ages of 0 and 18 years. Few differences were found in parents' use of control with boys and girls. Parents were slightly more controlling with boys than with girls, but the effect size was negligible (d = 0.08). The effect was larger, but still small, in normative groups and in samples with younger children. No overall effect for gender-differentiated autonomy-supportive strategies was found (d = 0.03). A significant effect of time emerged: studies published in the 1970s and 1980s reported more autonomy-supportive strategies with boys than toward girls, but from 1990 onwards parents showed somewhat more autonomy-supportive strategies with girls than toward boys. Taking into account parents' gender stereotypes might uncover subgroups of families where gender-differentiated control is salient, but based on our systematic review of the currently available large data base we conclude that in general the differences between parenting of boys versus girls are minimal.

The effect of plant sterols on serum triglyceride concentrations is dependent on baseline concentrations: a pooled analysis of 12 randomised controlled trials.

PubMed

Demonty, Isabelle; Ras, Rouyanne T; van der Knaap, Henk C M; Meijer, Linsie; Zock, Peter L; Geleijnse, Johanna M; Trautwein, Elke A

2013-02-01

Plant sterols (PS) are well known for their low-density lipoprotein cholesterol-lowering effect. Until recently, they were believed to have little or no impact on blood triglycerides (TG). However, studies taken individually were possibly lacking statistical power to detect modest TG decreases. This study was performed to quantify the TG-lowering effect of PS by pooling individual subject data from 12 randomised controlled trials that investigated the effects of PS on blood lipids. The main outcome variable was the control-adjusted PS effect on relative (%) and absolute (mmol/L) changes in TG. The relative and absolute changes in high-density lipoprotein cholesterol (HDL-C) were also assessed. Differences in changes of serum lipid concentrations between PS and control treatments were estimated by an ANCOVA using a random effect model which included PS intake (active or control), study and predefined subject characteristics. The twelve randomised controlled trials included in total 935 hypercholesterolaemic subjects not preselected based on their baseline TG concentrations. In most studies, the PS dose ranged between 1.6 and 2.5 g/day. PS intake significantly lowered serum TG by 6.0% (95% CI: -10.7, -1.2) or 0.12 mmol/L (95% CI: -0.20, -0.04). No significant interaction was observed between PS intake and baseline TG concentrations on relative changes, but, on absolute changes, interaction was significant with larger TG decreases observed with higher TG concentrations at baseline. No effects were observed on HDL-C concentrations. These results show that PS exert a modest TG-lowering effect which is dependent on baseline concentrations.

Media Coverage of Medical Journals: Do the Best Articles Make the News?

PubMed Central

Selvaraj, Senthil; Borkar, Durga S.; Prasad, Vinay

2014-01-01

Background News coverage of medical research is followed closely by many Americans and affects the practice of medicine and influence of scientific research. Prior work has examined the quality of media coverage, but no investigation has characterized the choice of stories covered in a controlled manner. We examined whether the media systematically covers stories of weaker study design. Methods We compared study characteristics of 75 clinically-oriented journal articles that received coverage in the top five newspapers by circulation against 75 clinically-oriented journal articles that appeared in the top five medical journals by impact factor over a similar timespan. Subgroup analysis was performed to determine whether differences between investigations from both sources varied by study type (randomized controlled trial [RCT] or observational study). Results Investigations receiving coverage from newspapers were less likely to be RCTs (17% vs. 35%, p = 0.016) and more likely to be observational studies (75% vs. 47%, p<0.001). No difference was observed in number of people studied (median: 1034 vs. 1901, p = 0.14) or length of follow-up (median: 1.80 vs. 1.00 years, p = 0.22). In subgroup analysis, observational studies from the media used smaller sample sizes (median: 1984 vs. 21136, p = 0.029) and were more likely to be cross-sectional (71% vs. 31%, p<0.001), while no differences were observed for RCTs. Conclusions Newspapers were more likely to cover observational studies and less likely to cover RCTs than high impact journals. Additionally, when the media does cover observational studies, they select articles of inferior quality. Newspapers preferentially cover medical research with weaker methodology. PMID:24465543

Observational Study Designs for Comparative Effectiveness Research: An Alternative Approach to Close Evidence Gaps in Head-and-Neck Cancer

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

Goulart, Bernardo H.L., E-mail: bhg@uw.edu; University of Washington, Seattle, Washington; Ramsey, Scott D.

Comparative effectiveness research (CER) has emerged as an approach to improve quality of care and patient outcomes while reducing healthcare costs by providing evidence to guide healthcare decisions. Randomized controlled trials (RCTs) have represented the ideal study design to support treatment decisions in head-and-neck (H and N) cancers. In RCTs, formal chance (randomization) determines treatment allocation, which prevents selection bias from distorting the measure of treatment effects. Despite this advantage, only a minority of patients qualify for inclusion in H and N RCTs, which limits the validity of their results to the broader H and N cancer patient population seenmore » in clinical practice. Randomized controlled trials often do not address other knowledge gaps in the management of H and N cancer, including treatment comparisons for rare types of H and N cancers, monitoring of rare or late toxicity events (eg, osteoradionecrosis), or in some instances an RCT is simply not feasible. Observational studies, or studies in which treatment allocation occurs independently of investigators' choice or randomization, may address several of these gaps in knowledge, thereby complementing the role of RCTs. This critical review discusses how observational CER studies complement RCTs in generating the evidence to inform healthcare decisions and improve the quality of care and outcomes of H and N cancer patients. Review topics include a balanced discussion about the strengths and limitations of both RCT and observational CER study designs; a brief description of design and analytic techniques to handle selection bias in observational studies; examples of observational studies that inform current clinical practices and management of H and N cancers; and suggestions for relevant CER questions that could be addressed by an observational study design.« less

Observational study designs for comparative effectiveness research: an alternative approach to close evidence gaps in head-and-neck cancer.

PubMed

Goulart, Bernardo H L; Ramsey, Scott D; Parvathaneni, Upendra

2014-01-01

Comparative effectiveness research (CER) has emerged as an approach to improve quality of care and patient outcomes while reducing healthcare costs by providing evidence to guide healthcare decisions. Randomized controlled trials (RCTs) have represented the ideal study design to support treatment decisions in head-and-neck (H&N) cancers. In RCTs, formal chance (randomization) determines treatment allocation, which prevents selection bias from distorting the measure of treatment effects. Despite this advantage, only a minority of patients qualify for inclusion in H&N RCTs, which limits the validity of their results to the broader H&N cancer patient population seen in clinical practice. Randomized controlled trials often do not address other knowledge gaps in the management of H&N cancer, including treatment comparisons for rare types of H&N cancers, monitoring of rare or late toxicity events (eg, osteoradionecrosis), or in some instances an RCT is simply not feasible. Observational studies, or studies in which treatment allocation occurs independently of investigators' choice or randomization, may address several of these gaps in knowledge, thereby complementing the role of RCTs. This critical review discusses how observational CER studies complement RCTs in generating the evidence to inform healthcare decisions and improve the quality of care and outcomes of H&N cancer patients. Review topics include a balanced discussion about the strengths and limitations of both RCT and observational CER study designs; a brief description of design and analytic techniques to handle selection bias in observational studies; examples of observational studies that inform current clinical practices and management of H&N cancers; and suggestions for relevant CER questions that could be addressed by an observational study design. Copyright © 2014 Elsevier Inc. All rights reserved.

Uric acid in aortic dissection: A meta-analysis.

PubMed

Li, Xiaodong; Jiang, Shanshan; He, Jiaan; Li, Nan; Fan, Yichuan; Zhao, Xingzhi; Hu, Xinhua

2018-06-04

Studies on the serum uric acid levels in patients with aortic dissection have yielded conflicting results. To compare the difference in serum uric acid (SUA) levels between aortic dissection patients and controls by meta-analysis. Electronic literature search was conducted in PubMed, Embase, CKNI, CBM, Wanfang, and VIP databases until January 31, 2018. All observational studies that investigated SUA levels in aortic dissection patients and controls were included. Weighted mean difference (WMD) with 95% confidence intervals (CI) was used to summarize the difference in SUA levels between aortic dissection and control group. A total of seven case-control studies involving 1197 patients and 1193 controls were included. Pooled analysis showed that SUA levels were significantly higher in aortic dissection patients compared with those in the controls (WMD 58.22 μmol/L; 95% CI 26.71-89.73) in a random effect model. No significant difference (WMD 9.94 μmol/L; 95% CI -17.89-37.76) was observed in SUA levels between Stanford type A and Stanford type B aortic dissection. This meta-analysis provides evidence that SUA levels are significantly higher among patients with aortic dissection than those in controls. Elevated SUA levels may contribute to the pathogenesis of aortic dissection. Further large clinical studies to investigate whether SUA levels are an independently risk factor for aortic dissection are warranted. Copyright © 2018 Elsevier B.V. All rights reserved.

Flexible Modes Control Using Sliding Mode Observers: Application to Ares I

NASA Technical Reports Server (NTRS)

Shtessel, Yuri B.; Hall, Charles E.; Baev, Simon; Orr, Jeb S.

2010-01-01

The launch vehicle dynamics affected by bending and sloshing modes are considered. Attitude measurement data that are corrupted by flexible modes could yield instability of the vehicle dynamics. Flexible body and sloshing modes are reconstructed by sliding mode observers. The resultant estimates are used to remove the undesirable dynamics from the measurements, and the direct effects of sloshing and bending modes on the launch vehicle are compensated by means of a controller that is designed without taking the bending and sloshing modes into account. A linearized mathematical model of Ares I launch vehicle was derived based on FRACTAL, a linear model developed by NASA/MSFC. The compensated vehicle dynamics with a simple PID controller were studied for the launch vehicle model that included two bending modes, two slosh modes and actuator dynamics. A simulation study demonstrated stable and accurate performance of the flight control system with the augmented simple PID controller without the use of traditional linear bending filters.

Poor hospital infection control practice in hand hygiene, glove utilization, and usage of tourniquets.

PubMed

Sacar, Suzan; Turgut, Huseyin; Kaleli, Ilknur; Cevahir, Nural; Asan, Ali; Sacar, Mustafa; Tekin, Koray

2006-11-01

Hospital-acquired infection often occurs because of lapses in accepted standards of practice on the part of health care personnel. The aim of this study is to attract attention on poor hospital infection control practice in venepuncture and use of tourniquets and emphasize the importance of hand hygiene. Overall compliance with hygiene during usage of tourniquets and routine patient care before and after implementation of a hospital infection control measures was evaluated. According to the questionnaire, only 26.9% of respondents always washed their hands both before and after venepuncture. In the second step of the study, based on direct observation, hands were washed both before and after venepuncture on only 41 (45.1%) occasions. Failure to remove gloves after patient contact was observed on 23.1% occasions. Our survey reveals poor infection control practice in hand hygiene, glove utilization, and usage of tourniquets and the implementation of infection control measures produced a moderate improvement in compliance with them.

Control concepts for the alleviation of windshears and gusts

NASA Technical Reports Server (NTRS)

Rynaski, E. G.; Govindaraj, K. S.

1982-01-01

Automatic control system design methods for gust and shear alleviation were studied. It is shown that automatic gust/shear alleviation systems can be quite effective if both throttle and elevator are used in harmony to produce the forces and moments required to counter the effects of the windshear. Regulation with respect to ground speed or airspeed results in very similar system designs. The application of the NASA total energy probe in the detection of windshear and criteria for alleviation is considered. The theory and application of robust output observers is extended. Design examples show how implementation of the control laws can be accomplished using observers, and thereby resulting in less complex control system configurations.

Controller design approach based on linear programming.

PubMed

Tanaka, Ryo; Shibasaki, Hiroki; Ogawa, Hiromitsu; Murakami, Takahiro; Ishida, Yoshihisa

2013-11-01

This study explains and demonstrates the design method for a control system with a load disturbance observer. Observer gains are determined by linear programming (LP) in terms of the Routh-Hurwitz stability criterion and the final-value theorem. In addition, the control model has a feedback structure, and feedback gains are determined to be the linear quadratic regulator. The simulation results confirmed that compared with the conventional method, the output estimated by our proposed method converges to a reference input faster when a load disturbance is added to a control system. In addition, we also confirmed the effectiveness of the proposed method by performing an experiment with a DC motor. © 2013 ISA. Published by ISA. All rights reserved.

Output-Feedback Model Predictive Control of a Pasteurization Pilot Plant based on an LPV model

NASA Astrophysics Data System (ADS)

Karimi Pour, Fatemeh; Ocampo-Martinez, Carlos; Puig, Vicenç

2017-01-01

This paper presents a model predictive control (MPC) of a pasteurization pilot plant based on an LPV model. Since not all the states are measured, an observer is also designed, which allows implementing an output-feedback MPC scheme. However, the model of the plant is not completely observable when augmented with the disturbance models. In order to solve this problem, the following strategies are used: (i) the whole system is decoupled into two subsystems, (ii) an inner state-feedback controller is implemented into the MPC control scheme. A real-time example based on the pasteurization pilot plant is simulated as a case study for testing the behavior of the approaches.

Diabetes Control among Vietnamese Patients in Ho Chi Minh City: An Observational Cross-Sectional Study

ERIC Educational Resources Information Center

Yokokawa, Hirohide; Khue, Nguyen Thy; Goto, Aya; Nam, Tran Quang; Trung, Tran The; Khoa, Vo Tuan; Ngoc, Nguyen Thi Boi; Minh, Pham Nghiem; Vinh, Nguyen Quang; Okayama, Akira; Yasumura, Seiji

2010-01-01

The objective of this study was to assess the extent of diabetic control and its associated factors among Vietnamese patients with diabetes mellitus (DM). The study was conducted among 652 outpatients who were recruited at a public general hospital (People Hospital 115) and a private clinic (Medic Center) in Ho Chi Minh City, Vietnam. Median age…

Health risks of employees working in pesticide retail shops: An exploratory study.

PubMed

Kesavachandran, C; Pathak, M K; Fareed, M; Bihari, V; Mathur, N; Srivastava, A K

2009-12-01

Shop keepers dealing with pesticides are exposed to multiple pesticides that include organophosphates, organochlorines, carbamates, pyrethroids. Hence an exploratory health study was conducted on shopkeepers selling pesticides in urban areas of Lucknow and Barabanki District, Uttar Pradesh, India. Detailed information regarding socio-economic status, family history, personal habits and work practices were recorded for 20 subjects and controls by the investigator on a pre-tested questionnaire. Clinical examination including neurological studies of the shopkeepers and control subjects was done. The study revealed significant slowing of motor nerve conduction velocity and low peak expiratory flow rate among shopkeepers as compared to control subjects. Prevalence of significantly higher gastro-intestinal problems was also observed among exposed subjects. Neurological, ocular, cardiovascular and musculo-skeletal symptoms were also found to be higher among shopkeepers. This was not statistically significant. Significantly higher relative risk for sickness related to systems viz., cardio-vasular, genito-urinary, respiratory, nervous and dermal was observed among exposed subjects compared to controls. These findings provide a prima facie evidence of clinical manifestations because of multiple exposures to pesticides and poor safety culture at work place.

Cardiac peroxisome proliferator-activated receptor-γ expression is modulated by oxidative stress in acutely infrasound-exposed cardiomyocytes.

PubMed

Pei, Zhaohui; Meng, Rongsen; Zhuang, Zhiqiang; Zhao, Yiqiao; Liu, Fangpeng; Zhu, Miao-Zhang; Li, Ruiman

2013-12-01

The aim of the present study was to examine the effects of acute infrasound exposure on oxidative damage and investigate the underlying mechanisms in rat cardiomyocytes. Neonatal rat cardiomyocytes were cultured and exposed to infrasound for several days. In the study, the expression of CAT, GPx, SOD1, and SOD2 and their activities in rat cardiomyocytes in infrasound exposure groups were significantly decreased compared to those in the various time controls, along with significantly higher levels of O2 (-) and H2O2. Decreased cardiac cell viability was not observed in various time controls. A significant reduction in cardiac cell viability was observed in the infrasound group compared to the control, while significantly increased cardiac cell viability was observed in the infrasound exposure and rosiglitazone pretreatment group. Compared to the control, rosiglitazone significantly upregulated CAT, GPx, SOD1, and SOD2 expression and their activities in rat cardiomyocytes exposed to infrasound, while the levels of O2 (-) or H2O2 were significantly decreased. A potential link between a significant downregulation of PPAR-γ expression in rat cardiomyocytes in the infrasound group was compared to the control and infrasound-induced oxidative stress. These findings indicate that infrasound can induce oxidative damage in rat cardiomyocytes by inactivating PPAR-γ.

Inter- and intra-observer reliability of clinical movement-control tests for marines

PubMed Central

2012-01-01

Background Musculoskeletal disorders particularly in the back and lower extremities are common among marines. Here, movement-control tests are considered clinically useful for screening and follow-up evaluation. However, few studies have addressed the reliability of clinical tests, and no such published data exists for marines. The present aim was therefore to determine the inter- and intra-observer reliability of clinically convenient tests emphasizing movement control of the back and hip among marines. A secondary aim was to investigate the sensitivity and specificity of these clinical tests for discriminating musculoskeletal pain disorders in this group of military personnel. Methods This inter- and intra-observer reliability study used a test-retest approach with six standardized clinical tests focusing on movement control for back and hip. Thirty-three marines (age 28.7 yrs, SD 5.9) on active duty volunteered and were recruited. They followed an in-vivo observation test procedure that covered both low- and high-load (threshold) tasks relevant for marines on operational duty. Two independent observers simultaneously rated performance as “correct” or “incorrect” following a standardized assessment protocol. Re-testing followed 7–10 days thereafter. Reliability was analysed using kappa (κ) coefficients, while discriminative power of the best-fitting tests for back- and lower-extremity pain was assessed using a multiple-variable regression model. Results Inter-observer reliability for the six tests was moderate to almost perfect with κ-coefficients ranging between 0.56-0.95. Three tests reached almost perfect inter-observer reliability with mean κ-coefficients > 0.81. However, intra-observer reliability was fair-to-moderate with mean κ-coefficients between 0.22-0.58. Three tests achieved moderate intra-observer reliability with κ-coefficients > 0.41. Combinations of one low- and one high-threshold test best discriminated prior back pain, but results were inconsistent for lower-extremity pain. Conclusions Our results suggest that clinical tests of movement control of back and hip are reliable for use in screening protocols using several observers with marines. However, test-retest reproducibility was less accurate, which should be considered in follow-up evaluations. The results also indicate that combinations of low- and high-threshold tests have discriminative validity for prior back pain, but were inconclusive for lower-extremity pain. PMID:23273285

FABRICA: A Bioreactor Platform for Printing, Perfusing, Observing, & Stimulating 3D Tissues.

PubMed

Smith, Lester J; Li, Ping; Holland, Mark R; Ekser, Burcin

2018-05-15

We are introducing the FABRICA, a bioprinter-agnostic 3D-printed bioreactor platform designed for 3D-bioprinted tissue construct culture, perfusion, observation, and analysis. The computer-designed FABRICA was 3D-printed with biocompatible material and used for two studies: (1) Flow Profile Study: perfused 5 different media through a synthetic 3D-bioprinted construct and ultrasonically analyzed the flow profile at increasing volumetric flow rates (VFR); (2) Construct Perfusion Study: perfused a 3D-bioprinted tissue construct for a week and compared histologically with a non-perfused control. For the flow profile study, construct VFR increased with increasing pump VFR. Water and other media increased VFR significantly while human and pig blood showed shallow increases. For the construct perfusion study, we confirmed more viable cells in perfused 3D-bioprinted tissue compared to control. The FABRICA can be used to visualize constructs during 3D-bioprinting, incubation, and to control and ultrasonically analyze perfusion, aseptically in real-time, making the FABRICA tunable for different tissues.

Modified directly observed treatment for tuberculosis versus self-administered therapy: an observational study in rural Greece.

PubMed

Charokopos, N; Tsiros, G; Foka, A; Voila, P; Chrysanthopoulos, K; Spiliopoulou, I; Jelastopulu, E

2013-01-01

Directly Observed Treatment (DOT) is the key element of DOTS (directly observed treatment, short course), part of the internationally recommended control strategy for tuberculosis (TB). The evaluation of DOT has not been widely evaluated in rural areas in developed settings. The aim of this pilot study was to evaluate a modified DOT program (MDOT) by a general practitioner (GP) in a rural area of southwest Greece, where there is substantial underreporting of TB cases. Thirteen new TB cases with 30 close contacts were compared with 41 past-treated TB subjects (controls) with 111 close contacts in this observational, case-control study. Home visits by a GP were conducted and comparison of various data (laboratory findings, treatment outcomes, questionnaire-based parameters, on-site recorded conditions) was performed in both newly detected pulmonary TB cases and previously treated TB cases managed without DOT intervention. MDOT by GP implementation revealed that 11 cases (84.6%) were successfully treated, one (7.7%) case died, and one (7.7%) was lost to follow up. None of the close contacts of new TB cases was infected with active TB, while 6.3% of previously-treated TB subjects were infected with active TB and had to receive a complete anti-TB regimen. Chemoprophylaxis was administered to 13.3% of close contacts of new cases; whereas 12.6% of close contacts of previously-treated patients received chemoprophylaxis. This pilot study revealed that a GP is able to implement a program based on DOT resulting in high treatment adherence and prevention of TB compared with the conventional self-administration of treatment.

Dermatoglyphic patterns in dementia of the Alzheimer type: a case-control study.

PubMed

Berr, C; Okra-Podrabinek, N; Feteanu, D; Taurand, S; Hervy, M P; Forette, F; Piette, F; Sebag-Lanoe, R; Alperovitch, A

1992-10-01

The aim was to compare digital and palmar dermatoglyphics in subjects with dementia of Alzheimer type and in mentally healthy elderly controls. This design was a case-control study. The study was carried out in geriatric units and retirement communities in the Paris area. Cases were women with clinically diagnosed Alzheimer type dementia according to DSM III-R criteria (n = 82), mainly with late onset of the disease. Controls were women aged 85 years or older without cognitive deterioration (n = 76). Finger and palm prints obtained from both hands by the classical ink method were examined. Fingerprints were classified into four types of figures. On palms, palmar flexion creases, palmar axial triradii, true patterns of the hypothenar area, and main line terminations were described. Examinations were performed by two examiners blind to the subjects's diagnostic category. For the different patterns studied, no major differences between dementia patients and elderly controls were found. Nor was there evidence of high frequencies of features commonly observed in Down's syndrome (trisomy 21), which have previously, though sporadically, been reported. On one of the largest samples of Alzheimer dementia patients studied, and with evaluation blind to diagnosis, no evidence has been found that particular dermatoglyphic patterns occur like those observed in Down's syndrome, a disease which is related to dementia of the Alzheimer type.

[Malaria and HIV infection: clinical and biological aspects at Donka National Hospital in Conakry, Guinea].

PubMed

Bald, I; Camara, A; Baldé, O; Magassouba, N F; Bah, M S; Makanéra, A; Gamy, E P

2010-08-01

Malaria and HIV/AIDS are two of the most widespread infectious diseases encountered in sub-Saharan Africa. Even minor interactions between these two diseases could have substantial effects on public health. The purpose of this study was to investigate associations between malaria and HIV infection. Study was carried out over an 8-month period (April 1, 2003 to November 30, 2003) in the Tropical and Infectious Diseases Department of the Donka National Hospital in Conakry, Guinea. A total of 89 malaria patients including 41 cases with HIV infection and 48 controls without HIV infection were included. All patients were hospitalized during the study and provided informed consent. Results showed that malaria affected all age groups in the same proportion. Mean patient age was 34 years (range, 15 and 76 years). Males were more frequently infected with a sex ratio of 1.05. The average number of malaria episodes was higher in cases (malaria with HIV-infection than in controls (malaria without HIV infection). Hyperthermia was observed in most cases (68.29%) and controls (77.08%). Severe anemia was observed in 26.82% of cases versus 10.41% of controls. Low parasite density was observed in 73.17% of cases as compared to 68.75% of controls. The recovery rate was higher in the control group than in case group: 27.08% versus 14.63%. The death rate was higher in the case group than in the control group: 21.95% versus 6.25%. These findings demonstrate a link between malaria and HIV. The frequency of malaria episodes was higher in patients with HIV infection than patients without HIV infection and the outcome of malarial episodes was better in patients without HIV infection.

Indirect Observation in Everyday Contexts: Concepts and Methodological Guidelines within a Mixed Methods Framework.

PubMed

Anguera, M Teresa; Portell, Mariona; Chacón-Moscoso, Salvador; Sanduvete-Chaves, Susana

2018-01-01

Indirect observation is a recent concept in systematic observation. It largely involves analyzing textual material generated either indirectly from transcriptions of audio recordings of verbal behavior in natural settings (e.g., conversation, group discussions) or directly from narratives (e.g., letters of complaint, tweets, forum posts). It may also feature seemingly unobtrusive objects that can provide relevant insights into daily routines. All these materials constitute an extremely rich source of information for studying everyday life, and they are continuously growing with the burgeoning of new technologies for data recording, dissemination, and storage. Narratives are an excellent vehicle for studying everyday life, and quantitization is proposed as a means of integrating qualitative and quantitative elements. However, this analysis requires a structured system that enables researchers to analyze varying forms and sources of information objectively. In this paper, we present a methodological framework detailing the steps and decisions required to quantitatively analyze a set of data that was originally qualitative. We provide guidelines on study dimensions, text segmentation criteria, ad hoc observation instruments, data quality controls, and coding and preparation of text for quantitative analysis. The quality control stage is essential to ensure that the code matrices generated from the qualitative data are reliable. We provide examples of how an indirect observation study can produce data for quantitative analysis and also describe the different software tools available for the various stages of the process. The proposed method is framed within a specific mixed methods approach that involves collecting qualitative data and subsequently transforming these into matrices of codes (not frequencies) for quantitative analysis to detect underlying structures and behavioral patterns. The data collection and quality control procedures fully meet the requirement of flexibility and provide new perspectives on data integration in the study of biopsychosocial aspects in everyday contexts.

[Mexidol in treatment of children with generalized epilepsy and febrile seizures].

PubMed

Natriashvili, G; Natriashvili, S; Kapanadze, N

2005-05-01

The aim of our study was to estimate the role of Mexidol in ceasing of epileptic fits and improving electroencephalographic (EEG) pathological patterns in children. 120 patients with generalized epilepsy (from 4 to 16 years old) were investigated. All patients were treated by Depakin chrono 30 mg/kg. Children were divided into 2 groups: 1st--study group consisted of 60 children with combined treatment with Depakin and Mexidol (5 mg/kg). In the control group (60 children) treatment was performed only by Depakin. 100 children with the first episode of febrile seizures (from 6 months to 4 years old) were investigated. 50 children composed the study group with monotheraphy by Mexidol and 50 patients--the control group, without any treatment. The EEG examination was done by computer EEG Topography "Brain Surveyor Saico". Using Depakin in combination with Mexidol in the study group of patients with generalized epilepsy, improvement of clinical picture of disease and normalization of EEG patterns in 93% of cases has been observed. In the study group of patients with febrile seizures, normalization of EEG pathological patterns was observed in 82% cases and in 18% its improvement was seen. The relapse of seizures at high temperature was observed in 3 patients. In control group EEG patterns were improved only in 20%, in 48% no positive effect was observed and in 41% the worsening of EEG findings was seen. The relapse of febrile seizures was observed in 26 cases. Mexidol titrated to the target doze of 5mg/kg may be effective in combination with Depakin for treatment of patients with generalized epilepsy and as monotherapy in patients with first episode of febrile seizures.

Immune involvement in the pathogenesis of schizophrenia: a meta-analysis on postmortem brain studies

PubMed Central

van Kesteren, C F M G; Gremmels, H; de Witte, L D; Hol, E M; Van Gool, A R; Falkai, P G; Kahn, R S; Sommer, I E C

2017-01-01

Although the precise pathogenesis of schizophrenia is unknown, genetic, biomarker and imaging studies suggest involvement of the immune system. In this study, we performed a systematic review and meta-analysis of studies investigating factors related to the immune system in postmortem brains of schizophrenia patients and healthy controls. Forty-one studies were included, reporting on 783 patients and 762 controls. We divided these studies into those investigating histological alterations of cellular composition and those assessing molecular parameters; meta-analyses were performed on both categories. Our pooled estimate on cellular level showed a significant increase in the density of microglia (P=0.0028) in the brains of schizophrenia patients compared with controls, albeit with substantial heterogeneity between studies. Meta-regression on brain regions demonstrated this increase was most consistently observed in the temporal cortex. Densities of macroglia (astrocytes and oligodendrocytes) did not differ significantly between schizophrenia patients and healthy controls. The results of postmortem histology are paralleled on the molecular level, where we observed an overall increase in expression of proinflammatory genes on transcript and protein level (P=0.0052) in patients, while anti-inflammatory gene expression levels were not different between schizophrenia and controls. The results of this meta-analysis strengthen the hypothesis that components of the immune system are involved in the pathogenesis of schizophrenia. PMID:28350400

Respiratory Sinus Arrhythmia, Effortful Control, and Parenting as Predictors of Children’s Sympathy Across Early Childhood

PubMed Central

Taylor, Zoe E.; Eisenberg, Nancy; Spinrad, Tracy L.

2015-01-01

The goal of this study was to examine physiological and environmental predictors of children’s sympathy (an emotional response consisting of feelings of concern or sorrow for others who are distressed or in need) and whether temperamental effortful control mediated these relations. Specifically, in a study of 192 children (23% Hispanic; 54% male), respiratory sinus arrhythmia (RSA), a measure thought to reflect physiological regulation, and observed authoritative parenting (both at 42 months) were examined as predictors of children’s effortful control (at 54 months) and, in turn, children’s sympathy (at 72 and 84 months). Measures of both baseline RSA and RSA suppression were examined. In a structural equation model, observed parenting was positively related to children’s subsequent sympathy through its positive relation to effortful control. Furthermore, the indirect path from baseline RSA to higher sympathy through effortful control was marginally significant. Authoritative parenting and baseline RSA uniquely predicted individual differences in children’s effortful control. Findings highlight the potential role of both authoritative parenting and physiological regulation in the development of children’s sympathy. PMID:25329555

Respiratory sinus arrhythmia, effortful control, and parenting as predictors of children's sympathy across early childhood.

PubMed

Taylor, Zoe E; Eisenberg, Nancy; Spinrad, Tracy L

2015-01-01

The goal of this study was to examine physiological and environmental predictors of children's sympathy (an emotional response consisting of feelings of concern or sorrow for others who are distressed or in need) and whether temperamental effortful control mediated these relations. Specifically, in a study of 192 children (23% Hispanic; 54% male), respiratory sinus arrhythmia (RSA), a measure thought to reflect physiological regulation, and observed authoritative parenting (both at 42 months) were examined as predictors of children's effortful control (at 54 months) and, in turn, children's sympathy (at 72 and 84 months). Measures of both baseline RSA and RSA suppression were examined. In a structural equation model, observed parenting was positively related to children's subsequent sympathy through its positive relation to effortful control. Furthermore, the indirect path from baseline RSA to higher sympathy through effortful control was marginally significant. Authoritative parenting and baseline RSA uniquely predicted individual differences in children's effortful control. Findings highlight the potential role of both authoritative parenting and physiological regulation in the development of children's sympathy.

Hemorrhage Control for Major Traumatic Vascular Injuries

DTIC Science & Technology

2017-10-01

subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO...aims: 1) Determine current practice patterns for the treatment of patients with NCTH among 4 clinical sites using a retrospective study design (Phase...competency, and training issues for catheter-based hemorrhage control (Phase 1b); 3) Conduct a prospective 4-site observational study to test the hypothesis

Case-control study of renal cell carcinoma in relation to occupation, smoking, and alcohol consumption

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

Brownson, R.C.

1988-05-01

A case-control study based on data from a cancer registry was conducted to evaluate the effects of smoking, alcohol use, and occupation on renal cell cancer risk. Information was obtained for 326 male and female cases and 978 age- and sex-matched controls. Elevated risks were identified for cigarette smokers and for men employed as truck drivers. No relationship between alcohol consumption and renal cancer was observed.

Expanding the Evidence Base: Comparing Randomized Controlled Trials and Observational Studies of Statins.

PubMed

Atar, Dan; Ong, Seleen; Lansberg, Peter J

2015-01-01

It is widely accepted that randomized controlled trials (RCTs) are the gold standard for demonstrating the efficacy of a given therapy (results under ideal conditions). Observational studies, on the other hand, can complement this by demonstrating effectiveness (results under real-world conditions). To examine the role that observational studies can play in complementing data from RCTs, we reviewed published studies for statins, a class of drugs that have been widely used to reduce the risk of cardiovascular (CV) events by lowering low-density lipoprotein cholesterol levels. RCTs have consistently demonstrated the benefits of statin treatment in terms of CV risk reduction and have demonstrated that more intensive statin therapy has incremental benefits over less intensive treatment. Observational studies of statin use in 'real-world' populations have served to augment the evidence base generated from statin RCTs in preselected populations of patients who are often at high CV risk and have led to similar safety and efficacy findings. They have also raised questions about factors affecting medication adherence, under-treatment, switching between statins, and failure to reach low-density lipoprotein cholesterol target levels, questions for which the answers could lead to improved patient care.

Inhibitory Control and Impulsivity Levels in Women Crack Users.

PubMed

Hess, Adriana Raquel Binsfeld; Menezes, Carolina B; de Almeida, Rosa Maria Martins

2018-05-12

investigate impulsivity levels and inhibitory control in women crack users and explore the relationships between impulsivity and inhibitory control. 52 healthy women (M = 32.83 years; SD = 9.54) and 46 crack cocaine users (M = 31.02 years; SD = 7.73), in abstinence, performed the assessment protocol included a Sociodemographic Data Questionnaire, Mini-Mental State Examination (MMSE), a GO/No-Go Task and the Barratt Impulsiveness Scale-11 (BIS-11). It was a quantitative research with cross-sectional design and control group. crack group showed higher levels of impulsivity in all domains when compared to the control group (crack group M = 76.39, SD = 11.39, control group M = 58.53, SD = 10.76, p <.01). Participants from the crack group presented a significantly higher total reaction time in the Go-NoGo task (F(1,93) = 9.93, p =.002; effect size =.09, observed power =.87) and significantly more commission (F(1,93) = 7.20, p =.009; effect size =.07, observed power =.75) and omission errors (F(1,93) = 6.04, p =.01; effect size =.06, observed power =.68), in Go/NoGo Task. Groups did also significantly differ on total standard deviations suggesting that variability in total reaction time was significantly greater in the crack group. Results showed that only in the crack group there were significant correlations between Go-NoGo parameters and Barratt Impulsiveness Scale. Our findings are consistent that impulsivity and inhibitory control are closely linked to crack use in women. Future studies should consider to evaluate crack users in different withdrawal times, controlling the impact of abstinence time in the variables studied.

Cruciferous vegetable intake is inversely associated with lung cancer risk among smokers: a case-control study

PubMed Central

2010-01-01

Background Inverse associations between cruciferous vegetable intake and lung cancer risk have been consistently reported. However, associations within smoking status subgroups have not been consistently addressed. Methods We conducted a hospital-based case-control study with lung cancer cases and controls matched on smoking status, and further adjusted for smoking status, duration, and intensity in the multivariate models. A total of 948 cases and 1743 controls were included in the analysis. Results Inverse linear trends were observed between intake of fruits, total vegetables, and cruciferous vegetables and risk of lung cancer (ORs ranged from 0.53-0.70, with P for trend < 0.05). Interestingly, significant associations were observed for intake of fruits and total vegetables with lung cancer among never smokers. Conversely, significant inverse associations with cruciferous vegetable intake were observed primarily among smokers, in particular former smokers, although significant interactions were not detected between smoking and intake of any food group. Of four lung cancer histological subtypes, significant inverse associations were observed primarily among patients with squamous or small cell carcinoma - the two subtypes more strongly associated with heavy smoking. Conclusions Our findings are consistent with the smoking-related carcinogen-modulating effect of isothiocyanates, a group of phytochemicals uniquely present in cruciferous vegetables. Our data support consumption of a diet rich in cruciferous vegetables may reduce the risk of lung cancer among smokers. PMID:20423504

Systematic Review of the Literature on Pain in Patients with Polytrauma Including Traumatic Brain Injury

PubMed Central

Dobscha, Steven K.; Clark, Michael E.; Morasco, Benjamin J.; Freeman, Michele; Campbell, Rose; Helfand, Mark

2010-01-01

Objective To review the literature addressing the assessment and management of pain in patients with polytraumatic injuries including traumatic brain injury (TBI) and blast-related headache, and to identify patient, clinician and systems factors associated with pain-related outcomes. Design Systematic review. Methods We conducted searches in MEDLINE of literature published from 1950 through July 2008. Due to a limited number of studies using controls or comparators, we included observational and rigorous qualitative studies. We systematically rated the quality of systematic reviews, cohort, and case-control design studies. Results One systematic review, 93 observational studies, and one qualitative research study met inclusion criteria. The literature search yielded no published studies that assessed measures of pain intensity or pain-related functional interference among patients with cognitive deficits due to TBI, that compared patients with blast-related headache with patients with other types of headache, or that assessed treatments for blast-related headache pain. Studies on the association between TBI severity and pain reported mixed findings. There was limited evidence that the following factors are associated with pain among TBI patients: severity, location, and multiplicity of injuries; insomnia; fatigue; depression; and post-traumatic stress disorder. Conclusions Very little evidence is currently available to guide pain assessment and treatment approaches in patients with polytrauma. Further research employing systematic observational as well as controlled intervention designs is clearly indicated. PMID:19818031

Neural systems for preparatory control of imitation.

PubMed

Cross, Katy A; Iacoboni, Marco

2014-01-01

Humans have an automatic tendency to imitate others. Previous studies on how we control these tendencies have focused on reactive mechanisms, where inhibition of imitation is implemented after seeing an action. This work suggests that reactive control of imitation draws on at least partially specialized mechanisms. Here, we examine preparatory imitation control, where advance information allows control processes to be employed before an action is observed. Drawing on dual route models from the spatial compatibility literature, we compare control processes using biological and non-biological stimuli to determine whether preparatory imitation control recruits specialized neural systems that are similar to those observed in reactive imitation control. Results indicate that preparatory control involves anterior prefrontal, dorsolateral prefrontal, posterior parietal and early visual cortices regardless of whether automatic responses are evoked by biological (imitative) or non-biological stimuli. These results indicate both that preparatory control of imitation uses general mechanisms, and that preparatory control of imitation draws on different neural systems from reactive imitation control. Based on the regions involved, we hypothesize that preparatory control is implemented through top-down attentional biasing of visual processing.

Treatment of allergic rhinitis using mobile technology with real-world data: The MASK observational pilot study.

PubMed

Bousquet, J; Devillier, P; Arnavielhe, S; Bedbrook, A; Alexis-Alexandre, G; van Eerd, M; Murray, R; Canonica, G W; Illario, M; Menditto, E; Passalacqua, G; Stellato, C; Triggiani, M; Carreiro-Martins, P; Fonseca, J; Morais Almeida, M; Nogueira-Silva, L; Pereira, A M; Todo Bom, A; Bosse, I; Caimmi, D; Demoly, P; Fontaine, J F; Just, J; Onorato, G L; Kowalski, M L; Kuna, P; Samolinski, B; Anto, J M; Mullol, J; Valero, A; Tomazic, P V; Bergmann, K C; Keil, T; Klimek, L; Mösges, R; Shamai, S; Zuberbier, T; Murphy, E; McDowall, P; Price, D; Ryan, D; Sheikh, A; Chavannes, N H; Fokkens, W J; Kvedariene, V; Valiulis, A; Bachert, C; Hellings, P W; Kull, I; Melen, E; Wickman, M; Bindslev-Jensen, C; Eller, E; Haahtela, T; Papadopoulos, N G; Annesi-Maesano, I; Bewick, M; Bosnic-Anticevich, S; Cruz, A A; De Vries, G; Gemicioglu, B; Larenas-Linnemann, D; Laune, D; Mathieu-Dupas, E; O'Hehir, R E; Pfaar, O; Portejoie, F; Siroux, V; Spranger, O; Valovirta, E; VandenPlas, O; Yorgancioglu, A

2018-01-15

Large observational implementation studies are needed to triangulate the findings from randomized control trials as they reflect "real-world" everyday practice. In a pilot study, we attempted to provide additional and complementary insights on the real-life treatment of allergic rhinitis (AR) using mobile technology. A mobile phone app (Allergy Diary, freely available in Google Play and Apple App stores) collects the data of daily visual analog scales (VAS) for (i) overall allergic symptoms, (ii) nasal, ocular, and asthma symptoms, (iii) work, as well as (iv) medication use using a treatment scroll list including all medications (prescribed and over the counter (OTC)) for rhinitis customized for 15 countries. A total of 2871 users filled in 17 091 days of VAS in 2015 and 2016. Medications were reported for 9634 days. The assessment of days appeared to be more informative than the course of the treatment as, in real life, patients do not necessarily use treatment on a daily basis; rather, they appear to increase treatment use with the loss of symptom control. The Allergy Diary allowed differentiation between treatments within or between classes (intranasal corticosteroid use containing medications and oral H1-antihistamines). The control of days differed between no [best control], single, or multiple treatments (worst control). This study confirms the usefulness of the Allergy Diary in accessing and assessing everyday use and practice in AR. This pilot observational study uses a very simple assessment (VAS) on a mobile phone, shows novel findings, and generates new hypotheses. © 2018 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd.

Maternal exposures in the National Birth Defects Prevention Study: time trends of selected exposures

PubMed Central

Dawson, April L.; Razzaghi, Hilda; Arth, Annelise; Canfield, Mark A.; Parker, Samantha E.; Reefhuis, Jennita

2015-01-01

Background Our objective was to describe time trends in selected pregnancy exposures in the National Birth Defects Prevention Study (NBDPS). Methods We analyzed data from the NBDPS, a multi-site case-control study of major birth defects, for mothers of live-born infants without birth defects (controls), with an expected date of delivery (EDD) from 1998 –2011. Mothers from the 10 participating centers across the United States were interviewed by phone between six weeks and two years after the EDD. We focused on maternal race/ethnicity and five maternal risk factors: obesity, use of folic acid-containing multivitamins, opioid analgesics, selective serotonin reuptake inhibitors (SSRIs), and loratadine because of their prevalence of use and some reports of associations with major birth defects. Prevalence time trends were examined using the Kendall’s τβ test statistic. Results The exposure trend analysis included 11,724 control mothers with EDDs from 1998–2011. We observed a significant increase in obesity prevalence among control mothers, as well as use of SSRIs and loratadine. We also observed an increase in periconceptional use of folic acid-containing multivitamins. Some of the time trends varied by race/ethnicity. No remarkable trend in the overall use of opioid analgesics was observed. The racial/ethnic distribution of mothers changed slightly during the study period. Conclusions Long-term, population-based case-control studies continue to be an effective way to assess exposure-birth defects associations and provide guidance to health care providers. However, investigators examining rare outcomes covering many years of data collection need to be cognizant of time trends in exposures. PMID:25884728

Maternal exposures in the National Birth Defects Prevention Study: Time trends of selected exposures.

PubMed

Dawson, April L; Razzaghi, Hilda; Arth, Annelise; Canfield, Mark A; Parker, Samantha E; Reefhuis, Jennita

2015-08-01

Our objective was to describe time trends in selected pregnancy exposures in the National Birth Defects Prevention Study (NBDPS). We analyzed data from the NBDPS, a multi-site case-control study of major birth defects, for mothers of live-born infants without birth defects (controls), with an expected date of delivery (EDD) from 1998 to 2011. Mothers from the 10 participating centers across the United States were interviewed by phone between 6 weeks and 2 years after the EDD. We focused on maternal race/ethnicity and five maternal risk factors: obesity, use of folic acid-containing multivitamins, opioid analgesics, selective serotonin reuptake inhibitors, and loratadine because of their prevalence of use and some reports of associations with major birth defects. Prevalence time trends were examined using the Kendall's τβ test statistic. The exposure trend analysis included 11,724 control mothers with EDDs from 1998 to 2011. We observed a significant increase in obesity prevalence among control mothers, as well as use of selective serotonin reuptake inhibitors and loratadine. We also observed an increase in periconceptional use of folic acid-containing multivitamins. Some of the time trends varied by race/ethnicity. No remarkable trend in the overall use of opioid analgesics was observed. The racial/ethnic distribution of mothers changed slightly during the study period. Long-term, population-based case-control studies continue to be an effective way to assess exposure-birth defects associations and provide guidance to health care providers. However, investigators examining rare outcomes covering many years of data collection need to be cognizant of time trends in exposures. © 2015 Wiley Periodicals, Inc.

The effect of rubber flooring on displaying stereotypies in gilts.

PubMed

Ostović, Mario; Menčik, Sven; Kabalin, Anamaria Ekert; Gračner, Gordana Gregurić; Vučemilo, Marija; Matković, Kristina; Vukičević, Tajana Trbojević; Grahovac, Jurica; Pavičić, Zeljko

2015-01-01

The aim of the study was to assess the effect of rubber mats in service unit on displaying stereotypies in gilts. Four 28-day production cycles in all seasons were observed. Each cycle included 28 gilts housed in gestation stalls with slatted concrete floor, which was covered with adjusted mats for 14 gilts (experimental group), while the remaining 14 gilts served as controls. Display of stereotypies and other behaviours observed, mat manipulation and postural behaviours were estimated by direct 1-hour observation of gilts at 2-minute intervals after morning feed supply on days 1, 8, 15 and 28 of each cycle. During the study period, displaying stereotypies was significantly less frequent (P < 0.05) in experimental group as compared with control group. The rate of particular forms of stereotypies, i.e. vacuum chewing, bar biting and teeth grinding, was also significantly lower (P < 0.05 all) in experimental group throughout the study period. A significant negative correlation (P <.05) was found between the service unit air temperature and frequency of displaying stereotypies in control group, which could be attributed to the significantly more common standing posture (P < 0.05) in control gilts in the conditions of lower air temperature. During the cold period, experimental gilts took a lying position significantly more frequently (P < 0.05). In the experimental group of gilts there was no significant correlation (P > 0.05 all) between the frequency of displaying stereotypies and the frequency of lying and other postures observed, as well as between the stereotypy display and the air temperature. There was no significant correlation (P > 0.05 all) between the frequency of mat manipulation and displaying stereotypies in total or its particular forms, suggesting that the less pronounced stereotypy display in experimental gilts may have been influenced by factors other than those observed in the present study.

Microvascular diabetes complications in Wolfram syndrome (diabetes insipidus, diabetes mellitus, optic atrophy, and deafness [DIDMOAD]): an age- and duration-matched comparison with common type 1 diabetes.

PubMed

Cano, Aline; Molines, Laurent; Valéro, René; Simonin, Gilbert; Paquis-Flucklinger, Véronique; Vialettes, Bernard

2007-09-01

Some previous studies suggested that patients suffering from Wolfram syndrome or DIDMOAD (diabetes insipidus, diabetes mellitus, optic atrophy, and deafness) might be relatively preserved from diabetic retinopathy and nephropathy. However, these data were not conclusive because either observations were only anecdotic or did not match with control type 1 diabetic populations. A group of 26 French diabetic patients with DIDMOAD was compared with a population of 52 patients with common type 1 diabetes matched for age at diabetes diagnosis (8.62 +/- 1.84 vs. 8.27 +/- 1.30 years; P = NS) and diabetes duration (12.88 +/- 1.58 vs. 12.87 +/- 1.13 years; P = NS) to study the quality of glycemic control and the incidence of microvascular complications. Glycemic control was significantly better in the DIDMOAD group than in the type 1 diabetic group (A1C: 7.72 +/- 0.21 vs. 8.99 +/- 0.25%, respectively; P = 0.002), with significant lower daily insulin requirements (0.71 +/- 0.07 vs. 0.88 +/- 0.04 UI x kg(-1) x day(-1), respectively; P = 0.0325). The prevalence of microvascular complications in the DIDMOAD group was half that observed in the type 1 diabetic group, but the difference was not significant. Diabetes in DIDMOAD patients is more easily controlled despite the presence of other handicaps. This better glycemic control could explain the trend to decreased microvascular diabetes complications observed in previous studies.

Minimal time spiking in various ChR2-controlled neuron models.

PubMed

Renault, Vincent; Thieullen, Michèle; Trélat, Emmanuel

2018-02-01

We use conductance based neuron models, and the mathematical modeling of optogenetics to define controlled neuron models and we address the minimal time control of these affine systems for the first spike from equilibrium. We apply tools of geometric optimal control theory to study singular extremals, and we implement a direct method to compute optimal controls. When the system is too large to theoretically investigate the existence of singular optimal controls, we observe numerically the optimal bang-bang controls.

Measurement Error Correction Formula for Cluster-Level Group Differences in Cluster Randomized and Observational Studies

ERIC Educational Resources Information Center

Cho, Sun-Joo; Preacher, Kristopher J.

2016-01-01

Multilevel modeling (MLM) is frequently used to detect cluster-level group differences in cluster randomized trial and observational studies. Group differences on the outcomes (posttest scores) are detected by controlling for the covariate (pretest scores) as a proxy variable for unobserved factors that predict future attributes. The pretest and…

Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of observational studies and randomised trials

PubMed Central

Tzoulaki, Ioanna; Zgaga, Lina; Ioannidis, John P A

2014-01-01

Objective To evaluate the breadth, validity, and presence of biases of the associations of vitamin D with diverse outcomes. Design Umbrella review of the evidence across systematic reviews and meta-analyses of observational studies of plasma 25-hydroxyvitamin D or 1,25-dihydroxyvitamin D concentrations and randomised controlled trials of vitamin D supplementation. Data sources Medline, Embase, and screening of citations and references. Eligibility criteria Three types of studies were eligible for the umbrella review: systematic reviews and meta-analyses that examined observational associations between circulating vitamin D concentrations and any clinical outcome; and meta-analyses of randomised controlled trials assessing supplementation with vitamin D or active compounds (both established and newer compounds of vitamin D). Results 107 systematic literature reviews and 74 meta-analyses of observational studies of plasma vitamin D concentrations and 87 meta-analyses of randomised controlled trials of vitamin D supplementation were identified. The relation between vitamin D and 137 outcomes has been explored, covering a wide range of skeletal, malignant, cardiovascular, autoimmune, infectious, metabolic, and other diseases. Ten outcomes were examined by both meta-analyses of observational studies and meta-analyses of randomised controlled trials, but the direction of the effect and level of statistical significance was concordant only for birth weight (maternal vitamin D status or supplementation). On the basis of the available evidence, an association between vitamin D concentrations and birth weight, dental caries in children, maternal vitamin D concentrations at term, and parathyroid hormone concentrations in patients with chronic kidney disease requiring dialysis is probable, but further studies and better designed trials are needed to draw firmer conclusions. In contrast to previous reports, evidence does not support the argument that vitamin D only supplementation increases bone mineral density or reduces the risk of fractures or falls in older people. Conclusions Despite a few hundred systematic reviews and meta-analyses, highly convincing evidence of a clear role of vitamin D does not exist for any outcome, but associations with a selection of outcomes are probable. PMID:24690624

[Post-stroke speech disorder treated with acupuncture and psychological intervention combined with rehabilitation training: a randomized controlled trial].

PubMed

Wang, Ling; Liu, Shao-ming; Liu, Min; Li, Bao-jun; Hui, Zhen-liang; Gao, Xiang

2011-06-01

To assess the clinical efficacy on post-stroke speech disorder treated with acupuncture and psychological intervention combined with rehabilitation training. The multi-central randomized controlled study was adopted. One hundred and twenty cases of brain stroke were divided into a speech rehabilitation group (control group), a speech rehabilitation plus acupuncture group (observation group 1) and a speech rehabilitation plus acupuncture combined with psychotherapy group (observation group 2), 40 cases in each one. The rehabilitation training was conducted by a professional speech trainer. In acupuncture treatment, speech function area in scalp acupuncture, Jinjin (EX-HN 12) and Yuye (EX-HN 13) in tongue acupuncture and Lianquan (CV 23) were the basic points. The supplementary points were selected according to syndrome differentiation. Bloodletting method was used in combination with acupuncture. Psychotherapy was applied by the physician in psychiatric department of the hospital. The corresponding programs were used in each group. Examination of Aphasia of Chinese of Beijing Hospital was adopted to observe the oral speech expression, listening comprehension and reading and writing ability. After 21-day treatment, the total effective rate was 92.5% (37/40) in observation group 1, 97.5% (39/40) in observation group 2 and 87.5% (35/40) in control group. The efficacies were similar in comparison among 3 groups. The remarkable effective rate was 15.0% (6/40) in observation group 1, 50.0% (20/40) in observation group 2 and 2.5% (1/40) in control group. The result in observation group 2 was superior to the other two groups (P<0.01, P<0.001). In comparison of the improvements of oral expression, listening comprehension, reading and writing ability, all of the 3 groups had achieved the improvements to different extents after treatment (P<0.01, P<0.001). The results in observation group 2 were better than those in observation group 1 and control group. Acupuncture and psychological intervention combined with rehabilitation training is obviously advantageous in the treatment of post-stroke speech disorder.

Childhood brain tumours and use of mobile phones: comparison of a case–control study with incidence data

PubMed Central

2012-01-01

The first case–control study on mobile phone use and brain tumour risk among children and adolescents (CEFALO study) has recently been published. In a commentary published in Environmental Health, Söderqvist and colleagues argued that CEFALO suggests an increased brain tumour risk in relation to wireless phone use. In this article, we respond and show why consistency checks of case–control study results with observed time trends of incidence rates are essential, given the well described limitations of case–control studies and the steep increase of mobile phone use among children and adolescents during the last decade. There is no plausible explanation of how a notably increased risk from use of wireless phones would correspond to the relatively stable incidence time trends for brain tumours among children and adolescents observed in the Nordic countries. Nevertheless, an increased risk restricted to heavy mobile phone use, to very early life exposure, or to rare subtypes of brain tumours may be compatible with stable incidence trends at this time and thus further monitoring of childhood brain tumour incidence rate time trends is warranted. PMID:22607537

A virtual reality-based system integrated with fmri to study neural mechanisms of action observation-execution: A proof of concept study

PubMed Central

Adamovich, S.V.; August, K.; Merians, A.; Tunik, E.

2017-01-01

Purpose Emerging evidence shows that interactive virtual environments (VEs) may be a promising tool for studying sensorimotor processes and for rehabilitation. However, the potential of VEs to recruit action observation-execution neural networks is largely unknown. For the first time, a functional MRI-compatible virtual reality system (VR) has been developed to provide a window into studying brain-behavior interactions. This system is capable of measuring the complex span of hand-finger movements and simultaneously streaming this kinematic data to control the motion of representations of human hands in virtual reality. Methods In a blocked fMRI design, thirteen healthy subjects observed, with the intent to imitate (OTI), finger sequences performed by the virtual hand avatar seen in 1st person perspective and animated by pre-recorded kinematic data. Following this, subjects imitated the observed sequence while viewing the virtual hand avatar animated by their own movement in real-time. These blocks were interleaved with rest periods during which subjects viewed static virtual hand avatars and control trials in which the avatars were replaced with moving non-anthropomorphic objects. Results We show three main findings. First, both observation with intent to imitate and imitation with real-time virtual avatar feedback, were associated with activation in a distributed frontoparietal network typically recruited for observation and execution of real-world actions. Second, we noted a time-variant increase in activation in the left insular cortex for observation with intent to imitate actions performed by the virtual avatar. Third, imitation with virtual avatar feedback (relative to the control condition) was associated with a localized recruitment of the angular gyrus, precuneus, and extrastriate body area, regions which are (along with insular cortex) associated with the sense of agency. Conclusions Our data suggest that the virtual hand avatars may have served as disembodied training tools in the observation condition and as embodied “extensions” of the subject’s own body (pseudo-tools) in the imitation. These data advance our understanding of the brain-behavior interactions when performing actions in VE and have implications in the development of observation- and imitation-based VR rehabilitation paradigms. PMID:19531876

Study design and "evidence" in patient-oriented research.

PubMed

Concato, John

2013-06-01

Individual studies in patient-oriented research, whether described as "comparative effectiveness" or using other terms, are based on underlying methodological designs. A simple taxonomy of study designs includes randomized controlled trials on the one hand, and observational studies (such as case series, cohort studies, and case-control studies) on the other. A rigid hierarchy of these design types is a fairly recent phenomenon, promoted as a tenet of "evidence-based medicine," with randomized controlled trials receiving gold-standard status in terms of producing valid results. Although randomized trials have many strengths, and contribute substantially to the evidence base in clinical care, making presumptions about the quality of a study based solely on category of research design is unscientific. Both the limitations of randomized trials as well as the strengths of observational studies tend to be overlooked when a priori assumptions are made. This essay presents an argument in support of a more balanced approach to evaluating evidence, and discusses representative examples from the general medical as well as pulmonary and critical care literature. The simultaneous consideration of validity (whether results are correct "internally") and generalizability (how well results apply to "external" populations) is warranted in assessing whether a study's results are accurate for patients likely to receive the intervention-examining the intersection of clinical and methodological issues in what can be called a medicine-based evidence approach. Examination of cause-effect associations in patient-oriented research should recognize both the strengths and limitations of randomized trials as well as observational studies.

Tuberculosis infection control measures in health care facilities offering tb services in Ikeja local government area, Lagos, South West, Nigeria.

PubMed

Kuyinu, Y A; Mohammed, A S; Adeyeye, O O; Odugbemi, B A; Goodman, O O; Odusanya, O O

2016-03-15

Tuberculosis infection among health care workers is capable of worsening the existing health human resource problems of low--and middle-income countries. Tuberculosis infection control is often weakly implemented in these parts of the world therefore, understanding the reasons for poor implementation of tuberculosis infection control guidelines are important. This study was aimed at assessing tuberculosis infection control practices and barriers to its implementation in Ikeja, Nigeria. A cross-sectional study in 20 tuberculosis care facilities (16 public and 4 private) in Ikeja, Lagos was conducted. The study included a facility survey to assess the availability of tuberculosis infection control guidelines, the adequacy of facilities to prevent transmission of tuberculosis and observations of practices to assess the implementation of tuberculosis infection control guidelines. Four focus group discussions were carried out to highlight HCWs' perceptions on tuberculosis infection control guidelines and barriers to its implementation. The observational study showed that none of the clinics had a tuberculosis infection control plan. No clinic was consistently screening patients for cough. Twelve facilities (60%) consistently provided masks to patients who were coughing. Ventilation in the waiting areas was assessed to be adequate in 60% of the clinics while four clinics (20%) possessed N-95 respirators. Findings from the focus group discussions showed weak managerial support, poor funding, under-staffing, lack of space and not wanting to be seen as stigmatizing against tuberculosis patients as barriers that hindered the implementation of TB infection control measures. Tuberculosis infection control measures were not adequately implemented in health facilities in Ikeja, Nigeria. A multi-pronged approach is required to address the identified barriers to the implementation of tuberculosis infection control guidelines.

Mother-Child Interactions and Childhood OCD: Effects of CBT on Mother and Child Observed Behaviors

ERIC Educational Resources Information Center

Schlup, Barbara; Farrell, Lara; Barrett, Paula

2011-01-01

This waitlist-controlled study investigates the impact of a group-based cognitive-behavioral therapy with family involvement (CBT-F) on observed mother and child behaviors in children with obsessive-compulsive disorder (OCD). Forty-four children and adolescents with OCD and their mothers were observed during family discussions before and after…

Multi-scale Drivers of Variations in Atmospheric Evaporative Demand Based on Observations and Physically-based Modeling

NASA Astrophysics Data System (ADS)

Peng, L.; Sheffield, J.; Li, D.

2015-12-01

Evapotranspiration (ET) is a key link between the availability of water resources and climate change and climate variability. Variability of ET has important environmental and socioeconomic implications for managing hydrological hazards, food and energy production. Although there have been many observational and modeling studies of ET, how ET has varied and the drivers of the variations at different temporal scales remain elusive. Much of the uncertainty comes from the atmospheric evaporative demand (AED), which is the combined effect of radiative and aerodynamic controls. The inconsistencies among modeled AED estimates and the limited observational data may originate from multiple sources including the limited time span and uncertainties in the data. To fully investigate and untangle the intertwined drivers of AED, we present a spectrum analysis to identify key controls of AED across multiple temporal scales. We use long-term records of observed pan evaporation for 1961-2006 from 317 weather stations across China and physically-based model estimates of potential evapotranspiration (PET). The model estimates are based on surface meteorology and radiation derived from reanalysis, satellite retrievals and station data. Our analyses show that temperature plays a dominant role in regulating variability of AED at the inter-annual scale. At the monthly and seasonal scales, the primary control of AED shifts from radiation in humid regions to humidity in dry regions. Unlike many studies focusing on the spatial pattern of ET drivers based on a traditional supply and demand framework, this study underlines the importance of temporal scales when discussing controls of ET variations.

An autonomous observation and control system based on EPICS and RTS2 for Antarctic telescopes

NASA Astrophysics Data System (ADS)

Zhang, Guang-yu; Wang, Jian; Tang, Peng-yi; Jia, Ming-hao; Chen, Jie; Dong, Shu-cheng; Jiang, Fengxin; Wu, Wen-qing; Liu, Jia-jing; Zhang, Hong-fei

2016-01-01

For unattended telescopes in Antarctic, the remote operation, autonomous observation and control are essential. An EPICS-(Experimental Physics and Industrial Control System) and RTS2-(Remote Telescope System, 2nd Version) based autonomous observation and control system with remoted operation is introduced in this paper. EPICS is a set of open source software tools, libraries and applications developed collaboratively and used worldwide to create distributed soft real-time control systems for scientific instruments while RTS2 is an open source environment for control of a fully autonomous observatory. Using the advantage of EPICS and RTS2, respectively, a combined integrated software framework for autonomous observation and control is established that use RTS2 to fulfil the function of astronomical observation and use EPICS to fulfil the device control of telescope. A command and status interface for EPICS and RTS2 is designed to make the EPICS IOC (Input/Output Controller) components integrate to RTS2 directly. For the specification and requirement of control system of telescope in Antarctic, core components named Executor and Auto-focus for autonomous observation is designed and implemented with remote operation user interface based on browser-server mode. The whole system including the telescope is tested in Lijiang Observatory in Yunnan Province for practical observation to complete the autonomous observation and control, including telescope control, camera control, dome control, weather information acquisition with the local and remote operation.

Span of control matters.

PubMed

Cathcart, Deb; Jeska, Susan; Karnas, Joan; Miller, Sue E; Pechacek, Judy; Rheault, Lolita

2004-09-01

Prompted by manager concerns about span of control, a large, integrated health system set out to determine if span of control really mattered. Was there something to it, or was it just an excuse for poor performance? A team of middle managers studied the problem and ultimately demonstrated a strong relationship between span of control and employee engagement. Consequently, it was decided to add 4 management positions to note the effect. One year later, positive changes were observed in employee engagement scores in all 4 areas. This study suggests careful review of manager spans of control to address the untoward effects of large spans of control on employee engagement.

Observational methods in comparative effectiveness research.

PubMed

Concato, John; Lawler, Elizabeth V; Lew, Robert A; Gaziano, J Michael; Aslan, Mihaela; Huang, Grant D

2010-12-01

Comparative effectiveness research (CER) may be defined informally as an assessment of available options for treating specific medical conditions in selected groups of patients. In this context, the most prominent features of CER are the various patient populations, medical ailments, and treatment options involved in any particular project. Yet, each research investigation also has a corresponding study design or "architecture," and in patient-oriented research a common distinction used to describe such designs are randomized controlled trials (RCTs) versus observational studies. The purposes of this overview, with regard to CER, are to (1) understand how observational studies can provide accurate results, comparable to RCTs; (2) recognize strategies used in selected newer methods for conducting observational studies; (3) review selected observational studies from the Veterans Health Administration; and (4) appreciate the importance of fundamental methodological principles when conducting or evaluating individual studies. Published by Elsevier Inc.

Marine Vehicle Sensor Network Architecture and Protocol Designs for Ocean Observation

PubMed Central

Zhang, Shaowei; Yu, Jiancheng; Zhang, Aiqun; Yang, Lei; Shu, Yeqiang

2012-01-01

The micro-scale and meso-scale ocean dynamic processes which are nonlinear and have large variability, have a significant impact on the fisheries, natural resources, and marine climatology. A rapid, refined and sophisticated observation system is therefore needed in marine scientific research. The maneuverability and controllability of mobile sensor platforms make them a preferred choice to establish ocean observing networks, compared to the static sensor observing platform. In this study, marine vehicles are utilized as the nodes of mobile sensor networks for coverage sampling of a regional ocean area and ocean feature tracking. A synoptic analysis about marine vehicle dynamic control, multi vehicles mission assignment and path planning methods, and ocean feature tracking and observing techniques is given. Combined with the observation plan in the South China Sea, we provide an overview of the mobile sensor networks established with marine vehicles, and the corresponding simulation results. PMID:22368475

Influence of Parenting Factors on Childhood Social Anxiety: Direct Observation of Parental Warmth and Control

ERIC Educational Resources Information Center

Rork, Kristine E.; Morris, Tracy L.

2009-01-01

The purpose of the present study is to determine the association of parenting behaviors and social anxiety in children. Three parental factors--including parental socialization, control, and warmth--were investigated in a sample of 31 two-parent families. Rather than solely relying upon retrospective questionnaires, this study incorporated direct…

Experimental and theoretical studies of active control of resistive wall mode growth in the EXTRAP T2R reversed-field pinch

NASA Astrophysics Data System (ADS)

Drake, J. R.; Brunsell, P. R.; Yadikin, D.; Cecconello, M.; Malmberg, J. A.; Gregoratto, D.; Paccagnella, R.; Bolzonella, T.; Manduchi, G.; Marrelli, L.; Ortolani, S.; Spizzo, G.; Zanca, P.; Bondeson, A.; Liu, Y. Q.

2005-07-01

Active feedback control of resistive wall modes (RWMs) has been demonstrated in the EXTRAP T2R reversed-field pinch experiment. The control system includes a sensor consisting of an array of magnetic coils (measuring mode harmonics) and an actuator consisting of a saddle coil array (producing control harmonics). Closed-loop (feedback) experiments using a digital controller based on a real time Fourier transform of sensor data have been studied for cases where the feedback gain was constant and real for all harmonics (corresponding to an intelligent-shell) and cases where the feedback gain could be set for selected harmonics, with both real and complex values (targeted harmonics). The growth of the dominant RWMs can be reduced by feedback for both the intelligent-shell and targeted-harmonic control systems. Because the number of toroidal positions of the saddle coils in the array is half the number of the sensors, it is predicted and observed experimentally that the control harmonic spectrum has sidebands. Individual unstable harmonics can be controlled with real gains. However if there are two unstable mode harmonics coupled by the sideband effect, control is much less effective with real gains. According to the theory, complex gains give better results for (slowly) rotating RWMs, and experiments support this prediction. In addition, open loop experiments have been used to observe the effects of resonant field errors applied to unstable, marginally stable and robustly stable modes. The observed effects of field errors are consistent with the thin-wall model, where mode growth is proportional to the resonant field error amplitude and the wall penetration time for that mode harmonic.

Blood glucose control and quality of health care in non-insulin-treated patients with Type 2 diabetes in Spain: a retrospective and cross-sectional observational study

PubMed Central

Rodríguez, A; Calle, A; Vázquez, L; Chacón, F; Polavieja, P; Reviriego, J

2011-01-01

Aims To assess blood glucose control and quality of health care provided to non-insulin-treated patients with Type 2 diabetes mellitus in routine clinical practice in Spain. Methods In this observational, retrospective, cross-sectional study, patients were grouped as either having good or suboptimal blood glucose control according to International Diabetes Federation or American Diabetes Association HbA1c goals. Clinical and socio-demographic data and compliance with the main standard level of care recommendations of the International Diabetes Federation were recorded during a routine visit. Correlates of glucose control were analysed by logistic regression. Results Many patients were grouped as having suboptimal control under International Diabetes Federation (61.9%) or American Diabetes Association (45.0%) criteria. The mean number of accomplished International Diabetes Federation recommendations (7.3 out of 11) was higher for endocrinologists (than for internists or primary care physicians), and significantly more patients under their care were in the good glucose control group (than with primary care physicians). More recommendations were associated with blood glucose control using International Diabetes Federation than American Diabetes Association criteria, demanding higher quality of health care for achieving stricter goals. Some recommendations were poorly observed, particularly those concerning patients’ education on diabetes, the prompt prescription of effective treatments and monitoring of complications. Diabetes complications were associated with being in the suboptimal control group. Patients’ education on diabetes and HbA1c monitoring were associated with being in the good control group. Conclusions These results demonstrate the need for improvement in the management of patients with non-insulin-treated Type 2 diabetes in actual clinical practice in Spain. Such improvement would entail a stricter adherence to International Diabetes Federation recommendations. PMID:21294772

A visual processing advantage for young-adolescent deaf observers: Evidence from face and object matching tasks

PubMed Central

Megreya, Ahmed M.; Bindemann, Markus

2017-01-01

It is unresolved whether the permanent auditory deprivation that deaf people experience leads to the enhanced visual processing of faces. The current study explored this question with a matching task in which observers searched for a target face among a concurrent lineup of ten faces. This was compared with a control task in which the same stimuli were presented upside down, to disrupt typical face processing, and an object matching task. A sample of young-adolescent deaf observers performed with higher accuracy than hearing controls across all of these tasks. These results clarify previous findings and provide evidence for a general visual processing advantage in deaf observers rather than a face-specific effect. PMID:28117407

Assessment of short reports using a human rights-based approach to tobacco control to the Commitee on Economics, Cultural and Social Rights.

PubMed

Dresler, Carolyn; Henry, Kirsten; Loftus, John; Lando, Harry

2017-07-28

The health impact of tobacco use remains a major global public health concern and a human rights issue. The Human Rights and Tobacco Control Network (HRTCN) was established to increase the visibility of tobacco as a human rights issue. HRTCN submitted short reports to the UN Committee on Economic Social and Cultural Rights evaluating individual nations' tobacco control policies and offering recommendations. HRTCN reviewed Concluding Observations documents for nations for which the HRTCN submitted reports. If tobacco was mentioned in the Concluding Observations through acknowledging the Framework Convention on Tobacco Control ratification, policy changes or discussing tobacco in the recommendations, this was scored as a positive finding. HRTCN also reviewed Concluding Observations for nations for which HRTCN did not submit reports as a comparison. Thirty-eight HRTCN reports were submitted and tobacco was mentioned in Concluding Observations for 11 nations for a rate of 28.9%. In a comparison set of Concluding Observations (n=59), 7% had comments or recommendations relative to tobacco. This was not a controlled study and the 28.9% 'success rate' for impacting the Concluding Observations, although encouraging, is less than optimal-and leaves room for improvement. The higher rate of tobacco mentions for the cases where the HRTCN short reports were submitted provides preliminary indications that the short reports may have potential to increase the state focus on tobacco control. Future work will seek to improve the design and scope of the reports, and the specificity of the background information and recommendations offered. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Equatorial Precession in the Control Software of the Ka-Band Object Observation and Monitoring Experiment

NASA Technical Reports Server (NTRS)

Jakeman, Hali L.

2013-01-01

The Ka-Band Object Observation and Monitoring, or KaBOOM, project is designed mainly to track and characterize near Earth objects. However, a smaller goal of the project would be to monitor pulsars and study their radio frequency signals for use as a clock in interstellar travel. The use of pulsars and their timing accuracy has been studied for decades, but never in the Ka-band of the radio frequency spectrum. In order to begin the use of KaBOOM for this research, the control systems need to be analyzed to ensure its capability. Flaws in the control documentation leave it unclear as to whether the control software processes coordinates from the J200 epoch. This experiment will examine the control software of the Intertronic 12m antennas used for the KaBOOM project and detail its capabilities in its "equatorial mode." The antennas will be pointed at 4 chosen points in the sky on several days while probing the virtual azimuth and elevation (horizon coordinate) registers. The input right ascension and declination coordinates will then be converted separately from the control software to horizontal coordinates and compared, thus determining the ability of the control software to process equatorial coordinates.

Dermatoglyphic patterns in dementia of the Alzheimer type: a case-control study.

PubMed Central

Berr, C; Okra-Podrabinek, N; Feteanu, D; Taurand, S; Hervy, M P; Forette, F; Piette, F; Sebag-Lanoe, R; Alperovitch, A

1992-01-01

STUDY OBJECTIVE--The aim was to compare digital and palmar dermatoglyphics in subjects with dementia of Alzheimer type and in mentally healthy elderly controls. DESIGN--This design was a case-control study. SETTING--The study was carried out in geriatric units and retirement communities in the Paris area. PARTICIPANTS--Cases were women with clinically diagnosed Alzheimer type dementia according to DSM III-R criteria (n = 82), mainly with late onset of the disease. Controls were women aged 85 years or older without cognitive deterioration (n = 76). MEASUREMENTS AND MAIN RESULTS--Finger and palm prints obtained from both hands by the classical ink method were examined. Fingerprints were classified into four types of figures. On palms, palmar flexion creases, palmar axial triradii, true patterns of the hypothenar area, and main line terminations were described. Examinations were performed by two examiners blind to the subjects's diagnostic category. For the different patterns studied, no major differences between dementia patients and elderly controls were found. Nor was there evidence of high frequencies of features commonly observed in Down's syndrome (trisomy 21), which have previously, though sporadically, been reported. CONCLUSIONS--On one of the largest samples of Alzheimer dementia patients studied, and with evaluation blind to diagnosis, no evidence has been found that particular dermatoglyphic patterns occur like those observed in Down's syndrome, a disease which is related to dementia of the Alzheimer type. PMID:1479321

Transmission-blocking activity is determined by transmission-reducing activity and number of control oocysts in Plasmodium falciparum standard membrane-feeding assay.

PubMed

Miura, Kazutoyo; Swihart, Bruce J; Deng, Bingbing; Zhou, Luwen; Pham, Thao P; Diouf, Ababacar; Burton, Timothy; Fay, Michael P; Long, Carole A

2016-07-29

Malaria transmission-blocking vaccines (TBVs) are potentially helpful tools for malaria eradication. The standard membrane-feeding assay (SMFA) is considered one of the "gold standard" assays for TBV development. However, lack of consensus in reporting results from SMFA has made it very challenging to compare results from different studies. Two main readouts, % inhibition in mean oocyst count per mosquito (TRA) and % inhibition in prevalence of infected mosquitoes (TBA), have been used widely. In this study, we statistically modeled the oocyst data in SMFA using data from 105 independent feeding experiments including 9804 mosquitoes. The model was validated using an independent data set that included 10,790 mosquitoes from 110 feeding studies. The model delineates a relationship between TRA, the mean oocyst count in the control mosquitoes (mo-contl), and TBA. While TRA was independent from mo-contl, TBA values changed depending on mo-contl. Regardless of monoclonal or polyclonal antibodies tested, there were strong concordances between observed TBA and predicted TBA based on the model using mo-contl and observed TRA. Simulations showed that SMFA with lower true control means had increased uncertainty in TRA estimates. The strong linkage between TBA, TRA and mo-contl inspired creation of a standardized TBA, a model-based TBA standardized to a target control mean, which allows comparison across multiple feeds regardless of mo-contl. This is the first study showing that the observed TBA can be reasonably predicted by mo-contl and the TRA of the test antibody using independent experimental data. This study indicates that TRA should be used to compare results from multiple feeds with different levels of mo-contl. If a measure of TBA is desired, it is better to report standardized TBA rather than observed TBA. These recommendations support rational comparisons of results from different studies, thus benefiting future TBV development. Published by Elsevier Ltd.

Transmission-blocking activity is determined by transmission-reducing activity and number of control oocysts in Plasmodium falciparum standard membrane-feeding assay

PubMed Central

Deng, Bingbing; Zhou, Luwen; Pham, Thao P.; Diouf, Ababacar; Burton, Timothy; Fay, Michael P.; Long, Carole A.

2016-01-01

Malaria transmission-blocking vaccines (TBVs) are potentially helpful tools for malaria eradication. The standard membrane-feeding assay (SMFA) is considered one of the “gold standard” assays for TBV development. However, lack of consensus in reporting results from SMFA has made it very challenging to compare results from different studies. Two main readouts, % inhibition in mean oocyst count per mosquito (TRA) and % inhibition in prevalence of infected mosquitoes (TBA), have been used widely. In this study, we statistically modeled the oocyst data in SMFA using data from 105 independent feeding experiments including 9,804 mosquitoes. The model was validated using an independent data set that included 10,790 mosquitoes from 110 feeding studies. The model delineates a relationship between TRA, the mean oocyst count in the control mosquitoes (mo-contl), and TBA. While TRA was independent from mo-contl, TBA values changed depending on mo-contl. Regardless of monoclonal or polyclonal antibodies tested, there were strong concordances between observed TBA and predicted TBA based on the model using mo-contl and observed TRA. Simulations showed that SMFA with lower true control means had increased uncertainty in TRA estimates. The strong linkage between TBA, TRA and mo-contl inspired creation of a standardized TBA, a model-based TBA standardized to a target control mean, which allows comparison across multiple feeds regardless of mo-contl. This is the first study showing that the observed TBA can be reasonably predicted by mo-contl and the TRA of the test antibody using independent experimental data. This study indicates that TRA should be used to compare results from multiple feeds with different levels of mo-contl. If a measure of TBA is desired, it is better to report standardized TBA rather than observed TBA. These recommendations support rational comparisons of results from different studies, thus benefiting future TBV development. PMID:27372156

Synthesis Study on Transitions in Signal Infrastructure and Control Algorithms for Connected and Automated Transportation

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

Aziz, H. M. Abdul; Wang, Hong; Young, Stan

Documenting existing state of practice is an initial step in developing future control infrastructure to be co-deployed for heterogeneous mix of connected and automated vehicles with human drivers while leveraging benefits to safety, congestion, and energy. With advances in information technology and extensive deployment of connected and automated vehicle technology anticipated over the coming decades, cities globally are making efforts to plan and prepare for these transitions. CAVs not only offer opportunities to improve transportation systems through enhanced safety and efficient operations of vehicles. There are also significant needs in terms of exploring how best to leverage vehicle-to-vehicle (V2V) technology,more » vehicle-to-infrastructure (V2I) technology and vehicle-to-everything (V2X) technology. Both Connected Vehicle (CV) and Connected and Automated Vehicle (CAV) paradigms feature bi-directional connectivity and share similar applications in terms of signal control algorithm and infrastructure implementation. The discussion in our synthesis study assumes the CAV/CV context where connectivity exists with or without automated vehicles. Our synthesis study explores the current state of signal control algorithms and infrastructure, reports the completed and newly proposed CV/CAV deployment studies regarding signal control schemes, reviews the deployment costs for CAV/AV signal infrastructure, and concludes with a discussion on the opportunities such as detector free signal control schemes and dynamic performance management for intersections, and challenges such as dependency on market adaptation and the need to build a fault-tolerant signal system deployment in a CAV/CV environment. The study will serve as an initial critical assessment of existing signal control infrastructure (devices, control instruments, and firmware) and control schemes (actuated, adaptive, and coordinated-green wave). Also, the report will help to identify the future needs for the signal infrastructure to act as the nervous system for urban transportation networks, providing not only signaling, but also observability, surveillance, and measurement capacity. The discussion of the opportunities space includes network optimization and control theory perspectives, and the current states of observability for key system parameters (what can be detected, how frequently can it be reported) as well as controllability of dynamic parameters (this includes adjusting not only the signal phase and timing, but also the ability to alter vehicle trajectories through information or direct control). The perspective of observability and controllability of the dynamic systems provides an appropriate lens to discuss future directions as CAV/CV become more prevalent in the future.« less

The in vivo trypanocidal effect of the diterpene 5-epi-icetexone obtained from Salvia gilliesii.

PubMed

Lozano, E; Strauss, M; Spina, R; Cifuente, D; Tonn, C; Rivarola, H W; Sosa, M A

2016-02-01

The search for new compounds with trypanocidal activity is crucial for the treatment of Chagas' disease. Previous in vitro studies have shown that the diterpene 5-epi-icetexone (ICTX) is active against Trypanosoma cruzi. The aim of this work was to evaluate the effect of ICTX on the parasites in infected mice, in an experimental model that mimics the acute phase of the disease. Swiss albino mice were infected with T. cruzi and treated daily with 10mg/kg/day ICTX (i.p.). Infected mice and mice injected with either saline or the vehicle DMSO were used as controls. Animals' survival and parasitemia were monitored once a week and histological studies were made at necropsy by the 5th week after infection. It was observed that the administration of ICTX increased the survival of mice infected, and induced a significant decrease in the parasitemia, as compared to controls. A similar protective effect was observed when animals were treated orally with benznidazole (BZN, used as a control of antiparasitic effect). By the 5th week post-infection, the presence of amastigote nests was observed within the fibers of the cardiac and skeletal muscle in controls, but not in animals treated with either ICTX or BZN. In addition, inflammatory infiltrates were observed in the tissues of controls, but not in animals treated with the drugs. We conclude that ICTX has an antiparasitic effect against T. cruzi, thus constituting an interesting option for the treatment of Chagas' disease, alone or combined with other drugs. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Herd effect from influenza vaccination in non-healthcare settings: a systematic review of randomised controlled trials and observational studies

PubMed Central

Mertz, Dominik; Fadel, Shaza A.; Lam, Po-Po; Tran, Dat; Srigley, Jocelyn A; Asner, Sandra A; Science, Michelle; Kuster, Stefan P; Nemeth, Johannes; Johnstone, Jennie; Ortiz, Justin R; Loeb, Mark

2016-01-01

Influenza vaccination programmes are assumed to have a herd effect and protect contacts of vaccinated persons from influenza virus infection. We searched MEDLINE, EMBASE, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), Global Health and the Cochrane Central Register of Controlled Trials (CENTRAL) from inception to March 2014 for studies assessing the protective effect of influenza vaccination vs no vaccination on influenza virus infections in contacts. We calculated odds ratios (ORs) and 95% confidence intervals (CIs) using a random-effects model. Of 43,082 screened articles, nine randomised controlled trials (RCTs) and four observational studies were eligible. Among the RCTs, no statistically significant herd effect on the occurrence of influenza in contacts could be found (OR: 0.62; 95% CI: 0.34–1.12). The one RCT conducted in a community setting, however, showed a significant effect (OR: 0.39; 95% CI: 0.26–0.57), as did the observational studies (OR: 0.57; 95% CI: 0.43–0.77). We found only a few studies that quantified the herd effect of vaccination, all studies except one were conducted in children, and the overall evidence was graded as low. The evidence is too limited to conclude in what setting(s) a herd effect may or may not be achieved. PMID:27784531

Rejecting salient distractors: Generalization from experience.

PubMed

Vatterott, Daniel B; Mozer, Michael C; Vecera, Shaun P

2018-02-01

Distraction impairs performance of many important, everyday tasks. Attentional control limits distraction by preferentially selecting important items for limited-capacity cognitive operations. Research in attentional control has typically investigated the degree to which selection of items is stimulus-driven versus goal-driven. Recent work finds that when observers initially learn a task, the selection is based on stimulus-driven factors, but through experience, goal-driven factors have an increasing influence. The modulation of selection by goals has been studied within the paradigm of learned distractor rejection, in which experience over a sequence of trials enables individuals eventually to ignore a perceptually salient distractor. The experiments presented examine whether observers can generalize learned distractor rejection to novel distractors. Observers searched for a target and ignored a salient color-singleton distractor that appeared in half of the trials. In Experiment 1, observers who learned distractor rejection in a variable environment rejected a novel distractor more effectively than observers who learned distractor rejection in a less variable, homogeneous environment, demonstrating that variable, heterogeneous stimulus environments encourage generalizable learned distractor rejection. Experiments 2 and 3 investigated the time course of learned distractor rejection across the experiment and found that after experiencing four color-singleton distractors in different blocks, observers could effectively reject subsequent novel color-singleton distractors. These results suggest that the optimization of attentional control to the task environment can be interpreted as a form of learning, demonstrating experience's critical role in attentional control.

Association between metabolic control and oral health in adolescents with type 1 diabetes mellitus.

PubMed

Saes Busato, Ivana Maria; Bittencourt, Mônica Sommer; Machado, Maria Angela Naval; Grégio, Ana Maria Trindade; Azevedo-Alanis, Luciana Reis

2010-03-01

The aim of this study was to evaluate the association between metabolic control and oral health of adolescents with type 1 diabetes mellitus (DM1). A case-control epidemiologic study was performed on adolescents allocated between 2 groups: DM1 group composed of 51 with DM1, and control group composed of 51 without diabetes. In the DM1 group, metabolic control data were observed (glycosylated hemoglobin (GHb) and capillary glucose), whereby GHb < or =8.0% was considered to indicate good metabolic control (DM1-A) and >8.0% poor metabolic control (DM1-B). Oral mucosal abnormalites, Community Periodontal Index (CPI), and decayed, missing, and filled (DMF) index were documented. Salivary flow was evaluated by means of stimulated saliva collection (SSFR). Glycosylated hemoglobin values of < or =8.0% (DM1-A) were observed in 17 (24%) and >8.0% (DM1-B) in 34 (76%) of the subjects. The average DMF indexes were 1.5 (control) and 3.3 (DM1-group) (P < or = .05). The average CPIs were 0.2 (control), 1.4 (DM1-A), and 2.0 (DM1-B) (P < or = .05). Average SSFRs were 0.997 (DM1-A), 0.903 (DM1-B), and 1.224 (control) mL/min. Oral health of adolescents with DM1 was impaired regardless of metabolic control. Copyright 2010 Mosby, Inc. All rights reserved.

Kinesitherapy alleviates fatigue in terminal hospice cancer patients-an experimental, controlled study.

PubMed

Buss, Tomasz; de Walden-Gałuszko, Krystyna; Modlińska, Aleksandra; Osowicka, Magdalena; Lichodziejewska-Niemierko, Monika; Janiszewska, Justyna

2010-06-01

The study was focused on the influence of the kinesitherapy on fatigue and the quality of life in the terminal hospice cancer patients. Forty-nine patients were included into the study and divided into experimental group A (with kinesitherapy) with 30 subjects and control group B (without kinesitherapy) with 19 subjects. Patients from group A did the exercises three times a week, for 20-30 min, for the period of 3-4 weeks. The exercises were individually supervised by a physiotherapist, following a carefully worked out pattern. In both groups, the changes in the intensity of fatigue and the quality of life were observed by means of using Rotterdam symptom checklist, brief fatigue inventory, and visual analogue fatigue scale. In group A, the intensity of fatigue decreased significantly after 3 weeks of kinesitherapy. In group B, fatigue deteriorated significantly in comparison with the initial measurement. The intensity of physical symptoms in group A decreased significantly after 2 weeks of kinesitherapy, whereas in group B, increased after 2 weeks of observation. The quality of life in group A remained stable throughout the study. A tendency towards the deterioration of the quality of life with the time passing in group B was noticeable. Our analysis showed that, on average, after 3 weeks of kinesitherapy, a significant decrease of the intensity of fatigue was observed, while in the control group, it increased after 2 weeks of observation. The obtained results provide evidence that a planned set of exercises decreases cancer-related fatigue effectively.

Selenium and Preeclampsia: a Systematic Review and Meta-analysis.

PubMed

Xu, Min; Guo, Dan; Gu, Hao; Zhang, Li; Lv, Shuyan

2016-06-01

Conflicting results exist between selenium concentration and preeclampsia. The role of selenium in the development of preeclampsia is unclear. We conducted a meta-analysis to compare the blood selenium level in patients with preeclampsia and healthy pregnant women, and to determine the effectiveness of selenium supplementation in preventing preeclampsia. We searched PubMed, ScienceDirect, the Cochrane Library, and relevant references for English language literature up to November 25, 2014. Mean difference from observational studies and relative risk from randomized controlled trials were meta-analyzed by a random-effect model. Thirteen observational studies with 1515 participants and 3 randomized controlled trials with 439 participants were included in the meta-analysis. Using a random-effect model, a statistically significant difference in blood selenium concentration of -6.47 μg/l (95 % confidence interval (CI) -11.24 to -1.7, p = 0.008) was seen after comparing the mean difference of observational studies. In randomized controlled trials, using a random-effect model, the relative risk for preeclampsia was 0.28 (0.09 to 0.84) for selenium supplementation (p = 0.02). Evidence from observational studies indicates an inverse association of blood selenium level and the risk of preeclampsia. Supplementation with selenium significantly reduces the incidence of preeclampsia. However, more prospective clinical trials are required to assess the association between selenium supplementation and preeclampsia and to determine the dose, beginning time, and duration of selenium supplementation.

Captopril as a replacement for multiple therapy in hypertension: a controlled study.

PubMed

Yodfat, Y; Fidel, J; Bloom, D S

1985-11-01

A controlled study was conducted in hypertensive patients to investigate whether captopril can be substituted for the various other antihypertensive drugs (not including diuretics) to reduce side effects and improve the quality of life. Captopril in a twice daily dose of 25-50 mg, was substituted and titrated in 54 patients. Fifty-two patients, matched by age and sex, comprised the control group, and were treated with a variety of agents. During a follow-up of 9 months, 44 of the patients receiving captopril (81%) achieved the goal of supine blood pressure less than 90 mmHg. Captopril was discontinued in two patients due to side effects. Mild proteinuria was observed in two patients. A significant reduction in scores or rates of side effects (numbness, blurred vision, insomnia, vivid dreams, cold extremities, sleepiness, sexual dysfunction and fatigue) and improvement in quality of life (general feeling, mood and concentration) was observed in the study group compared with the control group. Captopril alone in a twice daily dose of 25-50 mg, or in co-treatment with thiazide, provided sustained blood pressure control with minimal side effects and improvement in quality of life compared with the treatment of hypertension with beta-blockers, vasodilators or methyldopa.

A Case for Less Intensive Blood Pressure Control: It Matters to Achieve Target Blood Pressure Early and Sustained Below 140/90mmHg.

PubMed

Mariampillai, Julian E; Eskås, Per Anders; Heimark, Sondre; Kjeldsen, Sverre E; Narkiewicz, Krzysztof; Mancia, Giuseppe

Although high blood pressure (BP) is the leading risk factors for cardiovascular (CV) disease, the optimal BP treatment target in order to reduce CV risk is unclear in the aftermath of the SPRINT study. The aim of this review is to assess large, randomized, and controlled trials on BP targets, as well as review selected observational analyses from other large randomized BP trials in order to evaluate the benefit of intense vs. standard BP control. None of the studies, except SPRINT, favored intense BP treatment. Some of the studies suggested favorable effects of lowering treatment target in patients with diabetes or high risk of stroke. In SPRINT, a new BP measurement method was introduced, and the results must be interpreted in light of this. The results of the observational analyses indicated the best preventive effect when achieving early and sustained BP control rather than low targets. In conclusion, today's guidelines' recommended treatment target of <140/90mmHg seems sufficient for most patients. Early and sustained BP control should be the main focus. Copyright © 2016 Elsevier Inc. All rights reserved.

Reduced Burden of Salmonella enterica in Bovine Subiliac Lymph Nodes Associated with Administration of a Direct-fed Microbial.

PubMed

Vipham, J L; Loneragan, G H; Guillen, L M; Brooks, J C; Johnson, B J; Pond, A; Pond, N; Brashears, M M

2015-12-01

Despite effective food safety interventions within abattoirs, Salmonella enterica remains a common contaminant of raw ground beef. Research has recently implicated peripheral lymph nodes (PLNs) as a potential route by which Salmonella contaminates ground beef. This study examined the efficacy of using Lactobacillus animalis (formerly designated Lactobacillus acidophilus; NP51) and Propionibacterium freudenreichii (NP24), at 10(9) cfu/head/day, as a direct-fed microbial (DFM) in feedlot cattle diets to control Salmonella within PLNs. Two studies were conducted in which cattle were randomly allocated into either control or DFM treatment groups. Diets of treated cattle were supplemented with 10(9) cfu/head/day of the DFM, while control groups received no DFM supplementation. During slaughter at abattoirs, one subiliac lymph node (SLN) per carcass was collected from 627 carcasses from one study and 99 carcasses from the second study. Lymph nodes were cultured to estimate the presence and concentration of Salmonella. In the first study, effects of DFM supplementation varied across slaughter days. On the first and second slaughter days, prevalence was reduced by 50% (P = 0.0072) and 31% (P = 0.0093), respectively. No significant difference was observed on slaughter day three (P = 0.1766). In the second study, Salmonella was 82% less likely (P = 0.008) to be recovered from SLNs of treatment cattle. While a greater relative risk reduction was observed in the latter study, absolute risk reductions were similar across studies. A significant reduction in the concentration of Salmonella in SLNs (P < 0.0001) on a cfu/g and cfu/node basis was also observed in cattle administered NP51 and NP24 in the first study; in the second study, too few quantifiable SLNs were observed to facilitate meaningful comparisons. The results indicate that NP51 and NP24 supplementation may aid in reducing the prevalence and concentration of Salmonella in SLNs and, therefore, serve as an effective control measure to reduce Salmonella in ground beef products. © 2015 Blackwell Verlag GmbH.

The use of temperature programmable flow tubes for the study of atmospheric aerosols

NASA Astrophysics Data System (ADS)

Khalizov, A.; Sloan, J. J.

2003-04-01

In order to understand the response of atmospheric aerosols to changes they encounter in the natural atmosphere, it is usually necessary to observe models of these aerosol systems under carefully controlled laboratory conditions. This is particularly difficult for the condensed phase, for which agglomeration, gas-particle exchange and gravitational settling affect the composition and limit the observation time. Traditionally, studies of this kind have been carried out in large static chambers and flow tubes. While large chambers provide relatively long observations times, they afford the experimenter less direct control over the environment of the particles. Flow tubes, on the other hand provide very precise control of the experimental conditions, but a much shorter contact time. We have used temperature programmable flow tubes for the past decade to study the composition, size and phase changes that occur when aerosols are exposed to variations in the temperature and composition of the surrounding atmosphere. In many cases, our measurements also yield accurate rate constants for the nucleation of solids in liquid droplets. In this presentation, we will illustrate the capabilities of this method using results obtained from a new temperature programmable flow tube recently built in our laboratory.

Genotoxic Evaluation of Mexican Welders Occupationally Exposed to Welding-Fumes Using the Micronucleus Test on Exfoliated Oral Mucosa Cells: A Cross-Sectional, Case-Control Study

PubMed Central

Jara-Ettinger, Ana Cecilia; López-Tavera, Juan Carlos; Zavala-Cerna, María Guadalupe; Torres-Bugarín, Olivia

2015-01-01

Background An estimated 800,000 people worldwide are occupationally exposed to welding-fumes. Previous studies show that the exposure to such fumes is associated with damage to genetic material and increased cancer risk. In this study, we evaluate the genotoxic effect of welding-fumes using the Micronucleus Test on oral mucosa cells of Mexican welders. Material and Methods We conducted a cross-sectional, matched case-control study of n = 66 (33 exposed welders, and 33 healthy controls). Buccal mucosa smears were collected and stained with acridine orange, observed under 100x optical amplification with a fluorescence lamp, and a single-blinded observer counted the number of micronuclei and other nuclear abnormalities per 2,000 observed cells. We compared the frequencies of micronuclei and other nuclear abnormalities, and fitted generalised linear models to investigate the interactions between nuclear abnormalities and the exposure to welding-fumes, while controlling for smoking and age. Results Binucleated cells and condensed-chromatin cells showed statistically significant differences between cases and controls. The frequency of micronuclei and the rest of nuclear abnormalities (lobed-nuclei, pyknosis, karyolysis, and karyorrhexis) did not differ significantly between the groups. After adjusting for smoking, the regression results showed that the occurrence of binucleated cells could be predicted by the exposure to welding-fumes plus the presence of tobacco consumption; for the condensed-chromatin cells, our model showed that the exposure to welding-fumes is the only reliable predictor. Conclusions Our findings suggest that Mexican welders who are occupationally exposed to welding-fumes have increased counts of binucleated and condensed-chromatin cells. Nevertheless, the frequencies of micronuclei and the rest of nuclear abnormalities did not differ between cases and controls. Further studies should shed more light on this subject. PMID:26244938

Zero-gravity cloud physics laboratory: Candidate experiments definition and preliminary concept studies

NASA Technical Reports Server (NTRS)

Eaton, L. R.; Greco, R. V.; Hollinden, A. B.

1973-01-01

The candidate definition studies on the zero-g cloud physics laboratory are covered. This laboratory will be an independent self-contained shuttle sortie payload. Several critical technology areas have been identified and studied to assure proper consideration in terms of engineering requirements for the final design. Areas include chambers, gas and particle generators, environmental controls, motion controls, change controls, observational techniques, and composition controls. This unique laboratory will allow studies to be performed without mechanical, aerodynamics, electrical, or other type techniques to support the object under study. This report also covers the candidate experiment definitions, chambers and experiment classes, laboratory concepts and plans, special supporting studies, early flight opportunities and payload planning data for overall shuttle payload requirements assessments.

40 CFR 799.9365 - TSCA combined repeated dose toxicity study with the reproduction/developmental toxicity screening...

Code of Federal Regulations, 2011 CFR

2011-07-01

... the control and the top dose group for observation of reversibility, persistence or delayed occurrence... toxicity. (2) Dosage. (i) Generally, at least three test groups and a control group should be used. If... administering the test substance, the control group should receive the vehicle in the highest volume used. (ii...

40 CFR 799.9365 - TSCA combined repeated dose toxicity study with the reproduction/developmental toxicity screening...

Code of Federal Regulations, 2012 CFR

2012-07-01

... the control and the top dose group for observation of reversibility, persistence or delayed occurrence... toxicity. (2) Dosage. (i) Generally, at least three test groups and a control group should be used. If... administering the test substance, the control group should receive the vehicle in the highest volume used. (ii...

40 CFR 799.9365 - TSCA combined repeated dose toxicity study with the reproduction/developmental toxicity screening...

Code of Federal Regulations, 2010 CFR

2010-07-01

... the control and the top dose group for observation of reversibility, persistence or delayed occurrence... toxicity. (2) Dosage. (i) Generally, at least three test groups and a control group should be used. If... administering the test substance, the control group should receive the vehicle in the highest volume used. (ii...

40 CFR 799.9365 - TSCA combined repeated dose toxicity study with the reproduction/developmental toxicity screening...

Code of Federal Regulations, 2013 CFR

2013-07-01

... the control and the top dose group for observation of reversibility, persistence or delayed occurrence... toxicity. (2) Dosage. (i) Generally, at least three test groups and a control group should be used. If... administering the test substance, the control group should receive the vehicle in the highest volume used. (ii...

40 CFR 799.9365 - TSCA combined repeated dose toxicity study with the reproduction/developmental toxicity screening...

Code of Federal Regulations, 2014 CFR

2014-07-01

... the control and the top dose group for observation of reversibility, persistence or delayed occurrence... toxicity. (2) Dosage. (i) Generally, at least three test groups and a control group should be used. If... administering the test substance, the control group should receive the vehicle in the highest volume used. (ii...

Radiation Hazards

DTIC Science & Technology

1975-08-01

memory difficulties. Psychic changes that include unstable mood, hypochondriasis, and anxiety have been observed. Compared to those in control groups ...and extrapyremidal motor systems. The incidence of neurosis was significantly higher than in controls . Experimental physiologic and EEG methods...differentiated from those in the control group and consequently could not be related to their microwave exposure (13). In a study reported by Czerski and

Maternal Over-Control Moderates the Association between Early Childhood Behavioral Inhibition and Adolescent Social Anxiety Symptoms

ERIC Educational Resources Information Center

Lewis-Morrarty, Erin; Degnan, Kathryn A.; Chronis-Tuscano, Andrea; Rubin, Kenneth H.; Cheah, Charissa S. L.; Pine, Daniel S.; Henderon, Heather A.; Fox, Nathan A.

2012-01-01

Behavioral inhibition (BI) and maternal over-control are early risk factors for later childhood internalizing problems, particularly social anxiety disorder (SAD). Consistently high BI across childhood appears to confer risk for the onset of SAD by adolescence. However, no prior studies have prospectively examined observed maternal over-control as…

Robust iterative learning contouring controller with disturbance observer for machine tool feed drives.

PubMed

Simba, Kenneth Renny; Bui, Ba Dinh; Msukwa, Mathew Renny; Uchiyama, Naoki

2018-04-01

In feed drive systems, particularly machine tools, a contour error is more significant than the individual axial tracking errors from the view point of enhancing precision in manufacturing and production systems. The contour error must be within the permissible tolerance of given products. In machining complex or sharp-corner products, large contour errors occur mainly owing to discontinuous trajectories and the existence of nonlinear uncertainties. Therefore, it is indispensable to design robust controllers that can enhance the tracking ability of feed drive systems. In this study, an iterative learning contouring controller consisting of a classical Proportional-Derivative (PD) controller and disturbance observer is proposed. The proposed controller was evaluated experimentally by using a typical sharp-corner trajectory, and its performance was compared with that of conventional controllers. The results revealed that the maximum contour error can be reduced by about 37% on average. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

Occupational risk factors for testicular cancer: a registry-based case-control study in Rhineland Palatinate – Germany

PubMed Central

Yousif, Lamyaa; Hammer, Gaël P.; Emrich, Katharina; Blettner, Maria; Zeeb, Hajo

2013-01-01

Objectives: Testicular cancer affects mainly men below the age of 50. An association with occupation and social status has been suggested but risk factors are not well understood. A registry-based case-control study focusing on occupation was performed in Germany. Methods: All 348 testicular cancer cases with available gainful occupational information registered between 2000 and 2005; as well as 564 suitable controls (from a pool of other cancers) were drawn from the Cancer Registry of Rhineland-Palatinate. Unconditional logistic regression was used to compute odds ratios (OR) and associated 95% confidence intervals (CI). Results: Slightly elevated OR were observed for technicians and related professionals (OR 1.62, 95% CI 1.00–2.63) and for clerical support workers (OR 1.71, 95% CI 1.14–2.56). This increase was highest in the age group 20–50 for technicians (OR 2.02, 95% CI 1.23–3.33) and clerks (OR 2.00, 95% CI 1.30–3.09), respectively. An association with testicular cancer was observed for no other occupation. Conclusion: An increased risk of testicular cancer was observed for technicians and related professionals and clerical support workers. This could be related to socioeconomic status or sedentary life style, two factors that were identified in previous studies. While the feasibility of a purely registry-based study was shown, missing occupational data and the choice of cancer controls represent challenges to the validity of this approach. PMID:24265602

[Adaptation of the Hinting Task theory of the mind test to Spanish].

PubMed

Gil, David; Fernández-Modamio, Mar; Bengochea, Rosario; Arrieta, Marta

2012-01-01

Many studies have found that patients with schizophrenia have a deficit in theory of mind. Some authors associate this deficit with the presence of symptoms, while others maintain that it can also be observed in patients in the remission phase. There is no reference test to assess theory of mind in schizophrenia, although one of the most used is the Hinting Task. The aim of the present study consists of adapting and validating, in Spanish, the 10 histories that make up this test. The study was conducted on a sample of 39 control subjects and 40 patients with schizophrenia. The internal consistency and the between-observer reliability and test-retest were assessed in both sample groups. The performance of the patients and control subjects were also compared. Good reliability data was obtained in the inter-observer and test-retest in the two samples. On the other hand, the internal consistency was somewhat low for all of the 10 histories. For this reason, and starting from a previous study, a reduced version of 5 histories was prepared, which showed good internal consistency. The patients with schizophrenia obtained a significantly lower score than the control subjects in 8 out of the 10 histories. The reduced Spanish version of the Hinting Task demonstrated good psychometric properties. When compared to the control group, the patients with schizophrenia had a deficit in theory of mind. Copyright © 2011 SEP y SEPB. Published by Elsevier Espana. All rights reserved.

The effect of learner's control of self-observation strategies on learning of front crawl.

PubMed

Marques, Priscila Garcia; Corrêa, Umberto Cesar

2016-02-01

This study investigated the effect of learner's control of self-observation strategies on motor skill learning. For this purpose, beginner and intermediate learner swimmers practised the front crawl. Seventy college students took part in this experiment. They comprised 40 novice learners, both male (n=19) and female (n=21), with an average age of 20.7 years (±0.44), and 30 intermediate learners, both male (n=17) and female (n=13), with an average age of 21.1 years (±0.86). The design involved a pretest (one day), four acquisition sessions (four days), and a retention test (one day). They were divided into three groups: (1) choice, which could choose to watch a video with their best or overall performance during practise; (2) yoked, which were paired to those of the choice group; and (3) control (did not watch any video). The measures included the performance of front crawl and self-efficacy. The results showed that: (1) beginners who chose a type of observation strategy had superior motor skill learning; (2) for intermediate learners, self-observation promoted better motor learning, regardless of the control of choices; (3) self-observation improved self-efficacy beliefs. Copyright © 2016 Elsevier B.V. All rights reserved.

Assessment of Clinical Effect of Perioperative Comprehensive Nursing Intervention Pattern in 23G Minimally Invasive Vitreous Surgery.

PubMed

Shen, Jie; Li, Su-Yan; Wang, Jian-Yu; Chen, Jing; Wang, Wen

2016-01-01

We observed the clinical effects of comprehensive nursing intervention pattern in 23G minimally invasive vitreous surgery according to the comprehensive nursing intervention table developed by our hospital, which would supply a basis for its clinical application. In this prospective study, we followed 120 patients undergoing 23G minimally invasive vitreous surgery from Xuzhou First People's Hospital from February 2013 to February 2015 and divided them into control and observation groups by a random number table (60 patients in each group). A regular nursing pattern was adopted for the control group, and a comprehensive nursing intervention pattern was adopted for the observation group. After that, a comparative analysis was made to identify the differences between the clinical effects of the two groups. Scores of cognition ratio, patient compliance and comfort level of patients in the observation group were higher than those of the control group were, and there was significant difference between the groups (P< 0.05). Complication incidence of the observation group is significantly lower than that of the control group (P<0.05). The comprehensive nursing intervention pattern developed by our hospital can improve clinical effects notably, which is of application value .We recommend it to be applied in eye diseases.

Effect of cognitive and motor tasks on postural stability in Parkinson's disease: a posturographic study.

PubMed

Marchese, Roberta; Bove, Marco; Abbruzzese, Giovanni

2003-06-01

To analyse the effect of concomitant cognitive or motor task performance on balance control in Parkinson's disease (PD), we performed a posturographic study in 24 PD patients and in 20 sex- and age-matched control subjects. Postural sway was measured with eyes open (EO) and eyes closed (EC) during quiet stance and during performance of calculation or motor sequence of thumb opposition to the other fingers. No difference of centre of foot pressure (COP) parameters was observed during quiet standing (either EO or EC) between patients and controls, but visual deprivation induced in both groups a worsening of postural stability. COP area was significantly increased in PD patients during dual task performance, whereas no difference of COP path and x-y axes was observed. The effects induced by the performance of cognitive or motor task were significantly more evident in PD patients with clinical evidence of postural instability (presence of prior falls in the history). This study demonstrates that dual task interference on postural control can be observed in PD patients during performance of cognitive as well as motor tasks. The balance deterioration during dual task performance was significantly enhanced in patients with history of prior falls. These findings have some implications for the strategies to be used in reducing the risk of fall in PD. Copyright 2003 Movement Disorder Society

Evaluation of respiratory dynamics by volumetric capnography during submaximal exercise protocol of six minutes on treadmill in cystic fibrosis patients.

PubMed

Parazzi, Paloma L F; Marson, Fernando A L; Ribeiro, Maria A G O; Schivinski, Camila I S; Ribeiro, José D

2017-11-29

Volumetric capnography provides the standard CO 2 elimination by the volume expired per respiratory cycle and is a measure to assess pulmonary involvement. Thus, the objective of this study was to evaluate the respiratory dynamics of healthy control subjects and those with cystic fibrosis in a submaximal exercise protocol for six minutes on the treadmill, using volumetric capnography parameters (slope 3 [Slp3], Slp3/tidal volume [Slp3/TV], and slope 2 [Slp2]). This was a cross-sectional study with 128 subjects (cystic fibrosis, 64 subjects; controls, 64 subjects]. Participants underwent volumetric capnography before, during, and after six minutes on the treadmill. Statistical analysis was performed using the Friedman, Mann-Whitney, and Kruskal-Wallis tests, considering age and sex. An alpha=0.05 was considered. Six minutes on the treadmill evaluation: in cystic fibrosis, volumetric capnography parameters were different before, during, and after six minutes on the treadmill; the same was observed for the controls, except for Slp2. Regarding age, an Slp3 difference was observed in cystic fibrosis patients regardless of age, at all moments, and in controls for age≥12 years; a difference in Slp3/TV was observed in cystic fibrosis and controls, regardless of age; and an Slp2 difference in the cystic fibrosis, regardless of age. Regarding sex, Slp3 and Slp3/TV differences were observed in cystic fibrosis regardless of sex, and in controls in male participants; an Slp2 difference was observed in the cystic fibrosis and female participants. The analysis between groups (cystic fibrosis and controls) indicated that Slp3 and Slp3/TV has identified the CF, regardless of age and sex, while the Slp2 showed the CF considering age. Cystic fibrosis showed greater values of the parameters before, during, and after exercise, even when stratified by age and sex, which may indicate ventilation inhomogeneity in the peripheral pathways in the cystic fibrosis. Copyright © 2017 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

Psoriasis increases risk of new-onset atrial fibrillation: a systematic review and meta-analysis of prospective observational studies.

PubMed

Upala, Sikarin; Shahnawaz, Afeefa; Sanguankeo, Anawin

2017-08-01

Psoriasis is a common chronic immune-mediated dermatological disease that increases the risk of cardiovascular disease. We conducted a systematic review and meta-analysis to evaluate the association between psoriasis and atrial fibrillation from prospective observational studies. A comprehensive search of the databases of the MEDLINE and EMBASE was performed from inception through November 2015. The inclusion criterion was the prospective observational study that assessed the risk of new-onset atrial fibrillation in adults with psoriasis. Outcome was the adjusted hazard ratio (HR) of atrial fibrillation comparison between patients with psoriasis and controls. Pooled HR and 95% confidence intervals (CI) were calculated using a random-effects model. The initial search yielded 176 articles. Fifteen articles underwent full-length review and data were extracted from 4 observational studies. Incidence of atrial fibrillation was ascertained by cardiologist-reviewed electrocardiograms. There was a significant increased risk of new-onset atrial fibrillation in patients with psoriasis compared to controls with a pooled HR 1.42 (95%CI 1.22-1.65). Our meta-analysis of prospective studies demonstrated that patients with psoriasis have increased risk of new-onset atrial fibrillation. Future interventional studies addressing the impact of psoriasis treatment and prevention of atrial fibrillation should be performed.

Is There a Role for Oral or Intravenous Ascorbate (Vitamin C) in Treating Patients With Cancer? A Systematic Review

PubMed Central

Hutton, Brian; Ng, Terry; Shorr, Risa; Clemons, Mark

2015-01-01

Background. Many cancer patients receive supplemental ascorbate (vitamin C) in the belief that it synergizes the anticancer effects of chemotherapy and reduces its toxicity. Methods. A systematic review was performed to evaluate the antitumor effects and toxicity of ascorbate treatment. Medline (1946 to March 2014), EMBASE (1947 to March 2014), and the Cochrane central register (1993 to March 2014) were searched for randomized and observational studies. Results. Of 696 identified records, 61 full-text articles were screened and 34 were included. In total, 5 randomized controlled trials (RCTs) (n = 322), 12 phase I/II trials (n = 287), 6 observational studies (n = 7,599), and 11 case reports (n = 267) were identified. Because of study heterogeneity, no meta-analyses were performed. No RCTs reported any statistically significant improvements in overall or progression-free survival or reduced toxicity with ascorbate relative to control arm. Evidence for ascorbate’s antitumor effects was limited to case reports and observational and uncontrolled studies. Conclusion. There is no high-quality evidence to suggest that ascorbate supplementation in cancer patients either enhances the antitumor effects of chemotherapy or reduces its toxicity. Given the high financial and time costs to patients of this treatment, high-quality placebo-controlled trials are needed. PMID:25601965

Study design and hierarchy of evidence for surgical decision making.

PubMed

Sprague, Sheila; McKay, Paula; Thoma, Achilleas

2008-04-01

This article provides a historical overview of the hierarchy of evidence for surgical decision making and discusses key study designs in the hierarchy of evidence. This encompasses meta-analyses, randomized controlled trials, and observational studies, including cohort and case-controlled studies, case series and case reports, and basic science studies. This article also reviews the principles and importance of evidence-based plastic surgery and describes several systems to rate the strength of the scientific evidence.

Effects of reduced plantar cutaneous sensation on static postural control in individuals with and without chronic ankle instability.

PubMed

Song, Kyeongtak; Kang, Tae Kyu; Wikstrom, Erik A; Jun, Hyung-Pil; Lee, Sae Yong

2017-10-01

The purpose of this study was to determine how reduced plantar cutaneous sensation influences static postural control in individuals with and without CAI. A case-control study design. Twenty-six individuals with self-reported CAI and 26 matched healthy controls participated in this study. The plantar aspect of the participants' foot was then submersed in ice water (0°C) for 10min to reduce plantar sensation. Before and after the cooling procedure, plantar cutaneous sensation thresholds and single leg balance with eyes open and closed were assessed. Significantly, higher scores were observed in both groups after ice water submersion (p<0.001) indicating a significant reduction in the plantar cutaneous sensitivity after the cooling procedure. In single limb balance with eyes open, there were significant intervention main effects for the TTB ML mean (p<0.001), TTB AP mean (p=0.035) and TTB ML SD (p=0.021); indicating postural control improvement in both groups post-cooling. In single limb balance with eyes closed, Group×Intervention interactions were observed for the TTB AP mean (p=0.003) and TTB AP SD (p=0.017); indicating postural control deficits in CAI group post-cooling, but no changes in the control group. The main finding of this study was that reduced plantar cutaneous sensation induced by an ice submersion procedure caused eyes closed postural control impairments in those with CAI but not healthy controls. The present investigation demonstrated that the ability to dynamically reweight among sensory inputs to maintain postural stability appears to be diminished in CAI patients compared to healthy controls. Copyright © 2016. Published by Elsevier Ltd.

Effect of gamma radiation on Aspergillus flavus and Aspergillus ochraceus ultrastructure and mycotoxin production

NASA Astrophysics Data System (ADS)

Ribeiro, J.; Cavaglieri, L.; Vital, H.; Cristofolini, A.; Merkis, C.; Astoreca, A.; Orlando, J.; Carú, M.; Dalcero, A.; Rosa, C. A. R.

2011-05-01

The aim of this work was to study the effect of gamma radiation (2 kGy) on Aspergillus flavus and Aspergillus ochraceus ultrastructure. Moreover, the influence on aflatoxin B 1 and ochratoxin A production was also observed. Irradiated A. flavus strain showed a dull orangish colony while control strain showed the typical green color. Minor differences were observed on stipes, metulae and conidia size between control and irradiated A. flavus and A. ochraceus strains. Irradiated fungi showed ultrastructural changes on cell wall, plasmalema and cytoplasm levels. The levels of mycotoxins produced by irradiated strains were two times greater than those produced by control strains. Successive transferences of irradiated strains on malt extract agar allowed the fungus to recuperate morphological characteristics. Although minor changes in the fungal morphology were observed, ultrastructural changes at cell wall level and the increase of mycotoxin production ability were observed. Inappropriate storage of irradiated food and feed would allow the development of potentially more toxicogenic fungal propagules.

Associations of Mother's and Father's Parenting Practices with Children's Observed Social Reticence in a Competitive Situation: A Monozygotic Twin Difference Study

ERIC Educational Resources Information Center

Guimond, Fanny-Alexandra; Brendgen, Mara; Forget-Dubois, Nadine; Dionne, Ginette; Vitaro, Frank; Tremblay, Richard E.; Boivin, Michel

2012-01-01

This study used the monozygotic (MZ) twin difference method to examine whether the unique environmental effects of maternal and paternal overprotection and hostility at the age of 30 months predict twins' observed social reticence in a competitive situation in kindergarten, while controlling for the effect of family-wide influences, including…

[Observation of Attachment Disorder Symptoms in Middle Childhood].

PubMed

Iwanski, Alexandra; Zimmermann, Peter

2018-05-01

Observation of Attachment Disorder Symptoms in Middle Childhood Attachment in childhood is mainly assessed by observation. In contrast, assessment of attachment disorder symptoms (RAD) is mainly based on caregiver reports. The present study uses a newly developed observation tool (Coding of Attachment Disorder Behavior in Children; Iwanski u. Zimmermann, 2013) to assess attachment disorder symptoms in a group of school-aged children from a risk group for the development of attachment disorder symptoms and non-clinical controls. In addition, caregiver reports on RAD symptoms are also assessed (Relationship Problems Questionnaire; Minnis, Rabe-Hesketh, Wolkind, 2002; Disturbances of Attachment Interview; Smyke u. Zeanah, 1999). Moreover, associations with children's self-concept (Harter, 2012) were studied. Results reveal that children at risk showed more inhibited and disinhibited attachment disorder symptoms and a more negative self-concept compared to non-clinical controls. RAD symptoms are shown in interaction with both the caregiver and a stranger. The use of a reliable and valid observation tool for the diagnostic of attachment disorder symptoms besides ratings of caregivers is recommended for clinical practice and research.

Shock and Vibration Control of a Golf-Swing Robot at Impacting the Ball

NASA Astrophysics Data System (ADS)

Hoshino, Yohei; Kobayashi, Yukinori

A golf swing robot is a kind of fast motion manipulator with a flexible link. A robot manipulator is greatly affected by Corioli's and centrifugal forces during fast motion. Nonlinearity due to these forces can have an adverse effect on the performance of feedback control. In the same way, ordinary state observers of a linear system cannot accurately estimate the states of nonlinear systems. This paper uses a state observer that considers disturbances to improve the performance of state estimation and feedback control. A mathematical model of the golf robot is derived by Hamilton's principle. A linear quadratic regulator (LQR) that considers the vibration of the club shaft is used to stop the robot during the follow-through action. The state observer that considers disturbances estimates accurate state variables when the disturbances due to Corioli's and centrifugal forces, and impact forces work on the robot. As a result, the performance of the state feedback control is improved. The study compares the results of the numerical simulations with experimental results.

Attention-Related Eye Vergence Measured in Children with Attention Deficit Hyperactivity Disorder

PubMed Central

Solé Puig, Maria; Pérez Zapata, Laura; Puigcerver, Laura; Esperalba Iglesias, Neus; Sanchez Garcia, Carmen; Romeo, August; Cañete Crespillo, Josep; Supèr, Hans

2015-01-01

Recent evidence shows a novel role for eye vergence in orienting attention in adult subjects. Here we investigated whether such modulation in eye vergence by attention is present in children and whether it is altered in children with ADHD compared to control subjects. We therefore measured the angle of eye vergence in children previously diagnosed with ADHD while performing a cue task and compared the results to those from age-matched controls. We observed a strong modulation in the angle of vergence in the control group and a weak modulation in the ADHD group. In addition, in the control group the modulation in eye vergence was different between the informative cue and uninformative cue condition. This difference was less noticeable in the ADHD group. Our study supports the observation of deficient binocular vision in ADHD children. We argue that the observed disruption in vergence modulation in ADHD children is manifest of altered cognitive processing of sensory information. Our work may provide new insights into attention disorders, like ADHD. PMID:26694162

Observational Research Rigor Alone Does Not Justify Causal Inference

PubMed Central

Ejima, Keisuke; Li, Peng; Smith, Daniel L.; Nagy, Tim R.; Kadish, Inga; van Groen, Thomas; Dawson, John A.; Yang, Yongbin; Patki, Amit; Allison, David B.

2016-01-01

Background Differing opinions exist on whether associations obtained in observational studies can be reliable indicators of a causal effect if the observational study is sufficiently well controlled and executed. Materials and methods To test this, we conducted two animal observational studies that were rigorously controlled and executed beyond what is achieved in studies of humans. In study 1, we randomized 332 genetically identical C57BL/6J mice into three diet groups with differing food energy allotments and recorded individual self-selected daily energy intake and lifespan. In study 2, 60 male mice (CD1) were paired and divided into two groups for a 2-week feeding regimen. We evaluated the association between weight gain and food consumption. Within each pair, one animal was randomly assigned to an S group in which the animals had free access to food. The second paired animal (R group) was provided exactly the same diet that their S partner ate the day before. Results In study 1, across all three groups, we found a significant negative effect of energy intake on lifespan. However, we found a positive association between food intake and lifespan among the ad libitum feeding group: 29.99 (95% CI: 8.2 to 51.7) days per daily kcal. In study 2, we found a significant (P=0.003) group (randomized vs self-selected)-by-food consumption interaction effect on weight gain. Conclusions At least in nutrition research, associations derived from observational studies may not be reliable indicators of causal effects, even with the most rigorous study designs achievable. PMID:27711975

[Control of anticoagulation in patients with non-valvular atrial fibrillation in a primary care clinical practice setting in the different autonomous communities. PAULA study].

PubMed

Polo García, J; Barrios Alonso, V; Escobar Cervantes, C; Prieto Valiente, L; Lobos Bejarano, J M; Vargas Ortega, D; Prieto Díaz, M Á; Alonso Moreno, F J; Barquilla García, A

2017-04-01

To determine the differences between regions in the level of control of patients with non-valvular atrial fibrillation treated with vitamin K antagonists, included in the PAULA study. Observational, and coss-sectional/retrospective study, including 139 Primary Care physicians from 99 Health Care centres in all autonomous communities (except La Rioja). Anticoagulation control was defined as the time in therapeutic range assessed by either the direct method (poor control <60%), or the Rosendaal method (poor control <65%). A total of 1,524 patients were included. Small differences in baseline characteristics of the patients were observed. Differences in the percentage of time in therapeutic range were observed, according to the Rosendaal method (mean 69.0±17.7%), from 78.1%±16.6 (Basque Country) to 61.5±14% (Balearic Islands), by the direct method (mean 63.2±17.9%) from 73.6%±16.6 (Basque Country) to 57.5±15.7% (Extremadura). When comparing regions, in those where the Primary Care physicians assumed full control without restrictions on prescription, the percentage of time in therapeutic range by the direct method was 63.89 vs. 60.95% in those with restrictions (p=.006), by Rosendaal method, 69.39% compared with 67.68% (p=.1036). There are significant differences in the level of control between some regions are still inadequate. Regions in which the Primary Care physicians assumed the management of anticoagulation and without restrictions, time in therapeutic range was somewhat higher, and showed a favourable trend for better control. These findings may have clinical implications, and deserve consideration and specific analysis. Copyright © 2016 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España, S.L.U. All rights reserved.

Application of Absorbable Hemostatic Materials Observed in Thyroid Operation

NASA Astrophysics Data System (ADS)

Li, Yan-Ming; Liang, Zhen-Zhen; Song, Yan

2016-05-01

To observe the application effects of the absorbable hemostatic materials in thyroid operation. Methods: From May 2014 to January 2015, 100 patients with thyroid surgery in our university affiliated hospital were selected as the research object. Randomly divided into experimental group and control group, 50 cases in each group. Application of absorbable hemostatic hemostatic materials in the experimental group during the operation, the control group using the traditional mechanical methods of hemostasis hemostasis to observe the operation time, bleeding volume, postoperative drainage volume, complications and hospital stay of the two groups. Results: The operation time, bleeding volume, postoperative drainage and hospital stay in the experimental group were significantly lower in the study group than in the control group, and the difference between the two groups was statistically significant (P< 0.05); The satisfaction of patients in the experimental group was significantly higher than that in the control group, the difference was statistically significant in the two groups (P < 0.05); There was no significant difference in the incidence of wound bleeding complications between the study group and the control group (P > 0.05). Conclusion: Absorbable hemostatic materials can effectively shorten the operation time, reduce intraoperative blood loss and postoperative drainage, reduce the length of hospital stay and improve the success rate of surgery and patient satisfaction, which is worthy to be popularized in clinical thyroid surgery.

Outdoor-sleeping and other night-time activities in northern Ghana: implications for residual transmission and malaria prevention.

PubMed

Monroe, April; Asamoah, Obed; Lam, Yukyan; Koenker, Hannah; Psychas, Paul; Lynch, Matthew; Ricotta, Emily; Hornston, Sureyya; Berman, Amanda; Harvey, Steven A

2015-01-28

Despite targeted indoor residual spraying (IRS) over a six-year period and free mass distribution of long-lasting insecticide-treated nets (ITNs), malaria rates in northern Ghana remain high. Outdoor sleeping and other night-time social, cultural and economic activities that increase exposure to infective mosquito bites are possible contributors. This study was designed to document these phenomena through direct observation, and to explore the context in which they occur. During the late dry season months of February and March 2014, study team members carried out continuous household observations from dusk to dawn in one village in Ghana's Northern Region and one in Upper West Region. In-depth interviews with health workers and community residents helped supplement observational findings. Study team members completed observations of 182 individuals across 24 households, 12 households per site. Between the two sites, they interviewed 14 health workers, six community health volunteers and 28 community residents. In early evening, nearly all study participants were observed to be outdoors and active. From 18.00-23.00 hours, socializing, night school, household chores, and small-scale economic activities were common. All-night funerals, held outdoors and attended by large numbers of community members, were commonly reported and observed. Outdoor sleeping was frequently documented at both study sites, with 42% of the study population sleeping outdoors at some time during the night. While interviewees mentioned bed net use as important to malaria prevention, observed use was low for both indoor and outdoor sleeping. Net access within households was 65%, but only 17% of those with access used a net at any time during the night. Participants cited heat as the primary barrier and reported higher net use during the rainy season. Outdoor sleeping and other night-time activities were extensive, and could significantly increase malaria risk. These findings suggest that indoor-oriented control measures such as ITNs and IRS are insufficient to eliminate malaria in this setting, especially given the low net use observed. Development and evaluation of complementary outdoor control strategies should be prioritized. A research agenda is proposed to quantify the relative risk of outdoor night-time activities and test potential vector control interventions that might reduce that risk.

Guilt and Effortful Control: Two Mechanisms that Prevent Disruptive Developmental Trajectories

PubMed Central

Kochanska, Grazyna; Barry, Robin A.; Jimenez, Natasha B.; Hollatz, Amanda L.; Woodard, Jarilyn

2009-01-01

Children's guilt associated with transgressions and their capacity for effortful control are both powerful forces that inhibit disruptive conduct. We examined how guilt and effortful control, repeatedly observed from toddler to preschool age, jointly predict children's disruptive outcomes in two multi-method multi-trait longitudinal studies (N's 57 and 99). Disruptive outcomes were rated by mothers at 73 months (Study 1) and mothers, fathers, and teachers at 52 and 67 months (Study 2). In both studies, guilt moderated effects of effortful control: For highly guilt-prone children, variations in effortful control were unrelated to future disruptive outcomes, but for children who were less guilt prone, effortful control predicted such outcomes. Guilt may inhibit transgressions through an automatic response due to negative arousal triggered by memories of past wrongdoing, regardless of child capacity for deliberate inhibition. Effortful control that engages a deliberate restraint may offset risk for disruptive conduct conferred by low guilt. PMID:19634978

Management of infection control in dental practice.

PubMed

Smith, A; Creanor, S; Hurrell, D; Bagg, J; McCowan, M

2009-04-01

This was an observational study in which the management policies and procedures associated with infection control and instrument decontamination were examined in 179 dental surgeries by a team of trained surveyors. Information relating to the management of a wide range of infection control procedures, in particular the decontamination of dental instruments, was collected by interview and by examination of practice documentation. This study found that although the majority of surgeries (70%) claimed to have a management policy on infection control, only 50% of these were documented. For infection control policies, 79% of surgeries had access to the British Dental Association Advice Sheet A12. Infection control policies were claimed to be present in 89% of surgeries, of which 62% were documented. Seventy-seven per cent of staff claimed to have received specific infection control training, but for instrument decontamination this was provided mainly by demonstration (97%) or observed practice (88%). Many dental nurses (74%) and dental practitioners (57%) did not recognise the symbol used to designate a single-use device. Audit of infection control or decontamination activities was undertaken in 11% of surgeries. The majority of surgeries have policies and procedures for the management of infection control in dental practice, but in many instances these are not documented. The training of staff in infection control and its documentation is poorly managed and consideration should be given to development of quality management systems for use in dental practice.

Eating under observation: a systematic review and meta-analysis of the effect that heightened awareness of observation has on laboratory measured energy intake.

PubMed

Robinson, Eric; Hardman, Charlotte A; Halford, Jason C G; Jones, Andrew

2015-08-01

Laboratory paradigms are commonly used to study human energy intake. However, the extent to which participants believe their eating behavior is being measured may affect energy intake and is a methodologic factor that has received little consideration. Our main objective was to examine available evidence for the effect that heightened awareness of observation has on energy intake in a laboratory setting. We systematically reviewed laboratory studies that allowed for experimental examination of the effect that heightened awareness of observation has on energy intake. From these experimental studies we combined effect estimates using inverse variance meta-analysis, calculating the standardized mean difference (SMD) in energy intake between heightened-awareness and control conditions and qualitatively synthesized potential moderators of this effect. Nine studies, providing 22 comparisons, were eligible for inclusion. These studies largely sampled young women and examined the energy intake of energy-dense snack foods. Evidence indicated that heightened awareness of observation was associated with reduced energy intake when compared with the control condition (random-effects SMD: 0.45; 95% CI: 0.25, 0.66; P < 0.0001). We found little evidence that the type of experimental manipulation used to heighten awareness moderated the overall effect. The available evidence to date suggests that heightened awareness of observation reduces energy intake in a laboratory setting. These findings suggest that laboratory studies should attempt to minimize the degree to which participants are aware that their eating behavior is being measured. © 2015 American Society for Nutrition.

The role of vitamin D in the prevention of late-life depression.

PubMed

Okereke, Olivia I; Singh, Ankura

2016-07-01

In this article, we review current evidence regarding potential benefits of vitamin D for improving mood and reducing depression risk in older adults. We summarize gaps in knowledge and describe future efforts that may clarify the role of vitamin D in late-life depression prevention. MEDLINE and PsychINFO databases were searched for all articles on vitamin D and mood that had been published up to and including May 2015. Observational studies and randomized trials with 50 or more participants were included. We excluded studies that involved only younger adults and/or exclusively involved persons with current depression. Twenty observational (cross-sectional and prospective) studies and 10 randomized trials (nine were randomized placebo-controlled trials [RCTs]; one was a randomized blinded comparison trial) were reviewed. Inverse associations of vitamin D blood level or vitamin D intake with depression were found in 13 observational studies; three identified prospective relations. Results from all but one of the RCTs showed no statistically significant differences in depression outcomes between vitamin D and placebo groups. Observational studies were mostly cross-sectional and frequently lacked adequate control of confounding. RCTs often featured low treatment doses, suboptimal post-intervention changes in biochemical levels of vitamin D, and/or short trial durations. Vitamin D level-mood associations were observed in most, but not all, observational studies; results indicated that vitamin D deficiency may be a risk factor for late-life depression. However, additional data from well-designed RCTs are required to determine the impact of vitamin D in late-life depression prevention. Copyright © 2016 Elsevier B.V. All rights reserved.

AMPKα, hs-CRP and FcγR in diabetic nephropathy and drug intervention.

PubMed

Sun, Ping; Lu, Lei; Chen, Jun; Liu, Xiao Dan; Zhang, Qing; Wang, Xu

2018-06-01

The aim of this study was to investigate the roles of AMP-activated protein kinase α subunit (AMPKα), hypersensitive C-reactive protein (hs-CRP) and Fcγ receptor (FcγR) in diabetic nephropathy and drug intervention effects. Sixty Sprague Dawley male rats were randomly divided into the control (n=30) and observation (n=30) groups. The model of type 2 diabetic nephropathy was established by high-fat and high-glucose diet and streptozotocin injection. The rats in the observation group were treated with baicalein and the rats in control group did not receive any drug intervention. The pathological changes of kidneys were observed by hematoxylin and eosin (H&E) staining. The expression of AMPKα mRNA in renal tissue was detected by reverse transcription-polymerase chain reaction (RT-PCR). The levels of hs-CRP and FcγR were measured by enzyme-linked immunosorbent assay (ELISA) at 1, 4, 6 and 8 weeks after drug intervention and blood urea nitrogen (BUN) and the 24 h urinary micro-albumin (U-ALB) levels were compared at 1, 4, 6 and 8 weeks after intervention. After 8 weeks of drug intervention, the pathological changes of kidneys in the observation group were significantly lower than those in the control group (p<0.05), while the relative expression levels of AMPKα mRNA and protein in the control group were higher than those in the observation group (p<0.05). The levels of hs-CRP, BUN and 24 h U-ALB in the control group were significantly higher than those in the observation group at different time-points after drug intervention and the level of FcγR in the control group was significantly lower than that in the observation group (p<0.05). Baicalein may protect renal function by inhibiting the expression of AMPKα and inflammatory reaction, and can also decrease BUN and 24 h U-ALB levels and improve the pathological changes of the kidney.

Investigating methotrexate toxicity within a randomized double-blinded, placebo-controlled trial: rationale and design of the Cardiovascular Inflammation Reduction Trial-Adverse Events (CIRT-AE) Study

USDA-ARS?s Scientific Manuscript database

Background: The role of low dose methotrexate (LDM) in potential serious toxicities remains unclear despite its common use. Prior observational studies investigating LDM toxicity compared LDM to other active drugs. Prior placebo-controlled clinical trials of LDM in inflammatory conditions were not l...

MR Spectroscopy to Distinguish between Supratentorial Intraventricular Subependymoma and Central Neurocytoma.

PubMed

Ueda, Fumiaki; Aburano, Hiroyuki; Ryu, Yasuji; Yoshie, Yuichi; Nakada, Mitsutoshi; Hayashi, Yutaka; Matsui, Osamu; Gabata, Toshifumi

2017-07-10

The purpose of this study was to discriminate supratentorial intraventricular subependymoma (SIS) from central neurocytoma (CNC) using magnetic resonance spectroscopy (MRS). Single-voxel proton MRS using a 1.5T or 3T MR scanner from five SISs, five CNCs, and normal controls were evaluated. They were examined using a point-resolved spectroscopy. Automatically calculated ratios comparing choline (Cho), N-acetylaspartate (NAA), myoinositol (MI), and/or glycine (Gly) to creatine (Cr) were determined. Evaluation of Cr to unsuppressed water (USW) was also performed. Mann-Whitney U test was carried out to test the significance of differences in the metabolite ratios. Detectability of lactate (Lac) and alanine (Ala) was evaluated. Although a statistically significant difference (P < 0.0001) was observed in Cho/Cr among SIS, control spectra, and CNC, no statistical difference was noted between SIS and control spectra (P = 0.11). Statistically significant differences were observed in NAA/Cr between SIS and CNC (P = 0.04) or control spectra (P < 0.0001). A statistically significant difference was observed in MI and/or Gly to Cr between SIS and control spectra (P = 0.03), and CNC and control spectra (P < 0.0006). There were no statistical differences between SIS and CNC for MI and/or Gly to Cr (P = 0.32). Significant statistical differences were found between SIS and control spectra (P < 0.0053), control spectra and CNC (P < 0.0016), and SIS and CNC (P < 0.0083) for Cr to USW. Lac inverted doublets were confirmed in two SISs. Triplets of Lac and Ala were detected in four spectra of CNC. The present study showed that MRS can be useful in discriminating SIS from CNC.

Plasma lipids, lipoproteins, and triglyceride turnover in eu- and hypo-thyroid rats and rats on a hypocaloric diet.

PubMed

Dory, L; Krause, B R; Roheim, P S

1981-08-01

Lipid and lipoprotein concentration, and triglyceride turnover were studied in control, thyroidectomized, and pair-fed control rats (pair-fed to match the food intake of the thyroidectomized rats). Thyroidectomy induced a significant increase in plasma cholesterol (and low density lipoprotein) concentrations and a decrease in plasma triglyceride (and very low density lipoprotein) concentrations. Changes in similar direction but of smaller magnitude were observed in the plasma of the pair-fed control rats. To further investigate triglyceride metabolism in these three groups of animals, triglyceride turnover was studied in fasted, unrestrained, and unanesthetized rats, following injection of [2-3H]glycerol. Peak incorporation of [2-3H]glycerol into plasma triglyceride occurred in all three groups of animals at 25 min after precursor administration, although the maximal incorporation was substantially lower in the thyroidectomized group than in either of the control groups. Thereafter, plasma triglyceride radioactivity decayed monoexponentially with a half-life of 24 +/- 1 min for both normal and pair-fed control rats, compared with the half-life of 41 +/- 3 min observed in the thyroidectomized rats. The calculated apparent fractional catabolic rates were thus 0.029 min-1 for both control groups and only 0.017 min-1 for the thyroidectomized animals. The apparent total catabolic rates of plasma triglyceride were 299 +/- 11, 138 +/- 11, and 48 +/- 4 micrograms triglyceride . min-1 for the normal controls, pair-fed controls, and thyroidectomized rats, respectively. These data further emphasize the importance of thyroid hormones in regulating plasma lipid and lipoprotein metabolism and, specifically, indicate that hypothyroidism results in a reduction of triglyceride secretion into, and the removal from, circulation. Furthermore, evidence was presented that the decreased caloric intake of the hypothyroid animals cannot, in itself, account for this observation.

The Science ELF: Assessing the enquiry levels framework as a heuristic for professional development

NASA Astrophysics Data System (ADS)

Wheeler, Lindsay B.; Bell, Randy L.; Whitworth, Brooke A.; Maeng, Jennifer L.

2015-01-01

This study utilized an explanatory sequential mixed methods approach to explore randomly assigned treatment and control participants' frequency of inquiry instruction in secondary science classrooms. Eleven treatment participants received professional development (PD) that emphasized a structured approach to inquiry instruction, while 10 control participants received no PD. Two representative treatment participants were interviewed and observed to provide an in-depth understanding of inquiry instruction and factors affecting implementation. Paired t-tests were used to analyze quantitative data from observation forms, and a constant comparative approach was used to analyze qualitative data from surveys, interviews, purposeful observations and artifacts. Results indicated that treatment participants implemented inquiry significantly more frequently than control participants (p < .01). Two treatment participants' instruction revealed that both used a similar structure of inquiry but employed different types of interactions and emphasized different scientific practices. These differences may be explained by the participants' understandings of and beliefs about inquiry and structuring inquiry. The present study has the potential to inform how methods of structuring inquiry instruction and teaching scientific practices are addressed in teacher preparation.

Handedness, functional cerebral hemispheric lateralization, and cognition in male-to-female transsexuals receiving cross-sex hormone treatment.

PubMed

Wisniewski, Amy B; Prendeville, Mary T; Dobs, Adrian S

2005-04-01

This study examined the impact of sex hormones on functional cerebral hemispheric lateralization and cognition in a group of male-to-female transsexuals receiving cross-sex hormone therapy compared to eugonadal men with a male gender identity. Cerebral lateralization was measured with a handedness questionnaire and a visual-split-field paradigm and cognitive tests sensitive to sex hormone exposure (identical pictures, 3-D mental rotation, building memory) were also administered. Endocrine measures on the day of participation for transsexual and control subjects included total testosterone, free testosterone, estradiol, gonadotropins, and sex hormone binding globulin concentrations. Compared to controls, male-to-female transsexuals had elevated estradiol and sex hormone binding globulin concentrations and suppressed testosterone concentrations. Transsexual subjects showed a trend toward less exclusive right-handedness than controls. No group differences were observed on the visual-split-field or cognitive tasks. No direct associations were observed between endocrine measures and the laterality measures and cognitive performance. Previous observations of female-typical patterns in cerebral lateralization and cognitive performance in male-to-female transsexuals were not found in the current study.

Vesicle Adhesion and Fusion Studied by Small-Angle X-Ray Scattering.

PubMed

Komorowski, Karlo; Salditt, Annalena; Xu, Yihui; Yavuz, Halenur; Brennich, Martha; Jahn, Reinhard; Salditt, Tim

2018-04-24

We have studied the adhesion state (also denoted by docking state) of lipid vesicles as induced by the divalent ions Ca 2+ or Mg 2+ at well-controlled ion concentration, lipid composition, and charge density. The bilayer structure and the interbilayer distance in the docking state were analyzed by small-angle x-ray scattering. A strong adhesion state was observed for DOPC:DOPS vesicles, indicating like-charge attraction resulting from ion correlations. The observed interbilayer separations of ∼1.6 nm agree quantitatively with the predictions of electrostatics in the strong coupling regime. Although this phenomenon was observed when mixing anionic and zwitterionic (or neutral) lipids, pure anionic membranes (DOPS) with highest charge density σ resulted in a direct phase transition to a multilamellar state, which must be accompanied by rupture and fusion of vesicles. To extend the structural assay toward protein-controlled docking and fusion, we have characterized reconstituted N-ethylmaleimide-sensitive factor attachment protein receptors in controlled proteoliposome suspensions by small-angle x-ray scattering. Copyright © 2018 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Active-comparator design and new-user design in observational studies

PubMed Central

Yoshida, Kazuki; Solomon, Daniel H.; Kim, Seoyoung C.

2015-01-01

SUMMARY Over the past decade, an increasing number of observational studies have examined the effectiveness or safety of rheumatoid arthritis treatments. However, unlike randomized controlled trials (RCTs), observational studies of drug effects face methodological challenges including confounding by indication. Two design principles - active comparator design and new user design can help mitigate such challenges in observational studies. To improve validity of study findings, observational studies should be designed in such a way that makes them more closely approximate RCTs. The active comparator design compares the drug of interest to another commonly used agent for the same indication, rather than a ‘non-user’ group. This principle helps select treatment groups similar in treatment indications (both measured and unmeasured characteristics). The new user design includes a cohort of patients from the time of treatment initiation, so that it can assess patients’ pretreatment characteristics and capture all events occurring anytime during follow-up. PMID:25800216

Risk of bias and confounding of observational studies of Zika virus infection: A scoping review of research protocols

PubMed Central

Haby, Michelle M.; Martínez-Vega, Ruth; Pinzón-Flores, Carlos E.; Smith, Emma; Pinart, Mariona; Broutet, Nathalie; Becerra-Posada, Francisco; Aldighieri, Sylvain; Van Kerkhove, Maria D.

2017-01-01

Introduction Given the severity and impact of the current Zika virus (ZIKV) outbreak in the Americas, numerous countries have rushed to develop research studies to assess ZIKV and its potential health consequences. In an effort to ensure that studies are comprehensive, both internally and externally valid, and with reliable results, the World Health Organization, the Pan American Health Organization, Institut Pasteur, the networks of Fiocruz, the Consortia for the Standardization of Influenza Seroepidemiology (CONSISE) and the International Severe Acute Respiratory and Emerging Infection Consortium (ISARIC) have generated six standardized clinical and epidemiological research protocols and questionnaires to address key public health questions on ZIKV. Methods We conducted a systematic search of ongoing study protocols related to ZIKV research. We analyzed the content of protocols of 32 cohort studies and 13 case control studies for systematic bias that could produce erroneous results. Additionally we aimed to characterize the risks of bias and confounding in observational studies related to ZIKV and to propose ways to minimize them, including the use of six newly standardized research protocols. Results Observational studies of ZIKV face an array of challenges, including measurement of exposure and outcomes (microcephaly and Guillain-Barré Syndrome). Potential confounders need to be measured where known and controlled for in the analysis. Selection bias due to non-random selection is a significant issue, particularly in the case-control design, and losses to follow-up is equally important for the cohort design. Conclusion Observational research seeking to answer key questions on the ZIKV should consider these restrictions and take precautions to minimize bias in an effort to provide reliable and valid results. Utilization of the standardized research protocols developed by the WHO, PAHO, Institut Pasteur, and CONSISE will harmonize the key methodological aspects of each study design to minimize bias at different stages of the study. Biases need to be considered by researchers implementing the standardized protocols as well as by users of observational epidemiological studies of ZIKV. PMID:28686621

Untapped Potential of Observational Research to Inform Clinical Decision Making: American Society of Clinical Oncology Research Statement.

PubMed

Visvanathan, Kala; Levit, Laura A; Raghavan, Derek; Hudis, Clifford A; Wong, Sandra; Dueck, Amylou; Lyman, Gary H

2017-06-01

ASCO believes that high-quality observational studies can advance evidence-based practice for cancer care and are complementary to randomized controlled trials (RCTs). Observational studies can generate hypotheses by evaluating novel exposures or biomarkers and by revealing patterns of care and relationships that might not otherwise be discovered. Researchers can then test these hypotheses in RCTs. Observational studies can also answer or inform questions that either have not been or cannot be answered by RCTs. In addition, observational studies can be used for postmarketing surveillance of new cancer treatments, particularly in vulnerable populations. The incorporation of observational research as part of clinical decision making is consistent with the position of many leading institutions. ASCO identified five overarching recommendations to enhance the role of observational research in clinical decision making: (1) improve the quality of electronic health data available for research, (2) improve interoperability and the exchange of electronic health information, (3) ensure the use of rigorous observational research methodologies, (4) promote transparent reporting of observational research studies, and (5) protect patient privacy.

Prevention of Alzheimer disease

PubMed Central

Scalco, Monica Zavaloni; van Reekum, Robert

2006-01-01

OBJECTIVE To review the evidence regarding prevention of Alzheimer disease (AD) in order to highlight the role of family medicine. QUALITY OF EVIDENCE Most of the evidence relating to prevention of AD is derived from observational (cross-sectional, case-control, or longitudinal) studies. Evidence from randomized controlled trials (RCTs) is available only for blood pressure control and for hormone replacement therapy for menopausal women. MAIN MESSAGE Many preventive approaches to AD have been identified, but no RCTs support their efficacy. Evidence from RCTs supports the effectiveness of blood pressure control in reducing incidence of AD, but demonstrates that postmenopausal women’s use of estrogen is ineffective in reducing it. Observational studies suggest that some preventive approaches, such as healthy lifestyle, ongoing education, regular physical activity, and cholesterol control, play a role in prevention of AD. These approaches can and should be used for every patient because they carry no significant risk. Currently, no effective pharmacologic interventions have been researched enough to support their use in prevention of AD. CONCLUSION Health professionals should educate patients, especially patients at higher risk of AD, about preventive strategies and potentially modifiable risk factors. PMID:16529393

Treatment of adenoviral keratoconjunctivitis with a combination of povidone-iodine 1.0% and dexamethasone 0.1% drops: a clinical prospective controlled randomized study.

PubMed

Kovalyuk, Natalya; Kaiserman, Igor; Mimouni, Michael; Cohen, Ornit; Levartovsky, Shmuel; Sherbany, Hilda; Mandelboim, Michal

2017-12-01

To determine the efficacy of combination povidone-iodine (PVP-I) 1.0% eyedrops and dexamethasone 0.1% eyedrops in the treatment of adenoviral keratoconjunctivitis. In a prospective, randomized, controlled, double-blinded clinical trial patients with recent adenoviral keratoconjunctivitis (diagnosed clinically and confirmed by PCR), we randomly divided into three treatment groups: study group - received PVP-I 1.0% and dexamethasone 0.1%, control 1 group - received dexamethasone 0.1% and control 2 group - received lubricating eyedrops (hypromellose 0.3%). The treatment was administered four times a day in each group. All patients were examined and filled a questionnaire before treatment and on the 3rd, 5th and 7th days of treatment. We included in the study 78 eyes (26 in each group). Adenovirus type 8 was the most common pathogen (83% of cases). The fastest improvement in patients red eyes, discharge, superficial punctate keratitis and pseudomembranes was observed in the study group (p < 0.001). Those patients reached a near complete recovery in 5-7 days, which was also confirmed by reduction in Adenovirus titres by PCR. The slowest improvement was in the control 2 group. Subepithelial infiltrates (SEI) were observed in 44% of the control 1 group, 20% of the control 2 group and in 0% of the study group. The rate of reduction in Adenovirus titres was the slowest in the control 1 group. The combination of PVP-I 1.0% and dexamethasone 0.1% four times a day can reduce symptoms and expedite recovery in epidemic keratoconjunctivitis patients. © 2017 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

The effect of observing novice and expert performance on acquisition of surgical skills on a robotic platform

PubMed Central

Harris, David J.; Vine, Samuel J.; Wilson, Mark R.; McGrath, John S.; LeBel, Marie-Eve

2017-01-01

Background Observational learning plays an important role in surgical skills training, following the traditional model of learning from expertise. Recent findings have, however, highlighted the benefit of observing not only expert performance but also error-strewn performance. The aim of this study was to determine which model (novice vs. expert) would lead to the greatest benefits when learning robotically assisted surgical skills. Methods 120 medical students with no prior experience of robotically-assisted surgery completed a ring-carrying training task on three occasions; baseline, post-intervention and at one-week follow-up. The observation intervention consisted of a video model performing the ring-carrying task, with participants randomly assigned to view an expert model, a novice model, a mixed expert/novice model or no observation (control group). Participants were assessed for task performance and surgical instrument control. Results There were significant group differences post-intervention, with expert and novice observation groups outperforming the control group, but there were no clear group differences at a retention test one week later. There was no difference in performance between the expert-observing and error-observing groups. Conclusions Similar benefits were found when observing the traditional expert model or the error-strewn model, suggesting that viewing poor performance may be as beneficial as viewing expertise in the early acquisition of robotic surgical skills. Further work is required to understand, then inform, the optimal curriculum design when utilising observational learning in surgical training. PMID:29141046

Increased myosin heavy chain-beta with atrial expression of ventricular light chain-2 in canine cardiomyopathy.

PubMed

Fuller, Geraldine A; Bicer, Sabahattin; Hamlin, Robert L; Yamaguchi, Mamoru; Reiser, Peter J

2007-10-01

Dilated cardiomyopathy is a naturally occurring disease in humans and dogs. Human studies have shown increased levels of myosin heavy chain (MHC)-beta in failing ventricles and the left atria (LA) and of ventricular light chain (VLC)-2 in the right atria in dilated cardiomyopathy. This study evaluates the levels of MHC-beta in all heart chambers in prolonged canine right ventricular pacing. In addition, we determined whether levels of VLC2 were altered in these hearts. Failing hearts demonstrated significantly increased levels of MHC-beta in the right atria, right atrial appendage, LA, left atrial appendage (LAA), and right ventricle compared with controls. Significant levels of VLC2 were detected in the right atria of paced hearts. Differences in MHC-beta expression were observed between the LA and the LAA of paced and control dogs. MHC-beta expression was significantly greater in the LA of paced and control dogs compared with their respective LAA. The cardiac myosin isoform shifts in this study were similar to those observed in end-stage human heart failure and more severe than those reported in less prolonged pacing models, supporting the use of this model for further study of end-stage human heart failure. The observation of consistent differences between sampling sites, especially LA versus LAA, indicates the need for rigorous sampling consistency in future studies.

Occupational solvent exposure and adult chronic lymphocytic leukemia: No risk in a population-based case-control study in four Nordic countries.

PubMed

Talibov, Madar; Auvinen, Anssi; Weiderpass, Elisabete; Hansen, Johnni; Martinsen, Jan-Ivar; Kjaerheim, Kristina; Tryggvadottir, Laufey; Pukkala, Eero

2017-09-15

The aim of this study was to assess the effect of occupational solvent exposure on the risk of adult chronic lymphocytic leukemia (CLL). The current case-control study was nested in the Nordic Occupational Cancer Study (NOCCA) cohort. 20,615 CLL cases diagnosed in 1961-2005 in Finland, Iceland, Norway, and Sweden, and 103,075 population-based controls matched by year of birth, sex, and country were included. Occupational histories for cases and controls were obtained from census records in 1960, 1970, 1980/1981, and 1990. Exposure to selected solvents was estimated by using the NOCCA job-exposure matrix (NOCCA-JEM). Odds ratios (OR) and 95% confidence intervals (95% CI) were estimated by using conditional logistic regression models. Overall, nonsignificant CLL risk elevations were observed for methylene chloride, perchloroethylene, and 1,1,1-trichloroethane. Compared to unexposed, significantly increased risks were observed for cumulative perchloroethylene exposure ≤13.3 ppm-years (OR = 1.85, 95% CI 1.16-2.96) and average life-time perchloroethylene exposure ≤2.5 ppm (1.61, 95% CI 1.01-2.56) among women, and cumulative methylene chloride exposure ≤12.5 ppm-years (OR = 1.19, 95% CI 1.01-1.41) and 12.5-74.8 ppm-years (OR = 1.23, 95% CI 1.01-1.51) among men in an analysis with 5 years lag-time, though without dose-response pattern. Decreased CLL risk was observed for aliphatic and alicyclic hydrocarbon solvents and toluene. This study did not support associations for solvent exposure and CLL. Observed weak associations for methylene chloride, perchloroethylene, 1,1,1-trichloroethane exposures, aliphatic and alicyclic hydrocarbons and toluene were not consistent across sexes, and showed no gradient with amount of exposure. © 2017 UICC.

Using full-cohort data in nested case-control and case-cohort studies by multiple imputation.

PubMed

Keogh, Ruth H; White, Ian R

2013-10-15

In many large prospective cohorts, expensive exposure measurements cannot be obtained for all individuals. Exposure-disease association studies are therefore often based on nested case-control or case-cohort studies in which complete information is obtained only for sampled individuals. However, in the full cohort, there may be a large amount of information on cheaply available covariates and possibly a surrogate of the main exposure(s), which typically goes unused. We view the nested case-control or case-cohort study plus the remainder of the cohort as a full-cohort study with missing data. Hence, we propose using multiple imputation (MI) to utilise information in the full cohort when data from the sub-studies are analysed. We use the fully observed data to fit the imputation models. We consider using approximate imputation models and also using rejection sampling to draw imputed values from the true distribution of the missing values given the observed data. Simulation studies show that using MI to utilise full-cohort information in the analysis of nested case-control and case-cohort studies can result in important gains in efficiency, particularly when a surrogate of the main exposure is available in the full cohort. In simulations, this method outperforms counter-matching in nested case-control studies and a weighted analysis for case-cohort studies, both of which use some full-cohort information. Approximate imputation models perform well except when there are interactions or non-linear terms in the outcome model, where imputation using rejection sampling works well. Copyright © 2013 John Wiley & Sons, Ltd.

The effects of an office ergonomics training and chair intervention on worker knowledge, behavior and musculoskeletal risk.

PubMed

Robertson, Michelle; Amick, Benjamin C; DeRango, Kelly; Rooney, Ted; Bazzani, Lianna; Harrist, Ron; Moore, Anne

2009-01-01

A large-scale field intervention study was undertaken to examine the effects of office ergonomics training coupled with a highly adjustable chair on office workers' knowledge and musculoskeletal risks. Office workers were assigned to one of three study groups: a group receiving the training and adjustable chair (n=96), a training-only group (n=63), and a control group (n=57). The office ergonomics training program was created using an instructional systems design model. A pre/post-training knowledge test was administered to all those who attended the training. Body postures and workstation set-ups were observed before and after the intervention. Perceived control over the physical work environment was higher for both intervention groups as compared to workers in the control group. A significant increase in overall ergonomic knowledge was observed for the intervention groups. Both intervention groups exhibited higher level behavioral translation and had lower musculoskeletal risk than the control group.

Modelling and Control of Robotic Leg as Assistive Device

NASA Astrophysics Data System (ADS)

Jingye, Yee; Zain, Badrul Aisham bin Md

2017-10-01

The ageing population (people older than 60 years old) is expected to constitute 21.8% of global population by year 2050. When human ages, bodily function including locomotors will deteriorate. Besides, there are hundreds of thousands of victims who suffer from multiple health conditions worldwide that leads to gait impairment. A promising solution will be the lower limb powered-exoskeleton. This study is to be a start-up platform to design a lower limb powered-exoskeleton for a normal Malaysian male, by designing and simulating the dynamic model of a 2-link robotic leg to observe its behaviour under different input conditions with and without a PID controller. Simulink in MATLAB software is used as the dynamic modelling and simulation software for this study. It is observed that the 2-links robotic leg behaved differently under different input conditions, and perform the best when it is constrained and controlled by PID controller. Simulink model is formed as a foundation for the upcoming researches and can be modified and utilised by the future researchers.

Effects of combining CBCT technology with visual root canal recurrence in treatment of elderly patients with dental pulp disease.

PubMed

Cui, J-J; Peng, B; Lin, W

2017-03-01

The aim of this study is to analyze the effects of combining cone beam computed tomography (CBCT) technology with visual root canal recurrence in the treatment of elderly patients with dental pulp disease. 56 cases of elderly patients with dental pulp disease were contiguously selected, and randomly divided into the control group (70 teeth from 27 patients) and the observation group (77 teeth from the rest 29 patients). We adopted CBCT technology combined with conventional root canal therapy in control group and CBCT technology combined with visual root canal recurrence in observation group to compare the clinical effects. It was found that there was no statistical difference in duration of operation between the two groups (p>0.05). The operation times and the VAS during and after operation of the observation group were significantly less than that of the control group (p<0.05). The duration of follow-up of the two groups was both about 18 months. Successful rates of treatment for 6 months and by the end of follow-up visit in the observation group were both significantly higher than those in the control group (p<0.05). The correct filling rate, good filling rate and fair filling rate in the observation group were significantly higher than those of the control group (p<0.05). CBCT technology combined with visual root canal recurrence can significantly improve the near and long-term treatment effects of elderly patients with dental pulp disease.

A Common Profile of Disordered Angiogenic Factor Production and the Exacerbation of Inflammation in Early Preeclampsia, Late Preeclampsia, and Intrauterine Growth Restriction.

PubMed

Kwiatkowski, Sebastian; Dołęgowska, Barbara; Kwiatkowska, Ewa; Rzepka, Rafał; Torbè, Andrzej; Bednarek-Jędrzejek, Magdalena

2016-01-01

Preeclampsia and intrauterine growth restriction are two separate disease entities that, according to numerous reports, share the same pathogenesis. In both, angiogenesis disorders and generalized inflammation are the dominant symptoms. In this study, we hypothesized that both diseases demonstrate the same profile in early preeclampsia, late preeclampsia, and intrauterine growth restriction patients, with the only difference being the degree of exacerbation of lesions. One hundred sixty-seven patients were enrolled in the study and divided into four groups: early preeclampsia, late preeclampsia, and intrauterine growth restriction groups, and one control group. Concentrations of the angiogenesis and inflammatory markers soluble fms-like tyrosine kinase receptor 1, placental growth factor, high-sensitivity C-reactive protein, and interleukin-6 were determined, and the behavior of these markers and correlations among them were studied. Higher concentrations of soluble fms-like tyrosine kinase receptor 1, high-sensitivity C-reactive protein, and interleukin-6 and a lower concentration of placental growth factor were observed in the study groups compared with the control group. No differences in concentrations of the studied markers were found among the study groups but significant correlations were observed. The higher values for the angiogenesis and inflammatory markers both in preeclampsia patients and patients with intrauterine growth restriction of placental origin compared with the control group suggest the existence of the same underlying disorders in the development of these pathologies. The observed mutual correlations for disordered angiogenesis and inflammatory markers are suggestive of a mutual relationship between these processes in the development of pathologies evolving secondary to placental ischemia. The same lesion profile was observed for both preeclampsia and 'placental' intrauterine growth restriction patients, which could be used in developing common diagnostic criteria for pregnant patients.

Systematic Review of Clinical Outcomes Following Various Treatment Options for Patients with Extraabdominal Desmoid Tumors.

PubMed

Smith, Kortnye; Desai, Jayesh; Lazarakis, Smaro; Gyorki, David

2018-06-01

Desmoid tumors (DT) are rare clonal proliferations that arise from mesenchymal cells. These tumors do not metastasize but are locally aggressive, and their growth may lead to significant morbidity. Their clinical course is both variable and unpredictable; tumors may rapidly progress but in other instances remain stable or regress without intervention. To examine current treatment of DT and assist with decision-making at time of presentation. A literature search was conducted of MEDLINE and Cochrane databases for published studies (1995-July 2015) using the search terms fibromatosis aggressive, desmoid with drug therapy, radiation therapy, prevention and control, radiotherapy, surgery, and therapy. Articles were categorized as surgery, radiation, surgery + radiation, systemic therapy, and front-line observation. Articles were included if they reported a retrospective or prospective comparative or observational study with an analyzed sample size of 10 patients or more with confirmed diagnosis of desmoid tumor and described one of the following clinical outcomes: relapse- or progression-free survival, local control rate, response rate. 258 articles were reviewed; following screening for eligibility, 54 were identified; following full-text screen, 31 were included in final evaluation. The control rate for patients treated with a "wait and see" observational approach compared favorably with management with surgery and resulted in disease control rates of between 60 and 92%. Decision-making in this rare tumor is complicated by the range of treatment options available. Our evidence supports use of an upfront observational approach.

Extended findings of Brain Metabolite Normalization in MA-Dependent Subjects Across Sustained Abstinence: A Proton MRS Study

PubMed Central

Salo, Ruth; Buonocore, Michael H.; Leamon, Martin; Natsuaki, Yutaka; Waters, Christy; Moore, Charles D.; Galloway, Gantt P.; Nordahl, Thomas E.

2010-01-01

Objective The goal of the present study was to extend our previous findings on long-term methamphetamine (MA) use and drug abstinence on brain metabolite levels in an expanded group of MA-dependent individuals. Methods Seventeen MA abusers with sustained drug abstinence (1 year to 5 years), 30 MA abusers with short-term drug abstinence (1 month to 6 months) and 24 non-substance using controls were studied using MR spectroscopy (MRS). MRS measures of NAA/Cr, Cho/Cr and Cho/NAA were obtained in the anterior cingulate cortex (ACC) and in the primary visual cortex (PVC). Results ACC-Cho/NAA values were abnormally high in the short-term abstinent group compared to controls [F(1,52)=18.76, p<0.0001]. No differences were observed between controls and the long-term abstinent group [F(1,39)=0.97, p=0.97]. New evidence of lower ACC-NAA/Cr levels were observed in the short-term abstinent MA abusers compared to controls [F(1,52)=23.05, p<0.0001] and long-term abstinent MA abusers [F(1,45)=7.06, p=0.01]. No differences were observed between long-term abstinent MA abusers and controls [F(1,39)=0.48, p=0.49]. Conclusions The new findings of relative NAA/Cr normalization across periods of abstinence suggest that adaptive changes following cessation of MA abuse may be broader than initially thought. These changes may contribute to some degree of normalization of neuronal function in the ACC. PMID:20739127

Balneotherapy in fibromyalgia: a single blind randomized controlled clinical study.

PubMed

Ozkurt, Seçil; Dönmez, Arif; Zeki Karagülle, M; Uzunoğlu, Emel; Turan, Mustafa; Erdoğan, Nergis

2012-07-01

We aimed to evaluate the effectiveness of balneotherapy in fibromyalgia management. Fifty women with fibromyalgia under pharmacological treatment were randomly assigned to either the balneotherapy (25) or the control (25) group. Four patients from the balneotherapy group and one patient from the control group left the study after randomization. The patients in the balneotherapy group (21) had 2 thermomineral water baths daily for 2 weeks in Tuzla Spa Center. The patients in the control group (24) continued to have their medical treatment and routine daily life. An investigator who was blinded to the study arms assessed the patients. All patients were assessed four times; at the beginning of the study, at the end of the 2nd week, the 1st month, and the 3rd month after balneotherapy. Outcome measures of the study were pain intensity, Fibromyalgia Impact Questionnaire (FIQ), Beck Depression Inventory (BDI), patient's global assessment, investigator's global assessment, SF-36 scores, and tender point count. Balneotherapy was found to be superior at the end of the cure period in terms of pain intensity, FIQ, Beck Depression Inventory, patient's global assessment, investigator's global assessment scores, and tender point count as compared to the control group. The superiority of balneotherapy lasted up to the end of the 3rd month, except for the Beck Depression Inventory score and the investigator's global assessment score. Significant improvements were observed in PF, GH, and MH subscales of SF-36 during the study period in the balneotherapy group; however, no such improvement was observed in the control group. Balneotherapy was superior only in VT subscale at the end of therapy and at the end of the third month after the therapy as compared to the controls. It was concluded that balneotherapy provides beneficial effects in patients with fibromyalgia.

The biological control of Pomacea canaliculata population by rice-duck mutualism in paddy fields

Treesearch

Kiang Liang; Jia-en Zhang; Li Fang; Benliang Zaho; Mingzhu Luo; Prem Parajuli; Ying Ouyang

2013-01-01

Duck has been used as a non-chemical control method against Pomacea canaliculata Lamarck, but little is known about its principles that underlie the control of snail populations. An indoor experiment was initially used to observe the predation potential of ducks, followed by replicated field trials. In the indoor studies, ducks effectively preyed on...

[False positive result in mammography and its association with the presence of obesity: a case-control study].

PubMed

Castro-Ibarra, Marisela; Menchaca-Díaz, Rufino; Cabrales-Ruvalcaba, J Jesús; Luna-V Gómez, Rosa Alicia

2016-01-01

To analyze the association between a false positive result in mammography and obesity, inside the breast cancer early detection program in women affiliated to the Institute of Security and Social Services for Government and Municipality workers of the State of Baja California (ISSSTECALI). A case-control, retrospective study was done in women affiliated to ISSSTECALI to whom a mammography was performed between 2009 and 2012. Women with a false positive result in mammography were included as cases. Controls were women with a true negative result in mammography. Three controls were randomly selected for each case. Obesity was established with the body mass index (BMI) consigned in the woman's clinical file. Age and estrogen replacement therapy were included as co-variables. Seventy nine cases were identified and 237 controls were included. Obesity was observed in 54.4% of cases and in 41.3% of controls (odds ratio: 1.69; 95% confidence interval for odds ratio: 1.01-2.82; p value: 0.043). A logistic regression model including covariables maintained the observed association (p = 0.044). No association was found with analyzed co-variables. A false positive result in mammography was associated with the presence of obesity.

The Evidence for the Role of Nutraceuticals in the Management of Pediatric Migraine: a Review.

PubMed

Orr, Serena L

2018-04-04

Nutraceuticals are a form of complementary and alternative medicine that is commonly used by children and adolescents with migraine. In this review, observational studies, randomized controlled trials, systematic reviews, and meta-analyses on the efficacy and safety of single compound nutraceuticals for the management of migraine in children and adolescents were identified through a literature search of MEDLINE, Embase, and EBM Reviews-Cochrane Central Register of Controlled Trials. Twenty-one studies were reviewed, of which 11 were observational studies, 7 were randomized controlled trials, and 3 were systematic reviews. Six different nutraceuticals were included in the review: vitamin D, riboflavin, coenzyme Q10, magnesium, butterbur, and polyunsaturated fatty acids. All but three of the studies assessed the role of nutraceuticals in migraine prevention, while three studies evaluated the role of intravenous magnesium for acute migraine management. Overall, the quality and size of the studies were limited. Due to low quality evidence and limited studies, no definite conclusions can be drawn on the efficacy of nutraceuticals for the treatment of pediatric migraine. Future studies are warranted in order to establish evidence upon which to define the role of nutraceuticals in this patient population.

Simvastatin as an Adjunct to Conventional Therapy of Non-infectious Uveitis: A Randomized, Open-Label Pilot Study.

PubMed

Shirinsky, Ivan V; Biryukova, Anastasia A; Shirinsky, Valery S

2017-12-01

Statins have been shown to reduce ocular inflammation in animal models of uveitis and to prevent development of uveitis in observational studies. There have been no experimental human studies evaluating statins' efficacy and safety in uveitis. In this study, we aimed to investigate efficacy and safety of simvastatin in patients with uveitis. For this single-center, open-label, randomized study, we enrolled patients with acute non-infectious uveitis. The patients were randomized to receive 40 mg simvastatin per day for 2 months in addition to conventional treatment or conventional treatment alone. The studied outcomes were the rate of steroid-sparing control of ocular inflammation, measures of ocular inflammation, intraocular pressure, and visual acuity. Fifty patients were enrolled in the study. Twenty-five patients were randomly assigned to receive simvastatin with conventional treatment and 25 to conventional treatment alone. Simvastatin was associated with significantly higher rates of steroid-sparing ocular inflammation control, decrease in anterior chamber inflammation, and improvement in visual acuity. The treatment was well tolerated, no serious adverse effects were observed. Our findings suggest that statins may have therapeutic potential in uveitis. These results need to be confirmed in double-blind, randomized, controlled studies.

Research on the relativity between gene polymorphism and children cardiac insufficiency.

PubMed

He, X-H; Li, C-L; Ling, N; Wang, Q-W; Wang, Z-Z; An, X-J

2017-08-01

We analyzed the relationship between Mink-S27 gene polymorphism and children with cardiac insufficiency. From April 2013 to April 2015, we enrolled 73 cases of children with cardiac insufficiency for this study, and all 73 were placed in the observation group. 76 normal cases were selected for the control group. Restriction fragment length polymorphism (RFLP) was used to make polymorphism analysis of the Mink-S27. Our results showed no significant differences in Mink-S27 genotype and allele distribution in both observation and control groups (p>0.05). In lesion samples collected from children with cardiac insufficiency, we detected significant difference in AA, CC genotype frequency and allele frequency between the observation group and the control group (p< 0.05) (X2 = 15.43, p<0.05; X2  = 16.27, p<0.05). Further studies on samples obtained from both groups revealed certain differences of AA, CC, AC genotype frequency and allele frequency in the observation group. The proportion of homozygote (AA, CC) in children with severe cardiac insufficiency was relatively high. GNAS2 gene polymorphism was associated with the prevalence of cardiac insufficiency in children. And also the patients' condition was correlated to the frequency of different genotypes and alleles.

Analyzing self-controlled case series data when case confirmation rates are estimated from an internal validation sample.

PubMed

Xu, Stanley; Clarke, Christina L; Newcomer, Sophia R; Daley, Matthew F; Glanz, Jason M

2018-05-16

Vaccine safety studies are often electronic health record (EHR)-based observational studies. These studies often face significant methodological challenges, including confounding and misclassification of adverse event. Vaccine safety researchers use self-controlled case series (SCCS) study design to handle confounding effect and employ medical chart review to ascertain cases that are identified using EHR data. However, for common adverse events, limited resources often make it impossible to adjudicate all adverse events observed in electronic data. In this paper, we considered four approaches for analyzing SCCS data with confirmation rates estimated from an internal validation sample: (1) observed cases, (2) confirmed cases only, (3) known confirmation rate, and (4) multiple imputation (MI). We conducted a simulation study to evaluate these four approaches using type I error rates, percent bias, and empirical power. Our simulation results suggest that when misclassification of adverse events is present, approaches such as observed cases, confirmed case only, and known confirmation rate may inflate the type I error, yield biased point estimates, and affect statistical power. The multiple imputation approach considers the uncertainty of estimated confirmation rates from an internal validation sample, yields a proper type I error rate, largely unbiased point estimate, proper variance estimate, and statistical power. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

National occupant protection use survey 1996 : controlled intersection study

DOT National Transportation Integrated Search

1997-08-01

In 1996, the overall observed shoulder belt use rate was 61.5%, as measured by the National Occupant Protection Use Survey (NOPUS). This is compared to 58.0% observed in 1994. The NOPUS was conducted in the Fall of 1996 to estimate safety belt use in...

Are parent-reported outcomes for self-directed or telephone-assisted behavioral family intervention enhanced if parents are observed?

PubMed

Morawska, Alina; Sanders, Matthew R

2007-05-01

The study examined the effects of conducting observations as part of a broader assessment of families participating in behavior family intervention (BFI). It was designed to investigate whether the observations improve intervention outcomes. Families were randomly assigned to different levels of BFI or a waitlist control condition and subsequently randomly assigned to either observation or no-observation conditions. This study demonstrated significant intervention and observation effects. Mothers in more intensive BFI reported more improvement in their child's behavior and their own parenting. Observed mothers reported lower intensity of child behavior problems and more effective parenting styles. There was also a trend for less anger among mothers who were observed and evidence of an observation-intervention interaction for parental anger, with observed mothers in more intensive intervention reporting less anger compared to those not observed. Implications for clinical and research intervention contexts are discussed.

Empirical performance of the calibrated self-controlled cohort analysis within temporal pattern discovery: lessons for developing a risk identification and analysis system.

PubMed

Norén, G Niklas; Bergvall, Tomas; Ryan, Patrick B; Juhlin, Kristina; Schuemie, Martijn J; Madigan, David

2013-10-01

Observational healthcare data offer the potential to identify adverse drug reactions that may be missed by spontaneous reporting. The self-controlled cohort analysis within the Temporal Pattern Discovery framework compares the observed-to-expected ratio of medical outcomes during post-exposure surveillance periods with those during a set of distinct pre-exposure control periods in the same patients. It utilizes an external control group to account for systematic differences between the different time periods, thus combining within- and between-patient confounder adjustment in a single measure. To evaluate the performance of the calibrated self-controlled cohort analysis within Temporal Pattern Discovery as a tool for risk identification in observational healthcare data. Different implementations of the calibrated self-controlled cohort analysis were applied to 399 drug-outcome pairs (165 positive and 234 negative test cases across 4 health outcomes of interest) in 5 real observational databases (four with administrative claims and one with electronic health records). Performance was evaluated on real data through sensitivity/specificity, the area under receiver operator characteristics curve (AUC), and bias. The calibrated self-controlled cohort analysis achieved good predictive accuracy across the outcomes and databases under study. The optimal design based on this reference set uses a 360 days surveillance period and a single control period 180 days prior to new prescriptions. It achieved an average AUC of 0.75 and AUC >0.70 in all but one scenario. A design with three separate control periods performed better for the electronic health records database and for acute renal failure across all data sets. The estimates for negative test cases were generally unbiased, but a minor negative bias of up to 0.2 on the RR-scale was observed with the configurations using multiple control periods, for acute liver injury and upper gastrointestinal bleeding. The calibrated self-controlled cohort analysis within Temporal Pattern Discovery shows promise as a tool for risk identification; it performs well at discriminating positive from negative test cases. The optimal parameter configuration may vary with the data set and medical outcome of interest.

Case-control studies in neurosurgery.

PubMed

Nesvick, Cody L; Thompson, Clinton J; Boop, Frederick A; Klimo, Paul

2014-08-01

Observational studies, such as cohort and case-control studies, are valuable instruments in evidence-based medicine. Case-control studies, in particular, are becoming increasingly popular in the neurosurgical literature due to their low cost and relative ease of execution; however, no one has yet systematically assessed these types of studies for quality in methodology and reporting. The authors performed a literature search using PubMed/MEDLINE to identify all studies that explicitly identified themselves as "case-control" and were published in the JNS Publishing Group journals (Journal of Neurosurgery, Journal of Neurosurgery: Pediatrics, Journal of Neurosurgery: Spine, and Neurosurgical Focus) or Neurosurgery. Each paper was evaluated for 22 descriptive variables and then categorized as having either met or missed the basic definition of a case-control study. All studies that evaluated risk factors for a well-defined outcome were considered true case-control studies. The authors sought to identify key features or phrases that were or were not predictive of a true case-control study. Those papers that satisfied the definition were further evaluated using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist. The search detected 67 papers that met the inclusion criteria, of which 32 (48%) represented true case-control studies. The frequency of true case-control studies has not changed with time. Use of odds ratios (ORs) and logistic regression (LR) analysis were strong positive predictors of true case-control studies (for odds ratios, OR 15.33 and 95% CI 4.52-51.97; for logistic regression analysis, OR 8.77 and 95% CI 2.69-28.56). Conversely, negative predictors included focus on a procedure/intervention (OR 0.35, 95% CI 0.13-0.998) and use of the word "outcome" in the Results section (OR 0.23, 95% CI 0.082-0.65). After exclusion of nested case-control studies, the negative correlation between focus on a procedure/intervention and true case-control studies was strengthened (OR 0.053, 95% CI 0.0064-0.44). There was a trend toward a negative association between the use of survival analysis or Kaplan-Meier curves and true case-control studies (OR 0.13, 95% CI 0.015-1.12). True case-control studies were no more likely than their counterparts to use a potential study design "expert" (OR 1.50, 95% CI 0.57-3.95). The overall average STROBE score was 72% (range 50-86%). Examples of reporting deficiencies were reporting of bias (28%), missing data (55%), and funding (44%). The results of this analysis show that the majority of studies in the neurosurgical literature that identify themselves as "case-control" studies are, in fact, labeled incorrectly. Positive and negative predictors were identified. The authors provide several recommendations that may reverse the incorrect and inappropriate use of the term "case-control" and improve the quality of design and reporting of true case-control studies in neurosurgery.

Glucagon-like peptide-1 receptor agonists and heart failure in type 2 diabetes: systematic review and meta-analysis of randomized and observational studies.

PubMed

Li, Ling; Li, Sheyu; Liu, Jiali; Deng, Ke; Busse, Jason W; Vandvik, Per Olav; Wong, Evelyn; Sohani, Zahra N; Bala, Malgorzata M; Rios, Lorena P; Malaga, German; Ebrahim, Shanil; Shen, Jiantong; Zhang, Longhao; Zhao, Pujing; Chen, Qunfei; Wang, Yingqiang; Guyatt, Gordon H; Sun, Xin

2016-05-11

The effect of glucagon-like peptide-1(GLP-1) receptor agonists on heart failure remains uncertain. We therefore conducted a systematic review to assess the possible impact of GLP-1 agonists on heart failure or hospitalization for heart failure in patients with type 2 diabetes. We searched MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL) and ClinicalTrials.gov to identify randomized controlled trials (RCTs) and observational studies that addressed the effect of GLP-1 receptor agonists in adults with type 2 diabetes, and explicitly reported heart failure or hospitalization for heart failure. Two paired reviewers screened reports, collected data, and assessed the risk of bias. We pooled data from RCTs and observational studies separately, and used the GRADE approach to rate the quality of evidence. We identified 25 studies that were eligible for our review; 21 RCTs (n = 18,270) and 4 observational studies (n = 111,029). Low quality evidence from 20 RCTs suggested, if anything, a lower incidence of heart failure between GLP-1 agonists versus control (17/7,441 vs. 19/4,317; odds ratio (OR) 0.62, 95 % confidence interval (CI) 0.31 to 1.22; risk difference (RD) 19 fewer, 95 % CI 34 fewer to 11 more per 1000 over 5 years). Three cohort studies comparing GLP-1 agonists to alternative agents provided very low quality evidence that GLP-1 agonists do not increase the incidence of heart failure. One RCT provided moderate quality evidence that GLP-1 agonists were not associated with hospitalization for heart failure (lixisenatide vs placebo: 122/3,034 vs. 127/3,034; adjusted hazard ratio 0.96, 95 % CI 0.75 to 1.23; RD 4 fewer, 95 % CI 25 fewer to 23 more per 1000 over 5 years) and a case-control study provided very low quality evidence also suggesting no association (GLP-1 agonists vs. other anti-hyperglycemic drugs: 1118 cases and 17,626 controls, adjusted OR 0.67, 95 % CI 0.32 to 1.42). The current evidence suggests that GLP-1 agonists do not increase the risk of heart failure or hospitalization for heart failure among patients with type 2 diabetes.

Effect of Carthamus tinctorius (Safflower) on fasting blood glucose and insulin levels in alloxan induced diabetic rabbits.

PubMed

Qazi, Nasreen; Khan, Rafeeq Alam; Rizwani, Ghazala H; Feroz, Zeeshan

2014-03-01

Diabetes mellitus is a major threat to present and future generations. The role of herbal medication has emerged as a safe alternative to currently available medication due to its decreased potential to produce side effects, hence effect of Carthamus tinctorius was observed on fasting blood glucose and insulin levels in alloxan induced diabetic rabbits. Thirty five healthy male rabbits were divided into 5 groups with 7 rabbits in each (Normal control, diabetic control, diabetic treated with glibenclamide, diabetic treated with Carthamus tinctorius extract at doses of 200 and 300mg/kg of body weight). Drug and extract were given orally for 30 days and the values for blood glucose levels were observed after 15(th) and 30(th) day of treatment by using standard reagent kits provided by Human Germany. While insulin levels were checked at the end of the study by using Architect i1000 by Abbott Diagnostics USA. Animals were also observed for any gross toxicity during the study. Results revealed that Carthamus tinctorius has significant hypoglycemic effect at 200mg/kg and 300mg/kg doses as compared to diabetic control group. Insulin levels were significantly increased in Glibenclamide treated as well as Carthamus tinctorius treated groups as compared to diabetic control.

Self-other resonance, its control and prosocial inclinations: Brain-behavior relationships.

PubMed

Christov-Moore, Leonardo; Iacoboni, Marco

2016-04-01

Humans seem to place a positive reward value on prosocial behavior. Evidence suggests that this prosocial inclination is driven by our reflexive tendency to share in the observed sensations, emotions and behavior of others, or "self-other resonance". In this study, we examine how neural correlates of self-other resonance relate to prosocial decision-making. Subjects performed two tasks while undergoing fMRI: observation of a human hand pierced by a needle, and observation and imitation of emotional facial expressions. Outside the scanner, subjects played the Dictator Game with players of low or high income (represented by neutral-expression headshots). Subjects' offers in the Dictator Game were correlated with activity in neural systems associated with self-other resonance and anticorrelated with activity in systems implicated in the control of pain, affect, and imitation. Functional connectivity between areas involved in self-other resonance and top-down control was negatively correlated with subjects' offers. This study suggests that the interaction between self-other resonance and top-down control processes are an important component of prosocial inclinations towards others, even when biological stimuli associated with self-other resonance are limited. These findings support a view of prosocial decision-making grounded in embodied cognition. © 2016 Wiley Periodicals, Inc.

Allergies and risk of head and neck cancer: an original study plus meta-analysis.

PubMed

Hsiao, Jenn-Ren; Ou, Chun-Yen; Lo, Hung-I; Huang, Cheng-Chih; Lee, Wei-Ting; Huang, Jehn-Shyun; Chen, Ken-Chung; Wong, Tung-Yiu; Tsai, Sen-Tien; Yen, Chia-Jui; Wu, Yuan-Hua; Hsueh, Wei-Ting; Yang, Ming-Wei; Wu, Shang-Yin; Chang, Jang-Yang; Chang, Kwang-Yu; Lin, Chen-Lin; Wang, Fang-Ting; Wang, Yi-Hui; Weng, Ya-Ling; Yang, Han-Chien; Chang, Jeffrey S

2013-01-01

Although the relationship between allergy and cancer has been investigated extensively, the role of allergy in head and neck cancer (HNC) appears less consistent. It is not clear whether allergies can independently influence the risk of HNC in the presence of known strong environmental risk factors, including consumption of alcohol, betel quid, and cigarette. THE CURRENT PAPER REPORTS RESULTS FROM: 1) an original hospital-based case-control study, which included 252 incident cases of HNC and 236 controls frequency-matched to cases on sex and age; and 2) a meta-analysis combining the results of the current case-control study and 13 previously published studies (9 cohort studies with 727,569 subjects and 550 HNC outcomes and 5 case-control studies with 4,017 HNC cases and 10,928 controls). In the original case-control study, we observed a strong inverse association between allergies and HNC [odds ratio = 0.41, 95% confidence interval (CI): 0.27-0.62]. The meta-analysis also indicated a statistically significant inverse association between HNC and allergies [meta-relative risk (RR) = 0.76, 95% CI: 0.63-0.91], particularly strong for allergic rhinitis (meta-RR = 0.55, 95% CI: 0.40-0.76). In addition, the inverse association between allergies and HNC was observed only among men (meta-RR = 0.67, 95% CI: 0.54-0.84) but not among women (meta-RR = 0.98, 95% CI: 0.81-1.18). These findings suggest that immunity plays an influential role in the risk of HNC. Future studies investigating immune biomarkers, including cytokine profiles and genetic polymorphisms, are warranted to further delineate the relationship between allergies and HNC. Understanding the relationship between allergies and HNC may help devise effective strategies to reduce and treat HNC.

Integrating data from randomized controlled trials and observational studies to predict the response to pregabalin in patients with painful diabetic peripheral neuropathy.

PubMed

Alexander, Joe; Edwards, Roger A; Savoldelli, Alberto; Manca, Luigi; Grugni, Roberto; Emir, Birol; Whalen, Ed; Watt, Stephen; Brodsky, Marina; Parsons, Bruce

2017-07-20

More patient-specific medical care is expected as more is learned about variations in patient responses to medical treatments. Analytical tools enable insights by linking treatment responses from different types of studies, such as randomized controlled trials (RCTs) and observational studies. Given the importance of evidence from both types of studies, our goal was to integrate these types of data into a single predictive platform to help predict response to pregabalin in individual patients with painful diabetic peripheral neuropathy (pDPN). We utilized three pivotal RCTs of pregabalin (398 North American patients) and the largest observational study of pregabalin (3159 German patients). We implemented a hierarchical cluster analysis to identify patient clusters in the Observational Study to which RCT patients could be matched using the coarsened exact matching (CEM) technique, thereby creating a matched dataset. We then developed autoregressive moving average models (ARMAXs) to estimate weekly pain scores for pregabalin-treated patients in each cluster in the matched dataset using the maximum likelihood method. Finally, we validated ARMAX models using Observational Study patients who had not matched with RCT patients, using t tests between observed and predicted pain scores. Cluster analysis yielded six clusters (287-777 patients each) with the following clustering variables: gender, age, pDPN duration, body mass index, depression history, pregabalin monotherapy, prior gabapentin use, baseline pain score, and baseline sleep interference. CEM yielded 1528 unique patients in the matched dataset. The reduction in global imbalance scores for the clusters after adding the RCT patients (ranging from 6 to 63% depending on the cluster) demonstrated that the process reduced the bias of covariates in five of the six clusters. ARMAX models of pain score performed well (R 2 : 0.85-0.91; root mean square errors: 0.53-0.57). t tests did not show differences between observed and predicted pain scores in the 1955 patients who had not matched with RCT patients. The combination of cluster analyses, CEM, and ARMAX modeling enabled strong predictive capabilities with respect to pain scores. Integrating RCT and Observational Study data using CEM enabled effective use of Observational Study data to predict patient responses.

Randomized Trials Built on Sand: Examples from COPD, Hormone Therapy, and Cancer

PubMed Central

Suissa, Samy

2012-01-01

The randomized controlled trial is the fundamental study design to evaluate the effectiveness of medications and receive regulatory approval. Observational studies, on the other hand, are essential to address post-marketing drug safety issues but have also been used to uncover new indications or new benefits for already marketed drugs. Hormone replacement therapy (HRT) for instance, effective for menopausal symptoms, was reported in several observational studies during the 1980s and 1990s to also significantly reduce the incidence of coronary heart disease. This claim was refuted in 2002 by the large-scale Women’s Health Initiative randomized trial. An example of a new indication for an old drug is that of metformin, an anti-diabetic medication, which is being hailed as a potential anti-cancer agent, primarily on the basis of several recent observational studies that reported impressive reductions in cancer incidence and mortality with its use. These observational studies have now sparked the conduct of large-scale randomized controlled trials currently ongoing in cancer. We show in this paper that the spectacular effects on new indications or new outcomes reported in many observational studies in chronic obstructive pulmonary disease (COPD), HRT, and cancer are the result of time-related biases, such as immortal time bias, that tend to seriously exaggerate the benefits of a drug and that eventually disappear with the proper statistical analysis. In all, while observational studies are central to assess the effects of drugs, their proper design and analysis are essential to avoid bias. The scientific evidence on the potential beneficial effects in new indications of existing drugs will need to be more carefully assessed before embarking on long and expensive unsubstantiated trials. PMID:23908838

A detailed observation of the ejection and retraction of defense tissue acontia in sea anemone (Exaiptasia pallida).

PubMed

Lam, Julie; Cheng, Ya-Wen; Chen, Wan-Nan U; Li, Hsing-Hui; Chen, Chii-Shiarng; Peng, Shao-En

2017-01-01

Acontia, located in the gastrovascular cavity of anemone, are thread-like tissue containing numerous stinging cells which serve as a unique defense tissue against predators of the immobile acontiarian sea anemone. Although its morphology and biological functions, such as defense and digestion, have been studied, the defense behavior and the specific events of acontia ejection and retraction are unclear. The aim of this study is to observe and record the detailed process of acontia control in anemones. Observations reveal that the anemone, Exaiptasia pallida , possibly controls a network of body muscles and manipulates water pressure in the gastrovascular cavity to eject and retract acontia. Instead of resynthesizing acontia after each ejection, the retraction and reuse of acontia enables the anemone to respond quickly at any given time, thus increasing its overall survivability. Since the Exaiptasia anemone is an emerging model for coral biology, this study provides a foundation to further investigate the biophysics, neuroscience, and defense biology of this marine model organism.

A detailed observation of the ejection and retraction of defense tissue acontia in sea anemone (Exaiptasia pallida)

PubMed Central

Lam, Julie; Cheng, Ya-Wen; Chen, Wan-Nan U.; Li, Hsing-Hui; Chen, Chii-Shiarng

2017-01-01

Acontia, located in the gastrovascular cavity of anemone, are thread-like tissue containing numerous stinging cells which serve as a unique defense tissue against predators of the immobile acontiarian sea anemone. Although its morphology and biological functions, such as defense and digestion, have been studied, the defense behavior and the specific events of acontia ejection and retraction are unclear. The aim of this study is to observe and record the detailed process of acontia control in anemones. Observations reveal that the anemone, Exaiptasia pallida, possibly controls a network of body muscles and manipulates water pressure in the gastrovascular cavity to eject and retract acontia. Instead of resynthesizing acontia after each ejection, the retraction and reuse of acontia enables the anemone to respond quickly at any given time, thus increasing its overall survivability. Since the Exaiptasia anemone is an emerging model for coral biology, this study provides a foundation to further investigate the biophysics, neuroscience, and defense biology of this marine model organism. PMID:28243530

Study on clinical effect and immunologic mechanism of infants capillary bronchitis secondary bronchial asthma treated with bacterial lysates Broncho-Vaxom.

PubMed

Han, R-F; Li, H-Y; Wang, J-W; Cong, X-J

2016-05-01

To study the clinical effects and immunologic mechanism of infant capillary bronchitis secondary bronchial asthma treated with bacterial lysates (Broncho-Vaxom OM-85BV). Between February 2013 and February 2014, 136 infant capillary bronchitis secondary bronchial asthma cases were chosen. This research was approved by Ethics Committee in our hospital and obtained the informed consent right from patients and guardians. Patients were divided into the control group (n = 62) and the observation group (n = 74) using random number table method. Patients in the control group were treated with normal glucocorticoid atomizing inhalation, aminophylline and antibiotic treatment. In the observation group besides the abovementioned treatment, we added Broncho-Vaxom OM-85BV, qd po for 10 days continuously and quitted it for 20 days. This continued for a total of 3 months. Follow-ups were set for about one year to compare the effects. The onset frequency and duration of capillary bronchitis and asthma in observation group declined remarkably compared with control group and the differences were statistically significant (p < 0.05). The level of IL-17 and IL-4 in the observation group decreased significantly, whereas, the level of IL-10 and IFN- γ increased considerably. Differences were all statistically significant (p < 0.05). Peripheral blood CD4+ T lymphocytes in the observation group patients expressed lower levels of nicotinic acetylcholine receptors α7 (α7nAChR) compared to the control group. Then difference was statistically significant (p < 0.05). Broncho-Vaxom OM-85BV reduced the onset of infant capillary bronchitis secondary bronchial asthma, relating to the reduced inflammation reaction. It also regulated the immunologic function of Th1/Th2, and lowered the α7nAChR level.

A New Strategy in Observer Modeling for Greenhouse Cucumber Seedling Growth

PubMed Central

Qiu, Quan; Zheng, Chenfei; Wang, Wenping; Qiao, Xiaojun; Bai, He; Yu, Jingquan; Shi, Kai

2017-01-01

State observer is an essential component in computerized control loops for greenhouse-crop systems. However, the current accomplishments of observer modeling for greenhouse-crop systems mainly focus on mass/energy balance, ignoring physiological responses of crops. As a result, state observers for crop physiological responses are rarely developed, and control operations are typically made based on experience rather than actual crop requirements. In addition, existing observer models require a large number of parameters, leading to heavy computational load and poor application feasibility. To address these problems, we present a new state observer modeling strategy that takes both environmental information and crop physiological responses into consideration during the observer modeling process. Using greenhouse cucumber seedlings as an instance, we sample 10 physiological parameters of cucumber seedlings at different time point during the exponential growth stage, and employ them to build growth state observers together with 8 environmental parameters. Support vector machine (SVM) acts as the mathematical tool for observer modeling. Canonical correlation analysis (CCA) is used to select the dominant environmental and physiological parameters in the modeling process. With the dominant parameters, simplified observer models are built and tested. We conduct contrast experiments with different input parameter combinations on simplified and un-simplified observers. Experimental results indicate that physiological information can improve the prediction accuracies of the growth state observers. Furthermore, the simplified observer models can give equivalent or even better performance than the un-simplified ones, which verifies the feasibility of CCA. The current study can enable state observers to reflect crop requirements and make them feasible for applications with simplified shapes, which is significant for developing intelligent greenhouse control systems for modern greenhouse production. PMID:28848565

A New Strategy in Observer Modeling for Greenhouse Cucumber Seedling Growth.

PubMed

Qiu, Quan; Zheng, Chenfei; Wang, Wenping; Qiao, Xiaojun; Bai, He; Yu, Jingquan; Shi, Kai

2017-01-01

State observer is an essential component in computerized control loops for greenhouse-crop systems. However, the current accomplishments of observer modeling for greenhouse-crop systems mainly focus on mass/energy balance, ignoring physiological responses of crops. As a result, state observers for crop physiological responses are rarely developed, and control operations are typically made based on experience rather than actual crop requirements. In addition, existing observer models require a large number of parameters, leading to heavy computational load and poor application feasibility. To address these problems, we present a new state observer modeling strategy that takes both environmental information and crop physiological responses into consideration during the observer modeling process. Using greenhouse cucumber seedlings as an instance, we sample 10 physiological parameters of cucumber seedlings at different time point during the exponential growth stage, and employ them to build growth state observers together with 8 environmental parameters. Support vector machine (SVM) acts as the mathematical tool for observer modeling. Canonical correlation analysis (CCA) is used to select the dominant environmental and physiological parameters in the modeling process. With the dominant parameters, simplified observer models are built and tested. We conduct contrast experiments with different input parameter combinations on simplified and un-simplified observers. Experimental results indicate that physiological information can improve the prediction accuracies of the growth state observers. Furthermore, the simplified observer models can give equivalent or even better performance than the un-simplified ones, which verifies the feasibility of CCA. The current study can enable state observers to reflect crop requirements and make them feasible for applications with simplified shapes, which is significant for developing intelligent greenhouse control systems for modern greenhouse production.

Turbulent Flow Modification With Thermoacoustic Waves for Separation Control

DTIC Science & Technology

2017-08-24

analyses using two different approaches in order to provide guidance to physics-based design of active flow control using thermal-based actuators. RPPR... control effects are also observed by Post & Corke (2004) on the same airfoil. The uses of plasma actuators on other shear layer setups have been...region may be a more practical approach than introducing control inputs externally. On the other hand, Barone & Lele (2005) studied the receptivity of the

Alterations in diurnal rhythmicity in patients treated for nonfunctioning pituitary macroadenoma: a controlled study and literature review.

PubMed

Joustra, S D; Thijs, R D; van den Berg, R; van Dijk, M; Pereira, A M; Lammers, G J; van Someren, E J W; Romijn, J A; Biermasz, N R

2014-08-01

Patients treated for nonfunctioning pituitary macroadenomas (NFMAs) have fatigue and alterations in sleep characteristics and sleep-wake rhythmicity frequently. As NFMAs often compress the optic chiasm, these complaints might be related to dysfunction of the adjacent suprachiasmatic nucleus (SCN). We aimed to explore whether indirect indices of SCN functioning are altered in the long term after surgery for NFMAs. We studied 17 NFMA patients in long-term remission after transsphenoidal surgery, receiving adequate and stable hormone replacement for hypopituitarism, and 17 control subjects matched for age, gender, and BMI. Indirect indices of SCN function were assessed from 24-h ambulatory recordings of skin and core body temperatures, blood pressure, and salivary melatonin levels. Altered melatonin secretion was defined as an absence of evening rise, considerable irregularity, or daytime values >3 pg/ml. We additionally studied eight patients treated for craniopharyngioma. Distal-proximal skin temperature gradient did not differ between NFMAs and control subjects, but proximal skin temperature was decreased during daytime (P=0.006). Core body temperature and non-dipping of blood pressure did not differ, whereas melatonin secretion was often altered in NFMAs (OR 5.3, 95% CI 0.9-30.6). One or more abnormal parameters (≥2.0 SDS of control subjects) were observed during nighttime in 12 NFMA patients and during daytime in seven NFMA patients. Similar patterns were observed in craniopharyngioma patients. Heterogeneous patterns of altered diurnal rhythmicity in skin temperature and melatonin secretion parameters were observed in the majority of patients treated for NFMAs. On a group level, both NFMA and craniopharyngioma patients showed a lower daytime proximal skin temperature than control subjects, but other group averages were not significantly different. The observations suggest altered function of central (or peripheral) clock machinery, possibly by disturbed entrainment or damage of the hypothalamic SCN by the suprasellar macroadenoma or its treatment. © 2014 European Society of Endocrinology.

Body mass index and risk of BPH: a meta-analysis.

PubMed

Wang, S; Mao, Q; Lin, Y; Wu, J; Wang, X; Zheng, X; Xie, L

2012-09-01

Epidemiological studies have reported conflicting results relating obesity to BPH. A meta-analysis of cohort and case-control studies was conducted to pool the risk estimates of the association between obesity and BPH. Eligible studies were retrieved by both computer searches and review of references. We analyzed abstracted data with random effects models to obtain the summary risk estimates. Dose-response meta-analysis was performed for studies reporting categorical risk estimates for a series of exposure levels. A total of 19 studies met the inclusion criteria of the meta-analysis. Positive association with body mass index (BMI) was observed in BPH and lower urinary tract symptoms (LUTS) combined group (odds ratio=1.27, 95% confidence intervals 1.05-1.53). In subgroup analysis, BMI exhibited a positive dose-response relationship with BPH/LUTS in population-based case-control studies and a marginal positive association was observed between risk of BPH and increased BMI. However, no association between BPH/LUTS and BMI was observed in other subgroups stratified by study design, geographical region or primary outcome. The overall current literatures suggested that BMI was associated with increased risk of BPH. Further efforts should be made to confirm these findings and clarify the underlying biological mechanisms.

Descemet Membrane Thickening as a Sign for the Diagnosis of Corneal Graft Rejection: An Ex Vivo Study.

PubMed

VanDenBerg, Ryan; Diakonis, Vasilios F; Bozung, Alison; Gameiro, Gustavo Rosa; Fischer, Oliver; El Dakkak, Ahmed; Ulloa-Padilla, Jan Paul; Anagnostopoulos, Apostolos; Dubovy, Sander; Abou Shousha, Mohamed

2017-12-01

To disclose, using an ex vivo study, the histopathological mechanism behind in vivo thickening of the endothelium/Descemet membrane complex (En/DM) observed in rejected corneal grafts (RCGs). Descemet membrane (DM), endothelium, and retrocorneal membranes make up the total En/DM thickness. These layers are not differentiable by high-definition optical coherence tomography; therefore, the source of thickening is unclear from an in vivo perspective. A retrospective ex vivo study (from September 2015 to December 2015) was conducted to measure the thicknesses of DM, endothelium, and retrocorneal membrane in 54 corneal specimens (31 RCGs and 23 controls) using light microscopy. Controls were globes with posterior melanoma without corneal involvement. There were 54 corneas examined ex vivo with mean age 58.1 ± 12.2 in controls and 51.7 ± 27.9 years in RCGs. The ex vivo study uncovered the histopathological mechanism of En/DM thickening to be secondary to significant thickening (P < 0.001) of DM (6.5 ± 2.4 μm) in RCGs compared with controls (3.9 ± 1.5 μm). Our ex vivo study shows that DM is responsible for thickening of the En/DM in RCGs observed in vivo by high-definition optical coherence tomography and not the endothelium or retrocorneal membrane.

Designing electrical stimulated bioreactors for nerve tissue engineering

NASA Astrophysics Data System (ADS)

Sagita, Ignasius Dwi; Whulanza, Yudan; Dhelika, Radon; Nurhadi, Ibrahim

2018-02-01

Bioreactor provides a biomimetic ecosystem that is able to culture cells in a physically controlled system. In general, the controlled-parameters are temperature, pH, fluid flow, nutrition flow, etc. In this study, we develop a bioreactor that specifically targeted to culture neural stem cells. This bioreactor could overcome some limitations of conventional culture technology, such as petri dish, by providing specific range of observation area and a uniform treatment. Moreover, the microfluidic bioreactor, which is a small-controlled environment, is able to observe as small number of cells as possible. A perfusion flow is applied to mimic the physiological environment in human body. Additionally, this bioreactor also provides an electrical stimulation which is needed by neural stem cells. In conclusion, we found the correlation between the induced shear stress with geometric parameters of the bioreactor. Ultimately, this system shall be used to observe the interaction between stimulation and cell growth.

How is the weather? Forecasting inpatient glycemic control

PubMed Central

Saulnier, George E; Castro, Janna C; Cook, Curtiss B; Thompson, Bithika M

2017-01-01

Aim: Apply methods of damped trend analysis to forecast inpatient glycemic control. Method: Observed and calculated point-of-care blood glucose data trends were determined over 62 weeks. Mean absolute percent error was used to calculate differences between observed and forecasted values. Comparisons were drawn between model results and linear regression forecasting. Results: The forecasted mean glucose trends observed during the first 24 and 48 weeks of projections compared favorably to the results provided by linear regression forecasting. However, in some scenarios, the damped trend method changed inferences compared with linear regression. In all scenarios, mean absolute percent error values remained below the 10% accepted by demand industries. Conclusion: Results indicate that forecasting methods historically applied within demand industries can project future inpatient glycemic control. Additional study is needed to determine if forecasting is useful in the analyses of other glucometric parameters and, if so, how to apply the techniques to quality improvement. PMID:29134125

Optical Verification of Microbubble Response to Acoustic Radiation Force in Large Vessels with In Vivo Results

PubMed Central

Wang, Shiying; Wang, Claudia Y.; Unnikrishnan, Sunil; Klibanov, Alexander L.; Hossack, John A.; Mauldin, F. William

2015-01-01

Objectives To optically verify the dynamic behaviors of adherent microbubbles in large blood vessel environments in response to a new ultrasound technique using modulated acoustic radiation force. Materials and Methods Polydimethylsiloxane (PDMS) flow channels coated with streptavidin were used in targeted groups to mimic large blood vessels. The custom modulated acoustic radiation force beam sequence was programmed on a Verasonics research scanner. In vitro experiments were performed by injecting a biotinylated lipid-perfluorobutane microbubble dispersion through flow channels. The dynamic response of adherent microbubbles was detected acoustically and simultaneously visualized using a video camera connected to a microscope. In vivo verification was performed in a large abdominal blood vessel of a murine model for inflammation with injection of biotinylated microbubbles conjugated with P-selectin antibody. Results Aggregates of adherent microbubbles were observed optically under the influence of acoustic radiation force. Large microbubble aggregates were observed solely in control groups without targeted adhesion. Additionally, the dispersion of microbubble aggregates were demonstrated to lead to a transient acoustic signal enhancement in control groups (a new phenomenon we refer to as “control peak”). In agreement with in vitro results, the “control peak” phenomenon was observed in vivo in a murine model. Conclusions This study provides the first optical observation of microbubble binding dynamics in large blood vessel environments with application of a modulated acoustic radiation force beam sequence. With targeted adhesion, secondary radiation forces were unable to produce large aggregates of adherent microbubbles. Additionally, the new phenomenon called “control peak” was observed both in vitro and in vivo in a murine model for the first time. The findings in this study provide us with a better understanding of microbubble behaviors in large blood vessel environments with application of acoustic radiation force, and could potentially guide future beam sequence designs or signal processing routines for enhanced ultrasound molecular imaging. PMID:26135018

Clinical therapeutic effects of AO/ASIF clavicle hook plate on distal clavicle fractures and acromioclavicular joint dislocations.

PubMed

Dou, Qingjun; Ren, Xiaofeng

2014-07-01

The aim of this study was to evaluate the security and effectiveness of AO/ASIF clavicle hook plate in the treatment of distal clavicle fractures and acromioclavicular joint dislocations. One hundred patients with distal clavicle fractures and acromioclavicular joint dislocations who were admitted in our hospital from January 2012 to January 2013 were selected as the study subjects. They were then randomly divided into a control group and an observation group (n=50). The observation group was treated with AO/ASIF clavicle hook plates, and the control group was treated with Kirschner-wire tension bands. The outcomes were recorded and compared. The JOA scores of the two groups were similar before surgery (P>0.05). The two groups both had obviously increased JOA scores in the postoperative 6th and 12th weeks, and the score in the postoperative 12th week was higher. There were statistically significant intra-group differences (P<0.05). The postoperative 6th-week and 12th-week JOA scores of the observation group were (83.2±1.8) and (97.4±1.5) respectively, and those of the control group were (71.6±2.2) and (82.3±2.6) respectively, with statistically significant inter-group differences (P<0.05). Significantly more patients in the observation group (100%) were evaluated as excellent or good outcomes after fixation than those in the control group (60%). After removal of the surgical apparatus, the recurrence rates of bone fracture and joint dislocation in the observation group were significantly lower than those of the control group (P<0.05). AO/ASIF clavicle hook plate functioned more effectively than Kirschner-wire tension band in clinical treatment of distal clavicle fractures and acromioclavicular joint dislocations. The former protocol enjoyed small incisions, firm fixation and early shoulder mobility. Therefore, it is a safe and effective surgical method that is worthy of being widely applied in clinical practice.

Hair cortisol and dehydroepiandrosterone concentrations in naturally Taenia solium infected pigs in Tanzania.

PubMed

Trevisan, Chiara; Montillo, Marta; Prandi, Alberto; Mkupasi, Ernatus M; Ngowi, Helena A; Johansen, Maria V

2017-05-15

The aim of this study was to measure hair cortisol and dehydroepiandrosterone (DHEA) concentrations in naturally Taenia solium infected and non-infected control pigs and assess the effect of an environmental change on the aforementioned parameters. Three hair patches were obtained from 13 T. solium infected and 15 non-infected controls sows, respectively corresponding to 3 time points (prior to, at and approximately two weeks after arrival at the research facility). Cortisol and DHEA were extracted using methanol and analysed by radio immune assay. Mean hair cortisol concentrations were significantly lower (p<0.001) in T. solium infected (4.7±3.0pg/mg) compared to control pigs (9.0±3.7pg/mg) prior to arrival at the research facility, however no significant difference was observed between the two groups at arrival and after approximately two weeks. Similar patterns were also observed for DHEA concentrations (infected pigs 253.9±82.3pg/mg, control pigs 387.7±116.4pg/mg) (p<0.001). Results showed that lean animals had significantly higher cortisol concentrations in both groups, infected and controls pigs, while DHEA was not significantly different between lean and normal animals. Results of this study have shown that an environmental change could have an effect on pigs' hormonal levels suggesting an undergoing adaptation process. After the pigs were kept under the same conditions, fed and watered ad libitum, no significant differences were observed between the groups, but a drop in DHEA concentrations was observed in all the pigs. Weight however had an effect on cortisol levels as lean animals had significantly higher cortisol concentrations in both groups, compared to normal pigs. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Observability and Controllability of Networks: Symmetry in Representations of Brains and Controllers for Epidemics

NASA Astrophysics Data System (ADS)

Schiff, Steven

Observability and controllability are essential concepts to the design of predictive observer models and feedback controllers of networked systems. We present a numerical and group representational framework, to quantify the observability and controllability of nonlinear networks with explicit symmetries that shows the connection between symmetries and nonlinear measures of observability and controllability. In addition to the topology of brain networks, we have advanced our ability to represent network nodes within the brain using conservation principles and more accurate biophysics that unifies the dynamics of spikes, seizures, and spreading depression. Lastly, we show how symmetries in controller design can be applied to infectious disease epidemics. NIH Grants 1R01EB014641, 1DP1HD086071.

Impact of hospitalizations for bronchiolitis in preterm infants on long-term health care costs in Italy: a retrospective case-control study.

PubMed

Roggeri, Daniela Paola; Roggeri, Alessandro; Rossi, Elisa; Cataudella, Salvatore; Martini, Nello

2016-01-01

Bronchiolitis is an acute inflammatory injury of the bronchioles, and is the most frequent cause of hospitalization for lower respiratory tract infections in preterm infants. This was a retrospective, observational, case-control study conducted in Italy, based on administrative database analysis. The aim of this study was to evaluate differences in health care costs of preterm infants with and without early hospitalization for bronchiolitis. Preterm infants born in the period between January 1, 2009 and December 31, 2010 and hospitalized for bronchiolitis in the first year of life were selected from the ARNO Observatory database and observed for the first 4 years of life. These preterm infants were compared (paired 1-3) with preterm infants who were not hospitalized for bronchiolitis in the first year of life and with similar characteristics. Only direct health care costs reimbursed by the Italian National Health Service were considered for this study (drugs, hospitalizations, and diagnostic/therapeutic procedures). Of 40,823 newborns in the accrual period, 863 were preterm with no evidence of prophylaxis, and 22 preterm infants were hospitalized for bronchiolitis (cases) and paired with 62 controls. Overall, cases had 74% higher average cost per infant in the first 4 years of life than controls (18,624€ versus 10,189€, respectively). The major cost drivers were hospitalizations, accounting for >90% in both the populations. The increase in total yearly health care cost between cases and controls remained substantial even in the fourth year of life for all cost items. A relevant increase in hospitalizations and drug consumption linked to respiratory tract diseases was noted in infants hospitalized for bronchiolitis during the entire follow-up period. Preterm infants hospitalized for bronchiolitis in the first year of life were associated with increased resource consumption and costs throughout the entire period of observation; even in the fourth year, the difference versus paired controls was relevant.

Aerosol delivery with two ventilation modes during mechanical ventilation: a randomized study.

PubMed

Dugernier, Jonathan; Reychler, Gregory; Wittebole, Xavier; Roeseler, Jean; Depoortere, Virginie; Sottiaux, Thierry; Michotte, Jean-Bernard; Vanbever, Rita; Dugernier, Thierry; Goffette, Pierre; Docquier, Marie-Agnes; Raftopoulos, Christian; Hantson, Philippe; Jamar, François; Laterre, Pierre-François

2016-12-01

Volume-controlled ventilation has been suggested to optimize lung deposition during nebulization although promoting spontaneous ventilation is targeted to avoid ventilator-induced diaphragmatic dysfunction. Comparing topographic aerosol lung deposition during volume-controlled ventilation and spontaneous ventilation in pressure support has never been performed. The aim of this study was to compare lung deposition of a radiolabeled aerosol generated with a vibrating-mesh nebulizer during invasive mechanical ventilation, with two modes: pressure support ventilation and volume-controlled ventilation. Seventeen postoperative neurosurgery patients without pulmonary disease were randomly ventilated in pressure support or volume-controlled ventilation. Diethylenetriaminepentaacetic acid labeled with technetium-99m (2 mCi/3 mL) was administrated using a vibrating-mesh nebulizer (Aerogen Solo(®), provided by Aerogen Ltd, Galway, Ireland) connected to the endotracheal tube. Pulmonary and extrapulmonary particles deposition was analyzed using planar scintigraphy. Lung deposition was 10.5 ± 3.0 and 15.1 ± 5.0 % of the nominal dose during pressure support and volume-controlled ventilation, respectively (p < 0.05). Higher endotracheal tube and tracheal deposition was observed during pressure support ventilation (27.4 ± 6.6 vs. 20.7 ± 6.0 %, p < 0.05). A similar penetration index was observed for the right (p = 0.210) and the left lung (p = 0.211) with both ventilation modes. A high intersubject variability of lung deposition was observed with both modes regarding lung doses, aerosol penetration and distribution between the right and the left lung. In the specific conditions of the study, volume-controlled ventilation was associated with higher lung deposition of nebulized particles as compared to pressure support ventilation. The clinical benefit of this effect warrants further studies. Clinical trial registration NCT01879488.

Gender-Differentiated Parenting Revisited: Meta-Analysis Reveals Very Few Differences in Parental Control of Boys and Girls

PubMed Central

Endendijk, Joyce J.; Groeneveld, Marleen G.; Bakermans-Kranenburg, Marian J.; Mesman, Judi

2016-01-01

Although various theories describe mechanisms leading to differential parenting of boys and girls, there is no consensus about the extent to which parents do treat their sons and daughters differently. The last meta-analyses on the subject were conducted more than fifteen years ago, and changes in gender-specific child rearing in the past decade are quite plausible. In the current set of meta-analyses, based on 126 observational studies (15,034 families), we examined mothers’ and fathers’ differential use of autonomy-supportive and controlling strategies with boys and girls, and the role of moderators related to the decade in which the study was conducted, the observational context, and sample characteristics. Databases of Web of Science, ERIC, PsychInfo, Online Contents, Picarta, and Proquest were searched for studies examining differences in observed parental control of boys and girls between the ages of 0 and 18 years. Few differences were found in parents’ use of control with boys and girls. Parents were slightly more controlling with boys than with girls, but the effect size was negligible (d = 0.08). The effect was larger, but still small, in normative groups and in samples with younger children. No overall effect for gender-differentiated autonomy-supportive strategies was found (d = 0.03). A significant effect of time emerged: studies published in the 1970s and 1980s reported more autonomy-supportive strategies with boys than toward girls, but from 1990 onwards parents showed somewhat more autonomy-supportive strategies with girls than toward boys. Taking into account parents’ gender stereotypes might uncover subgroups of families where gender-differentiated control is salient, but based on our systematic review of the currently available large data base we conclude that in general the differences between parenting of boys versus girls are minimal. PMID:27416099

Clinical Knowledge from Observational Studies: Everything You Wanted to Know but Were Afraid to Ask.

PubMed

Gershon, Andrea S; Jafarzadeh, S Reza; Wilson, Kevin C; Walkey, Allan J

2018-05-07

Well-done randomized trials provide accurate estimates of treatment effect by producing groups that are similar on all measures except for the intervention of interest. However, inferences of efficacy in tightly-controlled experimental settings may not translate into similar effectiveness in real-world settings. Observational studies generally enable inferences over a wider range of patient characteristics and evaluation of a broader range of outcomes over a longer period than randomized trials. However, clinicians are often reluctant to incorporate the findings of observational studies into clinical practice. Reason for uncertainty regarding observational studies include a lack of familiarity with observational research methods, occasional disagreements between results of observational studies and randomized trials, the perceived risk of spurious results from systematic bias, and prior teaching that randomized trials are the most reliable source of medical evidence. We propose that a better understanding of observational research will enhance clinicians' ability to distinguish reliable observational studies from those that are subjected to biases and, therefore, provide more confidence to apply observational research results into clinical practice when appropriate. Herein, we explain why observational studies may be perceived as less conclusive than randomized trials, address situations in which observational research and randomized trials produced different findings, and provide information on observational study design so that quality can be evaluated. We conclude that observational research is a valuable source of medical evidence and that clinical action is strongest when supported by both high quality observational studies and randomized trials.

Associations between serotonin-related gene polymorphisms and panic disorder.

PubMed

Maron, Eduard; Lang, Aavo; Tasa, Gunnar; Liivlaid, Liivi; Tõru, Innar; Must, Anne; Vasar, Veiko; Shlik, Jakov

2005-06-01

Studies suggest that vulnerability to panic attacks and panic disorder (PD) may be related to a deficient serotonin (5-HT) neurotransmission. In the present case-control study we investigated possible associations between PD phenotype and five candidate polymorphisms including 5-HT transporter (5-HTTLPR and VNTR), monoamine oxidase A (MAOA promoter region), tryptophan hydroxylase 1 (TPH1 218A/C) and 5-HT1B receptor (5-HT1BR 861G/C) genes. The study sample consisted of 158 patients with PD and 215 healthy control subjects. The analysis showed higher frequencies of LL genotype (p = 0.016) and L allele variant (p = 0.007) of 5-HTTLPR in the patients. No significant associations were observed between PD and other candidate gene polymorphisms. However, a higher frequency of longer allele genotypes of the MAOA promoter region was observed in female PD patients with agoraphobia than in female controls (p = 0.016). These findings indicate that genetic variants conceivably related to lower 5-HT neurotransmission may be involved in the development of PD.

Some Insights on Roughness Induced Transition and Control from DNS and Experiments

NASA Astrophysics Data System (ADS)

Suryanarayanan, Saikishan; Ibitayo, Ifeoluwa; Goldstein, David; Brown, Garry

2016-11-01

We study the receptivity and subsequent evolution of an initially laminar flat boundary layer on a flat plate to single and multiple discrete roughness elements (DRE) using a combination of immersed boundary DNS and water channel flow visualization experiments. We examine the transition caused by a single DRE and demonstrate the possibility of suppressing it by an appropriately designed second DRE in both DNS and experiments. The different phases of transition are identified and the roles of Reynolds numbers based on roughness height and boundary layer thickness are investigated. The underlying mechanisms in the observed transition and its control are understood by examining detailed vorticity flux balances. Connections are also made to recent developments in transient growth and streak instability. A unified picture is sought from a parametric study of different DRE dimensions and orientations. The potential applicability of the observations and understanding derived from this study to controlling transition caused by design and environmental roughness over aircraft wings is discussed. Supported by AFOSR # FA9550-15-1-0345.

A new software on TUG-T60 autonomous telescope for astronomical transient events

NASA Astrophysics Data System (ADS)

Dindar, Murat; Helhel, Selçuk; Esenoğlu, Hasan; Parmaksızoğlu, Murat

2015-03-01

Robotic telescopes usually run under the control of a scheduler, which provides high-level control by selecting astronomical targets for observation. TÜBİTAK (Scientific and Technological Research Council of Turkey) National Observatory (TUG)-T60 Robotic Telescope is controlled by open-source OCAAS software, formally named Talon. This study introduces new software which was designed for Talon to catch GRB, GAIA and transient alerts. The new GRB software module (daemon process) alertd is running with all other modules of Talon such as telescoped; focus, dome; camerad and telrun. Maximum slew velocity and acceleration limits of the T60 telescope are enough fast for the GRB and transient observations.

Development of an analytical environmental TEM system and its application.

PubMed

Kishita, Keisuke; Sakai, Hisashi; Tanaka, Hiromochi; Saka, Hiroyasu; Kuroda, Kotaro; Sakamoto, Masayuki; Watabe, Akira; Kamino, Takeo

2009-12-01

Many automotive materials, such as catalysts and fuel cell materials, undergo significant changes in structure or properties when subjected to temperature change or the addition of a gas. For this reason, in the development of these materials, it is important to study the behavior of the material under controlled temperatures and gaseous atmospheres. Recently, a new environmental transmission electron microscope (TEM) has been developed for observation with a high resolution at high temperatures and under gaseous atmospheres, thus making it possible to analyze reaction processes in details. Also, the new TEM provides a high degree of reproducibility of observation conditions, thus making it possible to compare and validate observation of various specimens under a given set of conditions. Furthermore, easiness of gas condition and temperature control can provide a powerful tool for the studying of the mechanism of material change, such as oxidation and reduction reactions.

Disturbance observer-based adaptive sliding mode hybrid projective synchronisation of identical fractional-order financial systems

NASA Astrophysics Data System (ADS)

Khan, Ayub; Tyagi, Arti

2018-05-01

In this paper, we have studied the hybrid projective synchronisation for incommensurate, integer and commensurate fractional-order financial systems with unknown disturbance. To tackle the problem of unknown bounded disturbance, fractional-order disturbance observer is designed to approximate the unknown disturbance. Further, we have introduced simple sliding mode surface and designed adaptive sliding mode controllers incorporating with the designed fractional-order disturbance observer to achieve a bounded hybrid projective synchronisation between two identical fractional-order financial model with different initial conditions. It is shown that the slave system with disturbance can be synchronised with the projection of the master system generated through state transformation. Simulation results are presented to ensure the validity and effectiveness of the proposed sliding mode control scheme in the presence of external bounded unknown disturbance. Also, synchronisation error for commensurate, integer and incommensurate fractional-order financial systems is studied in numerical simulation.

WE-G-217BCD-04: Diagnostic Image Quality Evaluation of a Dedicated Extremity Cone- Beam CT Scanner: Pre-Clinical Studies and First Clinical Results.

PubMed

Muhit, A; Zbijewski, W; Stayman, J; Thawait, G; Yorkston, J; Foos, D; Packard, N; Yang, D; Senn, R; Carrino, J; Siewerdsen, J

2012-06-01

To assess the diagnostic performance of a prototype cone-beam CT (CBCT) scanner developed for musculoskeletal extremity imaging. Studies involved controlled observer studies conducted subsequent to rigorous technical assessment as well as patient images from the first clinical trial in imaging the hand and knee. Performance assessment included: 1.) rigorous technical assessment; 2.) controlled observer studies using CBCT images of cadaveric specimens; and 3.) first clinical images. Technical assessment included measurement of spatial resolution (MTF), constrast, and noise (SDNR) versus kVp and dose using standard CT phantoms. Diagnostic performance in comparison to multi- detector CT (MDCT) was assessed in controlled observer studies involving 12 cadaveric hands and knees scanned with and without abnormality (fracture). Observer studies involved five radiologists rating pertinent diagnostics tasks in 9-point preference and 10-point diagnostic satisfaction scales. Finally, the first clinical images from an ongoing pilot study were assessed in terms of diagnostic utility in disease assessment and overall workflow in patient setup. Quantitative assessment demonstrated sub-mm spatial resolution (MTF exceeding 10% out to 15-20 cm-1) and SDNR sufficient for relevant soft-tissue visualization tasks at dose <10 mGy. Observer studies confirmed optimal acquisition techniques and demonstrated superior utility of combined soft-tissue visualization and isotropic spatial resolution in diagnostic tasks. Images from the patient trial demonstrate exquisite contrast and detail and the ability to detect tissue impingement in weight-bearing exams. The prototype CBCT scanner provides isotropic spatial resolution superior to standard-protocol MDCT with soft-tissue visibility sufficient for a broad range of diagnostic tasks in musculoskeletal radiology. Dosimetry and workflow were advantageous in comparison to whole-body MDCT. Multi-mode and weight-bearing capabilities add valuable functionality. An ongoing clinical study further assesses diagnostic utility and defines the role of such technology in the diagnostic arsenal. - Research Grant, Carestream Health - Research Grant, National Institutes of Health 2R01-CA-112163. © 2012 American Association of Physicists in Medicine.

Association between plant-based diets and plasma lipids: a systematic review and meta-analysis

PubMed Central

Yokoyama, Yoko; Levin, Susan M; Barnard, Neal D

2017-01-01

Abstract Context Although a recent meta-analysis of randomized controlled trials showed that adoption of a vegetarian diet reduces plasma lipids, the association between vegetarian diets and long-term effects on plasma lipids has not been subjected to meta-analysis. Objective The aim was to conduct a systematic review and meta-analysis of observational studies and clinical trials that have examined associations between plant-based diets and plasma lipids. Data Sources MEDLINE, Web of Science, and the Cochrane Central Register of Controlled Trials were searched for articles published in English until June 2015. Study Selection The literature was searched for controlled trials and observational studies that investigated the effects of at least 4 weeks of a vegetarian diet on plasma lipids. Data Extraction Two reviewers independently extracted the study methodology and sample size, the baseline characteristics of the study population, and the concentrations and variance measures of plasma lipids. Mean differences in concentrations of plasma lipids between vegetarian and comparison diet groups were calculated. Data were pooled using a random-effects model. Results Of the 8385 studies identified, 30 observational studies and 19 clinical trials met the inclusion criteria (N = 1484; mean age, 48.6 years). Consumption of vegetarian diets was associated with lower mean concentrations of total cholesterol (−29.2 and −12.5 mg/dL, P < 0.001), low-density lipoprotein cholesterol (−22.9 and −12.2 mg/dL, P < 0.001), and high-density lipoprotein cholesterol (−3.6 and −3.4 mg/dL, P < 0.001), compared with consumption of omnivorous diets in observational studies and clinical trials, respectively. Triglyceride differences were −6.5 (P = 0.092) in observational studies and 5.8 mg/dL (P = 0.090) in intervention trials. Conclusions Plant-based diets are associated with decreased total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol, but not with decreased triglycerides. Systematic Review Registration PROSPERO number CRD42015023783. Available at: https://www.crd.york.ac.uk/PROSPERO/display_record.asp?ID=CRD42015023783. PMID:28938794

Scaling-up vaccine production: implementation aspects of a biomass growth observer and controller.

PubMed

Soons, Zita I T A; van den IJssel, Jan; van der Pol, Leo A; van Straten, Gerrit; van Boxtel, Anton J B

2009-04-01

This study considers two aspects of the implementation of a biomass growth observer and specific growth rate controller in scale-up from small- to pilot-scale bioreactors towards a feasible bulk production process for whole-cell vaccine against whooping cough. The first is the calculation of the oxygen uptake rate, the starting point for online monitoring and control of biomass growth, taking into account the dynamics in the gas-phase. Mixing effects and delays are caused by amongst others the headspace and tubing to the analyzer. These gas phase dynamics are modelled using knowledge of the system in order to reconstruct oxygen consumption. The second aspect is to evaluate performance of the monitoring and control system with the required modifications of the oxygen consumption calculation on pilot-scale. In pilot-scale fed-batch cultivation good monitoring and control performance is obtained enabling a doubled concentration of bulk vaccine compared to standard batch production.

Investigating Flow Experience and Scientific Practices During a Mobile Serious Educational Game

NASA Astrophysics Data System (ADS)

Bressler, Denise M.; Bodzin, Alec M.

2016-10-01

Mobile serious educational games (SEGs) show promise for promoting scientific practices and high engagement. Researchers have quantified this engagement according to flow theory. This study investigated whether a mobile SEG promotes flow experience and scientific practices with eighth-grade urban students. Students playing the game ( n = 59) were compared with students in a business-as-usual control activity ( n = 120). In both scenarios, students worked in small teams. Data measures included an open-ended instrument designed to measure scientific practices, a self-report flow survey, and classroom observations. The game players had significantly higher levels of flow and scientific practices compared to the control group. Observations revealed that game teams received less whole-class instruction and review compared to the control teams. Game teachers had primarily a guide-on-the-side role when facilitating the game, while control teachers predominantly used didactic instruction when facilitating the control activity. Implications for these findings are discussed.

Effortful control mediates relations between children's attachment security and their regard for rules of conduct

PubMed Central

Nordling, Jamie Koenig; Boldt, Lea J.; O'Bleness, Jessica; Kochanska, Grazyna

2015-01-01

Although attachment security has been associated with children's rule-compatible conduct, the mechanism through which attachment influences early regard for rules is not well established. We hypothesized that effortful control would mediate the link between security and indicators of children's emerging regard for rules (discomfort following rule violations, internalization of parents' and experimenter's rules, few externalizing behaviors). In a longitudinal study, the Attachment Q-Set was completed by parents, effortful control was observed, and Regard for Rules was observed and rated by parents. The proposed model fit the data well: Children's security to mothers predicted their effortful control, which in turn had a direct link to a greater Regard for Rules. Children's security with fathers did not predict effortful control. The mother-child relationship appears particularly important for positive developmental cascades of self-regulation and socialization. PMID:27158193

Input-output identification of controlled discrete manufacturing systems

NASA Astrophysics Data System (ADS)

Estrada-Vargas, Ana Paula; López-Mellado, Ernesto; Lesage, Jean-Jacques

2014-03-01

The automated construction of discrete event models from observations of external system's behaviour is addressed. This problem, often referred to as system identification, allows obtaining models of ill-known (or even unknown) systems. In this article, an identification method for discrete event systems (DESs) controlled by a programmable logic controller is presented. The method allows processing a large quantity of observed long sequences of input/output signals generated by the controller and yields an interpreted Petri net model describing the closed-loop behaviour of the automated DESs. The proposed technique allows the identification of actual complex systems because it is sufficiently efficient and well adapted to cope with both the technological characteristics of industrial controllers and data collection requirements. Based on polynomial-time algorithms, the method is implemented as an efficient software tool which constructs and draws the model automatically; an overview of this tool is given through a case study dealing with an automated manufacturing system.

InternationaL cross-sectIonAl and longItudinal assessment on aSthma cONtrol in European adult patients - the LIAISON study protocol

PubMed Central

2013-01-01

Background According to international guidelines, the goal of asthma management is to achieve and maintain control of the disease, which can be assessed using composite measures. Prospective studies are required to determine how these measures are associated with asthma outcomes and/or future risk. The ‘InternationaL cross-sectIonAl and longItudinal assessment on aSthma cONtrol (LIAISON)’ observational study has been designed to evaluate asthma control and its determinants, including components of asthma management. Methods/design The LIAISON study will be conducted in 12 European countries and comprises a cross-sectional phase and a 12-month prospective phase. Both phases will aim at assessing asthma control (six-item Asthma Control Questionnaire, ACQ), asthma-related quality of life (Mini Asthma Quality of Life Questionnaire, Mini-AQLQ), risk of non-adherence to treatment (four-item Morisky Medication Adherence Scale, MMAS-4), potential reasons for poor control, treatment strategies and associated healthcare costs. The cross-sectional phase will recruit > 8,000 adult patients diagnosed with asthma for at least 6 months and receiving the same asthma treatment in the 4 weeks before enrolment. The prospective phase will include all patients with uncontrolled/poorly controlled asthma at the initial visit to assess the proportion reaching control during follow-up and to examine predictors of future risk. Visits will take place after 3, 6 and 12 months. Discussion The LIAISON study will provide important information on the prevalence of asthma control and on the quality of life in a broad spectrum of real-life patient populations from different European countries and will also contribute to evaluate differences in management strategies and their impact on healthcare costs over 12 months of observation. Trial registration ClinicalTrials.gov identifier, NCT01567280. PMID:23530817

Protective effects of recombinant human brain natriuretic peptide in perioperative period during open heart surgery.

PubMed

Xu, Yunbin; Li, Yong; Bao, Weiguo; Qiu, Shi

2018-03-01

The aim of the present study was to evaluate the protective effects and safety aspects of recombinant human brain natriuretic peptide (rhBNP) on cardiac functions of patients undergoing open-heart surgery during perioperative period. In total, 150 patients undergoing open heart surgery in the Second Hospital of Shandong Universty from August 2015 to July 2016 were randomly divided into control group and observation group each with 75 cases. Patients in control group were treated by routine rehabilitation while patients in the observation group were treated by both the routine rehabilitation and rhBNP. All the observations were made before operation, after operation and 7 days after operation. The changes of N-terminal pro-brain natriuretic peptide (NT-proBNP) of patients, the left ventricular ejection fraction (LVEF), cardiac function [Cardiac output (CO), pulmonary capillary wedge pressure (PAWP) and central venous pressure (CVP)] of patients were measured. Further, respirator support time, ICU stay time, incidence of complications and vital signs (BP, HR, SaO2) of patients in the two groups were also compared. NT-proBNP levels of all patients improved after operation but it decreased in both groups after 7 days of operation. The decrease of NT-proBNP levels in observation group was significantly higher than that of control group. Whereas, LVEF, CO, PAWP and CVP of patients in both the groups increased after operation but effects were significantly higher in the observation group after 7 days of medication. Respirator support time and ICU stay time of patients in observation group were significantly shorter than those in control group, and the incidence of postoperative complications of patients in the observation group were significantly lower than the control group. Moreover, BP, HR and SaO2 of patients in observation group were significantly elevated in comparison to control group (P<0.05). Recombinant human brain natriuretic peptide (rhBNP) could significantly improve the cardiac functions of patients after open heart surgery, and is safe as well as reliable.

Cigarette smoking and risk of ovarian cancer: a pooled analysis of 21 case–control studies

PubMed Central

Faber, Mette T.; Kjær, Susanne K.; Dehlendorff, Christian; Chang-Claude, Jenny; Andersen, Klaus K.; Høgdall, Estrid; Webb, Penelope M.; Jordan, Susan J.; Rossing, Mary Anne; Doherty, Jennifer A.; Lurie, Galina; Thompson, Pamela J.; Carney, Michael E.; Goodman, Marc T.; Ness, Roberta B.; Modugnos, Francesmary; Edwards, Robert P.; Bunker, Clareann H.; Goode, Ellen L.; Fridley, Brooke L.; Vierkant, Robert A.; Larson, Melissa C.; Schildkraut, Joellen; Cramer, Daniel W.; Terry, Kathryn L.; Vitonis, Allison F.; Bandera, Elisa V.; Olson, Sara H.; King, Melony; Chandran, Urmila; Kiemeney, Lambertus A.; Massuger, Leon F. A. G.; van Altena, Anne M.; Vermeulen, Sita H.; Brinton, Louise; Wentzensen, Nicolas; Lissowska, Jolanta; Yang, Hannah P.; Moysich, Kirsten B.; Odunsi, Kunle; Kasza, Karin; Odunsi-Akanji, Oluwatosin; Song, Honglin; Pharaoh, Paul; Shah, Mitul; Whittemore, Alice S.; McGuire, Valerie; Sieh, Weiva; Sutphen, Rebecca; Menon, Usha; Gayther, Simon A.; Ramus, Susan J.; Gentry-Maharaj, Aleksandra; Pearce, Celeste Leigh; Wu, Anna H.; Pike, Malcolm C.; Risch, Harvey A.

2013-01-01

Purpose The majority of previous studies have observed an increased risk of mucinous ovarian tumors associated with cigarette smoking, but the association with other histological types is unclear. In a large pooled analysis, we examined the risk of epithelial ovarian cancer associated with multiple measures of cigarette smoking with a focus on characterizing risks according to tumor behavior and histology. Methods We used data from 21 case–control studies of ovarian cancer (19,066 controls, 11,972 invasive and 2,752 borderline cases). Study-specific odds ratios (OR) and 95 % confidence intervals (CI) were obtained from logistic regression models and combined into a pooled odds ratio using a random effects model. Results Current cigarette smoking increased the risk of invasive mucinous (OR = 1.31; 95 % CI: 1.03–1.65) and borderline mucinous ovarian tumors (OR = 1.83; 95 % CI: 1.39–2.41), while former smoking increased the risk of borderline serous ovarian tumors (OR = 1.30; 95 % CI: 1.12–1.50). For these histological types, consistent dose– response associations were observed. No convincing associations between smoking and risk of invasive serous and endometrioid ovarian cancer were observed, while our results provided some evidence of a decreased risk of invasive clear cell ovarian cancer. Conclusions Our results revealed marked differences in the risk profiles of histological types of ovarian cancer with regard to cigarette smoking, although the magnitude of the observed associations was modest. Our findings, which may reflect different etiologies of the histological types, add to the fact that ovarian cancer is a heterogeneous disease. PMID:23456270

Neural-network-observer-based optimal control for unknown nonlinear systems using adaptive dynamic programming

NASA Astrophysics Data System (ADS)

Liu, Derong; Huang, Yuzhu; Wang, Ding; Wei, Qinglai

2013-09-01

In this paper, an observer-based optimal control scheme is developed for unknown nonlinear systems using adaptive dynamic programming (ADP) algorithm. First, a neural-network (NN) observer is designed to estimate system states. Then, based on the observed states, a neuro-controller is constructed via ADP method to obtain the optimal control. In this design, two NN structures are used: a three-layer NN is used to construct the observer which can be applied to systems with higher degrees of nonlinearity and without a priori knowledge of system dynamics, and a critic NN is employed to approximate the value function. The optimal control law is computed using the critic NN and the observer NN. Uniform ultimate boundedness of the closed-loop system is guaranteed. The actor, critic, and observer structures are all implemented in real-time, continuously and simultaneously. Finally, simulation results are presented to demonstrate the effectiveness of the proposed control scheme.

Persistent hyperphagia in acquired brain injury; an observational case study of patients receiving inpatient rehabilitation.

PubMed

Rowell, Arleen M; Faruqui, Rafey A

2010-01-01

Morbid hunger or persistent hyperphagia is a relatively rare but potentially life threatening complication of acquired brain injury (ABI). This paper presents findings from an observational case study of patients with hyperphagia receiving inpatient neurobehavioural rehabilitation following their acquired brain injury. The case study has utilized dietetic and medical records of identified patients to confirm the persistent and serious nature of this presentation in order to extract important management principles. The findings confirmed that hyperphagia or morbid hunger posed potentially life-threatening health risks to the patient, primarily around weight control and fluid balance, and risks of aggression towards professional and family carers. Pharmacological or behaviour modification interventions were only partially successful in management of this presentation. The study identified a high need for environmental and cue exposure control in management of this condition.

Neonatal Early Warning Tools for recognising and responding to clinical deterioration in neonates cared for in the maternity setting: A retrospective case-control study.

PubMed

Paliwoda, Michelle; New, Karen; Bogossian, Fiona

2016-09-01

All newborns are at risk of deterioration as a result of failing to make the transition to extra uterine life. Signs of deterioration can be subtle and easily missed. It has been postulated that the use of an Early Warning Tool may assist clinicians in recognising and responding to signs of deterioration earlier in neonates, thereby preventing a serious adverse event. To examine whether observations from a Standard Observation Tool, applied to three neonatal Early Warning Tools, would hypothetically trigger an escalation of care more frequently than actual escalation of care using the Standard Observation Tool. A retrospective case-control study. A maternity unit in a tertiary public hospital in Australia. Neonates born in 2013 of greater than or equal to 34(+0) weeks gestation, admitted directly to the maternity ward from their birthing location and whose subsequent deterioration required admission to the neonatal unit, were identified as cases from databases of the study hospital. Each case was matched with three controls, inborn during the same period and who did not experience deterioration and neonatal unit admission. Clinical and physiological data recorded on a Standard Observation Tool, from time of admission to the maternity ward, for cases and controls were charted onto each of three Early Warning Tools. The primary outcome was whether the tool 'triggered an escalation of care'. Descriptive statistics (n, %, Mean and SD) were employed. Cases (n=26) comprised late preterm, early term and post-term neonates and matched by gestational age group with 3 controls (n=78). Overall, the Standard Observation Tool triggered an escalation of care for 92.3% of cases compared to the Early Warning Tools; New South Wales Health 80.8%, United Kingdom Newborn Early Warning Chart 57.7% and The Australian Capital Territory Neonatal Early Warning Score 11.5%. Subgroup analysis by gestational age found differences between the tools in hypothetically triggering an escalation of care. The Standard Observation Tool triggered an escalation of care more frequently than the Early Warning Tools, which may be as a result of behavioural data captured on the Standard Observation Tool and escalated, which could not be on the Early Warning Tools. Findings demonstrate that a single tool applied to all gestational age ranges may not be effective in identifying early deterioration or may over trigger an escalation of care. Further research is required into the sensitivity and specificity of Early Warning Tools in neonatal sub-populations. Copyright © 2016 Elsevier Ltd. All rights reserved.

Estuarine intertidal habitat use by birds in a Pacific Northwest coastal estuary

EPA Science Inventory

Results of a year long study of the distribution of birds across five intertidal estuarine habitats reveal that tide level largely controls use of the habitats by birds. A total census of all birds observed from shoreline observation locations was made at five tide levels over s...

Development of a Rubric for Collegiate Jazz Improvisation Performance Assessment

ERIC Educational Resources Information Center

Moore, Kendall Ryan

2016-01-01

The purpose of this study was to develop a jazz improvisation rubric for the evaluation of collegiate jazz improvisation. To create this measure, research objectives were devised to investigate the aurally-observed performer-controlled components of improvisation, which aurally-observed components should be evaluated in an improvisatory…

Within-Cluster and Across-Cluster Matching with Observational Multilevel Data

ERIC Educational Resources Information Center

Kim, Jee-Seon; Steiner, Peter M.; Hall, Courtney; Thoemmes, Felix

2013-01-01

When randomized experiments cannot be conducted in practice, propensity score (PS) techniques for matching treated and control units are frequently used for estimating causal treatment effects from observational data. Despite the popularity of PS techniques, they are not yet well studied for matching multilevel data where selection into treatment…

Heart rate variability in sleep-related migraine without aura.

PubMed

Vollono, Catello; Gnoni, Valentina; Testani, Elisa; Dittoni, Serena; Losurdo, Anna; Colicchio, Salvatore; Di Blasi, Chiara; Mazza, Salvatore; Farina, Benedetto; Della Marca, Giacomo

2013-07-15

This is an observational study aimed to investigate the activity of autonomic nervous system during sleep in patients with sleep-related migraine. Eight consecutive migraineurs without aura were enrolled (6 women and 2 men), aged 30 to 62 years (mean 48.1 ± 9.3 years). Inclusion criteria were: high frequency of attacks (> 5 per month) and occurrence of more than 75% of the attacks during sleep causing an awakening. Patients were compared with a control group of 55 healthy subjects (23 men and 32 women, mean age 54.2 ± 13.0 years), and with a further control group of 8 age- and gender-matched healthy controls. Patient and controls underwent polysomnography and heart rate variability analysis. A significant reduction of the LF/HF ratio during N2 and N3 sleep stages was observed in migraineurs compared with controls. No differences in sleep macrostructure were observed; cyclic alternating pattern (CAP) time and CAP rate were lower in migraineurs than in controls. These findings indicate a peculiar modification of the autonomic balance during sleep in sleep-related migraine. The reduction of LF/HF ratio in NREM sleep was observed in controls, but it was quantitatively much more evident in migraineurs. Changes in LF/HF could be consequent to an autonomic unbalance which could manifest selectively (or alternatively become more evident) during sleep. These findings, together with the reduction in CAP rate, could be an expression of reduced arousability during sleep in patients with sleep-related migraine. The simultaneous involvement of the autonomic, arousal, and pain systems might suggest involvement of the hypothalamic pathways.

Factors Associated with Tuberculosis Treatment Default in an Endemic Area of the Brazilian Amazon: A Case Control-Study

PubMed Central

Garrido, Marlucia da Silva; Penna, Maria Lucia; Perez-Porcuna, Tomàs M.; de Souza, Alexandra Brito; Marreiro, Leni da Silva; Albuquerque, Bernardino Claudio; Martínez-Espinosa, Flor Ernestina; Bührer-Sékula, Samira

2012-01-01

Setting Treatment default is a serious problem in tuberculosis control because it implies persistence of infection source, increased mortality, increased relapse rates and facilitates the development of resistant strains. Objective This study analyzed tuberculosis treatment default determinants in the Amazonas State to contribute in planning appropriate control interventions. Design Observational study with a retrospective cohort using Brazilian Disease Notification System data from 2005 to 2010. A nested case control study design was used. Patients defaulting from treatment were considered as ‘cases’ and those completing treatment as ‘controls’. In the analysis, 11,312 tuberculosis patients were included, 1,584 cases and 9,728 controls. Results Treatment default was observed to be associated to previous default (aOR 3.20; p<0.001), HIV positivity (aOR 1.62; p<0.001), alcoholism (aOR 1.51; p<0.001), low education level (aOR 1.35; p<0.001) and other co-morbidities (aOR 1.31; p = 0.05). Older patients (aOR 0.98; p = 0.001) and DOT (aOR 0,72; p<0.01) were considered as protective factor for default. Conclusions Associated factors should be considered in addressing care and policy actions to tuberculosis control. Information on disease and treatment should be intensified and appropriate to the level of education of the population, in order to promote adherence to treatment and counter the spread of multidrug resistance to anti-TB drugs. PMID:22720052

Processing verbal morphology in patients with congenital left-hemispheric brain lesions.

PubMed

Knecht, Marion; Lidzba, Karen

2016-01-01

The goal of this study was to test whether children, teenagers and adults with congenital left-hemispheric brain lesions master the regularities of German verbal inflectional morphology. Thirteen patients and 35 controls without brain damage participated in three experiments. A grammaticality judgment task, a participle inflection task and a nonce-verb inflection task revealed significant differences between patients and controls. In addition, a main effect of verb type could be observed as patients and controls made more mistakes with irregular than with regular verbs. The findings indicate that the congenitally damaged brain not only has difficulties with complex syntactic structures during language development, as reported by earlier studies, but also has persistent deficits on the morphological level. These observations suggest that the plasticity of the developing brain cannot fully compensate for congenital brain damage which affects regions associated with language functions. Copyright © 2016 Elsevier Inc. All rights reserved.

Distribution of Blood Pressure Data from People Living Near AN Airport

NASA Astrophysics Data System (ADS)

GOTO, K.; KANEKO, T.

2002-02-01

We observed blood pressure in general health examination data around a city airport and compared the data with those from a calm suburban area of the city. Information was also collected on the short-term history of medication and lifestyle including smoking, drinking and eating salty foods. This cross-sectional study on 469 women showed that systolic and diastolic blood pressure was not associated with aircraft noise levels in the area, even after controlling for variables regarding anti-hypertension treatment and lifestyle factors. A comparative study on 469 women from an area around an airport and 1177 women from a suburban control area showed no significant differences between blood pressure and other medical tests controlling for the variables of medication and lifestyle. Changes in blood pressure after 8 years were observed in 183 women around the airport. No significant differences among three zones with different levels of aircraft noise were found.

Space Suit Thermal Dynamics

NASA Technical Reports Server (NTRS)

Campbell, Anthony B.; Nair, Satish S.; Miles, John B.; Iovine, John V.; Lin, Chin H.

1998-01-01

The present NASA space suit (the Shuttle EMU) is a self-contained environmental control system, providing life support, environmental protection, earth-like mobility, and communications. This study considers the thermal dynamics of the space suit as they relate to astronaut thermal comfort control. A detailed dynamic lumped capacitance thermal model of the present space suit is used to analyze the thermal dynamics of the suit with observations verified using experimental and flight data. Prior to using the model to define performance characteristics and limitations for the space suit, the model is first evaluated and improved. This evaluation includes determining the effect of various model parameters on model performance and quantifying various temperature prediction errors in terms of heat transfer and heat storage. The observations from this study are being utilized in two future design efforts, automatic thermal comfort control design for the present space suit and design of future space suit systems for Space Station, Lunar, and Martian missions.

Controlling the intermediate structure of an ionic liquid for f-block element separations

DOE PAGES

Abney, Carter W.; Do, Changwoo; Luo, Huimin; ...

2017-04-19

Recent research has revealed molecular structure beyond the inner coordination sphere is essential in defining the performance of separations processes, but nevertheless remains largely unexplored. Here we apply small angle neutron scattering (SANS) and x-ray absorption fine structure (XAFS) spectroscopy to investigate the structure of an ionic liquid system studied for f-block element separations. SANS data reveal dramatic changes in the ionic liquid microstructure (~150 Å) which we demonstrate can be controlled by judicious selection of counter ion. Mesoscale structural features (> 500 Å) are also observed as a function of metal concentration. XAFS analysis supports formation of extended aggregatemore » structures, similar to those observed in traditional solvent extraction processes, and suggest additional parallels may be drawn from further study. As a result, achieving precise tunability over the intermediate features is an important development in controlling mesoscale structure and realizing advanced new forms of soft matter.« less

Influence of one-year neurologic outcome of treatment on newborns with moderate and severe hypoxic-ischemic encephalopathy by rhuEP0 combined with ganglioside (GM1).

PubMed

Zhu, X-Y; Ye, M-Y; Zhang, A-M; Wang, W-D; Zeng, F; Li, J-L; Fang, F

2015-10-01

To observe the one-year neurologic prognostic outcome of newborns with moderate and severe hypoxic-ischemic encephalopathy (HIE) who received recombinant human erythropoietin (rhuEPO) combined with exogenous monosialotetrahexosylganglioside (GM1) treatment to provide new guidelines for clinical treatment. Seventy-six newborns with moderate and severe HIE were selected from February 2011 to February 2014 in our hospital. This study received the informed consent of our hospital's Ethics Committee and the newborns' guardians. The newborns were divided to an observation group (n = 34 cases) and a control group (n = 42 cases). All newborns underwent hypothermia and conventional treatment for their conditions. The control group received GMl treatment and observation group received rhuEPO combined with GMl treatment. The curative differences and neural behavior from these two groups were compared. The excellent, efficient proportion and total effective rate of the newborns from the observation group were higher than the control group. The death rate, cerebral palsy and the invalid ratio of the newborns from the observation group were lower than that of the control group. Awareness, muscle tension, primitive reflex and increased intracranial pressure recovery time of the newborns in the observation group were less than those of the control group. The Neonatal Behavior Neurological Assessment (NBNA) score of both groups after the treatment of 7, 14 and 28 days were significantly higher and increased with time (p < 0.05). The MDI, PDI and DQ score of newborns from the two groups all increased after treatment of 3, 6 and 12 months than those of before, which increased with time (p < 0.05). The rhuEPO + GMl treatment in newborns with HIE improves short-term clinical effects and long-term neurological symptoms.

Interpreting febrile neutropenia rates from randomized, controlled trials for consideration of primary prophylaxis in the real world: a systematic review and meta-analysis.

PubMed

Truong, J; Lee, E K; Trudeau, M E; Chan, K K W

2016-04-01

Guidelines recommend primary prophylaxis (PP) with granulocyte-colony-stimulating factors (G-CSF) for patients above a febrile neutropenia (FN) risk threshold of 20%. Practitioners often use FN rates of regimens based on data from randomized, controlled trials (RCTs), which are often comprised of highly selected patients. Patients in the community setting may be at higher risk of FN. A systematic literature search was conducted for full-length articles reporting FN rates for breast cancer-related chemotherapies between January 1996 and February 2014. A regimen was included if there was at least one RCT and one observational study. Meta-regression was used to model the odds of FN. 130 studies involving 29 regimens and 50 069 patients were identified. Sixty-five observational study (n = 7812) and 110 RCT (n = 42 257) cohorts were included. The unadjusted FN rate was 11.7% in observational and 7.9% in RCT cohorts. The univariable odds ratio (OR) for FN in the observational study compared with RCT cohorts was 1.58 [95% confidence interval (CI) 1.09-2.28; P = 0.017]. The FN rates remained significantly higher in the observational study compared with RCT cohorts (OR = 1.74; 95% CI 1.15-2.62; P = 0.012) after adjusting for age, chemotherapy intent, and regimen; this meant that a 13% (95% CI 8.7% to 17.9%) FN rate in RCT would translate into 20% FN rate in observational study. FN rates in the observational studies are significantly higher than suggested by RCTs. Guidelines should clarify how FN rates from RCTs should be applied in clinical practice. Large population-based studies are needed to confirm FN rates in the real world. © The Author 2015. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

The treatment of adolescent idiopathic scoliosis (AIS) according to present evidence. A systematic review.

PubMed

Weiss, H-R; Goodall, D

2008-06-01

Traditionally, the treatment options for adolescent idiopathic scoliosis (AIS), the most common form of scoliosis, are exercises; in-patient rehabilitation; braces and surgery. The outcomes of treatments are usually compared with the natural history or observation (non-intervention). The aim of this paper was to provide a synopsis of all treatment options in the light of evidence based practice (EBP). A systematic review was carried out using the most encompassing databases available. Literature has been searched for the outcome parameter ''rate of progression'' and only prospective controlled studies that have considered the treatment versus the natural history have been included. The search strategy included the following terms: ''adolescent idiopathic scoliosis''; ''idiopathic scoliosis''; ''natural history''; ''observation''; ''physiotherapy''; ''physical therapy''; ''rehabilitation''; ''bracing''; ''orthotics'' and ''surgery''. Prospective short-term studies have been found to support outpatient physiotherapy. One prospective controlled study was found to support scoliosis in-patient rehabilitation (SIR). One prospective multi-centre study, a long-term prospective controlled study and a meta-analysis have been found to support bracing. No controlled study, neither short, mid nor long-term, was found to reveal any substantial evidence to support surgery as a treatment for this condition. There is some evidence supporting the conservative treatment for AIS. No substantial evidence has been found in terms of prospective controlled studies to support surgical intervention. In light of the unknown long-term effects of surgery, a randomised controlled trial (RCT) seems necessary. Due to the presence of evidence to support conservative treatments, a plan to compose a RCT for conservative treatment options seems unethical. But it is also important to conclude that the evidence for conservative treatments is weak in number and length.

Observer enhanced control for spin-stabilized tethered formation in earth orbit

NASA Astrophysics Data System (ADS)

Guang, Zhai; Yuyang, Li; Liang, Bin

2018-04-01

This paper addresses the issues relevant to control of spin-stabilized tethered formation in circular orbit. Due to the dynamic complexities and nonlinear perturbations, it is challenging to promote the control precision for the formation deployment and maintenance. In this work, the formation dynamics are derived with considering the spinning rate of the central body, then major attention is dedicated to develop the nonlinear disturbance observer. To achieve better control performance, the observer-enhanced controller is designed by incorporating the disturbance observer into the control loop, benefits from the disturbance compensation are demonstrated, and also, the dependences of the disturbance observer performance on some important parameters are theoretically and numerically analyzed.

Study on the clinical value of alprostadil combined with α-lipoic acid in treatment of type 2 diabetes mellitus patients with erectile dysfunction.

PubMed

Zhang, L; Zhang, H-Y; Huang, F-C; Huang, Q; Liu, C; Li, J-R

2016-09-01

We investigated the clinical value of alprostadil combined with the α-lipoic acid in treating type 2 diabetes mellitus with erectile dysfunction (DMED). We selected a total of 76 cases of patients who were admitted to endocrinology department of our hospital from June 2014 to June 2015 and diagnosed as DMED, and the average age was (46.7 ± 7.2) years old, average course of diabetes mellitus was (6.2 ± 2.8) years and average body mass index was (25.4 ± 1.3) kg/m2. 40 cases were randomly divided in the observation group while 36 cases were divided in the control group. They received blood glucose control therapy. The patients in the observation group received 60 mg alprostadil hydrochloride and 600 mg α-lipoic acid added into 250 mL normal saline, intravenous drip once per day for 2 weeks. The patients in the control group took tadalafil 5 mg orally, once per night for 2 weeks as a course of treatment. There were no cases of loss. The effective rate of treatment in observation group is significantly higher than that in the control group (95.0% vs. 80.5%, p < 0.05). The score of IIEF-5, EHGS and the FMD value of brachial artery of the observation group after the operation were significantly higher than that of the control group (p < 0.05). The adverse reaction rate in the observation group was lower than that in the control group (7.5% vs. 13.9%, p < 0.05). Alprostadil combined with α-lipoic acid can improve DMED patients' vascular endothelial function and erection hardness to treat erectile dysfunction with less adverse effects and better safety.

A micro-fluidic treadmill for observing suspended plankton in the lab

NASA Astrophysics Data System (ADS)

Jaffe, J. S.; Laxton, B.; Garwood, J. C.; Franks, P. J. S.; Roberts, P. L.

2016-02-01

A significant obstacle to laboratory studies of interactions between small organisms ( mm) and their fluid environment is our ability to obtain high-resolution images while allowing freedom of motion. This is because as the organisms sink, they will often move out of the field of view of the observation system. One solution to this problem is to impose a water circulation pattern that preserves their location relative to the camera system while imaging the organisms away from the glass walls. To accomplish this we have designed and created a plankton treadmill. Our computer-controlled system consists of a digital video camera attached to a macro or microscope and a micro-fluidic pump whose flow is regulated to maintain a suspended organism's position relative to the field of view. Organisms are detected and tracked in real time in the video frames, allowing a control algorithm to compensate for any vertical movement by adjusting the flow. The flow control can be manually adjusted using on-screen controls, semi-automatically adjusted to allow the user to select a particular organism to be tracked or fully automatic through the use of classification and tracking algorithms. Experiments with a simple cm-sized cuvette and a number of organisms that are both positively and negatively buoyant have demonstrated the success of the system in permitting longer observation times than would be possible in the absence of a controlled-flow environment. The subjects were observed using a new dual-view, holographic imaging system that provides 3-dimensional microscopic observations with relatively isotropic resolution. We will present the system design, construction, the control algorithm, and some images obtained with the holographic system, demonstrating its effectiveness. Small particles seeded into the flow clearly show the 3D flow fields around the subjects as they freely sink or swim.

A naturalistic study of railway controllers.

PubMed

Farrington-Darby, T; Wilson, John R; Norris, B J; Clarke, Theresa

There is an increasing prevalence for work to be analysed through naturalistic study, especially using ethnographically derived methods of enquiry and qualitative field research. The relatively unexplored domain of railway control (in comparison to signalling) in the UK is described in terms of features derived from observations and semi-structured interviews. In addition, task diagrams (a technique taken from the Applied Cognitive Task Analysis toolkit) are used to represent controllers' core elements of work, i.e. to manage events or incidents, and to identify the challenging steps in the process. The work features identified, the task diagrams, and the steps identified as challenging form a basis from which future ergonomics studies on railway controllers in the UK will be carried out.

The effects of testosterone on body composition in obese men are not sustained after cessation of testosterone treatment.

PubMed

Ng Tang Fui, Mark; Hoermann, Rudolf; Zajac, Jeffrey D; Grossmann, Mathis

2017-10-01

Testosterone treatment in obese dieting men augments the diet-associated loss of fat mass, but protects against loss of lean mass. We assessed whether body composition changes are maintained following withdrawal of testosterone treatment. We conducted a prespecified double-blind randomized placebo-controlled observational follow-up study of a randomized controlled trial (RCT). Participants were men with baseline obesity (body mass index >30 kg/m 2 ) and a repeated total testosterone level <12 nmol/L, previously enrolled in a 56-week testosterone treatment trial combined with a weight loss programme. Main outcome measures were mean adjusted differences (MAD) (95% confidence interval), in body composition between testosterone- and placebo-treated men at the end of the observation period. Of the 100 randomized men, 82 completed the RCT and 64 the subsequent observational study. Median [IQR] observation time after completion of the RCT was 82 weeks [74; 90] in men previously receiving testosterone (cases) and 81 weeks [67;91] in men previously receiving placebo (controls), P=.51. At the end of the RCT, while losing similar amounts of weight, cases had, compared to controls, lost more fat mass, MAD -2.9 kg (-5.7, -0.2), P=.04, but had lost less lean mass MAD 3.4 kg (1.3, 5.5), P=.002. At the end of the observation period, the former between-group differences in fat mass, MAD -0.8 kg (-3.6, 2.0), P=1.0, in lean mass, MAD -1.3 kg (-3.0, 0.5), P=.39, and in appendicular lean mass, MAD -0.1 kg/m 2 (-0.3, 0.1), P=.45, were no longer apparent. During observation, cases lost more lean mass, MAD -3.7 kg (-5.5, -1.9), P=.0005, and appendicular lean mass, MAD -0.5 kg/m 2 (-0.8, -0.3), P<.0001 compared to controls. The favourable effects of testosterone on body composition in men subjected to a concomitant weight loss programme were not maintained at 82 weeks after testosterone treatment cessation. © 2017 John Wiley & Sons Ltd.

Testing Alternative Explanations for the Associations Between Parenting and Adolescent Suicidal Problems

PubMed Central

Boeninger, Daria K.; Masyn, Katherine E.; Conger, Rand D.

2012-01-01

Although studies have established associations between parenting characteristics and adolescent suicidality, the strength of the evidence for these links remains unclear, largely because of methodological limitations, including lack of accounting for possible child effects on parenting. This study addresses these issues by using autoregressive cross-lag models with data on 802 adolescents and their parents across 5 years. Observed parenting behaviors predicted change in adolescent suicidal problems across one-year intervals even after controlling for adolescents’ effects on parenting. Nurturant-involved parenting continued to demonstrate salutary effects after controlling for adolescent and parent internalizing psychopathology: over time, observed nurturant-involved parenting reduced the likelihood of adolescent suicidal problems. This study increases the empirical support implicating parenting behaviors in the developmental course of adolescent suicidality. PMID:24244079

A Two-Year Longitudinal MRI Study of the Corpus Callosum in Autism

PubMed Central

Frazier, Thomas W.; Keshavan, Matcheri S.; Minshew, Nancy J.; Hardan, Antonio Y.

2015-01-01

A growing body of literature has identified size reductions of the corpus callosum (CC) in autism. However, to our knowledge, no published studies have reported on the growth of CC volumes in youth with autism. Volumes of the total CC and its sub-divisions were obtained from 23 male children with autism and 23 age-matched male controls at baseline and 2-year follow-up. Persistent reductions in total CC volume were observed in participants with autism relative to controls. Only the rostral body sub-division showed a normalization of size over time. Persistent reductions are consistent with the diagnostic stability and life-long impairment observed in many individuals with autism. Multimodal imaging studies are needed to identify specific fiber tracks contributing to CC reductions. PMID:22350341

[Clinical evaluation of influence of aspirin on post-operative bleeding after tooth extraction in the elderly].

PubMed

Wang, Wen-ying; Cui, Nian-hui; Wang, En-bo; Zhang, Wei

2013-05-01

To investigate the feasibility of continuation of aspirin before tooth extraction in the elderly. The patients enrolled in this study were the elderly requiring a single non-impacted tooth extraction. 300 elderly outpatients used lidocaine local infiltration anesthesia, 200 patients without using aspirin before tooth extraction served as control group I, 100 patients with prolong use of aspirin before tooth extraction as observation group I. 300 elderly outpatients used compound articaine local infiltration anesthesia, 200 patients without using aspirin before tooth extraction served as control group II, 100 patients with prolong use of aspirin before tooth extraction as observation group II.Bleedings at 5, 10, 30 min, 24 h after tooth extraction were observed and the relationship between postoperative bleeding and intake of aspirin was analyzed. There was no significant difference at 5, 10, 30 min, 24 h in postoperative bleeding after extraction between control group I and observation group. The incidence of bleeding of observation group II after tooth extraction at 5 min was higher than that of control group II and there was no significant difference at 10, 30 min, 24 h between the two groups. Continuation of aspirin have no influence on postoperative bleeding. Therefore we suggest that there was no indication to discontinue aspirin for the elderly before a single non-impacted tooth extraction.

Evaluation of the effect of Spiritual care on patients with generalized anxiety and depression: a randomized controlled study.

PubMed

Sankhe, A; Dalal, K; Save, D; Sarve, P

2017-12-01

The present study was conducted to assess the effect of spiritual care in patients with depression, anxiety or both in a randomized controlled design. The participants were randomized either to receive spiritual care or not and Hamilton anxiety rating scale-A (HAM-A), Hamilton depression rating scale-D (HAM-D), WHO-quality of life-Brief (WHOQOL-BREF) and Functional assessment of chronic illness therapy - Spiritual well-being (FACIT-Sp) were assessed before therapy and two follow-ups at 3 and 6 week. However, with regard to the spiritual care therapy group, statistically significant differences were observed in both HAM-A and HAM-D scales between the baseline and visit 2 (p < 0.001), thus significantly reducing symptoms of anxiety and depression, respectively. No statistically significant differences were observed for any of the scales during the follow-up periods for the control group of participants. When the scores were compared between the study groups, HAM-A, HAM-D and FACIT-Sp 12 scores were significantly lower in the interventional group as compared to the control group at both third and sixth weeks. This suggests a significant improvement in symptoms of anxiety and depression in the spiritual care therapy group than the control group; however, large randomized controlled trials with robust design are needed to confirm the same.

Conflicting results between randomized trials and observational studies on the impact of proton pump inhibitors on cardiovascular events when coadministered with dual antiplatelet therapy: systematic review.

PubMed

Melloni, Chiara; Washam, Jeffrey B; Jones, W Schuyler; Halim, Sharif A; Hasselblad, Victor; Mayer, Stephanie B; Heidenfelder, Brooke L; Dolor, Rowena J

2015-01-01

Discordant results have been reported on the effects of concomitant use of proton pump inhibitors (PPIs) and dual antiplatelet therapy (DAPT) for cardiovascular outcomes. We conducted a systematic review comparing the effectiveness and safety of concomitant use of PPIs and DAPT in the postdischarge treatment of unstable angina/non-ST-segment-elevation myocardial infarction patients. We searched for clinical studies in MEDLINE, EMBASE, and the Cochrane Database of Systematic Reviews, from 1995 to 2012. Reviewers screened and extracted data, assessed applicability and quality, and graded the strength of evidence. We performed meta-analyses of direct comparisons when outcomes and follow-up periods were comparable. Thirty-five studies were eligible. Five (4 randomized controlled trials and 1 observational) assessed the effect of omeprazole when added to DAPT; the other 30 (observational) assessed the effect of PPIs as a class when compared with no PPIs. Random-effects meta-analyses of the studies assessing PPIs as a class consistently reported higher event rates in patients receiving PPIs for various clinical outcomes at 1 year (composite ischemic end points, all-cause mortality, nonfatal MI, stroke, revascularization, and stent thrombosis). However, the results from randomized controlled trials evaluating omeprazole compared with placebo showed no difference in ischemic outcomes, despite a reduction in upper gastrointestinal bleeding with omeprazole. Large, well-conducted observational studies of PPIs and randomized controlled trials of omeprazole seem to provide conflicting results for the effect of PPIs on cardiovascular outcomes when coadministered with DAPT. Prospective trials that directly compare pharmacodynamic parameters and clinical events among specific PPI agents in patients with unstable angina/non-ST-segment-elevation myocardial infarction treated with DAPT are warranted. © 2015 American Heart Association, Inc.

Propensity score models in observational comparative effectiveness studies: cornerstone of design or statistical afterthought?

PubMed

Robinson, John W

2012-03-01

Propensity score models are increasingly used in observational comparative effectiveness studies to reduce confounding by covariates that are associated with both a study outcome and treatment choice. Any such potentially confounding covariate will bias estimation of the effect of treatment on the outcome, unless the distribution of that covariate is well-balanced between treatment and control groups. Constructing a subsample of treated and control subjects who are matched on estimated propensity scores is a means of achieving such balance for covariates that are included in the propensity score model. If, during study design, investigators assemble a comprehensive inventory of known and suspected potentially confounding covariates, examination of how well this inventory is covered by the chosen dataset yields an assessment of the extent of bias reduction that is possible by matching on estimated propensity scores. These considerations are explored by examining the designs of three recently published comparative effectiveness studies.

Methodology Series Module 2: Case-control Studies.

PubMed

Setia, Maninder Singh

2016-01-01

Case-Control study design is a type of observational study. In this design, participants are selected for the study based on their outcome status. Thus, some participants have the outcome of interest (referred to as cases), whereas others do not have the outcome of interest (referred to as controls). The investigator then assesses the exposure in both these groups. The investigator should define the cases as specifically as possible. Sometimes, definition of a disease may be based on multiple criteria; thus, all these points should be explicitly stated in case definition. An important aspect of selecting a control is that they should be from the same 'study base' as that of the cases. We can select controls from a variety of groups. Some of them are: General population; relatives or friends; and hospital patients. Matching is often used in case-control control studies to ensure that the cases and controls are similar in certain characteristics, and it is a useful technique to increase the efficiency of the study. Case-Control studies can usually be conducted relatively faster and are inexpensive - particularly when compared with cohort studies (prospective). It is useful to study rare outcomes and outcomes with long latent periods. This design is not very useful to study rare exposures. Furthermore, they may also be prone to certain biases - selection bias and recall bias.

A Novel Multi-Phosphonate Surface Treatment of Titanium Dental Implants: A Study in Sheep

PubMed Central

von Salis-Soglio, Marcella; Stübinger, Stefan; Sidler, Michéle; Klein, Karina; Ferguson, Stephen J.; Kämpf, Käthi; Zlinszky, Katalin; Buchini, Sabrina; Curno, Richard; Péchy, Péter; Aronsson, Bjorn-Owe; von Rechenberg, Brigitte

2014-01-01

The aim of the present study was to evaluate a new multi-phosphonate surface treatment (SurfLink®) in an unloaded sheep model. Treated implants were compared to control implants in terms of bone to implant contact (BIC), bone formation, and biomechanical stability. The study used two types of implants (rough or machined surface finish) each with either the multi-phosphonate Wet or Dry treatment or no treatment (control) for a total of six groups. Animals were sacrificed after 2, 8, and 52 weeks. No adverse events were observed at any time point. At two weeks, removal torque showed significantly higher values for the multi-phosphonate treated rough surface (+32% and +29%, Dry and Wet, respectively) compared to rough control. At 52 weeks, a significantly higher removal torque was observed for the multi-phosphonate treated machined surfaces (+37% and 23%, Dry and Wet, respectively). The multi-phosphonate treated groups showed a positive tendency for higher BIC with time and increased new-old bone ratio at eight weeks. SEM images revealed greater amounts of organic materials on the multi-phosphonate treated compared to control implants, with the bone fracture (from the torque test) appearing within the bone rather than at the bone to implant interface as it occurred for control implants. PMID:25215424

Parent-child mealtime interactions in racially/ethnically diverse families with preschool-age children.

PubMed

Kong, Angela; Jones, Blake L; Fiese, Barbara H; Schiffer, Linda A; Odoms-Young, Angela; Kim, Yoonsang; Bailey, Lauren; Fitzgibbon, Marian L

2013-12-01

Family meals may improve diet and weight outcomes in children; however, results from nationally representative samples suggest that these relationships vary by race/ethnicity. Observing parent-child mealtime interactions may lend insight to why racial/ethnic differences exist. In this pilot study, a multi-ethnic sample of low-income families (n = 30) with a preschool-age child was videotaped during a dinner in their home. A global coding scheme was used to assess the following: 'Action' (behaviors that divert attention from eating), 'Behavior Control' (behaviors intended to modify another person's behavior), and 'Communication' (i.e., meal-oriented, interpersonal, and critical). All families spent a significant amount of time in 'action' oriented behaviors that diverted their attention from eating. We also observed racial/ethnic differences in communication (i.e. critical) and behavior patterns (i.e. behavior control). This study demonstrated that this approach for observing parent-child mealtime interactions in a naturalistic setting among a diverse study sample was feasible; however, future studies should address how these patterns relate to dietary intake and weight status. © 2013.

Parent-child mealtime interactions in racially/ethnically diverse families with preschool-age children

PubMed Central

Kong, Angela; Jones, Blake L.; Fiese, Barbara H.; Schiffer, Linda A.; Odoms-Young, Angela; Kim, Yoonsang; Bailey, Lauren; Fitzgibbon, Marian L.

2013-01-01

Family meals may improve diet and weight outcomes in children; however, results from nationally representative samples suggest these relationships vary by race/ethnicity. Observing parent-child mealtime interactions may lend insight to why racial/ethnic differences exist. In this pilot study, a multi-ethnic sample of low-income families (n=30) with a preschool-age child were videotaped during a dinner in their home. A global coding scheme was used to assess the following: `Action' (behaviors that divert attention from eating), `Behavior Control' (behaviors intended to modify another person's behavior), and `Communication' (i.e., meal-oriented, interpersonal, and critical). All families spent a significant amount of time in `action' oriented behaviors that diverted their attention from eating. We also observed racial/ethnic differences in communication (i.e. critical) and behavior patterns (i.e. behavior control). This study demonstrated that this approach for observing parent-child mealtime interactions in a naturalistic setting among a diverse study sample was feasible; however, future studies should address how these patterns relate to dietary intake and weight status. PMID:24183134

Improved Clinical Efficacy with Wound Support Network Between Hospital and Home Care Service.

PubMed

Bergersen, Tone Kristin; Storheim, Elisabeth; Gundersen, Stina; Kleven, Linn; Johnson, Maria; Sandvik, Leiv; Kvaerner, Kari Jorunn; Ørjasæter, Nils-Otto

2016-11-01

The aim of this study was to test the efficacy of a wound support network model between the primary home care service and the hospital. The impact on wound healing rate, cost benefit, and transfer of knowledge was investigated. The intervention group was exposed to a wound support network (n = 32), and the control group continued standard organization of treatment (n = 21). Nonrandomized controlled study; observations were made before (baseline) and after the implementation of the intervention (12 weeks). Patients with chronic wounds (lasting >6 weeks and with wound area >1 cm) in Oslo, Norway. Closure of the observation wound; wound size; total number of wounds; presence of eczema, edema, and pain; number of dressings per week; time spent per dressing; and number of control appointments at the hospital. The economic impact is calculated for the hospital and for the community of Oslo, Norway. The number of control appointments (t = 3.80, P < .001) was significantly decreased, and the number of completed treatments (P = .02) was significantly increased after 12 weeks in the intervention group compared with the control group. A significant improvement was evident in the intervention group in terms of eczema (P = .02), edema (P = .03), and closing of the observational wound (46.7% cases in the intervention group versus 25.0% in the control group). A wound support network between the primary home care service and the hospital is cost-effective, improves clinical efficacy of the home care services' work, and reduces the need for consultations at the hospital.

Observational research rigour alone does not justify causal inference.

PubMed

Ejima, Keisuke; Li, Peng; Smith, Daniel L; Nagy, Tim R; Kadish, Inga; van Groen, Thomas; Dawson, John A; Yang, Yongbin; Patki, Amit; Allison, David B

2016-12-01

Differing opinions exist on whether associations obtained in observational studies can be reliable indicators of a causal effect if the observational study is sufficiently well controlled and executed. To test this, we conducted two animal observational studies that were rigorously controlled and executed beyond what is achieved in studies of humans. In study 1, we randomized 332 genetically identical C57BL/6J mice into three diet groups with differing food energy allotments and recorded individual self-selected daily energy intake and lifespan. In study 2, 60 male mice (CD1) were paired and divided into two groups for a 2-week feeding regimen. We evaluated the association between weight gain and food consumption. Within each pair, one animal was randomly assigned to an S group in which the animals had free access to food. The second paired animal (R group) was provided exactly the same diet that their S partner ate the day before. In study 1, across all three groups, we found a significant negative effect of energy intake on lifespan. However, we found a positive association between food intake and lifespan among the ad libitum feeding group: 29·99 (95% CI: 8·2-51·7) days per daily kcal. In study 2, we found a significant (P = 0·003) group (randomized vs. self-selected)-by-food consumption interaction effect on weight gain. At least in nutrition research, associations derived from observational studies may not be reliable indicators of causal effects, even with the most rigorous study designs achievable. © 2016 Stichting European Society for Clinical Investigation Journal Foundation. Published by John Wiley & Sons Ltd.

To dance or not to dance? A comparison of balance, physical fitness and quality of life in older Irish set dancers and age-matched controls.

PubMed

Shanahan, J; Coman, L; Ryan, F; Saunders, J; O'Sullivan, K; Ni Bhriain, O; Clifford, A M

2016-12-01

The objective of this study is to determine if older adults regularly participating in Irish set dancing have superior balance, physical fitness and quality of life compared to age-matched controls. This study used a community-based, observational cross-sectional design. Regular set dancers (n = 39) and age-matched controls (n = 33) were recruited. Participants were assessed using the physical activity scale for the elderly (physical activity levels), mini-BESTest (balance) and senior fitness test (battery of functional fitness tests). Quality of life was also assessed using the EuroQol EQ visual analogue scale. When controlling for between-group differences in levels of physical activity (ANCOVA analysis), the dancers had significantly better balance, functional capacity and quality of life (all P < 0.05) compared to controls. No differences between the groups were observed in other measures of functional fitness. The findings of this study suggest regular participation in set dancing is associated with health benefits for older adults. These results may inform future studies prospectively examining the role of set dancing for falls prevention, emotional well-being and cognitive function in community-dwelling older adults. Copyright © 2016 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

High prevalence and low awareness, treatment and control of hypertension in Asian Indian women.

PubMed

Gupta, R; Pandey, R M; Misra, A; Agrawal, A; Misra, P; Dey, S; Rao, S; Menon, V U; Kamalamma, N; Vasantha Devi, K P; Revathi, K; Vikram, N K; Sharma, V; Guptha, S

2012-10-01

Hypertension is an important public health problem in India. To determine its prevalence, awareness, treatment and control among women, we performed a nationwide study. Population-based studies among women aged 35-70 years were performed in four urban and five rural locations. Stratified sampling was performed and we enrolled 4608 (rural 2604 and urban 2004) of the targeted 8000 (57%). Demographic details, medical history, diet, physical activity, anthropometry and blood pressure (BP) were recorded. Descriptive statistics are reported. Logistic regression was performed to determine the association of hypertension and its awareness, treatment and control with socioeconomic factors. Age-adjusted prevalence of hypertension (known or BP≥140/≥90 mm Hg) was observed in 1672 women (39.2%) (rural 746, 31.5%; urban 926, 48.2%). Significant determinants of hypertension were urban location, greater literacy, high dietary fat, low fibre intake, obesity and truncal obesity (P<0.01). Hypertension awareness was noted in 727 women (42.8%), more in urban (529, 56.8%) than in rural (198, 24.6%). Of these, 38.6% of the women were on treatment (urban 35.7, rural 46.5) and of those treated, controlled blood pressure (<140 and <90 mm Hg) was observed in 21.5% (urban 28.3 vs 10.2). Among hypertensive subjects, treatment was noted in 18.3% (rural 13.1, urban 22.5) and control in 3.9% (rural 1.3, urban 5.9). A significant determinant of low awareness, treatment and control was rural location (multivariate-adjusted P<0.05). There is a high prevalence of hypertension in middle-aged Asian Indian women. Very low awareness, treatment and control status are observed.

FGF receptor genes and breast cancer susceptibility: results from the Breast Cancer Association Consortium

PubMed Central

Agarwal, D; Pineda, S; Michailidou, K; Herranz, J; Pita, G; Moreno, L T; Alonso, M R; Dennis, J; Wang, Q; Bolla, M K; Meyer, K B; Menéndez-Rodríguez, P; Hardisson, D; Mendiola, M; González-Neira, A; Lindblom, A; Margolin, S; Swerdlow, A; Ashworth, A; Orr, N; Jones, M; Matsuo, K; Ito, H; Iwata, H; Kondo, N; Hartman, M; Hui, M; Lim, W Y; T-C Iau, P; Sawyer, E; Tomlinson, I; Kerin, M; Miller, N; Kang, D; Choi, J-Y; Park, S K; Noh, D-Y; Hopper, J L; Schmidt, D F; Makalic, E; Southey, M C; Teo, S H; Yip, C H; Sivanandan, K; Tay, W-T; Brauch, H; Brüning, T; Hamann, U; Dunning, A M; Shah, M; Andrulis, I L; Knight, J A; Glendon, G; Tchatchou, S; Schmidt, M K; Broeks, A; Rosenberg, E H; van't Veer, L J; Fasching, P A; Renner, S P; Ekici, A B; Beckmann, M W; Shen, C-Y; Hsiung, C-N; Yu, J-C; Hou, M-F; Blot, W; Cai, Q; Wu, A H; Tseng, C-C; Van Den Berg, D; Stram, D O; Cox, A; Brock, I W; Reed, M W R; Muir, K; Lophatananon, A; Stewart-Brown, S; Siriwanarangsan, P; Zheng, W; Deming-Halverson, S; Shrubsole, M J; Long, J; Shu, X-O; Lu, W; Gao, Y-T; Zhang, B; Radice, P; Peterlongo, P; Manoukian, S; Mariette, F; Sangrajrang, S; McKay, J; Couch, F J; Toland, A E; Yannoukakos, D; Fletcher, O; Johnson, N; Silva, I dos Santos; Peto, J; Marme, F; Burwinkel, B; Guénel, P; Truong, T; Sanchez, M; Mulot, C; Bojesen, S E; Nordestgaard, B G; Flyer, H; Brenner, H; Dieffenbach, A K; Arndt, V; Stegmaier, C; Mannermaa, A; Kataja, V; Kosma, V-M; Hartikainen, J M; Lambrechts, D; Yesilyurt, B T; Floris, G; Leunen, K; Chang-Claude, J; Rudolph, A; Seibold, P; Flesch-Janys, D; Wang, X; Olson, J E; Vachon, C; Purrington, K; Giles, G G; Severi, G; Baglietto, L; Haiman, C A; Henderson, B E; Schumacher, F; Le Marchand, L; Simard, J; Dumont, M; Goldberg, M S; Labrèche, F; Winqvist, R; Pylkäs, K; Jukkola-Vuorinen, A; Grip, M; Devilee, P; Tollenaar, R A E M; Seynaeve, C; García-Closas, M; Chanock, S J; Lissowska, J; Figueroa, J D; Czene, K; Eriksson, M; Humphreys, K; Darabi, H; Hooning, M J; Kriege, M; Collée, J M; Tilanus-Linthorst, M; Li, J; Jakubowska, A; Lubinski, J; Jaworska-Bieniek, K; Durda, K; Nevanlinna, H; Muranen, T A; Aittomäki, K; Blomqvist, C; Bogdanova, N; Dörk, T; Hall, P; Chenevix-Trench, G; Easton, D F; Pharoah, P D P; Arias-Perez, J I; Zamora, P; Benítez, J; Milne, R L

2014-01-01

Background: Breast cancer is one of the most common malignancies in women. Genome-wide association studies have identified FGFR2 as a breast cancer susceptibility gene. Common variation in other fibroblast growth factor (FGF) receptors might also modify risk. We tested this hypothesis by studying genotyped single-nucleotide polymorphisms (SNPs) and imputed SNPs in FGFR1, FGFR3, FGFR4 and FGFRL1 in the Breast Cancer Association Consortium. Methods: Data were combined from 49 studies, including 53 835 cases and 50 156 controls, of which 89 050 (46 450 cases and 42 600 controls) were of European ancestry, 12 893 (6269 cases and 6624 controls) of Asian and 2048 (1116 cases and 932 controls) of African ancestry. Associations with risk of breast cancer, overall and by disease sub-type, were assessed using unconditional logistic regression. Results: Little evidence of association with breast cancer risk was observed for SNPs in the FGF receptor genes. The strongest evidence in European women was for rs743682 in FGFR3; the estimated per-allele odds ratio was 1.05 (95% confidence interval=1.02–1.09, P=0.0020), which is substantially lower than that observed for SNPs in FGFR2. Conclusion: Our results suggest that common variants in the other FGF receptors are not associated with risk of breast cancer to the degree observed for FGFR2. PMID:24548884

Dipsogenic and feeding influences of intraventricularly infused anionic choline solutions.

PubMed

Mandal, M B; Badgaiyan, R D

1991-10-01

Chloride and bicarbonate solutions of choline were infused into the anteroventral part of the third ventricle of two different groups of rats through chronically implanted stainless steel cannulae. Dipsogenic and feeding responses elicited by these solutions were studied by observations taken at half hour intervals up to two h and then, after 24 h of infusions. Results were compared with the control response evoked by similar infusion of artificial cerebrospinal fluid (aCSF). Food and water intakes were recorded in different groups (n = 18 each) of rats. Dipsogenic response elicited by choline chloride solution in the observation taken 24 h after infusion, however, was higher only as compared to the control. Dipsogenic effect of bicarbonate solution was not significantly different from the control in the first two observations (30 and 60 min), but in the later observations (90, 120 min and 24 h), it was significantly higher. None of the choline solutions significantly alter feeding response within 2 h of infusions. However, in the observation taken 24 h after infusion, the response evoked by choline chloride was greater than that elicited by aCSF. The results support our earlier observation that chloride concentration of third ventricular CSF significantly influences water and food consumption. Intraventricularly administered choline also appears to have positive influence on these behaviors.

Using propensity scores to estimate the effects of insecticides on stream invertebrates from observational data

USGS Publications Warehouse

Lester L. Yuan,; Amina I. Pollard,; Carlisle, Daren M.

2009-01-01

Analyses of observational data can provide insights into relationships between environmental conditions and biological responses across a broader range of natural conditions than experimental studies, potentially complementing insights gained from experiments. However, observational data must be analyzed carefully to minimize the likelihood that confounding variables bias observed relationships. Propensity scores provide a robust approach for controlling for the effects of measured confounding variables when analyzing observational data. Here, we use propensity scores to estimate changes in mean invertebrate taxon richness in streams that have experienced insecticide concentrations that exceed aquatic life use benchmark concentrations. A simple comparison of richness in sites exposed to elevated insecticides with those that were not exposed suggests that exposed sites had on average 6.8 fewer taxa compared to unexposed sites. The presence of potential confounding variables makes it difficult to assert a causal relationship from this simple comparison. After controlling for confounding factors using propensity scores, the difference in richness between exposed and unexposed sites was reduced to 4.1 taxa, a difference that was still statistically significant. Because the propensity score analysis controlled for the effects of a wide variety of possible confounding variables, we infer that the change in richness observed in the propensity score analysis was likely caused by insecticide exposure.

Using propensity scores to estimate the effects of insecticides on stream invertebrates from observational data

USGS Publications Warehouse

Yuan, L.L.; Pollard, A.I.; Carlisle, D.M.

2009-01-01

Analyses of observational data can provide insights into relationships between environmental conditions and biological responses across a broader range of natural conditions than experimental studies, potentially complementing insights gained from experiments. However, observational data must be analyzed carefully to minimize the likelihood that confounding variables bias observed relationships. Propensity scores provide a robust approach for controlling for the effects of measured confounding variables when analyzing observational data. Here, we use propensity scores to estimate changes in mean invertebrate taxon richness in streams that have experienced insecticide concentrations that exceed aquatic life use benchmark concentrations. A simple comparison of richness in sites exposed to elevated insecticides with those that were not exposed suggests that exposed sites had on average 6.8 fewer taxa compared to unexposed sites. The presence of potential confounding variables makes it difficult to assert a causal relationship from this simple comparison. After controlling for confounding factors using propensity scores, the difference in richness between exposed and unexposed sites was reduced to 4.1 taxa, a difference that was still statistically significant. Because the propensity score analysis controlled for the effects of a wide variety of possible confounding variables, we infer that the change in richness observed in the propensity score analysis was likely caused by insecticide exposure. ?? 2009 SETAC.

Indirect Observation in Everyday Contexts: Concepts and Methodological Guidelines within a Mixed Methods Framework

PubMed Central

Anguera, M. Teresa; Portell, Mariona; Chacón-Moscoso, Salvador; Sanduvete-Chaves, Susana

2018-01-01

Indirect observation is a recent concept in systematic observation. It largely involves analyzing textual material generated either indirectly from transcriptions of audio recordings of verbal behavior in natural settings (e.g., conversation, group discussions) or directly from narratives (e.g., letters of complaint, tweets, forum posts). It may also feature seemingly unobtrusive objects that can provide relevant insights into daily routines. All these materials constitute an extremely rich source of information for studying everyday life, and they are continuously growing with the burgeoning of new technologies for data recording, dissemination, and storage. Narratives are an excellent vehicle for studying everyday life, and quantitization is proposed as a means of integrating qualitative and quantitative elements. However, this analysis requires a structured system that enables researchers to analyze varying forms and sources of information objectively. In this paper, we present a methodological framework detailing the steps and decisions required to quantitatively analyze a set of data that was originally qualitative. We provide guidelines on study dimensions, text segmentation criteria, ad hoc observation instruments, data quality controls, and coding and preparation of text for quantitative analysis. The quality control stage is essential to ensure that the code matrices generated from the qualitative data are reliable. We provide examples of how an indirect observation study can produce data for quantitative analysis and also describe the different software tools available for the various stages of the process. The proposed method is framed within a specific mixed methods approach that involves collecting qualitative data and subsequently transforming these into matrices of codes (not frequencies) for quantitative analysis to detect underlying structures and behavioral patterns. The data collection and quality control procedures fully meet the requirement of flexibility and provide new perspectives on data integration in the study of biopsychosocial aspects in everyday contexts. PMID:29441028

Observability-Based Guidance and Sensor Placement

NASA Astrophysics Data System (ADS)

Hinson, Brian T.

Control system performance is highly dependent on the quality of sensor information available. In a growing number of applications, however, the control task must be accomplished with limited sensing capabilities. This thesis addresses these types of problems from a control-theoretic point-of-view, leveraging system nonlinearities to improve sensing performance. Using measures of observability as an information quality metric, guidance trajectories and sensor distributions are designed to improve the quality of sensor information. An observability-based sensor placement algorithm is developed to compute optimal sensor configurations for a general nonlinear system. The algorithm utilizes a simulation of the nonlinear system as the source of input data, and convex optimization provides a scalable solution method. The sensor placement algorithm is applied to a study of gyroscopic sensing in insect wings. The sensor placement algorithm reveals information-rich areas on flexible insect wings, and a comparison to biological data suggests that insect wings are capable of acting as gyroscopic sensors. An observability-based guidance framework is developed for robotic navigation with limited inertial sensing. Guidance trajectories and algorithms are developed for range-only and bearing-only navigation that improve navigation accuracy. Simulations and experiments with an underwater vehicle demonstrate that the observability measure allows tuning of the navigation uncertainty.

Performance monitoring and empathy during active and observational learning in patients with major depression.

PubMed

Thoma, Patrizia; Norra, Christine; Juckel, Georg; Suchan, Boris; Bellebaum, Christian

2015-07-01

Previous literature established a link between major depressive disorder (MDD) and altered reward processing as well as between empathy and (observational) reward learning. The aim of the present study was to assess the effects of MDD on the electrophysiological correlates - the feedback-related negativity (FRN) and the P300 - of active and observational reward processing and to relate them to trait cognitive and affective empathy. Eighteen patients with MDD and 16 healthy controls performed an active and an observational probabilistic reward-learning task while event- related potentials were recorded. Also, participants were assessed with regard to self-reported cognitive and affective trait empathy. Relative to healthy controls, patients with MDD showed overall impaired learning and attenuated FRN amplitudes, irrespective of feedback valence and learning type (active vs. observational), but comparable P300 amplitudes. In the patient group, but not in controls, higher trait perspective taking scores were significantly correlated with reduced FRN amplitudes. The pattern of results suggests impaired prediction error processing and a negative effect of higher trait empathy on feedback-based learning in patients with MDD. Copyright © 2015 Elsevier B.V. All rights reserved.

A New Quality Control Method base on IRMCD for Wind Profiler Observation towards Future Assimilation Application

NASA Astrophysics Data System (ADS)

Chen, Min; Zhang, Yu

2017-04-01

A wind profiler network with a total of 65 profiling radars was operated by the MOC/CMA in China until July 2015. In this study, a quality control procedure is constructed to incorporate the profiler data from the wind-profiling network into the local data assimilation and forecasting system (BJRUC). The procedure applies a blacklisting check that removes stations with gross errors and an outlier check that rejects data with large deviations from the background. Instead of the bi-weighting method, which has been commonly implemented in outlier elimination for one-dimensional scalar observations, an outlier elimination method is developed based on the iterated reweighted minimum covariance determinant (IRMCD) for multi-variate observations such as wind profiler data. A quality control experiment is separately performed for subsets containing profiler data tagged in parallel with/without rain flags at every 00UTC/12UTC from 20 June to 30 Sep 2015. From the results, we find that with the quality control, the frequency distributions of the differences between the observations and model background become more Gaussian-like and meet the requirements of a Gaussian distribution for data assimilation. Further intensive assessment for each quality control step reveals that the stations rejected by blacklisting contain poor data quality, and the IRMCD rejects outliers in a robust and physically reasonable manner.

Fluid Mechanics of Wing Adaptation for Separation Control

NASA Technical Reports Server (NTRS)

Chandrasekhara, M. S.; Wilder, M. C.; Carr, L. W.; Davis, Sanford S. (Technical Monitor)

1997-01-01

The unsteady fluid mechanics associated with use of a dynamically deforming leading edge airfoil for achieving compressible flow separation control has been experimentally studied. Changing the leading edge curvature at rapid rates dramatically alters the flow vorticity dynamics which is responsible for the many effects observed in the flow.

Language Switching across Modalities: Evidence from Bimodal Bilinguals

ERIC Educational Resources Information Center

Dias, Patricia; Villameriel, Saúl; Giezen, Marcel R.; Costello, Brendan; Carreiras, Manuel

2017-01-01

This study investigated whether language control during language production in bilinguals generalizes across modalities, and to what extent the language control system is shaped by competition for the same articulators. Using a cued language-switching paradigm, we investigated whether switch costs are observed when hearing signers switch between a…

Predicting Preschool Effortful Control from Toddler Temperament and Parenting Behavior

ERIC Educational Resources Information Center

Cipriano, Elizabeth A.; Stifter, Cynthia A.

2010-01-01

This longitudinal study assessed whether maternal behavior and emotional tone moderated the relationship between toddler temperament and preschooler's effortful control. Maternal behavior and emotional tone were observed during a parent-child competing demands task when children were 2 years of age. Child temperament was also assessed at 2 years…

Parental Control is Not Unconditionally Detrimental for Externalizing Behaviors in Early Childhood

ERIC Educational Resources Information Center

Akcinar, Berna; Baydar, Nazli

2014-01-01

The association of three different strategies of maternal control (behavioral, psychological, and physical), and maternal warmth with children's externalizing behaviors were analyzed in an observational study of 3-year-old children in Turkey ("N" = 123). The results indicated that (i) mothers exercised all three types of control…

A comparative study: use of a Brain-computer Interface (BCI) device by people with cerebral palsy in interaction with computers.

PubMed

Heidrich, Regina O; Jensen, Emely; Rebelo, Francisco; Oliveira, Tiago

2015-01-01

This article presents a comparative study among people with cerebral palsy and healthy controls, of various ages, using a Brain-computer Interface (BCI) device. The research is qualitative in its approach. Researchers worked with Observational Case Studies. People with cerebral palsy and healthy controls were evaluated in Portugal and in Brazil. The study aimed to develop a study for product evaluation in order to perceive whether people with cerebral palsy could interact with the computer and compare whether their performance is similar to that of healthy controls when using the Brain-computer Interface. Ultimately, it was found that there are no significant differences between people with cerebral palsy in the two countries, as well as between populations without cerebral palsy (healthy controls).

"Lies, damned lies ..." and observational studies in comparative effectiveness research.

PubMed

Albert, Richard K

2013-06-01

A new federal initiative has allocated $1.1 billion to comparative effectiveness research, and many have emphasized the importance of including observational studies in this effort. The rationale for using observational studies to assess comparative effectiveness is based on concerns that randomized controlled trials (RCTs) are not "real world" because they enroll homogeneous patient populations, measure study outcomes that are not important to patients, use protocols that are overly complex, are conducted in specialized centers, and use study treatments that are not consistent with usual care, and that RCTs are not always feasible because of a lack of equipoise, the need to assess delayed endpoints, and concerns that they take years to complete and are expensive. This essay questions the validity of each of these proposed limitations, summarizes concerns raised about the accuracy of results generated by observational studies, provides some examples of discrepancies between results of observational studies and RCTs that pertain to pulmonary and critical care, and suggests that using observational studies for comparative effectiveness research may increase rather than decrease the cost of health care and may harm patients.

Lifestyle factors and risk of leukemia and non-Hodgkin's lymphoma: a case-control study.

PubMed

Parodi, Stefano; Santi, Irene; Marani, Enza; Casella, Claudia; Puppo, Antonella; Garrone, Elsa; Fontana, Vincenzo; Stagnaro, Emanuele

2016-03-01

Risk factors for leukemia and lymphomas in adults are largely unknown. This study was aimed at evaluating the association between lifestyle factors and the risk of hematological malignancies in an adult population. Data were drawn from a population-based case-control study carried out in Italy and included 294 cases (199 lymphoid and 95 myeloid) and 279 controls. Analyses were performed using standard multivariable logistic regression. Hair dye use for at least 15 years was associated with a higher risk of lymphoid malignancies among females (OR 2.3, 95 % CI 1.0-4.9, p = 0.036, test for trend). Furthermore, a protective effect of a moderate to heavy tea consumption on the risk of myeloid malignancies was observed (OR 0.4, 95 % CI 0.2-0.9, p = 0.017). No association was found for the use of alcoholic beverages and tobacco smoking. Our results confirm the potential carcinogenic effect of prolonged hair dye use observed in previous investigations. The excess risk could be explained by exposure to a higher concentration of toxic compounds in hair products used in the past. The protective effect of regular tea consumption observed in an area with a very high prevalence of black tea consumers deserves further investigation.

Microstructural and ultrastructural assessment of inferior alveolar nerve damage following nerve lateralization and implant placement: an experimental study in rabbits.

PubMed

Yoshimoto, Marcelo; Watanabe, Il-sei; Martins, Marília T; Salles, Marcos B; Ten Eyck, Gary R; Coelho, Paulo G

2009-01-01

The present study assessed damage to the inferior alveolar nerve (IAN) following nerve lateralization and implant placement surgery through optical and transmission electron microscopy (TEM). IAN lateralization was performed in 16 adult female rabbits (Oryctolagus cuniculus). During the nerve lateralization procedure, one implant was placed through the mandibular canal, and the IAN was replaced in direct contact with the implant. The implant was placed in the right mandible, and the left side was used as a control (no surgical procedure). After 8 weeks, the animals were sacrificed and samples were prepared for optical and TEM analysis of IAN structural damage. Histomorphometric analysis was performed to determine the number and cross-sectional dimensions of nerve fascicles and myelin sheath thickness between experimental and control groups. The different parameters were compared by one-way analysis of variance at the 95% significance level. Alterations in the perineural and endoneural regions of the IAN, with higher degrees of vascularization, were observed in the experimental group. TEM showed that the majority of the myelinated nerve fibers were not affected in the experimental samples. No significant variation in the number of fascicles was observed, significantly larger fascicle height and width were observed in the control group, and significantly thicker myelin sheaths were observed in the experimental samples. IAN lateralization resulted in substantial degrees of tissue disorganization at the microstructural level because of the presence of edema. However, at the ultrastructural level, small amounts of fiber degeneration were observed.

Associations between otitis media and child behavioural and learning difficulties: Results from a Danish cohort.

PubMed

Niclasen, J; Obel, C; Homøe, P; Kørvel-Hanquist, A; Dammeyer, J

2016-05-01

Findings from studies investigating early childhood episodes of otitis media (OM) and developmental outcomes are inconclusive. This may in part be because large-scale prospective studies controlling for relevant confounding factors are sparse. The present study investigates associations between OM in early childhood and later behavioural and learning difficulties controlling for relevant confounding factors. The study applied data from the Aarhus Birth Cohort's 10-12-year-old follow-up (N=7578). Associations between retrospective parent-reported OM (no OM; 1-3 episodes of OM with/without tympanostomy tubes; 4+ OM episodes without tympanostomy tubes and; 4+ OM episodes with tympanostomy tubes) one the one hand, and parent- and teacher-reported scores on the Strengths and Difficulties Questionnaire (SDQ) and parent-reported academic difficulties on the other hand, were investigated. The following variables were controlled for: parental educational level, maternal and paternal school problems, parental post-natal smoking, breastfeeding, and age at which the child started walking. All analyses were stratified by gender. Large differences in background characteristics were observed for the group of children with 4+ OM episodes with tympanostomy tubes compared to the no OM group. After controlling for relevant confounders, negative associations were consistently observed for the group of children with 4+ episodes of OM with tympanostomy tubes compared to the group of children without OM. This was particularly so for girls. The findings suggest an association between 4+ episodes of early OM with tympanostomy tubes and behavioural and learning difficulties later in childhood. The large inter-group differences, i.e. impact of residual and unmeasured confounding factors, may in part explain the observed associations and underline the need to include these in future studies. Copyright © 2016. Published by Elsevier Ireland Ltd.

A Probability Analysis of Historical Pregnancy and Fetal Data from Dutch Belted and New Zealand White Rabbit Strains from Embryo-Fetal Development Studies.

PubMed

Posobiec, Lorraine M; Cox, Estella M; Solomon, Howard M; Lewis, Elise M; Wang, Kai-fen; Stanislaus, Dinesh

2016-04-01

Embryo-fetal development (EFD) studies, typically in pregnant rats and rabbits, are conducted prior to enrolling females of reproductive age in clinical trials. Common rabbit strains used are the New Zealand White (NZW) and Dutch Belted (DB). As fetal abnormalities can occur in all groups, including controls, Historical Control Data (HCD) is compiled using data from control groups of EFD studies, and is used along with each study's concurrent control group to help determine whether fetal abnormalities are caused by the test article or are part of background incidences. A probability analysis was conducted on 2014 HCD collected at Charles River Inc., Horsham PA on Covance NZW, Covance DB, and Charles River (CR) NZW rabbits. The analysis was designed to determine the probability of 2 or 3 out of a group of 22 does aborting their litter or of having a fetal abnormality by chance. Results demonstrate that pregnancy parameters and fetal observations differ not only between strains, but between sources of rabbits of the same strain. As a result the probability of these observations occurring by chance in two or three litters was drastically different. Although no one single strain is perfect, this analysis highlights the need to appreciate the inherent differences in pregnancy and fetal abnormalities between strains, and points out that an apparent isolated increased incidence of an observation in one strain will not necessarily be test-article related in another strain. A robust HCD is critical for interpretation of EFD rabbit studies, regardless of the rabbit strain used. © 2016 Wiley Periodicals, Inc.

Relationship Between Serum Zinc Level and Metabolic Syndrome: A Meta-Analysis of Observational Studies.

PubMed

Zhang, Yi; Zhang, Dian-Zhong

2018-05-10

This research sought to summarize the evidence regarding the relationship between serum zinc level and metabolic syndrome (MetS). The electronic databases of PubMed, Web of Science, and Embase were searched up to October 2017 for observational studies on the association between serum zinc level and MetS. The standard mean difference (SMD) and its corresponding 95% confidence interval (CI) of the serum zinc level for MetS versus control participants were calculated. In addition, the pooled odds ratio (OR) and relative risk (RR) of MetS for the highest versus lowest category of serum zinc level, as well as their corresponding 95% CI, were also calculated. A total of 11 observational studies (8 cross-sectional, 1 case-control, and 2 cohort studies) were included in this meta-analysis. The combined SMD demonstrated that the serum zinc level in MetS was higher than that in control participants (SMD = 0.11; 95% CI, 0.03-0.19; p = 0.009). Moreover, the overall multivariable-adjusted RR showed that the increased serum zinc level was associated with a higher risk of MetS (RR = 1.82; 95% CI, 1.33-2.50; p < 0.001). On the contrary, the overall multivariable-adjusted OR showed that there was no significant relationship between serum zinc level and MetS (OR = 1.00; 95% CI, 0.99-1.01; p = 0.841). Although the serum zinc level in participants with MetS was significantly higher than that in control ones, the existing evidence was still insufficient to conclude a definite relationship between serum zinc level and MetS. More well-designed prospective cohort studies are needed to elaborate the concerned issues further.

Effects of health education intervention on negative emotion and quality of life of patients with laryngeal cancer after postoperative radiotherapy.

PubMed

Han, J; Nian, H; Zheng, Z-Y; Zhao, M-M; Xu, D; Wang, C

2018-02-01

The study aimed to explore and analyze the effects of health education intervention on patients with laryngeal cancer and evaluate negative emotions and quality of life after receiving postoperative radiotherapy. Furthermore the relationship between health education intervention methods and its correlation to complications and relapse rates require greater understanding. Patients with aryngeal cancer receiving surgery and postoperative radiotherapy were randomly divided into observation and control groups. A quality of life questionnaire was used to evaluate patients' current life quality as well as negative emotions experienced. The collected data was evaluated using the Self-rating Anxiety Scale (SAS) as well as the Self-rating Depression Scale (SDS). At the time of discharge, patients' satisfaction on nursing and perception of health knowledge was assessed. Three and six months after discharge, patients were given follow-up visits and questionnaire surveys to evaluate their rehabilitation. This was done in relation with the Morningside Rehabilitation Stats Scale (MRSS), incidence of complications and recurrence. The scores of negative emotions, exhibited during the study, were lower in the observation group than in the control group. A month after discharge had a positive correlation to improved quality of life. This was highlighted in the observation group in comparison with the control group. The data collected following discharge revealed an improvement in quality of life, compared with that at the time of admission. Compared with the control group, the SAS and SDS scores in the observation group were decreased a month after discharge. Compared with the scores on admission, the SAS and SDS scores in both groups were decreased one month after discharge. The observation group had a lower incidence of complications than that of the control group. Six months after discharge, in the observation group, the MRSS score was lower than before discharge while in the control group, the MRSS score was higher than before discharge. Health education intervention can significantly improve the quality of life and reduce experiences relating to negative emotion in patients with laryngeal cancer. This improvement was seen following surgery and radiotherapy. Additionally effective reduction rates in the incidence of postoperative complications and recurrence were exhibited following methods of health education intervention. Copyright © 2017 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

A general observatory control software framework design for existing small and mid-size telescopes

NASA Astrophysics Data System (ADS)

Ge, Liang; Lu, Xiao-Meng; Jiang, Xiao-Jun

2015-07-01

A general framework for observatory control software would help to improve the efficiency of observation and operation of telescopes, and would also be advantageous for remote and joint observations. We describe a general framework for observatory control software, which considers principles of flexibility and inheritance to meet the expectations from observers and technical personnel. This framework includes observation scheduling, device control and data storage. The design is based on a finite state machine that controls the whole process.

Clinical Impact Research – how to choose experimental or observational intervention study?

PubMed Central

Malmivaara, Antti

2016-01-01

Abstract Background: Interventions directed to individuals by health and social care systems should increase health and welfare of patients and customers. Aims: This paper aims to present and define a new concept Clinical Impact Research (CIR) and suggest which study design, either randomized controlled trial (RCT) (experimental) or benchmarking controlled trial (BCT) (observational) is recommendable and to consider the feasibility, validity, and generalizability issues in CIR. Methods: The new concept is based on a narrative review of the literature and on author’s idea that in intervention studies, there is a need to cover comprehensively all the main impact categories and their respective outcomes. The considerations on how to choose the most appropriate study design (RCT or BCT) were based on previous methodological studies on RCTs and BCTs and on author’s previous work on the concepts benchmarking controlled trial and system impact research (SIR). Results: The CIR covers all studies aiming to assess the impact for health and welfare of any health (and integrated social) care or public health intervention directed to an individual. The impact categories are accessibility, quality, equality, effectiveness, safety, and efficiency. Impact is the main concept, and within each impact category, both generic- and context-specific outcome measures are needed. CIR uses RCTs and BCTs. Conclusions: CIR should be given a high priority in medical, health care, and health economic research. Clinicians and leaders at all levels of health care can exploit the evidence from CIR. Key messagesThe new concept of Clinical Impact Research (CIR) is defined as a research field aiming to assess what are the impacts of healthcare and public health interventions targeted to patients or individuals.The term impact refers to all effects caused by the interventions, with particular emphasis on accessibility, quality, equality, effectiveness, safety, and efficiency. CIR uses two study designs: randomized controlled trials (RCTs) (experimental) and benchmarking controlled trials (BCTs) (observational). Suggestions on how to choose between RCT and BCT as the most suitable study design are presented.Simple way of determining the study question in CIR based on the PICO (patient, intervention, control intervention, outcome) framework is presented.CIR creates the scientific basis for clinical decisions. Clinicians and leaders at all levels of health care and those working for public health can use the evidence from CIR for the benefit of patients and the population. PMID:27494394

Clinical Impact Research - how to choose experimental or observational intervention study?

PubMed

Malmivaara, Antti

2016-11-01

Interventions directed to individuals by health and social care systems should increase health and welfare of patients and customers. This paper aims to present and define a new concept Clinical Impact Research (CIR) and suggest which study design, either randomized controlled trial (RCT) (experimental) or benchmarking controlled trial (BCT) (observational) is recommendable and to consider the feasibility, validity, and generalizability issues in CIR. The new concept is based on a narrative review of the literature and on author's idea that in intervention studies, there is a need to cover comprehensively all the main impact categories and their respective outcomes. The considerations on how to choose the most appropriate study design (RCT or BCT) were based on previous methodological studies on RCTs and BCTs and on author's previous work on the concepts benchmarking controlled trial and system impact research (SIR). The CIR covers all studies aiming to assess the impact for health and welfare of any health (and integrated social) care or public health intervention directed to an individual. The impact categories are accessibility, quality, equality, effectiveness, safety, and efficiency. Impact is the main concept, and within each impact category, both generic- and context-specific outcome measures are needed. CIR uses RCTs and BCTs. CIR should be given a high priority in medical, health care, and health economic research. Clinicians and leaders at all levels of health care can exploit the evidence from CIR. Key messages The new concept of Clinical Impact Research (CIR) is defined as a research field aiming to assess what are the impacts of healthcare and public health interventions targeted to patients or individuals. The term impact refers to all effects caused by the interventions, with particular emphasis on accessibility, quality, equality, effectiveness, safety, and efficiency. CIR uses two study designs: randomized controlled trials (RCTs) (experimental) and benchmarking controlled trials (BCTs) (observational). Suggestions on how to choose between RCT and BCT as the most suitable study design are presented. Simple way of determining the study question in CIR based on the PICO (patient, intervention, control intervention, outcome) framework is presented. CIR creates the scientific basis for clinical decisions. Clinicians and leaders at all levels of health care and those working for public health can use the evidence from CIR for the benefit of patients and the population.

Possible causes of variation in acrylamide concentration in French fries prepared in food service establishments: an observational study.

PubMed

Sanny, M; Jinap, S; Bakker, E J; van Boekel, M A J S; Luning, P A

2012-05-01

Acrylamide is a probable human carcinogen, and its presence in a range of fried and oven-cooked foods has raised considerable health concern world-wide. Dietary intake studies observed significant variations in acrylamide concentrations, which complicate risk assessment and the establishment of effective control measures. The objective of this study was to obtain an insight into the actual variation in acrylamide concentrations in French fries prepared under typical conditions in a food service establishment (FSE). Besides acrylamide, frying time, frying temperature, and reducing sugars were measured and the actual practices at receiving, thawing and frying during French fries preparation were observed and recorded. The variation in the actual frying temperature contributed most to the variation in acrylamide concentrations, followed by the variation in actual frying time; no obvious effect of reducing sugars was found. The lack of standardised control of frying temperature and frying time (due to inadequate frying equipment) and the variable practices of food handlers seem to contribute most to the large variation and high acrylamide concentrations in French fries prepared in a restaurant type of FSE as compared to chain fast-food services, and institutional caterers. The obtained insights in this study can be used to develop dedicated control measures in FSE, which may contribute to a sustainable reduction in the acrylamide intake. Copyright © 2011 Elsevier Ltd. All rights reserved.

A theory of eu-estrogenemia: a unifying concept

PubMed Central

Turner, Ralph J.; Kerber, Irwin J.

2017-01-01

Abstract Objective: The aim of the study was to propose a unifying theory for the role of estrogen in postmenopausal women through examples in basic science, randomized controlled trials, observational studies, and clinical practice. Methods: Review and evaluation of the literature relating to estrogen. Discussion: The role of hormone therapy and ubiquitous estrogen receptors after reproductive senescence gains insight from basic science models. Observational studies and individualized patient care in clinical practice may show outcomes that are not reproduced in randomized clinical trials. The understanding gained from the timing hypothesis for atherosclerosis, the critical window theory in neurosciences, randomized controlled trials, and numerous genomic and nongenomic actions of estrogen discovered in basic science provides new explanations to clinical challenges that practitioners face. Consequences of a hypo-estrogenemic duration in women's lives are poorly understood. The Study of Women Across the Nation suggests its magnitude is greater than was previously acknowledged. We propose that the healthy user bias was the result of surgical treatment (hysterectomy with oophorectomy) for many gynecological maladies followed by pharmacological and physiological doses of estrogen to optimize patient quality of life. The past decade of research has begun to demonstrate the role of estrogen in homeostasis. Conclusions: The theory of eu-estrogenemia provides a robust framework to unify the timing hypothesis, critical window theory, randomized controlled trials, the basic science of estrogen receptors, and clinical observations of patients over the past five decades. PMID:28562489

Boys' serotonin transporter genotype affects maternal behavior through self-control: a case of evocative gene-environment correlation.

PubMed

Pener-Tessler, Roni; Avinun, Reut; Uzefovsky, Florina; Edelman, Shany; Ebstein, Richard P; Knafo, Ariel

2013-02-01

Self-control, involving processes such as delaying gratification, concentrating, planning, following instructions, and adapting emotions and behavior to situational requirements and social norms, may have a profound impact on children's adjustment. The importance of self-control suggests that parents are likely to modify their parenting based on children's ability for self-control. We study the effect of children's self-control, a trait partially molded by genetics, on their mothers' parenting, a process of evocative gene-environment correlation. Israeli 3.5-year-old twins (N = 320) participated in a lab session in which their mothers' parenting was observed. DNA was available from most children (N = 228). Mothers described children's self-control in a questionnaire. Boys were lower in self-control and received less positive parenting from their mothers, in comparison with girls. For boys, and not for girls, the serotonin transporter linked polymorphic region gene predicted mothers' levels of positive parenting, an effect mediated by boys' self-control. The implications of this evocative gene-environment correlation and the observed sex differences are discussed.

Studies in useful hard x-ray induced chemistry

NASA Astrophysics Data System (ADS)

Pravica, Michael; Bai, Ligang; Sneed, Daniel; Park, Changyong

2013-06-01

The observed rapid decomposition of potassium chlorate (via 2KClO3 + h ν --> 2KCl +3O2) via synchrotron hard x-ray irradiation (>10 keV) has enabled experiments that are developing novel and useful hard x-ray chemistry. We have observed a number of radiation-induced in situ decomposition reactions in various substances which release O2, H2, N2, NH3, and H2O in a diamond anvil cell (DAC) at ambient and high pressures. These novel acatalytic and isothermal reactions represent a highly controllable, penetrating, and focused method to initiate chemistry (including x-ray induced combustion) in sealed and/or isolated chambers which maintain matter under extreme conditions. During our studies, we have typically observed a slowing of decomposition with pressure including phase dependent decomposition of KClO3. Energy dependent studies have observed an apparent resonance near 15 keV at which the decomposition rate is maximized. This may enable use of much lower flux and portable x-ray sources (e.g. x-ray tubes) in larger scale experiments. These developments support novel means to load DACs and control chemical reactions providing novel routes of synthesis of novel materials under extreme conditions.

Controllers, observers, and applications thereof

NASA Technical Reports Server (NTRS)

Gao, Zhiqiang (Inventor); Zhou, Wankun (Inventor); Miklosovic, Robert (Inventor); Radke, Aaron (Inventor); Zheng, Qing (Inventor)

2011-01-01

Controller scaling and parameterization are described. Techniques that can be improved by employing the scaling and parameterization include, but are not limited to, controller design, tuning and optimization. The scaling and parameterization methods described here apply to transfer function based controllers, including PID controllers. The parameterization methods also apply to state feedback and state observer based controllers, as well as linear active disturbance rejection (ADRC) controllers. Parameterization simplifies the use of ADRC. A discrete extended state observer (DESO) and a generalized extended state observer (GESO) are described. They improve the performance of the ESO and therefore ADRC. A tracking control algorithm is also described that improves the performance of the ADRC controller. A general algorithm is described for applying ADRC to multi-input multi-output systems. Several specific applications of the control systems and processes are disclosed.

[Locus of control and self-concept in interpersonal conflict resolution approaches].

PubMed

Hisli Sahin, Nesrin; Basim, H Nejat; Cetin, Fatih

2009-01-01

The purpose of this study was to investigate the relationship between self-concept and locus of control in interpersonal conflict resolution approaches and to determine the predictors of conflict resolution approach choices. The study included 345 students aged between 18 and 28 years that were studying at universities in Ankara. Data were collected using the Interpersonal Conflict Resolution Approaches Scale to measure conflict resolution approaches, the Social Comparison Scale to measure self-concept, and the Internal-External Locus of Control Scale to measure locus of control. It was observed that confrontation approach to interpersonal conflict was predicted by self-concept (beta = 0.396, P < 0.001) Moreover, self-concept was related to self-disclosure (beta = 0.180, P < 0.01) and emotional expression (beta = 0.196, P < 0.001) approaches. Locus of control played a role in the choice of all resolution approaches. In addition to these findings, it was observed that females used self-disclosure (beta = -0.163, P < 0.01) and emotional expression (beta = -0.219, P < 0.001), while males used approach (beta = 0.395, P < 0.001) and public behavior (beta = 0.270, P < 0.001) approaches in the resolution processes. Self-concept and locus of control were related to the behaviors adopted in the interpersonal conflict resolution process. Individuals with a positive self-concept and an internal locus of control adopted solutions to interpersonal conflict resolution that were more effective and constructive.

Offspring Outcomes in Studies of Antidepressant-Treated Pregnancies Depend on the Choice of Control Group.

PubMed

Andrade, Chittaranjan

2017-03-01

Antenatal depression complicates 14%-23% of pregnancies; if the depression is left untreated, there is an increased risk of a wide range of adverse maternal and offspring outcomes. However, antidepressant use, and, more specifically, selective serotonin reuptake inhibitor (SSRI) use, has also been associated with adverse pregnancy outcomes. Regrettably, SSRIs have received bad press in this context even though the evidence linking them with the adverse outcomes has not disentangled depression effects from drug effects. The most important reason why depression and drug effects cannot be separated is that the evidence is derived mostly from retrospective observational studies and not from randomized controlled trials, which are necessary but which cannot be performed during pregnancy for ethical and practical reasons. In these observational studies, the control groups are formed from healthy women, depressed women, and/or propensity score-matched women who did not receive antidepressant drugs during pregnancy. A limitation of such control groups is that they cannot control for confounding arising from poorly measured, unmeasured, or unknown variables that influence the pregnancy outcomes being assessed. This article discusses problems involved in such research and illustrates how, when confounding is diminished by using sibling controls discordant for antidepressant exposure during pregnancy, the risks of adverse outcomes associated with antidepressant exposure diminish. However, a discordant sibling control group is associated with its own limitations, and these are also discussed. © Copyright 2017 Physicians Postgraduate Press, Inc.

Prevalence of radiographic hip osteoarthritis is increased in high bone mass.

PubMed

Hardcastle, S A; Dieppe, P; Gregson, C L; Hunter, D; Thomas, G E R; Arden, N K; Spector, T D; Hart, D J; Laugharne, M J; Clague, G A; Edwards, M H; Dennison, E M; Cooper, C; Williams, M; Davey Smith, G; Tobias, J H

2014-08-01

Epidemiological studies have shown an association between increased bone mineral density (BMD) and osteoarthritis (OA), but whether this represents cause or effect remains unclear. In this study, we used a novel approach to investigate this question, determining whether individuals with High Bone Mass (HBM) have a higher prevalence of radiographic hip OA compared with controls. HBM cases came from the UK-based HBM study: HBM was defined by BMD Z-score. Unaffected relatives of index cases were recruited as family controls. Age-stratified random sampling was used to select further population controls from the Chingford and Hertfordshire cohort studies. Pelvic radiographs were pooled and assessed by a single observer blinded to case-control status. Analyses used logistic regression, adjusted for age, gender and body mass index (BMI). 530 HBM hips in 272 cases (mean age 62.9 years, 74% female) and 1702 control hips in 863 controls (mean age 64.8 years, 84% female) were analysed. The prevalence of radiographic OA, defined as Croft score ≥3, was higher in cases compared with controls (20.0% vs 13.6%), with adjusted odds ratio (OR) [95% CI] 1.52 [1.09, 2.11], P = 0.013. Osteophytes (OR 2.12 [1.61, 2.79], P < 0.001) and subchondral sclerosis (OR 2.78 [1.49, 5.18], P = 0.001) were more prevalent in cases. However, no difference in the prevalence of joint space narrowing (JSN) was seen (OR 0.97 [0.72, 1.33], P = 0.869). An increased prevalence of radiographic hip OA and osteophytosis was observed in HBM cases compared with controls, in keeping with a positive association between HBM and OA and suggesting that OA in HBM has a hypertrophic phenotype. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Association between plant-based diets and plasma lipids: a systematic review and meta-analysis.

PubMed

Yokoyama, Yoko; Levin, Susan M; Barnard, Neal D

2017-09-01

Although a recent meta-analysis of randomized controlled trials showed that adoption of a vegetarian diet reduces plasma lipids, the association between vegetarian diets and long-term effects on plasma lipids has not been subjected to meta-analysis. The aim was to conduct a systematic review and meta-analysis of observational studies and clinical trials that have examined associations between plant-based diets and plasma lipids. MEDLINE, Web of Science, and the Cochrane Central Register of Controlled Trials were searched for articles published in English until June 2015. The literature was searched for controlled trials and observational studies that investigated the effects of at least 4 weeks of a vegetarian diet on plasma lipids. Two reviewers independently extracted the study methodology and sample size, the baseline characteristics of the study population, and the concentrations and variance measures of plasma lipids. Mean differences in concentrations of plasma lipids between vegetarian and comparison diet groups were calculated. Data were pooled using a random-effects model. Of the 8385 studies identified, 30 observational studies and 19 clinical trials met the inclusion criteria (N = 1484; mean age, 48.6 years). Consumption of vegetarian diets was associated with lower mean concentrations of total cholesterol (-29.2 and -12.5 mg/dL, P < 0.001), low-density lipoprotein cholesterol (-22.9 and -12.2 mg/dL, P < 0.001), and high-density lipoprotein cholesterol (-3.6 and -3.4 mg/dL, P < 0.001), compared with consumption of omnivorous diets in observational studies and clinical trials, respectively. Triglyceride differences were -6.5 (P = 0.092) in observational studies and 5.8 mg/dL (P = 0.090) in intervention trials. Plant-based diets are associated with decreased total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol, but not with decreased triglycerides. PROSPERO number CRD42015023783. Available at: https://www.crd.york.ac.uk/PROSPERO/display_record.asp?ID=CRD42015023783. © The Author(s) 2017. Published by Oxford University Press on behalf of the International Life Sciences Institute.

The relationship between urban environment and the inflammatory bowel diseases: a systematic review and meta-analysis.

PubMed

Soon, Ing Shian; Molodecky, Natalie A; Rabi, Doreen M; Ghali, William A; Barkema, Herman W; Kaplan, Gilaad G

2012-05-24

The objective of this study was to conduct a systematic review with meta-analysis of studies assessing the association between living in an urban environment and the development of the Crohn's disease (CD) or ulcerative colitis (UC). A systematic literature search of MEDLINE (1950-Oct. 2009) and EMBASE (1980-Oct. 2009) was conducted to identify studies investigating the relationship between urban environment and IBD. Cohort and case-control studies were analyzed using incidence rate ratio (IRR) or odds ratio (OR) with 95 % confidence intervals (CIs), respectively. Stratified and sensitivity analyses were performed to explore heterogeneity between studies and assess effects of study quality. The search strategy retrieved 6940 unique citations and 40 studies were selected for inclusion. Of these, 25 investigated the relationship between urban environment and UC and 30 investigated this relationship with CD. Included in our analysis were 7 case-control UC studies, 9 case-control CD studies, 18 cohort UC studies and 21 cohort CD studies. Based on a random effects model, the pooled IRRs for urban compared to rural environment for UC and CD studies were 1.17 (1.03, 1.32) and 1.42 (1.26, 1.60), respectively. These associations persisted across multiple stratified and sensitivity analyses exploring clinical and study quality factors. Heterogeneity was observed in the cohort studies for both UC and CD, whereas statistically significant heterogeneity was not observed for the case-control studies. A positive association between urban environment and both CD and UC was found. Heterogeneity may be explained by differences in study design and quality factors.

Evidence for a Heritable Brain Basis to Deviance-Promoting Deficits in Self-Control.

PubMed

Yancey, James R; Venables, Noah C; Hicks, Brian M; Patrick, Christopher J

2013-01-01

Classic criminological theories emphasize the role of impaired self-control in behavioral deviancy. Reduced amplitude of the P300 brain response is reliably observed in individuals with antisocial and substance-related problems, suggesting it may serve as a neurophysiological indicator of deficiencies in self-control that confer liability to deviancy. The current study evaluated the role of self-control capacity - operationalized by scores on a scale measure of trait disinhibition - in mediating the relationship between P300 brain response and behavioral deviancy in a sample of adult twins ( N =419) assessed for symptoms of antisocial/addictive disorders and P300 brain response. As predicted, greater disorder symptoms and higher trait disinhibition scores each predicted smaller P300 amplitude, and trait disinhibition mediated observed relations between antisocial/addictive disorders and P300 response. Further, twin modeling analyses revealed that trait disinhibition scores and disorder symptoms reflected a common genetic liability, and this genetic liability largely accounted for the observed phenotypic relationship between antisocial-addictive problems and P300 brain response. These results provide further evidence that heritable weaknesses in self-control capacity confer liability to antisocial/addictive outcomes and that P300 brain response indexes this dispositional liability.

Combination therapy with GLP-1 receptor agonists and basal insulin: a systematic review of the literature

PubMed Central

Balena, R; Hensley, I E; Miller, S; Barnett, A H

2013-01-01

Treatment algorithms for type 2 diabetes call for intensification of therapy over time as the disease progresses and glycaemic control worsens. If diet, exercise and oral antihyperglycaemic medications (OAMs) fail to maintain glycaemic control then basal insulin is added and ultimately prandial insulin may be required. However, such an intensification strategy carries risk of increased hypoglycaemia and weight gain, both of which are associated with worse long-term outcomes. An alternative strategy is to intensify therapy by the addition of a short-acting glucagon-like peptide-1 receptor agonist (GLP-1 RA) rather than prandial insulin. Short-acting GLP-1 RAs such as exenatide twice daily are particularly effective at reducing postprandial glucose while basal insulin has a greater effect on fasting glucose, providing a physiological rationale for this complementary approach. This review analyzes the latest randomized controlled clinical trials of insulin/GLP-1 RA combination therapy and examines results from ‘real-world’ use of the combinations as reported through observational and clinical practice studies. The most common finding across all types of studies was that combination therapy improved glycaemic control without weight gain or an increased risk of hypoglycaemia. Many studies reported weight loss and a reduction in insulin use when a GLP-1 RA was added to existing insulin therapy. Overall, the relative degree of benefit to glycaemic control and weight was influenced by the insulin titration employed in conjunction with the GLP-1 RA. The greatest glycaemic benefits were observed in studies with structured titration of insulin to glycaemic targets while the greatest weight benefits were observed in studies with a protocol-specified focus on insulin sparing. The adverse event profile of GLP-1 RAs in the reviewed trials was similar to that reported with GLP-1 RAs as monotherapy or in combination with OAMs with gastrointestinal events being the most commonly reported. PMID:23061470

Reduced posterior parietal cortex activation after training on a visual search task.

PubMed

Bueichekú, Elisenda; Miró-Padilla, Anna; Palomar-García, María-Ángeles; Ventura-Campos, Noelia; Parcet, María-Antonia; Barrós-Loscertales, Alfonso; Ávila, César

2016-07-15

Gaining experience on a cognitive task improves behavioral performance and is thought to enhance brain efficiency. Despite the body of literature already published on the effects of training on brain activation, less research has been carried out on visual search attention processes under well controlled conditions. Thirty-six healthy adults divided into trained and control groups completed a pre-post letter-based visual search task fMRI study in one day. Twelve letters were used as targets and ten as distractors. The trained group completed a training session (840 trials) with half the targets between scans. The effects of training were studied at the behavioral and brain levels by controlling for repetition effects using both between-subjects (trained vs. control groups) and within-subject (trained vs. untrained targets) controls. The trained participants reduced their response speed by 31% as a result of training, maintaining their accuracy scores, whereas the control group hardly changed. Neural results revealed that brain changes associated with visual search training were circumscribed to reduced activation in the posterior parietal cortex (PPC) when controlling for group, and they included inferior occipital areas when controlling for targets. The observed behavioral and brain changes are discussed in relation to automatic behavior development. The observed training-related decreases could be associated with increased neural efficiency in specific key regions for task performance. Copyright © 2016 Elsevier Inc. All rights reserved.

An application of artificial intelligence to automatic telescopes

NASA Technical Reports Server (NTRS)

Swanson, Keith; Drummond, Mark; Bresina, John

1992-01-01

Automatic Photoelectric Telescopes (APT's) allow an astronomer to be removed form the telescope site in both time and space. APT's 'execute' an observation program (a set of observation requests) expressed in an ASCII-based language (ATIS) and collect observation results expressed in this same language. The observation program is currently constructed by a Principal Astronomer from the requests of multiple users; the execution is currently controlled by a simple heuristic dispatch scheduler. Research aimed at improving the use of APT's is being carried out by the Entropy Reduction Engine (ERE) project at NASA Ames. The overall goal of the ERE project is the study and construction of systems that integrate planning, scheduling, and control. This paper discusses the application of some ERE technical results to the improvement of both the scheduling and the operation of APT's.

A Newly Identified Role of the Deciduous Forest Floor in the Timing of Green-Up

NASA Astrophysics Data System (ADS)

Lapenis, Andrei G.; Lawrence, Gregory B.; Buyantuev, Alexander; Jiang, Shiguo; Sullivan, Timothy J.; McDonnell, Todd C.; Bailey, Scott

2017-11-01

Plant phenology studies rarely consider controlling factors other than air temperature. We evaluate here the potential significance of physical and chemical properties of soil (edaphic factors) as additional important controls on phenology. More specifically, we investigate causal connections between satellite-observed green-up dates of small forest watersheds and soil properties in the Adirondack Mountains of New York, USA. Contrary to the findings of previous studies, where edaphic controls of spring phenology were found to be marginal, our analyses show that at least three factors manifest themselves as significant controls of seasonal patterns of variation in vegetated land surfaces observed from remote sensing: (1) thickness of the forest floor, (2) concentration of exchangeable soil potassium, and (3) soil acidity. For example, a thick forest floor appears to delay the onset of green-up. Watersheds with elevated concentrations of potassium are associated with early surface greening. We also found that trees growing in strongly acidified watersheds demonstrate delayed green-up dates. Overall, our work demonstrates that, at the scale of small forest watersheds, edaphic factors can explain a significant percentage of the observed spatial variation in land surface phenology that is comparable to the percentage that can be explained by climatic and landscape factors. We conclude that physical and chemical properties of forest soil play important roles in forest ecosystems as modulators of climatic drivers controlling the rate of spring soil warming and the transition of trees out of winter dormancy.