'Real-life' study of imatinib therapy in chronic phase-chronic myeloid leukemia: A novel retrospective observational longitudinal analysis.

PubMed

Merante, Serena; Ferretti, Virginia; Elena, Chiara; Calvello, Celeste; Rocca, Barbara; Zappatore, Rita; Cavigliano, Paola; Orlandi, Ester

2017-01-01

Imatinib is a cornerstone of treatment of chronic myeloid leukemia. It remains unclear whether transient treatment discontinuation or dose changes affect outcome and this approach has not yet been approved for use outside clinical trials. We conducted a retrospective single-institution observational study to evaluate factors affecting response in 'real-life' clinical practice in 138 chronic myeloid leukemia patients in chronic phase treated with imatinib. We used a novel longitudinal data analytical model, with a generalized estimating equation model, to study BCR-ABL variation according to continuous standard dose, change in dose or discontinuation; BCR-ABL transcript levels were recorded. Treatment history was subdivided into time periods for which treatment was given at constant dosage (total 483 time periods). Molecular and cytogenetic complete response was observed after 154 (32%) and 358 (74%) time periods, respectively. After adjusting for length of time period, no association between dose and cytogenetic complete response rate was observed. There was a significantly lower molecular complete response rate after time periods at a high imatinib dosage. This statistical approach can identify individual patient variation in longitudinal data collected over time and suggests that changes in dose or discontinuation of therapy could be considered in patients with appropriate biological characteristics.

Do Indonesian Children's Experiences with Large Currency Units Facilitate Magnitude Estimation of Long Temporal Periods?

NASA Astrophysics Data System (ADS)

Cheek, Kim A.

2017-08-01

Ideas about temporal (and spatial) scale impact students' understanding across science disciplines. Learners have difficulty comprehending the long time periods associated with natural processes because they have no referent for the magnitudes involved. When people have a good "feel" for quantity, they estimate cardinal number magnitude linearly. Magnitude estimation errors can be explained by confusion about the structure of the decimal number system, particularly in terms of how powers of ten are related to one another. Indonesian children regularly use large currency units. This study investigated if they estimate long time periods accurately and if they estimate those time periods the same way they estimate analogous currency units. Thirty-nine children from a private International Baccalaureate school estimated temporal magnitudes up to 10,000,000,000 years in a two-part study. Artifacts children created were compared to theoretical model predictions previously used in number magnitude estimation studies as reported by Landy et al. (Cognitive Science 37:775-799, 2013). Over one third estimated the magnitude of time periods up to 10,000,000,000 years linearly, exceeding what would be expected based upon prior research with children this age who lack daily experience with large quantities. About half treated successive powers of ten as a count sequence instead of multiplicatively related when estimating magnitudes of time periods. Children generally estimated the magnitudes of long time periods and familiar, analogous currency units the same way. Implications for ways to improve the teaching and learning of this crosscutting concept/overarching idea are discussed.

Impact of STROBE statement publication on quality of observational study reporting: interrupted time series versus before-after analysis.

PubMed

Bastuji-Garin, Sylvie; Sbidian, Emilie; Gaudy-Marqueste, Caroline; Ferrat, Emilie; Roujeau, Jean-Claude; Richard, Marie-Aleth; Canoui-Poitrine, Florence

2013-01-01

In uncontrolled before-after studies, CONSORT was shown to improve the reporting of randomised trials. Before-after studies ignore underlying secular trends and may overestimate the impact of interventions. Our aim was to assess the impact of the 2007 STROBE statement publication on the quality of observational study reporting, using both uncontrolled before-after analyses and interrupted time series. For this quasi-experimental study, original articles reporting cohort, case-control, and cross-sectional studies published between 2004 and 2010 in the four dermatological journals having the highest 5-year impact factors (≥ 4) were selected. We compared the proportions of STROBE items (STROBE score) adequately reported in each article during three periods, two pre STROBE period (2004-2005 and 2006-2007) and one post STROBE period (2008-2010). Segmented regression analysis of interrupted time series was also performed. Of the 456 included articles, 187 (41%) reported cohort studies, 166 (36.4%) cross-sectional studies, and 103 (22.6%) case-control studies. The median STROBE score was 57% (range, 18%-98%). Before-after analysis evidenced significant STROBE score increases between the two pre-STROBE periods and between the earliest pre-STROBE period and the post-STROBE period (median score2004-05 48% versus median score2008-10 58%, p<0.001) but not between the immediate pre-STROBE period and the post-STROBE period (median score2006-07 58% versus median score2008-10 58%, p = 0.42). In the pre STROBE period, the six-monthly mean STROBE score increased significantly, by 1.19% per six-month period (absolute increase 95%CI, 0.26% to 2.11%, p = 0.016). By segmented analysis, no significant changes in STROBE score trends occurred (-0.40%; 95%CI, -2.20 to 1.41; p = 0.64) in the post STROBE statement publication. The quality of reports increased over time but was not affected by STROBE. Our findings raise concerns about the relevance of uncontrolled before-after analysis for estimating the impact of guidelines.

Impact of STROBE Statement Publication on Quality of Observational Study Reporting: Interrupted Time Series versus Before-After Analysis

PubMed Central

Bastuji-Garin, Sylvie; Sbidian, Emilie; Gaudy-Marqueste, Caroline; Ferrat, Emilie; Roujeau, Jean-Claude; Richard, Marie-Aleth; Canoui-Poitrine, Florence

2013-01-01

Background In uncontrolled before-after studies, CONSORT was shown to improve the reporting of randomised trials. Before-after studies ignore underlying secular trends and may overestimate the impact of interventions. Our aim was to assess the impact of the 2007 STROBE statement publication on the quality of observational study reporting, using both uncontrolled before-after analyses and interrupted time series. Methods For this quasi-experimental study, original articles reporting cohort, case-control, and cross-sectional studies published between 2004 and 2010 in the four dermatological journals having the highest 5-year impact factors (≥4) were selected. We compared the proportions of STROBE items (STROBE score) adequately reported in each article during three periods, two pre STROBE period (2004–2005 and 2006–2007) and one post STROBE period (2008–2010). Segmented regression analysis of interrupted time series was also performed. Results Of the 456 included articles, 187 (41%) reported cohort studies, 166 (36.4%) cross-sectional studies, and 103 (22.6%) case-control studies. The median STROBE score was 57% (range, 18%–98%). Before-after analysis evidenced significant STROBE score increases between the two pre-STROBE periods and between the earliest pre-STROBE period and the post-STROBE period (median score2004–05 48% versus median score2008–10 58%, p<0.001) but not between the immediate pre-STROBE period and the post-STROBE period (median score2006–07 58% versus median score2008–10 58%, p = 0.42). In the pre STROBE period, the six-monthly mean STROBE score increased significantly, by 1.19% per six-month period (absolute increase 95%CI, 0.26% to 2.11%, p = 0.016). By segmented analysis, no significant changes in STROBE score trends occurred (−0.40%; 95%CI, −2.20 to 1.41; p = 0.64) in the post STROBE statement publication. Interpretation The quality of reports increased over time but was not affected by STROBE. Our findings raise concerns about the relevance of uncontrolled before-after analysis for estimating the impact of guidelines. PMID:23990867

Improving Team Performance and Participation via Computer-mediated Turn Taking and Informational Prompts.

DTIC Science & Technology

1981-03-01

Abstract (continued) that time. A second independent variable studied was the use of informational prompts consisting of periodic computer displays of...resolved by allowing the person to speak first who had spoken least up to that time. A second independent variable studied was the use of...beneficial in a team which interacts repeatedly over an extended period of time. In the study to be presented here, a specially designed electronic

Leveraging Digital Health Technologies and Outpatient Sampling in Clinical Drug Development: A Phase 1 Exploratory Study.

PubMed

Dockendorf, Marissa F; Murthy, Gowri; Bateman, Kevin P; Kothare, Prajakti A; Anderson, Melanie; Xie, Iris; Sachs, Jeff R; Burlage, Rubi; Goldman, Andra; Moyer, Matthew; Shah, Jyoti; Ruba, Rachel; Shipley, Lisa; Harrelson, Jane

2018-06-09

Merck & Co., Inc. (Kenilworth, New Jersey) is investing in approaches to enrich clinical trial data and augment decision-making through utilization of digital health technologies, outpatient sampling, and real-time data access. As part of this strategy, a Phase 1 study was conducted to explore a few technologies of interest. In this fixed-sequence, two-period trial, 16 healthy subjects were administered 50-mg once-daily sitagliptin packaged in a bottle that electronically captured the date and time study medication was dispensed (Period 1) and in a traditional pharmacy bottle (Period 2). Dried blood spot (DBS) samples were collected for sitagliptin concentration analysis on select study days, both in-clinic and at-home, with collection time recorded using an electronic diary in Period 1 and by clinic staff in Period 2. Study results demonstrated the feasibility and subject acceptance of collecting digital adherence data and outpatient DBS samples in clinical trials and highlighted areas for future improvements. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Time effect of erosion by solid particle impingement on ductile materials

NASA Technical Reports Server (NTRS)

Rao, P. V.; Buckley, D. H.

1983-01-01

Erosion and morphological studies of several metals and alloys eroded by normal impingement jets of spherical glass beads and angular crushed-glass erodent particles were conducted. Erosion morphology (the width, depth, and width-depth ratio of the pit) was studied in order to fully investigate the effect of time on erosion rate. The eroded surfaces were studied with a scanning electron microscope, and surface profiles were measured with a profilometer. A large amount of experimental data reported in the literature was also analyzed in order to understand the effect of variables such as the type of device, the erodent particle size and shape, the impact velocity, and the abrasive charge on erosion-rate-versus-time curves. In the present experiments the pit-width-versus-time or pit-depth-versus-time curves were similar to erosion-versus-time curves for glass-bead impingement. The pit-depth-rate-versus-time curves were similar to erosion-rate-versus-time curves for crushed-glass impingement. Analysis of experimental data with two forms of glass resulted in four types of erosion-rate-versus-time curves: (1) incubation, acceleration, and steady-state periods (type I), (2) incubation, acceleration, deceleration, and steady-state periods (type III), (3) incubation, acceleration, peak rate, and deceleration periods (type IV), and (4) incubation, acceleration, steady-state, and deceleration periods (type V).

Attractors for discrete periodic dynamical systems

Treesearch

John E. Franke; James F. Selgrade

2003-01-01

A mathematical framework is introduced to study attractors of discrete, nonautonomous dynamical systems which depend periodically on time. A structure theorem for such attractors is established which says that the attractor of a time-periodic dynamical system is the unin of attractors of appropriate autonomous maps. If the nonautonomous system is a perturbation of an...

Evolution of correlation structure of industrial indices of U.S. equity markets.

PubMed

Buccheri, Giuseppe; Marmi, Stefano; Mantegna, Rosario N

2013-07-01

We investigate the dynamics of correlations present between pairs of industry indices of U.S. stocks traded in U.S. markets by studying correlation-based networks and spectral properties of the correlation matrix. The study is performed by using 49 industry index time series computed by K. French and E. Fama during the time period from July 1969 to December 2011, which spans more than 40 years. We show that the correlation between industry indices presents both a fast and a slow dynamics. The slow dynamics has a time scale longer than 5 years, showing that a different degree of diversification of the investment is possible in different periods of time. Moreover, we also detect a fast dynamics associated with exogenous or endogenous events. The fast time scale we use is a monthly time scale and the evaluation time period is a 3-month time period. By investigating the correlation dynamics monthly, we are able to detect two examples of fast variations in the first and second eigenvalue of the correlation matrix. The first occurs during the dot-com bubble (from March 1999 to April 2001) and the second occurs during the period of highest impact of the subprime crisis (from August 2008 to August 2009).

Evolution of correlation structure of industrial indices of U.S. equity markets

NASA Astrophysics Data System (ADS)

Buccheri, Giuseppe; Marmi, Stefano; Mantegna, Rosario N.

2013-07-01

We investigate the dynamics of correlations present between pairs of industry indices of U.S. stocks traded in U.S. markets by studying correlation-based networks and spectral properties of the correlation matrix. The study is performed by using 49 industry index time series computed by K. French and E. Fama during the time period from July 1969 to December 2011, which spans more than 40 years. We show that the correlation between industry indices presents both a fast and a slow dynamics. The slow dynamics has a time scale longer than 5 years, showing that a different degree of diversification of the investment is possible in different periods of time. Moreover, we also detect a fast dynamics associated with exogenous or endogenous events. The fast time scale we use is a monthly time scale and the evaluation time period is a 3-month time period. By investigating the correlation dynamics monthly, we are able to detect two examples of fast variations in the first and second eigenvalue of the correlation matrix. The first occurs during the dot-com bubble (from March 1999 to April 2001) and the second occurs during the period of highest impact of the subprime crisis (from August 2008 to August 2009).

Periodic fluctuations in correlation-based connectivity density time series: Application to wind speed-monitoring network in Switzerland

NASA Astrophysics Data System (ADS)

Laib, Mohamed; Telesca, Luciano; Kanevski, Mikhail

2018-02-01

In this paper, we study the periodic fluctuations of connectivity density time series of a wind speed-monitoring network in Switzerland. By using the correlogram-based robust periodogram annual periodic oscillations were found in the correlation-based network. The intensity of such annual periodic oscillations is larger for lower correlation thresholds and smaller for higher. The annual periodicity in the connectivity density seems reasonably consistent with the seasonal meteo-climatic cycle.

Prospective Trial of House Staff Time to Response and Intervention in a Surgical Intensive Care Unit: Pager vs. Smartphone.

PubMed

Tatum, James M; White, Terris; Kang, Christopher; Ley, Eric J; Melo, Nicolas; Bloom, Matthew; Alban, Rodrigo F

The objective of the study was to characterize house staff time to response and intervention when notified of a patient care issue by pager vs. smartphone. We hypothesized that smartphones would reduce house staff time to response and intervention. Prospective study of all electronic communications was conducted between nurses and house staff between September 2015 and October 2015. The 4-week study period was randomly divided into two 2-week study periods where all electronic communications between intensive care unit nurses and intensive care unit house staff were exclusively by smartphone or by pager, respectively. Time of communication initiation, time of house staff response, and time from response to clinical intervention for each communication were recorded. Outcomes are time from nurse contact to house staff response and intervention. Single-center surgical intensive care unit of Cedars-Sinai Medical Center in Los Angeles, California, an academic tertiary care and level I trauma center. All electronic communications occurring between nurses and house staff in the study unit during the study period were considered. During the study period, 205 nurse-house staff electronic communications occurred, 100 in the phone group and 105 in the pager group. House staff response to communication time was significantly shorter in the phone group (0.5 [interquartile range = 1.7] vs. 2 [3]min, p < 0.001). Time to house staff intervention after response was also significantly more rapid in the phone group (0.8 [1.7] vs. 1 [2]min, p = 0.003). Dedicated clinical smartphones significantly decrease time to house staff response after electronic nursing communications compared with pagers. Copyright © 2017 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

A comparison of the effect of early insertion of standard latex and silver-impregnated latex foley catheters on urinary tract infections in burn patients.

PubMed

Newton, Terry; Still, Joseph M; Law, Edward

2002-04-01

A retrospective study was designed to compare the incidence of urinary tract infections during two different time periods in burn patients treated with two different types of Foley catheters. In time period 1, latex catheters present on admission were not changed. In time period 2, catheters were replaced on admission with silver alloy-impregnated catheters. In time period 1, the rate of symptomatic urinary tract infections was 7.2 per 1,000 catheter-days. In time period 2, the rate was 4.4 per 1,000 catheter-days. Results, compared using Fisher's exact test, revealed a statistically significant P value of .029. The use of silver-impregnated catheters significantly lowered the rate of urinary tract infection at our burn center.

Increase in carbon accumulation in a boreal peatland following a period of wetter climate and long-term decrease in nitrogen deposition.

PubMed

Utstøl-Klein, Simon; Halvorsen, Rune; Ohlson, Mikael

2015-06-01

Rates of peat growth and carbon (C) accumulation in a Sphagnum-dominated boreal peatland in south-east Norway were compared over two time periods each 17 yr long, that is, an earlier period from 1978 to 1995 and a recent period from 1995 to 2012. Our research was based on 109 peat cores. By using exactly the same study area and sampling protocols to obtain data for the two time periods, we were able to obtain a clear picture of the spatio-temporal patterns of peat accumulation. We show that peat growth and C accumulation were significantly higher in the recent than in the earlier time period. Interestingly, nitrogen (N) deposition was lower in the recent than in the earlier time period, while precipitation increased in the recent time period. Temperatures did not show any consistent trends over the time periods. Although our data do not allow assessment of the relative importance of declining N deposition vs increasing precipitation as drivers of peat accumulation, our results suggest that peatland C sequestration is not significantly inhibited by N pollution at current precipitation and N deposition levels. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Visual impairment due to retinopathy of prematurity (ROP) in New Zealand: a 22-year review.

PubMed

Tan, Zachary; Chong, CheeFoong; Darlow, Brian; Dai, Shuan

2015-06-01

To evaluate retinopathy of prematurity (ROP)-related visual impairment in New Zealand children. 22-year retrospective review of medical records of children with moderate to severe visual impairment registered with the Blind and Low Vision Education Network New Zealand. The cohort was divided into two periods (1991-2004; 2005-2012) for analysis. 232 children with ROP were treated in the study period (109 in period 1, 123 in period 2). 36 children, 63.9% of whom were of male sex, were identified with subsequent significant visual impairment (27 in period 1, 9 in period 2). The incidence of new cases of visual impairment from ROP declined from 271.6 infants/100 000 live very preterm births per annum (period 1) to 146.1 per annum (period 2). Mean gestational age and mean birth weight were comparable between the two study periods. 75% of children with visual impairment from ROP received treatment for their condition (period 1, 74.1%; period 2, 77.8%) and modalities used changed significantly over time. The modal visual outcome overall was Snellen visual acuity <6/18-6/60 (55.6%) (period 1, 51.9%; period 2, 66.7%). The proportion of children with no light perception bilaterally decreased over time (period 1, 3.7%; period 2, 0%). There has been a reduction in the incidence of infants with significant visual impairment from ROP over time in New Zealand, likely due to progress in clinical management of ROP. Our study suggests the current ROP screening criteria of <31 weeks' gestation or <1250 g are of sufficient breadth. 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.

Lean management in academic surgery.

PubMed

Collar, Ryan M; Shuman, Andrew G; Feiner, Sandra; McGonegal, Amy K; Heidel, Natalie; Duck, Mary; McLean, Scott A; Billi, John E; Healy, David W; Bradford, Carol R

2012-06-01

Lean is a management system designed to enhance productivity by eliminating waste. Surgical practice offers many opportunities for improving efficiency. Our objective was to determine whether systematic implementation of lean thinking in an academic otolaryngology operating room improves efficiency and profitability and preserves team morale and educational opportunities. In an 18-month prospective quasi-experimental study, a multidisciplinary task force systematically implemented lean thinking within an otolaryngology operating room of an academic health system. Operating room turnover time and turnaround time were measured during a baseline period; an observer-effect period in which workers were made aware that their efficiency was being measured but before implementing lean changes; and an intervention period after redesign principles had been used. The impact on teamwork, morale, and surgical resident education were measured during the baseline and intervention periods through validated surveys. A profit model was applied to estimate the financial implications of the study. There was no difference between the baseline and observer-effect periods of the study for turnover time (p = 0.98) or turnaround time (p = 0.20). During the intervention period, the mean turnover time and turnaround time were significantly shorter than during the baseline period (29 vs 38 minutes; p < 0.001 and 69 vs 89 minutes; p < 0.001, respectively). The composite morale score suggested improved morale after implementation (p = 0.011). Educational metrics were unchanged before and after implementation. The annual opportunity revenue for the involved operating room is $330,000; when extrapolated throughout the operating rooms, lean thinking could create 6,500 hours of capacity annually. Application of lean management techniques to a single operating room and surgical service improved operating room efficiency and morale, sustained resident education, and can provide considerable financial gains when scaled to an entire academic surgical suite. Copyright © 2012. Published by Elsevier Inc.

The impact of the Vancouver Winter Olympics on population level physical activity and sport participation among Canadian children and adolescents: population based study.

PubMed

Craig, Cora L; Bauman, Adrian E

2014-09-03

There has been much debate about the potential impact of the Olympics. The purpose of this study was to determine if hosting the 2010 Vancouver Olympic Games (OG) encouraged Canadian children to be physically active. Children 5-19 years (n = 19862) were assessed as part of the representative Canadian Physical Activity Levels Among Youth surveillance study between August 2007 and July 2011. Parents were asked if the child participated in organized physical activity or sport. In addition, children wore pedometers for 7 days to objectively provide an estimate of overall physical activity. Mean steps/day and percent participating in organized physical activity or sport were calculated by time period within year for Canada and British Columbia. The odds of participation by time period were estimated by logistic regression, controlling for age and sex. Mean steps were lower during the Olympic period compared with Pre- (607 fewer steps/day 95% CI 263-950 steps/day) and Post-Olympic (1246 fewer steps 95% CI 858-1634 steps) periods for Canada. There was no difference by time period in British Columbia. A similar pattern in mean steps by time period was observed across years, but there were no significant differences in activity within each of these periods between years. The likelihood of participating in organized physical activity or sport by time period within or across years did not differ from baseline (August-November 2007). The 2010 Olympic Games had no measurable impact on objectively measured physical activity or the prevalence of overall sports participation among Canadian children. Much greater cross-Government and long-term efforts are needed to create the conditions for an Olympic legacy effect on physical activity.

47 CFR 54.805 - Zone and study area above benchmark revenues calculated by the Administrator.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Period Residential and Single-Line Business Lines times 12. If negative, the Zone Above Benchmark...) multiplied by all eligible telecommunications carrier zone Base Period Multi-line Business Lines times 12. If... 47 Telecommunication 3 2010-10-01 2010-10-01 false Zone and study area above benchmark revenues...

Outcomes in patients with community-acquired pneumonia admitted to the intensive care unit.

PubMed

Cavallazzi, Rodrigo; Wiemken, Timothy; Arnold, Forest W; Luna, Carlos M; Bordon, Jose; Kelley, Robert; Feldman, Charles; Chalmers, James D; Torres, Antoni; Ramirez, Julio

2015-06-01

Severe community-acquired pneumonia (CAP) portends a serious prognosis. The temporal trend in outcome of severe CAP is not well established. We evaluated the temporal trends in the outcomes of severe CAP. This is a secondary analysis of 800 patients with severe CAP enrolled in the Community-Acquired Pneumonia Organization International Cohort. Severe CAP was defined as CAP requiring admission to the intensive care unit. Only patients admitted to the ICU upon hospital admission were included in this study. We assessed the trend in outcomes of these patients during three time periods: Period I (June 2001 to April 2004), Period II (May 2004 to January 31 2008), and Period III (February 2008 to February 2013). After adjustment for other variables, mortality was higher for patients admitted during Period II compared with Period I (RR: 1.46; 95% CI: 1.002 to 2.14; P value = 0.049), and for Period III compared with Period I (RR: 1.70; 95% CI: 1.15 to 2.50; P value = 0.008). No significant difference in length of stay or time to clinical stability was found among the three periods. The mortality of patients with severe CAP increased over time in our study population. This finding has important health policy implications if confirmed by other studies. Copyright © 2015 Elsevier Ltd. All rights reserved.

Periodic trim solutions with hp-version finite elements in time

NASA Technical Reports Server (NTRS)

Peters, David A.; Hou, Lin-Jun

1990-01-01

Finite elements in time as an alternative strategy for rotorcraft trim problems are studied. The research treats linear flap and linearized flap-lag response both for quasi-trim and trim cases. The connection between Fourier series analysis and hp-finite elements for periodic a problem is also examined. It is proved that Fourier series is a special case of space-time finite elements in which one element is used with a strong displacement formulation. Comparisons are made with respect to accuracy among Fourier analysis, displacement methods, and mixed methods over a variety parameters. The hp trade-off is studied for the periodic trim problem to provide an optimum step size and order of polynomial for a given error criteria. It is found that finite elements in time can outperform Fourier analysis for periodic problems, and for some given error criteria. The mixed method provides better results than does the displacement method.

Outcomes over Time in Patients with Hostile Neck Anatomy Undergoing Endovascular Repair of Abdominal Aortic Aneurysm.

PubMed

Bryce, Yolanda; Kim, Wonho; Katzen, Barry; Benenati, James; Samuels, Shaun

2018-07-01

To assess differences in outcome in an early and later time period in patients with hostile neck anatomy who underwent endovascular aneurysm repair (EVAR). This single-center, institutional review board-approved retrospective study assessed patients who underwent EVAR between 2004 and 2013, divided into 2 time periods: 2004-2008 and 2009-2013. One hundred twenty-five patients had at least 1 hostile neck parameter that met inclusion criteria: 61 of 216 (28%) patients in the early period and 64 of 144 (44%) patients in the late period. Patients in the late group were younger compared to patients in the early group (late group, 74.5 ± 8.8 years vs early group, 77.5 ± 7.5 years; P = .046). No significant differences were observed in hostile neck anatomic factors between the early and late periods. No statistical difference was observed in periprocedural factors or outcome measures, except for abdominal aortic aneurysm (AAA) sac regression in the late period compared to the early period (late period, 73.5% vs early period, 55.7%; P = .038). A statistically significant increase was observed in type 1a endoleaks in patients in the late group with suprarenal fixation compared to patients with infrarenal fixation (suprarenal, 27.0% vs infrarenal, 7.9%; P = .025) and in the overall time studied (suprarenal, 20.3% vs infrarenal, 7.6%; P = .045). Except for AAA sac regression, no changes were observed in periprocedural factors and outcome measures over time in patients with hostile neck who underwent EVAR. Copyright © 2018 SIR. Published by Elsevier Inc. All rights reserved.

Timing of AB And eclipses

NASA Astrophysics Data System (ADS)

Kozyreva, V. S.; Ibrahimov, M. A.; Gaynullina, E. R.; Karimov, R. G.; Hafizov, B. M.; Satovskii, B. L.; Krushevska, V. N.; Kuznyetsova, Yu. G.; Bogomazov, A. I.; Irsmambetova, T. R.; Tutukov, A. V.

2018-01-01

This study aims timing the eclipses of the short period low mass binary star AB And. The times of minima are taken from the literature and from our observations in October 2013 (22 times of minima) and in August 2014 (23 times of minima). We find and discuss an inaccuracy in the determination of the types of minima in the previous investigation by Li et al. (2014). We study the secular evolution of the central binary's orbital period and the possibility of the existence of third and fourth companions in the system.

Detecting a periodic signal in the terrestrial cratering record

NASA Technical Reports Server (NTRS)

Grieve, Richard A. F.; Rupert, James D.; Goodacre, Alan K.; Sharpton, Virgil L.

1988-01-01

A time-series analysis of model periodic data, where the period and phase are known, has been performed in order to investigate whether a significant period can be detected consistently from a mix of random and periodic impacts. Special attention is given to the effect of age uncertainties and random ages in the detection of a periodic signal. An equivalent analysis is performed with observed data on crater ages and compared with the model data, and the effects of the temporal distribution of crater ages on the results from the time-series analysis are studied. Evidence for a consistent 30-m.y. period is found to be weak.

Trends in worker hearing loss by industry sector, 1981-2010.

PubMed

Masterson, Elizabeth A; Deddens, James A; Themann, Christa L; Bertke, Stephen; Calvert, Geoffrey M

2015-04-01

The purpose of this study was to estimate the incidence and prevalence of hearing loss for noise-exposed U.S. workers by industry sector and 5-year time period, covering 30 years. Audiograms for 1.8 million workers from 1981-2010 were examined. Incidence and prevalence were estimated by industry sector and time period. The adjusted risk of incident hearing loss within each time period and industry sector as compared with a reference time period was also estimated. The adjusted risk for incident hearing loss decreased over time when all industry sectors were combined. However, the risk remained high for workers in Healthcare and Social Assistance, and the prevalence was consistently high for Mining and Construction workers. While progress has been made in reducing the risk of incident hearing loss within most industry sectors, additional efforts are needed within Mining, Construction and Healthcare and Social Assistance. © 2015 Wiley Periodicals, Inc.

Early oral feeding after pancreatoduodenectomy enhances recovery without increasing morbidity

PubMed Central

Gerritsen, Arja; Wennink, Roos A W; Besselink, Marc G H; van Santvoort, Hjalmar C; Tseng, Dorine S J; Steenhagen, Elles; Borel Rinkes, Inne H M; Molenaar, I Quintus

2014-01-01

Objective The aim of this study was to evaluate whether a change in the routine feeding strategy applied after pancreatoduodenectomy (PD) from nasojejunal tube (NJT) feeding to early oral feeding improved clinical outcomes. Methods An observational cohort study was performed in 102 consecutive patients undergoing PD. In period 1 (n = 51, historical controls), the routine postoperative feeding strategy was NJT feeding. This was changed to a protocol of early oral feeding with on-demand NJT feeding in period 2 (n = 51, consecutive prospective cohort). The primary outcome was time to resumption of adequate oral intake. Results The baseline characteristics of study subjects in both periods were comparable. In period 1, 98% (n = 50) of patients received NJT feeding, whereas in period 2, 53% (n = 27) of patients did so [for delayed gastric empting (DGE) (n = 20) or preoperative malnutrition (n = 7)]. The time to resumption of adequate oral intake significantly decreased from 12 days in period 1 to 9 days in period 2 (P = 0.015), and the length of hospital stay shortened from 18 days in period 1 to 13 days in period 2 (P = 0.015). Overall, there were no differences in the incidences of complications of Clavien–Dindo Grade III or higher, DGE, pancreatic fistula, postoperative haemorrhage and mortality between the two periods. Conclusions The introduction of an early oral feeding strategy after PD reduced the time to resumption of adequate oral intake and length of hospital stay without negatively impacting postoperative morbidity. PMID:24308458

Differences in night-time and daytime ambulatory blood pressure when diurnal periods are defined by self-report, fixed-times, and actigraphy: Improving the Detection of Hypertension study.

PubMed

Booth, John N; Muntner, Paul; Abdalla, Marwah; Diaz, Keith M; Viera, Anthony J; Reynolds, Kristi; Schwartz, Joseph E; Shimbo, Daichi

2016-02-01

To determine whether defining diurnal periods by self-report, fixed-time, or actigraphy produce different estimates of night-time and daytime ambulatory blood pressure (ABP). Over a median of 28 days, 330 participants completed two 24-h ABP and actigraphy monitoring periods with sleep diaries. Fixed night-time and daytime periods were defined as 0000-0600 h and 1000-2000 h, respectively. Using the first ABP period, within-individual differences for mean night-time and daytime ABP and kappa statistics for night-time and daytime hypertension (systolic/diastolic ABP≥120/70 mmHg and ≥135/85 mmHg, respectively) were estimated comparing self-report, fixed-time, or actigraphy for defining diurnal periods. Reproducibility of ABP was also estimated. Within-individual mean differences in night-time systolic ABP were small, suggesting little bias, when comparing the three approaches used to define diurnal periods. The distribution of differences, represented by 95% confidence intervals (CI), in night-time systolic and diastolic ABP and daytime systolic and diastolic ABP was narrowest for self-report versus actigraphy. For example, mean differences (95% CI) in night-time systolic ABP for self-report versus fixed-time was -0.53 (-6.61, +5.56) mmHg, self-report versus actigraphy was 0.91 (-3.61, +5.43) mmHg, and fixed-time versus actigraphy was 1.43 (-5.59, +8.46) mmHg. Agreement for night-time and daytime hypertension was highest for self-report versus actigraphy: kappa statistic (95% CI) = 0.91 (0.86,0.96) and 1.00 (0.98,1.00), respectively. The reproducibility of mean ABP and hypertension categories was similar using each approach. Given the high agreement with actigraphy, these data support using self-report to define diurnal periods on ABP monitoring. Further, the use of fixed-time periods may be a reasonable alternative approach.

From Crisis to Renewal: One School's Journey

ERIC Educational Resources Information Center

Skelcher, Ann M.

2011-01-01

This case study describes a time period of 6 years in the history of a school, a period marked by crisis recovery and organizational response to a mandated large-scale reform. Despite its challenges, when speaking of this period a number of the staff reflected on it as a kind of magical moment in time. Twenty years later, I began to wonder what…

Forum Page Letters in the "Straits Times" of Singapore during Relatively Free and Restricted Press Periods.

ERIC Educational Resources Information Center

Ramaprasad, Jyotika; Ong, James

In order to identify the scope or limits of the practice of development journalism, a study examined the content of the Forum page in the "Straits Times" of Singapore during relatively free (1979-1980) and restricted (1986-1987) press periods. The study had two major objectives: (1) to study the nature of the Forum page (a readers'…

Modelling exploration of non-stationary hydrological system

NASA Astrophysics Data System (ADS)

Kim, Kue Bum; Kwon, Hyun-Han; Han, Dawei

2015-04-01

Traditional hydrological modelling assumes that the catchment does not change with time (i.e., stationary conditions) which means the model calibrated for the historical period is valid for the future period. However, in reality, due to change of climate and catchment conditions this stationarity assumption may not be valid in the future. It is a challenge to make the hydrological model adaptive to the future climate and catchment conditions that are not observable at the present time. In this study a lumped conceptual rainfall-runoff model called IHACRES was applied to a catchment in southwest England. Long observation data from 1961 to 2008 were used and seasonal calibration (in this study only summer period is further explored because it is more sensitive to climate and land cover change than the other three seasons) has been done since there are significant seasonal rainfall patterns. We expect that the model performance can be improved by calibrating the model based on individual seasons. The data is split into calibration and validation periods with the intention of using the validation period to represent the future unobserved situations. The success of the non-stationary model will depend not only on good performance during the calibration period but also the validation period. Initially, the calibration is based on changing the model parameters with time. Methodology is proposed to adapt the parameters using the step forward and backward selection schemes. However, in the validation both the forward and backward multiple parameter changing models failed. One problem is that the regression with time is not reliable since the trend may not be in a monotonic linear relationship with time. The second issue is that changing multiple parameters makes the selection process very complex which is time consuming and not effective in the validation period. As a result, two new concepts are explored. First, only one parameter is selected for adjustment while the other parameters are set as constant. Secondly, regression is made against climate condition instead of against time. It has been found that such a new approach is very effective and this non-stationary model worked very well both in the calibration and validation period. Although the catchment is specific in southwest England and the data are for only the summer period, the methodology proposed in this study is general and applicable to other catchments. We hope this study will stimulate the hydrological community to explore a variety of sites so that valuable experiences and knowledge could be gained to improve our understanding of such a complex modelling issue in climate change impact assessment.

A hybrid-domain approach for modeling climate data time series

NASA Astrophysics Data System (ADS)

Wen, Qiuzi H.; Wang, Xiaolan L.; Wong, Augustine

2011-09-01

In order to model climate data time series that often contain periodic variations, trends, and sudden changes in mean (mean shifts, mostly artificial), this study proposes a hybrid-domain (HD) algorithm, which incorporates a time domain test and a newly developed frequency domain test through an iterative procedure that is analogue to the well known backfitting algorithm. A two-phase competition procedure is developed to address the confounding issue between modeling periodic variations and mean shifts. A variety of distinctive features of climate data time series, including trends, periodic variations, mean shifts, and a dependent noise structure, can be modeled in tandem using the HD algorithm. This is particularly important for homogenization of climate data from a low density observing network in which reference series are not available to help preserve climatic trends and long-term periodic variations, preventing them from being mistaken as artificial shifts. The HD algorithm is also powerful in estimating trend and periodicity in a homogeneous data time series (i.e., in the absence of any mean shift). The performance of the HD algorithm (in terms of false alarm rate and hit rate in detecting shifts/cycles, and estimation accuracy) is assessed via a simulation study. Its power is further illustrated through its application to a few climate data time series.

The Impact of a Rigorous Multiple Work Shift Schedule and Day Versus Night Shift Work on Reaction Time and Balance Performance in Female Nurses: A Repeated Measures Study.

PubMed

Thompson, Brennan J; Stock, Matt S; Banuelas, Victoria K; Akalonu, Chibuzo C

2016-07-01

The aim of this study was to determine the impact of a demanding work schedule involving long, cumulative work shifts on response time and balance-related performance outcomes and to evaluate the prevalence of musculoskeletal disorders between day and night shift working nurses. A questionnaire was used to identify the prevalence of past (12-month) and current (7-day) musculoskeletal disorders. Nurses worked three 12-hour work shifts in a 4-day period. Reaction time and balance tests were conducted before and after the work period. The work period induced impairments for reaction time, errors on reaction time tasks, and balance performance, independent of shift type. Musculoskeletal symptom prevalence was high in workers of both work shifts. Compressed work shifts caused performance-based fatigue in nurses. Reaction time and balance tests may be sensitive fatigue identification markers in nurses.

Postfledging nest dependence period for bald eagles in Florida

USGS Publications Warehouse

Wood, P.B.; Collopy, Michael W.; Sekerak, C.M.

1998-01-01

We studied the postfledging dependency period in bald eagles (Haliaeetus leucocephalus), a little studied but important period in the life cycle of avian species. Bald eagles in Florida had a postfledging dependency period of 4-11 weeks (15-22 weeks old). The length of the dependency period did not vary by year of study, sex, number of fledgings, timing of fledging, or hatch order (P > 0.05). Mean distance fledglings ranged from the nest increased with age, but they were observed in the nest or nest tree throughout the postfledging dependency period. Distance from the nest did not vary by sex, number of fledglings, or timing of fledging (P > 0.05). Over 80% of the fledgling observations were within 229 m of the nest. The boundary of the primary protection zone specified in the bald eagle habitat management guidelines for the southeastern United States is 229 m. Restrictions on human disturbance around nest sites should remain in place during the postfledging dependency period because of the close association of fledglings with the nest site. Restrictions also should be flexible because of the varying length of the dependency period.

Timing and Variability of Postpartum Sleep in Relation to Daytime Performance

PubMed Central

McBean, Amanda L.; Montgomery-Downs, Hawley E.

2013-01-01

Postpartum women have highly disturbed sleep, also known as sleep fragmentation. Fragmentation extends their total sleep period, also disrupting sleep timing. A stable and earlier sleep period among non-postpartum populations are related to better performance, physical health, and mental health. However, sleep timing has not been examined among postpartum women who are also vulnerable to daytime impairment. The study objective was to examine how the timing and regularity of sleep during the early postpartum period are related to daytime functioning across postpartum weeks 2-13. In this field-based study, 71 primiparous women wore an actigraph, a small wrist-worn device that monitors sleep and sleep timing, for the 12-week study period. Mothers self-administered a 5-minute psychomotor vigilance test (PVT) each morning to evaluate the number of >500ms response lapses. They also completed a Morningness-Eveningness scale at the beginning of the study to identify chronotype. After controlling for maternal age, earlier sleep timing was associated with significantly fewer PVT lapses at postpartum weeks 9,12; a more stable sleep midpoint was associated with significantly fewer PVT lapses at postpartum weeks 2,5-13. Earlier sleep midpoints were related to more stable sleep midpoints at postpartum week 2 and a morning-type chronotype. An earlier sleep midpoint was also associated with a reduced slope of worsening PVT lapses across weeks. Across the first 12 postpartum weeks, women with earlier or more stable sleep periods had less daytime impairment than women with later or more variable sleep midpoints. Postpartum women with earlier sleep midpoints also showed less severe decrements in performance across time, which has been attributed to cumulative impacts of sleep disturbance. These data suggest the sleep period, in addition to sleep duration and fragmentation, should be more closely examined, particularly among vulnerable women, as it may affect the neurobehavioral performance of new mothers. PMID:24041725

Detection of Diurnal Variation of Tomato Transcriptome through the Molecular Timetable Method in a Sunlight-Type Plant Factory.

PubMed

Higashi, Takanobu; Tanigaki, Yusuke; Takayama, Kotaro; Nagano, Atsushi J; Honjo, Mie N; Fukuda, Hirokazu

2016-01-01

The timing of measurement during plant growth is important because many genes are expressed periodically and orchestrate physiological events. Their periodicity is generated by environmental fluctuations as external factors and the circadian clock as the internal factor. The circadian clock orchestrates physiological events such as photosynthesis or flowering and it enables enhanced growth and herbivory resistance. These characteristics have possible applications for agriculture. In this study, we demonstrated the diurnal variation of the transcriptome in tomato (Solanum lycopersicum) leaves through molecular timetable method in a sunlight-type plant factory. Molecular timetable methods have been developed to detect periodic genes and estimate individual internal body time from these expression profiles in mammals. We sampled tomato leaves every 2 h for 2 days and acquired time-course transcriptome data by RNA-Seq. Many genes were expressed periodically and these expressions were stable across the 1st and 2nd days of measurement. We selected 143 time-indicating genes whose expression indicated periodically, and estimated internal time in the plant from these expression profiles. The estimated internal time was generally the same as the external environment time; however, there was a difference of more than 1 h between the two for some sampling points. Furthermore, the stress-responsive genes also showed weakly periodic expression, implying that they were usually expressed periodically, regulated by light-dark cycles as an external factor or the circadian clock as the internal factor, and could be particularly expressed when the plant experiences some specific stress under agricultural situations. This study suggests that circadian clock mediate the optimization for fluctuating environments in the field and it has possibilities to enhance resistibility to stress and floral induction by controlling circadian clock through light supplement and temperature control.

Detection of Diurnal Variation of Tomato Transcriptome through the Molecular Timetable Method in a Sunlight-Type Plant Factory

PubMed Central

Higashi, Takanobu; Tanigaki, Yusuke; Takayama, Kotaro; Nagano, Atsushi J.; Honjo, Mie N.; Fukuda, Hirokazu

2016-01-01

The timing of measurement during plant growth is important because many genes are expressed periodically and orchestrate physiological events. Their periodicity is generated by environmental fluctuations as external factors and the circadian clock as the internal factor. The circadian clock orchestrates physiological events such as photosynthesis or flowering and it enables enhanced growth and herbivory resistance. These characteristics have possible applications for agriculture. In this study, we demonstrated the diurnal variation of the transcriptome in tomato (Solanum lycopersicum) leaves through molecular timetable method in a sunlight-type plant factory. Molecular timetable methods have been developed to detect periodic genes and estimate individual internal body time from these expression profiles in mammals. We sampled tomato leaves every 2 h for 2 days and acquired time-course transcriptome data by RNA-Seq. Many genes were expressed periodically and these expressions were stable across the 1st and 2nd days of measurement. We selected 143 time-indicating genes whose expression indicated periodically, and estimated internal time in the plant from these expression profiles. The estimated internal time was generally the same as the external environment time; however, there was a difference of more than 1 h between the two for some sampling points. Furthermore, the stress-responsive genes also showed weakly periodic expression, implying that they were usually expressed periodically, regulated by light–dark cycles as an external factor or the circadian clock as the internal factor, and could be particularly expressed when the plant experiences some specific stress under agricultural situations. This study suggests that circadian clock mediate the optimization for fluctuating environments in the field and it has possibilities to enhance resistibility to stress and floral induction by controlling circadian clock through light supplement and temperature control. PMID:26904059

'In the course of time': a PET study of the cerebral substrates of autobiographical amnesia in Alzheimer's disease.

PubMed

Eustache, Francis; Piolino, Pascale; Giffard, Bénédicte; Viader, Fausto; De La Sayette, Vincent; Baron, Jean-Claude; Desgranges, Béatrice

2004-07-01

Neuroimaging studies in healthy subjects have yielded controversial results about the neural substrates of autobiographical memory. Moreover, the neural networks responsible for autobiographical amnesia remain poorly understood. Since autobiographical memory is frequently altered in Alzheimer's disease (AD), we used this degenerative disorder as a model and applied a correlative approach between resting cerebral glucose utilization (CMRGlc) and temporally graded memory scores to identify the cerebral structures whose synaptic dysfunction subserves the impairment in autobiographical memory. To this end, we studied a group of 17 AD patients with mild to moderate dementia in whom autobiographical memory was assessed using a specially designed task from three broad time periods [the previous 5 years (period A); middle age (period B); and teenage and childhood (period C)], and measures of resting CMRGlc were obtained with PET. The patients performed less well than a control group for all three time periods and showed the expected temporal gradient, with the most remote period being best preserved (Ribot's gradient). Qualitative analysis showed that remote memories concerned generic (i.e. semantic) rather than specific (i.e. episodic) events. We found a significant positive correlation between autobiographical scores and the metabolism of the right hippocampus (extending to the lingual gyrus), restricted to period A. In addition, period A scores were significantly correlated with the right middle and inferior frontal gyri and the right middle temporal gyrus. Period B scores correlated chiefly with the prefrontal cortex bilaterally (bilateral superior, bilateral middle and right inferior gyri). Metabolic correlations with period C scores were restricted to the left middle frontal gyrus. These findings show striking differences in metabolic correlations with the autobiographical time period, in agreement with prevalent theories of normal functioning of human memory. Thus, in accordance with theories of long-term memory consolidation, we find the expected implication of the hippocampal region in the recall of recent memories, and a disengagement of this structure when the retention interval is beyond 5 years. Moreover, according to the hemispheric encoding/retrieval asymmetry model based on activation studies in healthy subjects, the fact that recent memories preferentially involved the right prefrontal cortex whereas remote memories involved the left prefrontal cortex supports the notion of semanticization of memories with time interval, such that preserved remote memories in AD have a predominantly semantic character. Copyright 2004 Guarantors of Brain

Practical considerations for estimating clinical trial accrual periods: application to a multi-center effectiveness study

PubMed Central

Carter, Rickey E; Sonne, Susan C; Brady, Kathleen T

2005-01-01

Background Adequate participant recruitment is vital to the conduct of a clinical trial. Projected recruitment rates are often over-estimated, and the time to recruit the target population (accrual period) is often under-estimated. Methods This report illustrates three approaches to estimating the accrual period and applies the methods to a multi-center, randomized, placebo controlled trial undergoing development. Results Incorporating known sources of accrual variation can yield a more justified estimate of the accrual period. Simulation studies can be incorporated into a clinical trial's planning phase to provide estimates for key accrual summaries including the mean and standard deviation of the accrual period. Conclusion The accrual period of a clinical trial should be carefully considered, and the allocation of sufficient time for participant recruitment is a fundamental aspect of planning a clinical trial. PMID:15796782

Fecal blood loss caused by two differently microencapsulated acetylsalicylic acid preparations in patients with rheumatoid arthritis. A prospective crossover study.

PubMed

Dirksen, A; Rasmussen, S N; Manthorpe, R

1982-01-01

In an investigator-blind crossover study, fecal blood loss determined by 51Cr-labelled red cells was measured in 17 male patients with rheumatoid arthritis and one with anchylosing spondylitis. In two periods, each of one week's duration and separated by a 3-week wash-out period, the patients received microencapsulated acetylsalicylic acid (ASA) 3 g daily--either iwht time-dependent (Acetard) or with pH-depeendent release (Reumyl). With the exception of one patient, who suffered clinically significant bleeding, both preparations produced only moderate bleeding. The bleeding provoked by ASA with pH-dependent release (median blood loss in ml/day: first period 1.6; last period 2.6) was less than with time-dependent release (first period 1.8; last period 3.5).

Identification of periods of clear sky irradiance in time series of GHI measurements

DOE PAGES

Reno, Matthew J.; Hansen, Clifford W.

2016-01-18

In this study, we present a simple algorithm for identifying periods of time with broadband global horizontal irradiance (GHI) similar to that occurring during clear sky conditions from a time series of GHI measurements. Other available methods to identify these periods do so by identifying periods with clear sky conditions using additional measurements, such as direct or diffuse irradiance. Our algorithm compares characteristics of the time series of measured GHI with the output of a clear sky model without requiring additional measurements. We validate our algorithm using data from several locations by comparing our results with those obtained from amore » clear sky detection algorithm, and with satellite and ground-based sky imagery.« less

Identification of periods of clear sky irradiance in time series of GHI measurements

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

Reno, Matthew J.; Hansen, Clifford W.

In this study, we present a simple algorithm for identifying periods of time with broadband global horizontal irradiance (GHI) similar to that occurring during clear sky conditions from a time series of GHI measurements. Other available methods to identify these periods do so by identifying periods with clear sky conditions using additional measurements, such as direct or diffuse irradiance. Our algorithm compares characteristics of the time series of measured GHI with the output of a clear sky model without requiring additional measurements. We validate our algorithm using data from several locations by comparing our results with those obtained from amore » clear sky detection algorithm, and with satellite and ground-based sky imagery.« less

Socioeconomic inequalities in suicide mortality before and after the economic recession in Spain.

PubMed

Borrell, Carme; Marí-Dell'Olmo, Marc; Gotsens, Mercè; Calvo, Montse; Rodríguez-Sanz, Maica; Bartoll, Xavier; Esnaola, Santiago

2017-10-04

An increase in suicide mortality is often observed in economic recessions. The objective of this study was to analyse trends in socioeconomic inequalities in suicide mortality before and during the economic recession in two geographical settings in Spain. This study analyses inequalities in mortality according to educational level during 3 different time periods based on individual data from the Basque Country and Barcelona city. We analysed suicide mortality data for all residents over 25 years of age from 2001 to 2012. Two periods before the crisis (2001-2004 and 2005-2008) and another during the crisis (2009-2012) were studied. We performed independent analyses for sex, age group, and for the two geographical settings. We fit Poisson regression models to study the relationship between educational level and mortality, and calculated the relative index of inequality (RII) and the slope index of inequality (SII) as comparative measures. For men in the Basque Country, all RII values for the three time periods were similar and almost all were greater than 2; in Barcelona the RII values were generally lower. The SII values for Barcelona tended to decrease over time, whereas in the Basque Country they showed a U-shaped pattern. Among women aged 25-44 years we found an association between educational level and suicide mortality during the first time period; however, we found no clear association for other age groups or time periods. This study within two geographical settings in Spain shows that trends in inequalities in suicide mortality according to educational level remained stable among men before and during the economic recession.

Association of intrinsic circadian period with morningness-eveningness, usual wake time, and circadian phase

NASA Technical Reports Server (NTRS)

Duffy, J. F.; Rimmer, D. W.; Czeisler, C. A.

2001-01-01

The biological basis of preferences for morning or evening activity patterns ("early birds" and "night owls") has been hypothesized but has remained elusive. The authors reported that, compared with evening types, the circadian pacemaker of morning types was entrained to an earlier hour with respect to both clock time and wake time. The present study explores a chronobiological mechanism by which the biological clock of morning types may be set to an earlier hour. Intrinsic period, a fundamental property of the circadian system, was measured in a month-long inpatient study. A subset of participants also had their circadian phase assessed. Participants completed a morningness-eveningness questionnaire before study. Circadian period was correlated with morningness-eveningness, circadian phase, and wake time, demonstrating that a fundamental property of the circadian pacemaker is correlated with the behavioral trait of morningness-eveningness.

CONDOM USE AT LAST SEX AS A PROXY FOR OTHER MEASURES OF CONDOM USE: IS IT GOOD ENOUGH?

PubMed Central

Younge, Sinead N.; Salazar, Laura F.; Crosby, Richard F.; DiClemente, Richard J.; Wingood, Gina M.; Rose, Eve

2009-01-01

Condom use at last sex is a widely used indicator in sexual behavior research; however, there is little empirical research validating this indicator. This study examined whether a single-event recall period (the last time coitus occurred) was consistent with longer recall periods (14 days and 60 days) for a sample of African American adolescent females (N = 566). The findings from this study demonstrate that condom use at last coitus is a valid proxy for condom use behaviors spanning longer time periods. PMID:19149154

The Schwabe and Gleissberg Periods in the Wolf Sunspot Numbers and the Group Sunspot Numbers

NASA Astrophysics Data System (ADS)

Li, K. J.; Gao, P. X.; Su, T. W.

2005-06-01

Three wavelet functions: the Morlet wavelet, the Paul wavelet, and the DOG wavelet have been respectively performed on both the monthly Wolf sunspot numbers (Rz) from January 1749 to May 2004 and the monthly group sunspot numbers (Rg) from June 1795 to December 1995 to study the evolution of the Gleissberg and Schwabe periods of solar activity. The main results obtained are (1) the two most obvious periods in both the Rz and Rg are the Schwabe and Gleissberg periods. The Schwabe period oscillated during the second half of the eighteenth century and was steady from the 1850s onward. No obvious drifting trend of the Schwabe period exists. (2) The Gleissberg period obviously drifts to longer periods the whole consideration time, and the drifting speed of the Gleissberg period is larger for Rz than for Rg. (3) Although the Schwabe-period values for Rz and Rg are about 10.7 years, the value for Rz seems slightly larger than that for Rg. The Schwabe period of Rz is highly significant after the 1820s, and the Schwabe period of Rg is highly significant over almost the whole consideration time except for about 20 years around the 1800s. The evolution of the Schwabe period for both Rz and Rg in time is similar to each other. (4) The Gleissberg period in Rz and Rg is highly significant during the whole consideration time, but this result is unreliable at the two ends of each of the time series of the data. The evolution of the Gleissberg period in Rz is similar to that in Rg.

Decreasing assault occurrence on a psychogeriatric ward: an agitation management model.

PubMed

Savage, Troy; Crawford, Ian; Nashed, Yousery

2004-05-01

An agitation management model providing staff education, quantitative assessment of agitation, and emphasized psychosocial interventions was introduced on a geriatric psychiatry ward for male patients. A within-subjects comparison was made of Cohen-Mansfield Agitation Inventory (CMAI) scores and frequency of committing assault under pre- and post-intervention conditions. Among participants (N = 8) who finished the 72-week study, CMAI scores did not differ significantly under either of the study conditions (p > .05, two-tailed t test). Twenty-nine assaults occurred during the pre-intervention time period and six assaults occurred during the post-intervention time period. According to analysis with the Wilcoxon signed ranks test, the distribution of assaults differed significantly between the two time periods (p < .05, two-tailed). Among individuals who were excluded from the intervention because of lack of consent, assaults increased over the same two time periods. Psychosocial interventions intended to reduce agitation among elderly men with dementia may not necessarily serve to decrease agitation, but may serve to decrease assault occurrence.

[Blood pressure variability and left ventricular hypertrophy in arterial hypertension].

PubMed

Amodeo, C; Martins, S M; Silva Júnior, O; Barros, L M; Batlouni, M; Sousa, J E

1993-05-01

To evaluate the left ventricular hypertrophy correlation with blood pressure variability during day and night time as well as throughout the 24h period. Fifteen patients with mild to moderate essential hypertension underwent to bi-dimensional echocardiographic study and to 24h ambulatory blood pressure monitorization. Left ventricular mass was calculated according to previous validated formulas. The standard deviation of the mean blood pressures during day-time, night-time and 24h period was taken as blood pressure variability indices. The mean age of the group was 42 years old; 9 patients were male and all were white. This study showed that only the systolic and diastolic blood pressure variability during the 24h period correlated significantly with left ventricular mass, (r = 0.53 and p < 0.05; r = 0.58 and p < 0.05 respectively). There was no significant correlation of the day-time and night-time pressures variability with left ventricular mass. The systolic and diastolic blood pressure variability during the 24h period may be one of the many determinants of left ventricular hypertrophy in patients with mild to moderate hypertension.

Period variation studies of six contact binaries in M4

NASA Astrophysics Data System (ADS)

Rukmini, Jagirdar; Shanti Priya, Devarapalli

2018-04-01

We present the first period study of six contact binaries in the closest globular cluster M4 the data collected from June 1995‑June 2009 and Oct 2012‑Sept 2013. New times of minima are determined for all the six variables and eclipse timing (O-C) diagrams along with the quadratic fit are presented. For all the variables, the study of (O-C) variations reveals changes in the periods. In addition, the fundamental parameters for four of the contact binaries obtained using the Wilson-Devinney code (v2003) are presented. Planned observations of these binaries using the 3.6-m Devasthal Optical Telescope (DOT) and the 4-m International Liquid Mirror Telescope (ILMT) operated by the Aryabhatta Research Institute of Observational Sciences (ARIES; Nainital) can throw light on their evolutionary status from long term period variation studies.

Effects of Inhalation Aromatherapy on Symptoms of Sleep Disturbance in the Elderly with Dementia

PubMed Central

Watanuki, Emiko

2017-01-01

This study investigated the effects of inhalation aromatherapy on sleep disturbance in elderly individuals with dementia. In 19 subjects, normal sleep was observed for a 20-day control period, inhalation aromatherapy was then applied for a 20-day intervention period, and the control and intervention periods were compared. During the intervention period, essential oils were placed nightly on towels around the subjects' pillows. The measured sleep conditions were sleep latency, total sleep time, sleep efficacy, duration of the longest sustained sleep period, wake time after sleep onset, early morning awakening, total daytime sleep, and the Neuropsychiatric Inventory. Total sleep time was significantly longer in the intervention period than in the control period (p < 0.05). The duration of the longest sustained sleep period was significantly longer in the intervention period than in the control period (p < 0.05). Early morning awakening in the intervention period was significantly less compared to that in the control period (p < 0.05). Total daytime sleep could not be adequately measured and was omitted from the analysis. No significant differences in other sleep conditions were observed. These results indicated positive effects of inhalation aromatherapy on symptoms of sleep disturbance in elderly individuals with dementia. PMID:28400839

Statistical Analysis of Periodic Oscillations in LASCO Coronal Mass Ejection Speeds

NASA Technical Reports Server (NTRS)

Michalek, G.; Shanmugaraju, A.; Gopalswamy, N.; Yashiro, S.; Akiyama, S.

2016-01-01

A large set of coronal mass ejections (CMEs, 3463) has been selected to study their periodic oscillations in speed in the Solar and Heliospheric Observatory (SOHO) missions Large Angle and Spectrometric Coronagraph (LASCO) field of view. These events, reported in the SOHOLASCO catalog in the period of time 19962004, were selected based on having at least 11 height-time measurements. This selection criterion allows us to construct at least ten-point speed distance profiles and evaluate kinematic properties of CMEs with a reasonable accuracy. To identify quasi-periodic oscillations in the speed of the CMEs a sinusoidal function was fitted to speed distance profiles and the speed time profiles. Of the considered events 22 revealed periodic velocity fluctuations. These speed oscillations have on average amplitude equal to 87 kms(exp -1) and period 7.8R /241 min (in distance-time). The study shows that speed oscillations are a common phenomenon associated with CME propagation implying that all the CMEs have a similar magnetic flux-rope structure. The nature of oscillations can be explained in terms of magnetohydrodynamic (MHD) waves excited during the eruption process. More accurate detection of these modes could, in the future, enable us to characterize magnetic structures in space (space seismology).

First-time fathers' postnatal experiences and support needs: A descriptive qualitative study.

PubMed

Shorey, Shefaly; Dennis, Cindy-Lee; Bridge, Shiho; Chong, Yap Seng; Holroyd, Eleanor; He, Hong-Gu

2017-12-01

To explore first-time fathers' postnatal experiences and support needs in the early postpartum period. The postnatal period is a stressful transition period for new fathers. It is imperative to understand their needs and experiences to provide appropriate support for them. The majority of previous studies were based in Western countries and explored fathers' needs during pregnancy and childbirth, with few studies conducted in the postnatal period. In Singapore, a multiracial society with differing paternal cultural values from its Western counterparts, there is considerable need to examine the experiences and needs of first-time fathers. A descriptive qualitative design was used. Data were collected from November 2015-January 2016. Fifteen first-time fathers were recruited from two postnatal wards of a public hospital, using a purposive sampling method. A semi-structured interview guide was used to conduct face-to-face interviews. A thematic analysis was conducted and ethics approval was sought for this study. Four overarching themes and seventeen subthemes were generated. The four overarching themes were: (1) No sense of reality to sense of responsibility; (2) Unprepared and challenged; (3) Support: needs, sources, experience and attitude; and (4) Future help for fathers. Fathers undergo a transition phase where they have unmet support needs during the early postnatal period. Understanding and addressing these needs may facilitate smooth transition to fatherhood. This study's findings can be used to involve fathers and design future supportive educational programs to promote positive parenting experiences and family dynamics. © 2017 John Wiley & Sons Ltd.

Impact of a direct-to-consumer information campaign on prescription patterns for overactive bladder.

PubMed

Zaitsu, Masayoshi; Yoo, Byung-Kwang; Tomio, Jun; Nakamura, Fumiaki; Toyokawa, Satoshi; Kobayashi, Yasuki

2018-05-03

Direct-to-consumer information (DTCI) campaign is a new medium to inform and empower patients in their decision-making without directly promoting specific drugs. However, little is known about the impact of DTCI campaigns, expanding rapidly in developed countries, on changes in prescription patterns. We sought to determine whether a DTCI campaign on overactive bladder increases the prescription rate for overactive bladder treatment drugs. We performed a 3-year retrospective cohort study of 1332 participants who were diagnosed overactive bladder but not prescribed treatment drugs prior to the examined DTCI campaign (exposure), using the health insurance claims dataset of the Japan Medical Data Center (November 19, 2010 to November 18, 2013). The DTCI campaign for overactive bladder included television, Internet, and print advertising (November 19, 2011 to December 22, 2011). We divided the study period into Pre-Campaign Year (2010-2011), Year 1 (2011-2012), and Year 2 (2012-2013). Each year began on November 19 and included Period 1 (weeks 1-5) through Period 10 (weeks 46-50). The main outcome was first-time prescription of the treatment drug for each patient, measured by 5-week periods. Using Period 10 in the Pre-Campaign Year as the referent period, we applied the Cox proportional hazard model for each period. Additionally, we performed the interrupted time series analysis (ITSA) for the first-time prescription rate per 5-week period. Following the DTCI campaign, patients were about seven times more likely to receive a first prescription of a treatment drug during Period 4 in Year 1 (hazard ratio 7.09; 95% CI, 2.11-23.8; p-value<.01) compared with the reference period. Similar increases were also observed for subsequent Periods 5 and 6 in Year 1. The ITSA confirmed the DTCI campaign impact on the level of prescription rate (one-time increase in the regression-intercept) that increased by 1128.1 [per standardized 100,000 persons] (p < .05) during Period 4 in Year 1. The examined DTCI campaign appeared to increase the prescription rate among patients with overactive bladder for 15 weeks with a 15-week delay. Clinical outcomes of the patients with targeted diseases need to be monitored after DTCI campaigns by a future study.

Method and computer program product for maintenance and modernization backlogging

DOEpatents

Mattimore, Bernard G; Reynolds, Paul E; Farrell, Jill M

2013-02-19

According to one embodiment, a computer program product for determining future facility conditions includes a computer readable medium having computer readable program code stored therein. The computer readable program code includes computer readable program code for calculating a time period specific maintenance cost, for calculating a time period specific modernization factor, and for calculating a time period specific backlog factor. Future facility conditions equal the time period specific maintenance cost plus the time period specific modernization factor plus the time period specific backlog factor. In another embodiment, a computer-implemented method for calculating future facility conditions includes calculating a time period specific maintenance cost, calculating a time period specific modernization factor, and calculating a time period specific backlog factor. Future facility conditions equal the time period specific maintenance cost plus the time period specific modernization factor plus the time period specific backlog factor. Other embodiments are also presented.

78 FR 55312 - Self-Regulatory Organizations; NYSE Arca, Inc.; Notice of Filing of a Proposed Rule Change...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-10

... proposing Rule change. \\5\\ Study period was January through October, 2012. The time frame was chosen to... extended period of time because of LEAP series. For instance, an issue that went bankrupt in the Fall of... times since.\\3\\ \\3\\ Exchange Act Release No. 55156 (January 23, 2007) 72 FR 4759 (February 1, 2007...

Ambient air metallic pollutant study at HAF areas during 2013-2014

NASA Astrophysics Data System (ADS)

Fang, Guor-Cheng; Kuo, Yu-Chen; Zhuang, Yuan-Jie

2015-05-01

This study characterized diurnal variations of the total suspended particulate (TSP) concentrations, dry deposition flux and dry deposition velocity of metallic elements at Taichung Harbor (Harbor), Gong Ming Junior High School (Airport) and Sha lu Farmland (Farmland) sampling sites in central Taiwan between August, 2013 and July, 2014 in this study. The result indicated that: 1) the ambient air particulate concentrations, dry depositions were displayed as Harbor > Farmland > Airport during the day time sampling period. However, dry deposition velocities were shown as Airport > Harbor > Farmland for this study. 2) The ambient air particulate concentrations, dry depositions were displayed as Airport > Harbor > Farmland during the night time sampling period. However, dry deposition velocities were shown as Farmland > Harbor > Airport for this study. 3) The metallic element Zn has the average highest concentrations at Airport, Harbor and Farmland among all the metallic elements during the day time sampling period in this study. 4) There were significant differences for the metallic elements (Cr, Cu, Zn and Pb) in dry depositions at these three characteristic sampling sites (HAF) for the night time sampling period. The only exception is metallic element Cd. It displayed that there were no significant differences for the metallic element Cd at the Airport and Farmland sampling sites during the night time sampling period. 5) The average highest values for the metallic element Cu in TSP among the three characteristic sampling sites occurred during the fall and winter seasons for this study. As for the dry depositions, the average highest values in dry deposition among the three characteristic sampling sites occurred during the spring and summer seasons for this study. 6) The average highest values for the metallic element Cd in TSP among the three characteristic sampling sites occurred during the spring and summer seasons for this study. As for the dry depositions, the average highest values in dry deposition among the three characteristic sampling sites occurred during fall and winter for this study.

The effect of vehicle protection on spine injuries in military conflict.

PubMed

Possley, Daniel R; Blair, James A; Freedman, Brett A; Schoenfeld, Andrew J; Lehman, Ronald A; Hsu, Joseph R

2012-09-01

To evaluate the effect of critical time periods in vehicle protection on spine injuries in the Global War on Terror. To characterize the effect of method of movement on and around the battlefield during Operation Enduring Freedom and Operation Iraqi Freedom from 2001 to 2009 in terms of its impact on the incidence and severity of spinal fractures sustained in combat. Retrospective study. Mounted and dismounted American servicemembers who were injured during combat. Extracted medical records of servicemembers identified in the Joint Theater Trauma Registry from October 2001 to December 2009. Methods of movement were defined as mounted or dismounted. Two time periods were compared. Cohorts were created for 2×2 analysis based on method of movement and the time period in which the injury occurred. Time period 1 and 2 were separated by April 1, 2007, which correlates with the initial fielding of the modern class of uparmored fighting vehicles with thickened underbelly armor and a V-shaped hull. Our four comparison groups were Dismounted in Time Period 1 (D1), Dismounted in Time Period 2 (D2), Mounted in Time Period 1 (M1), and Mounted in Time Period 2 (M2). In total, 1,819 spine fractures occurred over the entire study period. Four hundred seventy-two fractures (26%) were sustained in 145 servicemembers who were mounted at the time of injury, and 1,347 (74%) were sustained by 404 servicemembers who were dismounted (p<.0005). The incidence of fractures in the dismounted cohort (D1+D2) was significantly higher than in the mounted cohort (M1+M2) in both time periods (D1 vs. M1, 13.75 vs. 3.95/10,000 warrior-years [p<.001] and D2 vs. M2, 11.15 vs. 4.89/10,000 warrior-years [p<.0001]). In both the mounted and dismounted groups, the thoracolumbar (TL) junction was the most common site of injury (36.1%). Fractures to the TL junction (T10-L3) increased significantly from Time Period 1 to 2 (34% vs. 40% of all fractures, respectively, p=.03). Thoracolumbar fractures were significantly more severe in that there were more Arbeitsgemeinschaft fur Osteosynthesefragen/Magerl Type A injuries versus all TL fractures, 1.75 versus 2.68/10,000 or 27% of all spine fractures in Time Period 1 versus 40% in Time Period 2 (p=.007). Furthermore, there were significantly fewer minor fractures (spinous process and transverse process fractures) (p<.0001). In Time Period 2, significantly more TL spine fractures were classified as major fractures, according to the Denis classification system, in both the mounted and dismounted groups; M1 group, 61 of 226 (27%) versus the M2 group, 86 of 246 (34%) (p<.0005) and 173 of 786 (22%) in the D1 group versus 193 of 561 (34%) in the D2 group. The spinal cord injury (SCI) incidence did not change in the mounted groups in Time Period 1 (7 of 71, 9.9%) versus Time Period 2 (7 of 74, 9.5%) (p=.935). In the dismounted groups, SCI actually decreased from D1 (55 of 228, 24%) to D2 (28 of 176, 16%) (p=.0428). The incidence of spine fractures and SCI is significantly higher in dismounted operations. The data suggest that current uparmored vehicles convey greater protection against spinal fracture compared with dismounted operations in which servicemembers are engaged on foot, outside their vehicles. The TL junction is at greatest risk for spine fractures sustained in mounted and dismounted combat operations. Recently, the incidence of TL fractures, especially severe fractures, has significantly increased in mounted operations. Although there has been an increased incidence of TL spine fractures, in context of the number of servicemembers deployed in support of Operation Enduring Freedom/Operation Iraqi Freedom, these severe fractures still represent a relatively rare event. Published by Elsevier Inc.

Photometric Variability of the mCP Star CS Vir: Evolution of the Rotation Period

NASA Astrophysics Data System (ADS)

Ozuyar, D.; Sener, H. T.; Stevens, I. R.

2018-01-01

The aim of this study is to accurately calculate the rotational period of CS Vir by using STEREO observations and investigate a possible period variation of the star with the help of all accessible data. The STEREO data that cover 5-yr time interval between 2007 and 2011 are analysed by means of the Lomb-Scargle and Phase Dispersion Minimization methods. In order to obtain a reliable rotation period and its error value, computational algorithms such as the Levenberg-Marquardt and Monte Carlo simulation algorithms are applied to the data sets. Thus, the rotation period of CS Vir is improved to be 9.29572(12) d by using the 5-yr of combined data set. Also, the light elements are calculated as HJD max = 2454715.975(11) + 9d . 29572(12) × E + 9d . 78(1.13) × 10 - 8 × E 2 by means of the extremum times derived from the STEREO light curves and archives. Moreover, with this study, a period variation is revealed for the first time, and it is found that the period has lengthened by 0.66(8) s y-1, equivalent to 66 s per century. Additionally, a time-scale for a possible spin-down is calculated around τSD 106 yr. The differential rotation and magnetic braking are thought to be responsible of the mentioned rotational deceleration. It is deduced that the spin-down time-scale of the star is nearly three orders of magnitude shorter than its main-sequence lifetime (τMS 109 yr). It is, in return, suggested that the process of increase in the period might be reversible.

[Local fractal analysis of noise-like time series by all permutations method for 1-115 min periods].

PubMed

Panchelyuga, V A; Panchelyuga, M S

2015-01-01

Results of local fractal analysis of 329-per-day time series of 239Pu alpha-decay rate fluctuations by means of all permutations method (APM) are presented. The APM-analysis reveals in the time series some steady frequency set. The coincidence of the frequency set with the Earth natural oscillations was demonstrated. A short review of works by different authors who analyzed the time series of fluctuations in processes of different nature is given. We have shown that the periods observed in those works correspond to the periods revealed in our study. It points to a common mechanism of the phenomenon observed.

Changes in body size and physical characteristics of South African under-20 rugby union players over a 13-year period.

PubMed

Lombard, Wayne P; Durandt, Justin J; Masimla, Herman; Green, Mervin; Lambert, Michael I

2015-04-01

This study compared changes in the body size and physical characteristics of South African under-20 rugby union players over a 13-year period. A total of 453 South African under-20 players (forwards: n = 256 and backs: n = 197) underwent measurements of body mass, stature, muscular strength, endurance, and 10- and 40-m sprint times. A 2-way analysis of variance was used to determine significant differences for the main effects of position (forwards vs. backs) and time (1998-2010). The pooled data showed that forwards were significantly heavier (22%), taller (5%), and stronger (18%) than the backs. However, when 1 repetition maximum strength scores were adjusted for body mass, backs were stronger per kg body mass. Stature did not change over the 13-year period for both groups. There were, however, significant increases in muscular strength (50%), body mass (20%), and muscular endurance (50%). Furthermore, an improvement in sprint times over 40 (4%) and 10 m (7%) was evident over the period of the study. In conclusion, the players became heavier, stronger, taller, and improved their upper-body muscular endurance over the 13 years of the study. Furthermore, sprint times over 10 and 40 m improved over the same time period despite the increase in body mass. It can be speculated that the changes in physical characteristics of the players over time are possibly a consequence of (a) adaptations to the changing demands of the game and (b) advancements in training methods.

Prominence of scientific publications towards peri-implant complications in implantology: A bibliometric analysis using the H-classics method.

PubMed

Chiang, H-S; Huang, R-Y; Weng, P-W; Mau, L-P; Tsai, Y-W C; Chung, M-P; Chung, C-H; Yeh, H-W; Shieh, Y-S; Cheng, W-C

2018-03-01

Current bibliometric analyses of the evolving trends in research scope category across different time periods using the H-classics method in implantology are considerably limited. The purpose of this study was to identify the classic articles in implantology to analyse bibliometric characteristics and associated factors in implantology for the past four decades. H-Classics in implantology were identified within four time periods between 1977 and 2016, based on the h-index from the Scopus ® database. For each article, the principal bibliometric parameters of authorship, geographic origin, country origin, and institute origin, collaboration, centralisation, article type, scope of study and other associated factors were analysed in four time periods. A significant increase in mean numbers of authors per H-Classics was found across time. Both Europe and North America were the most productive region/country and steadily dominated this field in each time period. Collaborations of author, internationally and inter-institutionally had significantly increased across time. A significant decentralisation in authorships, institutes and journals was noted in past four decades. The journal of Clinical Oral Implant Researches has raised its importance for almost 30 years (1987-2016). Research on Complications, peri-implant infection/pathology/therapy had been increasing in production throughout each period. This is the first study to evaluate research trends in implantology in the past 40 years using the H-classics method, which through analysing via principle bibliometric characteristics reflected a historical perspective on evolutionary mainstream in the field. Prominence of research regarding complications may forecast innovative advancements in future. © 2018 John Wiley & Sons Ltd.

Time dependence of solid-particle impingement erosion of an aluminum alloy

NASA Technical Reports Server (NTRS)

Veerabhadrarao, P.; Buckley, D. H.

1983-01-01

Erosion studies were conducted on 6061-T6511 aluminum alloy by using jet impingement of glass beads and crushed glass particles to investigate the influence of exposure time on volume loss rate at different pressures. The results indicate a direct relationship between erosion-versus-time curves and pitmorphology (width, depth, and width-depth ratio)-versus-time curves for both glass forms. Extensive erosion data from the literature were analyzed to find the variations of erosion-rate-versus-time curves with respect to the type of device, the size and shape of erodent particles, the abrasive charge, the impact velocity, etc. Analysis of the experimental data, obtained with two forms of glass, resulted in three types of erosion-rate-versus-time curves: (1) curves with incubation, acceleration, and steadystate periods (type 1); (2) curves with incubation, acceleration, decleration, and steady-state periods (type 3); and (3) curves with incubation, acceleration, peak rate, and deceleration periods (type 4). The type 4 curve is a less frequently seen curve and was not reported in the literature. Analysis of extensive literature data generally indicated three types of erosion-rate-versus-time curves. Two types (types 1 and 3) were observed in the present study; the third type involves incubation (and deposition), acceleration, and steady-state periods (type 2). Examination of the extensive literature data indicated that it is absolutely necessary to consider the corresponding stages or periods of erosion in correlating and characterizing erosion resistance of a wide spectrum of ductile materials.

Evaluation of pre-hospital transport time of stroke patients to thrombolytic treatment.

PubMed

Simonsen, Sofie Amalie; Andresen, Morten; Michelsen, Lene; Viereck, Søren; Lippert, Freddy K; Iversen, Helle Klingenberg

2014-11-13

Effective treatment of stroke is time dependent. Pre-hospital management is an important link in reducing the time from occurrence of stroke symptoms to effective treatment. The aim of this study was to evaluate time used by emergency medical services (EMS) for stroke patients during a five-year period in order to identify potential delays and evaluate the reorganization of EMS in Copenhagen in 2009. We performed a retrospective analysis of ambulance records from stroke patients suitable for thrombolysis from 1 January 2006 to 7 July 2011. We noted response time from dispatch of the ambulance to arrival at the scene, on-scene time and transport time to the hospital-in total, alarm-to-door time. In addition, we noted baseline characteristics. We reviewed 481 records (58% male, median age 66 years). The median (IQR) alarm-to-door time in minutes was 41 (33-52), of which 18 (12-24) minutes were spent on scene. Response time was reduced from the period before to the period after reorganization (7 vs. 5 minutes, p <0.001). In a linear multiple regression model, higher patient age and longer distance to the hospital correlated with significantly longer transportation time (p <0.001). This study shows an unchanged alarm-to-door time of 41 minutes over a five-year period. Response time, but not total alarm-to-door time, was reduced during the five years. On-scene time constituted nearly half of the total alarm-to-door time and is thus a point of focus for improvement.

The Long and Short Incubation Periods of Plasmodium vivax Malaria in Korea: The Characteristics and Relating Factors

PubMed Central

Kim, Sun-Ja; Kim, Si-Heon; Jo, Soo-Nam; Gwack, Jin; Youn, Seung-Ki

2013-01-01

Background The cases of Plasmodium vivax malaria in Korea are mixed with long and short incubation periods. This study aims to define clinico-epidemiologic chracteristcs of Plasmodium vivax malaria in Korea. Materials and Methods We selected the civilian cases infected with P. vivax malaria in Korea from the epidemiological investigation data of 2001 to 2010, whose incubation periods could be estimated. The long and short incubation periods were defined by duration of infection and onset time, and the cases were compared by demographic factors and clinical symptom, infection and onset time. The correlation was analyzed between the proportion of cases in the infected region with the long incubation period and meteorological factors along with latitude. Results The length of the mean short and long incubation periods for the cases were 25.5 days and 329.4 days, respectively. The total number of the study subjects was 897, and the number cases of short and long incubation periods was 575 (64.1%) and 322 (35.9%), respectively. The aspect of incubation period showed a significant difference by region of infection; there was a higher proportion of long incubation period infection cases in Gangwon-do than in Gyeonggi-do and Incheon. The proportion of long incubation period cases showed significant correlation with latitude and temperature of August and September of the infected regions. Conclusions Incubation period of P. vivax malaria in Korea showed significant difference by infected region, infection and onset time and the proportion of long incubation period cases showed significant correlation with latitude and meteorological factors of the infected regions. PMID:24265966

The Long and Short Incubation Periods of Plasmodium vivax Malaria in Korea: The Characteristics and Relating Factors.

PubMed

Kim, Sun-Ja; Kim, Si-Heon; Jo, Soo-Nam; Gwack, Jin; Youn, Seung-Ki; Jang, Jae-Yeon

2013-06-01

The cases of Plasmodium vivax malaria in Korea are mixed with long and short incubation periods. This study aims to define clinico-epidemiologic chracteristcs of Plasmodium vivax malaria in Korea. We selected the civilian cases infected with P. vivax malaria in Korea from the epidemiological investigation data of 2001 to 2010, whose incubation periods could be estimated. The long and short incubation periods were defined by duration of infection and onset time, and the cases were compared by demographic factors and clinical symptom, infection and onset time. The correlation was analyzed between the proportion of cases in the infected region with the long incubation period and meteorological factors along with latitude. The length of the mean short and long incubation periods for the cases were 25.5 days and 329.4 days, respectively. The total number of the study subjects was 897, and the number cases of short and long incubation periods was 575 (64.1%) and 322 (35.9%), respectively. The aspect of incubation period showed a significant difference by region of infection; there was a higher proportion of long incubation period infection cases in Gangwon-do than in Gyeonggi-do and Incheon. The proportion of long incubation period cases showed significant correlation with latitude and temperature of August and September of the infected regions. Incubation period of P. vivax malaria in Korea showed significant difference by infected region, infection and onset time and the proportion of long incubation period cases showed significant correlation with latitude and meteorological factors of the infected regions.

Rehabilitation time before disability pension.

PubMed

Støver, Morten; Pape, Kristine; Johnsen, Roar; Fleten, Nils; Sund, Erik R; Claussen, Bjørgulf; Ose, Solveig Osborg; Bjørngaard, Johan Håkon

2012-10-30

The decision to grant a disability pension is usually the end of a long process of medical examinations, treatment and rehabilitation attempts. This study investigates to what extent the time spent on rehabilitation time prior to disability pension is associated with characteristics of the individual or the local employment and welfare office, measured as municipality variance. A study of 2,533 40 to 42 year olds who received disability pension over a period of 18 years. The logarithm of the rehabilitation time before granting a disability pension was analysed with multilevel regression. The rehabilitation time before a disability pension was granted ranged from 30 to 5,508 days. Baseline health characteristics were only moderately associated with rehabilitation time. Younger people and people with unemployment periods had longer rehabilitation time before a disability pension was granted. There were only minor differences in rehabilitation time between men and women and between different levels of education. Approximately 2% of the total variance in rehabilitation time could be attributed to the municipality of residence. There is a higher threshold for granting a disability pension to younger persons and those who are expecting periods of unemployment, which is reflected in the extended rehabilitation requirements for these groups. The longer rehabilitation period for persons with psychiatric disorders might reflect a lack of common knowledge on the working capacity of and the fitted rehabilitation programs for people with psychiatric disorders.

Rehabilitation time before disability pension

PubMed Central

2012-01-01

Background The decision to grant a disability pension is usually the end of a long process of medical examinations, treatment and rehabilitation attempts. This study investigates to what extent the time spent on rehabilitation time prior to disability pension is associated with characteristics of the individual or the local employment and welfare office, measured as municipality variance. Methods A study of 2,533 40 to 42 year olds who received disability pension over a period of 18 years. The logarithm of the rehabilitation time before granting a disability pension was analysed with multilevel regression. Results The rehabilitation time before a disability pension was granted ranged from 30 to 5,508 days. Baseline health characteristics were only moderately associated with rehabilitation time. Younger people and people with unemployment periods had longer rehabilitation time before a disability pension was granted. There were only minor differences in rehabilitation time between men and women and between different levels of education. Approximately 2% of the total variance in rehabilitation time could be attributed to the municipality of residence. Conclusions There is a higher threshold for granting a disability pension to younger persons and those who are expecting periods of unemployment, which is reflected in the extended rehabilitation requirements for these groups. The longer rehabilitation period for persons with psychiatric disorders might reflect a lack of common knowledge on the working capacity of and the fitted rehabilitation programs for people with psychiatric disorders. PMID:23110397

Left ventricular ejection time, not heart rate, is an independent correlate of aortic pulse wave velocity.

PubMed

Salvi, Paolo; Palombo, Carlo; Salvi, Giovanni Matteo; Labat, Carlos; Parati, Gianfranco; Benetos, Athanase

2013-12-01

Several studies showed a positive association between heart rate and pulse wave velocity, a sensitive marker of arterial stiffness. However, no study involving a large population has specifically addressed the dependence of pulse wave velocity on different components of the cardiac cycle. The aim of this study was to explore in subjects of different age the link between pulse wave velocity with heart period (the reciprocal of heart rate) and the temporal components of the cardiac cycle such as left ventricular ejection time and diastolic time. Carotid-femoral pulse wave velocity was assessed in 3,020 untreated subjects (1,107 men). Heart period, left ventricular ejection time, diastolic time, and early-systolic dP/dt were determined by carotid pulse wave analysis with high-fidelity applanation tonometry. An inverse association was found between pulse wave velocity and left ventricular ejection time at all ages (<25 years, r(2) = 0.043; 25-44 years, r(2) = 0.103; 45-64 years, r(2) = 0.079; 65-84 years, r(2) = 0.044; ≥ 85 years, r(2) = 0.022; P < 0.0001 for all). A significant (P < 0.0001) negative but always weaker correlation between pulse wave velocity and heart period was also found, with the exception of the youngest subjects (P = 0.20). A significant positive correlation was also found between pulse wave velocity and dP/dt (P < 0.0001). With multiple stepwise regression analysis, left ventricular ejection time and dP/dt remained the only determinant of pulse wave velocity at all ages, whereas the contribution of heart period no longer became significant. Our data demonstrate that pulse wave velocity is more closely related to left ventricular systolic function than to heart period. This may have methodological and pathophysiological implications.

Discretization and control of an SEIR epidemic model under equilibrium Wiener noise disturbances

NASA Astrophysics Data System (ADS)

Alonso, Santiago; De la Sen, Manuel; Nistal, Raul; Ibeas, Asier

2017-11-01

A discretized SEIR epidemic model, subject to Wiener noise disturbances of the equilibrium points, is studied. The discrete-time model is got from a general discretization technique applied to its continuous-time counterpart so that its behaviour be close to its continuous-time counterpart irrespective of the size of the discretization period. The positivity and stability of a normalized version of such a discrete-time model are emphasized. The paper also proposes the design of a periodic impulsive vaccination which is periodically injected to the susceptible subpopulation in order to eradicate the propagation of the disease or, at least, to reduce its unsuitable infective effects within the potentially susceptible subpopulation. The existence and asymptotic stability of a disease-free periodic solution are proved. In particular, both the exposed and infectious subpopulations converge asymptotically to zero as time tends to infinity while the normalized subpopulations of susceptible and recovered by immunization oscillate.

Trends in Worker Hearing Loss by Industry Sector, 1981–2010

PubMed Central

Masterson, Elizabeth A.; Deddens, James A.; Themann, Christa L.; Bertke, Stephen; Calvert, Geoffrey M.

2015-01-01

Background The purpose of this study was to estimate the incidence and prevalence of hearing loss for noise-exposed U.S. workers by industry sector and 5-year time period, covering 30 years. Methods Audiograms for 1.8 million workers from 1981–2010 were examined. Incidence and prevalence were estimated by industry sector and time period. The adjusted risk of incident hearing loss within each time period and industry sector as compared with a reference time period was also estimated. Results The adjusted risk for incident hearing loss decreased over time when all industry sectors were combined. However, the risk remained high for workers in Healthcare and Social Assistance, and the prevalence was consistently high for Mining and Construction workers. Conclusions While progress has been made in reducing the risk of incident hearing loss within most industry sectors, additional efforts are needed within Mining, Construction and Healthcare and Social Assistance. PMID:25690583

Life course epidemiology: Modeling educational attainment with administrative data.

PubMed

Roos, Leslie L; Wall-Wieler, Elizabeth

2017-01-01

Understanding the processes across childhood and adolescence that affect later life inequalities depends on many variables for a large number of individuals measured over substantial time periods. Linkable administrative data were used to generate birth cohorts and to study pathways of inequity in childhood and early adolescence leading to differences in educational attainment. Advantages and disadvantages of using large administrative data bases for such research were highlighted. Children born in Manitoba, Canada between 1982 and 1995 were followed until age 19 (N = 89,763), with many time-invariant measures serving as controls. Five time-varying predictors of high school graduation-three social and two health-were modelled using logistic regression and a framework for examining predictors across the life course. For each time-varying predictor, six temporal patterns were tested: full, accumulation of risk, sensitive period, and three critical period models. Predictors measured in early adolescence generated the highest odds ratios, suggesting the importance of adolescence. Full models provided the best fit for the three time-varying social measures. Residence in a low-income neighborhood was a particularly influential predictor of not graduating from high school. The transmission of risk across developmental periods was also highlighted; exposure in one period had significant implications for subsequent life stages. This study advances life course epidemiology, using administrative data to clarify the relationships among several measures of social behavior, cognitive development, and health. Analyses of temporal patterns can be useful in studying such other outcomes as educational achievement, teen pregnancy, and workforce participation.

Mobile App to Reduce Inactivity in Sedentary Overweight Women.

PubMed

Finkelstein, Joseph; Bedra, McKenzie; Li, Xuan; Wood, Jeffrey; Ouyang, Pamela

2015-01-01

Recent studies demonstrated that the duration of inactivity (sedentary state) is independently associated with increased risk of cardiovascular disease. Our goal was to develop the technology that can measure the amount of inactivity in real time, remind a person that a preprogrammed period of inactivity has occurred and encourage a period of activity, and provide web-based feedback with tailored information to the participant and investigators. Once it was developed, we carried out a pilot study in a group of sedentary overweight women. The objective of the study was to assess potential of the mobile app to reduce inactivity in our target population. A randomized crossover design was employed with study subjects randomly assigned to a 4-week each "message-on" and "message-off" periods. Out of 30 enrolled subjects, 27 completed the study. The average age of particpants was 52±12; BMI: 37±6; 47% were white and 47% were African American. Overall, inactivity was significantly lower (p<0.02) during "message-on" periods (24.6%) as compared to the "message-off" periods (30.4%). We conluded that mobile app monitoring inactivity and providing a real-time notification when inactivity period exceeds healthy limits was able to significantly reduce inactivity periods in overweight sedentary women.

Rushed, unhappy, and drained: an experience sampling study of relations between time pressure, perceived control, mood, and emotional exhaustion in a group of accountants.

PubMed

Teuchmann, K; Totterdell, P; Parker, S K

1999-01-01

Experience sampling methodology was used to examine how work demands translate into acute changes in affective response and thence into chronic response. Seven accountants reported their reactions 3 times a day for 4 weeks on pocket computers. Aggregated analysis showed that mood and emotional exhaustion fluctuated in parallel with time pressure over time. Disaggregated time-series analysis confirmed the direct impact of high-demand periods on the perception of control, time pressure, and mood and the indirect impact on emotional exhaustion. A curvilinear relationship between time pressure and emotional exhaustion was shown. The relationships between work demands and emotional exhaustion changed between high-demand periods and normal working periods. The results suggest that enhancing perceived control may alleviate the negative effects of time pressure.

Boundedness and almost Periodicity in Time of Solutions of Evolutionary Variational Inequalities

NASA Astrophysics Data System (ADS)

Pankov, A. A.

1983-04-01

In this paper existence theorems are obtained for the solutions of abstract parabolic variational inequalities, which are bounded with respect to time (in the Stepanov and L^\\infty norms). The regularity and almost periodicity properties of such solutions are studied. Theorems are also established concerning their solvability in spaces of Besicovitch almost periodic functions. The majority of the results are obtained without any compactness assumptions. Bibliography: 30 titles.

A Catalog of Visual Double and Multiple Stars With Eclipsing Components

DTIC Science & Technology

2009-08-01

astrometric data were analyzed, resulting in new orbits for eight systems and new times of minimum light for a number of the eclipsing binaries. Some...analyses; one especially productive source is the study of the long- time behav- ior of the period of an EB. As might be expected, the longer the time ...span of conjunction time measurements, or times of min- imum light, the greater the chance of detecting a long-period orbit due to an additional

Observational safety study of specific outcomes after trivalent cell culture seasonal influenza vaccination (Optaflu® ) among adults in THIN database of electronic UK primary healthcare records.

PubMed

Hall, Gillian C; Davies, Paul T G; Karim, M Yousuf; Haag, Mendel D M; O'Leary, Caroline

2018-01-01

To investigate the safety of trivalent seasonal influenza vaccine (TIVc) (Optaflu ® ), the first cell culture seasonal trivalent influenza vaccine available in Europe. Codes and unstructured text in adult electronic healthcare records (The Health Improvement Network) were searched for a TIVc brand name or batch number and possible outcomes within a 3 month pre- to 6 month post-TIVc exposure study period (2012-2015). The outcomes were severe allergic reactions, Bell's palsy, convulsions, demyelination, paresthesia, noninfectious encephalitis, neuritis (optic and brachial), vasculitis, inflammatory bowel disease, and thrombocytopenia. Risk periods were defined based on biologically plausible time frame postvaccination when an outcome caused by the vaccine might be expected to occur. Possible outcomes were adjudicated against outcome specific case definitions and a date of onset assigned by using electronic and other medical records. Observed (risk period) to expected (outside risk and preexposure periods) rate ratios, postexposure incidence, and plots of time from exposure to outcome were reported. Sixteen of 1011 events from 4578 exposures fulfilled a primary case definition and had a date of onset during the study period. Three were in observed time. The observed-to-expected rate ratios were (3.3, 95% CI 0.3, 31.7) for convulsions and (1.5, 95% CI 0.2, 14.9) for thrombocytopenia with 1 outcome each in observed time. There was 1 incident inflammatory bowel disease in observed, but none in expected, time. The small sample size restricts interpretation; however, no hypothesis of an increased risk of a study outcome was generated. Adjudication of events against case definitions to reduce misclassification of onset and outcomes allowed use of precise risk periods. KEY POINTS This observational study did not generate a hypothesis of an association between the first cell-culture seasonal influenza vaccination available in the European Union and any of the study outcomes (severe allergic reactions, Bell's palsy, convulsions, demyelination, paresthesia, noninfectious encephalitis, neuritis [optic and brachial], vasculitis, inflammatory bowel disease [IBD], and thrombocytopenia). The small sample size limits interpretation of the results. The review of each possible outcome identified from electronic healthcare records against case definitions was included to minimize misclassification of time and outcomes and allow the use of precise risk-periods in an observed-to-expected within cohort analysis. Plots of time from exposure to outcome were included to assess the risk windows. Copyright © 2017 John Wiley & Sons, Ltd.

Analysis of the impact of crude oil price fluctuations on China's stock market in different periods-Based on time series network model

NASA Astrophysics Data System (ADS)

An, Yang; Sun, Mei; Gao, Cuixia; Han, Dun; Li, Xiuming

2018-02-01

This paper studies the influence of Brent oil price fluctuations on the stock prices of China's two distinct blocks, namely, the petrochemical block and the electric equipment and new energy block, applying the Shannon entropy of information theory. The co-movement trend of crude oil price and stock prices is divided into different fluctuation patterns with the coarse-graining method. Then, the bivariate time series network model is established for the two blocks stock in five different periods. By joint analysis of the network-oriented metrics, the key modes and underlying evolutionary mechanisms were identified. The results show that the both networks have different fluctuation characteristics in different periods. Their co-movement patterns are clustered in some key modes and conversion intermediaries. The study not only reveals the lag effect of crude oil price fluctuations on the stock in Chinese industry blocks but also verifies the necessity of research on special periods, and suggests that the government should use different energy policies to stabilize market volatility in different periods. A new way is provided to study the unidirectional influence between multiple variables or complex time series.

Understanding the effects of time on collaborative learning processes in problem based learning: a mixed methods study.

PubMed

Hommes, J; Van den Bossche, P; de Grave, W; Bos, G; Schuwirth, L; Scherpbier, A

2014-10-01

Little is known how time influences collaborative learning groups in medical education. Therefore a thorough exploration of the development of learning processes over time was undertaken in an undergraduate PBL curriculum over 18 months. A mixed-methods triangulation design was used. First, the quantitative study measured how various learning processes developed within and over three periods in the first 1,5 study years of an undergraduate curriculum. Next, a qualitative study using semi-structured individual interviews focused on detailed development of group processes driving collaborative learning during one period in seven tutorial groups. The hierarchic multilevel analyses of the quantitative data showed that a varying combination of group processes developed within and over the three observed periods. The qualitative study illustrated development in psychological safety, interdependence, potency, group learning behaviour, social and task cohesion. Two new processes emerged: 'transactive memory' and 'convergence in mental models'. The results indicate that groups are dynamic social systems with numerous contextual influences. Future research should thus include time as an important influence on collaborative learning. Practical implications are discussed.

Time-reversibility and particle sedimentation

NASA Technical Reports Server (NTRS)

Golubitsky, Martin; Krupa, Martin; Lim, Chjan

1991-01-01

This paper studies an ODE model, called the Stokeslet model, and describes sedimentation of small clusters of particles in a highly viscous fluid. This model has a trivial solution in which the n particles arrange themselves at the vertices of a regular n-sided polygon. When n = 3, Hocking and Caflisch et al. (1988) proved the existence of periodic motion (in the frame moving with the center of gravity in the cluster) in which the particles form an isosceles triangle. Here, the study of periodic and quasi-periodic solutions of the Stokeslet model is continued, with emphasis on the spatial and time-reversal symmetry of the model. For three particles, the existence of a second family of periodic solutions and a family of quasi-periodic solutions is proved. It is also indicated how the methods generalize to the case of n particles.

How reliable an indicator of inflammation is myeloperoxidase activity?

PubMed

Faith, Minnie; Sukumaran, Abitha; Pulimood, Anna B; Jacob, Molly

2008-10-01

Myeloperoxidase (MPO) and interleukin-6 (IL-6) are often used as markers of inflammation. The aim of this study was to ascertain whether MPO activity is as reliable as IL-6 as an indicator of inflammation. Inflammation was induced in mice, using either turpentine or indomethacin. Duodenal tissue was removed from these animals at various time periods ranging from 6 h to 7 days later. Concentrations of IL-6 and MPO activity were estimated in the tissue. Histopathological examination was also carried out at some of the time periods to determine the presence of neutrophil infiltration in turpentine-treated mice. Concentrations of IL-6 and MPO activity were significantly higher in tissue that had been treated with the agents used, at all the time periods studied, when compared with corresponding control tissue. Fold-increases in MPO activity were higher than fold-increases in IL-6. Concentrations of the 2 parameters showed significant positive correlation. Histopathological examination did not show significantly higher numbers of neutrophils infiltrating the tissue in response to turpentine, at the time periods studied. Estimation of MPO activity is a reliable indicator of inflammation, being more sensitive than histopathological examination of tissue and as good as measurement of IL-6 concentrations.

Long-Term Prediction of the Arctic Ionospheric TEC Based on Time-Varying Periodograms

PubMed Central

Liu, Jingbin; Chen, Ruizhi; Wang, Zemin; An, Jiachun; Hyyppä, Juha

2014-01-01

Knowledge of the polar ionospheric total electron content (TEC) and its future variations is of scientific and engineering relevance. In this study, a new method is developed to predict Arctic mean TEC on the scale of a solar cycle using previous data covering 14 years. The Arctic TEC is derived from global positioning system measurements using the spherical cap harmonic analysis mapping method. The study indicates that the variability of the Arctic TEC results in highly time-varying periodograms, which are utilized for prediction in the proposed method. The TEC time series is divided into two components of periodic oscillations and the average TEC. The newly developed method of TEC prediction is based on an extrapolation method that requires no input of physical observations of the time interval of prediction, and it is performed in both temporally backward and forward directions by summing the extrapolation of the two components. The backward prediction indicates that the Arctic TEC variability includes a 9 years period for the study duration, in addition to the well-established periods. The long-term prediction has an uncertainty of 4.8–5.6 TECU for different period sets. PMID:25369066

A Social Network Analysis of 140 Community‐Academic Partnerships for Health: Examining the Healthier Wisconsin Partnership Program

PubMed Central

Ahmed, Syed M.; Maurana, Cheryl A.; DeFino, Mia C.; Brewer, Devon D.

2015-01-01

Abstract Introduction: Social Network Analysis (SNA) provides an important, underutilized approach to evaluating Community Academic Partnerships for Health (CAPHs). This study examines administrative data from 140 CAPHs funded by the Healthier Wisconsin Partnership Program (HWPP). Methods: Funder data was normalized to maximize number of interconnections between funded projects and 318 non‐redundant community partner organizations in a dual mode analysis, examining the period from 2003–2013.Two strategic planning periods, 2003–2008 vs. 2009–2014, allowed temporal comparison. Results: Connectivity of the network was largely unchanged over time, with most projects and partner organizations connected to a single large component in both time periods. Inter‐partner ties formed in HWPP projects were transient. Most community partners were only involved in projects during one strategic time period. Community organizations participating in both time periods were involved in significantly more projects during the first time period than partners participating in the first time period only (Cohen's d = 0.93). Discussion: This approach represents a significant step toward using objective (non‐survey) data for large clusters of health partnerships and has implications for translational science in community settings. Considerations for government, funders, and communities are offered. Examining partnerships within health priority areas, orphaned projects, and faculty ties to these networks are areas for future research. PMID:25974413

Is the timing of surgery associated with avascular necrosis after unstable slipped capital femoral epiphysis? A multicenter study.

PubMed

Kohno, Yusuke; Nakashima, Yasuharu; Kitano, Toshio; Irie, Taichi; Kita, Atsushi; Nakamura, Tomoyuki; Endo, Hirosuke; Fujii, Yosuke; Kuroda, Takayuki; Mitani, Shigeru; Kitoh, Hiroshi; Matsushita, Masaki; Hattori, Tadashi; Iwata, Koji; Iwamoto, Yukihide

2017-01-01

An unstable slipped capital femoral epiphysis (SCFE) is associated with a high rate of avascular necrosis (AVN). The etiology of AVN seems to be multifactorial, although it is not thoroughly known. The aims of our study were to determine the rate of AVN after an unstable SCFE and to investigate the risk factors for AVN, specifically evaluating the notion of an "unsafe window", during which medical interventions would increase the risk for AVN. This retrospective multicenter study included 60 patients with an unstable SCFE diagnosed between 1985 and 2014. Timing of surgery was evaluated for three time periods, from acute onset of symptoms to surgery: period I, <24 h; period II, between 24 h and 7 days; and period III, >7 days. Multivariate logistic regression analysis was used to identify risk factors for AVN. Closed reduction and pinning was performed in 43 patients and in situ pinning in 17. Among these cases, 16 patients (27%) developed AVN. The rate of AVN was significantly higher in patients treated by closed reduction and pinning (15/43, 35%) than in those treated by in situ pinning (1/17, 5.9%) (p = 0.022). In patients treated by closed reduction and pinning, the incidence of AVN was 2/11 (18%) in period I, 10/13 (77%) in period II and 3/15 (20%) in period III, showing the significantly higher rate in period II (p = 0.002). The surgery provided in period II was identified as an independent risk factor for the development of AVN. Our rate of AVN was 27% using two classical treatment methods. Time-to-surgery, between 24 h and 7 days, was independently associated with AVN, supporting the possible existence of an "unsafe window" in patients with unstable SCFE treated by closed reduction and pinning. Copyright © 2016 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

Changes in duration of dry and wet spells associated with air temperatures in Russia

NASA Astrophysics Data System (ADS)

Ye, Hengchun

2018-03-01

This study uses daily precipitation records from 517 Russian stations (1966-2010) to examine the relationships between continuous dry and wet day duration and surface air temperature for all four seasons. The study found that both mean and extreme durations of dry periods increase with air temperature at about 7.0% (0.24 day/°C) and 7.7% (0.86 day/°C) respectively, while those of wet periods decrease at about 1.3% (-0.02 day/°C) and 2.2% (-0.10 day/°C) respectively averaged over the entire study region during summer. An increase in the duration of dry periods with higher air temperature is also found in other seasons at locations with a mean seasonal air temperature of about -5 °C or higher. Opposite relationships of shorter durations of dry periods and longer wet periods associated with higher air temperature are observed over the northern part of the study region in winter. The changes in durations of both dry and wet periods have significant correlations with the changes in total dry and wet days but are about 2.5 times higher for dry periods and 0.5 times lower for wet periods. The study also found that locations with longer durations of dry periods experience faster rates of increase in air temperature, suggesting the likelihood of exacerbating drought severity in drier and/or warmer locations for all seasons.

Effect of polaprezinc on oral mucositis, irradiation period, and time to discharge in patients with head and neck cancer.

PubMed

Suzuki, Akio; Kobayashi, Ryo; Shakui, Toshinobu; Kubota, Yukimasa; Fukita, Masaharu; Kuze, Bunya; Aoki, Mitsuhiro; Sugiyama, Tadashi; Mizuta, Keisuke; Itoh, Yoshinori

2016-09-01

The purpose of the present study was to determine whether polaprezinc suspension in sodium alginate (P-AG) reduces the irradiation period and time to discharge after completion of radiotherapy in patients with head and neck cancer. The incidence and severity of oral mucositis, the irradiation period, and the time to discharge in patients who received radiotherapy with head and neck cancer were investigated retrospectively from the medical records. The incidence of grade 3 oral mucositis was significantly lower in the P-AG group than in the control group (16.5% vs 52.0%; p = .0003). P-AG also significantly reduced median duration of radiotherapy (hazard ratio [HR] = 0.557; 95% confidence interval [CI] = 0.357-0.871; p = .0149) and median time to discharge after completion of radiotherapy (HR = 0.604; 95% CI = 0.386-0.946; p = .028). P-AG reduced the irradiation period and the time to discharge after completion of radiotherapy by preventing oral mucositis in patients with head and neck cancer. © 2016 Wiley Periodicals, Inc. Head Neck 38: 1387-1392, 2016. © 2016 Wiley Periodicals, Inc.

Cox model with interval-censored covariate in cohort studies.

PubMed

Ahn, Soohyun; Lim, Johan; Paik, Myunghee Cho; Sacco, Ralph L; Elkind, Mitchell S

2018-05-18

In cohort studies the outcome is often time to a particular event, and subjects are followed at regular intervals. Periodic visits may also monitor a secondary irreversible event influencing the event of primary interest, and a significant proportion of subjects develop the secondary event over the period of follow-up. The status of the secondary event serves as a time-varying covariate, but is recorded only at the times of the scheduled visits, generating incomplete time-varying covariates. While information on a typical time-varying covariate is missing for entire follow-up period except the visiting times, the status of the secondary event are unavailable only between visits where the status has changed, thus interval-censored. One may view interval-censored covariate of the secondary event status as missing time-varying covariates, yet missingness is partial since partial information is provided throughout the follow-up period. Current practice of using the latest observed status produces biased estimators, and the existing missing covariate techniques cannot accommodate the special feature of missingness due to interval censoring. To handle interval-censored covariates in the Cox proportional hazards model, we propose an available-data estimator, a doubly robust-type estimator as well as the maximum likelihood estimator via EM algorithm and present their asymptotic properties. We also present practical approaches that are valid. We demonstrate the proposed methods using our motivating example from the Northern Manhattan Study. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effect of signals on two-route traffic system with real-time information

NASA Astrophysics Data System (ADS)

Tobita, Kazuhiro; Nagatani, Takashi

2012-12-01

We study the effect of signals on the vehicular traffic in the two-route system at the tour-time feedback strategy where the vehicles move ahead through a series of signals. The Nagel-Schreckenberg model is applied to the vehicular motion. The traffic signals are controlled by both cycle time and split. The tour times on two routes fluctuate periodically and alternately. The period increases with decreasing the split. Also, the tour time on each route varies with time by synchronizing with the density. The dependences of tour times and densities on both split and cycle time are clarified.

Long-term orbital period behaviour of low mass ratio contact binaries GR Vir and FP Boo

NASA Astrophysics Data System (ADS)

Ćetinkaya, Halil; Soydugan, Faruk

2017-02-01

In this study, we investigated orbital period variations of two low mass ratio contact binaries GR Vir and FP Boo based on published minima times. From the O-C analysis, it was found that FP Boo indicates orbital period decrease while the period of GR Vir is increasing. Mass transfer process was used to explain increase and decrease in the orbital periods. In the O-C diagrams of both systems periodic variations also exist. Cyclic changes can be explained as being the result of a light-travel time effect via a third component around the eclipsing binaries. In order to interpret of cyclic orbital period changes for GR Vir, which has late-type components, possible magnetic activity cycles of the components have been also considered.

The effect of temperature and extraction period of time on the chemicals content of emprit ginger ethanol extract (Zingiber officinale var. Rubrum)

NASA Astrophysics Data System (ADS)

Ratnaningrum, Diah; Endah, Een Sri; Pudjiraharti, Sri

2017-01-01

Research on extraction method of emprit ginger using ethanol with agitation of 100 rpm at different temperatures (ambient temperature, 40, and 50°C) and various extraction period of times (30, 60, and 90 minutes) was conducted. Analysis of chemicals content i.e. total phenolic and total flavonoid. The objective of this work was to study the effect of temperatures and extraction period of times on the chemicals content of its ethanol extract. Based on the results of the test, the highest content total flavonoid (5.17% w/w) was resulted at 40°C for 90 minutes, while the total phenolic content was not affected by either temperature or extraction period of times used. The content of total phenolic was around 2.39% to 2.65% w/w.

A photometric study of the nova-like variable TT Arietis with the MOST satellite

NASA Astrophysics Data System (ADS)

Vogt, N.; Chené, A.-N.; Moffat, A. F. J.; Matthews, J. M.; Kuschnig, R.; Guenther, D. B.; Rowe, J. F.; Rucinski, S. M.; Sasselov, D.; Weiss, W. W.

2013-12-01

Variability on all time scales between seconds and decades is typical for cataclysmic variables (CVs). One of the brightest and best studied CVs is TT Ari, a nova-like variable which belongs to the VY Scl subclass, characterized by occasional low states in their light curves. It is also known as a permanent superhumper at high state, revealing ``positive'' (PS> P0) as well as ``negative'' (PS< P0) superhumps, where PS is the period of the superhump and P0 the orbital period. TT Ari was observed by the Canadian space telescope MOST for about 230 hours nearly continuously in 2007, with a time resolution of 48 seconds. Here we analyze these data, obtaining a dominant ``negative'' superhump signal with a period PS = 0.1331 days and a mean amplitude of 0.09 mag. Strong flickering with amplitudes up to 0.2 mag and peak-to-peak time scales of 15-20 minutes is superimposed on the periodic variations. We found no indications for significant quasi-periodic oscillations with periods around 15 minutes, reported by other authors. We discuss the known superhump behaviour of TT Ari during the last five decades and conclude that our period value is at the upper limit of all hitherto determined ``negative'' superhump periods of TT Ari, before and after the MOST run.

Exact dynamics of a one dimensional Bose gas in a periodic time-dependent harmonic trap

NASA Astrophysics Data System (ADS)

Scopa, Stefano; Unterberger, Jéremie; Karevski, Dragi

2018-05-01

We study the unitary dynamics of a 1D gas of hard-core bosons trapped into a harmonic potential which varies periodically in time with frequency . Such periodic systems can be classified into orbits of different monodromies corresponding to two different physical situations, namely the case in which the bosonic cloud remains stable during the time-evolution and the case where it turns out to be unstable. In the present work we derive in the large particle number limit exact results for the stroboscopic evolution of the energy and particle densities in both physical situations.

Logic Model Checking of Time-Periodic Real-Time Systems

NASA Technical Reports Server (NTRS)

Florian, Mihai; Gamble, Ed; Holzmann, Gerard

2012-01-01

In this paper we report on the work we performed to extend the logic model checker SPIN with built-in support for the verification of periodic, real-time embedded software systems, as commonly used in aircraft, automobiles, and spacecraft. We first extended the SPIN verification algorithms to model priority based scheduling policies. Next, we added a library to support the modeling of periodic tasks. This library was used in a recent application of the SPIN model checker to verify the engine control software of an automobile, to study the feasibility of software triggers for unintended acceleration events.

Study of spectro-temporal variation in paleo-climatic marine proxy records using wavelet transformations

NASA Astrophysics Data System (ADS)

Pandey, Chhavi P.

2017-10-01

Wavelet analysis is a powerful mathematical and computational tool to study periodic phenomena in time series particu-larly in the presence of potential frequency changes in time. Continuous wavelet transformation (CWT) provides localised spectral information of the analysed dataset and in particular useful to study multiscale, nonstationary processes occurring over finite spatial and temporal domains. In the present work, oxygen-isotope ratio from the plantonic foraminifera species (viz. Globigerina bul-loides and Globigerinoides ruber) acquired from the broad central plateau of the Maldives ridge situated in south-eastern Arabian sea have been used as climate proxy. CWT of the time series generated using both the biofacies indicate spectro-temporal varia-tion of the natural climatic cycles. The dominant period resembles to the period of Milankovitch glacial-interglacial cycle. Apart from that, various other cycles are present in the time series. The results are in good agreement with the astronomical theory of paleoclimates and can provide better visualisation of Indian summer monsoon in the context of climate change.

Finding the Key Periods for Assimilating HJ-1A/B CCD Data and the WOFOST Model to Evaluate Heavy Metal Stress in Rice.

PubMed

Zhao, Shuang; Qian, Xu; Liu, Xiangnan; Xu, Zhao

2018-04-17

Accurately monitoring heavy metal stress in crops is vital for food security and agricultural production. The assimilation of remote sensing images into the World Food Studies (WOFOST) model provides an efficient way to solve this problem. In this study, we aimed at investigating the key periods of the assimilation framework for continuous monitoring of heavy metal stress in rice. The Harris algorithm was used for the leaf area index (LAI) curves to select the key period for an optimized assimilation. To obtain accurate LAI values, the measured dry weight of rice roots (WRT), which have been proven to be the most stress-sensitive indicator of heavy metal stress, were incorporated into the improved WOFOST model. Finally, the key periods, which contain four dominant time points, were used to select remote sensing images for the RS-WOFOST model for continuous monitoring of heavy metal stress. Compared with the key period which contains all the available remote sensing images, the results showed that the optimal key period can significantly improve the time efficiency of the assimilation framework by shortening the model operation time by more than 50%, while maintaining its accuracy. This result is highly significant when monitoring heavy metals in rice on a large-scale. Furthermore, it can also offer a reference for the timing of field measurements in monitoring heavy metal stress in rice.

Factors Associated with School Lunch Consumption: Reverse Recess and School "Brunch".

PubMed

Chapman, Leah Elizabeth; Cohen, Juliana; Canterberry, Melanie; Carton, Thomas W

2017-09-01

While school foods have become healthier under the Healthy, Hunger Free Kids Act, research suggests there is still substantial food waste in cafeterias. It is therefore necessary to study factors that can impact food consumption, including holding recess before lunch ("reverse recess") and starting lunch periods very early or very late. This study examined the association between the timing of recess (pre-lunch vs post-lunch recess), the timing of the lunch period, and food consumed by students at lunch. We conducted a secondary data analysis from a repeated cross-sectional design. An 8-week plate waste study examining 20,183 trays of food was conducted in New Orleans, LA, in 2014. The study involved 1,036 fourth- and fifth-grade students from eight public schools. We measured percent of entrées, fruit, vegetables, and milk consumed by students at lunch. We used mixed-model analyses, controlling for student sex, grade, and the timing of the lunch period, and examined the association between reverse recess and student lunch consumption. Mixed-model analyses controlling for student sex, grade, and recess status examined whether the timing of the lunch period was associated with student lunch consumption. On average, students with reverse recess consumed 5.1% more of their fruit than students with post-lunch recess (P=0.009), but there were no significant differences in entrées, vegetables, or milk intake. Compared to students with "midday" lunch periods, on average students with "early" lunch periods consumed 5.8% less of their entrées (P<0.001) and 4.5% less of their milk (P=0.047). Students with "late" lunch periods consumed 13.8% less of their entrées (P<0.001) and 15.9% less of their fruit (P<0.001). Reverse recess was associated with increased fruit consumption. "Early" lunch periods were associated with decreased entrée and milk consumption, and "late" lunch periods were associated with decreased entrée and fruit consumption. Additional research is recommended to determine whether these associations are causal. Copyright © 2017 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

Changes in Attenuated Total Reflection Fourier Transform Infrared Spectra as Blood Dries Out.

PubMed

Zhang, Yinming; Wang, Qi; Li, Bing; Wang, Zhijun; Li, Chengzhi; Yao, Yao; Huang, Ping; Wang, Zhenyuan

2017-05-01

The time since deposition (TSD) of a bloodstain is a valuable piece of evidence for forensic scientists to determine the time at which a crime took place. The objective of this study was to determine whether attenuated total reflection (ATR) Fourier transform infrared (FTIR) spectroscopy could be used to estimate the TSD of a bloodstain in a relatively early period (from 0 min to the time required for the bloodstain to dry out). For this purpose, we used ATR-FTIR to study the variation in absorbance at certain wavelengths as rat and human blood sample dried out. The absorbance at 3308/cm (A3308) was found to have a close correlation with the TSD during this time period, and the changes in A3308 during the drying of rat and human blood drops under the same controlled conditions showed similar results. The current study indicates that ATR-FTIR spectroscopy has potential as a tool for estimating TSD at early time periods of blood deposition. © 2016 American Academy of Forensic Sciences.

Sirenomelia in Argentina: Prevalence, geographic clusters and temporal trends analysis.

PubMed

Groisman, Boris; Liascovich, Rosa; Gili, Juan Antonio; Barbero, Pablo; Bidondo, María Paz

2016-07-01

Sirenomelia is a severe malformation of the lower body characterized by a single medial lower limb and a variable combination of visceral abnormalities. Given that Sirenomelia is a very rare birth defect, epidemiological studies are scarce. The aim of this study is to evaluate prevalence, geographic clusters and time trends of sirenomelia in Argentina, using data from the National Network of Congenital Anomalies of Argentina (RENAC) from November 2009 until December 2014. This is a descriptive study using data from the RENAC, a hospital-based surveillance system for newborns affected with major morphological congenital anomalies. We calculated sirenomelia prevalence throughout the period, searched for geographical clusters, and evaluated time trends. The prevalence of confirmed cases of sirenomelia throughout the period was 2.35 per 100,000 births. Cluster analysis showed no statistically significant geographical aggregates. Time-trends analysis showed that the prevalence was higher in years 2009 to 2010. The observed prevalence was higher than the observed in previous epidemiological studies in other geographic regions. We observed a likely real increase in the initial period of our study. We used strict diagnostic criteria, excluding cases that only had clinical diagnosis of sirenomelia. Therefore, real prevalence could be even higher. This study did not show any geographic clusters. Because etiology of sirenomelia has not yet been established, studies of epidemiological features of this defect may contribute to define its causes. Birth Defects Research (Part A) 106:604-611, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Instructional Planning Time: A Review of Existing Research and Educator Practice during the 2012-2013 School Year

ERIC Educational Resources Information Center

Hixson, Nate; Stohr, Amber D.; Hammer, Patricia Cahape

2013-01-01

A study of instructional planning periods was undertaken in late 2013 pursuant to West Virginia State Code §18A-4-14 which states: "The state board shall conduct a study on planning periods. The study shall include, but not be limited to, the appropriate length for planning periods at the various grade levels and for the different types of…

Changes in Case-Mix and Health Outcomes of Medicare Fee-for-Service Beneficiaries and Managed Care Enrollees During the Years 1992-2011.

PubMed

Koroukian, Siran M; Basu, Jayasree; Schiltz, Nicholas K; Navale, Suparna; Bakaki, Paul M; Warner, David F; Dor, Avi; Given, Charles W; Stange, Kurt C

2018-01-01

Recent studies suggest that managed care enrollees (MCEs) and fee-for-service beneficiaries (FFSBs) have become similar in case-mix over time; but comparisons of health outcomes have yielded mixed results. To examine changes in differentials between MCEs and FFSBs both in case-mix and health outcomes over time. Temporal study of the linked Health and Retirement Study (HRS) and Medicare data, comparing case-mix and health outcomes between MCEs and FFSBs across 3 time periods: 1992-1998, 1999-2004, and 2005-2011. We used multivariable analysis, stratified by, and pooled across the study periods. The unit of analysis was the person-wave (n=167,204). HRS participants who were also enrolled in Medicare. Outcome measures included self-reported fair/poor health, 2-year self-rated worse health, and 2-year mortality. Our main covariate was a composite measure of multimorbidity (MM), MM0-MM3, defined as the co-occurrence of chronic conditions, functional limitations, and/or geriatric syndromes. The case-mix differential between MCEs and FFSBs persisted over time. Results from multivariable models on the pooled data and incorporating interaction terms between managed care status and study period indicated that MCEs and FFSBs were as likely to die within 2 years from the HRS interview (P=0.073). This likelihood remained unchanged across the study periods. However, MCEs were more likely than FFSBs to report fair/poor health in the third study period (change in probability for the interaction term: 0.024, P=0.008), but less likely to rate their health worse in the last 2 years, albeit at borderline significance (change in probability: -0.021, P=0.059). Despite the persistence of selection bias, the differential in self-reported fair/poor status between MCEs and FFSBs seems to be closing over time.

Multicenter outpatient dinner/overnight reduction of hypoglycemia and increased time of glucose in target with a wearable artificial pancreas using modular model predictive control in adults with type 1 diabetes.

PubMed

Del Favero, S; Place, J; Kropff, J; Messori, M; Keith-Hynes, P; Visentin, R; Monaro, M; Galasso, S; Boscari, F; Toffanin, C; Di Palma, F; Lanzola, G; Scarpellini, S; Farret, A; Kovatchev, B; Avogaro, A; Bruttomesso, D; Magni, L; DeVries, J H; Cobelli, C; Renard, E

2015-05-01

To test in an outpatient setting the safety and efficacy of continuous subcutaneous insulin infusion (CSII) driven by a modular model predictive control (MMPC) algorithm informed by continuous glucose monitoring (CGM) measurement. 13 patients affected by type 1 diabetes participated to a non-randomized outpatient 42-h experiment that included two evening meals and overnight periods (in short, dinner & night periods). CSII was patient-driven during dinner & night period 1 and MMPC-driven during dinner&night period 2. The study was conducted in hotels, where patients could move around freely. A CGM system (G4 Platinum; Dexcom Inc., San Diego, CA, USA) and insulin pump (AccuChek Combo; Roche Diagnostics, Mannheim, Germany) were connected wirelessly to a smartphone-based platform (DiAs, Diabetes Assistant; University of Virginia, Charlottesville, VA, USA) during both periods. A significantly lower percentage of time spent with glucose levels <3.9 mmol/l was achieved in period 2 compared with period 1: 1.96 ± 4.56% vs 12.76 ± 15.84% (mean ± standard deviation, p < 0.01), together with a greater percentage of time spent in the 3.9-10 mmol/l target range: 83.56 ± 14.02% vs 62.43 ± 29.03% (p = 0.04). In addition, restricting the analysis to the overnight phases, a lower percentage of time spent with glucose levels <3.9 mmol/l (1.92 ± 4.89% vs 12.7 ± 19.75%; p = 0.03) was combined with a greater percentage of time spent in 3.9-10 mmol/l target range in period 2 compared with period 1 (92.16 ± 8.03% vs 63.97 ± 2.73%; p = 0.01). Average glucose levels were similar during both periods. The results suggest that MMPC managed by a wearable system is safe and effective during evening meal and overnight. Its sustained use during this period is currently being tested in an ongoing randomized 2-month study. © 2015 John Wiley & Sons Ltd.

Non-stationary dynamics in the bouncing ball: A wavelet perspective

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

Behera, Abhinna K., E-mail: abhinna@iiserkol.ac.in; Panigrahi, Prasanta K., E-mail: pprasanta@iiserkol.ac.in; Sekar Iyengar, A. N., E-mail: ansekar.iyengar@saha.ac.in

2014-12-01

The non-stationary dynamics of a bouncing ball, comprising both periodic as well as chaotic behavior, is studied through wavelet transform. The multi-scale characterization of the time series displays clear signatures of self-similarity, complex scaling behavior, and periodicity. Self-similar behavior is quantified by the generalized Hurst exponent, obtained through both wavelet based multi-fractal detrended fluctuation analysis and Fourier methods. The scale dependent variable window size of the wavelets aptly captures both the transients and non-stationary periodic behavior, including the phase synchronization of different modes. The optimal time-frequency localization of the continuous Morlet wavelet is found to delineate the scales corresponding tomore » neutral turbulence, viscous dissipation regions, and different time varying periodic modulations.« less

Impenetrability in Floquet Scattering in One Dimension

NASA Astrophysics Data System (ADS)

Volosniev, A. G.; Smith, D. H.

2018-07-01

We study the scattering off a time-periodic zero-range potential in one spatial dimension. We focus on the parameter regions that lead to zero-transmission probability (ZTP). For static potentials, ZTP leads to fermionization of distinguishable equal-mass particles. For time-periodic potentials, fermionization is prevented by the formation of evanescent waves.

Facebook and body image concern in adolescent girls: A prospective study.

PubMed

Tiggemann, Marika; Slater, Amy

2017-01-01

The primary aim of the study was to examine the relationship across time between Facebook use and body image concern in adolescent girls. A sample of 438 girls in the first two years (Years 8 and 9) of high school (aged 13-15 years) at Time 1 completed questionnaire measures of Facebook consumption and body image concerns, and again two years later (Time 2). Facebook involvement increased substantially over the two year time period. Body image concerns also increased. Number of Facebook friends was found to prospectively predict the observed increase in drive for thinness. On the other hand, internalization and body surveillance prospectively predicted the observed increase in number of Facebook friends. It was concluded that Facebook "friendships" represent a potent sociocultural force in the body image of adolescent girls. © 2016 Wiley Periodicals, Inc. (Int J Eat Disord 2017; 50:80-83). © 2016 Wiley Periodicals, Inc.

Quantum gates by periodic driving

PubMed Central

Shi, Z. C.; Wang, W.; Yi, X. X.

2016-01-01

Topological quantum computation has been extensively studied in the past decades due to its robustness against decoherence. One way to realize the topological quantum computation is by adiabatic evolutions—it requires relatively long time to complete a gate, so the speed of quantum computation slows down. In this work, we present a method to realize single qubit quantum gates by periodic driving. Compared to adiabatic evolution, the single qubit gates can be realized at a fixed time much shorter than that by adiabatic evolution. The driving fields can be sinusoidal or square-well field. With the sinusoidal driving field, we derive an expression for the total operation time in the high-frequency limit, and an exact analytical expression for the evolution operator without any approximations is given for the square well driving. This study suggests that the period driving could provide us with a new direction in regulations of the operation time in topological quantum computation. PMID:26911900

Quantum gates by periodic driving.

PubMed

Shi, Z C; Wang, W; Yi, X X

2016-02-25

Topological quantum computation has been extensively studied in the past decades due to its robustness against decoherence. One way to realize the topological quantum computation is by adiabatic evolutions-it requires relatively long time to complete a gate, so the speed of quantum computation slows down. In this work, we present a method to realize single qubit quantum gates by periodic driving. Compared to adiabatic evolution, the single qubit gates can be realized at a fixed time much shorter than that by adiabatic evolution. The driving fields can be sinusoidal or square-well field. With the sinusoidal driving field, we derive an expression for the total operation time in the high-frequency limit, and an exact analytical expression for the evolution operator without any approximations is given for the square well driving. This study suggests that the period driving could provide us with a new direction in regulations of the operation time in topological quantum computation.

Timing of neuron development in the rodent vestibular system

NASA Technical Reports Server (NTRS)

Keefe, J. R.

1982-01-01

The timing of cell generation (onset and duration) in the developing rat vestibular and proprioceptive systems is investigated. The results clearly indicate a defined time-span for generation of all neurons in the central nervous system nuclei studied. This cytogenetic period in both vestibular and proprioceptive sensory nuclei is determined to occur during and immediately after placentation, a potentially critical period for spaceflight exposure due to alterations in maternal physiology.

Effects of combined linear and nonlinear periodic training on physical fitness and competition times in finswimmers.

PubMed

Yu, Kyung-Hun; Suk, Min-Hwa; Kang, Shin-Woo; Shin, Yun-A

2014-10-01

The purpose of this study was to investigate the effect of combined linear and nonlinear periodic training on physical fitness and competition times in finswimmers. The linear resistance training model (6 days/week) and nonlinear underwater training (4 days/week) were applied to 12 finswimmers (age, 16.08± 1.44 yr; career, 3.78± 1.90 yr) for 12 weeks. Body composition measures included weight, body mass index (BMI), percent fat, and fat-free mass. Physical fitness measures included trunk flexion forward, trunk extension backward, sargent jump, 1-repetition-maximum (1 RM) squat, 1 RM dead lift, knee extension, knee flexion, trunk extension, trunk flexion, and competition times. Body composition and physical fitness were improved after the 12-week periodic training program. Weight, BMI, and percent fat were significantly decreased, and trunk flexion forward, trunk extension backward, sargent jump, 1 RM squat, 1 RM dead lift, and knee extension (right) were significantly increased. The 50- and 100-m times significantly decreased in all 12 athletes. After 12 weeks of training, all finswimmers who participated in this study improved their times in a public competition. These data indicate that combined linear and nonlinear periodic training enhanced the physical fitness and competition times in finswimmers.

Trends over time in congenital malformations in live-born children conceived after assisted reproductive technology.

PubMed

Henningsen, Anna-Karina A; Bergh, Christina; Skjaerven, Rolv; Tiitinen, Aila; Wennerholm, Ulla-Britt; Romundstad, Liv B; Gissler, Mika; Opdahl, Signe; Nyboe Andersen, Anders; Lidegaard, Øjvind; Forman, Julie L; Pinborg, Anja

2018-07-01

Children born after assisted reproductive technology, particularly singletons, have been shown to have an increased risk of congenital malformations compared with children born after spontaneous conception. We wished to study whether there has been a change in the past 20 years in the risk of major congenital malformations in children conceived after assisted reproductive technology compared with children spontaneously conceived. Population-based cohort study including 90 201 assisted reproductive technology children and 482 552 children spontaneously conceived, born in Denmark, Finland, Norway and Sweden. Both singletons and twins born after in vitro fertilization, intracytoplasmatic sperm injection and frozen embryo transfer were included. Data on children were taken from when the national Nordic assisted reproductive technology registries were established until 2007. Multiple logistic regression analyses were used to estimate the risks and adjusted odds ratios for congenital malformations in four time periods: 1988-1992, 1993-1997, 1998-2002 and 2003-2007. Only major malformations were included. The absolute risk for singletons of being born with a major malformation was 3.4% among assisted reproductive technology children vs. 2.9% among children spontaneously conceived during the study period. The relative risk of being born with a major congenital malformation between all assisted reproductive technology children and children spontaneously conceived remained similar through all four time periods (p = 0.39). However, we found that over time the number of children diagnosed with a major malformation increased in both groups across all four time periods. When comparing children conceived after assisted reproductive technology and spontaneously conceived, the relative risk of being born with a major congenital malformation did not change during the study period. © 2018 Nordic Federation of Societies of Obstetrics and Gynecology.

White noise effects of U.S. crude oil spot prices on stock prices of a publicly traded company: A case study cross-correlation analysis based on green energy management theory

NASA Astrophysics Data System (ADS)

Roberts, Peter M.

The purpose of this study was to examine white noise effects of U.S. crude oil spot prices on the stock prices of a green energy company. Epistemological, Phenomenological, Axiological and Ontological assumptions of Green Energy Management (GEM) Theory were utilized for selecting Air Products and Chemicals Inc. (APD) as the case study. Exxon Mobil (XOM) was used as a control for triangulation purposes. The period of time examined was between January of 1999 and December of 2008. Monthly stock prices for APD and XOM for the ten year period of time were collected from the New York Stock Exchange. Monthly U.S. crude oil spot prices for the ten year period of time were collected from the US Energy Information Administration. The data was entered into SPSS 17.0 software in order to conduct cross-correlation analysis. The six cross-correlation assumptions were satisfied in order to conduct a Cross-correlation Mirror Test (CCMT). The CCMT established the lag time direction and verified that U.S. crude oil spot prices serve as white noise for stock prices of APD and XOM. The Theory of Relative Weakness was employed in order to analyze the results. A 2 year period of time between December, 2006 and December, 2008 was examined. The correlation coefficient r = - .155 indicates that U.S. crude oil spot prices lead APD stock prices by 4 months. During the same 2 year period of time, U.S. crude oil spot prices lead XOM stock prices by 4 months at r = -.283. XOM stock prices and APD stock prices were positively correlated with 0 lag in time with a positive r = .566. The 4 month cycle was an exact match between APD stock prices, XOM stock prices and U.S. crude oil spot prices. The 4 month cycle was due to the random price fluctuation of U.S. crude oil spot prices that obscured the true stock prices of APD and XOM for the 2 year period of time.

43 CFR 10010.45 - Time periods.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Time periods. 10010.45 Section 10010.45... Environmental Impact Statements § 10010.45 Time periods. (a) The minimum review period for a draft EIS will be... proposed reductions in time periods or any extensions of time periods proposed by those agencies. ...

43 CFR 10010.45 - Time periods.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Time periods. 10010.45 Section 10010.45... Environmental Impact Statements § 10010.45 Time periods. (a) The minimum review period for a draft EIS will be... proposed reductions in time periods or any extensions of time periods proposed by those agencies. ...

43 CFR 10010.45 - Time periods.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Time periods. 10010.45 Section 10010.45... Environmental Impact Statements § 10010.45 Time periods. (a) The minimum review period for a draft EIS will be... proposed reductions in time periods or any extensions of time periods proposed by those agencies. ...

The Need for Future Alternatives: An Investigation of the Experiences and Future of Older Parents Caring for Offspring with Learning Disabilities over a Prolonged Period of Time

ERIC Educational Resources Information Center

Cairns, Deborah; Tolson, Debbie; Brown, Jayne; Darbyshire, Chris

2013-01-01

This article reports on the results of a qualitative study (in-depth interviews) carried out in the United Kingdom as part of a larger (two-phased) study investigating the experiences, health and future perspectives of older parent carers (six mothers and two fathers) of offspring with learning disabilities over a prolonged period of time. The…

Creep feeding effects on male Nellore calves influencing behavior and performance of their dams.

PubMed

Martins, Leandro Soares; Paulino, Mário Fonseca; Rennó, Luciana Navajas; Detmann, Edenio; de Almeida, Daniel Mageste; Ortega, Roman Maza; Moreno, Deilen Paff Sotelo; Cárdenas, Javier Enrique Garces

2017-12-01

The objective of the present study was to evaluate the effect of different schemes of calves' supplementation in a creep feeding system, on the behavior of Bos indicus calves and dams, and also the influence of the calves' supplementation on dams' performance. Forty-eight Nellore male calves (147 ± 7 kg body weight and 3 months of age) in the suckling phase and their dams (476 ± 9 kg and 6 years of age) were studied in a completely randomized design. The experiment was divided into two periods of 71 days. The treatments were 5- and 10-g supplement dry matter (DM)/kg BW day offered in periods 1 and 2, respectively (5S/10S); 10- and 5-g supplement DM/kg BW day offered in periods 1 and 2, respectively (10S/5S); 7.5-g supplement DM/kg BW day in both periods 1 and 2 (7.5S); and mineral mix ad libitum in both periods 1 and 2 (MM). No differences (P < 0.05) in body condition score (BCS), final body weight (FBW), and average daily gain (ADG) were found in dams' performance. Calves from MM treatment spent more time (P < 0.05) grazing than the supplemented calves from 5S/10S and 10S/5S treatments, in the first period. No difference in suckling time was found between the treatments (P > 0.05) in the first evaluated period. Calves from 10S/5S treatment spent more time suckling and less time eating supplements (P < 0.05) than 5S/10S treatment animals, in the second evaluated period. Dams of MM treatment's calves had more idle time and lower grazing time when compared with the mothers of calves from 5S/10S and 10S/5S treatments. It was concluded that different schedules of Nellore calves' supplementation on pasture do not affect their mothers' performance, and supplementation decreases the grazing time of calves in the suckling phase.

Cognitive effects of rhythmic auditory stimulation in Parkinson's disease: A P300 study.

PubMed

Lei, Juan; Conradi, Nadine; Abel, Cornelius; Frisch, Stefan; Brodski-Guerniero, Alla; Hildner, Marcel; Kell, Christian A; Kaiser, Jochen; Schmidt-Kassow, Maren

2018-05-16

Rhythmic auditory stimulation (RAS) may compensate dysfunctions of the basal ganglia (BG), involved with intrinsic evaluation of temporal intervals and action initiation or continuation. In the cognitive domain, RAS containing periodically presented tones facilitates young healthy participants' attention allocation to anticipated time points, indicated by better performance and larger P300 amplitudes to periodic compared to random stimuli. Additionally, active auditory-motor synchronization (AMS) leads to a more precise temporal encoding of stimuli via embodied timing encoding than stimulus presentation adapted to the participants' actual movements. Here we investigated the effect of RAS and AMS in Parkinson's disease (PD). 23 PD patients and 23 healthy age-matched controls underwent an auditory oddball task. We manipulated the timing (periodic/random/adaptive) and setting (pedaling/sitting still) of stimulation. While patients elicited a general timing effect, i.e., larger P300 amplitudes for periodic versus random tones for both, sitting and pedaling conditions, controls showed a timing effect only for the sitting but not for the pedaling condition. However, a correlation between P300 amplitudes and motor variability in the periodic pedaling condition was obtained in control participants only. We conclude that RAS facilitates attentional processing of temporally predictable external events in PD patients as well as healthy controls, but embodied timing encoding via body movement does not affect stimulus processing due to BG impairment in patients. Moreover, even with intact embodied timing encoding, such as healthy elderly, the effect of AMS depends on the degree of movement synchronization performance, which is very low in the current study. Copyright © 2018 Elsevier B.V. All rights reserved.

Unrestricted and Restricted Access to Sugammadex and Side Effect Profile in a Teaching Hospital Centre for Year 2014- Database Audit Study.

PubMed

Rao Kadam, Vasanth; Howell, Stuart

2018-02-01

Sugammadex is used for the rapid reversal of neuro muscular block. It was used on an unrestricted basis in our facility prior to July 2014 but has subsequently been restricted due to the removal of cost subsidies. Our aim is to determine the impact of restricting the use of Sugammadex on clinical outcomes. A retrospective audit was conducted for the period January 1st to December 31st 2014. Sugammadex use was unrestricted during the first 6 months of this period and restricted over the following period. Patients who had endotracheal intubation for any surgery were included in the audit. Non- intubated patients, patients with incomplete data and patients who were intubated and transferred to the intensive care unit were excluded. The Operating Room Information System and medical records were used to obtain information on the operating theatre time, post-anesthesia care unit time and side effects such as postoperative nausea and vomiting, oxygen-de-saturation during recovery and anaphylaxis; Sugammadex usage and cost data obtained from the hospital pharmacy. 1347 and 1302 patients were included for the unrestricted and restricted periods, respectively. There were no significant differences between the time periods with respect to patient characteristics (Age, ASA) or side effects (oxygen de-saturation, nausea). While mean time in theatre was similar across the time periods, mean recovery time was significantly longer during the restricted period (P < 0.0001). One case of anaphylaxis was reported during the restricted period while no cases occurred during the unrestricted period. Median Sugammadex dose was 200 mg and its usage dropped by 54% in the restricted time. The cost of sugammadex was $180 AUD and Neostigmine $1.80 AUD. Though unrestricting Sugammadex reduced recovery time but has had minimal impact on other clinical outcomes. Neostigmine represents a cheaper alternative and its use remains standard practice in our facility.

Timely Health Service Utilization of Older Foster Youth by Insurance Type.

PubMed

Day, Angelique; Curtis, Amy; Paul, Rajib; Allotey, Prince Addo; Crosby, Shantel

2016-01-01

To evaluate the impact of a policy change for older foster care youth from a fee-for-service (FFS) Medicaid program to health maintenance organization (HMO) providers on the timeliness of first well-child visits (health care physicals). A three-year retrospective study using linked administrative data collected by the Michigan Departments of Human Services and Community Health of 1,657 youth, ages 10-20 years, who were in foster care during the 2009-2012 study period was used to examine the odds of receiving a timely well-child visit within the recommended 30-day time frame controlling for race, age, days from foster care entry to Medicaid enrollment, and number of foster care placements. Youth entering foster care during the HMO period were more likely to receive a timely well-child visit than those in the FFS period (odds ratio, 2.46; 95% confidence interval, 1.84-3.29; p < .0001) and days to the first visit decreased from a median of 62 days for those who entered foster care during the FFS period to 29 days for the HMO period. Among the other factors examined, more than 14 days to Medicaid enrollment, being non-Hispanic black and having five or more placements were negatively associated with receipt of a timely first well-child visit. Those youth who entered foster care during the HMO period had significantly greater odds of receiving a timely first well-child visit; however, disparities in access to preventive health care remain a concern for minority foster care youth, those who experience delayed Medicaid enrollment and those who experienced multiple placements. Copyright © 2016 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Assessing the initial adaptability and impact of a mobile dictation and reporting system in the radiology department of an academic hospital

NASA Astrophysics Data System (ADS)

Gali, Raja L.; Dave, Jaydev K.

2017-03-01

Mobile Radiologist 360, rolled out as part of the voice dictation system upgrade from Nuance Powerscribe 5.0 to PS360 allows an attending radiologist to edit and sign-off a report assigned by a trainee or that has been started by the radiologist on a workstation. The purpose of this study was to evaluate the adoptability and impact of this application. Report turnaround time data was extracted from the RIS (GE-Centricity RIS-IC) for 60 days before- (period-1) and 60 days after- (period-2) the application implementation and then, for 60 days after end of period-2 (period-3). Adoptability of the application was evaluated using two metrics; first, the number of attending radiologists who signed-off reports using the application in periods 2 and 3, and second, the proportion of reports signed-off by the top five users of the mobile application using the application. Impact of the application was evaluated by comparing the time from initial dictation to final sign-off (time_PF) for the top five users of the mobile application to the time_PF by other five radiologists who did not use the application. 41% radiologists used the mobile application at least once during the study period; the proportion of cases signed-off using the mobile application ranged from 1% to 20%. ANOVA revealed no statistically significant effect of the mobile application system on time_PF (p=0.842). In conclusion, there was low initial adoptability and no impact of the mobile dictation and reporting system in reducing the time from initial dictation to final sign-off on a radiology report.

Alcohol and suicide in Russia, 1870-1894 and 1956-2005: evidence for the continuation of a harmful drinking culture across time?

PubMed

Stickley, Andrew; Jukkala, Tanya; Norström, Thor

2011-03-01

Previous research suggests that a strong relation exists between alcohol consumption and suicide in Soviet and post-Soviet Russia. This study extends this analysis across a much longer historical time frame by examining the relationship between heavy drinking and suicide in tsarist and post-World War II Russia. Using alcohol poisoning mortality data as a proxy for heavy drinking, time-series analytical modeling techniques were used to examine the strength of the alcohol-suicide relation in the provinces of European Russia in the period 1870-1894 and for Russia in 1956-2005. During 1870-1894, a decreasing trend was recorded in heavy drinking in Russia that contrasted with the sharp increase observed in this phenomenon in the post-World War II period. A rising trend in suicide was recorded in both study periods, although the increase was much greater in the latter period. The strength of the heavy drinking-suicide relation nevertheless remained unchanged across time, with a 10% increase in heavy drinking resulting in a 3.5% increase in suicide in tsarist Russia and a 3.8% increase in post-World War II Russia. Despite the innumerable societal changes that have occurred in Russia across the two study periods and the growth in the level of heavy drinking, the strength of the heavy drinking-suicide relation has remained unchanged across time. This suggests the continuation of a highly detrimental drinking culture where the heavy episodic drinking of distilled spirits (vodka) is an essential element in the alcohol-suicide association.

Periodic, Quasi-periodic and Chaotic Dynamics in Simple Gene Elements with Time Delays

PubMed Central

Suzuki, Yoko; Lu, Mingyang; Ben-Jacob, Eshel; Onuchic, José N.

2016-01-01

Regulatory gene circuit motifs play crucial roles in performing and maintaining vital cellular functions. Frequently, theoretical studies of gene circuits focus on steady-state behaviors and do not include time delays. In this study, the inclusion of time delays is shown to entirely change the time-dependent dynamics for even the simplest possible circuits with one and two gene elements with self and cross regulations. These elements can give rise to rich behaviors including periodic, quasi-periodic, weak chaotic, strong chaotic and intermittent dynamics. We introduce a special power-spectrum-based method to characterize and discriminate these dynamical modes quantitatively. Our simulation results suggest that, while a single negative feedback loop of either one- or two-gene element can only have periodic dynamics, the elements with two positive/negative feedback loops are the minimalist elements to have chaotic dynamics. These elements typically have one negative feedback loop that generates oscillations, and another unit that allows frequent switches among multiple steady states or between oscillatory and non-oscillatory dynamics. Possible dynamical features of several simple one- and two-gene elements are presented in details. Discussion is presented for possible roles of the chaotic behavior in the robustness of cellular functions and diseases, for example, in the context of cancer. PMID:26876008

Preoperative fasting times in elective surgical patients at a referral Hospital in Botswana.

PubMed

Abebe, Worknehe Agegnehu; Rukewe, Ambrose; Bekele, Negussie Alula; Stoffel, Moeng; Dichabeng, Mompelegi Nicoh; Shifa, Jemal Zeberga

2016-01-01

Adults and children are required to fast before anaesthesia to reduce the risk of regurgitation and aspiration of gastric contents. However, prolonged periods of fasting are unnecessary and may cause complications. This study was conducted to evaluate preoperative fasting period in our centre and compare it with the ASA recommendations and factors that influence fasting periods. This is a cross-sectional study of preoperative fasting times among elective surgical patients. A total numbers of 260 patients were interviewed as they arrived at the reception area of operating theatre using questionnaire. Majority of patients (98.1%) were instructed to fast from midnight. Fifteen patients (5.8%) reported that they were told the importance of preoperative fasting. The mean fasting period were 15.9±2.5 h (range 12.0-25.3 h) for solids and 15.3±2.3 h (range 12.0-22.0 h) for liquids. The mean duration of fasting was significantly longer for patients operated after midday compared to those operated before midday, p<0.001. The mean fasting periods were 7.65 times longer for clear liquid and 2.5 times for solids than the ASA guidelines. It is imperative that the Hospital should establish Preoperative fasting policies and teach the staff who should ensure compliance with guidelines.

Periodic, Quasi-periodic and Chaotic Dynamics in Simple Gene Elements with Time Delays

NASA Astrophysics Data System (ADS)

Suzuki, Yoko; Lu, Mingyang; Ben-Jacob, Eshel; Onuchic, José N.

2016-02-01

Regulatory gene circuit motifs play crucial roles in performing and maintaining vital cellular functions. Frequently, theoretical studies of gene circuits focus on steady-state behaviors and do not include time delays. In this study, the inclusion of time delays is shown to entirely change the time-dependent dynamics for even the simplest possible circuits with one and two gene elements with self and cross regulations. These elements can give rise to rich behaviors including periodic, quasi-periodic, weak chaotic, strong chaotic and intermittent dynamics. We introduce a special power-spectrum-based method to characterize and discriminate these dynamical modes quantitatively. Our simulation results suggest that, while a single negative feedback loop of either one- or two-gene element can only have periodic dynamics, the elements with two positive/negative feedback loops are the minimalist elements to have chaotic dynamics. These elements typically have one negative feedback loop that generates oscillations, and another unit that allows frequent switches among multiple steady states or between oscillatory and non-oscillatory dynamics. Possible dynamical features of several simple one- and two-gene elements are presented in details. Discussion is presented for possible roles of the chaotic behavior in the robustness of cellular functions and diseases, for example, in the context of cancer.

Evolution of the patient characteristics of candidates for radical prostatectomy and the results obtained with the technique.

PubMed

Sanchís-Bonet, A; Arribas-Gómez, I; Sánchez-Rodríguez, C; Sánchez-Chapado, M

2015-03-01

To evaluate the oncological profile and risk of biochemical recurrence of patients with prostate cancer who underwent radical prostatectomy based on the time period in which the patients were operated. To evaluate the differences in prostate-specific antigen (PSA) at diagnosis of patients with or without biochemical recurrence based on these time periods. Observation carried forward study of a cohort of 972 radical prostatectomies performed during 3 time periods (1994-2000, 2001-2006, 2007-2011). The importance of PSA at diagnosis on the time periods and on biochemical recurrence was assessed using a generalized linear model. The independent predictive behavior of biochemical recurrence was analyzed using Cox regression. The median follow-up was 38 (16-76) months. PSA levels at diagnosis were higher in the period 1994-2000 (12.97ng/mL, P<.001). Seventy-two percent of the patients from the period 2007-2011 were diagnosed as clinical stage T1c (P<.001), compared with 55% from the period 1994-2000. The percentage of extracapsular extension in the specimen decreased from 27% to 18% from the period 1994-2000 to the period 2007-2011 (p<.001). The percentage of patients with biochemical recurrence went from 38% to 14% from the first to the third period (P>.001). The difference between PSA levels at diagnosis for the patients with or without biochemical recurrence was independent of the period (P=.84). The period during which surgery was performed was not an independent predictive factor for biochemical recurrence (P=.09). Patients from the 2007-2011 period had less extracapsular disease in the radical prostatectomy. The period was not an independent predictive factor for biochemical recurrence. Copyright © 2014 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

Stability and predictors of change in salivary cortisol measures over six years: MESA.

PubMed

Wang, Xu; Sánchez, Brisa N; Golden, Sherita Hill; Shrager, Sandi; Kirschbaum, Clemens; Karlamangla, Arun S; Seeman, Teresa E; Roux, Ana V Diez

2014-11-01

A major challenge in characterizing features of the daily cortisol curve is variability in features over time. Few studies have examined the stability of daily features of the cortisol curve over long periods or the predictors of long term changes. Repeated salivary cortisol measures on 580 adults from the MESA Stress study were used to examine the stability of various features of the daily cortisol curve (wakeup value, the cortisol awakening response (CAR), the early and late decline slope and the area under the curve (AUC)), over short periods (several days) and long periods (approximately 6-years) and to investigate the association of demographic factors with the changes. Intraclass correlation coefficients (ICCs) were used to estimate the short and long term stability. Piecewise linear mixed models were used to assess factors associated with changes in features over time. For most features, short term stability (ICCs: 0.17-0.74) was higher than long term stability (ICCs: 0.05-0.42), and long term stability was highest when several days were averaged for each time point. The decline over the day showed the highest long term stability: when several days for each wave were averaged the stability of the daily decline slope across 6 years was similar (or higher) than the stability across short periods. AUC had high stability over short periods (ICCs: 0.65-0.74) but much lower stability across long periods (ICC: 0.05). All features of daily cortisol curve investigated changed significantly over the approximately 6 year follow-up period. The wakeup cortisol became higher; the CAR became smaller; both the early and late decline became flatter; and the AUC became larger. Hispanics experienced significantly larger increases in the wakeup value; and African-Americans and Hispanics showed less flattening over time of the early decline slope than Non-Hispanic Whites. Our findings have implications for characterization of features in studies linking cortisol to health outcomes. The presence of variability over time suggests opportunities for future investigation of the predictors of changes over time as well as the links between these changes and health outcomes. Copyright © 2014 Elsevier Ltd. All rights reserved.

Global exponential stability of positive periodic solution of the n-species impulsive Gilpin-Ayala competition model with discrete and distributed time delays.

PubMed

Zhao, Kaihong

2018-12-01

In this paper, we study the n-species impulsive Gilpin-Ayala competition model with discrete and distributed time delays. The existence of positive periodic solution is proved by employing the fixed point theorem on cones. By constructing appropriate Lyapunov functional, we also obtain the global exponential stability of the positive periodic solution of this system. As an application, an interesting example is provided to illustrate the validity of our main results.

An alternative way to evaluate chemistry-transport model variability

NASA Astrophysics Data System (ADS)

Menut, Laurent; Mailler, Sylvain; Bessagnet, Bertrand; Siour, Guillaume; Colette, Augustin; Couvidat, Florian; Meleux, Frédérik

2017-03-01

A simple and complementary model evaluation technique for regional chemistry transport is discussed. The methodology is based on the concept that we can learn about model performance by comparing the simulation results with observational data available for time periods other than the period originally targeted. First, the statistical indicators selected in this study (spatial and temporal correlations) are computed for a given time period, using colocated observation and simulation data in time and space. Second, the same indicators are used to calculate scores for several other years while conserving the spatial locations and Julian days of the year. The difference between the results provides useful insights on the model capability to reproduce the observed day-to-day and spatial variability. In order to synthesize the large amount of results, a new indicator is proposed, designed to compare several error statistics between all the years of validation and to quantify whether the period and area being studied were well captured by the model for the correct reasons.

Optical Studies of 15 Hard X-Ray Selected Cataclysmic Binaries

NASA Astrophysics Data System (ADS)

Halpern, Jules P.; Thorstensen, John R.; Cho, Patricia; Collver, Gabriel; Motsoaledi, Mokhine; Breytenbach, Hannes; Buckley, David A. H.; Woudt, Patrick A.

2018-06-01

We conducted time-resolved optical spectroscopy and/or time-series photometry of 15 cataclysmic binaries that were discovered in hard X-ray surveys by the Swift Burst Alert Telescope and the International Gamma-Ray Astrophysics Laboratory, with the goal of measuring their orbital periods and searching for spin periods. Four of the objects in this study are new optical identifications: Swift J0535.2+2830, Swift J2006.4+3645, IGR J21095+4322, and Swift J2116.5+5336. Coherent pulsations are detected from three objects for the first time, Swift J0535.2+2830 (1523 s), 2PBC J1911.4+1412 (747 s), and 1SWXRT J230642.7+550817 (464 s), indicating that they are intermediate polars (IPs). We find two new eclipsing systems in time-series photometry: 2PBC J0658.0‑1746, a polar with a period of 2.38 hr, and Swift J2116.5+5336, a disk system that has an eclipse period of 6.56 hr. Exact or approximate spectroscopic orbital periods are found for six additional targets. Of note is the long 4.637-day orbit for Swift J0623.9‑0939, which is revealed by the radial velocities of the photospheric absorption lines of the secondary star. We also discover a 12.76 hr orbital period for RX J2015.6+3711, which confirms that the previously detected 2.00 hr X-ray period from this star is the spin period of an IP, as inferred by Coti Zelati et al. These results support the conclusion that hard X-ray selection favors magnetic CVs, with IPs outnumbering polars.

How complete is the ISC-GEM Global Earthquake Catalog?

USGS Publications Warehouse

Michael, Andrew J.

2014-01-01

The International Seismological Centre, in collaboration with the Global Earthquake Model effort, has released a new global earthquake catalog, covering the time period from 1900 through the end of 2009. In order to use this catalog for global earthquake studies, I determined the magnitude of completeness (Mc) as a function of time by dividing the earthquakes shallower than 60 km into 7 time periods based on major changes in catalog processing and data availability and applying 4 objective methods to determine Mc, with uncertainties determined by non-parametric bootstrapping. Deeper events were divided into 2 time periods. Due to differences between the 4 methods, the final Mc was determined subjectively by examining the features that each method focused on in both the cumulative and binned magnitude frequency distributions. The time periods and Mc values for shallow events are: 1900-1917, Mc=7.7; 1918-1939, Mc=7.0; 1940-1954, Mc=6.8; 1955-1963, Mc=6.5; 1964-1975, Mc=6.0; 1976-2003, Mc=5.8; and 2004-2009, Mc=5.7. Using these Mc values for the longest time periods they are valid for (e.g. 1918-2009, 1940-2009,…) the shallow data fits a Gutenberg-Richter distribution with b=1.05 and a=8.3, within 1 standard deviation, with no declustering. The exception is for time periods that include 1900-1917 in which there are only 33 events with M≥ Mc and for those few data b=2.15±0.46. That result calls for further investigations for this time period, ideally having a larger number of earthquakes. For deep events, the results are Mc=7.1 for 1900-1963, although the early data are problematic; and Mc=5.7 for 1964-2009. For that later time period, b=0.99 and a=7.3.

Post partum depression and the psychosocial predictors in first-time fathers from northwestern China.

PubMed

Zhang, Yin-Ping; Zhang, Lu-Lu; Wei, Huan-Huan; Zhang, Yao; Zhang, Chun-Li; Porr, Caroline

2016-04-01

there is growing evidence that fathers also experience post partum depression (PPD). However, paternal PPD has been less studied than maternal PPD. Very few studies have investigated PPD in first-time fathers from northwestern China. the purpose of this study was to investigate the occurrence and predictors of depressive symptoms in first-time fathers from northwestern China. a longitudinal study was conducted involving 180 couples who were assessed at three time periods: 3 days, 2 weeks and 6 weeks after childbirth. Self-reported questionnaires including Edinburgh Postnatal Depression Scale (EPDS), Parenting Sense of Competence Scale (PSOC), and Kansas Marital Satisfaction Scale (KMSS) were administered to all participants during each time period. after childbirth 35 (21.1%) of the fathers at 3 days, 32 (20.4%) at 2 weeks and 20 (13.6%) at 6 weeks, indicated that they suffered from PPD. Paternal parental sense of competence, paternal marital satisfaction, and maternal depressive symptoms were among the main predictors for paternal PPD. the study results suggest that paternal PPD is a significant public health concern. Health professionals should focus attention on the psychological health among new fathers during the postpartum period; and, the psychosocial predictors should be considered and incorporated into clinical assessment and intervention of paternal PPD. Copyright © 2016 Elsevier Ltd. All rights reserved.

Stable and verifiable state estimation methods and systems with spacecraft applications

NASA Technical Reports Server (NTRS)

Li, Rongsheng (Inventor); Wu, Yeong-Wei Andy (Inventor)

2001-01-01

The stability of a recursive estimator process (e.g., a Kalman filter is assured for long time periods by periodically resetting an error covariance P(t.sub.n) of the system to a predetermined reset value P.sub.r. The recursive process is thus repetitively forced to start from a selected covariance and continue for a time period that is short compared to the system's total operational time period. The time period in which the process must maintain its numerical stability is significantly reduced as is the demand on the system's numerical stability. The process stability for an extended operational time period T.sub.o is verified by performing the resetting step at the end of at least one reset time period T.sub.r whose duration is less than the operational time period T.sub.o and then confirming stability of the process over the reset time period T.sub.r. Because the recursive process starts from a selected covariance at the beginning of each reset time period T.sub.r, confirming stability of the process over at least one reset time period substantially confirms stability over the longer operational time period T.sub.o.

Aspects of Clock Resetting in Flowering of Xanthium 1

PubMed Central

Papenfuss, Herbert D.; Salisbury, Frank B.

1967-01-01

Flowering is induced in Xanthium strumarium by a single dark period exceeding about 8.3 hours in length (the critical night). To study the mechanism which measures this dark period, plants were placed in growth chambers for about 2 days under constant light and temperature, given a phasing dark period terminated by an intervening light period (1 min to several hrs in duration), and finally a test dark period long enough normally to induce flowering. In some experiments, light interruptions during the test dark period were given to establish the time of maximum sensitivity. If the phasing dark period was less than 5 hours long, its termination by a light flash only broadened the subsequent time of maximum sensitivity to a light flash, but the critical night was delayed. In causing the delay, the end of the intervening light period was acting like the dusk signal which initiated time measurement at the beginning of the phasing dark period. If the phasing dark period was 6 hours or longer, time of maximum sensitivity during the subsequent test dark period was shifted by as much as 10 to 14 hours. In this case the light terminating the phasing dark period acted as a rephaser or a dawn signal. Following a 7.5-hour phasing dark period, intervening light periods of 1 minute to 5 hours did not shift the subsequent time of maximum sensitivity, but with intervening light periods longer than 5 hours, termination of the light acts clearly like a dusk signal. The clock appears to be suspended during intervening light periods longer than 5 to 15 hours. It is restarted by a dusk signal. There is an anomaly with intervening light periods of 10 to 13 hours, following which time of maximum sensitivity is actually less than the usual 8 hours after dusk. Ability of the clock in Xanthium to be rephased, suspended, restarted, or delayed, depending always upon conditions of the experiment, is characteristic of an oscillating timer and may confer upon this plant its ability to respond to a single inductive cycle. It is suggested that phytochrome may influence only the phase of the clock and not other aspects of flowering such as synthesis of flowering hormone. PMID:16656693

The Reliability of In-Training Assessment when Performance Improvement Is Taken into Account

ERIC Educational Resources Information Center

van Lohuizen, Mirjam T.; Kuks, Jan B. M.; van Hell, Elisabeth A.; Raat, A. N.; Stewart, Roy E.; Cohen-Schotanus, Janke

2010-01-01

During in-training assessment students are frequently assessed over a longer period of time and therefore it can be expected that their performance will improve. We studied whether there really is a measurable performance improvement when students are assessed over an extended period of time and how this improvement affects the reliability of the…

Action Learning in ActionAid Nepal: A Case Study

ERIC Educational Resources Information Center

Lustig, Patricia; Rai, Deep Ranjani

2009-01-01

This article describes an example of how action learning was used as a framework for an organisational intervention to fundamentally change the organisational culture over a period of time. It also identifies our learning over that period of time and what worked well (and not so well) in an International Non-Governmental Organisation in Nepal.

Welfare Returns and Temporary Time Limits: A Proportional Hazard Model

ERIC Educational Resources Information Center

Albert, Vicky N.; King, William C.; Iaci, Ross

2007-01-01

This study analyzes welfare returns for families who leave welfare for a "sit-out" period of 12 months in response to a temporary time limit requirement in Nevada. Findings reveal that relatively few families return for cash assistance after sitting out and that the majority who do return soon after their sit-out period is complete.…

Do PDAs Enhance the Organization and Memory Skills of Students with Cognitive Disabilities?

ERIC Educational Resources Information Center

Gillette, Yvonne; Depompei, Roberta

2008-01-01

The project studied the on-time behavior of 35 students with intellectual disabilities (ID) or traumatic brain injury (TBI) under three conditions--times and tasks list, paper planner, and two different personal data assistants (PDAs). Students participated for two 4-week periods, receiving one morning reminder during Period 1 and no reminders…

Experimental investigation of stress-inducing properties of system response times.

PubMed

Kuhmann, W

1989-03-01

System response times are regarded as a major stressor in human-computer interaction. In two earlier studies short (2s) and long (8s) response times were found to have differential effects on psychological, subjective, and performance variables, but results did not favour either response time. Therefore, in another laboratory study with 48 subjects in four independent groups working at a stimulated computer workplace, system response times of 2, 4, 6 and 8s were introduced in the same error detection task as used before, during 3 training and 5 working trials of 20 min each, and the same physiological, subjective and performance measures were obtained. There were no global effects on physiological variables, possibly due to low work load as a result of missing time pressure, but subjective and performance variables clearly favoured the longer system response times. When task periods and response time-periods were analysed separately, a shift of electrodermal activity could be observed from task- to response time-periods during the course of trials in the 8s condition. This did not appear in any other condition, which points to psychophysiological excitement that develops when system response times are too long, thus providing support for the concept of optimal system response times.

Geographic and temporal validity of prediction models: Different approaches were useful to examine model performance

PubMed Central

Austin, Peter C.; van Klaveren, David; Vergouwe, Yvonne; Nieboer, Daan; Lee, Douglas S.; Steyerberg, Ewout W.

2017-01-01

Objective Validation of clinical prediction models traditionally refers to the assessment of model performance in new patients. We studied different approaches to geographic and temporal validation in the setting of multicenter data from two time periods. Study Design and Setting We illustrated different analytic methods for validation using a sample of 14,857 patients hospitalized with heart failure at 90 hospitals in two distinct time periods. Bootstrap resampling was used to assess internal validity. Meta-analytic methods were used to assess geographic transportability. Each hospital was used once as a validation sample, with the remaining hospitals used for model derivation. Hospital-specific estimates of discrimination (c-statistic) and calibration (calibration intercepts and slopes) were pooled using random effects meta-analysis methods. I2 statistics and prediction interval width quantified geographic transportability. Temporal transportability was assessed using patients from the earlier period for model derivation and patients from the later period for model validation. Results Estimates of reproducibility, pooled hospital-specific performance, and temporal transportability were on average very similar, with c-statistics of 0.75. Between-hospital variation was moderate according to I2 statistics and prediction intervals for c-statistics. Conclusion This study illustrates how performance of prediction models can be assessed in settings with multicenter data at different time periods. PMID:27262237

Effects of prolonged stress on salivary cortisol and dehydroepiandrosterone: a study of a two-week teaching practice.

PubMed

Izawa, Shuhei; Saito, Keisuke; Shirotsuki, Kentaro; Sugaya, Nagisa; Nomura, Shinobu

2012-06-01

This study investigated variations in salivary levels of cortisol and dehydroepiandrosterone (DHEA) in a prolonged stressful situation (a two-week teaching practice). Thirty-three women for whom a two-week teaching practice at a kindergarten was scheduled were asked to collect saliva samples at awakening, 30 min after awakening, and bedtime at four time points: two weeks before the practice, the first week of the practice, the second week of the practice, and a few days after the practice. In addition, they completed questionnaires for assessing perceived stress and subjective moods on each day. A linear mixed model indicated that cortisol levels significantly increased during the first and second week of the practice compared with those before and after the practice period, and that DHEA levels significantly decreased after the practice period compared with those at the other time points. Further, cortisol awakening response after the practice period significantly reduced compared with that at the other time points. Scores of perceived stress and negative moods were also higher during the practice period. This study showed that prolonged stress affected cortisol and DHEA secretion during as well as after the stress period. Copyright © 2011 Elsevier Ltd. All rights reserved.

FO Aqr time-series observations requested

NASA Astrophysics Data System (ADS)

Waagen, Elizabeth O.

2016-07-01

Dr. Colin Littlefield (University of Notre Dame) and colleagues Drs. Peter Garnavich (Notre Dame), Erin Aadland (Minnesota State), and Mark Kennedy (University College Cork) have requested AAVSO assistance in monitoring the intermediate polar cataclysmic variable FO Aqr beginning immediately. Littlefield, who with his colleagues recently published ATel #9216 and #9225, writes: "This system is in a faint state for the first time in its observational record, implying a dropoff in the mass-transfer rate. AAVSO observations contributed by Shawn Dvorak [the only observer following FO Aqr at the time] were particularly helpful in detecting this low state. Since early May, the system has recovered to V 15, but it is still well below its normal brightness. In addition, our time-series photometry shows a very strong 11.26-minute photometric period. By contrast, during its bright state, FO Aqr's light curve is dominated by a 20.9-minute period, corresponding with the spin period of the white dwarf. We interpret our observations as evidence that the system's accretion processes have changed dramatically as a result of the reduced mass-transfer rate. We have...determined that...[the 11.26-min] periodicity is dependent on the orbital phase of the binary. The 11.26-min period is dominant for about half of the orbit, but for the other half, a 22.5-min period is stronger. AAVSO observers can help us study both of these periods as well as their dependence on the orbital phase. We are particularly interested in any changes in this behavior as the system continues to brighten...Time-series photometry of FO Aqr [is requested] in order to better study the evolution of the 11.26-minute period as the system rebrightens. Unfiltered photometry reduced with a V zeropoint would be the most useful to us...A cadence of less than 60 seconds per image is important, given the brevity of these periods (especially the 11.26-min period). Finder charts with sequence may be created using the AAVSO Variable Star Plotter (https://www.aavso.org/vsp). Observations should be submitted to the AAVSO International Database. See full Alert Notice for more details.

Frequency domain system identification of helicopter rotor dynamics incorporating models with time periodic coefficients

NASA Astrophysics Data System (ADS)

Hwang, Sunghwan

1997-08-01

One of the most prominent features of helicopter rotor dynamics in forward flight is the periodic coefficients in the equations of motion introduced by the rotor rotation. The frequency response characteristics of such a linear time periodic system exhibits sideband behavior, which is not the case for linear time invariant systems. Therefore, a frequency domain identification methodology for linear systems with time periodic coefficients was developed, because the linear time invariant theory cannot account for sideband behavior. The modulated complex Fourier series was introduced to eliminate the smearing effect of Fourier series expansions of exponentially modulated periodic signals. A system identification theory was then developed using modulated complex Fourier series expansion. Correlation and spectral density functions were derived using the modulated complex Fourier series expansion for linear time periodic systems. Expressions of the identified harmonic transfer function were then formulated using the spectral density functions both with and without additive noise processes at input and/or output. A procedure was developed to identify parameters of a model to match the frequency response characteristics between measured and estimated harmonic transfer functions by minimizing an objective function defined in terms of the trace of the squared frequency response error matrix. Feasibility was demonstrated by the identification of the harmonic transfer function and parameters for helicopter rigid blade flapping dynamics in forward flight. This technique is envisioned to satisfy the needs of system identification in the rotating frame, especially in the context of individual blade control. The technique was applied to the coupled flap-lag-inflow dynamics of a rigid blade excited by an active pitch link. The linear time periodic technique results were compared with the linear time invariant technique results. Also, the effect of noise processes and initial parameter guess on the identification procedure were investigated. To study the effect of elastic modes, a rigid blade with a trailing edge flap excited by a smart actuator was selected and system parameters were successfully identified, but with some expense of computational storage and time. Conclusively, the linear time periodic technique substantially improved the identified parameter accuracy compared to the linear time invariant technique. Also, the linear time periodic technique was robust to noises and initial guess of parameters. However, an elastic mode of higher frequency relative to the system pumping frequency tends to increase the computer storage requirement and computing time.

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

Hui, C; Beddar, S; Wen, Z

Purpose: The purpose of this study is to develop a technique to obtain four-dimensional (4D) magnetic resonance (MR) images that are more representative of a patient’s typical breathing cycle by utilizing an extended acquisition time while minimizing the image artifacts. Methods: The 4D MR data were acquired with the balanced steady state free precession in two-dimensional sagittal plane of view. Each slice was acquired repeatedly for about 15 s, thereby obtaining multiple images at each of the 10 phases in the respiratory cycle. This improves the probability that at least one of the images were acquired at the desired phasemore » during a regular breathing cycle. To create optimal 4D MR images, an iterative approach was used to identify the set of images that yielded the highest slice-to-slice similarity. To assess the effectiveness of the approach, the data set was truncated into periods of 7 s (50 time points), 11 s (75 time points) and the full 15 s (100 time points). The 4D MR images were then sorted with data of the three different acquisition periods for comparison. Results: In general, the 4D MR images sorted using data from longer acquisition periods showed less mismatched artifacts. In addition, the normalized cross correlation (NCC) between slices of a 4D volume increases with increased acquisition period. The average NCC was 0.791 from the 7 s period, 0.794 from the 11 s period and 0.796 from the 15 s period. Conclusion: Our preliminary study showed that extending the acquisition time with the proposed sorting technique can improve image quality and reduce artifact presence in the 4D MR images. Data acquisition over two breathing cycles is a good trade-off between artifact reduction and scan time. This research was partially funded by the the Center for Radiation Oncology Research from UT MD Anderson Cancer Center.« less

Adult emergency department patients with sickle cell pain crisis: results from a quality improvement learning collaborative model to improve analgesic management.

PubMed

Tanabe, Paula; Hafner, John W; Martinovich, Zoran; Artz, Nicole

2012-04-01

The aims of this study were to 1) estimate differences in pain management process and patient-reported outcomes, pre- and postimplementation of analgesic protocols for adults with sickle cell disease (SCD), and 2) examine the effects of site and visit frequency on changes in pain scores and time to analgesic. A multicenter, prospective, longitudinal study enrolled patients from three academic medical centers between October 2007 and September 2009. All ED patients 18 years or older with a chief complaint of a sickle cell pain episode were enrolled. Sites formed a SCD quality improvement (QI) team and implemented standard nurse-initiated emergency department (ED) analgesic protocols; outcomes were compared between study periods defined as pre- and postimplementation of protocols. Medical record review was conducted to measure time to administration of initial analgesic, opioids used, route of opioid administration, the change in pain scores from arrival to discharge (negative numbers reflect a decrease in pain scores), and the number of ED visits per individual patient during the study period at each site. On day 7 after the ED visit, a follow-up phone interview was conducted. Patients were queried about their ED pain management using a scale from 1 to 10 (1 = outstanding, 10 = worst). Descriptive statistics are used to report the results. Ordinary least-squares regression models were constructed to measure the effect of time period, site, and number of visits per patient on change in pain score. During the study period, 342 unique patients (57% female, mean ± SD age = 32 ± 11 years) were enrolled and had a total of 2,934 visits. There was no difference in time to administration of the initial analgesic between study periods. Overall, there was a significant decrease in pain scores from arrival to discharge between the pre- and postintervention study periods: the average difference in arrival to discharge pain scores (cm) was greater during the postimplementation period than during the preintervention period (-4.1 vs. -3.6, t = 2.6, p < 0.01). Site 1 had significant improvement between study periods (mean difference = -0.87, t = 2.63, p < 0.01; F = 14.3, p < 0.01). Patients with few ED visits (one to six annual visits, mean difference = -1.55, t = 2.1, p = 0.04) and those with frequent ED visits (7 to 19 annual visits, mean difference = -1.65, t = 3.52, p < 0.01) had a significant decrease in pain scores compared to patients with very frequent ED visits (>19 visits). There was an overall decrease in the use of morphine sulfate (MS) and increase in the use of hydromorphone (χ(2) = 105.67, p < 0.001) between study periods and a significant increase in the use of oral (PO) and subcutaneous (SC) routes, with a corresponding decrease in the intravenous (IV) route (χ(2) = 13.67, p < 0.001). There were no statistically significant differences in patient-reported satisfaction with the attempt to manage pain in the ED between study periods (p = 0.54). While the use of a learning collaborative and implementation of nurse-initiated analgesic protocols was not associated with improvement in time to administration of the initial analgesic, improvements in the decrease in the arrival to discharge pain score and increased use of hydromorphone and the SC route were noted in adults with SCD in the ED. © 2012 by the Society for Academic Emergency Medicine.

Investigating light curve modulation via kernel smoothing. I. Application to 53 fundamental mode and first-overtone Cepheids in the LMC

NASA Astrophysics Data System (ADS)

Süveges, Maria; Anderson, Richard I.

2018-03-01

Context. Recent studies have revealed a hitherto unknown complexity of Cepheid pulsations by discovering irregular modulated variability using photometry, radial velocities, and interferometry. Aim. We aim to perform a statistically rigorous search and characterization of such phenomena in continuous time, applying it to 53 classical Cepheids from the OGLE-III catalog. Methods: We have used local kernel regression to search for both period and amplitude modulations simultaneously in continuous time and to investigate their detectability. We determined confidence intervals using parametric and non-parametric bootstrap sampling to estimate significance, and investigated multi-periodicity using a modified pre-whitening approach that relies on time-dependent light curve parameters. Results: We find a wide variety of period and amplitude modulations and confirm that first overtone pulsators are less stable than fundamental mode Cepheids. Significant temporal variations in period are more frequently detected than those in amplitude. We find a range of modulation intensities, suggesting that both amplitude and period modulations are ubiquitous among Cepheids. Over the 12-year baseline offered by OGLE-III, we find that period changes are often nonlinear, sometimes cyclic, suggesting physical origins beyond secular evolution. Our method detects modulations (period and amplitude) more efficiently than conventional methods that are reliant on certain features in the Fourier spectrum, and pre-whitens time series more accurately than using constant light curve parameters, removing spurious secondary peaks effectively. Conclusions: Period and amplitude modulations appear to be ubiquitous among Cepheids. Current detectability is limited by observational cadence and photometric precision: detection of amplitude modulation below 3 mmag requires space-based facilities. Recent and ongoing space missions (K2, BRITE, MOST, CoRoT) as well as upcoming ones (TESS, PLATO) will significantly improve detectability of fast modulations, such as cycle-to-cycle variations, by providing high-cadence high-precision photometry. High-quality long-term ground-based photometric time series will remain crucial to study longer-term modulations and to disentangle random fluctuations from secular evolution.

Impacts of climate changes on ocean surface gravity waves over the eastern Canadian shelf

NASA Astrophysics Data System (ADS)

Guo, Lanli; Sheng, Jinyu

2017-05-01

A numerical study is conducted to investigate the impact of climate changes on ocean surface gravity waves over the eastern Canadian shelf (ECS). The "business-as-usual" climate scenario known as Representative Concentration Pathway RCP8.5 is considered in this study. Changes in the ocean surface gravity waves over the study region for the period 1979-2100 are examined based on 3 hourly ocean waves simulated by the third-generation ocean wave model known as WAVEWATCHIII. The wave model is driven by surface winds and ice conditions produced by the Canadian Regional Climate Model (CanRCM4). The whole study period is divided into the present (1979-2008), near future (2021-2050) and far future (2071-2100) periods to quantify possible future changes of ocean waves over the ECS. In comparison with the present ocean wave conditions, the time-mean significant wave heights ( H s ) are expected to increase over most of the ECS in the near future and decrease over this region in the far future period. The time-means of the annual 5% largest H s are projected to increase over the ECS in both near and far future periods due mainly to the changes in surface winds. The future changes in the time-means of the annual 5% largest H s and 10-m wind speeds are projected to be twice as strong as the changes in annual means. An analysis of inverse wave ages suggests that the occurrence of wind seas is projected to increase over the southern Labrador and central Newfoundland Shelves in the near future period, and occurrence of swells is projected to increase over other areas of the ECS in both the near and far future periods.

Crew factors in flight operations. 8: Factors influencing sleep timing and subjective sleep quality in commercial long-haul flight crews

NASA Technical Reports Server (NTRS)

Gander, Philippa H.; Graeber, R. Curtis; Connell, Linda J.; Gregory, Kevin B.

1991-01-01

How flight crews organize their sleep during layovers on long-haul trips is documented. Additionally, environmental and physiological constraints on sleep are examined. In the trips studied, duty periods averaging 10.3 hr alternated with layovers averaging 24.8 hr, which typically included two subject-defined sleep episodes. The circadian system had a greater influence on the timing and duration of first-sleeps than second-sleeps. There was also a preference for sleeping during the local night. The time of falling asleep for second-sleeps was related primarily to the amount of sleep already obtained in the layover, and their duration depended on the amount of time remaining in the layover. For both first- and second-sleeps, sleep durations were longer when subjects fell asleep earlier with respect to the minimum of the circadian temperature cycle. Naps reported during layovers and on the flight deck may be a useful strategy for reducing cumulative sleep loss. The circadian system was not able to synchronize with the rapid series of time-zone shifts. The sleep/wake cycle was forced to adopt a period different from that of the circadian system. Flight and duty time regulations are a means of ensuring that reasonable minimum rest periods are provided. This study clearly documents that there are physiologically and environmentally determined preferred sleep times within a layover. The actual time available for sleep is thus less than the scheduled rest period.

Interdependence between crude oil and world food prices: A detrended cross correlation analysis

NASA Astrophysics Data System (ADS)

Pal, Debdatta; Mitra, Subrata K.

2018-02-01

This article explores the changing interdependence between crude oil and world food prices at varying time scales using detrended cross correlation analysis that would answer whether the interdependence (if any) differed significantly between pre and post-crisis period. Unlike the previous studies that exogenously imposed break dates for dividing the time series into sub-samples, we tested whether the mean of the crude oil price changed over time to find evidence for structural changes in the crude oil price series and endogenously determine three break dates with minimum Bayesian information criterion scores. Accordingly, we divided the entire study period in four sample periods - January 1990 to October 1999, November 1999 to February 2005, March 2005 to September 2010, and October 2010 to July 2016, where the third sample period coincided with the period of food crisis and enabled us to compare the fuel-food interdependence across pre-crisis, during the crisis, and post-crisis periods. The results of the detrended cross correlation analysis extended corroborative evidence for increasing positive interdependence between the crude oil price and world food price index along with its sub-categories, namely dairy, cereals, vegetable oil, and sugar. The article ends with the implications of these results in the domain of food policy and the financial sector.

Estimating time-varying exposure-outcome associations using case-control data: logistic and case-cohort analyses.

PubMed

Keogh, Ruth H; Mangtani, Punam; Rodrigues, Laura; Nguipdop Djomo, Patrick

2016-01-05

Traditional analyses of standard case-control studies using logistic regression do not allow estimation of time-varying associations between exposures and the outcome. We present two approaches which allow this. The motivation is a study of vaccine efficacy as a function of time since vaccination. Our first approach is to estimate time-varying exposure-outcome associations by fitting a series of logistic regressions within successive time periods, reusing controls across periods. Our second approach treats the case-control sample as a case-cohort study, with the controls forming the subcohort. In the case-cohort analysis, controls contribute information at all times they are at risk. Extensions allow left truncation, frequency matching and, using the case-cohort analysis, time-varying exposures. Simulations are used to investigate the methods. The simulation results show that both methods give correct estimates of time-varying effects of exposures using standard case-control data. Using the logistic approach there are efficiency gains by reusing controls over time and care should be taken over the definition of controls within time periods. However, using the case-cohort analysis there is no ambiguity over the definition of controls. The performance of the two analyses is very similar when controls are used most efficiently under the logistic approach. Using our methods, case-control studies can be used to estimate time-varying exposure-outcome associations where they may not previously have been considered. The case-cohort analysis has several advantages, including that it allows estimation of time-varying associations as a continuous function of time, while the logistic regression approach is restricted to assuming a step function form for the time-varying association.

A cephalometric study of skulls from the Bahriyah oasis

PubMed Central

Zaki, Moushira Erfan; Soliman, Muhammad Al-Tohamy; El-Bassyouni, Hala T.

2012-01-01

Objectives: To determine the craniofacial characteristics of crania from the Bahariyah oasis dating from the Greco-Roman period and to compare their cephalometric traits with other ancient Egyptian samples from various time periods and to evaluate sexual dimorphism. Materials and Methods: The sample comprised 149 skulls (90 males and 59 females), belonging to the Greco-Roman (332 B.C. – 395 A.D.). Lateral and postero-anterior cephalograms were taken. Sixteen linear measurements were analyzed and six indices were calculated. Results: Significant differences were found between males and females almost in all measurements. All male measurements were greater than those of the females. The study shows notable differences in the craniofacial parameters of the present sample as compared to other ancient Egyptians from various periods and from various geographical areas. Conclusion: The present study suggests that the studied crania from Bahriyah oasis had a specific craniometric phenotype, which is distinguished from other Egyptian samples from different periods, suggesting some migration could have occurred along the Egyptian Nile Valley over various times. PMID:23741149

The correlation between infectivity and incubation period of measles, estimated from households with two cases.

PubMed

Klinkenberg, Don; Nishiura, Hiroshi

2011-09-07

The generation time of an infectious disease is the time between infection of a primary case and infection of a secondary case by the primary case. Its distribution plays a key role in understanding the dynamics of infectious diseases in populations, e.g. in estimating the basic reproduction number. Moreover, the generation time and incubation period distributions together characterize the effectiveness of control by isolation and quarantine. In modelling studies, a relation between the two is often not made specific, but a correlation is biologically plausible. However, it is difficult to establish such correlation, because of the unobservable nature of infection events. We have quantified a joint distribution of generation time and incubation period by a novel estimation method for household data with two susceptible individuals, consisting of time intervals between disease onsets of two measles cases. We used two such datasets, and a separate incubation period dataset. Results indicate that the mean incubation period and the generation time of measles are positively correlated, and that both lie in the range of 11-12 days, suggesting that infectiousness of measles cases increases significantly around the time of symptom onset. The correlation between times from infection to secondary transmission and to symptom onset could critically affect the predicted effectiveness of isolation and quarantine. Copyright © 2011 Elsevier Ltd. All rights reserved.

Effectiveness of a novel and scalable clinical decision support intervention to improve venous thromboembolism prophylaxis: a quasi-experimental study.

PubMed

Umscheid, Craig A; Hanish, Asaf; Chittams, Jesse; Weiner, Mark G; Hecht, Todd E H

2012-08-31

Venous thromboembolism (VTE) causes morbidity and mortality in hospitalized patients, and regulators and payors are encouraging the use of systems to prevent them. Here, we examine the effect of a computerized clinical decision support (CDS) intervention implemented across a multi-hospital academic health system on VTE prophylaxis and events. The study included 223,062 inpatients admitted between April 2007 and May 2010, and used administrative and clinical data. The intervention was integrated into a commercial electronic health record (EHR) in an admission orderset used for all admissions. Three time periods were examined: baseline (period 1), and the time after implementation of the first CDS intervention (period 2) and a second iteration (period 3). Providers were prompted to accept or decline prophylaxis based on patient risk. Time series analyses examined the impact of the intervention on VTE prophylaxis during time periods two and three compared to baseline, and a simple pre-post design examined impact on VTE events and bleeds secondary to anticoagulation. VTE prophylaxis and events were also examined in a prespecified surgical subset of our population meeting the public reporting criteria defined by the Agency for Healthcare Research and Quality (AHRQ) Patient Safety Indicator (PSI). Unadjusted analyses suggested that "recommended", "any", and "pharmacologic" prophylaxis increased from baseline to the last study period (27.1% to 51.9%, 56.7% to 78.1%, and 42.0% to 54.4% respectively; p < 0.01 for all comparisons). Results were significant across all hospitals and the health system overall. Interrupted time series analyses suggested that our intervention increased the use of "recommended" and "any" prophylaxis by 7.9% and 9.6% respectively from baseline to time period 2 (p < 0.01 for both comparisons); and 6.6% and 9.6% respectively from baseline to the combined time periods 2 and 3 (p < 0.01 for both comparisons). There were no significant changes in "pharmacologic" prophylaxis in the adjusted model. The overall percent of patients with VTE increased from baseline to the last study period (2.0% to 2.2%; p = 0.03), but an analysis excluding patients with VTE "present on admission" (POA) demonstrated no difference in events (1.3% to 1.3%; p = 0.80). Overall bleeds did not significantly change. An analysis examining VTE prophylaxis and events in a surgical subset of patients defined by the AHRQ PSI demonstrated increased "recommended", "any", and "pharmacologic" prophylaxis from baseline to the last study period (32.3% to 60.0%, 62.8% to 85.7%, and 47.9% to 63.3% respectively; p < 0.01 for all comparisons) as well as reduced VTE events (2.2% to 1.7%; p < 0.01). The CDS intervention was associated with an increase in "recommended" and "any" VTE prophylaxis across the multi-hospital academic health system. The intervention was also associated with increased VTE rates in the overall study population, but a subanalysis using only admissions with appropriate POA documentation suggested no change in VTE rates, and a prespecified analysis of a surgical subset of our sample as defined by the AHRQ PSI for public reporting purposes suggested reduced VTE. This intervention was created in a commonly used commercial EHR and is scalable across institutions with similar systems.

Effectiveness of a novel and scalable clinical decision support intervention to improve venous thromboembolism prophylaxis: a quasi-experimental study

PubMed Central

2012-01-01

Background Venous thromboembolism (VTE) causes morbidity and mortality in hospitalized patients, and regulators and payors are encouraging the use of systems to prevent them. Here, we examine the effect of a computerized clinical decision support (CDS) intervention implemented across a multi-hospital academic health system on VTE prophylaxis and events. Methods The study included 223,062 inpatients admitted between April 2007 and May 2010, and used administrative and clinical data. The intervention was integrated into a commercial electronic health record (EHR) in an admission orderset used for all admissions. Three time periods were examined: baseline (period 1), and the time after implementation of the first CDS intervention (period 2) and a second iteration (period 3). Providers were prompted to accept or decline prophylaxis based on patient risk. Time series analyses examined the impact of the intervention on VTE prophylaxis during time periods two and three compared to baseline, and a simple pre-post design examined impact on VTE events and bleeds secondary to anticoagulation. VTE prophylaxis and events were also examined in a prespecified surgical subset of our population meeting the public reporting criteria defined by the Agency for Healthcare Research and Quality (AHRQ) Patient Safety Indicator (PSI). Results Unadjusted analyses suggested that “recommended”, “any”, and “pharmacologic” prophylaxis increased from baseline to the last study period (27.1% to 51.9%, 56.7% to 78.1%, and 42.0% to 54.4% respectively; p < 0.01 for all comparisons). Results were significant across all hospitals and the health system overall. Interrupted time series analyses suggested that our intervention increased the use of “recommended” and “any” prophylaxis by 7.9% and 9.6% respectively from baseline to time period 2 (p < 0.01 for both comparisons); and 6.6% and 9.6% respectively from baseline to the combined time periods 2 and 3 (p < 0.01 for both comparisons). There were no significant changes in “pharmacologic” prophylaxis in the adjusted model. The overall percent of patients with VTE increased from baseline to the last study period (2.0% to 2.2%; p = 0.03), but an analysis excluding patients with VTE “present on admission” (POA) demonstrated no difference in events (1.3% to 1.3%; p = 0.80). Overall bleeds did not significantly change. An analysis examining VTE prophylaxis and events in a surgical subset of patients defined by the AHRQ PSI demonstrated increased “recommended”, “any”, and “pharmacologic” prophylaxis from baseline to the last study period (32.3% to 60.0%, 62.8% to 85.7%, and 47.9% to 63.3% respectively; p < 0.01 for all comparisons) as well as reduced VTE events (2.2% to 1.7%; p < 0.01). Conclusions The CDS intervention was associated with an increase in “recommended” and “any” VTE prophylaxis across the multi-hospital academic health system. The intervention was also associated with increased VTE rates in the overall study population, but a subanalysis using only admissions with appropriate POA documentation suggested no change in VTE rates, and a prespecified analysis of a surgical subset of our sample as defined by the AHRQ PSI for public reporting purposes suggested reduced VTE. This intervention was created in a commonly used commercial EHR and is scalable across institutions with similar systems. PMID:22938083

Inferring time-varying recharge from inverse analysis of long-term water levels

NASA Astrophysics Data System (ADS)

Dickinson, Jesse E.; Hanson, R. T.; Ferré, T. P. A.; Leake, S. A.

2004-07-01

Water levels in aquifers typically vary in response to time-varying rates of recharge, suggesting the possibility of inferring time-varying recharge rates on the basis of long-term water level records. Presumably, in the southwestern United States (Arizona, Nevada, New Mexico, southern California, and southern Utah), rates of mountain front recharge to alluvial aquifers depend on variations in precipitation rates due to known climate cycles such as the El Niño-Southern Oscillation index and the Pacific Decadal Oscillation. This investigation examined the inverse application of a one-dimensional analytical model for periodic flow described by Lloyd R. Townley in 1995 to estimate periodic recharge variations on the basis of variations in long-term water level records using southwest aquifers as the case study. Time-varying water level records at various locations along the flow line were obtained by simulation of forward models of synthetic basins with applied sinusoidal recharge of either a single period or composite of multiple periods of length similar to known climate cycles. Periodic water level components, reconstructed using singular spectrum analysis (SSA), were used to calibrate the analytical model to estimate each recharge component. The results demonstrated that periodic recharge estimates were most accurate in basins with nearly uniform transmissivity and the accuracy of the recharge estimates depends on monitoring well location. A case study of the San Pedro Basin, Arizona, is presented as an example of calibrating the analytical model to real data.

Studies of the Long Secondary Periods in Pulsating Red Giants

NASA Astrophysics Data System (ADS)

Percy, J. R.; Deibert, E.

2016-12-01

We have used systematic, sustained visual observations from the AAVSO International Database and the AAVSO time-series analysis package VSTAR to study the unexplained "long secondary periods" (LSPs) in 27 pulsating red giants. In our sample, the LSPs range from 479 to 2967 days, and are on average 8.1 +/- 1.3 times the excited pulsation period. There is no evidence for more than one LSP in each star. In stars with both the fundamental and first overtone radial period present, the LSP is more often about 10 times the latter. The visual amplitudes of the LSPs are typically 0.1 magnitude and do not correlate with the LSP. The phase curves tend to be sinusoidal, but at least two are sawtooth. The LSPs are stable, within their errors, over the timespan of our data, which is typically 25,000 days. The amplitudes, however, vary by up to a factor of two or more on a time scale of roughly 20-30 LSPs. There is no obvious difference between the carbon (C) stars and the normal oxygen (M) stars. Previous multicolor observations showed that the LSP color variations are similar to those of the pulsation period, and of the LSPs in the Magellanic Clouds, and not like those of eclipsing stars. We note that the LSPs are similar to the estimated rotation periods of the stars, though the latter have large uncertainties. This suggests that the LSP phenomenon may be a form of modulated rotational variability.

24 CFR 58.21 - Time periods.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Time periods. 58.21 Section 58.21...: Environmental Review Procedures § 58.21 Time periods. All time periods in this part shall be counted in calendar days. The first day of a time period begins at 12:01 a.m. local time on the day following the...

24 CFR 58.21 - Time periods.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 24 Housing and Urban Development 1 2014-04-01 2014-04-01 false Time periods. 58.21 Section 58.21...: Environmental Review Procedures § 58.21 Time periods. All time periods in this part shall be counted in calendar days. The first day of a time period begins at 12:01 a.m. local time on the day following the...

24 CFR 58.21 - Time periods.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 24 Housing and Urban Development 1 2011-04-01 2011-04-01 false Time periods. 58.21 Section 58.21...: Environmental Review Procedures § 58.21 Time periods. All time periods in this part shall be counted in calendar days. The first day of a time period begins at 12:01 a.m. local time on the day following the...

24 CFR 58.21 - Time periods.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 24 Housing and Urban Development 1 2013-04-01 2013-04-01 false Time periods. 58.21 Section 58.21...: Environmental Review Procedures § 58.21 Time periods. All time periods in this part shall be counted in calendar days. The first day of a time period begins at 12:01 a.m. local time on the day following the...

24 CFR 58.21 - Time periods.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 24 Housing and Urban Development 1 2012-04-01 2012-04-01 false Time periods. 58.21 Section 58.21...: Environmental Review Procedures § 58.21 Time periods. All time periods in this part shall be counted in calendar days. The first day of a time period begins at 12:01 a.m. local time on the day following the...

Rank One Strange Attractors in Periodically Kicked Predator-Prey System with Time-Delay

NASA Astrophysics Data System (ADS)

Yang, Wenjie; Lin, Yiping; Dai, Yunxian; Zhao, Huitao

2016-06-01

This paper is devoted to the study of the problem of rank one strange attractor in a periodically kicked predator-prey system with time-delay. Our discussion is based on the theory of rank one maps formulated by Wang and Young. Firstly, we develop the rank one chaotic theory to delayed systems. It is shown that strange attractors occur when the delayed system undergoes a Hopf bifurcation and encounters an external periodic force. Then we use the theory to the periodically kicked predator-prey system with delay, deriving the conditions for Hopf bifurcation and rank one chaos along with the results of numerical simulations.

A comparison of estimators from self-controlled case series, case-crossover design, and sequence symmetry analysis for pharmacoepidemiological studies.

PubMed

Takeuchi, Yoshinori; Shinozaki, Tomohiro; Matsuyama, Yutaka

2018-01-08

Despite the frequent use of self-controlled methods in pharmacoepidemiological studies, the factors that may bias the estimates from these methods have not been adequately compared in real-world settings. Here, we comparatively examined the impact of a time-varying confounder and its interactions with time-invariant confounders, time trends in exposures and events, restrictions, and misspecification of risk period durations on the estimators from three self-controlled methods. This study analyzed self-controlled case series (SCCS), case-crossover (CCO) design, and sequence symmetry analysis (SSA) using simulated and actual electronic medical records datasets. We evaluated the performance of the three self-controlled methods in simulated cohorts for the following scenarios: 1) time-invariant confounding with interactions between the confounders, 2) time-invariant and time-varying confounding without interactions, 3) time-invariant and time-varying confounding with interactions among the confounders, 4) time trends in exposures and events, 5) restricted follow-up time based on event occurrence, and 6) patient restriction based on event history. The sensitivity of the estimators to misspecified risk period durations was also evaluated. As a case study, we applied these methods to evaluate the risk of macrolides on liver injury using electronic medical records. In the simulation analysis, time-varying confounding produced bias in the SCCS and CCO design estimates, which aggravated in the presence of interactions between the time-invariant and time-varying confounders. The SCCS estimates were biased by time trends in both exposures and events. Erroneously short risk periods introduced bias to the CCO design estimate, whereas erroneously long risk periods introduced bias to the estimates of all three methods. Restricting the follow-up time led to severe bias in the SSA estimates. The SCCS estimates were sensitive to patient restriction. The case study showed that although macrolide use was significantly associated with increased liver injury occurrence in all methods, the value of the estimates varied. The estimations of the three self-controlled methods depended on various underlying assumptions, and the violation of these assumptions may cause non-negligible bias in the resulting estimates. Pharmacoepidemiologists should select the appropriate self-controlled method based on how well the relevant key assumptions are satisfied with respect to the available data.

Inference on periodicity of circadian time series.

PubMed

Costa, Maria J; Finkenstädt, Bärbel; Roche, Véronique; Lévi, Francis; Gould, Peter D; Foreman, Julia; Halliday, Karen; Hall, Anthony; Rand, David A

2013-09-01

Estimation of the period length of time-course data from cyclical biological processes, such as those driven by the circadian pacemaker, is crucial for inferring the properties of the biological clock found in many living organisms. We propose a methodology for period estimation based on spectrum resampling (SR) techniques. Simulation studies show that SR is superior and more robust to non-sinusoidal and noisy cycles than a currently used routine based on Fourier approximations. In addition, a simple fit to the oscillations using linear least squares is available, together with a non-parametric test for detecting changes in period length which allows for period estimates with different variances, as frequently encountered in practice. The proposed methods are motivated by and applied to various data examples from chronobiology.

Circadian occurrence of variceal bleeding in patients with liver cirrhosis.

PubMed

Siringo, S; Bolondi, L; Sofia, S; Hermida, R C; Gramantieri, L; Gaiani, S; Piscaglia, F; Carbone, C; Misitano, B; Corinaldesi, R

1996-12-01

Several clinical events have a rhythmicity over the 24 h period. We assessed the presence of periodic rhythm in the occurrence of haematemesis in patients with liver cirrhosis under different daylight regimens, namely during standard time and during daylight savings. Over a 48 month period there were 212 consecutive admissions of 118 cirrhotics with variceal bleeding. Complete data were available for 181 episodes of bleeding: 121 (66.9%) started with haematemesis and 60 (33.1%) started with melaena. One hundred and two (56%) episodes occurred during daylight savings and 79 (44%) occurred during standard time. The cosinor test showed a 24 h biphasic peak for the occurrence of haematemesis (09.45 and 21.45 h). Moreover, a biphasic diurnal asymmetric frequency was also found by multiple component rhythmometry. The time peaks of onset of variceal haemorrhage did not change significantly during standard time and daylight savings. Patients with more than one haematemesis episode significantly bled over the same time interval. The present study confirms that over the 24 h period variceal bleeding in cirrhotic patients occurs with a predictable rhythmicity that does not seem to be under the control of the light-dark cycle. The finding of a chronorisk for variceal haemorrhage addresses specific questions for pathophysiological studies as well as for new treatment strategies.

MEM spectral analysis for predicting influenza epidemics in Japan.

PubMed

Sumi, Ayako; Kamo, Ken-ichi

2012-03-01

The prediction of influenza epidemics has long been the focus of attention in epidemiology and mathematical biology. In this study, we tested whether time series analysis was useful for predicting the incidence of influenza in Japan. The method of time series analysis we used consists of spectral analysis based on the maximum entropy method (MEM) in the frequency domain and the nonlinear least squares method in the time domain. Using this time series analysis, we analyzed the incidence data of influenza in Japan from January 1948 to December 1998; these data are unique in that they covered the periods of pandemics in Japan in 1957, 1968, and 1977. On the basis of the MEM spectral analysis, we identified the periodic modes explaining the underlying variations of the incidence data. The optimum least squares fitting (LSF) curve calculated with the periodic modes reproduced the underlying variation of the incidence data. An extension of the LSF curve could be used to predict the incidence of influenza quantitatively. Our study suggested that MEM spectral analysis would allow us to model temporal variations of influenza epidemics with multiple periodic modes much more effectively than by using the method of conventional time series analysis, which has been used previously to investigate the behavior of temporal variations in influenza data.

Study of Basin Recession Characteristics and Groundwater Storage Properties

NASA Astrophysics Data System (ADS)

Yen-Bo, Chen; Cheng-Haw, Lee

2017-04-01

Stream flow and groundwater storage are freshwater resources that human live on.In this study, we discuss southern area basin recession characteristics and Kao-Ping River basin groundwater storage, and hope to supply reference to Taiwan water resource management. The first part of this study is about recession characteristics. We apply Brutsaert (2008) low flow analysis model to establish two recession data pieces sifting models, including low flow steady period model and normal condition model. Within individual event analysis, group event analysis and southern area basin recession assessment, stream flow and base flow recession characteristics are parameterized. The second part of this study is about groundwater storage. Among main basin in southern Taiwan, there are sufficient stream flow and precipitation gaging station data about Kao-Ping River basin and extensive drainage data, and data about different hydrological characteristics between upstream and downstream area. Therefore, this study focuses on Kao-Ping River basin and accesses groundwater storage properties. Taking residue of groundwater volume in dry season into consideration, we use base flow hydrograph to access periodical property of groundwater storage, in order to establish hydrological period conceptual model. With groundwater storage and precipitation accumulative linearity quantified by hydrological period conceptual model, their periodical changing and alternation trend properties in each drainage areas of Kao-Ping River basin have been estimated. Results of this study showed that the recession time of stream flow is related to initial flow rate of the recession events. The recession time index is lower when the flow is stream flow, not base flow, and the recession time index is higher in low flow steady flow period than in normal recession condition. By applying hydrological period conceptual model, groundwater storage could explicitly be analyzed and compared with precipitation, by only using stream flow data. Keywords: stream flow, base flow, recession characteristics, groundwater storage

Associations of herd- and cow-level factors, cow lying behavior, and risk of elevated somatic cell count in free-stall housed lactating dairy cows.

PubMed

Watters, M E Alexandrea; Meijer, Karin M A; Barkema, Herman W; Leslie, Kenneth E; von Keyserlingk, Marina A G; Devries, Trevor J

2013-09-01

Recent evidence suggests that the risk of intramammary infection in dairy cows is related to lying patterns. The objectives of this study were to quantify the standing and lying behavior of dairy cows milked 3×/d, determine the cow- and herd-level factors associated with these behaviors, and relate these findings to the risk of an elevated somatic cell count (SCC). Five commercial free-stall dairy herds in Eastern Ontario, milking 3×/d, were enrolled in a longitudinal study. Forty Holstein-Friesian cows/herd were randomly selected as focal animals based on days in milk (<200 d) and SCC (<100,000 cells/mL). Farms were followed for 4, 5-week periods. Individual-cow SCC was recorded at the beginning of each period and end of the final period. Elevated SCC (eSCC) was used as an indicator of subclinical mastitis. A new incident eSCC was defined as an individual cow that started the period with a SCC <100,000 cells/mL but whose next SCC exceeded 200,000 cells/mL. Lying behavior was recorded 5d after each milk sampling using data loggers. For these 5d, individual milking times and feeding times were also recorded. On d1 of each recording period 2 trained observers scored focal cows for hygiene and lameness. Throughout the course of the study, cows averaged 11.2h/d of lying time, split into 8.6 lying bouts/d that were on average 84.6 min in length. Later lactation cows had longer daily lying times that were split into fewer lying bouts of longer duration than cows earlier in lactation. Lame cows had longer daily lying times and lying bout durations than non-lame cows. Cows with greater milk yield had lower lying times than lower producing cows. Average post-milking standing time across the study herds was 103 min. Manipulation of feed (feed delivery or push-up) by the stockperson, in the hour before milking or shortly thereafter, resulted in the longest post-milking standing times. Over the study period, 48 new eSCC were detected, resulting in a mean herd incidence rate of 0.91 eSCC/cow-year at risk for all study herds. A non-linear relationship between post-milking standing time and eSCC incidence was found; compared to those cows that lie down <90 min after milking, cows that lie down for the first time >90 min after milking had a lower risk of acquiring a new eSCC. The risk of experiencing an eSCC was also increased in multiparous cows, and in those cows with a higher SCC at the beginning of the study. These results indicate that management practices that promote post-milking standing time, such as the manipulation of feed delivery around milking times, should be encouraged to reduce the risk of cows experiencing new eSCC. Copyright © 2013 Elsevier B.V. All rights reserved.

Variability of Stimulant Levels in Nine Sports Supplements Over a 9-Month Period.

PubMed

Attipoe, Selasi; Cohen, Pieter A; Eichner, Amy; Deuster, Patricia A

2016-10-01

Many studies have found that some dietary supplement product labels do not accurately reflect the actual ingredients. However, studies have not been performed to determine if ingredients in the same dietary supplement product vary over time. The objective of this study was to assess the consistency of stimulant ingredients in popular sports supplements sold in the United States over a 9-month period. Three samples of nine popular sports supplements were purchased over the 9-month period. The 27 samples were analyzed for caffeine and several other stimulants (including adulterants). The identity and quantity of stimulants were compared with stimulants listed on the label and stimulants found at earlier time points to determine the variability in individual products over the 9-month period. The primary outcome measure was the variability of stimulant amounts in the products examined. Many supplements did not contain the same number and quantity of stimulants at all time points over the 9-month period. Caffeine content varied widely in five of the six caffeinated supplements compared with the initial measurement (-7% to +266%). In addition, the stimulants-synephrine, octopamine, cathine, ephedrine, pseudoephedrine, strychnine, and methylephedrine-occurred in variable amounts in eight of the nine products. The significance of these findings is uncertain: the sample size was insufficient to support statistical analysis. In our sample of nine popular sports supplements, the presence and quantity of stimulants varied over a 9-month period. However, future studies are warranted to determine if the variability found is significant and generalizable to other supplements.

What is the best?: simple versus visitor restricted rest period.

PubMed

Silvius-Byron, Stephanie A; Florimonte, Christine; Panganiban, Elizabeth G; Ulmer, Janice Fitzgerald

2014-05-01

The aim of this study was to compare a highly structured planned rest protocol that includes visitor and healthcare personnel restrictions with a simple planned rest period that encourages patients to rest during a designated time without restriction of visitors and healthcare personnel. Many hospitals acute care have begun to restrict visitors and nonessential health team interventions during specific times despite the lack of experimentally designed studies. Using a convenience sample of 52 intermediate care unit patients, a randomized experimental design study compared a highly structured planned rest protocol with restriction of visitors/healthcare personnel to a simple planned rest period without restrictions. The primary outcome variable was the patient's perceived quality of rest after a 2-hour rest period. Intermediate care patients' perception of rest and sleep during a designated rest period was similar whether elaborate rest strategies were used, including visitor and healthcare personnel restrictions, or if it was only suggested they rest and the door to their room closed. The restriction of visitors and healthcare personnel during a 2-hour rest period did not improve the patient's perception of rest or how long it took them to go to sleep.

Survival period after tube feeding in bedridden older patients.

PubMed

Kosaka, Yoichi; Nakagawa-Satoh, Takuma; Ohrui, Takashi; Fujii, Masahiko; Arai, Hiroyuki; Sasaki, Hidetada

2012-04-01

We prospectively studied survival periods after tube feeding. Participants were 163 bedridden older patients suffering from dysphagia. A wide range of survival periods after tube feeding were observed within half a year without tube feeding after being bedridden. After this initial period, survival periods after tube feeding were limited to approximately half a year. Survival periods after tube feeding were positively proportional to the length of time patients were free from pneumonia after tube feeding. After tube feeding, patients died from pneumonia within half a year, and the frequency of pneumonia was 3.1 ± 2.7 times (mean ± SD) before death. Survival periods after tube feeding for less than 1 year were primarily determined by being bedridden for more than half a year without tube feeding and once pneumonia occurred; patients who were tube fed did not survive for more than half a year. © 2012 Japan Geriatrics Society.

Time trends in upper gastrointestinal diseases and Helicobacter pylori infection in a multiracial Asian population--a 20-year experience over three time periods.

PubMed

Leow, A H-R; Lim, Y-Y; Liew, W-C; Goh, K-L

2016-04-01

Marked epidemiological changes in upper gastrointestinal diseases and Helicobacter pylori infection have taken place in the Asian Pacific region. In particular, differences with respect to race in the multiracial Asian population in Malaysia have been important and interesting. A time trend study of upper gastrointestinal disease and H. pylori infection in three time periods: 1989-1990, 1999-2000 and 2009-2010 spanning a period of 20 years was carried out. Consecutive first time gastroscopies carried out on patients attending the University of Malaya Medical Center were studied. Diagnoses and H. pylori infection status were carefully recorded. A steady decline in prevalence of duodenal ulcer (DU) and gastric ulcer (GU) from 21.1% to 9.5% to 5.0% and from 11.9% to 9.4% to 9.9% while an increase in erosive oesophagitis (EO) from 2.0% to 8.4% to 9.5% (chi-square for trend; P < 0.001) for the periods 1989-1990, 1999-200 and 2009-2010 were observed. The overall prevalence of H. pylori had also decreased from 51.7% to 30.3% to 11.1% for the same periods of time. The proportion of H. pylori positive ulcers had also decreased: DU (90.1%-69.8%-28.9%) and GU (86.6-56.8%-18.9%) (P < 0.001). This was observed in Malays, Chinese and Indians but the difference over time was most marked in Malays. There was a steady decline in the proportion of patients with gastric and oesophageal cancers. Peptic ulcers have declined significantly over a 20-year period together with a decline in H. pylori infection. In contrast, a steady increase in erosive oesophagitis was observed. Gastric and oesophageal squamous cell cancers have declined to low levels. © 2016 John Wiley & Sons Ltd.

Time trends in the association of ESRD incidence with area-level poverty in the US population.

PubMed

Garrity, Bridget H; Kramer, Holly; Vellanki, Kavitha; Leehey, David; Brown, Julia; Shoham, David A

2016-01-01

The objective of this study was to examine the temporal trends of the association between area-level poverty status and end-stage renal disease (ESRD) incidence. We hypothesized that the association between area-level poverty status and ESRD incidence has increased significantly over time. Patient data from the United States Renal Data System were linked with data from the 2000 and 2010 US census. Area-level poverty was defined as living in a zip code-defined area with ≥20% of households living below the federal poverty line. Negative binomial regression models were created to examine the association between area-level poverty status and ESRD incidence by time period in the US adult population while simultaneously adjusting for the distribution of age, sex, and race/ethnicity within a zip code. Time was categorized as January 1, 1995 through December 31, 2004 (Period 1) and January 1, 2005 through December 31, 2010 (Period 2). The percentage of adults initiating dialysis with area-level poverty increased from 27.4% during Period 1 to 34.0% in Period 2. After accounting for the distribution of age, sex, and race/ethnicity within a zip code, area-level poverty status was associated with a 1.24 (95% confidence interval [CI] 1.22, 1.25)-fold higher ESRD incidence. However, this association differed by time period with 1.04-fold (95% CI 1.02, 1.05) higher ESRD incidence associated with poverty status for Period 2 compared with the association between ESRD and poverty status in Period 1. Area-level poverty and its association with ESRD incidence is not static over time. © 2015 International Society for Hemodialysis.

Diel periodicity and chronology of upstream migration in yellow-phase American eels (Anguilla rostrata)

USGS Publications Warehouse

Aldinger, Joni L.; Welsh, Stuart A.

2017-01-01

Yellow-phase American eel (Anguilla rostrata) upstream migration is temporally punctuated, yet migration chronology within diel time periods is not well-understood. This study examined diel periodicity, chronology, and total length (TL) of six multi-day, high-count (285–1,868 eels) passage events of upstream migrant yellow-phase American eels at the Millville Dam eel ladder, lower Shenandoah River, West Virginia during 2011–2014. We categorized passage by diel periods (vespertine, nocturnal, matutinal, diurnal) and season (spring, summer, late summer/early fall, fall). We depicted passage counts as time-series histograms and used time-series spectral analysis (Fast Fourier Transformation) to identify cyclical patterns and diel periodicity of upstream migration. We created histograms to examine movement patterns within diel periods for each passage event and fit normal mixture models (2–9 mixtures) to describe multiple peaks of passage counts. Periodicity of movements for each passage event followed a 24-h activity cycle with mostly nocturnal movement. Multimodal models were supported by the data; most modes represented nocturnal movements, but modes at or near the transition between twilight and night were also common. We used mixed-model methodology to examine relationships among TL, diel period, and season. An additive-effects model of diel period + season was the best approximating model. A decreasing trend of mean TL occurred across diel movement periods, with the highest mean TL occurring during fall relative to similar mean values of TL for spring, summer, and late summer/early fall. This study increased our understanding of yellow-phase American eels by demonstrating the non-random nature of their upstream migration.

Measurement Units. Intercultural Educational Activities

ERIC Educational Resources Information Center

Magdas, Ioana

2009-01-01

Today's society is characterized by a plurality of cultures in such a way that a person will often interact and interrelate with new cultures. The situation becomes even more complicated when one has to adapt to a new culture for a short period of time (travel or study visit) or a long period of time (new work place, emigration etc.). Any…

Anti-control of chaos of single time-scale brushless DC motor.

PubMed

Ge, Zheng-Ming; Chang, Ching-Ming; Chen, Yen-Sheng

2006-09-15

Anti-control of chaos of single time-scale brushless DC motors is studied in this paper. In order to analyse a variety of periodic and chaotic phenomena, we employ several numerical techniques such as phase portraits, bifurcation diagrams and Lyapunov exponents. Anti-control of chaos can be achieved by adding an external constant term or an external periodic term.

Physical Activity in High School during "Free-Time" Periods

ERIC Educational Resources Information Center

Silva, Pedro; Sousa, Michael; Sá, Carla; Ribeiro, José; Mota, Jorge

2015-01-01

The purpose of this study was to examine youth physical activity (PA) in free-time periods during high school days and their contribution to total PA. Differences in terms of sex, age, body mass index and school level were assessed in a sample of Portuguese adolescents. Participants totalled 213 (135 girls), aged 14.6 ± 1.7, from two different…

Role of observation of live cases done by Japanese experts in the acquisition of ESD skills by a western endoscopist.

PubMed

Draganov, Peter V; Chang, Myron; Coman, Roxana M; Wagh, Mihir S; An, Qi; Gotoda, Takuji

2014-04-28

To evaluate the role of observation of experts performing endoscopic submucosal dissection (ESD) in the acquisition of ESD skills. This prospective study is documenting the learning curve of one Western endoscopist. The study consisted of three periods. In the first period (pre-observation), the trainee performed ESDs in animal models in his home institution in the United States. The second period (observation) consisted of visit to Japan and observation of live ESD cases done by experts. The observation of cases occurred over a 5-wk period. During the third period (post-observation), the trainee performed ESD in animal models in a similar fashion as in the first period. Three animal models were used: live 40-50 kg Yorkshire pig, explanted pig stomach model, and explanted pig rectum model. The outcomes from the ESDs done in the animal models before and after observation of live human cases (main study intervention) were compared. Statistical analysis of the data included: Fisher's exact test to compare distributions of a categorical variable, Wilcoxon rank sum test to compare distributions of a continuous variable between the two groups (pre-observation and post-observation), and Kruskal-Wallis test to evaluate the impact of lesion location and type of model (ex-vivo vs live pig) on lesion removal time. The trainee performed 38 ESDs in animal model (29 pre-observation/9 post-observation). The removal times post-observation were significantly shorter than those pre-observation (32.7 ± 15.0 min vs 63.5 ± 9.8 min, P < 0.001). To minimize the impact of improving physician skill, the 9 lesions post-observation were compared to the last 9 lesions pre-observation and the removal times remained significantly shorter (32.7 ± 15.0 min vs 61.0 ± 7.4 min, P = 0.0011). Regression analysis showed that ESD observation significantly reduced removal time when controlling for the sequence of lesion removal (P = 0.025). Furthermore, it was also noted a trend towards decrease in failure to remove lesions and decrease in complications after the period of observation. This study did not find a significant difference in the time needed to remove lesions in different animal models. This finding could have important implications in designing training programs due to the substantial difference in cost between live animal and explanted organ models. The main limitation of this study is that it reflects the experience of a single endoscopist. Observation of experts performing ESD over short period of time can significantly contribute to the acquisition of ESD skills.

Hospital union election activity, 1974-85

PubMed Central

Becker, Edmund R.; Rakich, Jonathon S.

1988-01-01

This study, using National Labor Relations Board data and American Hospital Association data, reports on the status of union election activity in the hospital industry for a 65-month period, January 1980-May 1985, and contrasts it with earlier data for a similar 65-month time period (1974-79). Together these data provide a comprehensive overview of union election activity in non-Federal, nongovernment hospitals since the passage of the 1974 Nonprofit Hospital Amendments to the Taft-Hartley Act. The study analyzes union, election, hospital, and environmental characteristics. Comparisons over the two time periods show that, while union victory rates in hospital elections have remained constant, the total number of elections has declined dramatically in the hospital industry. PMID:10312518

A tale of two cities: the effect of extended drinking hours in licensed establishments on impaired driving and assault charges.

PubMed

Vingilis, Evelyn; Mcleod, A Ian; Mann, Robert E; Seeley, Jane

2008-12-01

On May 1, 1996, Ontario, Canada, amended the Liquor Licence Act to extend the hours of alcohol sales and service in licensed establishments from 1 to 2 a.m. The purpose of this study was to examine the effect of extended drinking hours on two cities in southwestern Ontario, Canada, one of which (London) would be affected by the alcohol control policy of extended drinking hours and the second city (Windsor) would be affected by two alcohol policies, extended drinking hours, and cross-border legal drinking age differences between Ontario and Michigan. Specifically, this study tested whether there were differences in impaired driving and assault charges in London and Windsor, Ontario, concomitant with the extended drinking hour amendment. A quasi-experimental design using interrupted time series was used to assess changes. The analyzed data sets were monthly police impaired driving and assault charges data for Ontario, for the 11-12 p.m., 12-1 a.m., 1-2 a.m., 2-3 a.m. and 3-4 a.m. time windows, for 4 years pre- and 3 years post-policy change. Overall, London and Windsor exhibited significant overall reductions in impaired driving charges and no changes for assault charges aggregated over the 11 p.m.-4 a.m. time period after the drinking hours were extended. Within the different time windows, London showed significant decreases for the 1-2 a.m. Sunday-Wednesday and Thursday-Sunday time periods and a significant increase for the Sunday-Wednesday 3-4 a.m. time period, while Windsor demonstrated significant decreases in impaired driving charges for 1-2 a.m. Sunday-Wednesday and Thursday-Saturday time periods and significant increases for Sunday-Wednesday 2-3 and 3-4 a.m. and for Thursday-Saturday 2-3 a.m. For assault charges, no overall pre-post differences were found for the aggregated 11 p.m.-4 a.m. time period for either city. When the data were disaggregated by hour, a significant decrease was found in London for Thursday-Saturday 1-2 a.m. and significant increases for Sunday-Wednesday 2-3 a.m. and Thursday-Saturday 3-4 a.m. time periods, while no significant decreases were found in Windsor during the 1-2 a.m. time periods and one significant increase occurred during the Thursday-Saturday 2-3 a.m. time period. These findings, based on police data, suggest no overall effect on charges aggregated over the 11 p.m. to 4 a.m. time window, although some differences were observed for the different hours after 2 a.m., with a possible effect of the one hour extension of drinking in licensed establishments.

Estimating aggregate regional user on-time reliability benefit from pre-trip ATIS : Seattle case study

DOT National Transportation Integrated Search

2003-12-01

This study explores the on-time reliability benefits to potential users of a personalized advanced traveler information system (ATIS) providing real-time pre-trip roadway information for the Seattle morning peak period through the application of Heur...

Impact of sleep duration on seizure frequency in adults with epilepsy: a sleep diary study.

PubMed

Cobabe, Maurine M; Sessler, Daniel I; Nowacki, Amy S; O'Rourke, Colin; Andrews, Noah; Foldvary-Schaefer, Nancy

2015-02-01

Prolonged sleep deprivation activates epileptiform EEG abnormalities and seizures in people with epilepsy. Few studies have addressed the effect of chronic partial sleep deprivation on seizure occurrence in populations with epilepsy. We tested the primary hypothesis that partial sleep deprivation over 24- and 72-hour periods increases seizure occurrence in adults with epilepsy. Forty-four subjects completed a series of self-reported instruments, as well as 1-month sleep and seizure diaries, to characterize their sleep and quality of life. Diaries were used to determine the relationship between seizure occurrence and total sleep time 24 and 72h before seizure occurrence using random effects models and a logistic regression model fit by generalized estimating equations. A total of 237 seizures were recorded during 1295 diary days, representing 5.5±7.0 (mean±SD) seizures per month. Random effects models for 24- and 72-hour total sleep times showed no clinically or statistically significant differences in the total sleep time between preseizure periods and seizure-free periods. The average 24-hour total sleep time during preseizure 24-hour periods was 8min shorter than that during seizure-free periods (p=0.51). The average 72-hour total sleep time during preseizure periods was 20min longer than that during seizure-free periods (p=0.86). The presence of triggers was a significant predictor of seizure occurrence, with stress/anxiety noted most often as a trigger. Mean total sleep time was 9h, and subjects took an average of 12±10 naps per month, having a mean duration of 1.9±1.2h. Daytime sleepiness, fatigue, and insomnia symptoms were commonly reported. Small degrees of sleep loss were not associated with seizure occurrence in our sample of adults with epilepsy. Our results also include valuable observations of the altered sleep times and frequent napping habits of adults with refractory epilepsy and the potential contribution of these habits to quality of life and seizure control. Copyright © 2014 Elsevier Inc. All rights reserved.

[Duration of the pre-nesting period and its relation with social organization in sandpipers (Charadrii, Aves) nesting in north-east Yakutia].

PubMed

Gavrilov, V V

2013-01-01

Investigations were carried out at two stations of Ornithological Unit, IBPN FEB RAS, located in Nizhnekolymsk District, Yakutia, starting from May 18-20 in 1984, 1985, 1987, 1988 and 1990. Duration of the pre-nesting period in 11 sandpiper species with different social organization was studied and compared with each other by allometric equations. As a characteristic of bird size the body mass was selected. Sandpipers come flying to the tundra at almost critical temperatures, to begin breeding as early as possible. Tining of breeding depends on birds feeding manner and the proximity to sites of overwintering. Duration of the pre-nesting period is invariable for every bird species and sex. There are sexual distinctions in time spent for the pre-nesting period in jointly-nesting sandpipers. The exponents in allometric equations that relate duration of the pre-nesting period with body mass are constant within a particular sex and differ between males and females. In different sexes, time spent for the pre-nesting period depends on mating, parental, and territorial systems. In sandpipers' males and females, this time is determined by the type of social organization. Relatively large sandpiper species seek to shortening of the pre-nesting period calendar time, which constrains their social organization. Monogamy and pair parental care lead to a necessity for spatial population structure to be controlled more strictly and maintained for a longer time. This, in turn, causes the increasing of males' time expenditures for such a behavior.

Effect of a Real-Time Pediatric ICU Safety Bundle Dashboard on Quality Improvement Measures.

PubMed

Shaw, Susanna J; Jacobs, Brian; Stockwell, David C; Futterman, Craig; Spaeder, Michael C

2015-09-01

Patient daily goal sheets have been shown to improve compliance with hospital policies but might not represent the dynamic nature of care delivery in the pediatric ICU (PICU) setting. A study was conducted at Children's National Health System (Washington, DC) to determine the effect of a visible, unitwide, real-time dashboard on timeliness of compliance with quality and safety measures. An automated electronic health record (EHR)- querying tool was created to assess compliance with a PICU Safety Bundle. Querying of the EHR for compliance and updating of the dashboard automatically occurred every five minutes. A real-time visual display showed data on presence of consent for treatment, restraint orders, presence of urinary catheters, deep venous thrombosis (DVT) prophylaxis, Braden Q score, and medication reconciliation. Baseline compliance and duration of noncompliance was established during three time periods: the first, before activation of the dashboard; the second, at one month following activation of the dashboard; and the third, at three months after activation. A total of 450 patients were included in the analysis. Between the first and third time periods, the median time from PICU admission to obtaining treatment consent decreased by 49%, from 393 to 202 minutes (p=.05). The number of patients with urinary catheters in place>96 hours decreased from 16 (32%) in Period 1 to 11 (19%) for Periods 2 and 3 combined (p=.01). Completion of medication reconciliation improved from 80% in the first time period to 93% and 92%, respectively, in the subsequent two periods (p=.002). There was no difference between the three periods in presence of restraint orders, DVT prophylaxis, or development or worsening of pressure ulcers. A unitwide dashboard can increase awareness for potential interventions, affecting patient safety in the PICU in a dynamic manner.

Time-Perception Network and Default Mode Network Are Associated with Temporal Prediction in a Periodic Motion Task

PubMed Central

Carvalho, Fabiana M.; Chaim, Khallil T.; Sanchez, Tiago A.; de Araujo, Draulio B.

2016-01-01

The updating of prospective internal models is necessary to accurately predict future observations. Uncertainty-driven internal model updating has been studied using a variety of perceptual paradigms, and have revealed engagement of frontal and parietal areas. In a distinct literature, studies on temporal expectations have also characterized a time-perception network, which relies on temporal orienting of attention. However, the updating of prospective internal models is highly dependent on temporal attention, since temporal attention must be reoriented according to the current environmental demands. In this study, we used functional magnetic resonance imaging (fMRI) to evaluate to what extend the continuous manipulation of temporal prediction would recruit update-related areas and the time-perception network areas. We developed an exogenous temporal task that combines rhythm cueing and time-to-contact principles to generate implicit temporal expectation. Two patterns of motion were created: periodic (simple harmonic oscillation) and non-periodic (harmonic oscillation with variable acceleration). We found that non-periodic motion engaged the exogenous temporal orienting network, which includes the ventral premotor and inferior parietal cortices, and the cerebellum, as well as the presupplementary motor area, which has previously been implicated in internal model updating, and the motion-sensitive area MT+. Interestingly, we found a right-hemisphere preponderance suggesting the engagement of explicit timing mechanisms. We also show that the periodic motion condition, when compared to the non-periodic motion, activated a particular subset of the default-mode network (DMN) midline areas, including the left dorsomedial prefrontal cortex (DMPFC), anterior cingulate cortex (ACC), and bilateral posterior cingulate cortex/precuneus (PCC/PC). It suggests that the DMN plays a role in processing contextually expected information and supports recent evidence that the DMN may reflect the validation of prospective internal models and predictive control. Taken together, our findings suggest that continuous manipulation of temporal predictions engages representations of temporal prediction as well as task-independent updating of internal models. PMID:27313526

Evolutionary orbital period change in BH Virginis

NASA Astrophysics Data System (ADS)

Gebrehiwot, Y. M.; Tessema, S. B.; Berdnikov, L. N.

2017-04-01

The study of orbital period change of close binaries, such as BH Virginis (BH Vir), using very long time baseline is vital to understand evolutionary processes of the system. In this paper, we use photometric data to analyze the evolutionary orbital period change of the short period RS CVn-type binary system, BH Vir, with a time baseline spanning 123 years. We used the software version of the Hertzsprung method to describe the O-C curve of the system, and we found that the orbital period secularly decreases at a rate of dp/dt=-(0.0013000 ± 0.0000863) s yr^{-1}. Because BH Vir is a typical detached binary system and both components are late type (G0 V + G2 V) stars, the evolutionary period change could be caused by the angular momentum loss due to tides coupled with magnetic breaking.

Time trend in the impact of heat waves on daily mortality in Spain for a period of over thirty years (1983-2013).

PubMed

Díaz, J; Carmona, R; Mirón, I J; Luna, M Y; Linares, C

2018-07-01

Many of the studies that analyze the future impact of climate change on mortality assume that the temperature that constitutes a heat wave will not change over time. This is unlikely, however, given the process of adapting to heat changes, prevention plans, and improvements in social and health infrastructure. The objective of this study is to analyze whether, during the 1983-2013 period, there has been a temporal change in the maximum daily temperatures that constitute a heat wave (T threshold ) in Spain, and to investigate whether there has been variation in the attributable risk (AR) associated with mortality due to high temperatures in this period. This study uses daily mortality data for natural causes except accidents CIEX: A00-R99 in municipalities of over 10,000 inhabitants in 10 Spanish provinces and maximum temperature data from observatories located in province capitals. The time series is divided into three periods: 1983-1992, 1993-2003 and 2004-2013. For each period and each province, the value of T threshold was calculated using scatter-plot diagram of the daily mortality pre-whitened series. For each period and each province capitals, it has been calculated the number of heat waves and quantifying the impact on mortality through generalized linear model (GLM) methodology with the Poisson regression link. These models permits obtained the relative risks (RR) and attributable risks (AR). Via a meta-analysis, using the Global RR and AR were calculated the heat impact for the total of the 10 provinces. The results show that in the first two periods RR remained constant RR: 1.14 (CI95%: 1.09 1.19) and RR: 1.14 (CI95%: 1.10 1.18), while the third period shows a sharp decrease with respect to the prior two periods RR: 1.01 (CI95%: 1.00 1.01); the difference is statistically significant. In Spain there has been a sharp decrease in mortality attributable to heat over the past 10 years. The observed variation in RR puts into question the results of numerous studies that analyze the future impact of heat on mortality in different temporal scenarios and show it to be constant over time. Copyright © 2018 Elsevier Ltd. All rights reserved.

Simulation-based power calculation for designing interrupted time series analyses of health policy interventions.

PubMed

Zhang, Fang; Wagner, Anita K; Ross-Degnan, Dennis

2011-11-01

Interrupted time series is a strong quasi-experimental research design to evaluate the impacts of health policy interventions. Using simulation methods, we estimated the power requirements for interrupted time series studies under various scenarios. Simulations were conducted to estimate the power of segmented autoregressive (AR) error models when autocorrelation ranged from -0.9 to 0.9 and effect size was 0.5, 1.0, and 2.0, investigating balanced and unbalanced numbers of time periods before and after an intervention. Simple scenarios of autoregressive conditional heteroskedasticity (ARCH) models were also explored. For AR models, power increased when sample size or effect size increased, and tended to decrease when autocorrelation increased. Compared with a balanced number of study periods before and after an intervention, designs with unbalanced numbers of periods had less power, although that was not the case for ARCH models. The power to detect effect size 1.0 appeared to be reasonable for many practical applications with a moderate or large number of time points in the study equally divided around the intervention. Investigators should be cautious when the expected effect size is small or the number of time points is small. We recommend conducting various simulations before investigation. Copyright © 2011 Elsevier Inc. All rights reserved.

The System of Secondary Periodicities and Resonances Based on β Lyrae Magnetic Field

NASA Astrophysics Data System (ADS)

Skulsky, M. Yu.

Original integral interconsistent and interconnected magnetohydrodynamical system of periodicities and resonances over their long-time variabilities is developed. The study is based upon three different observed secondary periods in β Lyrae system and taking into account geometrical features of the nonstandard magnetic field in a losing star, as well as due to the asynchronizm of the orbital and rotational periods.

Time allocated to mathematics in post-primary schools in Ireland: are we in double trouble?

NASA Astrophysics Data System (ADS)

O'Meara, Niamh; Prendergast, Mark

2018-05-01

Mathematics educators and legislators worldwide have begun placing a greater emphasis on teaching mathematics for understanding and through the use of real-life applications. Revised curricula have led to the time allocated to mathematics in effected countries being scrutinised. This has resulted in policy-makers and educationalists worldwide calling for the inclusion of double class periods on the mathematics timetable. Research from the United States suggests that the introduction of double or block periods allow for the objectives of revised curricula to be realized. The aim of this study, which is set in the school context, is first to ascertain if schools in Ireland are scheduling double periods for mathematics at both lower post-primary level (Junior Cycle) and upper post-primary level (Senior Cycle). It also seeks to determine if there is a link between teachers' levels of satisfaction with the time allocated to mathematics and the provision of double periods and to get insights from teachers in relation to their opinions on what can be achieved through the introduction of such classes. Questionnaires were sent to 400 post-primary schools (approximately 1600 teachers) which were selected using stratified sampling techniques. It was found that 8.7% of mathematics teachers reported the provision of double periods at Junior Cycle while 55% reported that double periods were included on their timetable at Senior Cycle. The study also identified a link between teachers' levels of satisfaction with the time allocated to mathematics and the provision of double periods. Finally, teachers felt that double periods allowed for new teaching methodologies, which were promoted by the revised curricula, to be implemented and teaching for understanding was also more feasible. In essence, it was found that double periods have an influence on the mathematical experience of post-primary students as well as the teaching approaches employed.

Drug exposure in register-based research—An expert-opinion based evaluation of methods

PubMed Central

Taipale, Heidi; Koponen, Marjaana; Tolppanen, Anna-Maija; Hartikainen, Sirpa; Ahonen, Riitta; Tiihonen, Jari

2017-01-01

Background In register-based pharmacoepidemiological studies, construction of drug exposure periods from drug purchases is a major methodological challenge. Various methods have been applied but their validity is rarely evaluated. Our objective was to conduct an expert-opinion based evaluation of the correctness of drug use periods produced by different methods. Methods Drug use periods were calculated with three fixed methods: time windows, assumption of one Defined Daily Dose (DDD) per day and one tablet per day, and with PRE2DUP that is based on modelling of individual drug purchasing behavior. Expert-opinion based evaluation was conducted with 200 randomly selected purchase histories of warfarin, bisoprolol, simvastatin, risperidone and mirtazapine in the MEDALZ-2005 cohort (28,093 persons with Alzheimer’s disease). Two experts reviewed purchase histories and judged which methods had joined correct purchases and gave correct duration for each of 1000 drug exposure periods. Results The evaluated correctness of drug use periods was 70–94% for PRE2DUP, and depending on grace periods and time window lengths 0–73% for tablet methods, 0–41% for DDD methods and 0–11% for time window methods. The highest rate of evaluated correct solutions for each method class were observed for 1 tablet per day with 180 days grace period (TAB_1_180, 43–73%), and 1 DDD per day with 180 days grace period (1–41%). Time window methods produced at maximum only 11% correct solutions. The best performing fixed method TAB_1_180 reached highest correctness for simvastatin 73% (95% CI 65–81%) whereas 89% (95% CI 84–94%) of PRE2DUP periods were judged as correct. Conclusions This study shows inaccuracy of fixed methods and the urgent need for new data-driven methods. In the expert-opinion based evaluation, the lowest error rates were observed with data-driven method PRE2DUP. PMID:28886089

French Medico-Administrative Data to Identify the Care Pathways of Women With Breast Cancer.

PubMed

Lefeuvre, Delphine; Le Bihan-Benjamin, Christine; Pauporté, Iris; Medioni, Jacques; Bousquet, Philippe-Jean

2017-07-01

Study of the care pathways is an important topic for care planning, as well as to observe guidelines application. This study aimed to describe care pathways and the period of time between treatments of women with breast cancer (BC), at a population level. Women with in situ, local and regional BC who were hospitalized and newly treated in 2012 were included and followed for 1 year. Care pathways were described, focusing on surgery (partial mastectomy [PM], total mastectomy [TM]), chemotherapy, and radiotherapy. The periods of time between treatments were measured and compared with the guidelines. The study involved 52,128 women. The most common care pathways among the 2845 women with in situ BC were PM-radiotherapy (46.7%) and TM (28.5%). Among the 41,470 women with local BC, they were: PM-radiotherapy (44.8%) or PM-chemotherapy-radiotherapy (16.0%). The 7813 women with regional BC had similar care pathways, although chemotherapy was given more frequently (73%). The periods of time between surgery and chemotherapy were in accordance with the guidelines for 98% of the women; those between surgery and radiotherapy were affected by adjuvant chemotherapy. Finally, the time between chemotherapy and radiotherapy was longer than recommended for 40% of the women. The French medicoadministrative databases allow the study, at a national population level, of the care pathways and periods of time between treatments of women with BC according to the stage of the disease. They were close to the guidelines, although an improvement is highly necessary. Copyright © 2017 Elsevier Inc. All rights reserved.

Variation of Time Domain Failure Probabilities of Jack-up with Wave Return Periods

NASA Astrophysics Data System (ADS)

Idris, Ahmad; Harahap, Indra S. H.; Ali, Montassir Osman Ahmed

2018-04-01

This study evaluated failure probabilities of jack up units on the framework of time dependent reliability analysis using uncertainty from different sea states representing different return period of the design wave. Surface elevation for each sea state was represented by Karhunen-Loeve expansion method using the eigenfunctions of prolate spheroidal wave functions in order to obtain the wave load. The stochastic wave load was propagated on a simplified jack up model developed in commercial software to obtain the structural response due to the wave loading. Analysis of the stochastic response to determine the failure probability in excessive deck displacement in the framework of time dependent reliability analysis was performed by developing Matlab codes in a personal computer. Results from the study indicated that the failure probability increases with increase in the severity of the sea state representing a longer return period. Although the results obtained are in agreement with the results of a study of similar jack up model using time independent method at higher values of maximum allowable deck displacement, it is in contrast at lower values of the criteria where the study reported that failure probability decreases with increase in the severity of the sea state.

Time Series Analysis of Sexual Assault Case Characteristics and the 2007–2008 Period of Post-Election Violence in Kenya

PubMed Central

Anastario, Michael P.; Adhiambo Onyango, Monica; Nyanyuki, Joan; Naimer, Karen; Muthoga, Rachel; Sirkin, Susannah; Barrick, Kelle; van Hasselt, Martijn; Aruasa, Wilson; Kibet, Cynthia; Omollo, Grace

2014-01-01

Background Following the declaration that President Mwai Kibaki was the winner of the Kenyan presidential election held on December 27, 2007, a period of post-election violence (PEV) took place. In this study, we aimed to identify whether the period of PEV in Kenya was associated with systematic changes in sexual assault case characteristics. Methods and Findings Medical records of 1,615 patients diagnosed with sexual assault between 2007 and 2011 at healthcare facilities in Eldoret (n = 569), Naivasha (n = 534), and Nakuru (n = 512) were retrospectively reviewed to examine characteristics of sexual assault cases over time. Time series and linear regression were used to examine temporal variation in case characteristics relative to the period of post-election violence in Kenya. Key informant interviews with healthcare workers at the sites were employed to triangulate findings. The time series of sexual assault case characteristics at these facilities were examined, with a specific focus on the December 2007–February 2008 period of post-election violence. Prais-Winsten estimates indicated that the three-month period of post-election violence was associated with a 22 percentage-point increase in cases where survivors did not know the perpetrator, a 20 percentage-point increase in cases with more than one perpetrator, and a 4 percentage-point increase in cases that had evidence of abdominal injury. The post-election violence period was also associated with an 18 percentage-point increase in survivors waiting >1 month to report to a healthcare facility. Sensitivity analyses confirmed that these characteristics were specific to the post-election violence time period. Conclusion These results demonstrate systematic patterns in sexual assault characteristics during the PEV period in Kenya. PMID:25170917

Longitudinal levels and bouts of sedentary time among adolescent girls.

PubMed

Carson, Valerie; Cliff, Dylan P; Janssen, Xanne; Okely, Anthony D

2013-10-21

Adolescent girls are one of the most sedentary demographic groups. A better understanding of their accumulation of sedentary time is needed to inform future interventions. The purpose of this study was to examine the longitudinal levels and bouts of objectively measured sedentary time accumulated during different days of the week and periods of the weekday among a large sample of adolescent girls. The results are based on 655 adolescent girls from the Girls in Sport Intervention and Research Project. Levels and bouts of sedentary time were derived from accelerometer data collected at baseline and 18-month follow-up. Total, weekday, weekend, school (i.e., morning bell to afternoon bell), after school (i.e., afternoon bell to 19:00), and evening (i.e. 19:01 to 23:59) sedentary time levels and bouts were calculated. Repeated-measures ANCOVAs were conducted to examine differences in sedentary time levels and bouts between days and time periods after adjusting for wear time, accelerometer model, and intervention group. Cross-sectional analyses revealed that levels and bouts of sedentary time were higher on weekdays compared to weekend days at baseline. Similar trends were observed at follow-up. In addition, percentage of wear time spent sedentary and bouts/hr of sedentary time were highest in the evening compared to the school and after school periods at both baseline and follow-up. Longitudinal analyses revealed that levels and bouts of sedentary time were higher at follow-up compared to baseline across the different days of the week and periods of the weekday examined, with the biggest increase (15%) occurring in the school period. Future interventions targeting sedentary time among adolescent girls should consider developing strategies to reduce and break up prolonged sedentary time during the school day and in the evening.

External foam and the post-mortem period in freshwater drowning; results from a retrospective study in Amsterdam, the Netherlands.

PubMed

Reijnen, G; Buster, M C; Vos, P J E; Reijnders, U J L

2017-11-01

Determining the time of death of bodies recovered from water can be difficult. A feature of drowning is the presence of external foam. This study describes the presence of external foam in relation to the post-mortem period. The study utilizes a database of death reports dated between January 2011 and July 2016. For bodies recovered from fresh water, the presence or absence of external foam was noted. In this study, 112 death reports are included. Of these reports, 18 mentioned external foam, which account for 16.1% of the entire study population. In the population with a post-mortem period of less than 24 h, external foam was detected in 27.7% of cases. All 18 incidents with external foam had an estimated post-mortem period of less than 24 h. In our study, external foam was only present in freshwater drowning cases with a post-mortem period of less than 24 h. Based on this finding, the presence of external foam may be useful as an additional indicator when estimating the time of death in freshwater drowning. Copyright © 2017 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

On the discretization and control of an SEIR epidemic model with a periodic impulsive vaccination

NASA Astrophysics Data System (ADS)

Alonso-Quesada, S.; De la Sen, M.; Ibeas, A.

2017-01-01

This paper deals with the discretization and control of an SEIR epidemic model. Such a model describes the transmission of an infectious disease among a time-varying host population. The model assumes mortality from causes related to the disease. Our study proposes a discretization method including a free-design parameter to be adjusted for guaranteeing the positivity of the resulting discrete-time model. Such a method provides a discrete-time model close to the continuous-time one without the need for the sampling period to be as small as other commonly used discretization methods require. This fact makes possible the design of impulsive vaccination control strategies with less burden of measurements and related computations if one uses the proposed instead of other discretization methods. The proposed discretization method and the impulsive vaccination strategy designed on the resulting discretized model are the main novelties of the paper. The paper includes (i) the analysis of the positivity of the obtained discrete-time SEIR model, (ii) the study of stability of the disease-free equilibrium point of a normalized version of such a discrete-time model and (iii) the existence and the attractivity of a globally asymptotically stable disease-free periodic solution under a periodic impulsive vaccination. Concretely, the exposed and infectious subpopulations asymptotically converge to zero as time tends to infinity while the normalized subpopulations of susceptible and recovered by immunization individuals oscillate in the context of such a solution. Finally, a numerical example illustrates the theoretic results.

Existence of time-periodic weak solutions to the stochastic Navier-Stokes equations around a moving body

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

Chen, Feng, E-mail: chenfengmath@163.com, E-mail: hanyc@jlu.edu.cn; Han, Yuecai, E-mail: chenfengmath@163.com, E-mail: hanyc@jlu.edu.cn

2013-12-15

The existence of time-periodic stochastic motions of an incompressible fluid is obtained. Here the fluid is subject to a time-periodic body force and an additional time-periodic stochastic force that is produced by a rigid body moves periodically stochastically with the same period in the fluid.

Statistical Analysis of Categorical Time Series of Atmospheric Elementary Circulation Mechanisms - Dzerdzeevski Classification for the Northern Hemisphere

PubMed Central

Brenčič, Mihael

2016-01-01

Northern hemisphere elementary circulation mechanisms, defined with the Dzerdzeevski classification and published on a daily basis from 1899–2012, are analysed with statistical methods as continuous categorical time series. Classification consists of 41 elementary circulation mechanisms (ECM), which are assigned to calendar days. Empirical marginal probabilities of each ECM were determined. Seasonality and the periodicity effect were investigated with moving dispersion filters and randomisation procedure on the ECM categories as well as with the time analyses of the ECM mode. The time series were determined as being non-stationary with strong time-dependent trends. During the investigated period, periodicity interchanges with periods when no seasonality is present. In the time series structure, the strongest division is visible at the milestone of 1986, showing that the atmospheric circulation pattern reflected in the ECM has significantly changed. This change is result of the change in the frequency of ECM categories; before 1986, the appearance of ECM was more diverse, and afterwards fewer ECMs appear. The statistical approach applied to the categorical climatic time series opens up new potential insight into climate variability and change studies that have to be performed in the future. PMID:27116375

Statistical Analysis of Categorical Time Series of Atmospheric Elementary Circulation Mechanisms - Dzerdzeevski Classification for the Northern Hemisphere.

PubMed

Brenčič, Mihael

2016-01-01

Northern hemisphere elementary circulation mechanisms, defined with the Dzerdzeevski classification and published on a daily basis from 1899-2012, are analysed with statistical methods as continuous categorical time series. Classification consists of 41 elementary circulation mechanisms (ECM), which are assigned to calendar days. Empirical marginal probabilities of each ECM were determined. Seasonality and the periodicity effect were investigated with moving dispersion filters and randomisation procedure on the ECM categories as well as with the time analyses of the ECM mode. The time series were determined as being non-stationary with strong time-dependent trends. During the investigated period, periodicity interchanges with periods when no seasonality is present. In the time series structure, the strongest division is visible at the milestone of 1986, showing that the atmospheric circulation pattern reflected in the ECM has significantly changed. This change is result of the change in the frequency of ECM categories; before 1986, the appearance of ECM was more diverse, and afterwards fewer ECMs appear. The statistical approach applied to the categorical climatic time series opens up new potential insight into climate variability and change studies that have to be performed in the future.

Detecting daily routines of older adults using sensor time series clustering.

PubMed

Hajihashemi, Zahra; Yefimova, Maria; Popescu, Mihail

2014-01-01

The aim of this paper is to develop an algorithm to identify deviations in patterns of day-to-day activities of older adults to generate alerts to the healthcare providers for timely interventions. Daily routines, such as bathroom visits, can be monitored by automated in-home sensor systems. We present a novel approach that finds periodicity in sensor time series data using clustering approach. For this study, we used data set from TigerPlace, a retirement community in Columbia, MO, where apartments are equipped with a network of motion, pressure and depth sensors. A retrospective multiple case study (N=3) design was used to quantify bathroom visits as parts of the older adult's daily routine, over a 10-day period. The distribution of duration, number, and average time between sensor hits was used to define the confidence level for routine visit extraction. Then, a hierarchical clustering was applied to extract periodic patterns. The performance of the proposed method was evaluated through experimental results.

[Risk factors for absenteeism due to sick leave in the petroleum industry].

PubMed

Oenning, Nágila Soares Xavier; Carvalho, Fernando Martins; Lima, Veronica Maria Cadena

2014-02-01

To identify risk factors for absenteeism among workers with sick leave in an oil company. A case-control study (120 cases and 656 controls) nested in a retrospective cohort study following up all employees of an oil company in the North-Northeast of Brazil from 2007 to 2009. The response variable used to represent absenteeism with sick leave was the average incidence of sick leave, defined as the ratio between total sick days and potential working days in the period. Logistic regression techniques were used to investigate the association between average incidence of sick leave > 5.0% over the period and the variables sex, position, age, time at work, shift work, smoking, arterial hypertension, body mass index, physical activity, coronary risk, sleep, glycemia, non-managed diabetes, cardiovascular, digestive, musculoskeletal, neurological and neoplastic diseases, straining body positioning during work, satisfaction at work, relationship with management, and concentrated attention at work. Average incidence of sick leave higher than 5.0% in the cohort period was 15.5%. The logistic model revealed that workers with average incidence of sick leave higher than 5.0% were 2.6 times more likely to be female; 2.0 time more likely to be smokers; 1.8 time more likely to be former smokers; 2.2 times more likely to report abnormal sleep and 10.5 times more likely to report dissatisfaction with their than workers with average incidence of sick leave ≤ 5.0% in the period. In this population, female gender, being a smoker or a former smoker, reporting dissatisfaction with the job and reporting abnormal sleep are good predictors of occupational absenteeism with sick leave. To identify risk factors for absenteeism among workers with sick leave in an oil company. A case-control study (120 cases and 656 controls) nested in a retrospective cohort study following up all employees of an oil company in the North-Northeast of Brazil from 2007 to 2009. The response variable used to represent absenteeism with sick leave was the average incidence of sick leave, defined as the ratio between total sick days and potential working days in the period. Logistic regression techniques were used to investigate the association between average incidence of sick leave > 5.0% over the period and the variables sex, position, age, time at work, shift work, smoking, arterial hypertension, body mass index, physical activity, coronary risk, sleep, glycemia, non-managed diabetes, cardiovascular, digestive, musculoskeletal, neurological and neoplastic diseases, straining body positioning during work, satisfaction at work, relationship with management, and concentrated attention at work. Average incidence of sick leave higher than 5.0% in the cohort period was 15.5%. The logistic model revealed that workers with average incidence of sick leave higher than 5.0% were 2.6 times more likely to be female; 2.0 time more likely to be smokers; 1.8 time more likely to be former smokers; 2.2 times more likely to report abnormal sleep and 10.5 times more likely to report dissatisfaction with their than workers with average incidence of sick leave ≤ 5.0% in the period. In this population, female gender, being a smoker or a former smoker, reporting dissatisfaction with the job and reporting abnormal sleep are good predictors of occupational absenteeism with sick leave.

PaleoClim: new datasets to quantify the impact of past climate changes on modern biodiversity

NASA Astrophysics Data System (ADS)

Hill, D. J.; Brown, J. T.; Carnaval, A. C.; Haywood, A. M.

2017-12-01

Palaeoclimate history is an important driver of modern patterns of biodiversity and many ecological modelling studies have shown the predictive power of palaeoclimate information. However, a major limiting factor to such studies is the availability of global palaeoclimate reconstructions in the relevant bioclim layers. The primary source of such fields is from climate model simulations, which are currently limited to the key PMIP (Paleoclimate Modelling Intercomparison Project) intervals of the mid-Holocene (6ka), the Last Glacial Maximum (21ka) and the Last Interglaciation (130ka). The PaleoClim project will significantly increase the availability of pre-processed palaeoclimate bioclim information and provide a new platform for accessing the information. The first new PaleoClim time period will be the mid-Pliocene Warm Period (3Ma). This is the last period of sustained globally warmer than modern climate in Earth history and represents the last global warmth before the cooling into the Pleistocene ice ages. Being 3 million years ago this represents a significant lengthening of the time range of available bioclim layers and the first time these have been available over evolutionary timescales. PaleoClim will also greatly expand the available Pleistocene time periods, looking to both quantify the differences between the late Pleistocene interglacial periods and understand the role of orbital changes in modulating tropical precipitation and driving modern biodiversity patterns.

Preoperative fasting times in elective surgical patients at a referral Hospital in Botswana

PubMed Central

Abebe, Worknehe Agegnehu; Rukewe, Ambrose; Bekele, Negussie Alula; Stoffel, Moeng; Dichabeng, Mompelegi Nicoh; Shifa, Jemal Zeberga

2016-01-01

Introduction Adults and children are required to fast before anaesthesia to reduce the risk of regurgitation and aspiration of gastric contents. However, prolonged periods of fasting are unnecessary and may cause complications. This study was conducted to evaluate preoperative fasting period in our centre and compare it with the ASA recommendations and factors that influence fasting periods. Methods This is a cross-sectional study of preoperative fasting times among elective surgical patients. A total numbers of 260 patients were interviewed as they arrived at the reception area of operating theatre using questionnaire. Results Majority of patients (98.1%) were instructed to fast from midnight. Fifteen patients (5.8%) reported that they were told the importance of preoperative fasting. The mean fasting period were 15.9±2.5 h (range 12.0-25.3 h) for solids and 15.3±2.3 h (range 12.0-22.0 h) for liquids. The mean duration of fasting was significantly longer for patients operated after midday compared to those operated before midday, p<0.001. Conclusion The mean fasting periods were 7.65 times longer for clear liquid and 2.5 times for solids than the ASA guidelines. It is imperative that the Hospital should establish Preoperative fasting policies and teach the staff who should ensure compliance with guidelines. PMID:27222691

21 CFR 99.303 - Extension of time for completing planned studies.

Code of Federal Regulations, 2010 CFR

2010-04-01

... DEVICES FDA Action on Submissions, Requests, and Applications § 99.303 Extension of time for completing... conducting studies needed for the submission of a supplemental application for a new use, FDA may, with or... writing that FDA extend the time period for conducting studies needed for the submission of a supplemental...

21 CFR 99.303 - Extension of time for completing planned studies.

Code of Federal Regulations, 2011 CFR

2011-04-01

... DEVICES FDA Action on Submissions, Requests, and Applications § 99.303 Extension of time for completing... conducting studies needed for the submission of a supplemental application for a new use, FDA may, with or... writing that FDA extend the time period for conducting studies needed for the submission of a supplemental...

21 CFR 99.303 - Extension of time for completing planned studies.

Code of Federal Regulations, 2012 CFR

2012-04-01

... DEVICES FDA Action on Submissions, Requests, and Applications § 99.303 Extension of time for completing... conducting studies needed for the submission of a supplemental application for a new use, FDA may, with or... writing that FDA extend the time period for conducting studies needed for the submission of a supplemental...

21 CFR 99.303 - Extension of time for completing planned studies.

Code of Federal Regulations, 2013 CFR

2013-04-01

... DEVICES FDA Action on Submissions, Requests, and Applications § 99.303 Extension of time for completing... conducting studies needed for the submission of a supplemental application for a new use, FDA may, with or... writing that FDA extend the time period for conducting studies needed for the submission of a supplemental...

In-Patient Code Stroke: A Quality Improvement Strategy to Overcome Knowledge-to-Action Gaps in Response Time.

PubMed

Kassardjian, Charles D; Willems, Jacqueline D; Skrabka, Krystyna; Nisenbaum, Rosane; Barnaby, Judith; Kostyrko, Pawel; Selchen, Daniel; Saposnik, Gustavo

2017-08-01

Stroke is a relatively common and challenging condition in hospitalized patients. Previous studies have shown delays in recognition and assessment of inpatient strokes leading to poor outcomes. The goal of this quality improvement initiative was to evaluate an in-hospital code stroke algorithm and educational program aimed at reducing the response times for inpatient stroke. An inpatient code stroke algorithm was developed, and an educational intervention was implemented over 5 months. Data were recorded and compared between the 36-month period before and the 15-month period after the intervention was implemented. Outcome measures included time from last seen normal to initial assessment and from last seen normal to brain imaging. During the study period, there were 218 inpatient strokes (131 before the intervention and 87 after the intervention). Inpatient strokes were more common on cardiovascular wards (45% of cases) and occurred mainly during the perioperative period (60% of cases). After implementation of an inpatient code stroke intervention and educational initiative, there were consistent reductions in all timed outcome measures (median time to initial assessment fell from 600 [109-1460] to 160 [35-630] minutes and time to computed tomographic scan fell from 925 [213-1965] to 348.5 [128-1587] minutes). Our study reveals the efficacy of an inpatient code stroke algorithm and educational intervention directed at nurses and allied health personnel to optimize the prompt management of inpatient strokes. Prompt assessment may lead to faster stroke interventions, which are associated with better outcomes. © 2017 American Heart Association, Inc.

Trends in socioeconomic inequalities in mortality in small areas of 33 Spanish cities.

PubMed

Marí-Dell'Olmo, Marc; Gotsens, Mercè; Palència, Laia; Rodríguez-Sanz, Maica; Martinez-Beneito, Miguel A; Ballesta, Mónica; Calvo, Montse; Cirera, Lluís; Daponte, Antonio; Domínguez-Berjón, Felicitas; Gandarillas, Ana; Goñi, Natividad Izco; Martos, Carmen; Moreno-Iribas, Conchi; Nolasco, Andreu; Salmerón, Diego; Taracido, Margarita; Borrell, Carme

2016-07-29

In Spain, several ecological studies have analyzed trends in socioeconomic inequalities in mortality from all causes in urban areas over time. However, the results of these studies are quite heterogeneous finding, in general, that inequalities decreased, or remained stable. Therefore, the objectives of this study are: (1) to identify trends in geographical inequalities in all-cause mortality in the census tracts of 33 Spanish cities between the two periods 1996-1998 and 2005-2007; (2) to analyse trends in the relationship between these geographical inequalities and socioeconomic deprivation; and (3) to obtain an overall measure which summarises the relationship found in each one of the cities and to analyse its variation over time. Ecological study of trends with 2 cross-sectional cuts, corresponding to two periods of analysis: 1996-1998 and 2005-2007. Units of analysis were census tracts of the 33 Spanish cities. A deprivation index calculated for each census tracts in all cities was included as a covariate. A Bayesian hierarchical model was used to estimate smoothed Standardized Mortality Ratios (sSMR) by each census tract and period. The geographical distribution of these sSMR was represented using maps of septiles. In addition, two different Bayesian hierarchical models were used to measure the association between all-cause mortality and the deprivation index in each city and period, and by sex: (1) including the association as a fixed effect for each city; (2) including the association as random effects. In both models the data spatial structure can be controlled within each city. The association in each city was measured using relative risks (RR) and their 95 % credible intervals (95 % CI). For most cities and in both sexes, mortality rates decline over time. For women, the mortality and deprivation patterns are similar in the first period, while in the second they are different for most cities. For men, RRs remain stable over time in 29 cities, in 3 diminish and in 1 increase. For women, in 30 cities, a non-significant change over time in RR is observed. However, in 4 cities RR diminishes. In overall terms, inequalities decrease (with a probability of 0.9) in both men (RR = 1.13, 95 % CI = 1.12-1.15 in the 1st period; RR = 1.11, 95 % CI = 1.09-1.13 in the 2nd period) and women (RR = 1.07, 95 % CI = 1.05-1.08 in the 1st period; RR = 1.04, 95 % CI = 1.02-1.06 in the 2nd period). In the future, it is important to conduct further trend studies, allowing to monitoring trends in socioeconomic inequalities in mortality and to identify (among other things) temporal factors that may influence these inequalities.

Correlates of children’s time-specific physical activity: A review of the literature

PubMed Central

2012-01-01

Assessment of correlates of physical activity occurring at different times of the day, locations and contexts, is imperative to understanding children’s physical activity behaviour. The purpose of this review was to identify the correlates of children’s physical activity (aged 8–14 years) occurring during the school break time and after-school periods. A review was conducted of the peer-reviewed literature, published between 1990 and January 2011. A total of 22 studies (12 school break time studies, 10 after-school studies) were included in the review. Across the 22 studies, 17 studies were cross-sectional and five studies were interventions. In the school break time studies, 39 potential correlates were identified, of which gender and age were consistently associated with school break time physical activity in two or more studies, and family affluence, access to a gym, access to four or more physical activity programs and the condition of a playing field were all associated with school break time physical activity in only one study. Access to loose and fixed equipment, playground markings, size of and access to play space and the length of school break time were all positively associated with changes in school break time physical activity in intervention studies. Thirty-six potential correlates of after-school physical activity were identified. Gender (with boys more active), younger age, lower body mass index (for females), lower TV viewing/playing video games, and greater access to facilities were associated with higher levels of after-school physical activity in two or more studies. Parent supervision was negatively associated with females’ after-school physical activity in one study. This review has revealed a relatively small number of studies investigating the school break time and after-school periods in the specified age range and only a few correlates have demonstrated a consistent association with physical activity. This highlights the infancy of this area and a need for further investigation into time-specific physical activity behaviour so that interventions designed for these specific periods can target the important correlates. PMID:22546218

Period doubling in period-one steady states

NASA Astrophysics Data System (ADS)

Wang, Reuben R. W.; Xing, Bo; Carlo, Gabriel G.; Poletti, Dario

2018-02-01

Nonlinear classical dissipative systems present a rich phenomenology in their "route to chaos," including period doubling, i.e., the system evolves with a period which is twice that of the driving. However, typically the attractor of a periodically driven quantum open system evolves with a period which exactly matches that of the driving. Here, we analyze a periodically driven many-body open quantum system whose classical correspondent presents period doubling. We show that by studying the dynamical correlations, it is possible to show the occurrence of period doubling in the quantum (period-one) steady state. We also discuss that such systems are natural candidates for clean and intrinsically robust Floquet time crystals.

Dynamic fMRI of a decision-making task

NASA Astrophysics Data System (ADS)

Singh, Manbir; Sungkarat, Witaya

2008-03-01

A novel fMRI technique has been developed to capture the dynamics of the evolution of brain activity during complex tasks such as those designed to evaluate the neural basis of decision-making under different situations. A task called the Iowa Gambling Task was used as an example. Six normal human volunteers were studied. The task was presented inside a 3T MRI and a dynamic fMRI study of the approximately 2s period between the beginning and end of the decision-making period was conducted by employing a series of reference functions, separated by 200 ms, designed to capture activation at different time-points within this period. As decision-making culminates with a button-press, the timing of the button press was chosen as the reference (t=0) and corresponding reference functions were shifted backward in steps of 200ms from this point up to the time when motor activity from the previous button press became predominant. SPM was used to realign, high-pass filter (cutoff 200s), normalize to the Montreal Neurological Institute (MNI) Template using a 12 parameter affine/non-linear transformation, 8mm Gaussian smoothing, and event-related General Linear Model analysis for each of the shifted reference functions. The t-score of each activated voxel was then examined to find its peaking time. A random effect analysis (p<0.05) showed prefrontal, parietal and bi-lateral hippocampal activation peaking at different times during the decision making period in the n=6 group study.

Reduction of post-surgical scarring with the use of ablative fractional CO2 lasers: A pilot study using a porcine model.

PubMed

Baca, Marissa E; Neaman, Keith C; Rapp, Derek A; Burton, Michael E; Mann, Robert J; Renucci, John D

2017-01-01

Wound healing inevitably leads to scarring, which leads to functional and cosmetic defects. It is the goal of this study to investigate the immediate use of ablative fractional CO 2 lasers to reduce post-operative scarring secondary to surgical wounds. In this prospective controlled study, 20 surgical incisions were created on each of three pigs. Fifteen of the incisions were treated with an ablative fractional CO 2 laser at one of three laser settings. The remaining five incisions served as a control. Punch biopsies were taken post-operatively over time. Digital photographs were taken of each incisional scar at each time period. Blinded evaluators used a previously verified scoring system to score photographs of the incisional scars taken at the 6 month time period. With regards to the comparison between the three individual laser treatment groups and the control, there were no statistically significant effects for treatment (P = 0.40), time (P = 0.48), or for the interaction of time and treatment (P = 0.57). With regards to the visual assessment tool, there were no statistically significant differences between treatments for Overall Appearance (P = 0.21) or for Total Score (P = 0.24). In the limited setting of this pilot study, treatment of surgical incisions with ablative fractional CO 2 lasers does not significantly lessen scar formation. In addition, photographic analysis was not able to demonstrate a significant difference. Future studies on this topic will need a larger sample size to better answer whether a statistically significant difference may exist. Lasers Surg. Med. 49:122-128, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Assessing Correlation of Residency Applicants' Interview Dates With Likelihood of Matching.

PubMed

Avasarala, Sameer; Thompson, Elizabeth; Whitehouse, Sarah; Drake, Sean

2018-02-01

This study aimed to determine whether the timing of an interview relative to the recruitment season was associated with being ranked or matched at an academic medical center. Eleven specialties (anesthesiology, diagnostic radiology, emergency medicine, family medicine, general surgery, internal medicine, neurology, neurosurgery, obstetrics-gynecology, orthopedic surgery, and psychiatry) that participated in the National Resident Matching Program were included in the study. Each program's total number of interview days during the October 2014-January 2015 interview season were divided equally into three interview time periods. The Cochran-Armitage trend test was used to evaluate associations among the three interview time periods (early, middle, and late) and interviewee outcomes (ranked or matched at our institution) for all subjects combined for each of the 11 programs and for specialty groups (medical, surgical, and hospital). Of 1034 applicants included in the analyses, 60% were men. Most were graduated from US medical schools (59.8%; a total of 103 applicants obtained first-year training positions through the Match [95.4% combined fill rate]). Twenty-nine interviewed early, 38 in the middle, and 36 in the late period ( P = 0.3877). A total of 864 applicants were ranked by 1 of the 11 residency programs at the study site: 267 in the early period, 319 in the middle, and 278 in the late period ( P = 0.4184). Being ranked in association with specialty classification also showed no significant differences. Interview timing had no relation to the likelihood of a match or being ranked by 1 of the 11 programs studied at our institution. These findings help dispel misconceptions about the importance of the interview date for a successful match.

Acclimatization in first-time hearing aid users using three different fitting protocols.

PubMed

Reber, Monika Bertges; Kompis, Martin

2005-12-01

To study auditory acclimatization and outcome in first time hearing aid users fitted with state of the art hearing aids as a function of different hearing aid fitting protocols. Twenty-eight adult subjects participated in the study. Each subject was assigned to one of three study groups (named audiologist driven, AD; patient driven, PD; set-to-target, STT according to the fitting protocol used) and fitted with digital hearing aids (Bernafon Symbio). Speech recognition scores were measured in aided and unaided conditions over a 6-month period. Five subjects (three from the PD-group, two from the STT group) decided to withdraw from the study during the 6-month-study period, leaving a total of 23 complete data sets for analysis. Aided speech understanding increased significantly over this time period in all three groups. However, average hearing aid insertion gain changes were small over the same period. There were no statistically significant differences in aided or unaided speech recognition scores between the three groups after 2 weeks or after 6 months. On average, twice as many fine tunings of the hearing aids were requested by the patients in the AD and the STT group than in the PD group and subjects in the AD and STT group used their hearing aids approximately twice as much as subjects in the PD group. The substantial increase in speech intelligibility without significant changes of the insertion gain of the hearing aids over a 6-month period in all three groups suggests a significant acclimatization effect. Although the speech recognition with hearing aids did not differ significantly among the three study groups after 6 months, the lower average wearing time and the higher number of withdrawals from the study in the PD group suggest that the patients' needs are not adequately met. In terms of aided speech recognition scores and hearing aid wearing time the STT group and the AD group were very similar. However, comments of the patients and the higher rate of withdrawals in the STT group suggest an over-all advantage for the AD fitting protocol.

Quasi-periodic pulsations in solar hard X-ray and microwave flares

NASA Technical Reports Server (NTRS)

Kosugi, Takeo; Kiplinger, Alan L.

1986-01-01

For more than a decade, various studies have pointed out that hard X-ray and microwave time profiles of some solar flares show quasi-periodic fluctuations or pulsations. Nevertheless, it was not until recently that a flare displaying large amplitude quasi-periodic pulsations in X-rays and microwaves was observed with good spectral coverage and with a sufficient time resolution. The event occurred on June 7, 1980, at approximately 0312 UT, and exhibits seven intense pulses with a quasi-periodicity of approximately 8 seconds in microwaves, hard X-rays, and gamma-ray lines. On May 12, 1983, at approximately 0253 UT, another good example of this type of flare was observed both in hard X-rays and in microwaves. Temporal and spectral characteristics of this flare are compared with the event of June 7, 1980. In order to further explore these observational results and theoretical scenarios, a study of nine additional quasi-periodic events were incorporated with the results from the two flares described. Analysis of these events are briefly summarized.

Foster home integration as a temporal indicator of relational well-being.

PubMed

Waid, Jeffrey; Kothari, Brianne H; McBeath, Bowen M; Bank, Lew

2017-12-01

This study sought to identify factors that contribute to the relational well-being of youth in substitute care. Using data from the [BLIND] study, youth responded to a 9-item measure of positive home integration, a scale designed to assess the relational experiences of youth to their caregivers and their integration into the foster home. Data were collected from youth in six month intervals, for an 18-month period of time. Latent growth curve modeling procedures were employed to determine if child, family, and case characteristics influenced youth's home integration trajectories. Results suggest stability in youth reports of home integration over time; however, children who were older at the time of study enrollment and youth who experienced placement changes during the period of observation experienced decreased home integration during the 18-month period. Results suggest youth's perspectives of home integration may in part be a function of the child's developmental stage and their experiences with foster care placement instability. Implications for practice and future research are discussed.

Orbital forced frequencies in the 975000 year pollen record from Tenagi Philippon (Greece)

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

Mommersteeg, H.J.P.M.; Young, R.; Wijmstra, T.A.

Frequency analysis was applied to different time series obtained from the 975 ka pollen record of Tenagi Philippon (Macedonia, Greece). These time series are characteristic of different vegetation types related to specific climatic conditions. Time control of the 196 m deep core was based on 11 finite {sup 14}C dates in the upper 17 m, magnetostratigraphy and correlation with the marine oxygen isotope stratigraphy. Maximum entropy spectrum analyses and thomson multi-taper spectrum analysis were applied using the complete time series. Periods of 95-99, 40-45. 24.0-25.5 and 19-21 ka which can be related to orbital forcing, as well as periods ofmore » about 68, 30 ka and of about 15.5, 13.5, 12 and 10.5 ka were detected. The detected periods of about 68, 30 ka and 16, 14, 12, 10.5 ka are likely to be harmonics and combination tones of the periods related to orbital forcing. The period of around 30 ka is possibly a secondary peak of obliquity. To study the stability of the detected periods through time, analysis with a moving window was employed. Signals in the eccentricity band were detected clearly during the last 650 ka. In the precession band, detected periods of about 24 ka show an increase in amplitude during the last 650 ka. The evolution of orbital frequencies during the last 1.0 Ma is in general agreement with the results of other marine and continental time series. Time series related to different climatic settings showed a different response to orbital forcing. Time series of vegetational elements sensitive to changes in net precipitation were forced in the precession and obliquity bands. Changes in precession caused changes in the monsoon system, which indirectly had a strong influence on the climatic history of Greece. Time series of vegetational elements which are more indicative of changes in annual temperature are forced in the eccentricity band. 54 refs., 12 figs., 3 tabs.« less

Oral Fluency, Accuracy, and Complexity in Formal Instruction and Study Abroad Learning Contexts

ERIC Educational Resources Information Center

Mora, Joan C.; Valls-Ferrer, Margalida

2012-01-01

This study investigates the differential effects of two learning contexts, formal instruction (FI) at home and a study abroad period (SA), on the oral production skills of advanced-level Catalan-Spanish undergraduate learners of English. Speech samples elicited through an interview at three data collection times over a 2-year period were…

Disruption of the circadian period of body temperature by the anesthetic propofol.

PubMed

Touitou, Yvan; Mauvieux, Benoit; Reinberg, Alain; Dispersyn, Garance

2016-01-01

The circadian time structure of an organism can be desynchronized in a large number of instances, including the intake of specific drugs. We have previously found that propofol, which is a general anesthetic, induces a desynchronization of the circadian time structure in rats, with a 60-80 min significant phase advance of body temperature circadian rhythm. We thus deemed it worthwhile to examine whether this phase shift of body temperature was related to a modification of the circadian period Tau. Propofol was administered at three different Zeitgeber Times (ZTs): ZT6 (middle of the rest period), ZT10 (2 h prior to the beginning of activity period), ZT16 (4 h after the beginning of the activity period), with ZT0 being the beginning of the rest period (light onset) and ZT12 being the beginning of the activity period (light offset). Control rats (n = 20) were injected at the same ZTs with 10% intralipid, which is a control lipidic solution. Whereas no modification of the circadian period of body temperature was observed in the control rats, propofol administration resulted in a significant shortening of the period by 96 and 180 min at ZT6 and ZT10, respectively. By contrast, the period was significantly lengthened by 90 min at ZT16. We also found differences in the time it took for the rats to readjust their body temperature to the original 24-h rhythm. At ZT16, the speed of readjustment was more rapid than at the two other ZTs that we investigated. This study hence shows (i) the disruptive effects of the anesthetic propofol on the body temperature circadian rhythm, and it points out that (ii) the period Tau for body temperature responds to this anesthetic drug according to a Tau-response curve. By sustaining postoperative sleep-wake disorders, the disruptive effects of propofol on circadian time structure might have important implications for the use of this drug in humans.

Bayesian dynamic modeling of time series of dengue disease case counts.

PubMed

Martínez-Bello, Daniel Adyro; López-Quílez, Antonio; Torres-Prieto, Alexander

2017-07-01

The aim of this study is to model the association between weekly time series of dengue case counts and meteorological variables, in a high-incidence city of Colombia, applying Bayesian hierarchical dynamic generalized linear models over the period January 2008 to August 2015. Additionally, we evaluate the model's short-term performance for predicting dengue cases. The methodology shows dynamic Poisson log link models including constant or time-varying coefficients for the meteorological variables. Calendar effects were modeled using constant or first- or second-order random walk time-varying coefficients. The meteorological variables were modeled using constant coefficients and first-order random walk time-varying coefficients. We applied Markov Chain Monte Carlo simulations for parameter estimation, and deviance information criterion statistic (DIC) for model selection. We assessed the short-term predictive performance of the selected final model, at several time points within the study period using the mean absolute percentage error. The results showed the best model including first-order random walk time-varying coefficients for calendar trend and first-order random walk time-varying coefficients for the meteorological variables. Besides the computational challenges, interpreting the results implies a complete analysis of the time series of dengue with respect to the parameter estimates of the meteorological effects. We found small values of the mean absolute percentage errors at one or two weeks out-of-sample predictions for most prediction points, associated with low volatility periods in the dengue counts. We discuss the advantages and limitations of the dynamic Poisson models for studying the association between time series of dengue disease and meteorological variables. The key conclusion of the study is that dynamic Poisson models account for the dynamic nature of the variables involved in the modeling of time series of dengue disease, producing useful models for decision-making in public health.

Studying the time trend of Methicillin-resistant Staphylococcus aureus (MRSA) in Norway by use of non-stationary γ-Poisson distributions.

PubMed

Moxnes, John F; Moen, Aina E Fossum; Leegaard, Truls Michael

2015-10-05

Study the time development of methicillin-resistant Staphylococcus aureus (MRSA) and forecast future behaviour. The major question: Is the number of MRSA isolates in Norway increasing and will it continue to increase? Time trend analysis using non-stationary γ-Poisson distributions. Two data sets were analysed. The first data set (data set I) consists of all MRSA isolates collected in Oslo County from 1997 to 2010; the study area includes the Norwegian capital of Oslo and nearby surrounding areas, covering approximately 11% of the Norwegian population. The second data set (data set II) consists of all MRSA isolates collected in Health Region East from 2002 to 2011. Health Region East consists of Oslo County and four neighbouring counties, and is the most populated area of Norway. Both data sets I and II consist of all persons in the area and time period described in the Settings, from whom MRSA have been isolated. MRSA infections have been mandatory notifiable in Norway since 1995, and MRSA colonisation since 2004. In the time period studied, all bacterial samples in Norway have been sent to a medical microbiological laboratory at the regional hospital for testing. In collaboration with the regional hospitals in five counties, we have collected all MRSA findings in the South-Eastern part of Norway over long time periods. On an average, a linear or exponential increase in MRSA numbers was observed in the data sets. A Poisson process with increasing intensity did not capture the dispersion of the time series, but a γ-Poisson process showed good agreement and captured the overdispersion. The numerical model showed numerical internal consistency. In the present study, we find that the number of MRSA isolates is increasing in the most populated area of Norway during the time period studied. We also forecast a continuous increase until the year 2017. 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.

Risk of Stroke after Herpes Zoster - Evidence from a German Self-Controlled Case-Series Study.

PubMed

Schink, Tania; Behr, Sigrid; Thöne, Kathrin; Bricout, Hélène; Garbe, Edeltraut

2016-01-01

Herpes zoster (HZ) is caused by reactivation of the latent varicella-zoster virus (VZV). A severe complication of HZ is VZV vasculopathy which can result in ischemic or hemorrhagic stroke. The aims of our study were to assess the risk of stroke after the onset of HZ and to investigate the roles of stroke subtype, HZ location and the time interval between HZ onset and stroke. A self-controlled case-series study was performed on a cohort of patients with incident stroke recorded in the German Pharmacoepidemiological Research Database (GePaRD), which covers about 20 million persons throughout Germany. We estimated adjusted incidence rate ratios (IRR) by comparing the rate of stroke in risk periods (i.e., periods following HZ) with the rate of stroke in control periods (i.e., periods without HZ) in the same individuals, controlling for both time-invariant and major potentially time-variant confounders. The cohort included 124,462 stroke patients, of whom 6,035 (5%) had at least one HZ diagnosis identified in GePaRD either as main hospital discharge diagnosis or as HZ treated with antivirals. The risk of stroke was about 1.3 times higher in the risk periods 3 months after HZ onset, than in the control periods (IRR: 1.29; 95% confidence interval: 1.16-1.44). An elevated risk of similar magnitude was observed for ischemic and unspecified stroke, but a 1.5-fold higher risk was observed for hemorrhagic stroke. A slightly stronger effect on the risk of stroke was also observed during the 3 months after HZ ophthalmicus (HZO) onset (1.59; 1.10-2.32). The risk was highest 3 and 4 weeks after HZ onset and decreased thereafter. Our study corroborates an increased risk of stroke after HZ, which is highest 3 to 4 weeks after HZ onset. The results suggest that the risk is more pronounced after HZO and is numerically higher for hemorrhagic than for ischemic stroke.

Evolution of orbits of the Apollo group asteroids over 11550 years.

NASA Astrophysics Data System (ADS)

Zausaev, A. F.; Pushkarev, A. N.

The Everhart method is used to study the evolution of the orbits of 20 asteroids of the Apollo group over the time period from 9300 B.C. to 2250 A.D. Minimum distances of the asteroids to the major planets over the evolution process are calculated. The stability of resonances with Venus and Earth over the 9300 B.C.to 2250 A.D. time period is shown. Theoretical coordinates of radiants for the initial and final integration times are presented.

Detecting critical periods in larval flatfish populations

NASA Astrophysics Data System (ADS)

Chambers, R. Christopher; Witting, David A.; Lewis, Stephen J.

2001-06-01

We evaluate the time-course of deaths and evidence of periods of increased mortality (i.e., critical periods) in laboratory populations of larval flatfish. First, we make the distinction between age-at-death and abundance-at-time data for fish larvae, the latter being typical in studies of natural populations. Next, we describe an experimental investigation of age- and temperature-dependent mortality in larval winter flounder, Pseudopleuronectes americanus. The survivorship curves of these populations differed significantly in both the magnitude and time-course of mortality among the four water temperatures evaluated (7, 10, 13, and 16°C). Mortality was highest in the cooler temperatures and concentrated in the third quarter of larval life, largely concurrent with settlement of surviving members of the cohort. Among the statistical methods for analysing survival data, the proportional-hazards model with time-varying covariates proved best at capturing the patterns of age-specific mortalities. We conclude that fair appraisals of recruitment hypotheses which are predicated on periods of high, age-specific mortality that vary with environmental conditions (e.g., Hjort's critical period hypothesis) will require: (1) data that are based on age, not time; (2) data that are of higher temporal resolution than commonly available at present and (3) analytical methods that are sensitive to irregularities in survivorship curves. We suggest four research approaches for evaluating critical periods in nature.

Changes in American children’s time – 1997 to 2003

PubMed Central

Hofferth, Sandra L.

2010-01-01

Over the six-year period between 1997 and 2003 broad social changes occurred in the United States: welfare rules changed, the nation’s school policies were overhauled, America was attacked by terrorists, and American values shifted in a conservative direction. Changes in children’s time were consistent with these trends. Discretionary time declined. Studying and reading increased over the period, whereas participation in sports declined, suggesting that the increased emphasis on academics at the school level has altered children’s behavior at home as well. Increased participation in religious and youth activities and declines in outdoor activities may reflect changes in parental values and security concerns. The results suggest continuation of the upward trend in reading and studying from the 1980s and early 1990s, but increased religious attendance and youth group participation rather than increased participation in sports characterized this recent period. PMID:20852679

Robust design of (s, S) inventory policy parameters in supply chains with demand and lead time uncertainties

NASA Astrophysics Data System (ADS)

Karimi Movahed, Kamran; Zhang, Zhi-Hai

2015-09-01

Demand and lead time uncertainties have significant effects on supply chain behaviour. In this paper, we present a single-product three-level multi-period supply chain with uncertain demands and lead times by using robust techniques to study the managerial insights of the supply chain inventory system under uncertainty. We formulate this problem as a robust mixed-integer linear program with minimised expected cost and total cost variation to determine the optimal (s, S) values of the inventory parameters. Several numerical studies are performed to investigate the supply chain behaviour. Useful guidelines for the design of a robust supply chain are also provided. Results show that the order variance and the expected cost in a supply chain significantly increase when the manufacturer's review period is an integer ratio of the distributor's and the retailer's review periods.

Patterns of Orofacial Clefting in New York City From 1983 to 2010: Trends by Racial Background, Birthplace, and Public Health Strategies.

PubMed

Butts, Sydney C; Reynolds, Simone; Gitman, Lyuba; Patel, Prayag; Joseph, Michael

2018-01-01

To determine the role of racial background, public health initiatives, and residence on the prevalence of orofacial clefts (OFCs) in New York City (NYC). Retrospective review of OFC cases from the New York State Congenital Malformations Registry. Patients born with an OFC and all live births to mothers residing in NYC between 1983 and 2010. Orofacial cleft birth prevalence by cleft type, race, and borough of maternal residence for each year and by time period around the implementation of public health interventions including folate supplementation. A total of 3557 cases were reviewed. The prevalence remained stable for cleft palate and cleft lip with or without cleft palate (CL ± P) in sequential time periods of the study. Among CL ± P cases, cleft lip prevalence decreased early in the study compared to increases in cleft lip and palate prevalence. For most years, the prevalence of OFCs was lower among African Americans than whites. A total of 12% to 26% of mothers in 4 of the NYC boroughs deliver outside of their borough of residence, choosing to give birth in Manhattan most often. No difference in OFC prevalence was shown in any of the 5 NYC boroughs. The period prevalence remained relatively stable during the time periods before and after the implementation of folate supplementation for OFCs in NYC. Prevalence of OFC subtypes was lower for most time periods during this study among African Americans compared to whites. Several factors may explain the choice of birthplace outside of the mother's borough of residence.

Self-synchronizing Schlieren photography and interferometry for the visualization of unsteady transonic flows

NASA Technical Reports Server (NTRS)

Kadlec, R.

1979-01-01

The use of self synchronizing stroboscopic Schlieren and laser interferometer systems to obtain quantitative space time measurements of distinguished flow surfaces, steakline patterns, and the density field of two dimensional flows that exhibit a periodic content was investigated. A large field single path stroboscopic Schlieren system was designed, constructed and successfully applied to visualize four periodic flows: near wake behind an oscillating airfoil; edge tone sound generation; 2-D planar wall jet; and axisymmetric pulsed sonic jet. This visualization technique provides an effective means of studying quasi-periodic flows in real time. The image on the viewing screen is a spatial signal average of the coherent periodic motion rather than a single realization, the high speed motion of a quasi-periodic flow can be reconstructed by recording photographs of the flow at different fixed time delays in one cycle. The preliminary design and construction of a self synchronizing stroboscopic laser interferometer with a modified Mach-Zehnder optical system is also reported.

Quantification of differences between occupancy and total monitoring periods for better assessment of exposure to particles in indoor environments

NASA Astrophysics Data System (ADS)

Wierzbicka, A.; Bohgard, M.; Pagels, J. H.; Dahl, A.; Löndahl, J.; Hussein, T.; Swietlicki, E.; Gudmundsson, A.

2015-04-01

For the assessment of personal exposure, information about the concentration of pollutants when people are in given indoor environments (occupancy time) are of prime importance. However this kind of data frequently is not reported. The aim of this study was to assess differences in particle characteristics between occupancy time and the total monitoring period, with the latter being the most frequently used averaging time in the published data. Seven indoor environments were selected in Sweden and Finland: an apartment, two houses, two schools, a supermarket, and a restaurant. They were assessed for particle number and mass concentrations and number size distributions. The measurements using a Scanning Mobility Particle Sizer and two photometers were conducted for seven consecutive days during winter in each location. Particle concentrations in residences and schools were, as expected, the highest during occupancy time. In the apartment average and median PM2.5 mass concentrations during the occupancy time were 29% and 17% higher, respectively compared to total monitoring period. In both schools, the average and medium values of the PM2.5 mass concentrations were on average higher during teaching hours compared to the total monitoring period by 16% and 32%, respectively. When it comes to particle number concentrations (PNC), in the apartment during occupancy, the average and median values were 33% and 58% higher, respectively than during the total monitoring period. In both houses and schools the average and median PNC were similar for the occupancy and total monitoring periods. General conclusions on the basis of measurements in the limited number of indoor environments cannot be drawn. However the results confirm a strong dependence on type and frequency of indoor activities that generate particles and site specificity. The results also indicate that the exclusion of data series during non-occupancy periods can improve the estimates of particle concentrations and characteristics suitable for exposure assessment, which is crucial for estimating health effects in epidemiological and toxicological studies.

Modeling laser-induced periodic surface structures: Finite-difference time-domain feedback simulations

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

Skolski, J. Z. P., E-mail: j.z.p.skolski@utwente.nl; Vincenc Obona, J.; Römer, G. R. B. E.

2014-03-14

A model predicting the formation of laser-induced periodic surface structures (LIPSSs) is presented. That is, the finite-difference time domain method is used to study the interaction of electromagnetic fields with rough surfaces. In this approach, the rough surface is modified by “ablation after each laser pulse,” according to the absorbed energy profile, in order to account for inter-pulse feedback mechanisms. LIPSSs with a periodicity significantly smaller than the laser wavelength are found to “grow” either parallel or orthogonal to the laser polarization. The change in orientation and periodicity follow from the model. LIPSSs with a periodicity larger than the wavelengthmore » of the laser radiation and complex superimposed LIPSS patterns are also predicted by the model.« less

Time trends in the etiology of chronic pancreatitis in South India.

PubMed

Rajesh, Gopalakrishna; Girish, Banavara Narasimhamurthy; Panicker, Suprabha; Balakrishnan, Vallath

2014-01-01

Recent reports indicate a decline in prevalence of classical tropical chronic pancreatitis (TCP). We studied the etiologies and risk factors over a 14-year period at a tertiary care university hospital. We compared the etiology in chronic pancreatitis (CP) patients presenting and followed-up in our Pancreas Clinic over two time periods (2000-06 and 2007-13). Idiopathic chronic pancreatitis (ICP) was the predominant etiology seen over the two time periods. However an increase in prevalence of alcoholic chronic pancreatitis (ACP) during the latter time period suggests that it may be emerging as a dominant etiology over recent years. Hypertriglyceridemia and hyperparathyroidism were uncommon causes of non-alcoholic CP. Autoimmune pancreatitis was noted only during 2007-13, but remains a rare cause of CP. There are multiple risk factors for CP in our population. The high prevalence of ICP indicates need closer examination of risk factors and ICP pathogenesis. ACP appears to be emerging as a dominant cause of CP which suggests a need to reorient preventive strategies.

Characterizing Periodic Messaging Interventions Across Health Behaviors and Media: Systematic Review

PubMed Central

Fuentes, Laura W; Cohen, Joanna E

2014-01-01

Background Periodic prompts serve as tools for health behavior interventions to encourage and maintain behavior changes. Past literature reviews have examined periodic messages targeting specific behaviors (smoking, physical activity, diet, etc) or media (telephone, email, face-to-face, newsletter, etc) and have found them to be effective in impacting health behavior in the short term. Objective Our goal was to review the literature related to periodic messaging and prompts in order to explore typical characteristics, assess the role of prompt timing, identify common theoretical models used, and identify characteristics associated with the effectiveness of periodic prompts. Methods Electronic searches of PubMed, PsycINFO, CINAHL, and Web of Science were conducted in October 2012 and May 2013. Database search terms included variant terms for periods, prompts, interventions, media, and health behaviors. Results Forty-two of the 55 included research articles found that prompts resulted in significant positive behavioral outcomes for participants. Prompts were delivered via text messages, email, mailed communications, and in a few instances via phone. Generally, the provision of feedback and specific strategies to accomplish behavior change appears to be important for the success of periodic prompts. Rationale for prompt timing was rarely provided, although some studies did organize message content around days of the week or times perceived to be high risk for particular behaviors. Smoking cessation interventions tended to be organized around quit date. Among studies using theoretical models to inform their interventions, the transtheoretical model was most common. Conclusions Periodic messaging interventions yield positive results for short-term health behavior changes. Interventions including feedback and prompts that included strategies were more likely to report significantly positive outcomes. Work remains to better understand elements that make periodic prompts successful and whether they are effective in producing long-term outcomes. PMID:24667840

Factors Associated with the Time of Admission among Notified Dengue Fever Cases in Region VIII Philippines from 2008 to 2014

PubMed Central

Gil Cuesta, Julita; Cerro, Boyd Roderick; Guha-Sapir, Debarati

2016-01-01

In cases of Dengue fever, late hospital admission can lead to treatment delay and even death. In order to improve early disease notification and management, it is essential to investigate the factors affecting the time of admission of Dengue cases. This study determined the factors associated with the time of admission among notified Dengue cases. The study covered the period between 2008 and 2014 in Region VIII, Philippines. The factors assessed were age, sex, hospital sector, hospital level, disease severity based on the 1997 WHO Dengue classification, and period of admission (distinguishing between the 2010 Dengue epidemic and non-epidemic time). We analysed secondary data from the surveillance of notified Dengue cases. We calculated the association through chi-square test, ordinal logistic regression and linear regression at p value < 0.05. The study included 16,357 admitted Dengue cases. The reported cases included a majority of children (70.09%), mild cases of the disease (64.00%), patients from the public sector (69.82%), and non-tertiary hospitals (62.76%). Only 1.40% of cases had a laboratory confirmation. The epidemic period in 2010 comprised 48.68% of all the admitted cases during this period. Late admission was more likely among adults than children (p<0.05). The severe type of the disease was more likely to be admitted late than the mild type (p<0.05). Late admission was also more likely in public hospitals than in private hospitals (p<0.05); and within tertiary level hospitals than non-tertiary hospitals (p<0.05). Late admission was more likely during the non-epidemic period than the 2010 epidemic period (p<0.05). A case fatality rate of 1 or greater was significantly associated with children, severe diseases, tertiary hospitals and public hospitals when admitted late (p<0.05). Data suggests that early admission among child cases was common in Region VIII. This behavior is encouraging, and should be continued. However, further study is needed on the late admission among tertiary, public hospitals and non-epidemic period with reference to the quality of care, patient volume, out of pocket expense, and accessibility We recommend the consistent use of the 2009 WHO Dengue guidelines in order to standardize the admission criteria and time across hospitals. PMID:27780199

Impact of Robotic Antineoplastic Preparation on Safety, Workflow, and Costs

PubMed Central

Seger, Andrew C.; Churchill, William W.; Keohane, Carol A.; Belisle, Caryn D.; Wong, Stephanie T.; Sylvester, Katelyn W.; Chesnick, Megan A.; Burdick, Elisabeth; Wien, Matt F.; Cotugno, Michael C.; Bates, David W.; Rothschild, Jeffrey M.

2012-01-01

Purpose: Antineoplastic preparation presents unique safety concerns and consumes significant pharmacy staff time and costs. Robotic antineoplastic and adjuvant medication compounding may provide incremental safety and efficiency advantages compared with standard pharmacy practices. Methods: We conducted a direct observation trial in an academic medical center pharmacy to compare the effects of usual/manual antineoplastic and adjuvant drug preparation (baseline period) with robotic preparation (intervention period). The primary outcomes were serious medication errors and staff safety events with the potential for harm of patients and staff, respectively. Secondary outcomes included medication accuracy determined by gravimetric techniques, medication preparation time, and the costs of both ancillary materials used during drug preparation and personnel time. Results: Among 1,421 and 972 observed medication preparations, we found nine (0.7%) and seven (0.7%) serious medication errors (P = .8) and 73 (5.1%) and 28 (2.9%) staff safety events (P = .007) in the baseline and intervention periods, respectively. Drugs failed accuracy measurements in 12.5% (23 of 184) and 0.9% (one of 110) of preparations in the baseline and intervention periods, respectively (P < .001). Mean drug preparation time increased by 47% when using the robot (P = .009). Labor costs were similar in both study periods, although the ancillary material costs decreased by 56% in the intervention period (P < .001). Conclusion: Although robotically prepared antineoplastic and adjuvant medications did not reduce serious medication errors, both staff safety and accuracy of medication preparation were improved significantly. Future studies are necessary to address the overall cost effectiveness of these robotic implementations. PMID:23598843

Periodicity and time trends in the prevalence of total births and conceptions with congenital malformations among Jews and Muslims in Israel, 1999-2006: a time series study of 823,966 births.

PubMed

Agay-Shay, Keren; Friger, Michael; Linn, Shai; Peled, Ammatzia; Amitai, Yona; Peretz, Chava

2012-06-01

BACKGROUND Congenital malformations (CMs) are a leading cause of infant disability. Geophysical patterns such as 2-year, yearly, half-year, 3-month, and lunar cycles regulate much of the temporal biology of all life on Earth and may affect birth and birth outcomes in humans. Therefore, the aim of this study was to evaluate and compare trends and periodicity in total births and CM conceptions in two Israeli populations. METHODS Poisson nonlinear models (polynomial) were applied to study and compare trends and geophysical periodicity cycles of weekly births and weekly prevalence rate of CM (CMPR), in a time-series design of conception date within and between Jews and Muslims. The population included all live births and stillbirths (n = 823,966) and CM (three anatomic systems, eight CM groups [n = 2193]) in Israel during 2000 to 2006. Data were obtained from the Ministry of Health. RESULTS We describe the trend and periodicity cycles for total birth conceptions. Of eight groups of CM, periodicity cycles were statistically significant in four CM groups for either Jews or Muslims. Lunar month and biennial periodicity cycles not previously investigated in the literature were found to be statistically significant. Biennial cycle was significant in total births (Jews and Muslims) and syndactyly (Muslims), whereas lunar month cycle was significant in total births (Muslims) and atresia of small intestine (Jews). CONCLUSION We encourage others to use the method we describe as an important tool to investigate the effects of different geophysical cycles on human health and pregnancy outcomes, especially CM, and to compare between populations. Copyright © 2012 Wiley Periodicals, Inc.

Periodic-Zone Model Predictive Control for Diurnal Closed-Loop Operation of an Artificial Pancreas

PubMed Central

Gondhalekar, Ravi; Dassau, Eyal; Zisser, Howard C.; Doyle, Francis J.

2013-01-01

Background The objective of this research is an artificial pancreas (AP) that performs automatic regulation of blood glucose levels in people with type 1 diabetes mellitus. This article describes a control strategy that performs algorithmic insulin dosing for maintaining safe blood glucose levels over prolonged, overnight periods of time and furthermore was designed with outpatient, multiday deployment in mind. Of particular concern is the prevention of nocturnal hypoglycemia, because during sleep, subjects cannot monitor themselves and may not respond to alarms. An AP intended for prolonged and unsupervised outpatient deployment must strategically reduce the risk of hypoglycemia during times of sleep, without requiring user interaction. Methods A diurnal insulin delivery strategy based on predictive control methods is proposed. The so-called “periodic-zone model predictive control” (PZMPC) strategy employs periodically time-dependent blood glucose output target zones and furthermore enforces periodically time-dependent insulin input constraints to modulate its behavior based on the time of day. Results The proposed strategy was evaluated through an extensive simulation-based study and a preliminary clinical trial. Results indicate that the proposed method delivers insulin more conservatively during nighttime than during daytime while maintaining safe blood glucose levels at all times. In clinical trials, the proposed strategy delivered 77% of the amount of insulin delivered by a time-invariant control strategy; specifically, it delivered on average 1.23 U below, compared with 0.31 U above, the nominal basal rate overnight while maintaining comparable, and safe, blood glucose values. Conclusions The proposed PZMPC algorithm strategically prevents nocturnal hypoglycemia and is considered a significant step toward deploying APs into outpatient environments for extended periods of time in full closed-loop operation. PMID:24351171

On a possible additional component in an eclipsing binary system HS 2231 + 2441

NASA Astrophysics Data System (ADS)

Vidmachenko, A. P.; Romanyuk, Ya. O.; Shliahetskaya, Ya. O.

2016-05-01

Timing method based on the registration period of variations of a periodic process, associated with the star. The study of stellar eclipsing binary system for a long time allows a series of several transits, depending on the orbital period of the satellite smaller. We present a photometric study of system of the type HW Vir HS 2231 + 2441. Photometric data processing was performed using C-MuniWin Version 1.2.30 program. The accuracy of values for each observation point is in the range 0,003...0,009m for different nights. The calculated ephemeris determined from the light curve by fitting of arc of minimums to the nuclei of primary and secondary eclipses. The amplitude of the periodic changes of minimums moments that arise from the orbital motion of a close pair of stars around the barycenter of the triple system, is less than 0.0008 days (1.15 minutes). It was found that the periodic variation of the orbital period can be explained by the gravitational influence of a third companion on the central binary system with an orbital period of about 97±10d. Periodogram analysis of the observational data series indicate also on the periodicity with values of 48±5d and 195±15d, but with substantially less reliably

Radial variations of large-scale magnetohydrodynamic fluctuations in the solar wind

NASA Technical Reports Server (NTRS)

Burlaga, L. F.; Goldstein, M. L.

1983-01-01

Two time periods are studied for which comprehensive data coverage is available at both 1 AU using IMP-8 and ISEE-3 and beyond using Voyager 1. One of these periods is characterized by the predominance of corotating stream interactions. Relatively small scale transient flows characterize the second period. The evolution of these flows with heliocentric distance is studied using power spectral techniques. The evolution of the transient dominated period is consistent with the hypothesis of turbulent evolution including an inverse cascade of large scales. The evolution of the corotating period is consistent with the entrainment of slow streams by faster streams in a deterministic model.

Impact of thermal time shift on wheat phenology and yield under warming climate in the Huang-Huai-Hai Plain, China

NASA Astrophysics Data System (ADS)

Xiao, Dengpan; Qi, Yongqing; Li, Zhiqiang; Wang, Rende; Moiwo, Juana P.; Liu, Fengshan

2017-03-01

Given climate change can potentially influence crop phenology and subsequent yield, an investigation of relevant adaptation measures could increase the understanding and mitigation of these responses in the future. In this study, field observations at 10 stations in the Huang-Huai-Hai Plain of China (HHHP) are used in combination with the Agricultural Production Systems Simulator (APSIM)-Wheat model to determine the effect of thermal time shift on the phenology and potential yield of wheat from 1981-2009. Warming climate speeds up winter wheat development and thereby decreases the duration of the wheat growth period. However, APSIM-Wheat model simulation suggests prolongation of the period from flowering to maturity (Gr) of winter wheat by 0.2-0.8 d•10yr-1 as the number of days by which maturity advances, which is less than that by which flowering advances. Based on computed thermal time of the two critical growth phases of wheat, total thermal time from floral initiation to flowering (TT_floral_initiation) increasesd in seven out of the 10 investigated stations. Alternatively, total thermal time from the start of grainfilling to maturity (TT_start_ grain_fill) increased in all investigated stations, except Laiyang. It is thus concluded that thermal time shift during the past three decades (1981-2009) prolongs Gr by 0.2-3.0 d•10yr-1 in the study area. This suggests that an increase in thermal time (TT) of the wheat growth period is critical for mitigating the effect of growth period reduction due to warming climatic condition. Furthermore, climate change reduces potential yield of winter wheat in 80% of the stations by 2.3-58.8 kg•yr-1. However, thermal time shift (TTS) increases potential yield of winter wheat in most of the stations by 3.0-51.0 kg•yr-1. It is concluded that wheat cultivars with longer growth periods and higher thermal requirements could mitigate the negative effects of warming climate on crop production in the study area.

Integrating data from multiple time-location measurement methods for use in exposure assessment: the Multi-Ethnic Study of Atherosclerosis and Air Pollution (MESA Air).

PubMed

Hazlehurst, Marnie F; Spalt, Elizabeth W; Curl, Cynthia L; Davey, Mark E; Vedal, Sverre; Burke, Gregory L; Kaufman, Joel D

2017-11-01

Tools to assess time-location patterns related to environmental exposures have expanded from reliance on time-location diaries (TLDs) and questionnaires to use of geospatial location devices such as data-logging Global Positioning System (GPS) equipment. The Multi-Ethnic Study of Atherosclerosis and Air Pollution obtained typical time-location patterns via questionnaire for 6424 adults in six US cities. At a later time (mean 4.6 years after questionnaire), a subset (n=128) participated in high-resolution data collection for specific 2-week periods resulting in concurrent GPS and detailed TLD data, which were aggregated to estimate time spent in various microenvironments. During these 2-week periods, participants were observed to spend the most time at home indoors (mean of 78%) and a small proportion of time in-vehicle (mean of 4%). Similar overall patterns were reported by these participants on the prior questionnaire (mean home indoors: 75%; mean in-vehicle: 4%). However, individual micro-environmental time estimates measured over specific 2-week periods were not highly correlated with an individual's questionnaire report of typical behavior (Spearman's ρ of 0.43 for home indoors and 0.39 for in-vehicle). Although questionnaire data about typical time-location patterns can inform interpretation of long-term epidemiological analyses and risk assessment, they may not reliably represent an individual's short-term experience.

Evidence of solar activity and El Niño signals in tree rings of Araucaria araucana and A. angustifolia in South America

NASA Astrophysics Data System (ADS)

Perone, A.; Lombardi, F.; Marchetti, M.; Tognetti, R.; Lasserre, B.

2016-10-01

Tree rings reveal climatic variations through years, but also the effect of solar activity in influencing the climate on a large scale. In order to investigate the role of solar cycles on climatic variability and to analyse their influences on tree growth, we focused on tree-ring chronologies of Araucaria angustifolia and Araucaria araucana in four study areas: Irati and Curitiba in Brazil, Caviahue in Chile, and Tolhuaca in Argentina. We obtained an average tree-ring chronology of 218, 117, 439, and 849 years for these areas, respectively. Particularly, the older chronologies also included the period of the Maunder and Dalton minima. To identify periodicities and trends observable in tree growth, the time series were analysed using spectral, wavelet and cross-wavelet techniques. Analysis based on the Multitaper method of annual growth rates identified 2 cycles with periodicities of 11 (Schwebe cycle) and 5.5 years (second harmonic of Schwebe cycle). In the Chilean and Argentinian sites, significant agreement between the time series of tree rings and the 11-year solar cycle was found during the periods of maximum solar activity. Results also showed oscillation with periods of 2-7 years, probably induced by local environmental variations, and possibly also related to the El-Niño events. Moreover, the Morlet complex wavelet analysis was applied to study the most relevant variability factors affecting tree-ring time series. Finally, we applied the cross-wavelet spectral analysis to evaluate the time lags between tree-ring and sunspot-number time series, as well as for the interaction between tree rings, the Southern Oscillation Index (SOI) and temperature and precipitation. Trees sampled in Chile and Argentina showed more evident responses of fluctuations in tree-ring time series to the variations of short and long periodicities in comparison with the Brazilian ones. These results provided new evidence on the solar activity-climate pattern-tree ring connections over centuries.

The frequency of hippocampal theta rhythm is modulated on a circadian period and is entrained by food availability.

PubMed

Munn, Robert G K; Tyree, Susan M; McNaughton, Neil; Bilkey, David K

2015-01-01

The hippocampal formation plays a critical role in the generation of episodic memory. While the encoding of the spatial and contextual components of memory have been extensively studied, how the hippocampus encodes temporal information, especially at long time intervals, is less well understood. The activity of place cells in hippocampus has previously been shown to be modulated at a circadian time-scale, entrained by a behavioral stimulus, but not entrained by light. The experimental procedures used in the previous study of this phenomenon, however, necessarily conflated two alternative entraining stimuli, the exposure to the recording environment and the availability of food, making it impossible to distinguish between these possibilities. Here we demonstrate that the frequency of theta-band hippocampal EEG varies with a circadian period in freely moving animals and that this periodicity mirrors changes in the firing rate of hippocampal neurons. Theta activity serves, therefore, as a proxy of circadian-modulated hippocampal neuronal activity. We then demonstrate that the frequency of hippocampal theta driven by stimulation of the reticular formation also varies with a circadian period. Because this effect can be observed without having to feed the animal to encourage movement we were able to identify what stimulus entrains the circadian oscillation. We show that with reticular-activated recordings started at various times of the day the frequency of theta varies quasi-sinusoidally with a 25 h period and phase-aligned when referenced to the animal's regular feeding time, but not the recording start time. Furthermore, we show that theta frequency consistently varied with a circadian period when the data obtained from repeated recordings started at various times of the day were referenced to the start of food availability in the recording chamber. This pattern did not occur when data were referenced to the start of the recording session or to the actual time of day when this was not also related to feeding time. This double dissociation demonstrates that hippocampal theta is modulated with a circadian timescale, and that this modulation is strongly entrained by food. One interpretation of this finding is that the hippocampus is responsive to a food entrainable oscillator (FEO) that might modulate foraging behavior over circadian periods.

21 CFR 99.203 - Request to extend the time for completing planned studies.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Request to extend the time for completing planned... DEVICES Manufacturer's Submissions, Requests, and Applications § 99.203 Request to extend the time for... FDA under § 99.201, that FDA extend the 36-month time period for completing the studies and submitting...

21 CFR 99.203 - Request to extend the time for completing planned studies.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Request to extend the time for completing planned... DEVICES Manufacturer's Submissions, Requests, and Applications § 99.203 Request to extend the time for... FDA under § 99.201, that FDA extend the 36-month time period for completing the studies and submitting...

21 CFR 99.203 - Request to extend the time for completing planned studies.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Request to extend the time for completing planned... DEVICES Manufacturer's Submissions, Requests, and Applications § 99.203 Request to extend the time for... FDA under § 99.201, that FDA extend the 36-month time period for completing the studies and submitting...

Depression and suicidality during the postpartum period after first time deliveries, active component service women and dependent spouses, U.S. Armed Forces, 2007-2012.

PubMed

Do, Tai; Hu, Zheng; Otto, Jean; Rohrbeck, Patricia

2013-09-01

Although suicide is a leading cause of death among new mothers during the postpartum period, there has been limited research on self-harm in the postpartum period and associated risk factors. One potential risk factor for suicidality (completed suicides, suicide attempts, and suicide ideation including thoughts of self harm) during the postpartum period is postpartum depression (PPD). In this study of women who gave birth for the first time between 1 January 2007 and 31 December 2011, 5,267 (9.9% of all who delivered) active component service women and 10,301 (8.2%) dependent spouses received incident PPD diagnoses during the one year postpartum period; 213 (0.4%) service women and 221 (0.2%) dependent spouses were diagnosed with incident suicidality. After adjusting for the effects of other covariates, service women with PPD had 42.2 times the odds to be diagnosed with suicidality in the postpartum period compared to service women without PPD; dependent spouses with PPD had 14.5 times the odds compared to those without PPD. The findings of this report suggest that a history of mental disorders was common among service women and dependent spouses with PPD in the postpartum period, and, in turn, PPD was a strong predictor for suicidality in the postpartum period. These results emphasize the importance of PPD screening during the postpartum period. They also suggest that additional focused screening for suicidal behavior among those already diagnosed with PPD may be warranted.

Towards the computation of time-periodic inertial range dynamics

NASA Astrophysics Data System (ADS)

van Veen, L.; Vela-Martín, A.; Kawahara, G.

2018-04-01

We explore the possibility of computing simple invariant solutions, like travelling waves or periodic orbits, in Large Eddy Simulation (LES) on a periodic domain with constant external forcing. The absence of material boundaries and the simple forcing mechanism make this system a comparatively simple target for the study of turbulent dynamics through invariant solutions. We show, that in spite of the application of eddy viscosity the computations are still rather challenging and must be performed on GPU cards rather than conventional coupled CPUs. We investigate the onset of turbulence in this system by means of bifurcation analysis, and present a long-period, large-amplitude unstable periodic orbit that is filtered from a turbulent time series. Although this orbit is computed on a coarse grid, with only a small separation between the integral scale and the LES filter length, the periodic dynamics seem to capture a regeneration process of the large-scale vortices.

Solar cycles: A tutorial

NASA Astrophysics Data System (ADS)

Moussas, X.; Polygiannakis, J. M.; Preka-Papadema, P.; Exarhos, G.

The Sun is the nearest stellar and astrophysical laboratory, available for detailed studies in several fields of physics and astronomy. It is a sphere of hot gas with a complex and highly variable magnetic field which plays a very important role. The Sun shows an unprecedented wealth of phenomena that can be studied extensively and to the greatest detail, in a way we will never be in a position to study in other stars. Humans have studied the Sun for millennia and after the discovery of the telescope they realized that the Sun varies with time, i.e., solar activity is highly variable, in tune scales of millennia to seconds. The study of these variabilities helps us to understand how the Sun works and how it affects the interplanetary medium, Earth and the other planets. Solar power varies substantially and greatly affects the Earth and humans. Solar activity has several important periodicities, and quasi-periodicities. Knowledge of these periodicities helps us to forecast, to an extent, solar events that affect our planet. The most prominent periodicity of solar activity is the one of 11 years. The actual period is in fact 22 years because the magnetic field polarity of the Sun has to be taken into account. The Sun can be considered as a non-linear RLC electric circuit with a period of 22 years. The RLC equivalent circuit of the Sun is a van der Pol oscillator and such a model can explain many solar phenomena, including the variability of solar energy with time. Other quasi-periodicities such as the ones of 154 days, the 1.3, 1.7 to 2 years, etc., some of which might be harmonics of the 22 year cycle are also present in solar activity, and their study is very interesting and important since they affect the Earth and human activities. The period of 27 days related to solar rotation plays also a very important role in geophysical phenomena. It is noticeable that almost all periodicities are highly variable with time as wavelet analysis reveals. It is very important for humans to be in a position to forecast solar activity during the next hour, day, year, decade and century, because solar phenomena affect life on Earth and such predictions will help politicians and policy makers to better serve their countries and our planet.

Time course of motor gains induced by music-supported therapy after stroke: An exploratory case study.

PubMed

Grau-Sánchez, Jennifer; Ramos, Neus; Duarte, Esther; Särkämö, Teppo; Rodríguez-Fornells, Antoni

2017-09-01

Previous studies have shown that Music-Supported Therapy (MST) can improve the motor function and promote functional neuroplastic changes in motor areas; however, the time course of motor gains across MST sessions and treatment periods remain unknown. The aim of this study was to explore the progression of the rehabilitation of motor deficits in a chronic stroke patient for a period of 7 months. A reversal design (ABAB) was implemented in a chronic stroke patient where no treatment was provided in the A periods and MST was applied in the B periods. Each period comprised of 4 weeks and an extensive evaluation of the motor function using clinical motor tests and 3D movement analysis was performed weekly. During the MST periods, a keyboard task was recorded daily. A follow-up evaluation was performed 3 months after the second MST treatment. Improvements were observed during the first sessions in the keyboard task but clinical gains were noticeable only at the end of the first treatment and during the second treatment period. These gains were maintained in the follow-up evaluation. This is the first study examining the pattern of motor recovery progression in MST, evidencing that gradual and continuous motor improvements are possible with the repeated application of MST training. Fast-acquisition in specific motor abilities was observed at the beginning of the MST training but generalization of these improvements to other motor tasks took place at the end or when another treatment period was provided. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Transient statistics in stabilizing periodic orbits

NASA Astrophysics Data System (ADS)

Meucci, R.; Gadomski, W.; Ciofini, M.; Arecchi, F. T.

1995-11-01

The statistics of chaotic and periodic transient time intervals preceding the stabilization of a given periodic orbit have been experimentally studied in a CO2 laser with modulated losses, subjected to a small subharmonic perturbation. As predicted by the theory, an exponential tail has been found in the probability distribution of chaotic transients. Furthermore, a fine periodic structure in the distributions of the periodic transients, resulting from the interaction of the control signal and the local structure of the chaotic attractor, has been revealed.

Examining job tenure and lost-time claim rates in Ontario, Canada, over a 10-year period, 1999-2008.

PubMed

Morassaei, Sara; Breslin, F Curtis; Shen, Min; Smith, Peter M

2013-03-01

We sought to examine the association between job tenure and lost-time claim rates over a 10-year period in Ontario, Canada. Data were obtained from workers' compensation records and labour force survey data from 1999 to 2008. Claim rates were calculated for gender, age, industry, occupation, year and job tenure group. A multivariate analysis and examination of effect modification were performed. Differences in injury event and source of injury were also examined by job tenure. Lost-time claim rates were significantly higher for workers with shorter job tenure, regardless of other factors. Claim rates for new workers differed by gender, age and industry, but remained relatively constant at an elevated rate over the observed time period. This study is the first to examine lost-time claim rates by job tenure over a time period during which overall claim rates generally declined. Claim rates did not show a convergence by job tenure. Findings highlight that new workers are still at elevated risk, and suggest the need for improved training, reducing exposures among new workers, promoting permanent employment, and monitoring work injury trends and risk factors.

Exposure to Ambient Particulate Matter during Specific Gestational Periods Produces Adverse Obstetric Consequences in Mice

PubMed Central

Blum, Jason L.; Chen, Lung-Chi

2017-01-01

Background: Epidemiological studies associate inhalation of fine-sized particulate matter (PM2.5) during pregnancy with preterm birth (PTB) and low birth weight (LBW) but disagree over which time frames are most sensitive, or if effects are cumulative. Objectives: Our objective was to provide experimental plausibility for epidemiological observations by testing the hypothesis that exposure to PM2.5 during discrete periods of pregnancy results in PTB and LBW. Methods: For the first study, timed-pregnant B6C3F1 mice were exposed to concentrated ambient PM2.5 (CAPs) or filtered air (FA) throughout pregnancy [6 h/d from gestational day (GD) 0.5 through GD16.5]. A follow-up study examined the effects of CAPs exposure during discrete gestational periods (1: GD0.5–5.5; 2: GD6.5–14.5; 3: GD14.5–16.5; 4: GD0.5–16.5) aligning to milestones during human development. Results: In the first experiment, exposure to 160 μg CAPs/m3 throughout pregnancy decreased gestational term by 0.5 d (∼1.1  wk decrease for humans) and birth weight by 11.4% compared with FA. The follow-up experiment investigated timing of CAPs exposure (mean concentrations at 178, 193, 171, and 173 μg/m3 for periods 1–4, respectively). Pregnancy was significantly shortened (vs. FA) by ∼0.4d when exposure occurred during gestational periods 2 and 4, and by ∼0.5d if exposure occurred during period 3. Exposure during periods 1, 2, and 4 reduced birth weight by ∼10% compared with FA, and placental weight was reduced (∼8%) on GD17.5 if exposure occurred only during period 3. Conclusions: Adverse PM2.5-induced outcomes such as PTB and LBW are dependent upon the periods of maternal exposure. The results of these experimental studies could contribute significantly to air pollution policy decisions in the future. https://doi.org/10.1289/EHP1029 PMID:28893721

Postpartum follow-up: can psychosocial support reduce newborn readmissions?

PubMed

Barilla, Dora; Marshak, Helen Hopp; Anderson, S Eric; Hopp, Joyce W

2010-01-01

To determine whether there was a relationship between postpartum psychosocial support from healthcare providers and the rate of normal newborn readmissions (NNRs), and whether there was a cost benefit to justify an intervention. Data were abstracted for all normal newborn births from 1999 to 2006 (N = 14,786) at a community hospital in southern California at three different time periods: (1) at baseline prior to any intervention (1999-2000), (2) the 4 years during the comprehensive psychosocial support intervention (2001-2004), and (3) the 2 years during a limited psychosocial support intervention (2004-2006). A cost-benefit analysis was performed to analyze whether the financial benefits from the intervention matched or exceeded the costs for NNRs. There was a significantly lower readmission rate of 1.0% (p = < .001) during the comprehensive intervention time period compared to baseline (2.3%) or to the limited intervention time period (2.3%). Although there was no significant difference in the average cost per newborn readmitted across the three study time periods, during the comprehensive intervention time period the average costs of a NNR were significantly lower ($4,180, p = .041) for the intervention group compared to those who received no intervention ($5,338). There was a cost benefit of 513,540 dollars due to fewer readmissions during the comprehensive time period, but it did not exceed the cost of the intervention. Providing comprehensive follow-up for new mothers in the postpartum period can reduce NNRs, thus lowering the average newborn readmission costs for those who receive psychosocial support. Followup for new mothers should be an accepted norm rather than the exception in postpartum care, but NNRs should not be considered the sole outcome in such programs.

Nonequilibrium steady states and resonant tunneling in time-periodically driven systems with interactions

NASA Astrophysics Data System (ADS)

Qin, Tao; Hofstetter, Walter

2018-03-01

Time-periodically driven systems are a versatile toolbox for realizing interesting effective Hamiltonians. Heating, caused by excitations to high-energy states, is a challenge for experiments. While most setups so far address the relatively weakly interacting regime, it is of general interest to study heating in strongly correlated systems. Using Floquet dynamical mean-field theory, we study nonequilibrium steady states (NESS) in the Falicov-Kimball model, with time-periodically driven kinetic energy or interaction. We systematically investigate the nonequilibrium properties of the NESS. For a driven kinetic energy, we show that resonant tunneling, where the interaction is an integer multiple of the driving frequency, plays an important role in the heating. In the strongly correlated regime, we show that this can be well understood using Fermi's golden rule and the Schrieffer-Wolff transformation for a time-periodically driven system. We furthermore demonstrate that resonant tunneling can be used to control the population of Floquet states to achieve "photodoping." For driven interactions introduced by an oscillating magnetic field near a widely adopted Feshbach resonance, we find that the double occupancy is strongly modulated. Our calculations apply to shaken ultracold-atom systems and to solid-state systems in a spatially uniform but time-dependent electric field. They are also closely related to lattice modulation spectroscopy. Our calculations are helpful to understand the latest experiments on strongly correlated Floquet systems.

Is it possible to predict long-term success with k-NN? Case study of four market indices (FTSE100, DAX, HANGSENG, NASDAQ)

NASA Astrophysics Data System (ADS)

Shi, Y.; Gorban, A. N.; Y Yang, T.

2014-03-01

This case study tests the possibility of prediction for 'success' (or 'winner') components of four stock & shares market indices in a time period of three years from 02-Jul-2009 to 29-Jun-2012.We compare their performance ain two time frames: initial frame three months at the beginning (02/06/2009-30/09/2009) and the final three month frame (02/04/2012-29/06/2012).To label the components, average price ratio between two time frames in descending order is computed. The average price ratio is defined as the ratio between the mean prices of the beginning and final time period. The 'winner' components are referred to the top one third of total components in the same order as average price ratio it means the mean price of final time period is relatively higher than the beginning time period. The 'loser' components are referred to the last one third of total components in the same order as they have higher mean prices of beginning time period. We analyse, is there any information about the winner-looser separation in the initial fragments of the daily closing prices log-returns time series.The Leave-One-Out Cross-Validation with k-NN algorithm is applied on the daily log-return of components using a distance and proximity in the experiment. By looking at the error analysis, it shows that for HANGSENG and DAX index, there are clear signs of possibility to evaluate the probability of long-term success. The correlation distance matrix histograms and 2-D/3-D elastic maps generated from ViDaExpert show that the 'winner' components are closer to each other and 'winner'/'loser' components are separable on elastic maps for HANGSENG and DAX index while for the negative possibility indices, there is no sign of separation.

Effects of food availability and climate on activity patterns of western black-crested gibbons in an isolated forest fragment in southern Yunnan, China.

PubMed

Ni, Qingyong; Xie, Meng; Grueter, Cyril C; Jiang, Xuelong; Xu, Huailiang; Yao, Yongfang; Zhang, Mingwang; Li, Yan; Yang, Jiandong

2015-10-01

The critically endangered western black-crested gibbon (Nomascus concolor) is distributed in isolated habitat fragments in northern Vietnam, northwestern Laos, and southwestern China. To assess the behavioral adaptation of this species to forest fragments and its response to seasonal variation in food availability and climate, we present activity patterns of a group inhabiting an isolated forest based on two year-long studies in southern Yunnan, China. Annually, the gibbons spent nearly half of their active time resting, followed by moving and feeding. In both study periods, the time allocated to activities varied significantly between months, and was affected by food availability and climate factors. The group delayed retirement when tree fruit was abundant, and they decreased time spent moving and playing during periods of low fruit availability. In the cold months, the gibbons decreased time spent moving, and they decreased active time and resting time when rainfall was high. The results suggest that the group may seek to maximize net energy intake like energy maximizers when high quality food is most available, and adopt an energy-conserving strategy during periods of lower food availability and temperature. The gibbons showed similar diurnal variation in activity patterns to a group inhabiting a continuous forest at Dazhaizi, Mt. Wuliang, central Yunnan. However, they had a longer active period, and devoted more time to resting but less time to feeding. The individuals also spent lower percentages of time engaged in social behavior than those at Dazhaizi. These differences may be due to their smaller home range and unusual group composition caused by habitat fragmentation.

Inactivation/reactivation of antibiotic-resistant bacteria by a novel UVA/LED/TiO2 system.

PubMed

Xiong, Pei; Hu, Jiangyong

2013-09-01

In this study, an effective photocatalytic disinfection system was established using the newly emerged high power UVA/LED lamp. Crystallizing dish coated with TiO2 was prepared by 32-times impregnation-drying processes, and served as the supporting container for water samples. This study focused on the application of this UVA/LED system for the photocatalytic disinfection of selected antibiotic-resistant bacteria, Escherichia coli ATCC 700891. The disinfection performances were studied under various light intensities and illumination modes. Results show that higher light intensity could reach more significant inactivation of E. coli ATCC 700891. With the same UV dose, log-removal of antibiotic-resistant bacteria decreased with circle time in the studied range, while increased with duty circle. A "residual disinfecting effect" was found in the following dark period for bacteria collected at different phases of photocatalytic process. Residual disinfecting effect was found not significant for bacteria with 30 min periodic illumination. While residual disinfecting effect could kill almost all bacteria after 90 min UV periodic illumination within the following 240 min dark period. Copyright © 2013 Elsevier Ltd. All rights reserved.

Brisk walking can promote functional recovery in chronic stroke patients.

PubMed

Batcho, Charles Sèbiyo; Stoquart, Gaëtan; Thonnard, Jean-Louis

2013-09-01

To determine whether regular brisk walking can promote functional recovery in community-dwelling stroke patients. A total of 44 chronic stroke patients, recruited in Belgium and Benin, respectively European high-income and African low-income countries. This longitudinal, single-cohort, observational study with 1 intervention period and 4 time-points of assessments (2 baseline, 1 post-intervention and 1 follow-up) was structured in 3 periods: pre-intervention period (1 month), intervention period (3 months) and follow-up period (3 month). Intervention consisted of a 3 times/week group-based brisk walking programme. Primary outcome measures were ACTIVLIM-Stroke questionnaire and the 6-minute walk test (6MWT). Secondary outcome measures were the Stroke Impairment Assessment Set (SIAS), the Hospital Anxiety and Depression Scale (HADS), and the Berg Balance Scale (BBS). All outcome measures were stable during the pre-intervention period (p ≥ 0.16). They all improved significantly after intervention (p ≤ 0.01), except the HADS (p = 0.058). However, during the follow-up period, SIAS (p = 0.002) and BBS (p = 0.001) decreased, while ACTIVLIM-Stroke, 6MWT and HADS showed no significant change (p ≥ 0.13). This study suggests regular brisk walking as an effective approach to promote functional recovery in chronic stroke survivors. However, further studies are required before generalizing these results to the whole stroke population.

An Analytical Time–Domain Expression for the Net Ripple Produced by Parallel Interleaved Converters

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

Johnson, Brian B.; Krein, Philip T.

We apply modular arithmetic and Fourier series to analyze the superposition of N interleaved triangular waveforms with identical amplitudes and duty-ratios. Here, interleaving refers to the condition when a collection of periodic waveforms with identical periods are each uniformly phase-shifted across one period. The main result is a time-domain expression which provides an exact representation of the summed and interleaved triangular waveforms, where the peak amplitude and parameters of the time-periodic component are all specified in closed-form. Analysis is general and can be used to study various applications in multi-converter systems. This model is unique not only in that itmore » reveals a simple and intuitive expression for the net ripple, but its derivation via modular arithmetic and Fourier series is distinct from prior approaches. The analytical framework is experimentally validated with a system of three parallel converters under time-varying operating conditions.« less

Optimal recall period in assessing the adherence to antihypertensive therapy: a pilot study.

PubMed

Doró, Péter; Benko, Ria; Czakó, Anikó; Matuz, Mária; Thurzó, Ferenc; Soós, Gyöngyvér

2011-08-01

To evaluate the validity of patient self-reported adherence, and to find the optimal length of recall period which best reflects the long-term adherence pattern of the patient. Patients were recruited from a general practitioner's practice in a Hungarian town. In this prospective study 30 patients, who had already been on antihypertensive treatment, were involved. The study was designed to monitor one antihypertensive medication per patient for 3 months. Patients received a 3-month supply of one antihypertensive medication in an electronic Medication Event Monitoring System (MEMS). At the end of the study period patients completed a structured questionnaire regarding their medication taking behavior during the last 7, 14 and 30 days. The results measured with MEMS were considered as the reference value, and other measures were compared using the Bland-Altman method. Self-reported adherence, length of recall period, taking adherence and timing adherence measured by MEMS. Of the 30 patients included, 29 patients (13 males and 16 females) completed the study. The mean age of the patients was 60.6 years, ranging between 36 and 86 years. Patients were monitored for an average of 89 days (ranging between 49 and 106 days). Fifteen patients were on once daily, 9 patients were on twice daily, and 5 patients were on 3 times daily dosing schedule. The total expected number of medication taking events was 4,281. The MEMS caps recorded a total of 4,071 openings, which showed only a 3.56% deviation from the pill counts of the remaining tablets. The overall taking adherence was 95.1%, timing adherence was 75.2%. Patients' adherence report using a visual analog scale and reporting the number of missed doses became more accurate as the length of the recall period increased. Increased number of chronically taken medications was associated with better adherence. Increased dosing frequency of the observed antihypertensive medication resulted in decreased adherence. The results showed that the length of the recall period influences the accuracy of self-reported adherence. Patients seem to be able to report more precisely their medication taking behavior regarding a 30 day period than a 7 day period.

Prevention of Hamstring Injuries in Collegiate Sprinters

PubMed Central

Sugiura, Yusaku; Sakuma, Kazuhiko; Sakuraba, Keishoku; Sato, Yamato

2017-01-01

Background: No studies have been reported on how strength, agility, and flexibility training reduce the occurrence of hamstring injuries in sprinters. Therefore, a program for preventing hamstring injury in these athletes has not been established. Purpose: To document the incidence of hamstring injuries during times when different prevention strategies were employed to see whether a particular prevention program reduced their occurrence. Study Design: Descriptive epidemiology study. Methods: The study subjects were a total of 613 collegiate male sprinters trained by the same coach over 24 seasons. Tow training was used throughout the research period as a normal sprint training method. The hamstring injury prevention program evolved over time. From 1988 to 1991 (period 1), prevention focused on strength training alone; from 1992 to 1999 (period 2), a combination of strength and agility training was used; and from 2000 to 2011 (period 3), the program incorporated strength, agility, and flexibility training. The incidence of hamstring injuries was compared for each of the 3 prevention strategies. Results: The incidence of hamstring injuries per athlete-seasons was 137.9 for period 1, 60.6 for period 2, and 6.7 for period 3. A significant difference was observed in the incidence of hamstring injury according to the different prevention programs (χ2(2) = 31.78, P < .001, effect size: Cramer V = 0.23, 1 − β = 0.999). Residual analysis showed that the number of hamstring injuries for period 1 was significantly greater than the expected value (P < .01), whereas that for period 3 was significantly lower than the expected value (P < .01). Conclusion: The incidence of hamstring injuries in sprinters decreased as agility and flexibility were added to strength training. PMID:28210652

Effects of Sparring Load on Reaction Speed and Punch Force During the Precompetition and Competition Periods in Boxing.

PubMed

Hukkanen, Esa; Häkkinen, Keijo

2017-06-01

Seven, male, national-level boxers (age, 20.3 ± 2.7 years; height, 1.80 ± 0.06 m; mass, 73.8 ± 11.1 kg) participated in this study to investigate the effects of sparring on reaction time and punch force of straight punches measured during the precompetition and competition periods. Heart rate and blood lactate concentrations were also monitored. Sparring load was chosen in accordance with the current rules: 3 × 3-minute bouts with 1-minute break in between. Reaction time of rear straight lengthened (p < 0.01) during the sparring load of the precompetition period after the third round (to 390 milliseconds) in comparison to the competition period (to 310 milliseconds). Reaction time of lead straight lengthened (p ≤ 0.05) between the first and third round during the precompetition with no differences during the competition period. Both rear and lead straight punch forces were greater at all measurement points during the precompetition compared with the competition period. Punch forces increased for both rear and lead straight between the first and third rounds with the highest forces after third round during the precompetition (rear straight, 209 kg) and competition (rear straight, 176 kg) periods. Blood lactate levels increased after every round during both periods being at its greatest after the third round (17 mmol·L during the precompetition and 13 mmol·L during the competition period). The present sparring-induced differences in reaction time and punch forces of straight punches during the precompetition compared with the competition period may be the result of different volume and intensity of training with different goals in boxing-specific and explosive strength training.

Dalfampridine Effects Beyond Walking Speed in Multiple Sclerosis

PubMed Central

Fjeldstad, Cecilie; Suárez, Gustavo; Klingler, Michael; Henney, Herbert R.; Rabinowicz, Adrian L.

2015-01-01

Background: Dalfampridine extended release (ER) improves walking in people with multiple sclerosis (MS), as demonstrated by walking speed improvement. This exploratory study evaluated treatment effects of dalfampridine-ER on gait, balance, and walking through treatment withdrawal and reinitiation. Methods: Dalfampridine-ER responders, based on Timed 25-Foot Walk (T25FW) assessment before study entry, were included in this open-label, three-period, single-center study. Period 1: on-drug evaluations performed at screening and 1 week after screening. Period 2: dalfampridine-ER withdrawal and off-drug evaluations (days 5 and 11). Period 3: dalfampridine-ER reinitiation/final on-drug evaluation (day 15). Primary outcome variables: NeuroCom composite scores for gait and balance; balance was evaluated if gait changes were significant. Secondary variables: individual NeuroCom scores, walking speed (T25FW) and distance (2-Minute Walk Test [2MWT]), and balance (Berg Balance Scale [BBS]). Results: All 20 patients completed the study: mean age, 53.1 years; mean MS duration, 11.3 years; mean time taking dalfampridine-ER, 315.3 days. NeuroCom gait composite scores worsened during period 2 relative to period 1 and improved during period 3; the mean ± SD difference in gait composite scores on drug was 4.03 ± 1.51 points (P = .015). Balance composite scores did not change significantly. Improvements were observed for off-drug versus on-drug for T25FW (0.36 ft/sec, P < .001), 2MWT (25.4 ft, P = .006), and BBS (1.7 points, P = .003). Safety profile was consistent with previous studies. Conclusions: Significant improvements in gait, walking speed, distance, and balance were demonstrated by dalfampridine-ER reinitiation after a 10-day withdrawal period. PMID:26664333

Effect of exercise timing on elevated postprandial glucose levels.

PubMed

Hatamoto, Yoichi; Goya, Ryoma; Yamada, Yosuke; Yoshimura, Eichi; Nishimura, Sena; Higaki, Yasuki; Tanaka, Hiroaki

2017-08-01

There is no consensus regarding optimal exercise timing for reducing postprandial glucose (PPG). The purpose of the present study was to determine the most effective exercise timing. Eleven participants completed four different exercise patterns 1 ) no exercise; 2 ) preprandial exercise (jogging); 3 ) postprandial exercise; and 4 ) brief periodic exercise intervention (three sets of 1-min jogging + 30 s of rest, every 30 min, 20 times total) in a random order separated by a minimum of 5 days. Preprandial and postprandial exercise consisted of 20 sets of intermittent exercise (1 min of jogging + 30 s rest per set) repeated 3 times per day. Total daily exercise volume was identical for all three exercise patterns. Exercise intensities were 62.4 ± 12.9% V̇o 2peak Blood glucose concentrations were measured continuously throughout each trial for 24 h. After breakfast, peak blood glucose concentrations were lower with brief periodic exercise (99 ± 6 mg/dl) than those with preprandial and postprandial exercise (109 ± 10 and 115 ± 14 mg/dl, respectively, P < 0.05, effect size = 0.517). After lunch, peak glucose concentrations were lower with brief periodic exercise than those with postprandial exercise (97 ± 5 and 108 ± 8 mg/dl, P < 0.05, effect size = 0.484). After dinner, peak glucose concentrations did not significantly differ among exercise patterns. Areas under the curve over 24 h and 2 h postprandially did not differ among exercise patterns. These findings suggest that brief periodic exercise may be more effective than preprandial and postprandial exercise at attenuating PPG in young active individuals. NEW & NOTEWORTHY This was the first study to investigate the effect of different exercise timing (brief periodic vs. preprandial vs. postprandial exercise) on postprandial glucose (PPG) attenuation in active healthy men. We demonstrated that brief periodic exercise attenuated peak PPG levels more than preprandial and postprandial exercise, particularly in the morning. Additionally, PPG rebounded soon after discontinuing postprandial exercise. Thus, brief periodic exercise may be better than preprandial and postprandial exercise at attenuating PPG levels. Copyright © 2017 the American Physiological Society.

An active video game intervention does not improve physical activity and sedentary time of children at-risk for developmental coordination disorder: a crossover randomized trial.

PubMed

Howie, E K; Campbell, A C; Straker, L M

2016-03-01

Children with developmental coordination disorder (DCD) are highly inactive and sedentary. The purpose of this study was to assess the impact of a home-based active video game intervention on objectively measured physical activity and sedentary behaviour in children at risk for DCD. In a crossover randomized clinical trial, 21 children (mean age 11.0, SD 1.0; n = 11 girls) in Perth, Western Australia participated in two 16-week periods: no active video games (AVGs) control period and AVGs intervention period. Two active input consoles were provided to participants along with a selection of non-violent AVGs for participants to play at home. Participants wore accelerometers at baseline and following each period to determine minutes of sedentary, light, moderate and vigorous times in addition to self-reported types of activities in a diary. Linear mixed models, adjusted for the order of periods, compared physical activity and sedentary time during the last week of each period. There were no significant differences between the intervention and control periods in time spent in sedentary (decrease of -1.0 min/day during the intervention period, 95%CI -12.1, 10.1), light (increase of 2.2 min/day, 95%CI -8.8, 13.2), moderate (decrease of 0.7 min/day, 95%CI -4.6, 3.3) or vigorous (decrease of -0.6 min/day, 95%CI -1.6, 0.4). Among children at risk for DCD, participating in this AVG intervention did not improve objectively measured physical activity and sedentary time. © 2015 John Wiley & Sons Ltd.

A comparison of time-shared vs. batch development of space software

NASA Technical Reports Server (NTRS)

Forthofer, M.

1977-01-01

In connection with a study regarding the ground support software development for the Space Shuttle, an investigation was conducted concerning the most suitable software development techniques to be employed. A time-sharing 'trial period' was used to determine whether or not time-sharing would be a cost-effective software development technique for the Ground Based Shuttle system. It was found that time-sharing substantially improved job turnaround and programmer access to the computer for the representative group of ground support programmers. Moreover, this improvement resulted in an estimated saving of over fifty programmer days during the trial period.

Method of Heat Treating Aluminum-Lithium Alloy to Improve Formability

NASA Technical Reports Server (NTRS)

Russell, Carolyn Kurgan (Inventor); Chen, Po-Shou (Inventor)

2016-01-01

A method is provided for heat treating aluminum-lithium alloys to improve their formability. The alloy is heated to a first temperature, maintained at the first temperature for a first time period, heated at the conclusion of the first time period to a second temperature, maintained at the second temperature for a second time period, actively cooled at the conclusion of the second time period to a third temperature, maintained at the third temperature for a third time period, and then passively cooled at the conclusion of the third time period to room temperature.

43 CFR 45.3 - How are time periods computed?

Code of Federal Regulations, 2010 CFR

2010-10-01

... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false How are time periods computed? 45.3... IN FERC HYDROPOWER LICENSES General Provisions § 45.3 How are time periods computed? (a) General. Time periods are computed as follows: (1) The day of the act or event from which the period begins to...

The effect of substrate composition and storage time on urine specific gravity in dogs.

PubMed

Steinberg, E; Drobatz, K; Aronson, L

2009-10-01

The purpose of this study is to evaluate the effects of substrate composition and storage time on urine specific gravity in dogs. A descriptive cohort study of 15 dogs. The urine specific gravity of free catch urine samples was analysed during a 5-hour time period using three separate storage methods; a closed syringe, a diaper pad and non-absorbable cat litter. The urine specific gravity increased over time in all three substrates. The syringe sample had the least change from baseline and the diaper sample had the greatest change from baseline. The urine specific gravity for the litter and diaper samples had a statistically significant increase from the 1-hour to the 5-hour time point. The urine specific gravity from canine urine stored either on a diaper or in a non-absorbable litter increased over time. Although the change was found to be statistically significant over the 5-hour study period it is unlikely to be clinically significant.

Aquatic Exercises were Associated with an Acceptable State of Symptoms in Patients with Inflammatory Rheumatic Diseases: Results from a Study with Interrupted Time-Series Design.

PubMed

Christie, Anne; Hagen, Kåre Birger; Mowinckel, Petter; Dagfinrud, Hanne

2014-12-10

The aim of this study was two-fold: to compare symptoms and daily activity in patients with inflammatory rheumatic diseases across periods with and without aquatic exercises, and to examine whether the patients reached an acceptable state of symptoms during the periods with aquatic exercises. Thirty-six patients reported pain, fatigue, stiffness and ability to carry out daily activities across periods with and without aquatic exercises. The study has an interrupted time-series design and variables were collected with text messages on mobile phones twice a week over a period of 35 weeks. There was a significant reduction in pain, fatigue, stiffness and enhanced level of daily activity (p > 0.05) during periods of aquatic exercises compared to periods without. Further, a significantly higher proportion of patients reached an acceptable state for both pain and fatigue during periods with aquatic exercises. Living with an inflammatory rheumatic disease is a lifelong challenge. Pain and fatigue are considered major obstacles for daily functioning and adequate self-management strategies are requested. Based on the high proportion of patients reporting to be in an acceptable state of both pain and fatigue during periods with aquatic exercises, the intervention should be regarded as an important self-management tool rather than a treatment option assuming long-lasting effects. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.

Spatiotemporal variation of the association between climate dynamics and HFRS outbreaks in Eastern China during 2005-2016 and its geographic determinants

PubMed Central

Wu, Jiaping; Cazelles, Bernard; Qian, Quan; Mu, Di; Wang, Yong; Yin, Wenwu; Zhang, Wenyi

2018-01-01

Background Hemorrhagic fever with renal syndrome (HFRS) is a rodent-associated zoonosis caused by hantavirus. The HFRS was initially detected in northeast China in 1931, and since 1955 it has been detected in many regions of the country. Global climate dynamics influences HFRS spread in a complex nonlinear way. The quantitative assessment of the spatiotemporal variation of the “HFRS infections-global climate dynamics” association at a large geographical scale and during a long time period is still lacking. Methods and findings This work is the first study of a recently completed dataset of monthly HFRS cases in Eastern China during the period 2005–2016. A methodological synthesis that involves a time-frequency technique, a composite space-time model, hotspot analysis, and machine learning is implemented in the study of (a) the association between HFRS incidence spread and climate dynamics and (b) the geographic factors impacting this association over Eastern China during the period 2005–2016. The results showed that by assimilating core and city-specific knowledge bases the synthesis was able to depict quantitatively the space-time variation of periodic climate-HFRS associations at a large geographic scale and to assess numerically the strength of this association in the area and period of interest. It was found that the HFRS infections in Eastern China has a strong association with global climate dynamics, in particular, the 12, 18 and 36 mos periods were detected as the three main synchronous periods of climate dynamics and HFRS distribution. For the 36 mos period (which is the period with the strongest association), the space-time correlation pattern of the association strength indicated strong temporal but rather weak spatial dependencies. The generated space-time maps of association strength and association hotspots provided a clear picture of the geographic variation of the association strength that often-exhibited cluster characteristics (e.g., the south part of the study area displays a strong climate-HFRS association with non-point effects, whereas the middle-north part displays a weak climate-HFRS association). Another finding of this work is the upward climate-HFRS coherency trend for the past few years (2013–2015) indicating that the climate impacts on HFRS were becoming increasingly sensitive with time. Lastly, another finding of this work is that geographic factors affect the climate-HFRS association in an interrelated manner through local climate or by means of HFRS infections. In particular, location (latitude, distance to coastline and longitude), grassland and woodland are the geographic factors exerting the most noticeable effects on the climate-HFRS association (e.g., low latitude has a strong effect, whereas distance to coastline has a wave-like effect). Conclusions The proposed synthetic quantitative approach revealed important aspects of the spatiotemporal variation of the climate-HFRS association in Eastern China during a long time period, and identified the geographic factors having a major impact on this association. Both findings could improve public health policy in an HFRS-torn country like China. Furthermore, the synthetic approach developed in this work can be used to map the space-time variation of different climate-disease associations in other parts of China and the World. PMID:29874263

Methods, systems and devices for detecting and locating ferromagnetic objects

DOEpatents

Roybal, Lyle Gene [Idaho Falls, ID; Kotter, Dale Kent [Shelley, ID; Rohrbaugh, David Thomas [Idaho Falls, ID; Spencer, David Frazer [Idaho Falls, ID

2010-01-26

Methods for detecting and locating ferromagnetic objects in a security screening system. One method includes a step of acquiring magnetic data that includes magnetic field gradients detected during a period of time. Another step includes representing the magnetic data as a function of the period of time. Another step includes converting the magnetic data to being represented as a function of frequency. Another method includes a step of sensing a magnetic field for a period of time. Another step includes detecting a gradient within the magnetic field during the period of time. Another step includes identifying a peak value of the gradient detected during the period of time. Another step includes identifying a portion of time within the period of time that represents when the peak value occurs. Another step includes configuring the portion of time over the period of time to represent a ratio.

Trends in infective endocarditis hospitalisations at United States children's hospitals from 2003 to 2014: impact of the 2007 American Heart Association antibiotic prophylaxis guidelines.

PubMed

Bates, Katherine E; Hall, Matthew; Shah, Samir S; Hill, Kevin D; Pasquali, Sara K

2017-05-01

National organisations in several countries have recently released more restrictive guidelines for infective endocarditis prophylaxis, including the American Heart Association 2007 guidelines. Initial studies demonstrated no change in infective endocarditis rates over time; however, a recent United Kingdom study suggested an increase; current paediatric trends are unknown. Children (5 years of age. Interrupted time series analysis was used to evaluate rates over time indexed to total hospitalisations. A total of 841 cases were identified. The median age was 13 years (interquartile range 9-15 years). In the pre-guideline period, there was a slight increase in the rate of infective endocarditis by 0.13 cases/10,000 hospitalisations per semi-annual period. In the post-guideline period, the rate of infective endocarditis increased by 0.12 cases/10,000 hospitalisations per semi-annual period. There was no significant difference in the rate of change in the pre- versus post-guidelines period (p=0.895). Secondary analyses in children >5 years of age with CHD and in children hospitalised with any type of infective endocarditis at any age revealed similar results. We found no significant change in infective endocarditis hospitalisation rates associated with revised prophylaxis guidelines over 11 years across 29 United States children's hospitals.

Dilations of anastomotic strictures over time after repair of esophageal atresia.

PubMed

Stenström, Pernilla; Anderberg, Magnus; Börjesson, Anna; Arnbjörnsson, Einar

2017-02-01

Anastomotic strictures commonly occur in patients undergoing surgery for esophageal atresia (EA). The primary aim of this study was to determine the age distribution of dilation procedures for anastomotic strictures over the patient's childhood after reconstruction of EA. The secondary aim was to evaluate the effect of postoperative proton pump inhibitors (PPIs) on the frequency of dilations. This observational study was conducted at a single tertiary center of pediatric surgery. The times that dilations of strictures were performed were assessed during three study periods: 1983-1995, 2001-2009, and 2010-2014. PPIs were not used during the first period, and then, respectively, for 3 and 12 months postoperatively. The indications for dilation were signs of obstruction and/or radiological signs of stricture. A total of 131 children underwent esophageal reconstruction, and of those, 60 (46%) required at least 1 dilation procedure for strictures. There were no differences in the frequencies of dilation procedures between the three study periods (28/66, 18/32 and 14/33, respectively; P = 0.42). The overall median number of dilations per patient was 3 (range 1-21) with no differences between the study periods. The differences between ages at which the first dilation was performed during each study period were significant, as follows: 7, 2, and 8 months, respectively (P = 0.03). Fiftyone percent of all dilation procedures were performed during the first year of life, 16% during the second year, and 33% during years 2-15. Four children (2%) underwent >12 dilations. The first year of life was the time of greatest need for dilation of AS after reconstruction of EA; however, dilations were also performed several years later. PPIs did not affect the frequency of dilations during the first year of life.

A statistical study of merging galaxies: Theory and observations

NASA Technical Reports Server (NTRS)

Chatterjee, Tapan K.

1990-01-01

A study of the expected frequency of merging galaxies is conducted, using the impulsive approximation. Results indicate that if we consider mergers involving galaxy pairs without halos in a single crossing time or orbital period, the expected frequency of mergers is two orders of magnitude below the observed value for the present epoch. If we consider mergers involving several orbital periods or crossing times, the expected frequency goes up by an order of magnitude. Preliminary calculation indicate that if we consider galaxy mergers between pairs with massive halos, the merger is very much hastened.

People's preference patterns for gains/losses in multiple time period situations.

PubMed

Chang, Shin-Shin; Chang, Jung-Hua

2013-10-01

Little research to date has been devoted to investigating whether people treat time differently from money when facing multiple gains or losses. This study tested the hypothesis that because time is characterized by perishability, fixed supply, and infungibility, people with strong motivation to obtain a long period of uninterrupted discretionary time would strive to trim the time needed for non-discretionary activities or to combine several non-discretionary activities. As a result, people prefer integration over segregation of multiple time losses or gains, which is not consistent with the prediction based on hedonic editing theory or the renewable resource model. This proposition is supported by results from four experiments.

A comparative study of electric load curve changes in an urban low-voltage substation in Spain during the economic crisis (2008-2013).

PubMed

Lara-Santillán, Pedro M; Mendoza-Villena, Montserrat; Fernández-Jiménez, L Alfredo; Mañana-Canteli, Mario

2014-01-01

This paper presents a comparative study of the electricity consumption (EC) in an urban low-voltage substation before and during the economic crisis (2008-2013). This low-voltage substation supplies electric power to near 400 users. The EC was measured for an 11-year period (2002-2012) with a sampling time of 1 minute. The study described in the paper consists of detecting the changes produced in the load curves of this substation along the time due to changes in the behaviour of consumers. The EC was compared using representative curves per time period (precrisis and crisis). These representative curves were obtained after a computational process, which was based on a search for days with similar curves to the curve of a determined (base) date. This similitude was assessed by the proximity on the calendar, day of the week, daylight time, and outdoor temperature. The last selection parameter was the error between the nearest neighbour curves and the base date curve. The obtained representative curves were linearized to determine changes in their structure (maximum and minimum consumption values, duration of the daily time slot, etc.). The results primarily indicate an increase in the EC in the night slot during the summer months in the crisis period.

Homologous and Homologous like Microwave Solar Radio Bursts

NASA Astrophysics Data System (ADS)

Trevisan, R. H.; Sawant, H. S.; Kalman, B.; Gesztelyi, L.

1990-11-01

ABSTRACT. Solar radio observations at 1.6 GHz were carried out in the month of July, 1985 by using 13.7 m diameter Itapetinga antenna with time resolution of 3 ms. Homologous Bursts, with total duration of about couple of seconds and repeated by some seconds were observed associated with Homologous H- flares. These H- flares were having periodicities of about 40 min. Observed long periodicities were attributed to oscillation of prominences, and small periods were attributed to removal of plasma from the field interaction zone. Also observed are "Homologous-Like" bursts. These bursts are double peak bursts with same time profile repeating in time. In addition to this, the ratio of the total duration of the bursts to time difference in the peaks of bursts remain constant. Morphological studies of these bursts have been presented. Keq tuoit : SUN-BURSTS - SUN-FLARE

Dynamic regimes of local homogeneous population model with time lag

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

Neverova, Galina; Frisman, Efim

We investigated Moran - Ricker model with time lag 1. It is made analytical and numerical study of the model. It is shown there is co-existence of various dynamic regimes under the same values of parameters. The model simultaneously possesses several different limit regimes: stable state, periodic fluctuations, and chaotic attractor. The research results show if present population size substantially depends on population number of previous year then it is observed quasi-periodic oscillations. Fluctuations with period 2 occur when the growth of population size is regulated by density dependence in the current year.

Estimation of ion charge states using Van Allen Probes-RBSPICE: a case study

NASA Astrophysics Data System (ADS)

Farinas Perez, G.; Sibeck, D. G.

2017-12-01

We use data from the RBSPICE instrument aboard the Van Allen Probes spacecraft to identify particle injection events with ion drift echoes. We calculate the arrival time and drift period of the protons, helium and oxygen for every energy channel of the RBSPICE instrument. The ions drift period depends upon their energy and charge, as we know the particle energy and the time drift period, the charge state can be estimated for a dipolar magnetic field model. A drift-echo event occurred in May 23, 2013 at 0400 UT is analyzed.

IMS/Satellite Situation Center report. Predicted orbit plots for Vela 5B, 1976

NASA Technical Reports Server (NTRS)

1975-01-01

Predicted orbit plots for the Vela 5B satellite are presented for the time period January-December 1976. This satellite has been identified as an important possible contributor to the International Magnetospheric Study (IMS) project. The predicted orbit plots are shown in three projections. The time period covered by each set of projections is 4 days 16 hours, corresponding approximately to the period of Vela 5B. The three coordinate systems used are the Geocentric Solar Ecliptic system (GSE), the Geocentric Solar Magnetospheric system (GSM), and the Solar Magnetic system (SM).

Climate, canopy disturbance, and radial growth averaging in a second-growth mixed-oak forest in West Virginia, USA

Treesearch

James S. Rentch; B. Desta Fekedulegn; Gary W. Miller

2002-01-01

This study evaluated the use of radial growth averaging as a technique of identifying canopy disturbances in a thinned 55-year-old mixed-oak stand in West Virginia. We used analysis of variance to determine the time interval (averaging period) and lag period (time between thinning and growth increase) that best captured the growth increase associated with different...

Nonlinear stability of the 1D Boltzmann equation in a periodic box

NASA Astrophysics Data System (ADS)

Wu, Kung-Chien

2018-05-01

We study the nonlinear stability of the Boltzmann equation in the 1D periodic box with size , where is the Knudsen number. The convergence rate is for small time region and exponential for large time region. Moreover, the exponential rate depends on the size of the domain (Knudsen number). This problem is highly nonlinear and hence we need more careful analysis to control the nonlinear term.

Public Health and Law Collaboration: The Philadelphia Lead Court Study

PubMed Central

Gracely, Ed; Pan, Sarah; Cummings, Curtis; Palermo, Peter; Gould, George

2013-01-01

Objectives. We determined whether Philadelphia Lead Court is effective in enforcing lead hazard remediation in the homes of children with elevated blood lead levels. Methods. We created a deidentified data set for properties with an initial failed home inspection (IFHI) for lead hazards from January 1, 1998, through December 31, 2008, and compared compliance rates within the first year and time to compliance for lead hazard remediation between 1998 and 2002 (precourt period) and between 2003 and 2008 (court period). We evaluated predictors of time to compliance. Results. Within 1 year of the IFHI, 6.6% of the precourt and 76.8% of the court cases achieved compliance (P < .001) for the 3764 homes with data. Four years after the IFHI, 18% had attained compliance in the precourt period compared with 83.1% for the court period (P < .001). A proportional hazard analysis found that compliance was 8 times more likely in the court than the precourt period (P < .001). Conclusions. Lead court was more effective than precourt enforcement strategies. Most properties were remediated within 1 year of the IFHI, and time to compliance was significantly reduced. This model court could be replicated in other cities with similar enforcement problems. PMID:23678927

Enhanced diffusion with abnormal temperature dependence in underdamped space-periodic systems subject to time-periodic driving

NASA Astrophysics Data System (ADS)

Marchenko, I. G.; Marchenko, I. I.; Zhiglo, A. V.

2018-01-01

We present a study of the diffusion enhancement of underdamped Brownian particles in a one-dimensional symmetric space-periodic potential due to external symmetric time-periodic driving with zero mean. We show that the diffusivity can be enhanced by many orders of magnitude at an appropriate choice of the driving amplitude and frequency. The diffusivity demonstrates abnormal (decreasing) temperature dependence at the driving amplitudes exceeding a certain value. At any fixed driving frequency Ω normal temperature dependence of the diffusivity is restored at low enough temperatures, T

Exceptional points of resonant states on a periodic slab

NASA Astrophysics Data System (ADS)

Abdrabou, Amgad; Lu, Ya Yan

2018-06-01

A special kind of degeneracy, known as exceptional points (EPs), for resonant states on a dielectric periodic slab are investigated. Due to their unique properties, EPs have found important applications in lasing, sensing, unidirectional operations, etc. In general, EPs may appear in non-Hermitian eigenvalue problems, including those related to -parity-time-symmetric systems and those for open dielectric structures (due to the existence of radiation loss). In this paper, we study EPs on a simple periodic structure: a slab with a periodic array of gaps. By using an efficient numerical method, we calculate the EPs and study their dependence on geometric parameters. Analytic results are obtained for the limit as the periodic slab approaches a uniform one. Our work provides a simple platform for further studies concerning EPs on dielectric periodic structures, their unusual properties, and applications.

BMI and Lifetime Changes in BMI and Cancer Mortality Risk

PubMed Central

Taghizadeh, Niloofar; Boezen, H. Marike; Schouten, Jan P.; Schröder, Carolien P.; de Vries, E. G. Elisabeth; Vonk, Judith M.

2015-01-01

Body Mass Index (BMI) is known to be associated with cancer mortality, but little is known about the link between lifetime changes in BMI and cancer mortality in both males and females. We studied the association of BMI measurements (at baseline, highest and lowest BMI during the study-period) and lifetime changes in BMI (calculated over different time periods (i.e. short time period: annual change in BMI between successive surveys, long time period: annual change in BMI over the entire study period) with mortality from any cancer, and lung, colorectal, prostate and breast cancer in a large cohort study (n=8,645. Vlagtwedde-Vlaardingen, 1965-1990) with a follow-up on mortality status on December 31st 2008. We used multivariate Cox regression models with adjustments for age, smoking, sex, and place of residence. Being overweight at baseline was associated with a higher risk of prostate cancer mortality (hazard ratio (HR) =2.22; 95% CI 1.19-4.17). Obesity at baseline was associated with a higher risk of any cancer mortality [all subjects (1.23 (1.01-1.50)), and females (1.40 (1.07-1.84))]. Chronically obese females (females who were obese during the entire study-period) had a higher risk of mortality from any cancer (2.16 (1.47-3.18), lung (3.22 (1.06-9.76)), colorectal (4.32 (1.53-12.20)), and breast cancer (2.52 (1.15-5.54)). We found no significant association between long-term annual change in BMI and cancer mortality risk. Both short-term annual increase and decrease in BMI were associated with a lower mortality risk from any cancer [all subjects: (0.67 (0.47-0.94)) and (0.73 (0.55-0.97)), respectively]. In conclusion, a higher BMI is associated with a higher cancer mortality risk. This study is the first to show that short-term annual changes in BMI were associated with lower mortality from any type of cancer. PMID:25881129

Using Coupled Groundwater-Surface Water Models to Simulate Eco-Regional Differences in Climate Change Impacts on Hydrological Drought Regimes in British Columbia

NASA Astrophysics Data System (ADS)

Dierauer, J. R.; Allen, D. M.

2016-12-01

Climate change is expected to lead to an increase in extremes, including daily maximum temperatures, heat waves, and meteorological droughts, which will likely result in shifts in the hydrological drought regime (i.e. the frequency, timing, duration, and severity of drought events). While many studies have used hydrologic models to simulate climate change impacts on water resources, only a small portion of these studies have analyzed impacts on low flows and/or hydrological drought. This study is the first to use a fully coupled groundwater-surface water (gw-sw) model to study climate change impacts on hydrological drought. Generic catchment-scale gw-sw models were created for each of the six major eco-regions in British Columbia using the MIKE-SHE/MIKE-11 modelling code. Daily precipitation and temperature time series downscaled using bias-correction spatial disaggregation for the simulated period of 1950-2100 were obtained from the Pacific Climate Institute Consortium (PCIC). Streamflow and groundwater drought events were identified from the simulated time series for each catchment model using the moving window quantile threshold. The frequency, timing, duration, and severity of drought events were compared between the reference period (1961-2000) and two future time periods (2031-2060, 2071-2100). Results show how hydrological drought regimes across the different British Columbia eco-regions will be impacted by climate change.

Repeated measurements of mite and pet allergen levels in house dust over a time period of 8 years.

PubMed

Antens, C J M; Oldenwening, M; Wolse, A; Gehring, U; Smit, H A; Aalberse, R C; Kerkhof, M; Gerritsen, J; de Jongste, J C; Brunekreef, B

2006-12-01

Studies of the association between indoor allergen exposure and the development of allergic diseases have often measured allergen exposure at one point in time. We investigated the variability of house dust mite (Der p 1, Der f 1) and cat (Fel d 1) allergen in Dutch homes over a period of 8 years. Data were obtained in the Dutch PIAMA birth cohort study. Dust from the child's mattress, the parents' mattress and the living room floor was collected at four points in time, when the child was 3 months, 4, 6 and 8 years old. Dust samples were analysed for Der p 1, Der f 1 and Fel d 1 by sandwich enzyme immuno assay. Mite allergen concentrations for the child's mattress, the parents' mattress and the living room floor were moderately correlated between time-points. Agreement was better for cat allergen. For Der p 1 and Der f 1 on the child's mattress, the within-home variance was close to or smaller than the between-home variance in most cases. For Fel d 1, the within-home variance was almost always smaller than the between-home variance. Results were similar for allergen levels expressed per gram of dust and allergen levels expressed per square metre of the sampled surface. Variance ratios were smaller when samples were taken at shorter time intervals than at longer time intervals. Over a period of 4 years, mite and cat allergens measured in house dust are sufficiently stable to use single measurements with confidence in epidemiological studies. The within-home variance was larger when samples were taken 8 years apart so that over such long periods, repetition of sampling is recommended.

Studies of the Long Secondary Periods in Pulsating Red Giants. II. Lower-Luminosity Stars

NASA Astrophysics Data System (ADS)

Percy, J. R.; Leung, H. W.

2017-06-01

We have used AAVSO visual and photoelectric V data, and the AAVSO time-series package VSTAR and the Lomb-Scargle time-series algorithm to determine improved pulsation periods, "long secondary periods" (LSPs), and their amplitudes in 51 shorter-period pulsating red giants in the AAVSO photoelectric photometry program, and in the AAVSO long-period variable (LPV) binocular program. As is well known, radial pulsation becomes detectable in red giants at about spectral type M0, with periods of about 20 days. We find that the LSP phenomenon is also first detectable at about M0. Pulsation and LSP amplitudes increase from near zero to about 0.1 at pulsation periods of 100 days. At longer periods, the pulsation amplitudes continue to increase, but the LSP amplitudes are generally between 0.1 and 0.2 on average. The ratios of LSP to pulsation period cluster around 5 and 10, presumably depending on whether the pulsation period is the fundamental or first overtone. The pulsation and LSP phase curves are generally close to sinusoidal, except when the amplitude is small, in which case they may be distorted by observational scatter or, in the case of the LSP amplitude, by the pulsational variability. As with longer-period stars, the LSP amplitude i ncreases and decreases by a factor of two or more, for unknown reasons, on a time scale of about 20 LSPs. The LSP phenomenon is thus present and similar in radially pulsating red giants of all periods. Its cause remains unknown.

Direct solar-pumped iodine laser amplifier

NASA Technical Reports Server (NTRS)

Han, K. S.

1986-01-01

During this period the parametric studies of the iodine laser oscillator pumped by a Vortek simulator were carried out before amplifier studies. The amplifier studies are postponed to the extended period after completing the parametric studies. In addition, the kinetic modeling of a solar-pumped iodine laser amplifier, and the experimental work for a solar pumped dye laser amplifier are in progress. This report contains three parts: (1) a 10 W CW iodine laser pumped by a Vortek solar simulator; (2) kinetic modeling to predict the time to lasing threshold, lasing time, and energy output of solar-pumped iodine laser; and (3) the study of the dye laser amplifier pumped by a Tamarack solar simulator.

Relationship between Alcohol Purchasing Time and Alcohol Use Disorder in South Korea.

PubMed

Amista, Narcie Faith; Chun, Sungsoo; Yun, Mieun

2017-12-01

Currently, time of alcohol purchase is not part of the policies to regulate alcohol consumption in South Korea. This study was conducted to determine the relationship between alcohol purchasing time and alcohol use disorder. The survey for this study was conducted in geographically diverse regions of South Korea in 2012. Respondents' purchasing behaviors for both on-licensed (i.e., allows for consumption within the premises) and off-licensed (i.e., where alcohol is consumed off the premises) outlets and time of alcohol consumption were collected. Alcohol consumption patterns were examined using the Rapid Alcohol Problem Screen 4 (RAPS4). Data were also analyzed by age, gender and purchasing time. Results showed that among the off-licensed premises, supermarkets appear to be the most popular venue while for on-licensed premises; alcohol was generally consumed inside hotels/pubs regardless of age and gender of the purchaser. Purchasing of alcohol was highest during the day and early evening period (9:00 a.m. to 9:59 p.m.). Females are most likely to abuse alcohol than males during the early morning period and is that period after 12:00 midnight. Analysis suggests that the survey instrument used in the International Alcohol Control Study is being used to collect data on alcohol purchasing time consumption; therefore, the potential is there to provide accurate results to contribute appropriate policy responses to reduce alcohol related-harm.

Search for temporal changes in shear-wave splitting associated with the 2012 Te Maari Eruptions at Mount Tongariro, New Zealand

NASA Astrophysics Data System (ADS)

Godfrey, Holly J.; Shelley, Adrian; Savage, Martha K.

2014-10-01

We investigate changes in shear wave splitting and VP/VS ratios of local earthquakes from the GeoNet catalogue during a 16 month period beginning a year before the first Te Maari eruption at Mount Tongariro on August 6, 2012, focusing on four permanent seismographs located in proximity to the volcano. We identify four time periods bounded by sharp transitions that comprise the study period, during which moving averages of the shear-wave splitting parameters, Φ (fast direction) and δt (delay time), are fairly constant. At all stations, VP/VS is steady throughout most of the study period at 1.75. Small variations occur during the earthquake swarm at the volcano, which started a month before the first eruption, and for some low magnitude events occurring after a change in earthquake location method. Analysis of data sets in which epicentre location, hypocentre depth and event magnitude are restricted illustrates that observed temporal changes in shear-wave splitting parameters are likely due to the spatial variation of paths. This in turn is governed by the spatial distribution of seismicity and measurement quality. We think the short term variation in VP/VS ratios is due to event origin time uncertainty of low magnitude earthquakes or incorrect S-phase arrival timing for events in the Tongariro swarm. These results suggest that any volcanic processes able to cause changes in shear-wave splitting or VP/VS associated with the two eruptions during our study period were too localised to Te Maari to be observed at the seismographs studied using our methods. Dominant Φ observed during the study period are oriented approximately tangential to the Tongariro/Ngauruhoe massif at all four stations. We suggest that this may result from gravitational loading of Tongariro and Ngauruhoe mountains inducing fracturing or dilatation of tangentially oriented microcracks. There may also be some effect from layered material causing horizontal propagating rays yielding faster speed SH waves than SV at station NGZ. Measurements from shallow earthquakes in immediate proximity to the seismographs indicate the potential presence of a shallow, highly anisotropic body in the volcano.

Current fluctuations in periodically driven systems

NASA Astrophysics Data System (ADS)

Barato, Andre C.; Chetrite, Raphael

2018-05-01

Small nonequelibrium systems driven by an external periodic protocol can be described by Markov processes with time-periodic transition rates. In general, current fluctuations in such small systems are large and may play a crucial role. We develop a theoretical formalism to evaluate the rate of such large deviations in periodically driven systems. We show that the scaled cumulant generating function that characterizes current fluctuations is given by a maximal Floquet exponent. Comparing deterministic protocols with stochastic protocols, we show that, with respect to large deviations, systems driven by a stochastic protocol with an infinitely large number of jumps are equivalent to systems driven by deterministic protocols. Our results are illustrated with three case studies: a two-state model for a heat engine, a three-state model for a molecular pump, and a biased random walk with a time-periodic affinity.

Microfluidic oscillators with widely tunable periods

PubMed Central

Kim, Sung-Jin; Yokokawa, Ryuji; Takayama, Shuichi

2013-01-01

We present experiments and theory of a constant flow-driven microfluidic oscillator with widely tunable oscillation periods. This oscillator converts two constant input-flows from a syringe pump into an alternating, periodic output-flow with oscillation periods that can be adjusted to between 0.3 s to 4.1 h by tuning an external membrane capacitor. This capacitor allows multiple adjustable periods at a given input flow-rate, thus providing great flexibility in device operation. Also, we show that a sufficiently large external capacitance, relative to the internal capacitance of the microfluidic valve itself, is a critical requirement for oscillation. These widely tunable microfluidic oscillators are envisioned to be broadly useful for the study of biological rhythms, as on-chip timing sources for microfluidic logic circuits, and other applications that require variation in timed flow switching. PMID:23429765

Reducing EnergyPlus Run Time For Code Compliance Tools

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

Athalye, Rahul A.; Gowri, Krishnan; Schultz, Robert W.

2014-09-12

Integration of the EnergyPlus ™ simulation engine into performance-based code compliance software raises a concern about simulation run time, which impacts timely feedback of compliance results to the user. EnergyPlus annual simulations for proposed and code baseline building models, and mechanical equipment sizing result in simulation run times beyond acceptable limits. This paper presents a study that compares the results of a shortened simulation time period using 4 weeks of hourly weather data (one per quarter), to an annual simulation using full 52 weeks of hourly weather data. Three representative building types based on DOE Prototype Building Models and threemore » climate zones were used for determining the validity of using a shortened simulation run period. Further sensitivity analysis and run time comparisons were made to evaluate the robustness and run time savings of using this approach. The results of this analysis show that the shortened simulation run period provides compliance index calculations within 1% of those predicted using annual simulation results, and typically saves about 75% of simulation run time.« less

Early adolescence behavior problems and timing of poverty during childhood: A comparison of lifecourse models.

PubMed

Mazza, Julia Rachel S E; Lambert, Jean; Zunzunegui, Maria Victoria; Tremblay, Richard E; Boivin, Michel; Côté, Sylvana M

2017-03-01

Poverty is a well-established risk factor for the development of behavior problems, yet little is known about how timing of exposure to childhood poverty relates to behavior problems in early adolescence. To examine the differential effects of the timing of poverty between birth and late childhood on behavior problems in early adolescence by modeling lifecourse models, corresponding to sensitive periods, accumulation of risk and social mobility models. We used the Quebec Longitudinal Study of Child Development (N = 2120). Poverty was defined as living below the low-income thresholds defined by Statistics Canada and grouped into three time periods: between ages 0-3 years, 5-7 years, and 8-12 years. Main outcomes were teacher's report of hyperactivity, opposition and physical aggression at age 13 years. Structured linear regression analyses were conducted to estimate the contribution of poverty during the three selected time periods to behavior problems. Partial F-tests were used to compare nested lifecourse models to a full saturated model (all poverty main effects and possible interactions). Families who experienced poverty at all time periods were 9.3% of the original sample. Those who were poor at least one time period were 39.2%. The accumulation of risk model was the best fitting model for hyperactivity and opposition. The risk for physical aggression problems was associated only to poverty between 0 and 3 years supporting the sensitive period. Early and prolonged exposure to childhood poverty predicted higher levels of behavior problems in early adolescence. Antipoverty policies targeting the first years of life and long term support to pregnant women living in poverty are likely to reduce behavior problems in early adolescence. Copyright © 2017 Elsevier Ltd. All rights reserved.

[Retrospective cohort study on period of incubation and survival among former commercial plasma donors infected with HIV in Hebei province].

PubMed

Chen, Su-liang; Bai, Guang-yi; Li, Qiao-min; Li, Bao-jun; Hui, Yan-liang; Liang, Liang; Wang, Wei; Chen, Zhi-qiang; Lu, Xin-li; Wang, Xiao-feng; Zhang, Yu-qi; Zhao, Hong-ru

2012-04-01

To examine the state of incubation period and survival time of former commercial plasma donors (FCPDs) infected with HIV. All objects infected with HIV were from Hebei province and found from general investigation for FCPDs in 1995. The infector cohort by 142 cases was used to estimate incubation period. In the infector cohort, the time which infectors entered the cohort was their infection time, which was the middle value of the origin date, which was January 1, 1995. The onset of AIDS was defined as an outcome event. End point of observation was Dec 31, 2010. There were 192 months in all from beginning to end. The AIDS cohort by 57 cases was used to estimate the survival of the patients. In the patient cohort, the time of AIDS onset was defined as the time entering the cohort, and death of AIDS was defined as an outcome event. The cumulative incidence ratio, cumulative mortality, illness intensity and mortality intensity were analyzed through Kaplan-Meier. During the observation period, 123 cases of 142 infectors developed into AIDS, the cumulative incidence was 86.42% (123/142) and the intensity was 8.53/100 person-years and the median time of incubation period was 112.0 months (95%CI: 108.8 - 115.2). The death dates of 57 patients were from 1 to 24 months after onset. The cumulative mortality was 100%, and the intensity was 250.66/100 person-years and the median survival time was 3.0 months (95%CI: 1.8 - 4.2). It was estimated that the median time was 115.0 months (9.6 years) from infection to death. The median times of incubation and median survival time were 112.0 and 3.0 months, respectively.

Changes in Leisure-Time Physical Activity From the Prepregnancy to the Postpartum Period: 2004 Pelotas (Brazil) Birth Cohort Study.

PubMed

Coll, Carolina; Domingues, Marlos; Santos, Iná; Matijasevich, Alicia; Horta, Bernardo Lessa; Hallal, Pedro C

2016-04-01

The aim of this study was to evaluate changes in leisure-time physical activity (LTPA) and its correlates from prepregnancy to the postpartum period in mothers enrolled in a Brazilian birth cohort study. Our hypothesis was that LTPA would decline considerably during pregnancy. Maternal LTPA in the 3 months before pregnancy and during each trimester of pregnancy was assessed soon after delivery. A follow-up visit was conducted 3 months later. Weekly frequency and duration of each session of LTPA in a typical week were assessed for each period and a cut-off point of 150 minutes per week was used to classify women as active or not. The proportion of women active in leisure time declined from 11.3% in the prepregnancy to 2.3% in pregnancy and 0.1% in the postpartum period (P for trend <0.001). When considering any LTPA practice, the decline ranged from 15.4% to 4.4% and 7.5% (p for trend <0.001), respectively. Higher income, higher education and lower parity were the main predictors of LTPA practice. LTPA declined considerably during pregnancy and did not return to prepregnancy levels at 3 months postpartum. Mothers must be advised on the benefits of LTPA prepregnancy, during, and postpregnancy.

Long-Term Study of Heart Rate Variability Responses to Changes in the Solar and Geomagnetic Environment.

PubMed

Alabdulgader, Abdullah; McCraty, Rollin; Atkinson, Michael; Dobyns, York; Vainoras, Alfonsas; Ragulskis, Minvydas; Stolc, Viktor

2018-02-08

This long-term study examined relationships between solar and magnetic factors and the time course and lags of autonomic nervous system (ANS) responses to changes in solar and geomagnetic activity. Heart rate variability (HRV) was recorded for 72 consecutive hours each week over a five-month period in 16 participants in order to examine ANS responses during normal background environmental periods. HRV measures were correlated with solar and geomagnetic variables using multivariate linear regression analysis with Bonferroni corrections for multiple comparisons after removing circadian influences from both datasets. Overall, the study confirms that daily ANS activity responds to changes in geomagnetic and solar activity during periods of normal undisturbed activity and it is initiated at different times after the changes in the various environmental factors and persist over varying time periods. Increase in solar wind intensity was correlated with increases in heart rate, which we interpret as a biological stress response. Increase in cosmic rays, solar radio flux, and Schumann resonance power was all associated with increased HRV and parasympathetic activity. The findings support the hypothesis that energetic environmental phenomena affect psychophysical processes that can affect people in different ways depending on their sensitivity, health status and capacity for self-regulation.

Influencing preschoolers' free-play activity preferences: an evaluation of satiation and embedded reinforcement.

PubMed

Hanley, Gregory P; Tiger, Jeffrey H; Ingvarsson, Einar T; Cammilleri, Anthony P

2009-01-01

The present study evaluated the effects of classwide satiation and embedded reinforcement procedures on preschoolers' activity preferences during scheduled free-play periods. The goal of the study was to increase time allocation to originally nonpreferred, but important, activities (instructional zone, library, and science) while continuing to provide access to all free-play activities. The satiation intervention applied to preferred activities resulted in increased time allocation to the instructional and science activities, the customized embedded reinforcement interventions resulted in increased time allocation to all three target activities, and high levels of attendance to the instructional and library activities were maintained during follow-up observations. Implications for the design of preschool free-play periods are discussed.

Chaotic behaviour of the Rossler model and its analysis by using bifurcations of limit cycles and chaotic attractors

NASA Astrophysics Data System (ADS)

Ibrahim, K. M.; Jamal, R. K.; Ali, F. H.

2018-05-01

The behaviour of certain dynamical nonlinear systems are described in term as chaos, i.e., systems’ variables change with the time, displaying very sensitivity to initial conditions of chaotic dynamics. In this paper, we study archetype systems of ordinary differential equations in two-dimensional phase spaces of the Rössler model. A system displays continuous time chaos and is explained by three coupled nonlinear differential equations. We study its characteristics and determine the control parameters that lead to different behavior of the system output, periodic, quasi-periodic and chaos. The time series, attractor, Fast Fourier Transformation and bifurcation diagram for different values have been described.

CCD Photometric Observations and Light Curve Synthesis of the Near-Contact Binary XZ Canis Minoris

NASA Astrophysics Data System (ADS)

Kim, Chun-Hwey; Park, Jang-Ho; Lee, Jae Woo; Jeong, Jang-Hae

2009-06-01

Through the photometric observations of the near-contact binary, XZ CMi, new BV light curves were secured and seven times of minimum light were determined. An intensive period study with all published timings, including ours, confirms that the period of XZ CMi has varied in a cyclic period variation superposed on a secular period decrease over last 70 years. Assuming the cyclic change of period to occur by a light-time effect due to a third-body, the light-time orbit with a semi-amplitude of 0.0056d, a period of 29y and an eccentricity of 0.71 was calculated. The observed secular period decrease of -5.26× 10^{-11} d/P was interpreted as a result of simultaneous occurrence of both a period decrease of -8.20 × 10^{-11} d/P by angular momentum loss (AML) due to a magnetic braking stellar wind and a period increase of 2.94 × 10^{-11} d/P by a mass transfer from the less massive secondary to the primary components in the system. In this line the decreasi! ng rate of period due to AML is about 3 times larger than the increasing one by a mass transfer in their absolute values. The latter implies a mass transfer of dot M_{s}= 3.21 × 10^{-8} M_⊙ y^{-1} from the less massive secondary to the primary. The BV light curves with the latest Wilson-Devinney binary code were analyzed for two separate models of 8200K and 7000K as the photospheric temperature of the primary component. Both models confirm that XZ CMi is truly a near-contact binary with a less massive secondary completely filling Roche lobe and a primary inside the inner Roche lobe and there is a third-light corresponding to about 15-17% of the total system light. However, the third-light source can not be the same as the third-body suggested from the period study. At the present, however, we can not determine which one between two models is better fitted to the observations because of a negligible difference of sum (O-C)^2 between them. The diversity of mass ratios, with which previous investigators were in disagreement, still remains to be one of unsolved problems in XZ CMi system. Spectroscopic observations for a radial velocity curve and high-resolution spectra as well as a high-precision photometry are needed to resolve some of remaining problems.

Does Involuntary Mental Time Travel Make Sense in Prospective Teachers' Feelings and Behaviors during Lessons?

ERIC Educational Resources Information Center

Eren, Altay; Yesilbursa, Amanda

2013-01-01

This study examined the effects of involuntary mental time travel into the past and into the future on prospective teachers' feelings and behaviors during the period of a class hour. A total of 110 prospective teachers participated voluntarily in the study. The results of the present study showed that (a) the involuntary mental time travel into…

Oral Pseudoephedrine Decreases the Rate of Trans-mucosal Nitrous Oxide Exchange for the Middle Ear

PubMed Central

Teixeira, Miriam S.; Alper, Cuneyt M.; Martin, Brian S; Cullen Doyle, Brendan M.; Doyle, William J.

2015-01-01

Objective Determine if oral pretreatment with a vasoconstrictor decreases the blood to middle-ear exchange-rate of the perfusion-limited gas, Nitrous Oxide (N2O). Study Design Randomized, double-blind, crossover study. Methods Ten adult subjects with and 10 without past middle-ear disease completed paired experimental sessions, identical but for oral pretreatment with either pseudoephedrine HCL or lactose placebo. At each session, subjects were fitted with a non-rebreathing mask and breathed room air for 20 minutes (acclimation period), 50% N2O:50% O2 for 20 minutes (experimental period) and 100% O2 for 10 minutes (recovery period). Throughout, heart-rate, blood-pressure and O2 saturation were monitored and bilateral middle-ear pressures were recorded by tympanometry every minute. The primary outcome was the slope of the middle-ear pressure-time function for the experimental period which estimates the volume N2O exchange-rate. Using repeated measures ANOVA, the effects of Group (disease history), Treatment (active vs. placebo) and Period (1 vs. 2) on the recorded vital signs, and of Group, Treatment and Ear (left/right) on the middle-ear pressure-time slope were evaluated for statistical significance. Results Statistically significant effects of Period on O2 saturation (Period 2>Period 1) and of Treatment on heart-rate (Active>Placebo) were documented. Only Treatment was statistically significant for the middle-ear pressure-time slope with a shallower slope characterizing the active treatment session. Conclusion The volume exchange-rate across the middle-ear mucosa of perfusion-limited gases can be modulated pharmacologically. Theoretically, similar drugs can be used to reduce the requisite Eustachian tube opening efficiency for adequate middle-ear pressure regulation. PMID:26152838

29 CFR 552.102 - Live-in domestic service employees.

Code of Federal Regulations, 2010 CFR

2010-07-01

... themselves, the amount of sleeping time, meal time and other periods of complete freedom from all duties when... periods of free time (other than those relating to meals and sleeping) to be excluded from hours worked.... If the sleeping time, meal periods or other periods of free time are interrupted by a call to duty...

29 CFR 552.102 - Live-in domestic service employees.

Code of Federal Regulations, 2011 CFR

2011-07-01

... themselves, the amount of sleeping time, meal time and other periods of complete freedom from all duties when... periods of free time (other than those relating to meals and sleeping) to be excluded from hours worked.... If the sleeping time, meal periods or other periods of free time are interrupted by a call to duty...

The variability in Oxford hip and knee scores in the preoperative period: is there an ideal time to score?

PubMed

Quah, C; Holmes, D; Khan, T; Cockshott, S; Lewis, J; Stephen, A

2018-01-01

Background All NHS-funded providers are required to collect and report patient-reported outcome measures for hip and knee arthroplasty. Although there are established guidelines for timing such measures following arthroplasty, there are no specific time-points for collection in the preoperative period. The primary aim of this study was to identify whether there was a significant amount of variability in the Oxford hip and knee scores prior to surgical intervention when completed in the outpatient clinic at the time of listing for arthroplasty or when completed at the preoperative assessment clinic. Methods A prospective cohort study of patients listed for primary hip or knee arthroplasty was conducted. Patients were asked to fill in a preoperative Oxford score in the outpatient clinic at the time of listing. They were then invited to fill in the official outcome measures questionnaire at the preoperative assessment clinic. The postoperative Oxford score was then completed when the patient was seen again at their postoperative follow up in clinic. Results Of the total of 109 patients included in this study period, there were 18 (17%) who had a worse score of 4 or more points difference and 43 (39.4%) who had an improvement of 4 or more points difference when the scores were compared between time of listing at the outpatient and at the preoperative assessment clinic. There was a statistically significant difference (P = 0.0054) in the mean Oxford scores. Conclusions The results of our study suggest that there should be standardisation of timing for completing the preoperative patient-reported outcome measures.

Relationship Factors and Trajectories of Intimate Partner Violence among South African Women during Pregnancy and the Postpartum Period

PubMed Central

Groves, Allison K.; McNaughton-Reyes, H. Luz; Foshee, Vangie A.; Moodley, Dhayendre; Maman, Suzanne

2014-01-01

Intimate partner violence (IPV) is a significant public health problem in South Africa. However, there is limited research on whether and how IPV changes during pregnancy and the postpartum period and on the factors that might affect women's risk during this time. In this study, we describe the mean trajectories of physical and psychological IPV during pregnancy and the postpartum period and examine whether relationship power, partner social support, and relationship stress are associated with women's trajectories of IPV. Data come from a longitudinal study with 1,480 women recruited during pregnancy between May 2008 and June 2010 at a public clinic in Durban. Women completed behavioral assessments at their first antenatal visit, at fourteen weeks and at nine months postpartum. Women's experiences of IPV were measured at all three time points and relationship power, partner social support and relationship stress were each measured at the baseline assessment. We used multilevel random coefficients growth modeling to build our models. The mean trajectory for both types of IPV was flat which means that, on average, there was not significant change in levels of IPV over pregnancy and the postpartum period. However, there was significant individual variability in trajectories of IPV over the study period. Women who had higher relationship power had lower levels of physical and psychological IPV over time than women with lower relationship power. Additionally, women with higher relationship stress and lower partner support had higher levels of psychological IPV at pregnancy. Interventions that maximize women's relationship power and partner social support and minimize relationship stress during this transformative time are needed. PMID:25268363

Management and prognosis of locally recurrent rectal cancer - A national population-based study.

PubMed

Westberg, Karin; Palmer, Gabriella; Hjern, Fredrik; Johansson, Hemming; Holm, Torbjörn; Martling, Anna

2018-01-01

The rate of local recurrence of rectal cancer (LRRC) has decreased but the condition remains a therapeutic challenge. This study aimed to examine treatment and prognosis in patients with LRRC in Sweden. Special focus was directed towards potential differences between geographical regions and time periods. All patients with LRRC as first event, following primary surgery for rectal cancer performed during the period 1995-2002, were included in this national population-based cohort-study. Data were collected from the Swedish Colorectal Cancer Registry and from medical records. The cohort was divided into three time periods, based on the date of diagnosis of the LRRC. In total, 426 patients fulfilled the inclusion criteria. Treatment with curative intent was performed in 149 patients (35%), including 121 patients who had a surgical resection of the LRRC. R0-resection was achieved in 64 patients (53%). Patients with a non-centrally located tumour were more likely to have positive resection margins (R1/R2) (OR 5.02, 95% CI:2.25-11.21). Five-year survival for patients resected with curative intent was 43% after R0-resection and 14% after R1-resection. There were no significant differences in treatment intention or R0-resection rate between time periods or regions. The risk of any failure was significantly higher in R1-resected patients compared with R0-resected patients (HR 2.04, 95% CI:1.22-3.40). A complete resection of the LRRC is essential for potentially curative treatment. Time period and region had no influence on either margin status or prognosis. Copyright © 2017 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.

Social support and depression across the perinatal period: A longitudinal study.

PubMed

Li, Yang; Long, Zhouting; Cao, Danfeng; Cao, Fenglin

2017-09-01

To report changes in the prevalence of depression and the level of social support at three different time points in the perinatal period (late pregnancy, 1 week postpartum and 4 weeks postpartum) and to examine the relationship between depression and social support at these points in time. Social support is a modifiable factor for depression. Existing research is limited to examining social support at a single time point in relation to antepartum or postpartum depression. A longitudinal study. In total, 240 pregnant women were recruited from the prenatal clinic at a general hospital in China between June-September 2013. The Edinburgh Postnatal Depression Scale and Perceived Social Support Scale were used to measure the risk of depression and perceived social support at late pregnancy, within the first week postpartum, and at 4 weeks postpartum. The Perceived Social Support Scale scores within the first week after birth were higher than scores at the late pregnancy and postpartum week 4, while the Edinburgh Postnatal Depression Scale scores at late pregnancy were higher than scores at the two postpartum times. Women who had higher Perceived Social Support Scale scores at late pregnancy had less likelihood of developing antepartum depression, and women with higher Perceived Social Support Scale scores at postpartum week 4 were less likely to have postpartum depression. However, the Perceived Social Support Scale scores at late pregnancy did not predict the risk of postpartum depression. The study revealed that social support perceived by women changed over the perinatal period. Social support at each stage of the perinatal period was an important buffer against depression at this stage. An increased focus on the relationship between social support and depression at each stage of the perinatal period is necessary for future research and practice. © 2017 John Wiley & Sons Ltd.

OPTICAL STUDIES OF 13 HARD X-RAY SELECTED CATACLYSMIC BINARIES FROM THE SWIFT-BAT SURVEY

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

Halpern, Jules P.; Thorstensen, John R.

2015-12-15

From a set of 13 cataclysmic binaries that were discovered in the Swift Burst Alert Telescope (BAT) survey, we conducted time-resolved optical spectroscopy and/or time-series photometry of 11, with the goal of measuring their orbital periods and searching for spin periods. Seven of the objects in this study are new optical identifications. Orbital periods are found for seven targets, ranging from 81 minutes to 20.4 hr. PBC J0706.7+0327 is an AM Herculis star (polar) based on its emission-line variations and large amplitude photometric modulation on the same period. Swift J2341.0+7645 may be a polar, although the evidence here is lessmore » secure. Coherent pulsations are detected from two objects, Swift J0503.7−2819 (975 s) and Swift J0614.0+1709 (1412 s and 1530 s, spin and beat periods, respectively), indicating that they are probable intermediate polars (DQ Herculis stars). For two other stars, longer spin periods are tentatively suggested. We also present the discovery of a 2.00 hr X-ray modulation from RX J2015.6+3711, possibly a contributor to Swift J2015.9+3715, and likely a polar.« less

Identification of five time periods on the Indonesian stock exchange index historical data since 1997 to 2016

NASA Astrophysics Data System (ADS)

Riveli, N.; Suroto, B. J.

2018-05-01

We are investigating the behavioural changes of the Indonesian financial systems in the last 20 years. Changes in the financial system behaviour were indicated by differences in the statistical properties of the daily log return distribution in two adjacent time windows. To measure how likely two distributions are differ, the Kolmogorov-Smirnov (KS) Test was applied. We have found that we can divide our time series data into five segments, where the KS probability values between two adjacent segments are maximum. This finding can be used to study the effect on the financial system imposed by, for example, the socio-economy and political policy by the government, by studying the changes in such factors in the identified time periods.

Sensitivity Study for Long Term Reliability

NASA Technical Reports Server (NTRS)

White, Allan L.

2008-01-01

This paper illustrates using Markov models to establish system and maintenance requirements for small electronic controllers where the goal is a high probability of continuous service for a long period of time. The system and maintenance items considered are quality of components, various degrees of simple redundancy, redundancy with reconfiguration, diagnostic levels, periodic maintenance, and preventive maintenance. Markov models permit a quantitative investigation with comparison and contrast. An element of special interest is the use of conditional probability to study the combination of imperfect diagnostics and periodic maintenance.

"I'll be your cigarette--light me up and get on with it": examining smoking imagery on YouTube.

PubMed

Forsyth, Susan R; Malone, Ruth E

2010-08-01

Smoking imagery on the online video sharing site YouTube is prolific and easily accessed. However, no studies have examined how this content changes across time. We studied the primary message and genre of YouTube videos about smoking across two time periods. In May and July 2009, we used "cigarettes" and "smoking cigarettes" to retrieve the top 20 videos on YouTube by relevance and view count. Eliminating duplicates, 124 videos were coded for time period, overall message, genre, and brand mentions. Data were analyzed using descriptive statistics. Videos portraying smoking positively far outnumbered smoking-negative videos in both samples, increasing as a percentage of total views across the time period. Fifty-eight percent of videos in the second sample were new. Among smoking-positive videos, music and magic tricks were most numerous, increasing from 66% to nearly 80% in July, with music accounting for most of the increase. Marlboro was the most frequently mentioned brand. Videos portraying smoking positively predominate on YouTube, and this pattern persists across time. Tobacco control advocates could use YouTube more effectively to counterbalance prosmoking messages.

“I'll be your cigarette—Light me up and get on with it”: Examining smoking imagery on YouTube

PubMed Central

Forsyth, Susan R.

2010-01-01

Introduction: Smoking imagery on the online video sharing site YouTube is prolific and easily accessed. However, no studies have examined how this content changes across time. We studied the primary message and genre of YouTube videos about smoking across two time periods. Methods: In May and July 2009, we used “cigarettes” and “smoking cigarettes” to retrieve the top 20 videos on YouTube by relevance and view count. Eliminating duplicates, 124 videos were coded for time period, overall message, genre, and brand mentions. Data were analyzed using descriptive statistics. Results: Videos portraying smoking positively far outnumbered smoking-negative videos in both samples, increasing as a percentage of total views across the time period. Fifty-eight percent of videos in the second sample were new. Among smoking-positive videos, music and magic tricks were most numerous, increasing from 66% to nearly 80% in July, with music accounting for most of the increase. Marlboro was the most frequently mentioned brand. Discussion: Videos portraying smoking positively predominate on YouTube, and this pattern persists across time. Tobacco control advocates could use YouTube more effectively to counterbalance prosmoking messages. PMID:20634267

Meniscal Extrusion Progresses Shortly after the Medial Meniscus Posterior Root Tear.

PubMed

Furumatsu, Takayuki; Kodama, Yuya; Kamatsuki, Yusuke; Hino, Tomohito; Okazaki, Yoshiki; Ozaki, Toshifumi

2017-12-01

Medial meniscus posterior root tears (MMPRT) induce medial meniscus extrusion (MME). However, the time-dependent extent of MME in patients suffering from the MMPRT remains unclear. This study evaluated the extent of MME after painful popping events that occurred at the onset of the MMPRT. Thirty-five patients who had an episode of posteromedial painful popping were investigated. All the patients were diagnosed as having an MMPRT by magnetic resonance imaging (MRI) within 12 months after painful popping. Medial meniscus body width (MMBW), absolute MME, and relative MME (100×absolute MME/MMBW) were assessed among three groups divided according to the time after painful popping events: early period (〈1 month), subacute period (1-3 months), and chronic period (4-12 months). In the early period, absolute and relative MMEs were 3.0 mm and 32.7%, respectively. Absolute MME increased up to 4.2 mm and 5.8 mm during the subacute and chronic periods, respectively. Relative MME also progressed to 49.2% and 60.3% in the subacute and chronic periods, respectively. This study demonstrated that absolute and relative MMEs increased progressively within the short period after the onset of symptomatic MMPRT. Our results suggest that early diagnosis of an MMPRT may be important to prevent progression of MME following the MMPRT.

Earlier Is Better: Learning English in Saudi Arabia

ERIC Educational Resources Information Center

Alsairi, Meshari A.

2018-01-01

Various studies have been carried out in order to find out the suitable age for foreign language acquisition. Every research study has had a different Critical Period (CP) and most of them have not been really close together in terms of years. Critical Period refers to the actual time frame during which foreign language acquisition should take…

A Longitudinal Study of Narrative Development in Children and Adolescents with Down Syndrome

ERIC Educational Resources Information Center

Cleave, Patricia; Bird, Elizabeth Kay-Raining; Czutrin, Rachael; Smith, Lindsey

2012-01-01

The present study examined narrative development in children and adolescents with Down syndrome longitudinally. Narratives were collected from 32 children and adolescents with Down syndrome three times over a 1-year period. Both micro- and macrolevel analyses were conducted. Significant growth over the 1-year period was seen in semantic complexity…

University Leadership during Times of Significant Transformation: A Case of Kyambogo University in Uganda

ERIC Educational Resources Information Center

Namubiru, Gertrude; Onen, David; Oonyu, Joseph

2017-01-01

This study investigated how leadership was exercised at Kyambogo University [KyU] (in Uganda) during its formation that involved the merger of three tertiary institutions and the period immediately thereafter. This was regarded as a period of significant transformation at the institution. The study was prompted by the rampant strikes and protests…

Time trend tendency (1988-2014 years) of organochlorine pesticide levels in the adipose tissue of Veracruz inhabitants.

PubMed

Calderón-Garcidueñas, Ana Laura; Waliszewski, Stefan M; Ruiz-Ramos, Rubén; Del Carmen Martinez-Valenzuela, María

2018-03-10

The population that lives in areas where organochlorine pesticides were spread in the past is still exposed to them through contaminated food, particulate matter, and vapors. Due to their lipophilic properties and resistance to metabolic reactions, they accumulate in tissues and fluids rich in lipids. The aim of the study was to monitor the concentrations of organochlorine pesticides in forensic adipose tissue samples of adult inhabitants of Veracruz City, Mexico, and compare their time trend levels from 1988 to 2014. During the study, hexachlorobenzene (HCB); lindane; β-hexachorocyclohexane; p,p'-dichlorodiphenyldichloroethylene (pp'DDE); p,p'-dichlorodiphenyldichloroethane (p,p'-DDT); and o,p'-dichlorodiphenyldichloroethane (o,p'-DDT) were determined. Our survey was divided into two periods: first, from the years 1988 to 1999, during which DDT was allowed to fight malaria and dengue vectors and the second from the years 2001 to 2014, after the DDT ban. A total of 1435 samples were analyzed. There were substantial differences in the forecasted time trend values of p,p'-DDE and p,p'-DDT in human adipose tissue samples in the two different periods. During the first period, p,p'-DDE decrease time trend was 1.198 mg/kg on lipid base per year; for the second one, decrease was 0.128 mg/kg on lipid base per year. p,p'-DDT decreased 0.507 mg/kg on lipid base during the first period and 0.039 mg/kg on lipid base for the second. The different concentrations may be explained by the cessation of fresh exposure after the first period and a more equilibrated decontamination tendency during the second period. This model was useful to show the decrease in the concentration of pesticides in human adipose tissue samples.

Discovering Periodic Patterns in Historical News

PubMed Central

Dzogang, Fabon; Lansdall-Welfare, Thomas; Cristianini, Nello

2016-01-01

We address the problem of observing periodic changes in the behaviour of a large population, by analysing the daily contents of newspapers published in the United States and United Kingdom from 1836 to 1922. This is done by analysing the daily time series of the relative frequency of the 25K most frequent words for each country, resulting in the study of 50K time series for 31,755 days. Behaviours that are found to be strongly periodic include seasonal activities, such as hunting and harvesting. A strong connection with natural cycles is found, with a pronounced presence of fruits, vegetables, flowers and game. Periodicities dictated by religious or civil calendars are also detected and show a different wave-form than those provoked by weather. States that can be revealed include the presence of infectious disease, with clear annual peaks for fever, pneumonia and diarrhoea. Overall, 2% of the words are found to be strongly periodic, and the period most frequently found is 365 days. Comparisons between UK and US, and between modern and historical news, reveal how the fundamental cycles of life are shaped by the seasons, but also how this effect has been reduced in modern times. PMID:27824911

Daily Light Exposure Patterns Reveal Phase and Period of the Human Circadian Clock.

PubMed

Woelders, Tom; Beersma, Domien G M; Gordijn, Marijke C M; Hut, Roelof A; Wams, Emma J

2017-06-01

Light is the most potent time cue that synchronizes (entrains) the circadian pacemaker to the 24-h solar cycle. This entrainment process is an interplay between an individual's daily light perception and intrinsic pacemaker period under free-running conditions. Establishing individual estimates of circadian phase and period can be time-consuming. We show that circadian phase can be accurately predicted (SD = 1.1 h for dim light melatonin onset, DLMO) using 9 days of ambulatory light and activity data as an input to Kronauer's limit-cycle model for the human circadian system. This approach also yields an estimated circadian period of 24.2 h (SD = 0.2 h), with longer periods resulting in later DLMOs. A larger amount of daylight exposure resulted in an earlier DLMO. Individuals with a long circadian period also showed shorter intervals between DLMO and sleep timing. When a field-based estimation of tau can be validated under laboratory studies in a wide variety of individuals, the proposed methods may prove to be essential tools for individualized chronotherapy and light treatment for shift work and jetlag applications. These methods may improve our understanding of fundamental properties of human circadian rhythms under daily living conditions.

Daily Light Exposure Patterns Reveal Phase and Period of the Human Circadian Clock

PubMed Central

Woelders, Tom; Beersma, Domien G. M.; Gordijn, Marijke C. M.; Hut, Roelof A.; Wams, Emma J.

2017-01-01

Light is the most potent time cue that synchronizes (entrains) the circadian pacemaker to the 24-h solar cycle. This entrainment process is an interplay between an individual’s daily light perception and intrinsic pacemaker period under free-running conditions. Establishing individual estimates of circadian phase and period can be time-consuming. We show that circadian phase can be accurately predicted (SD = 1.1 h for dim light melatonin onset, DLMO) using 9 days of ambulatory light and activity data as an input to Kronauer’s limit-cycle model for the human circadian system. This approach also yields an estimated circadian period of 24.2 h (SD = 0.2 h), with longer periods resulting in later DLMOs. A larger amount of daylight exposure resulted in an earlier DLMO. Individuals with a long circadian period also showed shorter intervals between DLMO and sleep timing. When a field-based estimation of tau can be validated under laboratory studies in a wide variety of individuals, the proposed methods may prove to be essential tools for individualized chronotherapy and light treatment for shift work and jetlag applications. These methods may improve our understanding of fundamental properties of human circadian rhythms under daily living conditions. PMID:28452285

Changing Land Use: Peachtree Street, Atlanta. A Case Study in Sequent Occupance [And] Student Work Book.

ERIC Educational Resources Information Center

Laws, Kevin

A social studies unit and student workbook explore the historical geography of the area of Peachtree Street in Atlanta, Georgia. The unit deals with sequent occupance, a type of historical geography in which students study the same area, the changes in culture, and the changing land use in the area during certain time periods. For each period,…

The Physical Nature and Orbital Behavior of the Eclipsing System DK Cygni

NASA Astrophysics Data System (ADS)

Lee, Jae Woo; Youn, Jae-Hyuck; Park, Jang-Ho; Wolf, Marek

2015-06-01

New CCD photometry is presented for the hot overcontact binary DK Cyg together with reasonable explanations for the light and period variations. Historical light and velocity curves from 1962 to 2012 were simultaneously analyzed with the Wilson-Devinney (W-D) synthesis code. The brightness disturbances were satisfactorily modeled by applying a magnetic cool spot on the primary star. Based on 261 times of minimum light that include 116 new timings and span more than 87 years, a period study reveals that the orbital period has varied due to a periodic oscillation superimposed on an upward parabola. The period and semi-amplitude of the modulation are about 78.1 years and 0.0037 days, respectively. This detail is interpreted as a light-travel-time effect due to a circumbinary companion with a minimum mass of M3 = 0.065 M⊙, within the theoretical limit of ˜0.07 M⊙ for a brown dwarf star. The observed period increase at a fractional rate of +2.74 × 10-10 is in excellent agreement with that calculated from our W-D synthesis. Mass transfer from the secondary to the primary component is mainly responsible for the secular period change. We examined the evolutionary status of the DK Cyg system from the absolute dimensions.

7 CFR 1.603 - How are time periods computed?

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 1 2010-01-01 2010-01-01 false How are time periods computed? 1.603 Section 1.603 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Conditions in FERC Hydropower Licenses General Provisions § 1.603 How are time periods computed? (a) General. Time periods are computed...

Laparoscopic Splenectomy with Technical Standardization and Selection Criteria for Standard or Hand-Assisted Approach in 390 Patients with Liver Cirrhosis and Portal Hypertension.

PubMed

Kawanaka, Hirofumi; Akahoshi, Tomohiko; Kinjo, Nao; Harimoto, Norifumi; Itoh, Shinji; Tsutsumi, Norifumi; Matsumoto, Yoshihiro; Yoshizumi, Tomoharu; Shirabe, Ken; Maehara, Yoshihiko

2015-08-01

Laparoscopic splenectomy (LS) is still challenging in patients with liver cirrhosis and portal hypertension. This study was designed to establish safe and less invasive LS in patients with liver cirrhosis and portal hypertension. We analyzed 390 patients with liver cirrhosis and portal hypertension, who underwent LS between 1993 and 2013. Patients were divided into 3 time periods; early (1993 to 2004, n = 106); middle (2005 to 2008, n = 159); and late (2008 to 2013, n = 125). During the middle time period, standardized technique for LS and selection criteria for hand-assisted LS were adopted. Patients with spleen volume ≥ 1,000 mL by CT volumetry, large perisplenic collateral vessels, and/or Child-Pugh score ≥ 9, underwent hand-assisted LS. During the late time period, the selection criteria were refined and patients with spleen volume ≥ 600 mL underwent hand-assisted LS. Conversion to open splenectomy decreased (10.4% in the early time period, 1.9% in the middle time period, and 3.2% in the late time period, p = 0.004), median blood loss decreased (300g, 87g, and 98g, respectively, p < 0.001), and the success rate of pure LS tended to improve (87.2%, 89.5%, and 98.0%, respectively, p = 0.110). Mortality was 0% in each time period, Clavien-Dindo grade IIIb or more complications tended to decrease (5.7%, 2.5%, and 0.8%, respectively, p = 0.081), and technique-related complications decreased significantly (10.4%, 3.8%, and 2.4%, respectively, p = 0.014). Laparoscopic splenectomy is now a safe and less invasive approach, even in patients with liver cirrhosis and portal hypertension, because of its technical standardization with the refined selection criteria for pure or hand-assisted LS. Copyright © 2015 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

Prior video game utilization is associated with improved performance on a robotic skills simulator.

PubMed

Harbin, Andrew C; Nadhan, Kumar S; Mooney, James H; Yu, Daohai; Kaplan, Joshua; McGinley-Hence, Nora; Kim, Andrew; Gu, Yiming; Eun, Daniel D

2017-09-01

Laparoscopic surgery and robotic surgery, two forms of minimally invasive surgery (MIS), have recently experienced a large increase in utilization. Prior studies have shown that video game experience (VGE) may be associated with improved laparoscopic surgery skills; however, similar data supporting a link between VGE and proficiency on a robotic skills simulator (RSS) are lacking. The objective of our study is to determine whether volume or timing of VGE had any impact on RSS performance. Pre-clinical medical students completed a comprehensive questionnaire detailing previous VGE across several time periods. Seventy-five subjects were ultimately evaluated in 11 training exercises on the daVinci Si Skills Simulator. RSS skill was measured by overall score, time to completion, economy of motion, average instrument collision, and improvement in Ring Walk 3 score. Using the nonparametric tests and linear regression, these metrics were analyzed for systematic differences between non-users, light, and heavy video game users based on their volume of use in each of the following four time periods: past 3 months, past year, past 3 years, and high school. Univariate analyses revealed significant differences between heavy and non-users in all five performance metrics. These trends disappeared as the period of VGE went further back. Our study showed a positive association between video game experience and robotic skills simulator performance that is stronger for more recent periods of video game use. The findings may have important implications for the evolution of robotic surgery training.

Analysis of stability and bifurcations of fixed points and periodic solutions of a lumped model of neocortex with two delays

PubMed Central

2012-01-01

A lumped model of neural activity in neocortex is studied to identify regions of multi-stability of both steady states and periodic solutions. Presence of both steady states and periodic solutions is considered to correspond with epileptogenesis. The model, which consists of two delay differential equations with two fixed time lags is mainly studied for its dependency on varying connection strength between populations. Equilibria are identified, and using linear stability analysis, all transitions are determined under which both trivial and non-trivial fixed points lose stability. Periodic solutions arising at some of these bifurcations are numerically studied with a two-parameter bifurcation analysis. PMID:22655859

Disentangling the effects of low self-esteem and stressful events on depression: findings from three longitudinal studies.

PubMed

Orth, Ulrich; Robins, Richard W; Meier, Laurenz L

2009-08-01

Diathesis-stress models of depression suggest that low self-esteem and stressful events jointly influence the development of depressive affect. More specifically, the self-esteem buffering hypothesis states that, in the face of challenging life circumstances, individuals with low self-esteem are prone to depression because they lack sufficient coping resources, whereas those with high self-esteem are able to cope effectively and consequently avoid spiraling downward into depression. The authors used data from 3 longitudinal studies of adolescents and young adults, who were assessed 4 times over a 3-year period (Study 1; N = 359), 3 times over a 6-week period (Study 2; N = 249), and 4 times over a 6-year period (Study 3; N = 2,403). In all 3 studies, low self-esteem and stressful events independently predicted subsequent depression but did not interact in the prediction. Thus, the results did not support the self-esteem buffering hypothesis but suggest that low self-esteem and stressful events operate as independent risk factors for depression. In addition, the authors found evidence in all 3 studies that depression, but not low self-esteem, is reciprocally related to stressful events, suggesting that individuals high in depression are more inclined to subsequently experience stressful events.

A Novel Analysis Of The Connection Between Indian Monsoon Rainfall And Solar Activity

NASA Astrophysics Data System (ADS)

Bhattacharyya, S.; Narasimha, R.

2005-12-01

The existence of possible correlations between the solar cycle period as extracted from the yearly means of sunspot numbers and any periodicities that may be present in the Indian monsoon rainfall has been addressed using wavelet analysis. The wavelet transform coefficient maps of sunspot-number time series and those of the homogeneous Indian monsoon rainfall annual time series data reveal striking similarities, especially around the 11-year period. A novel method to analyse and quantify this similarity devising statistical schemes is suggested in this paper. The wavelet transform coefficient maxima at the 11-year period for the sunspot numbers and the monsoon rainfall have each been modelled as a point process in time and a statistical scheme for identifying a trend or dependence between the two processes has been devised. A regression analysis of parameters in these processes reveals a nearly linear trend with small but systematic deviations from the regressed line. Suitable function models for these deviations have been obtained through an unconstrained error minimisation scheme. These models provide an excellent fit to the time series of the given wavelet transform coefficient maxima obtained from actual data. Statistical significance tests on these deviations suggest with 99% confidence that the deviations are sample fluctuations obtained from normal distributions. In fact our earlier studies (see, Bhattacharyya and Narasimha, 2005, Geophys. Res. Lett., Vol. 32, No. 5) revealed that average rainfall is higher during periods of greater solar activity for all cases, at confidence levels varying from 75% to 99%, being 95% or greater in 3 out of 7 of them. Analysis using standard wavelet techniques reveals higher power in the 8--16 y band during the higher solar activity period, in 6 of the 7 rainfall time series, at confidence levels exceeding 99.99%. Furthermore, a comparison between the wavelet cross spectra of solar activity with rainfall and noise (including those simulating the rainfall spectrum and probability distribution) revealed that over the two test-periods respectively of high and low solar activity, the average cross power of the solar activity index with rainfall exceeds that with the noise at z-test confidence levels exceeding 99.99% over period-bands covering the 11.6 y sunspot cycle (see, Bhattacharyya and Narasimha, SORCE 2005 14-16th September, at Durango, Colorado USA). These results provide strong evidence for connections between Indian rainfall and solar activity. The present study reveals in addition the presence of subharmonics of the solar cycle period in the monsoon rainfall time series together with information on their phase relationships.

A life course perspective on how racism may be related to health inequities.

PubMed

Gee, Gilbert C; Walsemann, Katrina M; Brondolo, Elizabeth

2012-05-01

Recent studies show that racism may influence health inequities. As individuals grow from infancy into old age, they encounter social institutions that may create new exposures to racial bias. Yet, few studies have considered this idea fully. We suggest a framework that shows how racism and health inequities may be viewed from a life course perspective. It applies the ideas of age-patterned exposures, sensitive periods, linked lives, latency period, stress proliferation, historic period, and cohorts. It suggests an overarching idea that racism can structure one's time in asset-building contexts (e.g., education) or disadvantaged contexts (e.g., prison). This variation in time and exposure can contribute to racial inequities in life expectancy and other health outcomes across the life course and over generations.

A Life Course Perspective on How Racism May Be Related to Health Inequities

PubMed Central

Walsemann, Katrina M.; Brondolo, Elizabeth

2012-01-01

Recent studies show that racism may influence health inequities. As individuals grow from infancy into old age, they encounter social institutions that may create new exposures to racial bias. Yet, few studies have considered this idea fully. We suggest a framework that shows how racism and health inequities may be viewed from a life course perspective. It applies the ideas of age-patterned exposures, sensitive periods, linked lives, latency period, stress proliferation, historic period, and cohorts. It suggests an overarching idea that racism can structure one’s time in asset-building contexts (e.g., education) or disadvantaged contexts (e.g., prison). This variation in time and exposure can contribute to racial inequities in life expectancy and other health outcomes across the life course and over generations. PMID:22420802

The time of the insult/triggering event in Legg-Calvé-Perthes' disease determined by incubation period modeling and the age distribution of children with Perthes'.

PubMed

Loder, Randall T; Browne, Richard H; Millis, Andrew; Kim, Wook-Cheol; Shah, Hitesh; Cosgrove, Aidan P; Wiig, Ola

2012-01-01

The time when the insult/triggering event occurs in Legg-Calvé-Perthes' (LCPD) is unknown. the purpose of this study was to determine, using the mathematical tool of incubation period modeling, the time of such event and the incubation period for LCPD. We reviewed 2,911 children with LCPD from 10 different centers around the world. They were divided into two groups: those from India (505 children, mean age 8.1 ± 2.3 years) and those from other than India (2,406 children, mean age 5.8 ± 2.2 years). A simple distribution with an excellent fit to the data was ln(y) = a + bx + cxln(x), where y is the proportion of children with LCPD at age of diagnosis x (r(2) = 0.994 for non-Indian and 0.959 for Indian children). The age of the triggering event was 1.32 years for non-Indian and 2.77 years for Indian children; the median incubation period was 4.30 years non-Indian and 5.33 years for Indian patients. Knowing the incubation period and age of triggering event narrows the number of potential etiologies in LCPD. this study does not support a prenatal triggering event as postulated in the past. similar incubation periods with different ages at diagnosis supports a common insult which occurs at different ages in different populations dependent upon local factors such as geographic location and ethnicity.

Causality and correlations between BSE and NYSE indexes: A Janus faced relationship

NASA Astrophysics Data System (ADS)

Neeraj; Panigrahi, Prasanta K.

2017-09-01

We study the multi-scale temporal correlations and causality connections between the New York Stock Exchange (NYSE) and Bombay Stock Exchange (BSE) monthly average closing price indexes for a period of 300 months, encompassing the time period of the liberalisation of the Indian economy and its gradual global exposure. In multi-scale analysis; clearly identifiable 1, 2 and 3 year non-stationary periodic modulations in NYSE and BSE have been observed, with NYSE commensurating changes in BSE at 3 years scale. Interestingly, at one year time scale, the two exchanges are phase locked only during the turbulent times, while at the scale of three year, in-phase nature is observed for a much longer time frame. The two year time period, having characteristics of both one and three year variations, acts as the transition regime. The normalised NYSE's stock value is found to Granger cause those of BSE, with a time lag of 9 months. Surprisingly, observed Granger causality of high frequency variations reveals BSE behaviour getting reflected in the NYSE index fluctuations, after a smaller time lag. This Janus faced relationship, shows that smaller stock exchanges may provide a natural setting for simulating market fluctuations of much bigger exchanges. This possibly arises due to the fact that high frequency fluctuations form an universal part of the financial time series, and are expected to exhibit similar characteristics in open market economies.

12 CFR 516.10 - How does OTS compute time periods under this part?

Code of Federal Regulations, 2010 CFR

2010-01-01

... APPLICATION PROCESSING PROCEDURES § 516.10 How does OTS compute time periods under this part? In computing time periods under this part, OTS does not include the day of the act or event that commences the time... 12 Banks and Banking 5 2010-01-01 2010-01-01 false How does OTS compute time periods under this...

Cost study : before, during and after AOS implementation (October 1996 - May 1999)

DOT National Transportation Integrated Search

This study compared AATA operating costs over two different time periods: before and during AOS installation. While neither additional operating costs nor operating costs savings were traceable to AOS at this time, the implications of this report, wh...

Interaction between Education and Household Wealth on the Risk of Obesity in Women in Egypt

PubMed Central

Aitsi-Selmi, Amina; Chandola, Tarani; Friel, Sharon; Nouraei, Reza; Shipley, Martin J.; Marmot, Michael G.

2012-01-01

Background Obesity is a growing problem in lower income countries particularly among women. There are few studies exploring individual socioeconomic status indicators in depth. This study examines the interaction of education and wealth in relation to obesity, hypothesising that education protects against the obesogenic effect of wealth. Methods Four datasets of women of reproductive age from the Egyptian Demographic and Health Surveys spanning the period 1992–2008 are used to examine two distinct time periods: 1992/95 (N = 11097) and 2005/08 (N = 23178). The association in the two time periods between education level and household wealth in relation to the odds of being obese is examined, and the interaction between the two socioeconomic indicators investigated. Estimates are adjusted for age group and area of residence. Results An interaction was found between the association of education and wealth with obesity in both time periods (P-value for interaction <0.001). For women with the lowest education level, moving up one wealth quintile was associated with a 78% increase in the odds of obesity in 1992/95 (OR; 95%CI: 1.78; 1.65,1.91) and a 33% increase in 2005/08 (OR; 95%CI: 1.33; 1.26,1.39). For women with the highest level of education, there was little evidence of an association between wealth and obesity (OR; 95%CI: 0.82; 0.57,1.16 in 1992/95 and 0.95; 0.84,1.08 in 2005/08). Obesity levels increased most in women who were in the no/primary education, poorest wealth quintile and rural groups (absolute difference in prevalence percentage points between the two time periods: 20.2, 20.1, and 21.3 respectively). Conclusion In the present study, wealth appears to be a risk factor for obesity in women with lower education levels, while women with higher education are protected. The findings also suggest that a reversal in the social distribution of obesity risk is occurring which can be explained by the large increase in obesity levels in lower socioeconomic groups between the two time periods. PMID:22761807

Interaction between education and household wealth on the risk of obesity in women in Egypt.

PubMed

Aitsi-Selmi, Amina; Chandola, Tarani; Friel, Sharon; Nouraei, Reza; Shipley, Martin J; Marmot, Michael G

2012-01-01

Obesity is a growing problem in lower income countries particularly among women. There are few studies exploring individual socioeconomic status indicators in depth. This study examines the interaction of education and wealth in relation to obesity, hypothesising that education protects against the obesogenic effect of wealth. Four datasets of women of reproductive age from the Egyptian Demographic and Health Surveys spanning the period 1992-2008 are used to examine two distinct time periods: 1992/95 (N = 11097) and 2005/08 (N = 23178). The association in the two time periods between education level and household wealth in relation to the odds of being obese is examined, and the interaction between the two socioeconomic indicators investigated. Estimates are adjusted for age group and area of residence. An interaction was found between the association of education and wealth with obesity in both time periods (P-value for interaction <0.001). For women with the lowest education level, moving up one wealth quintile was associated with a 78% increase in the odds of obesity in 1992/95 (OR; 95%CI: 1.78; 1.65,1.91) and a 33% increase in 2005/08 (OR; 95%CI: 1.33; 1.26,1.39). For women with the highest level of education, there was little evidence of an association between wealth and obesity (OR; 95%CI: 0.82; 0.57,1.16 in 1992/95 and 0.95; 0.84,1.08 in 2005/08). Obesity levels increased most in women who were in the no/primary education, poorest wealth quintile and rural groups (absolute difference in prevalence percentage points between the two time periods: 20.2, 20.1, and 21.3 respectively). In the present study, wealth appears to be a risk factor for obesity in women with lower education levels, while women with higher education are protected. The findings also suggest that a reversal in the social distribution of obesity risk is occurring which can be explained by the large increase in obesity levels in lower socioeconomic groups between the two time periods.

Comparison of the financial performance of Islamic and conventional bank in Malaysia during and after economic crisis

NASA Astrophysics Data System (ADS)

Kadir, Norhidayah A.; Jaffar, Aidatullaini; Abdullah, Nur Lina; Harun, Nurzalina

2013-09-01

This paper is a continuation of our former work. In this paper, we compare the financial performance of the two banking systems that exist in Malaysia over two periods of time, during economic crisis (1997-1999) and after economic crisis (2001-2003). In order to see the conventional as well as Islamic bank's performance over these two periods of time, the study uses 10 financial ratios which are broadly categorized into 4 groups: (a) profitability ratios; (b) liquidity ratios; (c) risk and solvency ratios; and (d) efficiency ratios. Next, the study used T-test in determining the significance of the differential performance of the two banks over two periods of time. By using inter-bank comparison, the study found that, conventional bank has better performance, efficient, more profitable and has greater risk as compared to Islamic bank. However, in terms of utilizing asset, Islamic bank is better than conventional bank. As an overall, conventional bank is better in much aspect due to the longer history and experience in the industry than Islamic bank that start their operation in 1983.

Stroke Severity Affects Timing: Time From Stroke Code Activation to Initial Imaging is Longer in Patients With Milder Strokes.

PubMed

Kwei, Kimberly T; Liang, John; Wilson, Natalie; Tuhrim, Stanley; Dhamoon, Mandip

2018-05-01

Optimizing the time it takes to get a potential stroke patient to imaging is essential in a rapid stroke response. At our hospital, door-to-imaging time is comprised of 2 time periods: the time before a stroke is recognized, followed by the period after the stroke code is called during which the stroke team assesses and brings the patient to the computed tomography scanner. To control for delays due to triage, we isolated the time period after a potential stroke has been recognized, as few studies have examined the biases of stroke code responders. This "code-to-imaging time" (CIT) encompassed the time from stroke code activation to initial imaging, and we hypothesized that perception of stroke severity would affect how quickly stroke code responders act. In consecutively admitted ischemic stroke patients at The Mount Sinai Hospital emergency department, we tested associations between National Institutes of Health Stroke Scale scores (NIHSS), continuously and at different cutoffs, and CIT using spline regression, t tests for univariate analysis, and multivariable linear regression adjusting for age, sex, and race/ethnicity. In our study population, mean CIT was 26 minutes, and mean presentation NIHSS was 8. In univariate and multivariate analyses comparing CIT between mild and severe strokes, stroke scale scores <4 were associated with longer response times. Milder strokes are associated with a longer CIT with a threshold effect at a NIHSS of 4.

A Prospective Cohort Quality Improvement Study to Reduce the Time to Antibiotics for New Fever in Neutropenic Pediatric Oncology Inpatients.

PubMed

Green, Adam L; Yi, Joanna; Bezler, Natalie; Pikman, Yana; Tubman, Venée N; Obeng, Esther A; O'Neil, Teresa; Mersereau, Robert; Morrissey, Lisa; Billett, Amy L

2016-01-01

Fever and neutropenia (F&N) is a pediatric oncology emergency due to the risk of disseminated infection. Quality improvement (QI) efforts to improve time to antibiotics for F&N in the emergency department have been documented, but the issue has not been studied in the established inpatient setting. We undertook a prospective cohort QI study to decrease time to antibiotics for neutropenic pediatric oncology inpatients with new fever to <60 min. Our key intervention was discussion of a plan in case of new fever, including antibiotic(s) to be started, for each patient on rounds. Timing for each step in the process, from fever identification to antibiotic administration, was measured through the electronic medical record for each fever event. The median time to antibiotics during the 3-three month intervention study period was 76.0 min, although the distribution was skewed due to several long outliers (mean 142.5, interquartile range 51-206, range 47-593 min). Time to antibiotics was significantly shorter when a fever contingency plan was documented in the most recent note than not (mean 102 vs. 254 min, P = 0.039). Over the total 2.75 year data-collection period, the quarterly percentage of patients receiving antibiotics within 60 min has improved from 35 to 65, whereas quarterly mean time to antibiotics has improved from 99 to 50 min. Daily discussion of a fever contingency plan appears effective in decreasing the time to antibiotics for neutropenic pediatric oncology inpatients with new fever, likely by circumventing the need for multi-level discussion of the antibiotic plan when fever is identified. © 2015 Wiley Periodicals, Inc.

Preliminary studies on haematological and plasmatic parameters in gilthead sea bream (Sparus aurata) held under day/night temperature variations.

PubMed

Matias, Ana C; Ribeiro, Laura; Araujo, Ravi L; Pousão-Ferreira, Pedro

2018-02-01

This study aimed to evaluate to what extent diel water temperature oscillations over a short period of time (41 h) affected haematologic and plasmatic parameters of gilthead sea bream. Sea bream juveniles (160 fish; 177.2 ± 20.9 g) were divided in two homogenous groups, experimental and control. The experimental group was exposed to water at 22.3 ± 0.6 °C between 5 a.m. and 5 p.m. and to colder water from 5 p.m. to 5 a.m. (temperature variation of 8.6 ± 0.3 °C) during 41h period, whereas for the control group, water temperature was maintained constant (22.4 ± 0.7 °C) for the same period. Fish were fed three times per day (10:30 a.m., 2 p.m., 4 p.m.). Blood was collected from fish caudal veins (n = 6) at different time points (10 a.m., 1 p.m., 5 p.m., 6:30 p.m., 8 p.m. and 10 a.m. of the following day) from each group, for haematologic (haematocrit and haemoglobin) and plasmatic (glucose, cortisol, triglycerides and total protein) determinations. All parameters studied tended to vary throughout the study period, both for experimental and control groups. Significant differences were observed between the two groups for all the studied parameters at different sampling points. These differences were observed near the influence of the cold-water period or during the cooling-water period. Results suggested that colder water temperature cycles depressed fish metabolic activity and affected the levels of the analysed blood-circulating metabolites. Overall, results suggested that stress response was similar for experimental and control groups and that gilthead sea bream were able to cope with diel water temperature variations.

Dental development in living and fossil orangutans.

PubMed

Smith, Tanya M

2016-05-01

Numerous studies have investigated molar development in extant and fossil hominoids, yet relatively little is known about orangutans, the only great ape with an extensive fossil record. This study characterizes aspects of dental development, including cuspal enamel daily secretion rate, long-period line periodicities, cusp-specific molar crown formation times and extension rates, and initiation and completion ages in living and fossil orangutan postcanine teeth. Daily secretion rate and periodicities in living orangutans are similar to previous reports, while crown formation times often exceed published values, although direct comparisons are limited. One wild Bornean individual died at 4.5 years of age with fully erupted first molars (M1s), while a captive individual and a wild Sumatran individual likely erupted their M1s around five or six years of age. These data underscore the need for additional samples of orangutans of known sex, species, and developmental environment to explore potential sources of variation in molar emergence and their relationship to life history variables. Fossil orangutans possess larger crowns than living orangutans, show similarities in periodicities, and have faster daily secretion rate, longer crown formation times, and slower extension rates. Molar crown formation times exceed reported values for other fossil apes, including Gigantopithecus blacki. When compared to African apes, both living and fossil orangutans show greater cuspal enamel thickness values and periodicities, resulting in longer crown formation times and slower extension rates. Several of these variables are similar to modern humans, representing examples of convergent evolution. Molar crown formation does not appear to be equivalent among extant great apes or consistent within living and fossil members of Pongo or Homo. Copyright © 2016 The Author. Published by Elsevier Ltd.. All rights reserved.

Periodic cycles of social outbursts of activity

NASA Astrophysics Data System (ADS)

Berestycki, H.; Rossi, L.; Rodríguez, N.

2018-01-01

We study the long-time behavior of a 2 × 2 continuous dynamical system with a time-periodic source term which is either of cooperative-type or activator-inhibitor type. This system was recently introduced in the literature [2] to model the dynamics of social outbursts and consists of an explicit field measuring the level of activity and an implicit field measuring the effective tension. The system can be used to represent a general type of phenomena in which one variable exhibits self-excitement once the other variable has reached a critical value. The time-periodic source term allows one to analyze the effect that periodic external shocks to the system play in the dynamics of the outburst of activity. For cooperative systems we prove that for small shocks the level of activity dies down whereas, as the intensity of the shocks increases, the level of activity converges to a positive periodic solution (excited cycle). We further show that in some cases there is multiplicity of excited cycles. We derive a subset of these results for the activator-inhibitor system.

Studying the Motivated Agent Through Time: Personal Goal Development During the Adult Life Span.

PubMed

Dunlop, William L; Bannon, Brittany L; McAdams, Dan P

2017-04-01

This research examined the rank-order and mean-level consistency of personal goals at two periods in the adult life span. Personal goal continuity was considered among a group of young adults (N = 145) who reported their goals three times over a 3-year period and among a group of midlife adults (N = 163) who specified their goals annually over a 4-year period. Goals were coded for a series of motive-based (viz., achievement, affiliation, intimacy, power) and domain-based (viz., finance, generativity, health, travel) categories. In both samples, we noted a moderate degree of rank-order consistency across assessment periods. In addition, the majority of goal categories exhibited a high degree of mean-level consistency. The results of this research suggest that (a) the content of goals exhibits a modest degree of rank-order consistency and a substantial degree of mean-level consistency over time, and (b) considering personality continuity and development as manifest via goals represents a viable strategy for personality psychologists. © 2015 Wiley Periodicals, Inc.

Apomorphine Subcutaneous Injection for the Management of Morning Akinesia in Parkinson's Disease.

PubMed

Isaacson, Stuart; Lew, Mark; Ondo, William; Hubble, Jean; Clinch, Thomas; Pagan, Fernando

2017-01-01

In patients with motor fluctuations complicating Parkinson's disease (PD), delays in time-to-ON with levodopa are common. This open-label study aimed to assess the effect of apomorphine on time-to-ON in PD patients with morning akinesia. The safety population included 127 enrolled patients, and the full analysis set (FAS) included 88 patients. Patients completed a 7-day levodopa baseline period recording their time-to-ON following each morning dose of levodopa. Patients were titrated to an optimal dose of apomorphine (2-6 mg) while taking trimethobenzamide antiemetic therapy. Apomorphine was injected each morning for a 7-day treatment period and time-to-ON was self-recorded in 5-minute blocks. The primary efficacy variable was time-to-ON in the apomorphine treatment period versus the baseline levodopa period. Secondary assessments included and global impression scales. Safety and tolerability were assessed through adverse events (AEs). Patients receiving apomorphine achieved mean ± standard deviation (SD) time-to-ON 23.72 ± 14.55 minutes, reduced from 60.86 ± 18.11 minutes with levodopa ( P < 0.0001). Dose failures (defined as time-to-ON >60 minutes) were more commonly reported with levodopa versus apomorphine (46% vs. 7% of diary entries, respectively). Secondary endpoints supported the primary efficacy findings, with significant improvements from levodopa baseline to apomorphine treatment period (all P < 0.0001). The most common AEs were nausea and dizziness. Most patients who discontinued because of AEs did so in the titration phase. Apomorphine injections significantly reduced time-to-ON in PD patients experiencing delayed onset of their morning levodopa dose, and was well tolerated in most patients. After apomorphine treatment, fluctuating patients with morning akinesia experienced rapid and reliable improvement of time-to-ON.

Long-term consequences of variation in timing and manner of fry introduction on juvenile Atlantic salmon (Salmo salar) growth, survival, and life-history expression

USGS Publications Warehouse

Letcher, B.H.; Dubreuil, T.; O'Donnell, M. J.; Obedzinski, M.; Griswold, K.; Nislow, K.H.

2004-01-01

We tested the influence of introduction time and the manner of introduction on growth, survival, and life-history expression of Atlantic salmon (Salmo salar). Introduction treatments included three fry stocking times and stream rearing of embryos. Despite poor growth conditions during the early stocking period, early-stocked fish were larger throughout the entire study period, likely the result of prior residence advantage. This interpretation was reinforced by the laboratory study, where early-stocked fish outgrew late-stocked fish when reared together, but not when they were reared separately. In contrast to growth, abundance of stocked fish was greatest for fish stocked during the middle period, and this stocking group produced the greatest number of smolts. Despite smaller size, survival of stream-incubated fish was generally greater than survival of stocked fish. Introduction timing had a pronounced effect on smolt age but a weak effect on extent of parr maturation. Overall, these observations indicate that small differences (???2 weeks) in introduction time can have long-term effects on size, survival, and life-history expression. Results suggest stabilizing selection on introduction times, mediated by the interaction between prior residence (advantage to fish introduced earlier) and habitat suitability (advantage to fish introduced later). ?? 2004 NRC Canada.

Individual and system influences on waiting time for substance abuse treatment.

PubMed

Carr, Carey J A; Xu, Jiangmin; Redko, Cristina; Lane, D Timothy; Rapp, Richard C; Goris, John; Carlson, Robert G

2008-03-01

Waiting time is a contemporary reality of many drug abuse treatment programs, resulting in substantial problems for substance users and society. Individual and system factors that influence waiting time are diverse and may vary at different points in the treatment continuum. This study assessed waiting time preceding clinical assessment at a centralized intake unit and during the period after the assessment but before treatment entry. The present study included 577 substance abusers who were enrolled in a large clinical trial of two brief treatment interventions in a midsize metropolitan area in Ohio. Bivariate analyses identified individual and system factors that influenced preassessment and postassessment waiting time, as well as total wait to treatment services. Multivariate analyses demonstrated that longer wait time for an assessment is influenced by being court referred, less belief in having a substance abuse problem, and less desire for change. A shorter wait to actually enter treatment is predicted by having a case manager, being more ready for treatment, and having less severe employment and alcohol problems. The different influences present during the two waiting periods suggest that assessment and treatment programs need to implement system changes and entry enhancement interventions that are specific to the needs of substance abusers at each waiting period.

Buying time-the immune system determinants of the incubation period to respiratory viruses.

PubMed

Hermesh, Tamar; Moltedo, Bruno; López, Carolina B; Moran, Thomas M

2010-11-01

Respiratory viruses cause disease in humans characterized by an abrupt onset of symptoms. Studies in humans and animal models have shown that symptoms are not immediate and appear days or even weeks after infection. Since the initial symptoms are a manifestation of virus recognition by elements of the innate immune response, early virus replication must go largely undetected. The interval between infection and the emergence of symptoms is called the incubation period and is widely used as a clinical score. While incubation periods have been described for many virus infections the underlying mechanism for this asymptomatic phase has not been comprehensively documented. Here we review studies of the interaction between human pathogenic respiratory RNA viruses and the host with a particular emphasis on the mechanisms used by viruses to inhibit immunity. We discuss the concept of the "stealth phase", defined as the time between infection and the earliest detectable inflammatory response. We propose that the "stealth phase" phenomenon is primarily responsible for the suppression of symptoms during the incubation period and results from viral antagonism that inhibits major pathways of the innate immune system allowing an extended time of unhindered virus replication.

Reaching multi-nanosecond timescales in combined QM/MM molecular dynamics simulations through parallel horsetail sampling.

PubMed

Martins-Costa, Marilia T C; Ruiz-López, Manuel F

2017-04-15

We report an enhanced sampling technique that allows to reach the multi-nanosecond timescale in quantum mechanics/molecular mechanics molecular dynamics simulations. The proposed technique, called horsetail sampling, is a specific type of multiple molecular dynamics approach exhibiting high parallel efficiency. It couples a main simulation with a large number of shorter trajectories launched on independent processors at periodic time intervals. The technique is applied to study hydrogen peroxide at the water liquid-vapor interface, a system of considerable atmospheric relevance. A total simulation time of a little more than 6 ns has been attained for a total CPU time of 5.1 years representing only about 20 days of wall-clock time. The discussion of the results highlights the strong influence of the solvation effects at the interface on the structure and the electronic properties of the solute. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Environmental and social determinants of population vulnerability to Zika virus emergence at the local scale.

PubMed

Rees, Erin E; Petukhova, Tatiana; Mascarenhas, Mariola; Pelcat, Yann; Ogden, Nicholas H

2018-05-08

Zika virus (ZIKV) spread rapidly in the Americas in 2015. Targeting effective public health interventions for inhabitants of, and travellers to and from, affected countries depends on understanding the risk of ZIKV emergence (and re-emergence) at the local scale. We explore the extent to which environmental, social and neighbourhood disease intensity variables influenced emergence dynamics. Our objective was to characterise population vulnerability given the potential for sustained autochthonous ZIKV transmission and the timing of emergence. Logistic regression models estimated the probability of reporting at least one case of ZIKV in a given municipality over the course of the study period as an indicator for sustained transmission; while accelerated failure time (AFT) survival models estimated the time to a first reported case of ZIKV in week t for a given municipality as an indicator for timing of emergence. Sustained autochthonous ZIKV transmission was best described at the temporal scale of the study period (almost one year), such that high levels of study period precipitation and low mean study period temperature reduced the probability. Timing of ZIKV emergence was best described at the weekly scale for precipitation in that high precipitation in the current week delayed reporting. Both modelling approaches detected an effect of high poverty on reducing/slowing case detection, especially when inter-municipal road connectivity was low. We also found that proximity to municipalities reporting ZIKV had an effect to reduce timing of emergence when located, on average, less than 100 km away. The different modelling approaches help distinguish between large temporal scale factors driving vector habitat suitability and short temporal scale factors affecting the speed of spread. We find evidence for inter-municipal movements of infected people as a local-scale driver of spatial spread. The negative association with poverty suggests reduced case reporting in poorer areas. Overall, relatively simplistic models may be able to predict the vulnerability of populations to autochthonous ZIKV transmission at the local scale.

Stabilizing the long-time behavior of the forced Navier-Stokes and damped Euler systems by large mean flow

NASA Astrophysics Data System (ADS)

Cyranka, Jacek; Mucha, Piotr B.; Titi, Edriss S.; Zgliczyński, Piotr

2018-04-01

The paper studies the issue of stability of solutions to the forced Navier-Stokes and damped Euler systems in periodic boxes. It is shown that for large, but fixed, Grashoff (Reynolds) number the turbulent behavior of all Leray-Hopf weak solutions of the three-dimensional Navier-Stokes equations, in periodic box, is suppressed, when viewed in the right frame of reference, by large enough average flow of the initial data; a phenomenon that is similar in spirit to the Landau damping. Specifically, we consider an initial data which have large enough spatial average, then by means of the Galilean transformation, and thanks to the periodic boundary conditions, the large time independent forcing term changes into a highly oscillatory force; which then allows us to employ some averaging principles to establish our result. Moreover, we also show that under the action of fast oscillatory-in-time external forces all two-dimensional regular solutions of the Navier-Stokes and the damped Euler equations converge to a unique time-periodic solution.

Self-pulsations and excitability in optically injected quantum-dot lasers: Impact of the excited states and spontaneous emission noise

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

Olejniczak, Lukasz; SUPELEC, OPTEL, and LMOPS EA 4423; Panajotov, Krassimir

2010-08-15

We study the dynamics of an optically injected quantum-dot laser accounting for excited states. Mapping of the bifurcations in the plane frequency detuning vs. injection strength shows that the relaxation rate scales the regions of locking and single- and double-period solutions, while the capture rate has a minor effect. Within the regions of time-periodic solutions, close to the saddle-node bifurcation boundary, we identify subregions where the output signal resembles excitable pulses as a result of the bottleneck phenomenon. We show that such emission is determined mainly by fluctuations in the occupation of the excited states. The interpulse time follows anmore » inverse square root scaling law as a function of the detuning. In a deterministic system the pulses are periodic regardless of the detuning, but in the presence of noise, close to the locking region, the interpulse time follows a positively skewed normal distribution. For a fixed frequency detuning, increasing the noise strength can shift the mean of the interpulse time distribution and make the pulsations more periodic.« less

Stochastic entrainment of a stochastic oscillator.

PubMed

Wang, Guanyu; Peskin, Charles S

2015-01-01

In this work, we consider a stochastic oscillator described by a discrete-state continuous-time Markov chain, in which the states are arranged in a circle, and there is a constant probability per unit time of jumping from one state to the next in a specified direction around the circle. At each of a sequence of equally spaced times, the oscillator has a specified probability of being reset to a particular state. The focus of this work is the entrainment of the oscillator by this periodic but stochastic stimulus. We consider a distinguished limit, in which (i) the number of states of the oscillator approaches infinity, as does the probability per unit time of jumping from one state to the next, so that the natural mean period of the oscillator remains constant, (ii) the resetting probability approaches zero, and (iii) the period of the resetting signal approaches a multiple, by a ratio of small integers, of the natural mean period of the oscillator. In this distinguished limit, we use analytic and numerical methods to study the extent to which entrainment occurs.

Terrestrial Waters and Sea Level Variations on Interannual Time Scale

NASA Technical Reports Server (NTRS)

Llovel, W.; Becker, M.; Cazenave, A.; Jevrejeva, S.; Alkama, R.; Decharme, B.; Douville, H.; Ablain, M.; Beckley, B.

2011-01-01

On decadal to multi-decadal time scales, thermal expansion of sea waters and land ice loss are the main contributors to sea level variations. However, modification of the terrestrial water cycle due to climate variability and direct anthropogenic forcing may also affect sea level. For the past decades, variations in land water storage and corresponding effects on sea level cannot be directly estimated from observations because these are almost non-existent at global continental scale. However, global hydrological models developed for atmospheric and climatic studies can be used for estimating total water storage. For the recent years (since mid-2002), terrestrial water storage change can be directly estimated from observations of the GRACE space gravimetry mission. In this study, we analyse the interannual variability of total land water storage, and investigate its contribution to mean sea level variability at interannual time scale. We consider three different periods that, each, depend on data availability: (1) GRACE era (2003-2009), (2) 1993-2003 and (3) 1955-1995. For the GRACE era (period 1), change in land water storage is estimated using different GRACE products over the 33 largest river basins worldwide. For periods 2 and 3, we use outputs from the ISBA-TRIP (Interactions between Soil, Biosphere, and Atmosphere-Total Runoff Integrating Pathways) global hydrological model. For each time span, we compare change in land water storage (expressed in sea level equivalent) to observed mean sea level, either from satellite altimetry (periods 1 and 2) or tide gauge records (period 3). For each data set and each time span, a trend has been removed as we focus on the interannual variability. We show that whatever the period considered, interannual variability of the mean sea level is essentially explained by interannual fluctuations in land water storage, with the largest contributions arising from tropical river basins.

Intern Programs

Science.gov Websites

, engineering and computing. Working with Fermilab scientists or engineers, interns have an opportunity to four quarters at Fermilab, alternating periods of full-time study at their schools with full-time

Relationship between cutoff frequency and accuracy in time-interval photon statistics applied to oscillating signals

NASA Astrophysics Data System (ADS)

Rebolledo, M. A.; Martinez-Betorz, J. A.

1989-04-01

In this paper the accuracy in the determination of the period of an oscillating signal, when obtained from the photon statistics time-interval probability, is studied as a function of the precision (the inverse of the cutoff frequency of the photon counting system) with which time intervals are measured. The results are obtained by means of an experiment with a square-wave signal, where the Fourier or square-wave transforms of the time-interval probability are measured. It is found that for values of the frequency of the signal near the cutoff frequency the errors in the period are small.

50 CFR 221.3 - How are time periods computed?

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false How are time periods computed? 221.3 Section 221.3 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE, NATIONAL OCEANIC AND ATMOSPHERIC... Provisions § 221.3 How are time periods computed? (a) General. Time periods are computed as follows: (1) The...

Have antiepileptic drug prescription claims changed following the FDA suicidality warning? An evaluation in a state Medicaid program.

PubMed

Mittal, Manish; Harrison, Donald L; Miller, Michael J; Farmer, Kevin C; Thompson, David M; Ng, Yu-Tze

2014-05-01

In January 2008, the Food and Drug Administration (FDA) communicated concerns and, in May 2009, issued a warning about an increased risk of suicidality for all antiepileptic drugs (AEDs). This research evaluated the association between the FDA suicidality communications and the AED prescription claims among members with epilepsy and/or psychiatric disorder. A longitudinal interrupted time-series design was utilized to evaluate Oklahoma Medicaid claims data from January 2006 through December 2009. The study included 9289 continuously eligible members with prevalent diagnoses of epilepsy and/or psychiatric disorder and at least one AED prescription claim. Trends, expressed as monthly changes in the log odds of AED prescription claims, were compared across three time periods: before (January 2006 to January 2008), during (February 2008 to May 2009), and after (June 2009 to December 2009) the FDA warning. Before the FDA warning period, a significant upward trend of AED prescription claims of 0.01% per month (99% CI: 0.008% to 0.013%, p<0.0001) was estimated. In comparison to the prewarning period, no significant change in trend was detected during (-20.0%, 99% CI: -70.0% to 30.0%, p=0.34) or after (80.0%, 99% CI: -20.0% to 200.0%, p=0.03) the FDA warning period. After stratification, no diagnostic group (i.e., epilepsy alone, epilepsy and comorbid psychiatric disorder, and psychiatric disorder alone) experienced a significant change in trend during the entire study period (p>0.01). During the time period considered, the FDA AED-related suicidality warning does not appear to have significantly affected prescription claims of AED medications for the study population. Copyright © 2014 Elsevier Inc. All rights reserved.

Deformation of the self-adjusting file on simulated curved root canals: a time-dependent study.

PubMed

Akçay, Ilgın; Yiğit-Özer, Senem; Adigüzel, Özkan; Kaya, Sadulah

2011-11-01

This study examined the surface changes of self-adjusting file after operating in different degrees of canal curvatures with a fixed radius of curvature in different operation intervals. Artificial canals were manufactured in a 5-mm radius of curvature with 45° and 60° angles of curvature. Forty self-adjusting files were divided into 2 groups and submitted to functional fatigue to failure. Twenty files were tested using the 45° angle and the remaining 20 were tested using the 60° angle at 4 minutes for 7 periods in a total of 28 minutes. The average time frame for each 4-minute inspection period was considered as the moment of failure at 2, 6, 10, 14, 18, 22, and 26 minutes, respectively. Instruments were evaluated using scanning electron microscopy to characterize the material under study. The lattice detachment began at the second period for both groups and continued to increase along with the ongoing testing time. The detachment that occurred in 60° canal curvature was higher at the third and fourth periods when compared with the 45° group (P < .05). For both groups, during the third period, detachment of the arch of the lattice was only one sided; however, this deformation was severe between the fourth and sixth periods with a 2-sided detachment, which was easier to separate. The rough surface became smooth after usage. No full separation of the file was evident for both groups. In multirooted teeth with severely curved root canals, using more than one self-adjusting file might be recommended to prevent lattice detachment. Copyright © 2011 Mosby, Inc. All rights reserved.

THE EFFECT OF A DYNAMIC INNER HELIOSHEATH THICKNESS ON COSMIC-RAY MODULATION

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

Manuel, R.; Ferreira, S. E. S.; Potgieter, M. S., E-mail: rexmanuel@live.com

2015-02-01

The time-dependent modulation of galactic cosmic rays in the heliosphere is studied over different polarity cycles by computing 2.5 GV proton intensities using a two-dimensional, time-dependent modulation model. By incorporating recent theoretical advances in the relevant transport parameters in the model, we showed in previous work that this approach gave realistic computed intensities over a solar cycle. New in this work is that a time dependence of the solar wind termination shock (TS) position is implemented in our model to study the effect of a dynamic inner heliosheath thickness (the region between the TS and heliopause) on the solar modulationmore » of galactic cosmic rays. The study reveals that changes in the inner heliosheath thickness, arising from a time-dependent shock position, does affect cosmic-ray intensities everywhere in the heliosphere over a solar cycle, with the smallest effect in the innermost heliosphere. A time-dependent TS position causes a phase difference between the solar activity periods and the corresponding intensity periods. The maximum intensities in response to a solar minimum activity period are found to be dependent on the time-dependent TS profile. It is found that changing the width of the inner heliosheath with time over a solar cycle can shift the time of when the maximum or minimum cosmic-ray intensities occur at various distances throughout the heliosphere, but more significantly in the outer heliosphere. The time-dependent extent of the inner heliosheath, as affected by solar activity conditions, is thus an additional time-dependent factor to be considered in the long-term modulation of cosmic rays.« less

Instrument for Study of Microbial Thermal Inactivation

PubMed Central

Dickerson, R. W.; Read, R. B.

1968-01-01

An instrument was designed for the study of thermal inactivation of microorganisms using heating times of less than 1 sec. The instrument operates on the principle of rapid automatic displacement of the microorganism to and from a saturated steam atmosphere, and the operating temperature range is 50 to 90 C. At a temperature of 70 C, thermometric lag (time required to respond to 63.2% of a step change) of the fluid sample containing microorganisms was 0.12 sec. Heating time required to heat the sample to within 0.1 C of the exposure temperature was less than 1 sec, permitting exposure periods as brief as 1 sec, provided the proper corrections are made for the lethal effect of heating. The instrument is most useful for heat exposure periods of less than 5 min, and, typically, more than 500 samples can be processed for microbial inactivation determinations within an 8-hr period. Images Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 7 Fig. 8 PMID:4874466

Severe musculoskeletal time-loss injuries and symptoms of common mental disorders in professional soccer: a longitudinal analysis of 12-month follow-up data.

PubMed

Kiliç, Ö; Aoki, H; Goedhart, E; Hägglund, M; Kerkhoffs, G M M J; Kuijer, P P F M; Waldén, M; Gouttebarge, V

2018-03-01

Psychological factors have shown to be predictors of injury in professional football. However, it seems that this is a two-way relationship, as severe musculoskeletal time-loss injuries have shown to be associated with the onset of symptoms of common mental disorders (CMD). There is no longitudinal study performed exploring this interaction between symptoms of CMD and injuries. The purpose of this study was to explore the interaction between severe musculoskeletal time-loss injuries and symptoms of CMD in professional football players over a 12-month period. Players were recruited by their national players' unions in five European countries. Symptoms of CMD included in the study were related to distress, anxiety/depression, sleep disturbance and adverse alcohol use. A total of 384 professional football players were enrolled in the study, of whom 262 (68%) completed the 12-month follow-up period. The mean age of the participants at baseline was 27 ± 5 years, and they had played professional football for 8 ± 5 years on average. Symptoms of CMD at baseline were not associated with the onset of severe musculoskeletal time-loss injuries during the follow-up period with relative risks (and 95% CI) ranging from 0.6 (0.3-1.0) to 1.0 (0.5-2.2). In contrast, severe musculoskeletal time-loss injuries reported at baseline were associated with the onset of symptoms of CMD during the follow-up period with relative risks ranging from 1.8 (0.8-3.7) to 6.9 (4.0-11.9). No relationship was found between symptoms of CMD and the onset of severe musculoskeletal time-loss injuries. However, professional football players who suffered from severe musculoskeletal time-loss injuries are likely to develop subsequent symptoms of CMD. This study emphasizes the need for an interdisciplinary medical approach, which not only focuses on the physical but also on the mental health of professional football players. An early identification of players at risk of symptoms of CMD, such as those suffering from severe musculoskeletal injuries, creates the opportunity for an interdisciplinary clinical medical team to treat the players timely and adequately. Prospective cohort study, Level II.

Time-series modeling of long-term weight self-monitoring data.

PubMed

Helander, Elina; Pavel, Misha; Jimison, Holly; Korhonen, Ilkka

2015-08-01

Long-term self-monitoring of weight is beneficial for weight maintenance, especially after weight loss. Connected weight scales accumulate time series information over long term and hence enable time series analysis of the data. The analysis can reveal individual patterns, provide more sensitive detection of significant weight trends, and enable more accurate and timely prediction of weight outcomes. However, long term self-weighing data has several challenges which complicate the analysis. Especially, irregular sampling, missing data, and existence of periodic (e.g. diurnal and weekly) patterns are common. In this study, we apply time series modeling approach on daily weight time series from two individuals and describe information that can be extracted from this kind of data. We study the properties of weight time series data, missing data and its link to individuals behavior, periodic patterns and weight series segmentation. Being able to understand behavior through weight data and give relevant feedback is desired to lead to positive intervention on health behaviors.

Exponential synchronization of chaotic systems with time-varying delays and parameter mismatches via intermittent control.

PubMed

Cai, Shuiming; Hao, Junjun; Liu, Zengrong

2011-06-01

This paper studies the synchronization of coupled chaotic systems with time-varying delays in the presence of parameter mismatches by means of periodically intermittent control. Some novel and useful quasisynchronization criteria are obtained by using the methods which are different from the techniques employed in the existing works, and the derived results are less conservative. Especially, a strong constraint on the control width that the control width should be larger than the time delay imposed by the current references is released in this paper. Moreover, our results show that the synchronization criteria depend on the ratio of control width to control period, but not the control width or the control period. Finally, some numerical simulations are given to show the effectiveness of the theoretical results.

Initial results from SKiYMET meteor radar at Thumba (8.5°N, 77°E): 2. Gravity wave observations in the MLT region

NASA Astrophysics Data System (ADS)

Kumar, Karanam Kishore; Antonita, T. Maria; Shelbi, S. T.

2007-12-01

In the present communication, allSKy interferometric METeor (SKiYMET) radar observations of gravity wave activity in the mesosphere lower thermosphere (MLT) region over Thumba (8.5°N, 77°E) are presented. The present meteor radar system provides hourly zonal and meridional winds in the MLT region, which can be readily used for studying the tides, planetary waves, gravity waves of periods 2-6 hours, and other long period oscillations in this region. However, these hourly winds are not sufficient for studying short period gravity waves having periods less than an hour, which demand high temporal resolution measurements. Even though the winds are estimated on an hourly basis, information such as zenith angle, azimuth angle, and radial velocity of each detected meteor are archived. Using these details of the meteor, an algorithm is developed to obtain the 15-min temporal resolution wind data. The output of the algorithm is compared with hourly wind data, and it showed a good agreement during the high meteor shower periods. Most of the times high meteor counts are observed during late night and early morning hours (local) over this latitude. Continuous wind measurements during the high meteor shower periods are used for studying the gravity wave activity in the MLT region. As the wave activity is intermittent and nonstationary, wavelet analysis has been used for delineating the wave features. The results showed the upward propagating intermittent gravity waves with periods 1-2 and 4-5 hours. The new aspect of the present communication is the usage of meteor radar for gravity wave studies for the first time over this latitude and studying their seasonal variability.

40 CFR 141.602 - System specific studies.

Code of Federal Regulations, 2014 CFR

2014-07-01

... the storage facility with the highest residence time in each pressure zone, and a time series graph of... (a)(2)(ii) of this section, and a 24-hour time series graph of residence time for each subpart V...-compliance results generated during the time period beginning with the first reported result and ending with...

40 CFR 141.602 - System specific studies.

Code of Federal Regulations, 2010 CFR

2010-07-01

... the storage facility with the highest residence time in each pressure zone, and a time series graph of... (a)(2)(ii) of this section, and a 24-hour time series graph of residence time for each subpart V... compliance and non-compliance results generated during the time period beginning with the first reported...

40 CFR 141.602 - System specific studies.

Code of Federal Regulations, 2012 CFR

2012-07-01

... the storage facility with the highest residence time in each pressure zone, and a time series graph of... (a)(2)(ii) of this section, and a 24-hour time series graph of residence time for each subpart V... compliance and non-compliance results generated during the time period beginning with the first reported...

40 CFR 141.602 - System specific studies.

Code of Federal Regulations, 2013 CFR

2013-07-01

... the storage facility with the highest residence time in each pressure zone, and a time series graph of... (a)(2)(ii) of this section, and a 24-hour time series graph of residence time for each subpart V... compliance and non-compliance results generated during the time period beginning with the first reported...

40 CFR 141.602 - System specific studies.

Code of Federal Regulations, 2011 CFR

2011-07-01

... the storage facility with the highest residence time in each pressure zone, and a time series graph of... (a)(2)(ii) of this section, and a 24-hour time series graph of residence time for each subpart V... compliance and non-compliance results generated during the time period beginning with the first reported...

Narrow log-periodic modulations in non-Markovian random walks

NASA Astrophysics Data System (ADS)

Diniz, R. M. B.; Cressoni, J. C.; da Silva, M. A. A.; Mariz, A. M.; de Araújo, J. M.

2017-12-01

What are the necessary ingredients for log-periodicity to appear in the dynamics of a random walk model? Can they be subtle enough to be overlooked? Previous studies suggest that long-range damaged memory and negative feedback together are necessary conditions for the emergence of log-periodic oscillations. The role of negative feedback would then be crucial, forcing the system to change direction. In this paper we show that small-amplitude log-periodic oscillations can emerge when the system is driven by positive feedback. Due to their very small amplitude, these oscillations can easily be mistaken for numerical finite-size effects. The models we use consist of discrete-time random walks with strong memory correlations where the decision process is taken from memory profiles based either on a binomial distribution or on a delta distribution. Anomalous superdiffusive behavior and log-periodic modulations are shown to arise in the large time limit for convenient choices of the models parameters.

Behavioral study of ultradian activity periods of mice enclosed in experimental cages of different dimensions

NASA Technical Reports Server (NTRS)

Guillot, A.

1982-01-01

Male mice are enclosed in cages of different dimensions (cage A - 23x8x8 cm., cage B - 36x27x17 cm.), in an alternating light/dark regimen, at an ambient temperature of 22 to 23 C. The successions of the behavioral sequences of ultradian activity periods are noticed by direct observation during 11 consecutive hours in light. The experimental situation modifies the mean duration time and the behavioral organization of each activity period. However, the comparison of the overall activity time lengths and the comparison of the overall behavioral frequencies suggest that the energy spent per mouse is constant.

Differences in Mucociliary activity of volunteers undergoing Ramadan versus Nineveh fasting.

PubMed

Develioglu, Omer Necati; Sirazi, Sait; Topak, Murat; Purisa, Sevim; Kulekci, Mehmet

2013-05-01

This study, aimed to evaluate the difference in mucociliary clearance among volunteers who underwent Ramadan versus Nineveh fasting regimens as well as the difference between the fasting period and 4 weeks following the fasting period in both groups. In this study, two different fasting groups were established: Ramadan (fasting for an average of 15 h for 29 consecutive days, n = 40) and Nineveh (60 h of nonstop fasting, n = 26). Subjects in each group underwent saccharin testing twice: at the end of the fasting period prior to resumption of eating and at 4 weeks after the end of Ramadan or Nineveh fasting. Statistical analysis was performed using the Mann-Whitney U-test, Wilcoxon, Chi-square, and paired t test. A p value less than 0.05 was considered statistically significant. Forty subjects who underwent Ramadan fasting and 26 subjects who underwent Nineveh fasting were included in this study. Of the 66 study participants, 34 (51.5 %) were men and 32 (48.5 %) were women. Their median age was 31 years (range 17-70 years) for Nineveh fasting subjects and 40 years (range 17-70 years) for Ramadan fasting subjects. Chi-square tests revealed no significant difference between the Ramadan and Nineveh fasting groups in gender (p = 0.418), and the Mann-Whitney U-test showed no difference in age. A statistically significant difference was found in the mucociliary clearance time between the Nineveh fasting and non-fasting periods (p = 0.013). Using Wilcoxon signed-rank tests, we found no significant difference in the mucociliary clearance time between the Ramadan fasting and control (4 weeks after the fasting period) periods (p = 0.121). The percentage difference between the fasting and control periods was similar between groups and was not statistically significant for the Ramadan and Nineveh fasting groups (p = 0.086). The results of the present study indicated that long-term fasting with hypohydration contributed to the deterioration of nasal mucociliary clearance. Our data indicate that optimal hydration, sleep patterns, and fasting times contribute to proper mucociliary clearance.

Decision support during electronic prescription to stem antibiotic overuse for acute respiratory infections: a long-term, quasi-experimental study.

PubMed

Gifford, Jeneen; Vaeth, Elisabeth; Richards, Katherine; Siddiqui, Tariq; Gill, Christine; Wilson, Lucy; DeLisle, Sylvain

2017-07-31

Interventions to support decision-making can reduce inappropriate antibiotic use for acute respiratory infections (ARI), but they may not be sustainable. The objective of the study is to evaluate the long-term effectiveness of a clinical decision-support system (CDSS) interposed at the time of electronic (e-) prescriptions for selected antibiotics. This is a retrospective, observational intervention study, conducted within a large, statewide Veterans Affairs health system. Participants are outpatients with an initial visit for ARI. A CDSS was deployed upon e-prescription of selected antibiotics during the study period. From 01/2004 to 05/2006 (pre-withdrawal period), the CDSS targeted azithromycin and the fluoroquinolone gatifloxacin. From 05/2006 to 12/2011 (post-withdrawal period), the CDSS was retained for azithromycin but withdrawn for the fluoroquinolone. A manual record review was conducted to determine concordance of antibiotic prescription with ARI treatment guidelines. Of 1131 included ARI visits, 380 (33.6%) were guideline-concordant. For azithromycin, concordance did not change between the pre- and post-withdrawal periods, and adjusted odds of concordance was 8.8 for the full study period, compared to unrestricted antibiotics. For fluoroquinolones, guideline concordance decreased from 88.6% (39 of 44 visits) to 51.3% (59 of 115 visits), pre- vs. post-withdrawal periods (p < 0.005). The adjusted odds of concordance compared to "All Other Antibiotics" visits decreased from 24.4 (95% CI 9.0-66.3) pre-withdrawal to 5.5 (95% CI 3.5-8.8) post-withdrawal (p = .008). Concordance did not change between those same time periods for antibiotics that were never subjected to the intervention ("All Other Antibiotics"). A CDSS interposed at the time of e-prescription of selected antibiotics can shift their use toward ARI treatment guidelines, and this effect can be maintained over the long term as long as the CDSS remains in place. Removal of the CDSS after 3.5 years of implementation resulted in a rise in guideline-discordant antibiotic use.

Inception of the ‘endocarditis team’ is associated with improved survival in patients with infective endocarditis who are managed medically: findings from a before-and-after study

PubMed Central

Kaura, Amit; Byrne, Jonathan; Fife, Amanda; Deshpande, Ranjit; Baghai, Max; Gunning, Margaret; Whitaker, Donald; Monaghan, Mark; MacCarthy, Philip A; Wendler, Olaf; Dworakowski, Rafal

2017-01-01

Objective Despite improvements in its management, infective endocarditis (IE) is associated with poor survival. The aim of this study was to evaluate the impact of a multidisciplinary endocarditis team (ET), including a cardiologist, microbiologist and a cardiac surgeon, on the outcome of patients with acute IE according to medical or surgical treatment strategies. Methods We conducted an observational before-and-after study of 196 consecutive patients with definite IE, who were treated at a tertiary reference centre between 2009 and 2015. The study was divided into two periods: period 1, before the formation of the ET (n=101), and period 2, after the formation of the ET (n=95). The role of the ET included regular multidisciplinary team meetings to confirm diagnosis, inform the type and duration of antibiotic therapy and recommend early surgery, when indicated, according to European guidelines. Results The patient demographics and predisposing conditions for IE were comparable between the two study periods. In the time period following the introduction of the ET, there was a reduction in both the time to commencement of IE-specific antibiotic therapy (4.0±4.0 days vs 2.5±3.2 days; P=0.004) and the time from suspected IE to surgery (7.8±7.3 days vs 5.3±4.2 days; P=0.004). A 12-month Kaplan-Meier survival for patients managed medically was 42.9% in the pre-ET period and 66.7% in the post-ET period (P=0.03). The involvement of the ET was a significant independent predictor of 1-year survival in patients managed medically (HR 0.24, 95% CI 0.07 to 0.87; P=0.03). Conclusions A standardised multidisciplinary team approach may lead to earlier diagnosis of IE, more appropriate individualised management strategies, expedited surgery, where indicated, and improved survival in those patients chosen for medical management, supporting the recent change in guidelines to recommend the use of a multidisciplinary team in the care of patients with IE. PMID:29344368

A case study of highly time-resolved evolution of aerosol chemical composition and optical properties during severe haze pollution in Shanghai, China

NASA Astrophysics Data System (ADS)

Zhu, W.; Cheng, Z.; Lou, S.

2017-12-01

Despite of extensive efforts into characterization of the sources in severe haze pollution periods in the megacity of Shanghai, the study of aerosol composition, mass-size distribution and optical properties to PM1 in the pollution periods remain poorly understood. Here we conducted a 47days real-time measurement of submicron aerosol (PM1) composition and size distribution by a High-Resolution Time-of-Flight Aerosol Mass spectrometer (HR-TOF-AMS), particle light scattering by a Cavity Attenuated Phase Shift ALBedo monitor (CAPS-ALB) and Photoacoustic Extinctionmeter (PAX) in Shanghai, China, from November 28, 2016 to January 12, 2017. The average PM1 concentration was 85.9(±14.7) μg/m3 during the pollution period, which was nearly 4 times higher than that of clean period. Increased scattering coefficient during EP was associated with higher secondary inorganic aerosols and organics. We also observed organics mass size distribution for different pollution extents showing different distribution characteristics. There were no obvious differences for ammonium nitrate and ammonium sulfate among the pollution periods, which represented single peak distributions, and peaks ranged at 650-700nm and 700nm, respectively. A strong relationship can be expected between PM1 compounds mass concentration size distribution and scattering coefficient, suggesting that chemical composition, size distribution of the particles and their variations could also contribute to the extinction coefficients. Organics and secondary inorganic species to particle light scattering were quantified. The results showed that organics and ammonium nitrate were the largest contribution to scattering coefficients of PM1. The contribution of (NH4)2SO4 to the light scattering exceeded that of NH4NO3 during clean period due to the enhanced sulfate concentrations. Our results elucidate substantial changes of aerosol composition, formation mechanisms, size distribution and optical properties due to local emissions, region transports and meteorological changes in the pollution period.

Review of Epidemiological Studies of Drinking-Water Turbidity in Relation to Acute Gastrointestinal Illness.

PubMed

De Roos, Anneclaire J; Gurian, Patrick L; Robinson, Lucy F; Rai, Arjita; Zakeri, Issa; Kondo, Michelle C

2017-08-17

Turbidity has been used as an indicator of microbiological contamination of drinking water in time-series studies attempting to discern the presence of waterborne gastrointestinal illness; however, the utility of turbidity as a proxy exposure measure has been questioned. We conducted a review of epidemiological studies of the association between turbidity of drinking-water supplies and incidence of acute gastrointestinal illness (AGI), including a synthesis of the overall weight of evidence. Our goal was to evaluate the potential for causal inference from the studies. We identified 14 studies on the topic (distinct by region, time period and/or population). We evaluated each study with regard to modeling approaches, potential biases, and the strength of evidence. We also considered consistencies and differences in the collective results. Positive associations between drinking-water turbidity and AGI incidence were found in different cities and time periods, and with both unfiltered and filtered supplies. There was some evidence for a stronger association at higher turbidity levels. The studies appeared to adequately adjust for confounding. There was fair consistency in the notable lags between turbidity measurement and AGI identification, which fell between 6 and 10 d in many studies. The observed associations suggest a detectable incidence of waterborne AGI from drinking water in the systems and time periods studied. However, some discrepant results indicate that the association may be context specific. Combining turbidity with seasonal and climatic factors, additional water quality measures, and treatment data may enhance predictive modeling in future studies. https://doi.org/10.1289/EHP1090.

Review of Epidemiological Studies of Drinking-Water Turbidity in Relation to Acute Gastrointestinal Illness

PubMed Central

Gurian, Patrick L.; Robinson, Lucy F.; Rai, Arjita; Zakeri, Issa; Kondo, Michelle C.

2017-01-01

Background: Turbidity has been used as an indicator of microbiological contamination of drinking water in time-series studies attempting to discern the presence of waterborne gastrointestinal illness; however, the utility of turbidity as a proxy exposure measure has been questioned. Objectives: We conducted a review of epidemiological studies of the association between turbidity of drinking-water supplies and incidence of acute gastrointestinal illness (AGI), including a synthesis of the overall weight of evidence. Our goal was to evaluate the potential for causal inference from the studies. Methods: We identified 14 studies on the topic (distinct by region, time period and/or population). We evaluated each study with regard to modeling approaches, potential biases, and the strength of evidence. We also considered consistencies and differences in the collective results. Discussion: Positive associations between drinking-water turbidity and AGI incidence were found in different cities and time periods, and with both unfiltered and filtered supplies. There was some evidence for a stronger association at higher turbidity levels. The studies appeared to adequately adjust for confounding. There was fair consistency in the notable lags between turbidity measurement and AGI identification, which fell between 6 and 10 d in many studies. Conclusions: The observed associations suggest a detectable incidence of waterborne AGI from drinking water in the systems and time periods studied. However, some discrepant results indicate that the association may be context specific. Combining turbidity with seasonal and climatic factors, additional water quality measures, and treatment data may enhance predictive modeling in future studies. https://doi.org/10.1289/EHP1090 PMID:28886603

Does time of day influence cancer detection and recall rates in mammography?

NASA Astrophysics Data System (ADS)

Stinton, Chris; Jenkinson, David; Adekanmbi, Victor; Clarke, Aileen; Taylor-Phillips, Sian

2017-03-01

Background: The interpretation of screening mammograms is influenced by factors such as reader experience and their annual interpretative volume. There is some evidence that time of day can also have an effect, with better diagnostic accuracy for readings conducted early in the day. This is not a consistent finding, however. The aim of our study is to provide further evidence on whether there is an effect of time of day on recall- and breast cancer detection rates. Method: We analysed breast screening data from 222,577 women from the Midlands of England. Data were split into three eight hour periods: 0900-1700, 1700-0100, 0100-0900. Differences in recall- and cancer detection rates were analysed using multilevel logistic regression models. Results: Recall rates were lowest for mammograms read between the 1700-0100 time period. Cancer detection rates were lowest during the 0100-0900 time period. Conclusions: Our findings suggest that there are fluctuations in recall- and cancer detection rates over the course of the day.

The role of time perspective in smoking cessation amongst older English adults.

PubMed

Adams, Jean

2009-09-01

To study the longitudinal relationship between time perspective and smoking cessation over 4 years of follow-up among a cohort of older English adults and to determine whether the predictive utility of time perspective in smoking cessation. Analysis of data from core members of the English Longitudinal Survey of Ageing who took part in face-to-face interviews in 2002, 2004, and 2006 (n = 7,174). Time perspective was measured using a question on time period for financial planning. Smoking at baseline and quitting over follow-up was determined through self-report. At baseline, planning for longer periods was associated with lower odds of being a smoker, after controlling for age, gender, and education. Among those who were smokers at baseline, planning for longer periods at baseline was associated with increased odds of quitting over 4 years, after controlling for age, gender, and education. Including help to become more future orientated in smoking cessation interventions may increase their effectiveness. Copyright 2009 APA, all rights reserved.

Wealth and the Accounting Period in the Measurement of Means. The Measure of Poverty, Technical Paper VI.

ERIC Educational Resources Information Center

Steuerle, Eugene; McClung, Nelson

This technical study is concerned with both the statistical and policy effects of alternative definitions of poverty which result when the definition of means is altered by varying the time period (accounting period) over which income is measured or by including in the measure of means not only realized income, but also unrealized income and…

Short communication: Rumination and feeding behaviors differ between healthy and sick dairy cows during the transition period.

PubMed

Schirmann, K; Weary, D M; Heuwieser, W; Chapinal, N; Cerri, R L A; von Keyserlingk, M A G

2016-12-01

The objectives of this study were: (1) to describe the rumination and feeding behavior of freestall-housed Holstein dairy cows in the weeks around parturition, and (2) to determine the relationship between postpartum disease and precalving rumination and feeding behavior. Eighty cows were enrolled at approximately 2wk (18±7d, mean ± standard deviation) before calving. Using automatic monitoring systems, rumination and feeding behavior were recorded continuously from 10d before until 3wk after calving. Postpartum health checks were performed each day, and metritis assessment was conducted 2 times/wk. Blood β-hydroxybutyrate was measured 3 times/week, and cows with ≥1.2mmol/L during the first 14d postpartum were diagnosed as having subclinical ketosis. The final data set included 64 cows in 5 groups: healthy (n=20), metritis (n=18), subclinical ketosis (SCK; n=9), metritis+SCK (n=9), and >1 health problem and not included before (MULT, n=8). We compared rumination and feeding data between healthy cows and the 4 categories of ill animals in each of 4 periods relative to calving: precalving (d -7 to -2), period 1 (d 3 to 8 postpartum), period 2 (d 9 to 14 postpartum), and period 3 (d 15 to 20 postpartum). Cows with SCK spent less time ruminating during the precalving period. Compared with healthy cows, those with SCK and metritis+SCK had lower dry matter intake during the precalving period and continued to eat less until d 14 and d 20 postpartum, respectively. Cows with metritis and MULT cows had lower dry matter intake during the first 2wk postpartum. Precalving feeding time was lower for SCK, metritis+SCK, and MULT cows compared with healthy cows. The difference in feeding time between healthy and metritis+SCK cows had disappeared by period 2 and between all health categories except MULT by period 3. MULT cows visited the feed bins less often and were less often replaced at the feed bin throughout all 4 periods of the study. Automatic monitoring of intake and rumination showed promise for the detection of health problems after calving. We observed differences in precalving rumination and feeding behavior. Further research is necessary to better understand the onset of behavioral changes and the relationship between rumination and disease. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

36 CFR 218.10 - Objection time periods and process.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 36 Parks, Forests, and Public Property 2 2012-07-01 2012-07-01 false Objection time periods and... Objection time periods and process. (a) Time to file an objection. Written objections, including any... of objectors to ensure that their objection is received in a timely manner. (b) Computation of time...

The timing behavior of magnetar Swift J1822.3-1606: timing noise or a decreasing period derivative?

NASA Astrophysics Data System (ADS)

Tong, Hao; Xu, Ren-Xin

2013-10-01

The different timing results of the magnetar Swift J1822.3-1606 are analyzed and understood theoretically. It is noted that different timing solutions are caused not only by timing noise, but also because the period derivative is decreasing after the outburst. Both the decreasing period derivative and the large timing noise may originate from wind braking associated with the magnetar. Future timing of Swift J1822.3-1606 will help clarify whether or not its period derivative is decreasing with time.

Responses of the autonomic nervous system during periods of perceived high and low work stress in younger and older female teachers.

PubMed

Ritvanen, Tiina; Louhevaara, Veikko; Helin, Pertti; Väisänen, Sari; Hänninen, Osmo

2006-05-01

The aim of this study was to examine the response of the autonomic nervous system in younger (mean age 31 yrs, n=14) and older (mean age 54 yrs, n=14) healthy female teachers during work periods of perceived high and low stress. In the younger participants, heart rate, cortisol excretion rate and psychosomatic symptoms were significantly higher during the high work stress period. The older participants experienced no decrease in their heart rate and cortisol excretion during the low stress period and they exhibited no significant decrease in blood pressure after the work in the evening during both periods. It may be concluded that the recovery from the stress in the older teachers was insufficient particularly in view of their elevated diastolic blood pressure during the low work stress period. Ergonomic and individually tailored measures in terms of work time control, specific relaxation techniques, and a part-time retirement may improve the stress management of older teachers.

Environmental Enrichment Rescues Binocular Matching of Orientation Preference in Mice that Have a Precocious Critical Period

PubMed Central

Wang, Bor-Shuen; Feng, Liang; Liu, Mingna; Liu, Xiaorong; Cang, Jianhua

2013-01-01

SUMMARY Experience shapes neural circuits during critical periods in early life. The timing of critical periods is regulated by both genetics and the environment. Here we study the functional significance of such temporal regulations in the mouse primary visual cortex, where critical period plasticity drives binocular matching of orientation preference. We find that the binocular matching is permanently disrupted in mice that have a precocious critical period due to genetically enhanced inhibition. The disruption is specific to one type of neurons, the complex cells, which, as we reveal, normally match after the simple cells. Early environmental enrichment completely rescues the deficit by inducing histone acetylation and consequently advancing the matching process to coincide with the precocious plasticity. Our experiments thus demonstrate that the proper timing of the critical period is essential for establishing normal binocularity and the detrimental impact of its genetic misregulation can be ameliorated by environmental manipulations via epigenetic mechanisms. PMID:24012279

Agency Beliefs Over Time and Across Cultures: Free Will Beliefs Predict Higher Job Satisfaction

PubMed Central

Feldman, Gilad; Farh, Jiing-Lih; Wong, Kin Fai Ellick

2017-01-01

In three studies, we examined the relationship between free will beliefs and job satisfaction over time and across cultures. Study 1 examined 252 Taiwanese real-estate agents over a 3-months period. Study 2 examined job satisfaction for 137 American workers on an online labor market over a 6-months period. Study 3 extended to a large sample of 14,062 employees from 16 countries and examined country-level moderators. We found a consistent positive relationship between the belief in free will and job satisfaction. The relationship was above and beyond other agency constructs (Study 2), mediated by perceived autonomy (Studies 2-3), and stronger in countries with a higher national endorsement of the belief in free will (Study 3). We conclude that free-will beliefs predict outcomes over time and across cultures beyond other agency constructs. We call for more cross-cultural and longitudinal studies examining free-will beliefs as predictors of real-life outcomes. PMID:29191084

Agency Beliefs Over Time and Across Cultures: Free Will Beliefs Predict Higher Job Satisfaction.

PubMed

Feldman, Gilad; Farh, Jiing-Lih; Wong, Kin Fai Ellick

2018-03-01

In three studies, we examined the relationship between free will beliefs and job satisfaction over time and across cultures. Study 1 examined 252 Taiwanese real-estate agents over a 3-months period. Study 2 examined job satisfaction for 137 American workers on an online labor market over a 6-months period. Study 3 extended to a large sample of 14,062 employees from 16 countries and examined country-level moderators. We found a consistent positive relationship between the belief in free will and job satisfaction. The relationship was above and beyond other agency constructs (Study 2), mediated by perceived autonomy (Studies 2-3), and stronger in countries with a higher national endorsement of the belief in free will (Study 3). We conclude that free-will beliefs predict outcomes over time and across cultures beyond other agency constructs. We call for more cross-cultural and longitudinal studies examining free-will beliefs as predictors of real-life outcomes.

Bayesian dynamic modeling of time series of dengue disease case counts

PubMed Central

López-Quílez, Antonio; Torres-Prieto, Alexander

2017-01-01

The aim of this study is to model the association between weekly time series of dengue case counts and meteorological variables, in a high-incidence city of Colombia, applying Bayesian hierarchical dynamic generalized linear models over the period January 2008 to August 2015. Additionally, we evaluate the model’s short-term performance for predicting dengue cases. The methodology shows dynamic Poisson log link models including constant or time-varying coefficients for the meteorological variables. Calendar effects were modeled using constant or first- or second-order random walk time-varying coefficients. The meteorological variables were modeled using constant coefficients and first-order random walk time-varying coefficients. We applied Markov Chain Monte Carlo simulations for parameter estimation, and deviance information criterion statistic (DIC) for model selection. We assessed the short-term predictive performance of the selected final model, at several time points within the study period using the mean absolute percentage error. The results showed the best model including first-order random walk time-varying coefficients for calendar trend and first-order random walk time-varying coefficients for the meteorological variables. Besides the computational challenges, interpreting the results implies a complete analysis of the time series of dengue with respect to the parameter estimates of the meteorological effects. We found small values of the mean absolute percentage errors at one or two weeks out-of-sample predictions for most prediction points, associated with low volatility periods in the dengue counts. We discuss the advantages and limitations of the dynamic Poisson models for studying the association between time series of dengue disease and meteorological variables. The key conclusion of the study is that dynamic Poisson models account for the dynamic nature of the variables involved in the modeling of time series of dengue disease, producing useful models for decision-making in public health. PMID:28671941

Cherry blossom phenological data since the seventeenth century for Edo (Tokyo), Japan, and their application to estimation of March temperatures

NASA Astrophysics Data System (ADS)

Aono, Yasuyuki

2015-04-01

The changes in March mean temperatures in Edo (Tokyo), Japan, since the seventeenth century, were reconstructed using phenological data for the cherry blossoms of Prunus jamasakura deduced from old diaries and chronicles. The observations of the time of full blossoming and of cherry blossom viewing parties were acquired and used to construct a full-blossoming phenological data series for P. jamasakura. Phenological data from 207 of the years from 1601 to 1905 were used for this study. The reconstructed temperatures suggested the existence of two cold periods (the second half of the seventeenth century and the beginning of the nineteenth century), during which times the estimated March mean temperatures were about 4 °C and 5 °C, respectively. These two cold periods at Edo coincided with those reconstructed at Kyoto in previous studies. These cold periods coincided with two less extreme periods, the Maunder and Dalton minima, in the long-term solar variation cycle.

Sleep architecture changes during a trek from 1400 to 5000 m in the Nepal Himalaya.

PubMed

Johnson, Pamela L; Edwards, Natalie; Burgess, Keith R; Sullivan, Colin E

2010-03-01

The aim of this study was to examine sleep architecture at high altitude and its relationship to periodic breathing during incremental increases in altitude. Nineteen normal, sea level-dwelling volunteers were studied at sea level and five altitudes in the Nepal Himalaya. Morning arterial blood gases and overnight polysomnography were performed in 14 subjects at altitudes: 0, 1400, 3500, 3900, 4200 and 5000 m above sea level. Subjects became progressively more hypoxic, hypocapnic and alkalinic with increasing altitude. As expected, sleep architecture was affected by increasing altitude. While time spent in Stage 1 non-rapid eye movement sleep increased at 3500 m and higher (P < 0.001), time spent in slow-wave sleep (SWS) decreased as altitude increased. Time spent in rapid eye movement (REM) sleep was well preserved. In subjects who developed periodic breathing during sleep at one or more altitudes (16 of 19), arousals because of periodic breathing predominated, contributing to an increase in the total arousal index. However, there were no differences in sleep architecture or sleeping oxyhaemoglobin saturation between subjects who developed periodic breathing and those who did not. As altitude increased, sleep architecture became progressively more disturbed, with Stage 1 and SWS being affected from 3500 m, while REM sleep was well preserved. Periodic breathing was commonplace at all altitudes, and while associated with increases in arousal indices, did not have any apparent effect on sleep architecture.

The Press and Government Restriction: A 13-Year Update of a Cross-National Study.

ERIC Educational Resources Information Center

Weaver, David H.; Buddenbaum, Judith M.

In 1974, David H. Weaver used path analysis with data from 137 countries during four periods between 1950 and 1966 to test relationships between government control of the press and six other societal characteristics. The present study, which extended the time period of the original analysis by adding recently available data from 1979, constructed…

Publication Patterns of U.S. Academic Librarians and Libraries from 2003 to 2012

ERIC Educational Resources Information Center

Blecic, Deborah D.; Wiberley, Stephen E., Jr.; De Groote, Sandra L.; Cullars, John; Shultz, Mary; Chan, Vivian

2017-01-01

This study investigated contributions to the peer-reviewed library and information science (LIS) journal literature by U.S. academic librarian (USAL) authors over a ten-year period (2003-2012). The results were compared to those of two previous five-year studies that covered the time periods of 1993-1997 and 1998-2002 to examine longitudinal…

The life course model as a framework for post-conflict health analysis: reflections on the Gulf War critical period.

PubMed

Cange, Charles W

2016-01-01

In the Kuwait context, from January 1991 to December 1991, there were a series of chemical and psychological Gulf War-era exposures that left persistent, long-term damage. Extreme stress from a critical event speeds up the usual disease latency period, and may be part of a synergistic effect that leads to higher disease rates over a shorter period of time. I am interested in the impact of armed conflict on health outcomes over the life course in Kuwait, and particularly the pathways through which armed conflict causes changes in health on a population level. In this paper, I propose a culturally sensitive, post-conflict socio-ecological model that informs a three-pronged health study. I propose a macro-micro mix that includes an ecological study, a case-control study and a qualitative study to investigate Kuwait's post-conflict health concerns. Thus, I revise the concept of 'post-conflict health' as a trajectory that is mediated through different, complex social levels and develops over time during the latency period. The main advantage of a macro-micro mix approach for post-conflict health is that it contextualizes the Gulf War as an environmental health issue.

Thermosolutal convection during directional solidification. II - Flow transitions

NASA Technical Reports Server (NTRS)

Mcfadden, G. B.; Coriell, S. R.

1987-01-01

The influence of thermosolutal convection on solute segregation in crystals grown by vertical directional solidification of binary metallic alloys or semiconductors is studied. Finite differences are used in a two-dimensional time-dependent model which assumes a planar crystal-melt interface to obtain numerical results. It is assumed that the configuration is periodic in the horizontal direction. Consideration is given to the possibility of multiple flow states sharing the same period. The results are represented in bifurcation diagrams of the nonlinear states associated with the critical points of linear theory. Variations of the solutal Rayleigh number can lead to the occurrence of multiple steady states, time-periodic states, and quasi-periodic states. This case is compared to that of thermosolutal convection with linear vertical gradients and stress-free boundaries.

Timing Effects on Divorce: 20th Century Experience in the United States

ERIC Educational Resources Information Center

Schoen, Robert; Canudas-Romo, Vladimir

2006-01-01

Period divorce measures can misrepresent the underlying behavior of birth cohorts as changes in cohort timing produce changes in period probabilities of divorce. Building on methods used to adjust period fertility and marriage measures, we adjust U.S. period divorce rates for timing effects, calculating a timing index for every year between 1910…

13 CFR 134.103 - Rules applicable to time periods provided in this part.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Rules applicable to time periods provided in this part. (a) The day from which the time period is... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Rules applicable to time periods provided in this part. 134.103 Section 134.103 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION...

A Comparative Study of Electric Load Curve Changes in an Urban Low-Voltage Substation in Spain during the Economic Crisis (2008–2013)

PubMed Central

Lara-Santillán, Pedro M.; Mendoza-Villena, Montserrat; Fernández-Jiménez, L. Alfredo; Mañana-Canteli, Mario

2014-01-01

This paper presents a comparative study of the electricity consumption (EC) in an urban low-voltage substation before and during the economic crisis (2008–2013). This low-voltage substation supplies electric power to near 400 users. The EC was measured for an 11-year period (2002–2012) with a sampling time of 1 minute. The study described in the paper consists of detecting the changes produced in the load curves of this substation along the time due to changes in the behaviour of consumers. The EC was compared using representative curves per time period (precrisis and crisis). These representative curves were obtained after a computational process, which was based on a search for days with similar curves to the curve of a determined (base) date. This similitude was assessed by the proximity on the calendar, day of the week, daylight time, and outdoor temperature. The last selection parameter was the error between the nearest neighbour curves and the base date curve. The obtained representative curves were linearized to determine changes in their structure (maximum and minimum consumption values, duration of the daily time slot, etc.). The results primarily indicate an increase in the EC in the night slot during the summer months in the crisis period. PMID:24895677

Comparison of detrending methods for fluctuation analysis in hydrology

NASA Astrophysics Data System (ADS)

Zhang, Qiang; Zhou, Yu; Singh, Vijay P.; Chen, Yongqin David

2011-03-01

SummaryTrends within a hydrologic time series can significantly influence the scaling results of fluctuation analysis, such as rescaled range (RS) analysis and (multifractal) detrended fluctuation analysis (MF-DFA). Therefore, removal of trends is important in the study of scaling properties of the time series. In this study, three detrending methods, including adaptive detrending algorithm (ADA), Fourier-based method, and average removing technique, were evaluated by analyzing numerically generated series and observed streamflow series with obvious relative regular periodic trend. Results indicated that: (1) the Fourier-based detrending method and ADA were similar in detrending practices, and given proper parameters, these two methods can produce similarly satisfactory results; (2) detrended series by Fourier-based detrending method and ADA lose the fluctuation information at larger time scales, and the location of crossover points is heavily impacted by the chosen parameters of these two methods; and (3) the average removing method has an advantage over the other two methods, i.e., the fluctuation information at larger time scales is kept well-an indication of relatively reliable performance in detrending. In addition, the average removing method performed reasonably well in detrending a time series with regular periods or trends. In this sense, the average removing method should be preferred in the study of scaling properties of the hydrometeorolgical series with relative regular periodic trend using MF-DFA.

Interventions to reduce postpartum stress in first-time mothers: a randomized-controlled trial.

PubMed

Osman, Hibah; Saliba, Matilda; Chaaya, Monique; Naasan, Georges

2014-10-15

The postpartum period can be a challenging time particularly for first-time mothers. This study aimed to assess two different interventions designed to reduce stress in the postpartum among first-time mothers. Healthy first-time mothers with healthy newborns were recruited from hospitals in Beirut, Lebanon after delivery. The two interventions were a 20-minute film addressing common stressors in the postpartum period and a 24-hour telephone support hotline. Participants were randomized to one of four study arms to receive either the postpartum support film, the hotline service, both interventions, or a music CD (control). Participants were interviewed at eight to twelve weeks postpartum for assessment of levels of stress as measured by the Cohen Perceived Stress Scale (PSS-10). Of the 632 eligible women, 552 (88%) agreed to participate in the study. Of those, 452 (82%) completed the study. Mean PSS-10 scores of mothers who received the film alone (15.76) or the film with the hotline service (15.86) were significantly lower than that of the control group (18.93) (p-value <0.01). Among mothers who received the hotline service alone mean PSS-10 score (16.98) was also significantly lower than that of the control group (p-value <0.05). Both our postpartum support film and the 24-hour telephone hotline service reduced stress in the postpartum period in first-time mothers. These simple interventions can be easily implemented and could have an important impact on the mental wellbeing of new mothers. The trial was registered with clinicaltrials.gov (identifier # NCT00857051) on March 5, 2009.

Introducing an Instrument to Assess Time Orientation and Time Relation in Adolescents

ERIC Educational Resources Information Center

Mello, Zena R.; Finan, Laura J.; Worrell, Frank C.

2013-01-01

We report on two studies that examine new instruments that assess time orientation and time relation in adolescents. These concepts refer to how individuals think about the past, the present, and the future, with time orientation defined as the emphasis one gives toward each time period and time relation defined as the degree one perceives that…

Time course of blood pressure changes immediately after maximal exercise.

PubMed

Nakahara, H; Miyamoto, T; Nakanishi, Y; Kinoshita, H

2006-12-01

The aim of this study was to investigate the effect of exhaustive exercise on the time course of arterial blood pressure (BP) and heart rate (HR) during upright resting (inactive) and loadless pedaling (active) recovery from a bicycle exercise to exhaustion. The subjects were 11 healthy normotensive males. Systolic, diastolic and mean BP, and HR were recorded every 20 s for the initial 6 min of the recovery period. The time course of all BP measures during inactive and active recovery was characterized by a marked and sudden drop during the initial 20-s period, followed by a quick rise. This was followed by a gradual decline till the end of the recovery period. The time course of HR recovery, on the other hand, exhibited a smooth decline without the initial drop. With active recovery, the initial drop of diastolic and mean BP was less than the inactive recovery. After the 20 s period, the diastolic BP and HR were kept slightly higher with the active recovery than the inactive recovery. A sudden drop of the BP occurred at the initial recovery period of postcycle exercise to exhaustion though HR did not show such a change. The initial BP drop could be attenuated by the actively pedaling the cycle without load.

Direct matrix-assisted laser desorption ionization time-of-flight mass spectrometry improves appropriateness of antibiotic treatment of bacteremia.

PubMed

Vlek, Anne L M; Bonten, Marc J M; Boel, C H Edwin

2012-01-01

Matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) allows the identification of microorganisms directly from positive blood culture broths. Use of the MALDI-TOF MS for rapid identification of microorganisms from blood culture broths can reduce the turnaround time to identification and may lead to earlier appropriate treatment of bacteremia. During February and April 2010, direct MALDI-TOF MS was routinely performed on all positive blood cultures. During December 2009 and March 2010 no direct MALDI-TOF MS was used. Information on antibiotic therapy was collected from the hospital and intensive care units' information systems from all positive blood cultures during the study period. In total, 253 episodes of bacteremia were included of which 89 during the intervention period and 164 during the control period. Direct performance of MALDI-TOF MS on positive blood culture broths reduced the time till species identification by 28.8-h and was associated with an 11.3% increase in the proportion of patients receiving appropriate antibiotic treatment 24 hours after blood culture positivity (64.0% in the control period versus 75.3% in the intervention period (p0.01)). Routine implementation of this technique increased the proportion of patients on adequate antimicrobial treatment within 24 hours.

Patterns of antimicrobial resistance in Streptococcus suis isolates from pigs with or without streptococcal disease in England between 2009 and 2014.

PubMed

Hernandez-Garcia, Juan; Wang, Jinhong; Restif, Olivier; Holmes, Mark A; Mather, Alison E; Weinert, Lucy A; Wileman, Thomas M; Thomson, Jill R; Langford, Paul R; Wren, Brendan W; Rycroft, Andrew; Maskell, Duncan J; Tucker, Alexander W

2017-08-01

Antimicrobial resistance in Streptococcus suis, a global zoonotic pathogen of pigs, has been mostly studied only in diseased animals using surveys that have not evaluated changes over time. We compared patterns of resistance between S. suis isolates from clinical cases of disease (CC) and non-clinical case (NCC) pigs in England, collected over two discrete periods, 2009-2011 and 2013-2014. Minimum inhibitory concentrations (MIC) of 17 antimicrobials (nine classes) were determined on 405 S. suis isolates categorised by sampling period and disease association to assess changes in resistance over time and association with disease. First, isolates were characterized as resistant or susceptible using published clinical breakpoints. Second, epidemiological cut-offs (ECOFF) were derived from MIC values, and isolates classified as wild type (WT) below the ECOFF and non-wild type (NWT) above the ECOFF. Finally, isolate subsets were analysed for shifts in MIC distribution. NCC isolates were more resistant than CC isolates to cephalosporins, penams, pleuromutilins, potentiated sulphonamides and tetracyclines in both study periods. Resistance levels among CC isolates increased in 2013-2014 relative to 2009-2011 for antimicrobials including aminoglycosides, cephalosporins, fluoroquinolones, pleuromutilins, potentiated sulphonamides and tetracyclines. The prevalence of isolates categorised as NWT for five or more classes of antimicrobials was greater among NCC than CC isolates for both time periods, and increased with time. This study used standardised methods to identify significant shifts in antimicrobial resistance phenotypes of S. suis isolated from pigs in England, not only over time but also between isolates from known clinical cases or disease-free pigs. Copyright © 2017. Published by Elsevier B.V.

The Temporal and Spatial Variability of the Confined Aquifer Head and Storage Properties in the San Luis Valley, Colorado Inferred From Multiple InSAR Missions

NASA Astrophysics Data System (ADS)

Chen, Jingyi; Knight, Rosemary; Zebker, Howard A.

2017-11-01

Interferometric Synthetic Aperture Radar (InSAR) data from multiple satellite missions were combined to study the temporal and spatial variability of head and storage properties in a confined aquifer system on a decadal time scale. The area of study was a 4,500 km2 agricultural basin in the San Luis Valley (SLV), Colorado. We had available previous analyses of C-band ERS-1/2 data from June 1992 to November 2000, and L-band ALOS PALSAR data from October 2009 to March 2011. We used C-band Envisat data to fill in the time period from November 2006 to July 2010. In processing the Envisat data, we successfully employed a phase interpolation between persistent scatterer pixels to reduce the impact of vegetation decorrelation, which can significantly reduce the quality of C-band InSAR data over agricultural basins. In comparing the results from the L-band ALOS data and C-band Envisat data in a 10 month overlapping time period, we found that the shorter wavelength of C-band InSAR allowed us to preserve small deformation signals that were not detectable using L-band ALOS data. A significant result was the finding that the elastic storage properties of the SLV confined aquifer system remained stable over the 20 year time period and vary slowly in space, allowing us to combine InSAR data acquired from multiple missions to fill the temporal and spatial gaps in well data. The InSAR estimated head levels were validated with well measurements, which indicate little permanent water-storage loss over the study time period in the SLV.

Shear-induced chaos

NASA Astrophysics Data System (ADS)

Lin, Kevin K.; Young, Lai-Sang

2008-05-01

Guided by a geometric understanding developed in earlier works of Wang and Young, we carry out numerical studies of shear-induced chaos in several parallel but different situations. The settings considered include periodic kicking of limit cycles, random kicks at Poisson times and continuous-time driving by white noise. The forcing of a quasi-periodic model describing two coupled oscillators is also investigated. In all cases, positive Lyapunov exponents are found in suitable parameter ranges when the forcing is suitably directed.

Wind Observations of Anomalous Cosmic Rays from Solar Minimum to Maximum

NASA Technical Reports Server (NTRS)

Reames, D. V.; McDonald, F. B.

2003-01-01

We report the first observation near Earth of the time behavior of anomalous cosmic-ray N, O, and Ne ions through the period surrounding the maximum of the solar cycle. These observations were made by the Wind spacecraft during the 1995-2002 period spanning times from solar minimum through solar maximum. Comparison of anomalous and galactic cosmic rays provides a powerful tool for the study of the physics of solar modulation throughout the solar cycle.

Short-time Lyapunov exponent analysis and the transition to chaos in Taylor-Couette flow

NASA Technical Reports Server (NTRS)

Vastano, John A.; Moser, Robert D.

1991-01-01

The physical mechanism driving the weakly chaotic Taylor-Couette flow is investigated using the short-time Liapunov exponent analysis. In this procedure, the transition from quasi-periodicity to chaos is studied using direct numerical 3D simulations of axially periodic Taylor-Couette flow, and a partial Liapunov exponent spectrum for the flow is computed by simultaneously advancing the full solution and a set of perturbations. It is shown that the short-time Liapunov exponent analysis yields more information on the exponents and dimension than that obtained from the common Liapunov exponent calculations. Results show that the chaotic state studied here is caused by a Kelvin-Helmholtz-type instability of the outflow boundary jet of Taylor vortices.

LeRoy Doggett and Daylight Saving Time: A Reminiscence

NASA Astrophysics Data System (ADS)

Bartky, I. R.

1997-12-01

Daylight Saving Time (DST) has been a concern of Congress ever since its adoption in 1918. Yet, not until 1976 did Members of Congress have astronomical, geographic and demographic information in terms of the country's Standard Time zones. This information and various impact analyses were developed by the National Bureau of Standards (NBS) at the request of the House of Representatives, which was reviewing the effects of a two-year, DST experiment on the American public. The displays in the study gave legislators a way to consider alternate observance periods in a systematic manner. The leader of the DST study team will detail LeRoy Doggett's involvement during the hectic, three-month analysis period that culminated with NBS officials testifying before Congress.

Influencing Preschoolers' Free-Play Activity Preferences: An Evaluation of Satiation and Embedded Reinforcement

PubMed Central

Hanley, Gregory P; Tiger, Jeffrey H; Ingvarsson, Einar T; Cammilleri, Anthony P

2009-01-01

The present study evaluated the effects of classwide satiation and embedded reinforcement procedures on preschoolers' activity preferences during scheduled free-play periods. The goal of the study was to increase time allocation to originally nonpreferred, but important, activities (instructional zone, library, and science) while continuing to provide access to all free-play activities. The satiation intervention applied to preferred activities resulted in increased time allocation to the instructional and science activities, the customized embedded reinforcement interventions resulted in increased time allocation to all three target activities, and high levels of attendance to the instructional and library activities were maintained during follow-up observations. Implications for the design of preschool free-play periods are discussed. PMID:19721728

Prefrontal activity during response inhibition decreases over time in the postpartum period.

PubMed

Bannbers, Elin; Gingnell, Malin; Engman, Jonas; Morell, Arvid; Sylvén, Sara; Skalkidou, Alkistis; Kask, Kristiina; Bäckström, Torbjörn; Wikström, Johan; Poromaa, Inger Sundström

2013-03-15

The postpartum period is characterized by complex hormonal changes, but human imaging studies in the postpartum period have thus far predominantly focused on the neural correlates of maternal behavior or postpartum depression, whereas longitudinal studies on neural correlates of cognitive function across the postpartum period in healthy women are lacking. The aim of this study was to longitudinally examine response inhibition, as a measure of executive function, during the postpartum period and its neural correlates in healthy postpartum women and non-postpartum controls. Thirteen healthy postpartum women underwent event-related functional magnetic resonance imaging while performing a Go/NoGo task. The first assessment was made within 48 h of delivery, and the second at 4-7 weeks postpartum. In addition, 13 healthy women examined twice during the menstrual cycle were included as non-postpartum controls. In postpartum women region of interest analyses revealed task-related decreased activations in the right inferior frontal gyrus, right anterior cingulate, and bilateral precentral gyri at the late postpartum assessment. Generally, postpartum women displayed lower activity during response inhibition in the bilateral inferior frontal gyri and precentral gyri compared to non-postpartum controls. No differences in performance on the Go/NoGo task were found between time-points or between groups. In conclusion, this study has discovered that brain activity in prefrontal areas during a response inhibition task decreases throughout the course of the first postpartum weeks and is lower than in non-postpartum controls. Further studies on the normal adaptive brain activity changes that occur during the postpartum period are warranted. Copyright © 2012 Elsevier B.V. All rights reserved.

Sequential recruitment of study participants may inflate genetic heritability estimates.

PubMed

Noce, Damia; Gögele, Martin; Schwienbacher, Christine; Caprioli, Giulia; De Grandi, Alessandro; Foco, Luisa; Platzgummer, Stefan; Pramstaller, Peter P; Pattaro, Cristian

2017-06-01

After the success of genome-wide association studies to uncover complex trait loci, attempts to explain the remaining genetic heritability (h 2 ) are mainly focused on unraveling rare variant associations and gene-gene or gene-environment interactions. Little attention is paid to the possibility that h 2 estimates are inflated as a consequence of the epidemiological study design. We studied the time series of 54 biochemical traits in 4373 individuals from the Cooperative Health Research In South Tyrol (CHRIS) study, a pedigree-based study enrolling ten participants/day over several years, with close relatives preferentially invited within the same day. We observed distributional changes of measured traits over time. We hypothesized that the combination of such changes with the pedigree structure might generate a shared-environment component with consequent h 2 inflation. We performed variance components (VC) h 2 estimation for all traits after accounting for the enrollment period in a linear mixed model (two-stage approach). Accounting for the enrollment period caused a median h 2 reduction of 4%. For 9 traits, the reduction was of >20%. Results were confirmed by a Bayesian Markov chain Monte Carlo analysis with all VCs included at the same time (one-stage approach). The electrolytes were the traits most affected by the enrollment period. The h 2 inflation was independent of the h 2 magnitude, laboratory protocol changes, and length of the enrollment period. The enrollment process may induce shared-environment effects even under very stringent and standardized operating procedures, causing h 2 inflation. Including the day of participation as a random effect is a sensitive way to avoid overestimation.

Operational validation of a multi-period and multi-criteria model conditioning approach for the prediction of rainfall-runoff processes in small forest catchments

NASA Astrophysics Data System (ADS)

Choi, H.; Kim, S.

2012-12-01

Most of hydrologic models have generally been used to describe and represent the spatio-temporal variability of hydrological processes in the watershed scale. Though it is an obvious fact that hydrological responses have the time varying nature, optimal values of model parameters were normally considered as time invariants or constants in most cases. The recent paper of Choi and Beven (2007) presents a multi-period and multi-criteria model conditioning approach. The approach is based on the equifinality thesis within the Generalised Likelihood Uncertainty Estimation (GLUE) framework. In their application, the behavioural TOPMODEL parameter sets are determined by several performance measures for global (annual) and short (30-days) periods, clustered using a Fuzzy C-means algorithm, into 15 types representing different hydrological conditions. Their study shows a good performance on the calibration of a rainfall-runoff model in a forest catchment, and also gives strong indications that it is uncommon to find model realizations that were behavioural over all multi-periods and all performance measures, and multi-period model conditioning approach may become new effective tool for predictions of hydrological processes in ungauged catchments. This study is a follow-up study on the Choi and Beven's (2007) model conditioning approach to test how the approach is effective for the prediction of rainfall-runoff responses in ungauged catchments. To achieve this purpose, 6 small forest catchments are selected among the several hydrological experimental catchments operated by Korea Forest Research Institute. In each catchment, long-term hydrological time series data varying from 10 to 30 years were available. The areas of the selected catchments range from 13.6 to 37.8 ha, and all areas are covered by coniferous or broad-leaves forests. The selected catchments locate in the southern coastal area to the northern part of South Korea. The bed rocks are Granite gneiss, Granite or Limestone. The study is progressed based on the followings. Firstly, hydrological time series of each catchment are sampled and clustered into multi-period having distinctly different temporal characteristics, and secondly, behavioural parameter distributions are determined in each multi-period based on the specification of multi-criteria model performance measures. Finally, behavioural parameter sets of each multi-period of single catchment are applied on the corresponding period of other catchments, and the cross-validations are conducted in this manner for all catchments The multi-period model conditioning approach is clearly effective to reduce the width of prediction limits, giving better model performance against the temporal variability of hydrological characteristics, and has enough potential to be the effective prediction tool for ungauged catchments. However, more advanced and continuous studies are needed to expand the application of this approach in prediction of hydrological responses in ungauged catchments,

Self-affinity in the dengue fever time series

NASA Astrophysics Data System (ADS)

Azevedo, S. M.; Saba, H.; Miranda, J. G. V.; Filho, A. S. Nascimento; Moret, M. A.

2016-06-01

Dengue is a complex public health problem that is common in tropical and subtropical regions. This disease has risen substantially in the last three decades, and the physical symptoms depict the self-affine behavior of the occurrences of reported dengue cases in Bahia, Brazil. This study uses detrended fluctuation analysis (DFA) to verify the scale behavior in a time series of dengue cases and to evaluate the long-range correlations that are characterized by the power law α exponent for different cities in Bahia, Brazil. The scaling exponent (α) presents different long-range correlations, i.e. uncorrelated, anti-persistent, persistent and diffusive behaviors. The long-range correlations highlight the complex behavior of the time series of this disease. The findings show that there are two distinct types of scale behavior. In the first behavior, the time series presents a persistent α exponent for a one-month period. For large periods, the time series signal approaches subdiffusive behavior. The hypothesis of the long-range correlations in the time series of the occurrences of reported dengue cases was validated. The observed self-affinity is useful as a forecasting tool for future periods through extrapolation of the α exponent behavior. This complex system has a higher predictability in a relatively short time (approximately one month), and it suggests a new tool in epidemiological control strategies. However, predictions for large periods using DFA are hidden by the subdiffusive behavior.

Statistical Significance of Periodicity and Log-Periodicity with Heavy-Tailed Correlated Noise

NASA Astrophysics Data System (ADS)

Zhou, Wei-Xing; Sornette, Didier

We estimate the probability that random noise, of several plausible standard distributions, creates a false alarm that a periodicity (or log-periodicity) is found in a time series. The solution of this problem is already known for independent Gaussian distributed noise. We investigate more general situations with non-Gaussian correlated noises and present synthetic tests on the detectability and statistical significance of periodic components. A periodic component of a time series is usually detected by some sort of Fourier analysis. Here, we use the Lomb periodogram analysis, which is suitable and outperforms Fourier transforms for unevenly sampled time series. We examine the false-alarm probability of the largest spectral peak of the Lomb periodogram in the presence of power-law distributed noises, of short-range and of long-range fractional-Gaussian noises. Increasing heavy-tailness (respectively correlations describing persistence) tends to decrease (respectively increase) the false-alarm probability of finding a large spurious Lomb peak. Increasing anti-persistence tends to decrease the false-alarm probability. We also study the interplay between heavy-tailness and long-range correlations. In order to fully determine if a Lomb peak signals a genuine rather than a spurious periodicity, one should in principle characterize the Lomb peak height, its width and its relations to other peaks in the complete spectrum. As a step towards this full characterization, we construct the joint-distribution of the frequency position (relative to other peaks) and of the height of the highest peak of the power spectrum. We also provide the distributions of the ratio of the highest Lomb peak to the second highest one. Using the insight obtained by the present statistical study, we re-examine previously reported claims of ``log-periodicity'' and find that the credibility for log-periodicity in 2D-freely decaying turbulence is weakened while it is strengthened for fracture, for the ion-signature prior to the Kobe earthquake and for financial markets.

Daily computer usage correlated with undergraduate students' musculoskeletal symptoms.

PubMed

Chang, Che-Hsu Joe; Amick, Benjamin C; Menendez, Cammie Chaumont; Katz, Jeffrey N; Johnson, Peter W; Robertson, Michelle; Dennerlein, Jack Tigh

2007-06-01

A pilot prospective study was performed to examine the relationships between daily computer usage time and musculoskeletal symptoms on undergraduate students. For three separate 1-week study periods distributed over a semester, 27 students reported body part-specific musculoskeletal symptoms three to five times daily. Daily computer usage time for the 24-hr period preceding each symptom report was calculated from computer input device activities measured directly by software loaded on each participant's primary computer. General Estimating Equation models tested the relationships between daily computer usage and symptom reporting. Daily computer usage longer than 3 hr was significantly associated with an odds ratio 1.50 (1.01-2.25) of reporting symptoms. Odds of reporting symptoms also increased with quartiles of daily exposure. These data suggest a potential dose-response relationship between daily computer usage time and musculoskeletal symptoms.

Relationship between Alcohol Purchasing Time and Alcohol Use Disorder in South Korea

PubMed Central

Amista, Narcie Faith; Chun, Sungsoo; Yun, Mieun

2017-01-01

Objectives Currently, time of alcohol purchase is not part of the policies to regulate alcohol consumption in South Korea. This study was conducted to determine the relationship between alcohol purchasing time and alcohol use disorder. Methods The survey for this study was conducted in geographically diverse regions of South Korea in 2012. Respondents’ purchasing behaviors for both on-licensed (i.e., allows for consumption within the premises) and off-licensed (i.e., where alcohol is consumed off the premises) outlets and time of alcohol consumption were collected. Alcohol consumption patterns were examined using the Rapid Alcohol Problem Screen 4 (RAPS4). Data were also analyzed by age, gender and purchasing time. Results Results showed that among the off-licensed premises, supermarkets appear to be the most popular venue while for on-licensed premises; alcohol was generally consumed inside hotels/pubs regardless of age and gender of the purchaser. Purchasing of alcohol was highest during the day and early evening period (9:00 a.m. to 9:59 p.m.). Females are most likely to abuse alcohol than males during the early morning period and is that period after 12:00 midnight. Conclusion Analysis suggests that the survey instrument used in the International Alcohol Control Study is being used to collect data on alcohol purchasing time consumption; therefore, the potential is there to provide accurate results to contribute appropriate policy responses to reduce alcohol related-harm. PMID:29354399

A pilot study characterizing real time exposures to particulate matter and carbon monoxide from cookstove related woodsmoke in rural Peru

NASA Astrophysics Data System (ADS)

Commodore, Adwoa A.; Hartinger, Stella M.; Lanata, Claudio F.; Mäusezahl, Daniel; Gil, Ana I.; Hall, Daniel B.; Aguilar-Villalobos, Manuel; Naeher, Luke P.

2013-11-01

Nearly half of the world's population is exposed to household air pollution (HAP) due to long hours spent in close proximity to unvented cooking fires. We aimed to use PM2.5 and CO measurements to characterize exposure to cookstove generated woodsmoke in real time among control (n = 10) and intervention (n = 9) households in San Marcos, Cajamarca Region, Peru. Real time personal particulate matter with an aerodynamic diameter ≤2.5 μm (PM2.5), and personal and kitchen carbon monoxide (CO) samples were taken. Control households used a number of stoves including open fire and chimney stoves while intervention households used study-promoted chimney stoves. Measurements were categorized into lunch (9 am-1 pm) and dinner (3 pm-7 pm) periods, where applicable, to adjust for a wide range of sampling periods (2.8-13.1 h). During the 4-h time periods, mean personal PM2.5 exposures were correlated with personal CO exposures during lunch (r = 0.67 p = 0.024 n = 11) and dinner (r = 0.72 p = 0.0011 n = 17) in all study households. Personal PM2.5 exposures and kitchen CO concentrations were also correlated during lunch (r = 0.76 p = 0.018 n = 9) and dinner (r = 0.60 p = 0.018 n = 15). CO may be a useful indicator of PM during 4-h time scales measured in real time, particularly during high woodsmoke exposures, particularly during residential biomass cooking.

Amplitude Variations in Pulsating Red Giants. II. Some Systematics

NASA Astrophysics Data System (ADS)

Percy, J. R.; Laing, J.

2017-12-01

In order to extend our previous studies of the unexplained phenomenon of cyclic amplitude variations in pulsating red giants, we have used the AAVSO time-series analysis package vstar to analyze long-term AAVSO visual observations of 50 such stars, mostly Mira stars. The relative amount of the variation, typically a factor of 1.5, and the time scale of the variation, typically 20-35 pulsation periods, are not significantly different in longer-period, shorter-period, and carbon stars in our sample, and they also occur in stars whose period is changing secularly, perhaps due to a thermal pulse. The time scale of the variations is similar to that in smaller-amplitude SR variables, but the relative amount of the variation appears to be larger in smaller-amplitude stars, and is therefore more conspicuous. The cause of the amplitude variations remains unclear, though they may be due to rotational modulation of a star whose pulsating surface is dominated by the effects of large convective cells.

Contribution to harmonic balance calculations of self-sustained periodic oscillations with focus on single-reed instruments.

PubMed

Farner, Snorre; Vergez, Christophe; Kergomard, Jean; Lizée, Aude

2006-03-01

The harmonic balance method (HBM) was originally developed for finding periodic solutions of electronical and mechanical systems under a periodic force, but has been adapted to self-sustained musical instruments. Unlike time-domain methods, this frequency-domain method does not capture transients and so is not adapted for sound synthesis. However, its independence of time makes it very useful for studying any periodic solution, whether stable or unstable, without care of particular initial conditions in time. A computer program for solving general problems involving nonlinearly coupled exciter and resonator, HARMBAL, has been developed based on the HBM. The method as well as convergence improvements and continuation facilities are thoroughly presented and discussed in the present paper. Applications of the method are demonstrated, especially on problems with severe difficulties of convergence: the Helmholtz motion (square signals) of single-reed instruments when no losses are taken into account, the reed being modeled as a simple spring.

Improving Emergency Department radiology transportation time: a successful implementation of lean methodology.

PubMed

Hitti, Eveline A; El-Eid, Ghada R; Tamim, Hani; Saleh, Rana; Saliba, Miriam; Naffaa, Lena

2017-09-05

Emergency Department overcrowding has become a global problem and a growing safety and quality concern. Radiology and laboratory turnaround time, ED boarding and increased ED visits are some of the factors that contribute to ED overcrowding. Lean methods have been used in the ED to address multiple flow challenges from improving door-to-doctor time to reducing length of stay. The objective of this study is to determine the effectiveness of using Lean management methods on improving Emergency Department transportation times for plain radiography. We performed a before and after study at an academic urban Emergency Department with 49,000 annual visits after implementing a Lean driven intervention. The primary outcome was mean radiology transportation turnaround time (TAT). Secondary outcomes included overall study turnaround time from order processing to preliminary report time as well as ED length of stay. All ED patients undergoing plain radiography 6 months pre-intervention were compared to all ED patients undergoing plain radiography 6 months post-intervention after a 1 month washout period. Post intervention there was a statistically significant decrease in the mean transportation TAT (mean ± SD: 9.87 min ± 15.05 versus 22.89 min ± 22.05, respectively, p-value <0.0001). In addition, it was found that 71.6% of patients in the post-intervention had transportation TAT ≤ 10 min, as compared to 32.3% in the pre-intervention period, p-value <0.0001, with narrower interquartile ranges in the post-intervention period. Similarly, the "study processing to preliminary report time" and the length of stay were lower in the post-intervention as compared to the pre-intervention, (52.50 min ± 35.43 versus 54.04 min ± 34.72, p-value = 0.02 and 3.65 h ± 5.17 versus 4.57 h ± 10.43, p < 0.0001, respectively), in spite of an increase in the time it took to elease a preliminary report in the post-intervention period. Using Lean change management techniques can be effective in reducing transportation time to plain radiography in the Emergency Department as well as improving process reliability.

Applying Sparse Machine Learning Methods to Twitter: Analysis of the 2012 Change in Pap Smear Guidelines. A Sequential Mixed-Methods Study.

PubMed

Lyles, Courtney Rees; Godbehere, Andrew; Le, Gem; El Ghaoui, Laurent; Sarkar, Urmimala

2016-06-10

It is difficult to synthesize the vast amount of textual data available from social media websites. Capturing real-world discussions via social media could provide insights into individuals' opinions and the decision-making process. We conducted a sequential mixed methods study to determine the utility of sparse machine learning techniques in summarizing Twitter dialogues. We chose a narrowly defined topic for this approach: cervical cancer discussions over a 6-month time period surrounding a change in Pap smear screening guidelines. We applied statistical methodologies, known as sparse machine learning algorithms, to summarize Twitter messages about cervical cancer before and after the 2012 change in Pap smear screening guidelines by the US Preventive Services Task Force (USPSTF). All messages containing the search terms "cervical cancer," "Pap smear," and "Pap test" were analyzed during: (1) January 1-March 13, 2012, and (2) March 14-June 30, 2012. Topic modeling was used to discern the most common topics from each time period, and determine the singular value criterion for each topic. The results were then qualitatively coded from top 10 relevant topics to determine the efficiency of clustering method in grouping distinct ideas, and how the discussion differed before vs. after the change in guidelines . This machine learning method was effective in grouping the relevant discussion topics about cervical cancer during the respective time periods (~20% overall irrelevant content in both time periods). Qualitative analysis determined that a significant portion of the top discussion topics in the second time period directly reflected the USPSTF guideline change (eg, "New Screening Guidelines for Cervical Cancer"), and many topics in both time periods were addressing basic screening promotion and education (eg, "It is Cervical Cancer Awareness Month! Click the link to see where you can receive a free or low cost Pap test.") It was demonstrated that machine learning tools can be useful in cervical cancer prevention and screening discussions on Twitter. This method allowed us to prove that there is publicly available significant information about cervical cancer screening on social media sites. Moreover, we observed a direct impact of the guideline change within the Twitter messages.

[Medical Relief Response by Miyako Public Health Center after the Great East Japan Earthquake and Tsunami, 2011].

PubMed

Yanagihara, Hiroki

2016-01-01

To improve disaster preparedness, we investigated the response of medical relief activities managed by Iwate Prefectural Miyako Public Health Center during the post-acute phase of the Great East Japan Earthquake and Tsunami on March 11, 2011. The study divided the post-disaster period into three approximate time segments: Period I (time of disaster through late March), Period II (mid-April), and Period III (end of May in Miyako City, early July in Yamada Town). We reviewed records on medical relief activities conducted by medical assistance teams (MATs) in Miyako City and Yamada Town. Miyako Public Health Center had organized a meeting to coordinate medical relief activities from Period I to Period III. According to demand for medical services and recovery from the local medical institutions (LMIs) in the affected area, MATs were deployed and active on evacuation centers in each area assigned. The number of patients examined by MATs in Miyako rose to approximately 250 people per day in Period I and decreased to 100 in Period III. However, in Yamada, the number surged to 700 in Period I, fell to 100 in Period II, and decreased to 50 in Period III. This difference could be partly explained as follows. In Miyako, most evacuees had consulted LMIs which restarted medical services after disaster, and the number of LMIs restarted had already reached 29 (94% of the whole) in Period I. In Yamada, most evacuees who had consulted MATs in Period I had almost moved to LMIs restarted in Period II. During the same time, a division of roles and coordination on medical services provision was conducted, such as MATs mainly in charge of primary emergency triage, in response to the number of LMIs restarted which reached 1 (20%) in Period I and 3 (60%) in Period II. Following Period III, more than 80% of patients in Miyako had been a slight illness, such as need for health guidance, and the number of people who underwent emergency medical transport reached pre-disaster levels in both locations. These results suggest that demand for medical services of evacuees declined to a stable level in an early stage of Period III. Using the above findings, one might justify supporting local medical institutions' recovery earlier. Then, medical relief activities might be finished properly. This study shows useful perspectives in the response of medical relief activities during post-acute phase after disaster and the importance of establishing systems for information management that apply these perspectives.

Post-exercise heart rate variability recovery: a time-frequency analysis.

PubMed

Peçanha, Tiago; de Paula-Ribeiro, Marcelle; Nasario-Junior, Olivassé; de Lima, Jorge Roberto Perrout

2013-12-01

Most studies investigating the effects of non-pharmacological interventions, such as physical training (PT), on cardiac autonomic control, assessed the HRV only in resting conditions. Recently, a new time-frequency mathematical approach based on the short-time Fourier transform (STFT) method has been validated for the assessment of HRV in non-stationary conditions such as the immediate post-exercise period. The aim of this study was to evaluate the effects of the PT on post-exercise cardiac autonomic control using the time-frequency STFT analysis of the HRV. Twenty-one healthy male volunteers participated in this study. The subjects were initially evaluated for their physical exercise/sport practice and allocated to groups of low physical training ((Low)PT, n = 13) or high physical training (H(igh)PT, n = 8). The post-exercise HRV was assessed by the STFT method, which provides the analysis of dynamic changes in the power of the low- and high-frequency spectral components (LF and HF, respectively) of the HRV during the whole recovery period. Greater LF (from the min 5 to 10) and HF (from the min 6 to 10) in the post-exercise period in the H(igh)PT compared to the (Low)PT group (P < 0.05) was observed. These results indicate that exercise training exerts beneficial effects on post-exercise cardiac autonomic control.

Development of Report Turnaround Times in a University Department of Radiology during Implementation of a Reformed Curriculum for Undergraduate Medical Education.

PubMed

Albrecht, Liane; Maurer, Martin H; Seithe, Tim; Braun, Joachim; Gummert, Richard; Auer, Jonas; Sponheuer, Keno; Meyl, Tobias Philipp; Hamm, Bernd; de Bucourt, Maximilian

2018-03-01

 The implementation of a reformed curriculum for undergraduate medical education with a problem-oriented focus and more bedside teaching in small groups increases the academic teaching workload. The aim of this study was to investigate whether this increase in teaching duties is associated with an increase in report turnaround times of radiologists or increased unplanned absence during term times compared with term breaks (lecture-free periods) and over the whole period under investigation.  The database of all radiological examinations performed at a large German university hospital was retrospectively analyzed for a two-year period from the winter term 2011/12 to the summer term 2013. A total of 192 984 radiological examinations performed during this period were included in an analysis of reporting times (i. e., time from end of examination to completion of report) during term times versus term breaks. Reporting times were analyzed for all radiological examinations and for intensive care unit (ICU) patients. In addition, radiologists' schedules were analyzed in terms of teaching duties, unplanned absence, vacation days, and days away from work for education and training.  During the period under investigation, the teaching load increased from overall 1.75 hours/day in the winter term 2011/12 to 6.49 hours/day in the summer term 2013 and in the term break from overall 0.10 hours/day in the winter term 2011/12 to 0.71 hours/day in the summer term 2013. Reporting time increased during this period (p < 0.05) but remained shorter during term times than during term breaks. The difference between term and term break for ICU patients was not significant. There was no increase in unplanned absences during term times.  Overall, radiologists' reporting times increased during the period when the reformed curriculum for undergraduate medical education was implemented. As this was observed both during term and during term breaks, increased teaching duties alone cannot serve as a sole causal explanation. · Digital high-quantitative parameters can be used to evaluate workflow in radiology.. · Reporting time can be a criterion for efficient staffing.. · The acquisition and evaluation of parameters such as reporting times could lead to a more efficient resource allocation by providing hints of changed framework conditions and changing working intensities and/or capicity reserves - which may not be immediately apparent.. · During the period under investigation with the implementation of a teaching-intensive reformed curriculum for undergraduate medical education there was an increase in reporting time, which was not significant in intense care units.. · Since during the period under investigation the increase in reporting times can be stated both during term time and in the lecture free period, the implementation of the reformed curriculum for undergraduate medical education alone cannot serve as a sole causal explanation.. · Albrecht L, Maurer MH, Seithe T et al. Development of the Report Turnaround Times in a University Department of Radiology during Implementation of a Reformed Curriculum for Undergraduate Medical Education. Fortschr Röntgenstr 2018; 190: 259 - 264. © Georg Thieme Verlag KG Stuttgart · New York.

Identification of ground motion features for high-tech facility under far field seismic waves using wavelet packet transform

NASA Astrophysics Data System (ADS)

Huang, Shieh-Kung; Loh, Chin-Hsiung; Chen, Chin-Tsun

2016-04-01

Seismic records collected from earthquake with large magnitude and far distance may contain long period seismic waves which have small amplitude but with dominant period up to 10 sec. For a general situation, the long period seismic waves will not endanger the safety of the structural system or cause any uncomfortable for human activity. On the contrary, for those far distant earthquakes, this type of seismic waves may cause a glitch or, furthermore, breakdown to some important equipments/facilities (such as the high-precision facilities in high-tech Fab) and eventually damage the interests of company if the amplitude becomes significant. The previous study showed that the ground motion features such as time-variant dominant frequencies extracted using moving window singular spectrum analysis (MWSSA) and amplitude characteristics of long-period waves identified from slope change of ground motion Arias Intensity can efficiently indicate the damage severity to the high-precision facilities. However, embedding a large hankel matrix to extract long period seismic waves make the MWSSA become a time-consumed process. In this study, the seismic ground motion data collected from broadband seismometer network located in Taiwan were used (with epicenter distance over 1000 km). To monitor the significant long-period waves, the low frequency components of these seismic ground motion data are extracted using wavelet packet transform (WPT) to obtain wavelet coefficients and the wavelet entropy of coefficients are used to identify the amplitude characteristics of long-period waves. The proposed method is a timesaving process compared to MWSSA and can be easily implemented for real-time detection. Comparison and discussion on this method among these different seismic events and the damage severity to the high-precision facilities in high-tech Fab is made.

The past is the key to the future

USGS Publications Warehouse

Doe, B.R.

1983-01-01

A new major frontier of geological research, which was initiated in the 1970's, involves predicting future geologic trends or events through study of the present and past, rather than trying to understand the past, often using what one knows about the present. Like most scientific frontiers, this one began from practical considerations-environmental concerns. The lack of formal recognition of this frontier results from fragmentation among many Federal agencies and highly focused mission-oriented programs (e.g., earthquake prediction, CO2, nuclear-energy safety, etc.). Most programs aim to predict only the next 50-100 years, but much longer periods of the past need to be studied to do this. Nuclear-waste disposal has sometimes been considered in terms of the next million years, a period of time permitting significant and broad geologic changes. Decreasing public interest in environmental concerns relegates many questions from the realm of applied research back to that of basic research. Most of these questions are so fascinating, however, that the frontier is still worth pursuing. Such questions include whether a phenomenon will or will not take place and the rates at which it can develop (e.g., how fast do rifts form, how fast can a caldera event begin, and how quickly can a glacial maximum arrive?). Common elements of all studies include the historic record, trends in the Quaternary, analogues in various periods of the geologic time scale, and allowance for phenomena never experienced before. Other examples of studies include the Cretaceous as a period of a climatic extreme, an especially interesting time period; establishing the amount of paleocloudiness, a particularly challenging and important research area; acid rain as a possible new phenomenon. Geochemistry has much to contribute to this frontier science. ?? 1983.

Optical photometric variability of 2S 0114+65

NASA Technical Reports Server (NTRS)

Taylor, M.; Finley, J. P.; Kurt, C.; Koenigsberger, G.

1995-01-01

In this paper we present Johnson V photometry of the Be/x-ray binary star system 2S 0114+65. Although this star exhibits periodic variations in x-rays, optical studies have failed to reveal fluctuations greater than 5 millimag. The data presented in this paper provide the first evidence for periodic optical variability in 2S 0114+65. On each of four nights in October 1993, we find low amplitude variations with a period of 2.77 +/- 0.48 h and with a semiamplitude of 4 millimag. This period is in good agreement with results of a comprehensive study of the x-ray data. We explore the possibility that this period represents the pulsational period of the B-star primary and the possibility that it is the rotational period of the neutron star. If the latter is the correct interpretation, we calculate a spin-up time scale of 5 x 10(exp 5) yr.

What time-lag for a retraction search on PubMed?

PubMed

Decullier, Evelyne; Huot, Laure; Maisonneuve, Hervé

2014-06-25

To investigate fraud and errors, scientists have studied cohorts of retraction notices. These researches have been performed using a PubMed search on publication type "retraction of publication" which retrieves the notices of the retractions. We assessed the stability of the indexation of retraction notices over a 15-month period and what was the time-lag to get stability. A search on notices of retraction issued in 2008 was repeated every 3 months during 15 months from February 2011. The first search resulted in 237 notices of retraction. Throughout the study period, 14 discrepancies with the initial search were observed (6%). We found that the number of retraction notices became stable 35 months after the retraction. The time-lag observed in this study has to be taken into account when performing a PubMed search.

2D discontinuous piecewise linear map: Emergence of fashion cycles.

PubMed

Gardini, L; Sushko, I; Matsuyama, K

2018-05-01

We consider a discrete-time version of the continuous-time fashion cycle model introduced in Matsuyama, 1992. Its dynamics are defined by a 2D discontinuous piecewise linear map depending on three parameters. In the parameter space of the map periodicity, regions associated with attracting cycles of different periods are organized in the period adding and period incrementing bifurcation structures. The boundaries of all the periodicity regions related to border collision bifurcations are obtained analytically in explicit form. We show the existence of several partially overlapping period incrementing structures, that is, a novelty for the considered class of maps. Moreover, we show that if the time-delay in the discrete time formulation of the model shrinks to zero, the number of period incrementing structures tends to infinity and the dynamics of the discrete time fashion cycle model converges to those of continuous-time fashion cycle model.

77 FR 58828 - Alaska Energy Authority; Notice of Extension of Time To File Comments on the Proposed Study and...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-24

... Authority; Notice of Extension of Time To File Comments on the Proposed Study and Revised Study Plan On July 16, 2012, Alaska Energy Authority (AEA) filed its proposed study plan for the Susitna-Watana Project... Process, making comments on the study plan due October 14, 2012. During the comment period, AEA finalized...

Normative Beliefs Regarding Aggression in Emerging Adulthood

ERIC Educational Resources Information Center

Nelson, David A.; Springer, Melanie M.; Nelson, Larry J.; Bean, Nathaniel H.

2008-01-01

Few studies have examined the nature of aggression in emerging adulthood (ages 18-25), a unique developmental period wherein relationships become increasingly important and intimate. Consistent with a greater emphasis on relationships, relationally manipulative forms of aggression may be particularly salient during this time period. Based on…

Artificial neural network with backpropagation learning to predict mean monthly total ozone in Arosa, Switzerland

NASA Astrophysics Data System (ADS)

Chattopadhyay, Surajit; Bandyopadhyay, Goutami

2007-01-01

Present study deals with the mean monthly total ozone time series over Arosa, Switzerland. The study period is 1932-1971. First of all, the total ozone time series has been identified as a complex system and then Artificial Neural Networks models in the form of Multilayer Perceptron with back propagation learning have been developed. The models are Single-hidden-layer and Two-hidden-layer Perceptrons with sigmoid activation function. After sequential learning with learning rate 0.9 the peak total ozone period (February-May) concentrations of mean monthly total ozone have been predicted by the two neural net models. After training and validation, both of the models are found skillful. But, Two-hidden-layer Perceptron is found to be more adroit in predicting the mean monthly total ozone concentrations over the aforesaid period.

Trajectories of Sleep Quality and Associations with Mood during the Perinatal Period.

PubMed

Tomfohr, Lianne M; Buliga, Elena; Letourneau, Nicole L; Campbell, Tavis S; Giesbrecht, Gerald F

2015-08-01

The aim of this study was to investigate trajectories of sleep quality and associations with mood in the perinatal period. Although it is commonly accepted that subjective sleep quality declines during pregnancy and the transition to parenthood, some women may follow qualitatively distinct trajectories. Sleep quality was assessed by the Pittsburgh Sleep Quality Index (PSQI). Data were collected from 293 women at four time points: during early pregnancy, at Time 1 (T1; < 22 w gestational age [GA]; late pregnancy, at Time 2 (T2; 32 w GA); during the postnatal period at Time 3 (T3; 3 mo postpartum); and Time 4 (T4; 6 mo postpartum). A group-based semiparametric mixture model was used to estimate patterns of sleep quality throughout the perinatal period. Four trajectory groups were identified, including patterns defined by high sleep quality throughout (21.5%), mild decrease in sleep quality (59.5%), significant decrease in sleep quality (12.3%) and a group with poor sleep quality throughout (6.7%). Women who had the worst sleep quality at Time 1 and those who experienced significant increases in sleep problems throughout pregnancy were also the groups who reported the highest levels of anxiety and depressive symptoms in early pregnancy and the lowest levels of social support. After controlling for covariates, the groups with worst subjective sleep quality during pregnancy were also the most likely to experience high symptoms of depression in the postpartum period. Most of the women in our sample reported mild sleep disturbances through the perinatal period. A subgroup of women reported a significant decline in sleep quality from early to late pregnancy and another reported poor subjective sleep quality throughout pregnancy; these groups had the greatest risk of experiencing high symptoms of depression in the postpartum period. © 2015 Associated Professional Sleep Societies, LLC.

How Robust Are the Surface Temperature Fingerprints of the Atlantic Overturning Meridional Circulation on Monthly Time Scales?

NASA Astrophysics Data System (ADS)

Alexander-Turner, R.; Ortega, P.; Robson, J. I.

2018-04-01

It has been suggested that changes in the Atlantic Meridional Overturning Circulation (AMOC) can drive sea surface temperature (SST) on monthly time scales (Duchez et al., 2016, https://doi.org/10.1002/2017GB005667). However, with only 11 years of continuous observations, the validity of this result over longer, or different, time periods is uncertain. In this study, we use a 120 yearlong control simulation from a high-resolution climate model to test the robustness of the AMOC fingerprints. The model reproduces the observed AMOC seasonal cycle and its variability, and the observed 5-month lagged AMOC-SST fingerprints derived from 11 years of data. However, the AMOC-SST fingerprints are very sensitive to the particular time period considered. In particular, both the Florida current and the upper mid-ocean transport produce highly inconsistent fingerprints when using time periods shorter than 30 years. Therefore, several decades of RAPID observations will be necessary to determine the real impact of the AMOC on SSTs at monthly time scales.

Historical DNA reveals the demographic history of Atlantic cod (Gadus morhua) in medieval and early modern Iceland

PubMed Central

Ólafsdóttir, Guðbjörg Ásta; Westfall, Kristen M.; Edvardsson, Ragnar; Pálsson, Snæbjörn

2014-01-01

Atlantic cod (Gadus morhua) vertebrae from archaeological sites were used to study the history of the Icelandic Atlantic cod population in the time period of 1500–1990. Specifically, we used coalescence modelling to estimate population size and fluctuations from the sequence diversity at the cytochrome b (cytb) and Pantophysin I (PanI) loci. The models are consistent with an expanding population during the warm medieval period, large historical effective population size (NE), a marked bottleneck event at 1400–1500 and a decrease in NE in early modern times. The model results are corroborated by the reduction of haplotype and nucleotide variation over time and pairwise population distance as a significant portion of nucleotide variation partitioned across the 1550 time mark. The mean age of the historical fished stock is high in medieval times with a truncation in age in early modern times. The population size crash coincides with a period of known cooling in the North Atlantic, and we conclude that the collapse may be related to climate or climate-induced ecosystem change. PMID:24403343

Historical DNA reveals the demographic history of Atlantic cod (Gadus morhua) in medieval and early modern Iceland.

PubMed

Ólafsdóttir, Guðbjörg Ásta; Westfall, Kristen M; Edvardsson, Ragnar; Pálsson, Snæbjörn

2014-02-22

Atlantic cod (Gadus morhua) vertebrae from archaeological sites were used to study the history of the Icelandic Atlantic cod population in the time period of 1500-1990. Specifically, we used coalescence modelling to estimate population size and fluctuations from the sequence diversity at the cytochrome b (cytb) and Pantophysin I (PanI) loci. The models are consistent with an expanding population during the warm medieval period, large historical effective population size (NE), a marked bottleneck event at 1400-1500 and a decrease in NE in early modern times. The model results are corroborated by the reduction of haplotype and nucleotide variation over time and pairwise population distance as a significant portion of nucleotide variation partitioned across the 1550 time mark. The mean age of the historical fished stock is high in medieval times with a truncation in age in early modern times. The population size crash coincides with a period of known cooling in the North Atlantic, and we conclude that the collapse may be related to climate or climate-induced ecosystem change.

Dynamics of protein and lipid intake regulation of rainbow trout studied with a wide lipid range of encapsulated diets and self-feeders.

PubMed

Forsman, Antti; Ruohonen, Kari

2009-01-08

Feed intake in fish is examined extensively but there is not much information about the dynamics of regulation i.e. how fish react to different diets, and how these reactions change, over a longer period of time. The present study was designed to evaluate the dynamics of food intake regulation in rainbow trout over a very wide range of dietary protein and lipid levels; from a very low lipid level (5%) to an extremely high level (55%). The study was conducted with three subsequent 40-day blocks of 20 fish and the intake dynamics of the lipid effect were studied by splitting the 40-day experimental period to shorter periods of 10 days. Depending on a diet the rainbow trout were more willing to ingest larger surpluses of both protein and lipid during the periods 0-10, 10-20 and 20-30 days if compared with the anticipated nutritional intake target of rainbow trout. A strong regulatory response against high lipid intake was seen during the last period (days 30-40) leading not only to a decrease in lipid intake but much more drastic decrease in protein intake. Thus, a significant nonlinear interaction between time and dietary protein and lipid was found indicating that the effect of protein and lipid was dynamic.

[Distant healing and diabetes mellitus. A pilot study].

PubMed

Ebneter, M; Binder, M; Kristof, O; Walach, H; Saller, R

2002-02-01

The Institut für Grenzgebiete der Psychologie und Psychohygiene, Freiburg (IGPP) in cooperation with the Abteilung Naturheilkunde, University Hospital, Zürich investigated whether Distant Healing has a beneficial effect on patients with diabetes mellitus regarding the state of the disease and quality of life. The goal of the pilot study was to observe the progression of the disease with various medical and psychological measures and to explore which of them might be sensitive for measuring possible treatment effects. 14 diabetic patients were observed for a period of 16 weeks. Within this time they underwent a treatment of 4 consecutive weeks (weeks 9-12) by 5 experienced and trustworthy healers each. Patients were informed about the duration of the treatment but not about the time point of its beginning. Patients and healers never met and there was no contact between researchers and patients during the study period. With regard to medical parameters, reduction in fructosamine level was observed during the healing period, increasing fructosamine level after the end of the healing period. Sensitivity, measured only at the beginning and at the end of the study period, decreased significantly. The other parameters showed some significant changes but there was no correlation to the Distant Healing intervention. Regarding the psychological data, only improvements were observed. The results indicate the possibility that a Distant Healing intervention could have certain effects on patients with diabetes mellitus. Copyright 2002 S. Karger GmbH, Freiburg

Surface composition XPS analysis of a plasma treated polystyrene: Evolution over long storage periods.

PubMed

Ba, Ousmane M; Marmey, Pascal; Anselme, Karine; Duncan, Anthony C; Ponche, Arnaud

2016-09-01

A polystyrene surface (PS) was initially treated by cold nitrogen and oxygen plasma in order to incorporate in particular amine and hydroxyl functions, respectively. The evolution of the chemical nature of the surface was further monitored over a long time period (580 days) by chemical assay, XPS and contact angle measurements. Surface density quantification of primary amine groups was performed using three chemical amine assays: 4-nitrobenzaldehyde (4-NBZ), Sulfo succinimidyl 6-[3'(2 pyridyldithio)-pionamido] hexanoate (Sulfo-LC-SPDP) and iminothiolane (ITL). The results showed amine densities were in the range of 2 per square nanometer (comparable to the results described in the literature) after 5min of nitrogen plasma treatment. Over the time period investigated, chemical assays, XPS and contact angles suggest a drastic significant evolution of the chemical nature of the surface within the first two weeks. Beyond that time period and up to almost two years, nitrogen plasma modified substrates exhibits a slow and continuous oxidation whereas oxygen plasma modifed polystyrene surface is chemically stable after two weeks of storage. The latter appeared to "ease of" showing relatively mild changes within the one year period. Our results suggest that it may be preferable to wait for a chemical "stabilization" period of two weeks before subsequent covalent immobilization of proteins onto the surface. The originality of this work resides in the study of the plasma treated surface chemistry evolution over long periods of storage time (580 days) considerably exceeding those described in the literature. Copyright © 2016 Elsevier B.V. All rights reserved.

Understanding exercise self-efficacy and barriers to leisure-time physical activity among postnatal women.

PubMed

Cramp, Anita G; Bray, Steven R

2011-07-01

Studies have demonstrated that postnatal women are at high risk for physical inactivity and generally show lower levels of leisure-time physical activity (LTPA) compared to prepregnancy. The overall purpose of the current study was to investigate social cognitive correlates of LTPA among postnatal women during a 6-month period following childbirth. A total of 230 women (mean age = 30.9) provided descriptive data regarding barriers to LTPA and completed measures of LTPA and self-efficacy (exercise and barrier) for at least one of the study data collection periods. A total of 1,520 barriers were content analyzed. Both exercise and barrier self-efficacy were positively associated with subsequent LTPA. Exercise self-efficacy at postnatal week 12 predicted LTPA from postnatal weeks 12 to 18 (β = .40, R (2) = .18) and exercise self-efficacy at postnatal week 24 predicted LTPA during weeks 24-30 (β = .49, R (2) = .30). Barrier self-efficacy at week 18 predicted LTPA from weeks 18 to 24 (β = .33, R (2) = .13). The results of the study identify a number of barriers to LTPA at multiple time points closely following childbirth which may hinder initiation, resumption or maintenance of LTPA. The results also suggest that higher levels of exercise and barrier self-efficacy are prospectively associated with higher levels of LTPA in the early postnatal period. Future interventions should be designed to investigate causal effects of developing participants' exercise and barrier self-efficacy for promoting and maintaining LTPA during the postnatal period.

Network analysis of returns and volume trading in stock markets: The Euro Stoxx case

NASA Astrophysics Data System (ADS)

Brida, Juan Gabriel; Matesanz, David; Seijas, Maria Nela

2016-02-01

This study applies network analysis to analyze the structure of the Euro Stoxx market during the long period from 2002 up to 2014. The paper generalizes previous research on stock market networks by including asset returns and volume trading as the main variables to study the financial market. A multidimensional generalization of the minimal spanning tree (MST) concept is introduced, by adding the role of trading volume to the traditional approach which only includes price returns. Additionally, we use symbolization methods to the raw data to study the behavior of the market structure in different, normal and critical, situations. The hierarchical organization of the network is derived, and the MST for different sub-periods of 2002-2014 is created to illustrate how the structure of the market evolves over time. From the structural topologies of these trees, different clusters of companies are identified and analyzed according to their geographical and economic links. Two important results are achieved. Firstly, as other studies have highlighted, at the time of the financial crisis after 2008 the network becomes a more centralized one. Secondly and most important, during our second period of analysis, 2008-2014, we observe that hierarchy becomes more country-specific where different sub-clusters of stocks belonging to France, Germany, Spain or Italy are found apart from their business sector group. This result may suggest that during this period of time financial investors seem to be worried most about country specific economic circumstances.

Different time trends of caloric and fat intake between statin users and nonusers among US adults: gluttony in the time of statins?

PubMed

Sugiyama, Takehiro; Tsugawa, Yusuke; Tseng, Chi-Hong; Kobayashi, Yasuki; Shapiro, Martin F

2014-07-01

Both dietary modification and use of statins can lower blood cholesterol. The increase in caloric intake among the general population is reported to have plateaued in the last decade, but no study has examined the relationship between the time trends of caloric intake and statin use. To examine the difference in the temporal trends of caloric and fat intake between statin users and nonusers among US adults. A repeated cross-sectional study in a nationally representative sample of 27,886 US adults, 20 years or older, from the National Health and Nutrition Examination Survey, 1999 through 2010. Statin use. Caloric and fat intake measured through 24-hour dietary recall. Generalized linear models with interaction term between survey cycle and statin use were constructed to investigate the time trends of dietary intake for statin users and nonusers after adjustment for possible confounders. We calculated model-adjusted caloric and fat intake using these models and examined if the time trends differed by statin use. Body mass index (BMI) changes were also compared between statin users and nonusers. In the 1999-2000 period, the caloric intake was significantly less for statin users compared with nonusers (2000 vs 2179 kcal/d; P = .007). The difference between the groups became smaller as time went by, and there was no statistical difference after the 2005-2006 period. Among statin users, caloric intake in the 2009-2010 period was 9.6% higher (95% CI, 1.8-18.1; P = .02) than that in the 1999-2000 period. In contrast, no significant change was observed among nonusers during the same study period. Statin users also consumed significantly less fat in the 1999-2000 period (71.7 vs 81.2 g/d; P = .003). Fat intake increased 14.4% among statin users (95% CI, 3.8-26.1; P = .007) while not changing significantly among nonusers. Also, BMI increased more among statin users (+1.3) than among nonusers (+0.4) in the adjusted model (P = .02). Caloric and fat intake have increased among statin users over time, which was not true for nonusers. The increase in BMI was faster for statin users than for nonusers. Efforts aimed at dietary control among statin users may be becoming less intensive. The importance of dietary composition may need to be reemphasized for statin users.

A Primer on Longitudinal Data Analysis in Education. Technical Report #1320

ERIC Educational Resources Information Center

Nese, Joseph F. T.; Lai, Cheng-Fei; Anderson, Daniel

2013-01-01

Longitudinal data analysis in education is the study growth over time. A longitudinal study is one in which repeated observations of the same variables are recorded for the same individuals over a period of time. This type of research is known by many names (e.g., time series analysis or repeated measures design), each of which can imply subtle…

[Changes of heart electrophysiological parameters after destruction of epicardial subplexuses that innervate sinoatrial node].

PubMed

Kulboka, Arūnas; Veikutis, Vincentas; Pauza, Dainius Haroldas; Lekas, Raimundas

2003-01-01

The aims of present study were to verify the topography of the intracardiac nerve subplexuses (INS) by using electrophysiological methods, its relations with sinoatrial (SA) node function and to investigate possibility of selective surgical SA node denervation. Fifteen mongrel dogs of either sex weighing 8 to 15 kg were used for electrophysiological studies. Both cervical vagosympathetic trunks were isolated and crushed by tight ligatures. Nervus subplexuses destructions were performed by cryocoagulation in three zones located around the right superior vena cava: ventral, lateral and dorsal. The sinus rhythm, SA node function recovery time, AV node conductivity, AV node and atrial effective refractory period were measured. Five experiments in each of three zones were performed. Experimental data show that destruction of the epicardial nerves has different effect on electrophysiological parameters. After destruction of the anterior zone of the right atrium the sinus rhythm decreased on an average by 11.6%; SA node function recovery time prolonged by 7.2%; AV node conductivity decreased by 13.1%; AV node effective refractory period prolonged by 12.9% and atrial effective refractory period, by 10.9 %. Measurements of electrophysiological parameters after intravenous injection of atropine sulphate show that sinus rhythm decreased on an average by 23.4%; SA node function recovery time increased by 9.1%; the conductivity of AV node decreased by 10.2%; AV node effective refractory period prolonged by 15.4% and atrial effective refractory period, by 13.2%. After destruction of the intracardiac nerves of the lateral zone, the sinus rhythm decreased by 15.7%; SA node function recovery time increased by 16.3%; AV node conductivity decreased by 8.3%; AV node effective refractory period and atrial effective refractory period prolonged by 11.9% and 10.0%, respectively. After the atropine sulphate intravenous injection, the sinus rhythm decreased on an average by 7.1%, SA node function recovery time prolonged by 7.1%, AV conductivity decreased by 9.1%, AV node effective refractory period increased by 12.4%, and atrial effective refractory period prolonged by 12.5%. After destruction of the nerves in the dorsal zone the changes of electrophysiological parameters were opposite to those obtained after destruction of the nerve tracts in the anterior or lateral zones: the sinus rhythm increased on an average by 4.3%; SA node function recovery time shortened by 8.8%; AV conductivity increased by 9.7%; AV node and atrial effective refractory period decreased by 12.3% and 12.1%, respectively. After intravenous atropine sulphate infusion, sinus rhythm decreased on an average by 8.3%; SA node function recovery time prolonged by 9.6%; AV node conductivity decreased by 5%; AV node and atrial effective refractory period prolonged by 4.2% and 5.2%, respectively. The average changes of electrophysiological parameters before and after INS destruction shows that cryocoagulation of ventral and lateral zones eliminates the effects of sympathetic tone to SA and AV nodal activity. Cryocoagulation of dorsal zone eliminates the effects of nervus vagus to both nodal structures. These findings shows the possibility alter or correct SA node function by making selective surgical SA node denervation.

Reliability of plasma lipopolysaccharide-binding protein (LBP) from repeated measures in healthy adults.

PubMed

Citronberg, Jessica S; Wilkens, Lynne R; Lim, Unhee; Hullar, Meredith A J; White, Emily; Newcomb, Polly A; Le Marchand, Loïc; Lampe, Johanna W

2016-09-01

Plasma lipopolysaccharide-binding protein (LBP), a measure of internal exposure to bacterial lipopolysaccharide, has been associated with several chronic conditions and may be a marker of chronic inflammation; however, no studies have examined the reliability of this biomarker in a healthy population. We examined the temporal reliability of LBP measured in archived samples from participants in two studies. In Study one, 60 healthy participants had blood drawn at two time points: baseline and follow-up (either three, six, or nine months). In Study two, 24 individuals had blood drawn three to four times over a seven-month period. We measured LBP in archived plasma by ELISA. Test-retest reliability was estimated by calculating the intraclass correlation coefficient (ICC). Plasma LBP concentrations showed moderate reliability in Study one (ICC 0.60, 95 % CI 0.43-0.75) and Study two (ICC 0.46, 95 % CI 0.26-0.69). Restricting the follow-up period improved reliability. In Study one, the reliability of LBP over a three-month period was 0.68 (95 % CI: 0.41-0.87). In Study two, the ICC of samples taken ≤seven days apart was 0.61 (95 % CI 0.29-0.86). Plasma LBP concentrations demonstrated moderate test-retest reliability in healthy individuals with reliability improving over a shorter follow-up period.

The calculation of the viscosity from the autocorrelation function using molecular and atomic stress tensors

NASA Astrophysics Data System (ADS)

Cui, S. T.

The stress-stress correlation function and the viscosity of a united-atom model of liquid decane are studied by equilibrium molecular dynamics simulation using two different formalisms for the stress tensor: the atomic and the molecular formalisms. The atomic and molecular correlation functions show dramatic difference in short-time behaviour. The integrals of the two correlation functions, however, become identical after a short transient period whichis significantly shorter than the rotational relaxation time of the molecule. Both reach the same plateau value in a time period corresponding to this relaxation time. These results provide a convenient guide for the choice of the upper integral time limit in calculating the viscosity by the Green-Kubo formula.

Operation of the University of Hawaii 2.2 M Telescope on Mauna KEA

NASA Technical Reports Server (NTRS)

Hall, Donald N. B.

1997-01-01

During the period October 5, 1993-October 31, 1997, operation of the University of Hawaii's 2.2-meter telescope was partially funded by NASA Planetary Astronomy Program. During the grant period, the fraction of observing time devoted to studies of solar system objects (e.g., planets, planetary satellites, asteroids, and comets) was approximately 24% (i.e., it exceeded the fractional funding provided by this NASA grant). The number of nights allocated to planetary observing time is summarized. Proposals for use of the solar system observing time coming from within and outside the University of Hawaii competed for this observing time on an equal basis; applications were judged on scientific merit by a time allocation committee at the University of Hawaii.

24 CFR 1720.165 - Time computation.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Time computation. 1720.165 Section... Proceedings General Provisions § 1720.165 Time computation. Computation of any period of time prescribed or... or default initiating such period of time shall have occurred. When the last day of the period so...

24 CFR 1720.165 - Time computation.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 24 Housing and Urban Development 5 2013-04-01 2013-04-01 false Time computation. 1720.165 Section... Proceedings General Provisions § 1720.165 Time computation. Computation of any period of time prescribed or... or default initiating such period of time shall have occurred. When the last day of the period so...

24 CFR 1720.165 - Time computation.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 24 Housing and Urban Development 5 2012-04-01 2012-04-01 false Time computation. 1720.165 Section... Proceedings General Provisions § 1720.165 Time computation. Computation of any period of time prescribed or... or default initiating such period of time shall have occurred. When the last day of the period so...

24 CFR 1720.165 - Time computation.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 24 Housing and Urban Development 5 2011-04-01 2011-04-01 false Time computation. 1720.165 Section... Proceedings General Provisions § 1720.165 Time computation. Computation of any period of time prescribed or... or default initiating such period of time shall have occurred. When the last day of the period so...

24 CFR 1720.165 - Time computation.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 24 Housing and Urban Development 5 2014-04-01 2014-04-01 false Time computation. 1720.165 Section... Proceedings General Provisions § 1720.165 Time computation. Computation of any period of time prescribed or... or default initiating such period of time shall have occurred. When the last day of the period so...

Long-term side-effects of intermittent androgen suppression therapy in prostate cancer: results of a phase II study.

PubMed

Malone, Shawn; Perry, Gad; Segal, Roanne; Dahrouge, Simone; Crook, Juanita

2005-09-01

To assess the feasibility and tolerability of intermittent androgen suppression therapy (IAS) in prostate cancer. Patients with recurrent or metastic prostate cancer received cyclical periods of treatment with leuprolide acetate and nilutamide for 8 months, and rest periods. Cycles were repeated at progression until the treatment failed to achieve normal prostate-specific antigen (PSA) levels. Patients were followed with PSA level, testosterone level, haemoglobin level, weight and bone mineral density evaluations. The median time to treatment failure, recovery from anaemia, or normalization of testosterone level was estimated by the Kaplan-Meier method. In all, 95 patients received 245 cycles; the median duration of rest periods was 8 months and median time to treatment failure 47 months. Testosterone recovery during rest periods was documented in 117 (61%) of cycles. Anaemia was mild and reported in 33%, 44% and 67% of cycles 1, 2 and 3, respectively. Sexual function recovered during the rest periods in 47% of cycles. There was no significant overall change in body mass index at the end of the treatment period. Osteoporosis was documented in at least one site evaluated in 41 patients (37%). IAS has the potential to reduce side-effects, including recovery of haemoglobin level, return of sexual function and absence of weight gain at the end of the study period.

Comparison of methods for non-stationary hydrologic frequency analysis: Case study using annual maximum daily precipitation in Taiwan

NASA Astrophysics Data System (ADS)

Chen, Po-Chun; Wang, Yuan-Heng; You, Gene Jiing-Yun; Wei, Chih-Chiang

2017-02-01

Future climatic conditions likely will not satisfy stationarity assumption. To address this concern, this study applied three methods to analyze non-stationarity in hydrologic conditions. Based on the principle of identifying distribution and trends (IDT) with time-varying moments, we employed the parametric weighted least squares (WLS) estimation in conjunction with the non-parametric discrete wavelet transform (DWT) and ensemble empirical mode decomposition (EEMD). Our aim was to evaluate the applicability of non-parameter approaches, compared with traditional parameter-based methods. In contrast to most previous studies, which analyzed the non-stationarity of first moments, we incorporated second-moment analysis. Through the estimation of long-term risk, we were able to examine the behavior of return periods under two different definitions: the reciprocal of the exceedance probability of occurrence and the expected recurrence time. The proposed framework represents an improvement over stationary frequency analysis for the design of hydraulic systems. A case study was performed using precipitation data from major climate stations in Taiwan to evaluate the non-stationarity of annual maximum daily precipitation. The results demonstrate the applicability of these three methods in the identification of non-stationarity. For most cases, no significant differences were observed with regard to the trends identified using WLS, DWT, and EEMD. According to the results, a linear model should be able to capture time-variance in either the first or second moment while parabolic trends should be used with caution due to their characteristic rapid increases. It is also observed that local variations in precipitation tend to be overemphasized by DWT and EEMD. The two definitions provided for the concept of return period allows for ambiguous interpretation. With the consideration of non-stationarity, the return period is relatively small under the definition of expected recurrence time comparing to the estimation using the reciprocal of the exceedance probability of occurrence. However, the calculation of expected recurrence time is based on the assumption of perfect knowledge of long-term risk, which involves high uncertainty. When the risk is decreasing with time, the expected recurrence time will lead to the divergence of return period and make this definition inapplicable for engineering purposes.

Explaining Changes in the Patterns of Black Suicide in the United States from 1981 to 2002: An Age, Cohort, and Period Analysis

ERIC Educational Resources Information Center

Joe, Sean

2006-01-01

To explore the different trends of suicide incidence among Blacks and possible contributing factors, the current study compared national epidemiologic data of suicide in the United States from 1981 to 2002. For the first time, period and birth-cohort effects on the incidence trends of Black suicide were evaluated using an age-period-cohort…

Patterns of objectively measured sedentary time in 10- to 12-year-old Belgian children: an observational study within the ENERGY-project.

PubMed

Verloigne, Maïté; Ridgers, Nicola D; Chinapaw, Mai; Altenburg, Teatske M; Bere, Elling; Van Lippevelde, Wendy; Cardon, Greet; Brug, Johannes; De Bourdeaudhuij, Ilse

2017-06-14

This study examined the frequency of and differences in sedentary bouts of different durations and the total time spent in sedentary bouts on a weekday, a weekend day, during school hours, during after-school hours and in the evening period in a sample of 10- to 12-year-old Belgian children. Accelerometer data were collected as part of the ENERGY-project in Belgium (n = 577, 10.9 ± 0.7 years, 53% girls) in 2011. Differences in total sedentary time, sedentary bouts of 2-5, 5-10, 10-20, 20-30 and ≥30 min and total time accumulated in those bouts were examined on a weekday, a weekend day, during school hours, during after-school hours and in the evening period, using multilevel analyses in MLwiN 2.22. More than 60% of the participants' waking time was spent sedentary. Children typically engaged in short sedentary bouts of 2-5 and 5-10 min, which contributed almost 50% towards their total daily sedentary time. Although the differences were very small, children engaged in significantly fewer sedentary bouts of nearly all durations during after-school hours compared to during school hours and in the evening period. Children also engaged in significantly fewer sedentary bouts of 5-10, 10-20, and 20-30 min per hour on a weekend day than on a weekday. Although primary school children spend more than 60% of their waking time sedentary, they generally engaged in short sedentary bouts. Children's sedentary bouts were slightly longer on weekdays, particularly during school hours and in the evening period, although the differences were very small. These results suggest that in this age group, interventions focusing on reducing total sedentary time rather than interrupting prolonged sedentary time are needed.

Impact of an electronic health record operating room management system in ophthalmology on documentation time, surgical volume, and staffing.

PubMed

Sanders, David S; Read-Brown, Sarah; Tu, Daniel C; Lambert, William E; Choi, Dongseok; Almario, Bella M; Yackel, Thomas R; Brown, Anna S; Chiang, Michael F

2014-05-01

Although electronic health record (EHR) systems have potential benefits, such as improved safety and quality of care, most ophthalmology practices in the United States have not adopted these systems. Concerns persist regarding potential negative impacts on clinical workflow. In particular, the impact of EHR operating room (OR) management systems on clinical efficiency in the ophthalmic surgery setting is unknown. To determine the impact of an EHR OR management system on intraoperative nursing documentation time, surgical volume, and staffing requirements. For documentation time and circulating nurses per procedure, a prospective cohort design was used between January 10, 2012, and January 10, 2013. For surgical volume and overall staffing requirements, a case series design was used between January 29, 2011, and January 28, 2013. This study involved ophthalmic OR nurses (n = 13) and surgeons (n = 25) at an academic medical center. Electronic health record OR management system implementation. (1) Documentation time (percentage of operating time documenting [POTD], absolute documentation time in minutes), (2) surgical volume (procedures/time), and (3) staffing requirements (full-time equivalents, circulating nurses/procedure). Outcomes were measured during a baseline period when paper documentation was used and during the early (first 3 months) and late (4-12 months) periods after EHR implementation. There was a worsening in total POTD in the early EHR period (83%) vs paper baseline (41%) (P < .001). This improved to baseline levels by the late EHR period (46%, P = .28), although POTD in the cataract group remained worse than at baseline (64%, P < .001). There was a worsening in absolute mean documentation time in the early EHR period (16.7 minutes) vs paper baseline (7.5 minutes) (P < .001). This improved in the late EHR period (9.2 minutes) but remained worse than in the paper baseline (P < .001). While cataract procedures required more circulating nurses in the early EHR (mean, 1.9 nurses/procedure) and late EHR (mean, 1.5 nurses/procedure) periods than in the paper baseline (mean, 1.0 nurses/procedure) (P < .001), overall staffing requirements and surgical volume were not significantly different between the periods. Electronic health record OR management system implementation was associated with worsening of intraoperative nursing documentation time especially in shorter procedures. However, it is possible to implement an EHR OR management system without serious negative impacts on surgical volume and staffing requirements.

Estimating Benzene Exposure Level over Time and by Industry Type through a Review of Literature on Korea.

PubMed

Park, Donguk; Choi, Sangjun; Ha, Kwonchul; Jung, Hyejung; Yoon, Chungsik; Koh, Dong-Hee; Ryu, Seunghun; Kim, Soogeun; Kang, Dongmug; Yoo, Kyemook

2015-09-01

The major purpose of this study is to construct a retrospective exposure assessment for benzene through a review of literature on Korea. Airborne benzene measurements reported in 34 articles were reviewed. A total of 15,729 individual measurements were compiled. Weighted arithmetic means [AM(w)] and their variance calculated across studies were summarized according to 5-year period intervals (prior to the 1970s through the 2010s) and industry type. Industries were classified according to Korea Standard Industrial Classification (KSIC) using information provided in the literature. We estimated quantitative retrospective exposure to benzene for each cell in the matrix through a combination of time and KSIC. Analysis of the AM(w) indicated reductions in exposure levels over time, regardless of industry, with mean levels prior to the 1980-1984 period of 50.4 ppm (n = 2,289), which dropped to 2.8 ppm (n = 305) in the 1990-1994 period, and to 0.1 ppm (n = 294) in the 1995-1999 period. There has been no improvement since the 2000s, when the AM(w) of 4.3 ppm (n = 6,211) for the 2005-2009 period and 4.5 ppm (n = 3,358) for the 2010-2013 period were estimated. A comparison by industry found no consistent patterns in the measurement results. Our estimated benzene measurements can be used to determine not only the possibility of retrospective exposure to benzene, but also to estimate the level of quantitative or semiquantitative retrospective exposure to benzene.

Chromosomal rearrangements and gene flow over time in an inter-specific hybrid zone of the Sorex araneus group.

PubMed

Yannic, G; Basset, P; Hausser, J

2009-06-01

Most hybrid zones have existed for hundreds or thousands of years but have generally been observed for only a short time period. Studies extending over periods long enough to track evolutionary changes in the zones or assess the ultimate outcome of hybridization are scarce. Here, we describe the evolution over time of the level of genetic isolation between two karyotypically different species of shrews (Sorex araneus and Sorex antinorii) at a hybrid zone located in the Swiss Alps. We first evaluated hybrid zone movement by contrasting patterns of gene flow and changes in cline parameters (centre and width) using 24 microsatellite loci, between two periods separated by 10 years apart. Additionally, we tested the role of chromosomal rearrangements on gene flow by analysing microsatellite loci located on both rearranged and common chromosomes to both species. We did not detect any movement of the hybrid zone during the period analysed, suggesting that the zone is a typical tension zone. However, the gene flow was significantly lower among the rearranged than the common chromosomes for the second period, whereas the difference was only marginally significant for the first period. This further supports the role of chromosomal rearrangements on gene flow between these taxa.

Circadian periodicity of resistance to ionizing radiation in the pocket mouse.

NASA Technical Reports Server (NTRS)

Lindberg, R. G.; Hayden, P.; Gambino, J. J.

1971-01-01

Investigation of the response of pocket mice to Co 60 irradiation delivered at two times of day - namely, the predicted high and low points of the metabolic rate. The validity of torpor as an assay of the circadian period of body temperature in pocket mice and as a basis for selecting irradiation times is examined. A study is made of the mitotic activity in the pocket mouse intestinal epithelium as an example of a physiological rhythm which might influence radiation sensitivity. The results of tests in which pocket mice were exposed to ionizing radiation at two different times of day are cited. It is found that under the investigated conditions pocket mice irradiated during their metabolically active period (2330 hr) live significantly longer than those irradiated while their metabolic rate is low (0900 hr).

15 CFR 904.4 - Computation of time periods.

Code of Federal Regulations, 2010 CFR

2010-01-01

...) NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE GENERAL REGULATIONS CIVIL PROCEDURES General § 904.4 Computation of time periods. For a NOVA, NOPS or NIDP, the 30 day response period... business day. This method of computing time periods also applies to any act, such as paying a civil penalty...

15 CFR 904.4 - Computation of time periods.

Code of Federal Regulations, 2011 CFR

2011-01-01

...) NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE GENERAL REGULATIONS CIVIL PROCEDURES General § 904.4 Computation of time periods. For a NOVA, NOPS or NIDP, the 30 day response period... business day. This method of computing time periods also applies to any act, such as paying a civil penalty...

Environment, genes, and experience: lessons from behavior genetics.

PubMed

Barsky, Philipp I

2010-11-01

The article reviews the theoretical analysis of the problems inherent in studying the environment within behavior genetics across several periods in the development of environmental studies in behavior genetics and proposes some possible alternatives to traditional approaches to studying the environment in behavior genetics. The first period (from the end of the 1920s to the end of the 1970s), when the environment was not actually studied, is called pre-environmental; during this time, the basic principles and theoretical models of understanding environmental effects in behavior genetics were developed. The second period is characterized by the development of studies on environmental influences within the traditional behavior genetics paradigm; several approaches to studying the environment emerged in behavior genetics during this period, from the beginning of the 1980s until today. At the present time, the field is undergoing paradigmatic changes, concerned with methodology, theory, and mathematical models of genotype-environment interplay; this might be the beginning of a third period of development of environmental studies in behavior genetics. In another part, the methodological problems related to environmental studies in behavior genetics are discussed. Although the methodology used in differential psychology is applicable for assessment of differences between individuals, it is insufficient to explain the sources of these differences. In addition, we stress that psychoanalytic studies of twins and their experiences, initiated in the 1930s and continued episodically until the 1980s, could bring an interesting methodology and contribute to the explanation of puzzling findings from environmental studies of behavior genetics. Finally, we will conclude with implications from the results of environmental studies in behavior genetics, including methodological issues. Copyright © 2010 Elsevier Ltd. All rights reserved.

Structure and dating errors in the geologic time scale and periodicity in mass extinctions

NASA Technical Reports Server (NTRS)

Stothers, Richard B.

1989-01-01

Structure in the geologic time scale reflects a partly paleontological origin. As a result, ages of Cenozoic and Mesozoic stage boundaries exhibit a weak 28-Myr periodicity that is similar to the strong 26-Myr periodicity detected in mass extinctions of marine life by Raup and Sepkoski. Radiometric dating errors in the geologic time scale, to which the mass extinctions are stratigraphically tied, do not necessarily lessen the likelihood of a significant periodicity in mass extinctions, but do spread the acceptable values of the period over the range 25-27 Myr for the Harland et al. time scale or 25-30 Myr for the DNAG time scale. If the Odin time scale is adopted, acceptable periods fall between 24 and 33 Myr, but are not robust against dating errors. Some indirect evidence from independently-dated flood-basalt volcanic horizons tends to favor the Odin time scale.

Mass Communication Research Trends from 1980 to 1999.

ERIC Educational Resources Information Center

Kamhawi, Rasha; Weaver, David

2003-01-01

Uses thematic meta-analysis to examine study method, medium and area of focus, theoretical approach, funding source, and time period covered in research articles published in 10 major mass communications journals during the 1980 to 1999 period. Finds that qualitative research methods continued to be much less common than quantitative methods…

Getting Students in the Journal-Keeping Habit.

ERIC Educational Resources Information Center

Hildebrandt, Peter

1992-01-01

Discusses the value of journals for understanding a historical period. Suggests that social studies students be encouraged to keep journals to understand better the difference between something written at the time and a later description of the same event. Lists examples of journals from historical periods that may interest students in journal…

Palaeoflood records of the last three centuries from the Pyeongchang and Dong rivers, South Korea

NASA Astrophysics Data System (ADS)

Kim, Song-Hyun; Tanaka, Yukiya

2017-08-01

Slackwater deposits are paleostage indicators in paleoflood hydrology that have commonly been used in numerous studies to estimate the magnitude and frequency of flood events and to reconstruct paleoenvironments and paleohydrology. In this study, individual flood events along the Pyeongchang (PC) and Dong (D) rivers of South Korea were differentiated on the basis of changes in deposit color, grain size, organic content, and the existence of laminations. Based on 137Cs and 14C chronological data, 19 flood events have occurred at site PC since 1720, while 17 flood events have occurred at site D since 1815. At the PC study site, the average time interval between the flood events is 15.4 years and the average sediment accumulation rate is 9.7 mm/y. At study site D, the average time interval is 15 years and the average sediment accumulation rate is 11.6 mm/y. These high sediment accumulation rates are consistent with those in humid areas (e.g., Japan) and explain how slackwater deposits can be preserved despite erosion, bioturbation, and pedogenic processes. Based on the results, the study area was divided into three periods: (1) a relatively wet period (1720-1810 CE), (2) a dry period (1810-1960 CE), and (3) a wet period (1960 CE-present). The flood time intervals and average sediment accumulation rates of the eighteenth century were shorter and higher than those of the nineteenth century. This suggests that on the Korean Peninsula, the paleoclimate of the Little Ice Age (LIA) was wetter than that from the nineteenth century to the early twentieth century.

Impact of a pharmaceutical care program on clinical evolution and antiretroviral treatment adherence: a 5-year study

PubMed Central

Arroyo, María Jesús Hernández; Figueroa, Salvador Enrique Cabrera; Correa, Rosa Sepúlveda; de la Paz Valverde Merino, María; Gómez, Alicia Iglesias; Hurlé, Alfonso Domínguez-Gil

2013-01-01

Background Antiretroviral treatments (ART) form the basis of adequate clinical control in human immunodeficiency virus-infected patients, and adherence plays a primary role in the grade and duration of the antiviral response. The objectives of this study are: (1) to determine the impact of the implementation of a pharmaceutical care program on improvement of ART adherence and on the immunovirological response of the patients; and (2) to detect possible correlations between different adherence evaluation measurements. Methods A 60-month long retrospective study was conducted. Adherence measures used were: therapeutic drug monitoring, a simplified medication adherence questionnaire, and antiretroviral dispensation records (DR). The number of interviews and interventions related to adherence made for each patient in yearly periods was related to the changes in the adherence variable (measured with DR) in these same yearly periods. The dates when the laboratory tests were drawn were grouped according to proximity with the study assessment periods (February–May, 2005–2010). Results A total of 528 patients were included in the study. A significant relationship was observed between the simplified medication adherence questionnaire and DR over the 60-month study period (P < 0.01). Improvement was observed in the mean adherence level (P < 0.001), and there was a considerable decrease in the percentage of patients with CD4+ lymphocytes less than 200 cells/mm3 (P < 0.001). A relationship was found between the number of patients with optimum adherence levels and the time that plasma viral load remained undetected. The number of interviews and interventions performed in each patient in the first 12 months from the onset of the pharmaceutical care program (month 6), was related to a significant increase in adherence during this same time period. Conclusion The results suggest that the establishment and permanence of a pharmaceutical care program may increase ART adherence, increase permanence time of the patient with undetectable plasma viral loads, and improve patients’ lymphocyte count. PMID:23983457

Use of space-time models to investigate the stability of patterns of disease.

PubMed

Abellan, Juan Jose; Richardson, Sylvia; Best, Nicky

2008-08-01

The use of Bayesian hierarchical spatial models has become widespread in disease mapping and ecologic studies of health-environment associations. In this type of study, the data are typically aggregated over an extensive time period, thus neglecting the time dimension. The output of purely spatial disease mapping studies is therefore the average spatial pattern of risk over the period analyzed, but the results do not inform about, for example, whether a high average risk was sustained over time or changed over time. We investigated how including the time dimension in disease-mapping models strengthens the epidemiologic interpretation of the overall pattern of risk. We discuss a class of Bayesian hierarchical models that simultaneously characterize and estimate the stable spatial and temporal patterns as well as departures from these stable components. We show how useful rules for classifying areas as stable can be constructed based on the posterior distribution of the space-time interactions. We carry out a simulation study to investigate the sensitivity and specificity of the decision rules we propose, and we illustrate our approach in a case study of congenital anomalies in England. Our results confirm that extending hierarchical disease-mapping models to models that simultaneously consider space and time leads to a number of benefits in terms of interpretation and potential for detection of localized excesses.

Trajectories of Sleep Quality and Associations with Mood during the Perinatal Period

PubMed Central

Tomfohr, Lianne M.; Buliga, Elena; Letourneau, Nicole L.; Campbell, Tavis S.; Giesbrecht, Gerald F.

2015-01-01

Objective: The aim of this study was to investigate trajectories of sleep quality and associations with mood in the perinatal period. Although it is commonly accepted that subjective sleep quality declines during pregnancy and the transition to parenthood, some women may follow qualitatively distinct trajectories. Design, Setting, and Participants: Sleep quality was assessed by the Pittsburgh Sleep Quality Index (PSQI). Data were collected from 293 women at four time points: during early pregnancy, at Time 1 (T1; < 22 w gestational age [GA]; late pregnancy, at Time 2 (T2; 32 w GA); during the postnatal period at Time 3 (T3; 3 mo postpartum); and Time 4 (T4; 6 mo postpartum). A group-based semiparametric mixture model was used to estimate patterns of sleep quality throughout the perinatal period. Results: Four trajectory groups were identified, including patterns defined by high sleep quality throughout (21.5%), mild decrease in sleep quality (59.5%), significant decrease in sleep quality (12.3%) and a group with poor sleep quality throughout (6.7%). Women who had the worst sleep quality at Time 1 and those who experienced significant increases in sleep problems throughout pregnancy were also the groups who reported the highest levels of anxiety and depressive symptoms in early pregnancy and the lowest levels of social support. After controlling for covariates, the groups with worst subjective sleep quality during pregnancy were also the most likely to experience high symptoms of depression in the postpartum period. Conclusions: Most of the women in our sample reported mild sleep disturbances through the perinatal period. A subgroup of women reported a significant decline in sleep quality from early to late pregnancy and another reported poor subjective sleep quality throughout pregnancy; these groups had the greatest risk of experiencing high symptoms of depression in the postpartum period. Citation: Tomfohr LM, Buliga E, Letourneau NL, Campbell TS, Giesbrecht GF. Trajectories of sleep quality and associations with mood during the perinatal period. SLEEP 2015;38(8):1237–1245. PMID:25845691

A Case Study on Reducing Children's Screen Time: The Project of Screen Free Week

ERIC Educational Resources Information Center

Kara, Hatice Gözde Ertürk

2018-01-01

The current study aims to direct children to alternative activities within a week period by applying the project of screen free week to voluntary families. The ultimate aim of the study is to reduce children's screen time. The instrumental case study method; one of the qualitative research methods, was employed. Five children attending the…

Risk factors for absenteeism due to sick leave in the petroleum industry

PubMed Central

Oenning, Nágila Soares Xavier; Carvalho, Fernando Martins; Lima, Veronica Maria Cadena

2014-01-01

OBJECTIVE To identify risk factors for absenteeism among workers with sick leave in an oil company. METHODS A case-control study (120 cases and 656 controls) nested in a retrospective cohort study following up all employees of an oil company in the North-Northeast of Brazil from 2007 to 2009. The response variable used to represent absenteeism with sick leave was the average incidence of sick leave, defined as the ratio between total sick days and potential working days in the period. Logistic regression techniques were used to investigate the association between average incidence of sick leave > 5.0% over the period and the variables sex, position, age, time at work, shift work, smoking, arterial hypertension, body mass index, physical activity, coronary risk, sleep, glycemia, non-managed diabetes, cardiovascular, digestive, musculoskeletal, neurological and neoplastic diseases, straining body positioning during work, satisfaction at work, relationship with management, and concentrated attention at work. RESULTS Average incidence of sick leave higher than 5.0% in the cohort period was 15.5%. The logistic model revealed that workers with average incidence of sick leave higher than 5.0% were 2.6 times more likely to be female; 2.0 time more likely to be smokers; 1.8 time more likely to be former smokers; 2.2 times more likely to report abnormal sleep and 10.5 times more likely to report dissatisfaction with their than workers with average incidence of sick leave ≤ 5.0% in the period. CONCLUSIONS In this population, female gender, being a smoker or a former smoker, reporting dissatisfaction with the job and reporting abnormal sleep are good predictors of occupational absenteeism with sick leave. PMID:24789643

The use of the local flora in Switzerland: a comparison of past and recent medicinal plant knowledge.

PubMed

Dal Cero, Maja; Saller, Reinhard; Weckerle, Caroline S

2014-01-01

This analysis of documented medicinal plants of the Swiss Flora over the last two millennia provides a rich source of knowledge on earlier uses of plants and use patterns of the local flora. We ask which local plant species were used during different time periods of the last 2000 years and how the numbers of species and the use intensity of specific plant families, growth forms and habitats changed over time. Totally 25 herbals from the antiquity, monastic medicine, Renaissance, early modern era and the contemporary time as well as five recent ethnobotanical studies were considered. Use patterns were analysed with the Bayesian approach. A total of 768 species, i.e. 32% of the vascular plants of the Swiss Flora have been documented as medicinal plants. Numbers increase until the monastic period (366 spp.) and the Renaissance (476) and remain relatively stable since then (modern and contemporary era: 477). But, 465 formerly documented species do not occur in the ethnobotanical studies and thus seem not to be used any more. Overall, 104 species are documented through all time periods. Archeophytes, trees and forest plants are generally overrepresented in herbals from all time periods while plants from above the timberline are generally underrepresented. Most widely used are the Lamiaceae and Apiaceae. A constant body of medicinal plant knowledge in Switzerland exists since ancient time. This knowledge was always influenced by knowledge from neighboring countries and no "typical Swiss specialties" seem to exist. Medicinal plants are not randomly chosen from the available flora. Certain species are deliberately introduced others are neglected. This process, which is still ongoing, can be traced back with the help of herbals to the antiquity. © 2013 Elsevier Ireland Ltd. All rights reserved.

Associations between a history of breast feeding, malocclusion and parafunctional habits in Puerto Rican children.

PubMed

López Del Valle, Lydia M; Singh, G Dave; Feliciano, Nilma; Machuca, María del Carmen

2006-03-01

Studies relating breast-feeding, malocclusion and parafunctional habits in young children are scarce. The purpose of this study is to evaluate the associations of a history of breast-feeding, incidence of malocclusion and parafunctional habits. The dental records of a sample of 540 children aged 6 to 72 months screened for oral conditions and behavioral risk factors were evaluated for variables such as a history of breastfeeding, malocclusion and parafunctional habits. Descriptive statistics using the EPI-INFO Program and Chi-square test at the 0.05 level of probability were performed. The results showed that the mean age of the children was 28 months +/- 14. The mothers' mean age was 26.4 years +/- 6. The prevalence of breast-feeding was 34% with a mean breast-feeding time period of 3 m +/- 3.7. About 95% of the children had a history of bottle-feeding and 90% showed some evidence of malocclusion at the time of dental examination. The main malocclusion problems were space deficiency (closed contacts among incisors) (31%), open bites (6%) and crossbites (5%). A habit of thumb sucking was reported in 32% of the cases and pacifier use in 21%. there were significant differences for the following variables: mother's age and breast-feeding time period; number of children in family and breast-feeding time period; breast-feeding history and breast-feeding time with bottle use, malocclusion and thumb sucking habit; and gender and thumb-sucking habit. It is concluded that breast-feeding practices and time period are behavioral factors that contribute in the prevention of malocclusion in addition to decreasing the practice of parafunctional habits in preschool children.

High-order fuzzy time-series based on multi-period adaptation model for forecasting stock markets

NASA Astrophysics Data System (ADS)

Chen, Tai-Liang; Cheng, Ching-Hsue; Teoh, Hia-Jong

2008-02-01

Stock investors usually make their short-term investment decisions according to recent stock information such as the late market news, technical analysis reports, and price fluctuations. To reflect these short-term factors which impact stock price, this paper proposes a comprehensive fuzzy time-series, which factors linear relationships between recent periods of stock prices and fuzzy logical relationships (nonlinear relationships) mined from time-series into forecasting processes. In empirical analysis, the TAIEX (Taiwan Stock Exchange Capitalization Weighted Stock Index) and HSI (Heng Seng Index) are employed as experimental datasets, and four recent fuzzy time-series models, Chen’s (1996), Yu’s (2005), Cheng’s (2006) and Chen’s (2007), are used as comparison models. Besides, to compare with conventional statistic method, the method of least squares is utilized to estimate the auto-regressive models of the testing periods within the databases. From analysis results, the performance comparisons indicate that the multi-period adaptation model, proposed in this paper, can effectively improve the forecasting performance of conventional fuzzy time-series models which only factor fuzzy logical relationships in forecasting processes. From the empirical study, the traditional statistic method and the proposed model both reveal that stock price patterns in the Taiwan stock and Hong Kong stock markets are short-term.

City-Specific Spatiotemporal Infant and Neonatal Mortality Clusters: Links with Socioeconomic and Air Pollution Spatial Patterns in France.

PubMed

Padilla, Cindy M; Kihal-Talantikit, Wahida; Vieira, Verónica M; Deguen, Séverine

2016-06-22

Infant and neonatal mortality indicators are known to vary geographically, possibly as a result of socioeconomic and environmental inequalities. To better understand how these factors contribute to spatial and temporal patterns, we conducted a French ecological study comparing two time periods between 2002 and 2009 for three (purposefully distinct) Metropolitan Areas (MAs) and the city of Paris, using the French census block of parental residence as the geographic unit of analysis. We identified areas of excess risk and assessed the role of neighborhood deprivation and average nitrogen dioxide concentrations using generalized additive models to generate maps smoothed on longitude and latitude. Comparison of the two time periods indicated that statistically significant areas of elevated infant and neonatal mortality shifted northwards for the city of Paris, are present only in the earlier time period for Lille MA, only in the later time period for Lyon MA, and decrease over time for Marseille MA. These city-specific geographic patterns in neonatal and infant mortality are largely explained by socioeconomic and environmental inequalities. Spatial analysis can be a useful tool for understanding how risk factors contribute to disparities in health outcomes ranging from infant mortality to infectious disease-a leading cause of infant mortality.

City-Specific Spatiotemporal Infant and Neonatal Mortality Clusters: Links with Socioeconomic and Air Pollution Spatial Patterns in France

PubMed Central

Padilla, Cindy M.; Kihal-Talantikit, Wahida; Vieira, Verónica M.; Deguen, Séverine

2016-01-01

Infant and neonatal mortality indicators are known to vary geographically, possibly as a result of socioeconomic and environmental inequalities. To better understand how these factors contribute to spatial and temporal patterns, we conducted a French ecological study comparing two time periods between 2002 and 2009 for three (purposefully distinct) Metropolitan Areas (MAs) and the city of Paris, using the French census block of parental residence as the geographic unit of analysis. We identified areas of excess risk and assessed the role of neighborhood deprivation and average nitrogen dioxide concentrations using generalized additive models to generate maps smoothed on longitude and latitude. Comparison of the two time periods indicated that statistically significant areas of elevated infant and neonatal mortality shifted northwards for the city of Paris, are present only in the earlier time period for Lille MA, only in the later time period for Lyon MA, and decrease over time for Marseille MA. These city-specific geographic patterns in neonatal and infant mortality are largely explained by socioeconomic and environmental inequalities. Spatial analysis can be a useful tool for understanding how risk factors contribute to disparities in health outcomes ranging from infant mortality to infectious disease—a leading cause of infant mortality. PMID:27338439

Floquet-Magnus theory and generic transient dynamics in periodically driven many-body quantum systems

NASA Astrophysics Data System (ADS)

Kuwahara, Tomotaka; Mori, Takashi; Saito, Keiji

2016-04-01

This work explores a fundamental dynamical structure for a wide range of many-body quantum systems under periodic driving. Generically, in the thermodynamic limit, such systems are known to heat up to infinite temperature states in the long-time limit irrespective of dynamical details, which kills all the specific properties of the system. In the present study, instead of considering infinitely long-time scale, we aim to provide a general framework to understand the long but finite time behavior, namely the transient dynamics. In our analysis, we focus on the Floquet-Magnus (FM) expansion that gives a formal expression of the effective Hamiltonian on the system. Although in general the full series expansion is not convergent in the thermodynamics limit, we give a clear relationship between the FM expansion and the transient dynamics. More precisely, we rigorously show that a truncated version of the FM expansion accurately describes the exact dynamics for a certain time-scale. Our theory reveals an experimental time-scale for which non-trivial dynamical phenomena can be reliably observed. We discuss several dynamical phenomena, such as the effect of small integrability breaking, efficient numerical simulation of periodically driven systems, dynamical localization and thermalization. Especially on thermalization, we discuss a generic scenario on the prethermalization phenomenon in periodically driven systems.

Dynamic control of droplets and pockets formation in homogeneous porous media immiscible displacements

NASA Astrophysics Data System (ADS)

Lins, T. F.; Azaiez, J.

2018-03-01

Interfacial instabilities of immiscible two-phase radial flow displacements in homogeneous porous media are analyzed for constant and time-dependent sinusoidal cyclic injection schemes. The analysis is carried out through numerical simulations based on the immersed interface and level set methods. The effects of the fluid properties and the injection flow parameters, namely, the period and the amplitude, on the formation of droplets and pockets are analyzed. It was found that larger capillary numbers or smaller viscosity ratios lead to more droplets/pockets that tend to appear earlier in time. Furthermore, the period and amplitude of the cyclic schemes were found to have a strong effect on droplets/pockets formations, and depending on their values, these can be enhanced or attenuated. In particular, the results revealed that there is a critical amplitude above which droplets and pockets formation is suppressed up to a specified time. This critical amplitude depends on the fluid properties, namely, the viscosity ratio and surface tension as well as on the period of the time-dependent scheme. The results of this study indicate that it is possible to use time-dependent cyclic schemes to control the formation and development of droplets/pockets in the flow and in particular to delay their appearance through an appropriate combination of the displacement scheme's amplitude and period.